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Improving communication barriers for on-site information flow: An exploratory study
Advanced Engineering Informatics 23 (2009) 323–331
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Advanced Engineering Informatics journal homepage: www.elsevier.com/locate/aei
Improving communication barriers for on-site information flow: An exploratory study Ming-Kuan Tsai * Win-Chung Construction Corporation, P.O. Box 946, Taichung 40099, Taiwan
a r t i c l e
i n f o
Article history: Received 9 July 2008 Received in revised form 5 February 2009 Accepted 20 March 2009 Available online 23 April 2009
a b s t r a c t On-site information management is an important issue. Since the lack of on-site information impacts project management, this study focuses on the improvement of on-site information flow. When activity workers report on-site activity information, activity managers can understand the status of on-site activities. This procedure forms the flow of on-site information from the activity workers to the activity managers. By examining a material management case study, this study found that communication barriers affected the on-site information flow, even though several types of information technology were used at the construction site. For improving the communication barriers, this study developed an exploratory system through integrating both wireless and speech technologies. The exploratory system achieved two-way speech communication between the activity workers and operation devices. Information interdependence, human–machine collaboration, and the relationship of project participants were also enhances. In summary, the findings of this study are useful for similar issues in project management. Ó 2009 Elsevier Ltd. All rights reserved.
1. Introduction On-site information management is an important issue, since on-site information is the foundation of successful project management. For example, on-site materials affect activity costs, activity schedules, working labor, site facilities, and material suppliers. If activity managers cannot comprehend on-site material information, activities may fail in the increased activity costs, the delayed activity schedules, the unused working labor, the idle site facilities, and the unreliable material suppliers [1]. Consequently, on-site information management for project management seeks to achieve the following aims (among others): to represent the correct status and the occurring problems of on-site activities; to integrate relevant project information; to satisfy the demand for activity evaluation; and to cooperate with project participants [2,3]. A requirement for all project management systems is obtaining information from activity sites. When activity workers deliver activity reports, activity managers are able to ascertain the status of on-site activities. The above procedure creates the flow of onsite information among activity workers, application systems, operation devices and activity managers. When the on-site information flow is discontinuous, various problems happen to project management. For example, based on the research regarding construction management [4], applying inefficient means for communicating project information is a factor for causing two-thirds of construction problems. The results from the research highlight * Tel.: +886 932637641. E-mail address: [email protected] 1474-0346/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.aei.2009.03.002
the fact that streamlining on-site information flow is both necessary and important. For avoiding that project management is deficient in on-site information, this study focuses on the improvement of on-site information flow. The rest of this paper is organized as follows: section two shows the on-site information flow and communication barriers through a material management case study; section three presents information technology tools and proposes an approach that uses wireless and speech technologies; section four describes the implementation of the approach through the development of an exploratory system; section five illustrates the three system tests; section six shows the test results; section seven presents the discussions regarding the improved efficiency; and section eight draws conclusions. 2. A case study regarding material management 2.1. Case description The examined case study is a 120-day maintenance project for a five-story building. Activities include the floor repair, wall paint, water proofing, and roof drain. The necessary materials include cement, paint, sand, and asphalt. Six material suppliers, located in different cities, offer these materials. For on-site material management, the daily material inspections require three material reports: the inventory report, which records the materials received from suppliers; the use report, which shows the material expenses for the ongoing activities; and the requirement report, which details the materials necessary for the scheduled activities.
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The activity workers had previously recorded material details with a pen and paper; this was a common method for producing material reports. However, handwriting material data is time-consuming [5], since the activity workers need to inspect numerous materials at the construction site. Similarly, the activity managers waste time by waiting for the material reports. To improve management efficiency, the construction company adopts computerbased material reports instead of paper-based material reports. Typical building and civil engineering projects can have dozens (in some cases, hundreds) of activities underway at any one time [6]. The activity workers may not always remain in the site office to complete material reports with computers, since different materials are stored in different working areas. In order to assess the material conditions accurately, the activity workers must check materials within the construction site. The material reports are therefore designed in hypertext and hypermedia representations, since the activity workers enter the on-site material details on their laptops and submit the material reports through the wireless local area networks (WLANs). The activity managers can immediately access these reports. 2.2. Communication barriers Based on the observations of this study, the activity workers unnecessarily type material information at the site office, instead of completing the material reports at the construction site. WLANs not only avoid needless trips between the construction site and the site office, but also increase the speed of information transmissions. When receiving and reading the completed reports, the activity managers can suggest solutions to recurring problems. For the case study, the flow of on-site information from the activity workers to the activity managers seems to be continuous. However, this study recognizes that communication barriers do exist and can affect the production of on-site information. The onsite information flow becomes discontinuous. Fig. 1 depicts the communication barriers. Since the activity workers use their hands to key material details into the laptops, the communication between the activity workers and laptops is manual and passive. For example, while the activity workers are busy with on-site material management, the laptops just wait for data input. As a result, the activity workers spent more time dealing with the collected information. This condition decreases the working productivity, and delays on-site activities. In other words, communication barriers arise because activity workers have no efficient channels to produce immediate data, even though application systems and operation devices are in good working order. For example, the activity workers have difficulties transferring material reports through the laptops and WLANs when performing material inspections by hand. Besides, communication barriers may cause information overload for activity workers. As Fig. 1 shown, although the activity workers have a large amount of on-site information, they cannot transfer information to the application systems, operation devices, and activity manag-
WLAN environments
recording material details by hand On-site
Activity
materials
worker Information overload
System Device
Activity manager
ers. For the case study, the main cause of the communication barriers is the distance between the activity workers and application systems, since the activity workers are busy with material inspections and move away from the operation devices. 3. Information technologies for on-site information flow 3.1. Literature review In order to remove these barriers, applying information technologies (IT) to the examined on-site information flow may be useful. The key advantage of IT-based solutions is that the activity workers can avoid depending on memory while completing material reports [7]. The common IT applications include: Mobile computing: Mobile computing enhances project management by providing activity workers with different kinds of information relating to building standards, materials, activities, and reprocesses in working periods [8]. When staying at construction sites, activity workers and managers have the ability to complete many administrative jobs by using mobile devices. For example, Kuladinithi et al. [9] thought that wearable computing, along with advanced mobile communication, had the potential to revolutionize the working environment and processes of the mobile worker in the AEC industry. Kimoto et al. [10] integrated PDAs with construction management so that activity workers could flexibly process data at construction sites. Wang et al. [11] proposed a PDA- and RFID-based dynamic supply chain management system in construction projects. Bar-code system: This system uses optical scanners to capture the information stored in bar-code labels. The mapping between the captured information and the scanned bar-codes is called ‘‘symbology,” which is necessary to encode digits and characters [12]. For example, while scanning bar-code labels, activity workers can understand both the material name and the quantity. These will automatically be recorded into reports. Since activity workers simultaneously check materials and complete material records at construction sites, activity managers are able to obtain material reports quickly. A bar-code system can also be useful in reducing construction wastes [13]. Global positioning system (GPS): GPS is a satellite-based radionavigation system. There are 24 GPS satellites orbiting the earth and transmitting radio signals. When a radio signal travels from a satellite to a receiver, GPS measures the amount of time and calculates the distance to determine the location in terms of longitude, latitude, and altitude. GPS applications are commonly used at construction sites to keep track of vehicle locations and material transmission [14]. Radio frequency identification (RFID): RFID is an automatic identification solution that streamlines data recognition and information acquisition, operating in a manner similar to bar-codes. An RFID system is composed of an RFID tag and an RFID reader. An RFID tag comprises a small microchip and an antenna. Data are normalized as a unique serial number and stored in RFID tags. RFID tags can be read within the radio range of RFID readers. When a PDA connects with an RFID scanner, the RFID-enabled PDA becomes a powerful portable data collection tool [15,16]. Future material-tracking management systems may be able to provide site owners with the ability to determine activity progress and materials delivered, simply by walking around a site where all materials are identified and tagged using an RFID system [17].
Communication barriers
Fig. 1. The communication barriers for the examined on-site information flow.
Based on the above descriptions, various information technologies are unique and useful tools. However, the GPS technique is not suitable for the case study because this study does not track the
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location of material transport. For example, activity workers cannot use GPS applications to determine whether or not ongoing activities require materials. The other information technologies mentioned above do not remove the communication barriers described in this study either, because the activity workers still need to apply operation devices to acquire material details by hand. According to the research on document management systems, Zantout and Marir [18] suggested that an embedded intelligent agent could enhance information transmission and avoid future delay. When an information system supports direct two-way communication, the coordinated cooperation among the activity workers, application systems, and operation devices will be carried out [8]. Consequently, this study proposes an approach that will enable activity workers to exchange information with operation devices when they do not have the use of their hands. 3.2. Approach for improvement According to research [19], human beings can speak 280 words per minute; however, they can only key in 15 words per minute via PDAs and 50 words per minute through keyboards. Besides, activity workers can produce information via speech when busy with on-site activities. Since speech technology can provide flexible interactions, many researchers have used speech-enabled applications in several fields. For example, Reddy et al. [20] created a voice-operated information system for drivers; Goose et al. [21] proposed the voice portal and a web-hosted converter in order to enhance web accessibility; and Chen and Tsai [22] developed a speech-enabled system for electronic commerce network environments. Integrating a speech system with the examined on-site information flow seems to be possible. This study compares a speech system with bar-code and RFID systems (Table 1). The three information technologies all require different operation devices to recognize information. These operation devices can transfer information from construction sites to site offices via WLANs. However, two-way communication is difficult for bar-code and RFID systems. For example, activity workers can receive information from bar-code labels and RFID tags, but the labels and tags cannot receive information from activity workers. Since a speech system can actively confirm information with activity workers, these workers may receive information when they move away from operation devices. If the activity workers find erroneous data in the received responses, the system can automatically modify the data when the activity workers prompt the said system. Excluding necessary communication facilities (e.g., a headset), the system does not require any additional costs. Based on this comparison, for the case study, a speech system not only removes the communication barriers, but also satisfies the project cost requirements.
Table 1 The comparison among bar-code, RFID, and speech systems. Evaluation
Bar-code
RFID
Speech
How is information stored?
Bar-code labels Bar-code readers One-way
RFID tags
Voice
How is the stored information received? What is the communication relationship between activity workers and operation devices? How are errors modified? Can the solution transfer information within WLANs? Does the solution require additional costs?
RFID readers One-way
Electronic devices Two-way
Manual Yes
Manual Yes
Automatic Yes
Yes
Yes
No
To achieve speech communication between an activity worker and a speech system, three processes (‘‘automatic speech recognition,” ‘‘text to speech,” and ‘‘auditory recognition”) are necessary. Fig. 2 shows that a speech system will use speech recognition to analyze the received details when an activity worker gives oral commands; this process is called automatic speech recognition (ASR). The speech system will then provide the results to the activity worker through speech synthesis; this process is known as text to speech (TTS). After hearing the speech-format responses, the activity worker will know whether the commands have been executed correctly; this process is auditory recognition (AR) [23,24]. This communication procedure is similar to human conversations. Likewise, if an operation device clearly receives speech and a speech system correctly recognizes the speech, the activity workers will obtain greater working efficiency within the on-site information flow. Moreover, wireless technologies will be helpful for data transmission when there is the distance between activity workers and operation devices. Besides WLANs, the Bluetooth technique can assist activity workers in synchronous data exchange among different devices (e.g., mobile phones and hand-held computers). The short-range speech connections of walkie-talkie communication are the common Bluetooth applications, because the wireless link between different devices can reach 30 feet [25]. Consequently, the approach for improving the examined on-site information flow is to integrate wireless and speech technologies. 4. Approach implementation This study develops an exploratory system to implement the approach. A successful application system must integrate present requirements in a way that reduces the current burden while activity workers use the system for their normal tasks [7]. According to the actual working processes, this study completed the system development through three steps: ‘‘producing on-site information,” ‘‘confirming on-site information,” and ‘‘submitting on-site information.” 4.1. Producing on-site information For the case study, Fig. 3 shows the information transmission procedure between the activity workers and the exploratory system. In Step 1A, the activity workers described material details according to the classification of material records (such as an inventory record, a use record, and a requirement record). Table 2 shows material records, comprising the necessary data fields. The material inventory, use, and requirement records were composed of 7, 6, and 7 data fields, respectively. Previously, while receiving the sentence-format material details, the application system could not recognize this information. Therefore, the activity workers had to complete each required data field separately. The
Human
Machine
Speech
Automatic
commands
Speech Recognition (ASR)
Auditory
Text
Recognition
To
(AR)
Speech (TTS)
Fig. 2. The procedure for human–machine communication.
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Start
The activity workers
Step 1A:
The exploratory system
Step 1B:
material
Checking materials
Analyzing details
details analyzed results
Step 2B:
Step 2A: Confirming results
Modifying data
incorrect data
Database Step 3A: correct
WLANs
Submitting data
Step 3B: Saving
data
data
Recording
Completing
Next cycle
End
reports
another record
Switching to another report Fig. 3. The flowchart for the examined on-site information flow.
Table 2 The requiring data fields and sentence models for various material records. Record types
Data fields
Conjunctive words
Sentence models
Examples
Material inventory record
The seven data fields are: (1) defined material number; (2) material name; (3) material quantity; (4) storing location; (5) supplier name; (6) material test and (7) testing report number The six data fields are: (1) defined material number; (2) material name; (3) material quantity; (4) activity name; (5) activity location and (6) worker name The seven data fields are: (1 and 2) requirement date (month and day); (3) defined material number; (4) material name; (5) material quantity; (6) activity name and (7) activity location
‘‘delivers,” ‘‘of,” ‘‘to,” and ‘‘with”
Supplier name delivers material quantity of material name to storing location with material test testing report number
Jet company delivers six tons of steel to the first floor with no testing.
‘‘does,” ‘‘in,” ‘‘and,” ‘‘uses,” and ‘‘of”
Worker name does activity name in activity location and uses material quantity of material name
Tsai does wall repair in the third floor and uses two bags of cement
‘‘needs,” ‘‘of,” and ‘‘on”
Activity location activity name needs material quantity of material name on month day
The third floor wall repair needs ten bags of cement on September 5
Material use record
Material requirement record
inconvenient data input delayed the production of on-site information. However, these data fields can combine to form speech structures. For example, the activity workers fill the material name (steel) and quantity (ten tons) in the material reports, or, similarly, the activity workers can say ‘‘ten tons of steel”. Table 2 shows that this study constructed three sentence models (consisting of the data fields and conjunctive words). For completing various material records, the exploratory system stored the data fields and deleted the conjunctive words. For example, when creating a material inventory record, the activity workers could speak ‘‘jet company delivers 6 tons of steel to the first floor with no testing (sup-
plier name delivers material quantity of material name to storing location with material test testing report number)”. The data fields were ‘‘jet company (supplier name)”, ‘‘6 tons (material quantity)”, ‘‘steel (material name)”. ‘‘the first floor (storing location)”, and ‘‘no testing (material test)”, and the conjunctive words were ‘‘delivers”, ‘‘of”, ‘‘to”. and ‘‘with”. To ensure that the activity workers could smoothly describe material conditions via speech and the speech-format sentences could be recognized, this study integrated ‘‘grammar rules” and speech tags with the exploratory system. Grammar consists of sets of utterances (such as words and phrases) that are helpful for increasing the accuracy of speech recognition [26]. When the activ-
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ity workers accessed the material reports, the grammar rules and the defined vocabulary (such as the date, names, location, and workers required for the activity, the necessary materials, material suppliers, and the conjunctive words) were loaded onto the exploratory system. Fig. 4 shows the architecture of the exploratory system. In order to represent the Internet-based and speech-enabled material reports, this study used XHTML + Voice standard [26] and programming languages (e.g., ASP.Net [27] and JSP [28]) to build all system components. The Web server, which consisted of Microsoft Windows Server 2003 [29] and Microsoft IIS 6 [30], offered information exchange between the construction site and the site office. The database server (Microsoft SQL Server 2005 [31]) was another important component for storing all of the material data (including the vocabulary and records). Since the exploratory system combined speech functions and the existing Internet-based material reports, this study did not alter database frameworks and tables. When on-site information transferred from Step 1A to Step 1B (Fig. 3), the exploratory system automatically analyzed the received speech-format material details through ASR and TTS. The pronunciation and speaking behaviors of activity workers varied, and therefore influenced the accuracy of speech recognition. For example, in the case study all Taiwanese activity workers pronounced ‘‘sand” as ‘‘sa” or ‘‘sa-gi” in Chinese. The activity workers also had difficulty in remembering all defined material numbers. For better speech recognition, editing the relational calling names and corresponding numbers of same materials was a necessary process. While receiving the speech-format sentences from the activity workers, the exploratory system simultaneously identified the matching data and filled in the material reports. 4.2. Confirming on-site information After Steps 1A and 1B (Fig. 3), Step 2A shows that the exploratory system communicated the analyzed results to the activity workers through TTS. When hearing the speech responses, the activity workers could confirm whether the recognized and recorded data were correct. However, there is the possibility of unforeseen situations. For example, a spoken sentence did not contain all material details; the exploratory system did not completely recognize the speech entry; and the exploratory system produced erroneous data. In Step 2B, the activity workers modified the incorrect record with the exploratory system by using speech commands. For example, if the material quantity was incorrect, the activity worker could speak ‘‘quantity” to prompt the exploratory system. The system then asked the activity worker to repeat the material quantity.
XHTML+Voice documents
4.3. Submitting on-site information If the record was initially correct, or was corrected by the activity worker, Fig. 3 shows that the exploratory system submitted the material record through WLANs (Step 3A). When receiving the submitted record, the Web server saved the material data into the database (Step 3B). Finally, the activity workers could process other material records, switch to another material report, or exit the system to complete material reports. Clearly, the above on-site information flow was continuous even though there was the distance between the activity workers and the exploratory system throughout the working periods. In summary, Fig. 5 displays the improved on-site information flow when this study implemented the approach. WLAN environments offered the convenient platform for the information exchange and Bluetooth connections enabled the activity workers to communicate directly with the exploratory system and the operation device via speech. The exploratory system could intelligently recognize the inputted information, actively process the recorded results, and immediately submit the confirmed reports. The communication barriers identified in Fig. 1 were eliminated. The activity managers were able to understand the on-site material status even though the activity workers were not at the site office. 5. System tests After completing the system development, this study performed various system tests to determine whether the exploratory system could work in the case study. Five male activity workers (testers) participated in the tests and their age ranged from 27 to 32 years old. All testers had two to four years of experience in on-site material management, and one of the testers even participated in designing material reports. None of the testers had previous experience with speech-enabled applications, so they were trained to understand these communication methods. The three system tests were: Initial system tests: This study confirmed whether the testers performed speech communication successfully. When inspecting material status, each tester worked with 15 different material records (obtaining five inventory records, five use records and five requirement records) with the previous system (the activity workers completing material reports by hand) and the exploratory system (the activity workers completing material reports via speech) at the construction site. For example, the testers manually entered the data fields to complete a material use record in the previous system. For the exploratory system, they could finish the similar record via speech. Table 2 shows that the testers spoke ‘‘Tsai does wall repair in the third floor and uses two bags of cement (worker name does activity name in activity location and uses material quantity of material name)”. After automatically deleting the conjunctive words
(representing material records)
WLAN environments Activity worker
Microsoft SQL Server 2005
recording material details via speech
(storing material data) Web server: Microsoft Windows Server 2003 and IIS 6 (offering information exchange) construction site
On-site
Activity
System
materia
worker
Device
Bluetooth connections
site office
Fig. 4. The architecture of the exploratory system.
Fig. 5. The improved on-site information flow.
Activity manager
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(including ‘‘does”, ‘‘in”, ‘‘and”, ‘‘uses”, and ‘‘of”), the exploratory system stored the data fields (including ‘‘Tsai (worker name)”, ‘‘wall repair (activity name)”, ‘‘the third floor (activity location)”, ‘‘two bags (material quantity)”, and ‘‘cement (material name)”). System tests for communication barriers: The testers performed the system tests without carrying the laptops, because Bluetooth technology enabled information transmission within different distance environments. According to the test results, this study could confirm whether the communication barriers were removed when the activity workers moved away from the laptops. For example, although the testers did not touch the laptops, Table 2 shows that they completed a material requirement record by speaking ‘‘the third floor wall repair needs ten bags of cement on September 5 (activity location activity name needs material quantity of material name on month day)”. If the exploratory system successfully classified the data fields (including ‘‘the third floor (activity location)”, ‘‘wall repair (activity name)”, ‘‘ten bags (material quantity)”, ‘‘cement (material name)”, and ‘‘September 5 (month day)”) and the conjunctive words (including ‘‘needs”, ‘‘of”, and ‘‘on”), the communication barriers were overcame. Long-period system performance: This study chose one tester, having the best performance in the initial system tests, to apply the exploratory system in order to complete material reports for 14 working days. Based on the test results, this study could understand the differences between the previous and exploratory systems. During the period of system tests, the measuring items were: data fields, erroneous data, accuracy rate, operation time, and time efficiency. The long-term reliability of inputting data via keyboards was prone to human errors. Moreover, background noise remains a significant variable for the performance of a speech-enabled system. When the noise level exceeds 90 dB, humans are uncomfortable and have difficulty with auditory recognition [24,32]. To process speech and auditory recognition, the noise level of system tests was less than 80 dB. As incorrect material records were not useful for material management, the testers modified erroneous data, the process defined as the data modification and included the operation time. This study used Eq. (1) to determine the accuracy of information production:
fields errs 100% accuracy rate ¼ fields
ð1Þ
where the fields are data fields and the errs are erroneous data. In addition, a computerized approach for collecting site information could be recorded and processed to produce immediate feedback on the project status and problems [7]. The improved operation time certainly influenced the decision of the activity workers to apply a new computerized system. Eq. (2) was applied to identify the time efficiency:
time efficiency ¼
pre OT OTexp 100% OTpre
ð2Þ
where the OTpre is total operation time for the previous system and the OTexp is total operation time for the exploratory system. 6. Test results This study details the results of initial system tests (Table 3), system tests for communication barriers (Table 4) and long-period system performance (Table 5) in the following sections. 6.1. Initial system tests For the system tests in the previous system, Table 3 shows that testers 1, 2, and 4 spent 300, 295, and 303 s, respectively, correctly completing 15 material records (100 data fields). Although having incorrect inputs, testers 3 and 5 spent 300 and 304 s completing all records (including the data modification), respectively. Compared to key-in speed, the accuracy rate was not an absolute factor in the test results, since the testers did not spend much time modifying errors. For example, the operation time of tester 3 was similar to that of tester 1. When performing the same tests in the exploratory system, testers 2 and 3 spent 245 and 255 s on correctly completing the material reports, respectively. To modify the incorrect data, testers 1, 4 and 5 spent 273, 281 and 277 s on finishing all material records, respectively. For the exploratory system, the procedure of data confirmation was different from the previous system. The testers identified errors and used the exploratory system to reprocess speech recognition. The system responded by asking for the incorrect material record. Because the operation time accounted for the conversion time between the activity workers and the exploratory system, the operation time of testers 1, 4 and 5 was longer than that of testers 2 and 3. The average accuracy rates of previous and exploratory systems were 99.4% and 99%, respectively. When the average operation time of the previous system was 300 s and that of the exploratory system was 266 s, the average time efficiency reached 11.33% (Eq. (2)). Based on the average performance of system tests, the testers
Table 4 The system tests for communication barriers. Tester
Data fields
The exploratory system Errors
Accuracy rate (%)
Operation time (s)
98 100 97 99 100
288 265 303 279 271
1 2 3 4 5
100 100 100 100 100
2 0 3 1 0
Average
100
1.2
98.8
281
Table 3 The test results for initial system tests. Tester
Data fields
The previous system Operation time (s)
Errors
Accuracy rate (%)
Operation time(s)
100 100 99 100 98
300 295 300 303 304
2 0 0 2 1
98 100 100 98 99
273 245 255 281 277
9.00 16.95 15.00 7.26 8.88
300
1
99
266
11.33a
100 100 100 100 100
0 0 1 0 2
Average
100
0.6
300
100%.
Time efficiency (%)
Accuracy rate (%)
1 2 3 4 5
a ð300266Þ
The exploratory system
Errors
99.4
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M.-K. Tsai / Advanced Engineering Informatics 23 (2009) 323–331 Table 5 The test results for long-period system performance. Material records
The previous system
Day
Inventory
Use
Requirement
1 2 3 4 5 6 7 8 9 10 11 12 13 14
10 5 7 5 5 8 4 5 7 4 5 6 6 8
12 9 11 14 14 10 8 13 10 10 6 8 10 7
6 2 7 5 3 5 2 3 0 3 2 0 1 3
Total a ð173411Þ
1734 b ð173413Þ
1734
Errors
184 103 164 154 140 151 90 134 109 109 85 90 109 119
2 0 1 1 0 1 0 2 1 0 0 0 2 1
1734
11
Accuracy rate (%) 98.87 100.00 99.39 99.35 100.00 99.34 100.00 98.51 99.08 100.00 100.00 100.00 98.17 99.16 99.37a
The exploratory system Operation time (s)
Errors
523 306 480 452 410 450 267 397 319 323 252 263 323 353
2 1 0 2 3 0 0 1 0 2 1 0 1 0
5118
13
Accuracy rate (%) 98.87 99.03 100.00 98.70 97.86 100.00 100.00 99.25 100.00 98.17 98.82 100.00 99.08 100.00 99.25b
Operation time (s) 462 278 405 419 398 376 229 353 280 298 221 230 290 298 4537
Time efficiency (%)
11.66 9.15 15.63 7.30 2.93 16.44 14.23 11.08 12.23 7.74 12.30 12.55 10.22 15.58 11.35c
100%. 100%.
c ð51184537Þ
5118
Data fields
100%.
produced and delivered the on-site material information efficiently when performing the speech communication with the exploratory system. Overall, the testers were able to use speech to complete material reports with the exploratory system, integrating both Bluetooth and WLAN environments. 6.2. System tests for communication barriers This study had no test results when there were communication barriers in the previous system. The testers could not complete material reports when they were away from their laptops. For the exploratory system, auditory recognition and speech communication, rather than visual displays, were the main methods of two-way information exchange. When the laptops were placed on the floor, the testers could describe the material details via speech and complete material records at a distance up to 30 ft. Table 4 illustrates that testers 2 and 5 spent 265 and 271 s, respectively, completing material reports with the exploratory system. To modify the erroneous data, testers 1, 3 and 4 spent 288, 303 and 279 s finishing the system tests, respectively. The average operation time and accuracy rate were 281 s and 98.8%. Obviously, the testers successfully communicated with the exploratory system to complete the on-site material reports without having to carry the laptop. This study improved the communication barriers for the case study.
The initial test results in Table 3 show that the best operation time of tester 2 was 245 s for 100 data fields, using the exploratory system. Under this system, the ideal operation time for tester 2 would be 4248 s for 1734 data fields. As a result of 13 errors caused by speech recognition (Table 5), the actual executed data fields totaled 1747. Therefore, tester 2 spent 4537 s completing all material records. For modifying errors, the time difference (289 s) of the both actual and ideal operation time was understandable and reasonable. When the total accuracy rates of previous and exploratory systems were 99.37% and 99.25%, the time efficiency was 11.35% (Table 5). Fig. 6 shows that the cumulative time difference increased with the number of working days. For the long-period system tests, tester 2 produced speech-format material information conveniently and quickly. The confirmed material records were delivered into material reports automatically. To summarize, the exploratory system offered a better environment for the on-site information flow. 7. Discussions Based on the above descriptions, this study improved the examined on-site information flow. This study then compared the previous and exploratory systems, and classified their main differences. For project management, the advantages of the exploratory system are:
6.3. Long-period system performance This section of the study focused on long-period system performance. Tester 2, having the best test result in the initial system tests, applied the exploratory system in the on-site material management for 14 working days. According to the test results of the initial system tests for the previous system, Table 3 shows that the best operation time of tester 2 was 295 s for 100 data fields. In the 14 working days, the total requiring data fields of the previous system (Table 5) were 1734. The ideal operation time (defined as the assumed best operation time) would be 5115 seconds for completing all data fields. However, the total number of erroneous data items was 11, which increased the actual number of executed data fields to 1745. Since errors did not seriously influence the data modification, the actual operation time (5118 s) was close to the ideal operation time.
Information interdependence: On-site information immediately transferred from activity workers to operation devices and activity managers. This condition lessened information overload for the activity workers. The lack of real-time information for offsite data analysis was also improved. Since project participants obtained time and space to resolve any unexpected problems, they benefited from the interdependence of compact information. For example, the construction company had several ongoing projects in the case study. To save on material costs, the construction company ordered quantities of similar material from a supplier, based on the requirements. According to the details of the order, the supplier transported the material to the different construction sites. If the activity workers received an incorrect
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The previous system
The exploratory system
6000
atory system did not have an impact on the project cost and the database files. When activity workers applied the exploratory system at activity sites, this system required no additional costs.
Operation time (sec)
5000
When activity workers and managers applied other small-size devices (e.g., PDAs and smart-phones) for project management, the activity workers were able to access the exploratory system. The system also had the potential to be combined with other similar project reports and information flows. Considering the project losses caused by the lack of on-site information, the exploratory system was an efficient application. For example, if the cost of an activity laborer was USD 70 per day, the construction company lost USD 350 per day when a five-person activity was delayed by material shortages.
4000
3000
2000
1000
8. Conclusions 0 1
2 3
4
5 6
7
8
9 10 11 12 13 14
Day Fig. 6. The cumulative operation time for 14 working days.
quantity of the material, the activity managers and the construction company required real-time information (including material name, quantity, and supplier name) to contact the supplier. Enhancing relative project management: Activity workers and managers cooperated with various project participants for on-site activities. Immediate on-site information compactly connected the cooperation relationship, and ensured that the activity managers effectively allocated on-site resources. For example, although activity managers ordered five tons of steel some days ago, activity workers could not receive the steel on the required day, since material suppliers required time to prepare and transport the steel. If the activity managers discussed the delivery period with the material suppliers, the lack of steel could be resolved. The activity managers could also transfer the required steel from other construction projects, or revise the activity schedules. Proper human–machine collaboration: For most IT-based solutions, the human–machine collaboration required activity workers to face the application systems and operation devices. Comparatively, the exploratory system actively interacted with activity workers, even though the activity workers did not touch the operation devices. By reducing unnecessary movement between the activities and operation devices, the activity workers were able to focus on the ongoing processes. For example, in the case study, the activity workers inspected an activity and counted the remnant quantity of activity materials. When the activity workers reported the details, via speech, through Bluetooth headsets, the laptops recognized and transferred the receiving information even though the activity workers were not near the laptops. If the activity managers understood that the remaining quantity of activity materials was low, they could immediately discover the causes of the shortage, which might include incorrect activity processes, resource waste, or an erroneous order. The satisfying development and application cost: This study developed the exploratory system based on the reports in use and the existing information equipments. In other words, the explor-
For project management, activity managers require much information from numerous on-site information flows. Efficient information production and transmission between activity workers and application systems smooth the flow of on-site information. Although various IT-based solutions can assist activity workers in transmitting information, this study recognizes that communication barriers affect information production. The onsite information flow from activity workers to the activity managers was then interrupted. For example, this study examined a number of activities at construction sites. Since the activity workers were busy with activity processes and away from the operation devices, the activity managers could not obtain activity information. The construction company wasted resources on the activities. Consequently, this study applied an approach for the communication barriers and on-site information flow. In a material management case study, this study developed an exploratory system by integrating both wireless and speech technologies. During the period of system tests, the testers successfully used the exploratory system for completing material reports. The cost requirements for the system development and applications were satisfactory. Two-way communication between the testers and the exploratory system achieved the proper human–machine collaboration. The construction company and project participants benefited from information interdependence. For future research, this study will apply the exploratory system to similar issues in project management. Acknowledgements The author thanks Win-Chung Construction Corporation and all participants for this study. References [1] L.C. Bell, G. Stukhart, Attributes of materials management systems, Journal of Construction Engineering and Management 112 (1) (1986) 14–21. [2] D.U. Kini, Materials management: the key to successful project management, Journal of Management in Engineering 11 (1) (1999) 30–34. [3] R.M. William, J. Hal, Construction Jobsite Management, Delmar Publishers, New York, 1998. [4] N. Dawood, A. Akinsola, B. Hobbs, Development of automated communication of system for managing site information using internet technology, Automation in Construction 11 (2002) 557–572. [5] D.A. Pogorilich, The daily report as a job management tool, Cost Engineering 34 (2) (1992) 23–25. [6] A.D. Russell, Automated interpretation of job site records, in: Proceedings Second Congress of Computing in Civil Engineering, ASCE, Atlanta, 1995, pp. 989–996. [7] A.D. Russell, Computerized daily site reporting, Journal of Construction Engineering and Management 119 (2) (1993) 385–402.
M.-K. Tsai / Advanced Engineering Informatics 23 (2009) 323–331 [8] G.B. Coker, Information system for building products, Journal of Construction Engineering and Management 111 (4) (1985) 411–424. [9] K. Kuladinithi, A. Timm-Giel, C. Gorg, Mobile AD-HOC communications in AEC industry, ITcon 9 (2004) 313–323. [10] K. Kimoto, K. Endo, S. Iwashita, M. Fujiwara, The application of PDA as mobile computing system on construction management, Automation in Construction 14 (2005) 500–511. [11] L.C. Wang, Y.C. Lin, P.H. Lin, Dynamic mobile RFID-based supply chain control and management system in construction, Advanced Engineering Informatics 21 (2007) 377–390. [12] W.J. Rasdorf, M.J. Herbert, Automated identification system – focus on bar coding, Journal of Computing in Civil Engineering 4 (3) (1990) 279–296. [13] Z. Chen, H. Li, T.C. Wong, An application of bar-code system for reducing construction wastes, Automation in Construction 11 (2002) 521–533. [14] A.A. Oloufaa, M. Ikedab, H. Odab, Situational awareness of construction equipment using GPS, wireless and web technologies, Automation in Construction 12 (2003) 737–748. [15] E. Ergen, B. Akinci, R. Sacks, Life-cycle data management of engineered-toorder components using radio frequency identification, Advanced Engineering Informatics 21 (2007) 356–366. [16] L.C. Wang, Enhancing construction quality inspection and management using RFID technology, Automation in Construction 17 (2008) 467–479. [17] B. Atkin, R. Leiringer, Mapping IT innovation in facilities management, ITcon 11 (2006) 673–684. [18] H. Zantout, F. Marir, Document management systems from current capabilities towards intelligent information retrieval: an overview, International Journal of Information Management 19 (1999) 471–484. [19] Multitel Corp, Multimedia Telecommunication, IFAWC, 2004.
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[20] P.D.V.G. Reddy, R. Kitamura, P.P. Jovanis, Voice operated information system (VOIS) for driver’s route guidance, Mathematical and Computer Modelling 22 (4) (1995) 269–278. [21] S. Goose, M. Newman, C. Schmidt, L. Hue, Enhancing web accessibility via the vox portal and a web-hosted dynamic HTML<->VoxML converter, Computer Networks 33 (2000) 583–592. [22] M.Y. Chen, M.J. Tsai, The Study of the VoiceXML Mandarin Dialog System in the E-Commerce Networking Environment, Institute of Information Management, Nation Chiao-Tung University, Taiwan, 2002. [23] K.R. Abbott, Voice Enabling Web Applications: VoiceXML and Beyond, Apress, California, 2001. [24] S.C. Wang, Digital Processing of Speech Signals, ChWa Company, Taiwan, 2004. [25] N.J. Muller, Bluetooth Demystified, McGraw-Hill Company, New York, 2000. [26] W3C Working Draft. Available from:. [31] Microsoft SQL server 2005. Available from:
Contents lists available at ScienceDirect
Advanced Engineering Informatics journal homepage: www.elsevier.com/locate/aei
Improving communication barriers for on-site information flow: An exploratory study Ming-Kuan Tsai * Win-Chung Construction Corporation, P.O. Box 946, Taichung 40099, Taiwan
a r t i c l e
i n f o
Article history: Received 9 July 2008 Received in revised form 5 February 2009 Accepted 20 March 2009 Available online 23 April 2009
a b s t r a c t On-site information management is an important issue. Since the lack of on-site information impacts project management, this study focuses on the improvement of on-site information flow. When activity workers report on-site activity information, activity managers can understand the status of on-site activities. This procedure forms the flow of on-site information from the activity workers to the activity managers. By examining a material management case study, this study found that communication barriers affected the on-site information flow, even though several types of information technology were used at the construction site. For improving the communication barriers, this study developed an exploratory system through integrating both wireless and speech technologies. The exploratory system achieved two-way speech communication between the activity workers and operation devices. Information interdependence, human–machine collaboration, and the relationship of project participants were also enhances. In summary, the findings of this study are useful for similar issues in project management. Ó 2009 Elsevier Ltd. All rights reserved.
1. Introduction On-site information management is an important issue, since on-site information is the foundation of successful project management. For example, on-site materials affect activity costs, activity schedules, working labor, site facilities, and material suppliers. If activity managers cannot comprehend on-site material information, activities may fail in the increased activity costs, the delayed activity schedules, the unused working labor, the idle site facilities, and the unreliable material suppliers [1]. Consequently, on-site information management for project management seeks to achieve the following aims (among others): to represent the correct status and the occurring problems of on-site activities; to integrate relevant project information; to satisfy the demand for activity evaluation; and to cooperate with project participants [2,3]. A requirement for all project management systems is obtaining information from activity sites. When activity workers deliver activity reports, activity managers are able to ascertain the status of on-site activities. The above procedure creates the flow of onsite information among activity workers, application systems, operation devices and activity managers. When the on-site information flow is discontinuous, various problems happen to project management. For example, based on the research regarding construction management [4], applying inefficient means for communicating project information is a factor for causing two-thirds of construction problems. The results from the research highlight * Tel.: +886 932637641. E-mail address: [email protected] 1474-0346/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.aei.2009.03.002
the fact that streamlining on-site information flow is both necessary and important. For avoiding that project management is deficient in on-site information, this study focuses on the improvement of on-site information flow. The rest of this paper is organized as follows: section two shows the on-site information flow and communication barriers through a material management case study; section three presents information technology tools and proposes an approach that uses wireless and speech technologies; section four describes the implementation of the approach through the development of an exploratory system; section five illustrates the three system tests; section six shows the test results; section seven presents the discussions regarding the improved efficiency; and section eight draws conclusions. 2. A case study regarding material management 2.1. Case description The examined case study is a 120-day maintenance project for a five-story building. Activities include the floor repair, wall paint, water proofing, and roof drain. The necessary materials include cement, paint, sand, and asphalt. Six material suppliers, located in different cities, offer these materials. For on-site material management, the daily material inspections require three material reports: the inventory report, which records the materials received from suppliers; the use report, which shows the material expenses for the ongoing activities; and the requirement report, which details the materials necessary for the scheduled activities.
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The activity workers had previously recorded material details with a pen and paper; this was a common method for producing material reports. However, handwriting material data is time-consuming [5], since the activity workers need to inspect numerous materials at the construction site. Similarly, the activity managers waste time by waiting for the material reports. To improve management efficiency, the construction company adopts computerbased material reports instead of paper-based material reports. Typical building and civil engineering projects can have dozens (in some cases, hundreds) of activities underway at any one time [6]. The activity workers may not always remain in the site office to complete material reports with computers, since different materials are stored in different working areas. In order to assess the material conditions accurately, the activity workers must check materials within the construction site. The material reports are therefore designed in hypertext and hypermedia representations, since the activity workers enter the on-site material details on their laptops and submit the material reports through the wireless local area networks (WLANs). The activity managers can immediately access these reports. 2.2. Communication barriers Based on the observations of this study, the activity workers unnecessarily type material information at the site office, instead of completing the material reports at the construction site. WLANs not only avoid needless trips between the construction site and the site office, but also increase the speed of information transmissions. When receiving and reading the completed reports, the activity managers can suggest solutions to recurring problems. For the case study, the flow of on-site information from the activity workers to the activity managers seems to be continuous. However, this study recognizes that communication barriers do exist and can affect the production of on-site information. The onsite information flow becomes discontinuous. Fig. 1 depicts the communication barriers. Since the activity workers use their hands to key material details into the laptops, the communication between the activity workers and laptops is manual and passive. For example, while the activity workers are busy with on-site material management, the laptops just wait for data input. As a result, the activity workers spent more time dealing with the collected information. This condition decreases the working productivity, and delays on-site activities. In other words, communication barriers arise because activity workers have no efficient channels to produce immediate data, even though application systems and operation devices are in good working order. For example, the activity workers have difficulties transferring material reports through the laptops and WLANs when performing material inspections by hand. Besides, communication barriers may cause information overload for activity workers. As Fig. 1 shown, although the activity workers have a large amount of on-site information, they cannot transfer information to the application systems, operation devices, and activity manag-
WLAN environments
recording material details by hand On-site
Activity
materials
worker Information overload
System Device
Activity manager
ers. For the case study, the main cause of the communication barriers is the distance between the activity workers and application systems, since the activity workers are busy with material inspections and move away from the operation devices. 3. Information technologies for on-site information flow 3.1. Literature review In order to remove these barriers, applying information technologies (IT) to the examined on-site information flow may be useful. The key advantage of IT-based solutions is that the activity workers can avoid depending on memory while completing material reports [7]. The common IT applications include: Mobile computing: Mobile computing enhances project management by providing activity workers with different kinds of information relating to building standards, materials, activities, and reprocesses in working periods [8]. When staying at construction sites, activity workers and managers have the ability to complete many administrative jobs by using mobile devices. For example, Kuladinithi et al. [9] thought that wearable computing, along with advanced mobile communication, had the potential to revolutionize the working environment and processes of the mobile worker in the AEC industry. Kimoto et al. [10] integrated PDAs with construction management so that activity workers could flexibly process data at construction sites. Wang et al. [11] proposed a PDA- and RFID-based dynamic supply chain management system in construction projects. Bar-code system: This system uses optical scanners to capture the information stored in bar-code labels. The mapping between the captured information and the scanned bar-codes is called ‘‘symbology,” which is necessary to encode digits and characters [12]. For example, while scanning bar-code labels, activity workers can understand both the material name and the quantity. These will automatically be recorded into reports. Since activity workers simultaneously check materials and complete material records at construction sites, activity managers are able to obtain material reports quickly. A bar-code system can also be useful in reducing construction wastes [13]. Global positioning system (GPS): GPS is a satellite-based radionavigation system. There are 24 GPS satellites orbiting the earth and transmitting radio signals. When a radio signal travels from a satellite to a receiver, GPS measures the amount of time and calculates the distance to determine the location in terms of longitude, latitude, and altitude. GPS applications are commonly used at construction sites to keep track of vehicle locations and material transmission [14]. Radio frequency identification (RFID): RFID is an automatic identification solution that streamlines data recognition and information acquisition, operating in a manner similar to bar-codes. An RFID system is composed of an RFID tag and an RFID reader. An RFID tag comprises a small microchip and an antenna. Data are normalized as a unique serial number and stored in RFID tags. RFID tags can be read within the radio range of RFID readers. When a PDA connects with an RFID scanner, the RFID-enabled PDA becomes a powerful portable data collection tool [15,16]. Future material-tracking management systems may be able to provide site owners with the ability to determine activity progress and materials delivered, simply by walking around a site where all materials are identified and tagged using an RFID system [17].
Communication barriers
Fig. 1. The communication barriers for the examined on-site information flow.
Based on the above descriptions, various information technologies are unique and useful tools. However, the GPS technique is not suitable for the case study because this study does not track the
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location of material transport. For example, activity workers cannot use GPS applications to determine whether or not ongoing activities require materials. The other information technologies mentioned above do not remove the communication barriers described in this study either, because the activity workers still need to apply operation devices to acquire material details by hand. According to the research on document management systems, Zantout and Marir [18] suggested that an embedded intelligent agent could enhance information transmission and avoid future delay. When an information system supports direct two-way communication, the coordinated cooperation among the activity workers, application systems, and operation devices will be carried out [8]. Consequently, this study proposes an approach that will enable activity workers to exchange information with operation devices when they do not have the use of their hands. 3.2. Approach for improvement According to research [19], human beings can speak 280 words per minute; however, they can only key in 15 words per minute via PDAs and 50 words per minute through keyboards. Besides, activity workers can produce information via speech when busy with on-site activities. Since speech technology can provide flexible interactions, many researchers have used speech-enabled applications in several fields. For example, Reddy et al. [20] created a voice-operated information system for drivers; Goose et al. [21] proposed the voice portal and a web-hosted converter in order to enhance web accessibility; and Chen and Tsai [22] developed a speech-enabled system for electronic commerce network environments. Integrating a speech system with the examined on-site information flow seems to be possible. This study compares a speech system with bar-code and RFID systems (Table 1). The three information technologies all require different operation devices to recognize information. These operation devices can transfer information from construction sites to site offices via WLANs. However, two-way communication is difficult for bar-code and RFID systems. For example, activity workers can receive information from bar-code labels and RFID tags, but the labels and tags cannot receive information from activity workers. Since a speech system can actively confirm information with activity workers, these workers may receive information when they move away from operation devices. If the activity workers find erroneous data in the received responses, the system can automatically modify the data when the activity workers prompt the said system. Excluding necessary communication facilities (e.g., a headset), the system does not require any additional costs. Based on this comparison, for the case study, a speech system not only removes the communication barriers, but also satisfies the project cost requirements.
Table 1 The comparison among bar-code, RFID, and speech systems. Evaluation
Bar-code
RFID
Speech
How is information stored?
Bar-code labels Bar-code readers One-way
RFID tags
Voice
How is the stored information received? What is the communication relationship between activity workers and operation devices? How are errors modified? Can the solution transfer information within WLANs? Does the solution require additional costs?
RFID readers One-way
Electronic devices Two-way
Manual Yes
Manual Yes
Automatic Yes
Yes
Yes
No
To achieve speech communication between an activity worker and a speech system, three processes (‘‘automatic speech recognition,” ‘‘text to speech,” and ‘‘auditory recognition”) are necessary. Fig. 2 shows that a speech system will use speech recognition to analyze the received details when an activity worker gives oral commands; this process is called automatic speech recognition (ASR). The speech system will then provide the results to the activity worker through speech synthesis; this process is known as text to speech (TTS). After hearing the speech-format responses, the activity worker will know whether the commands have been executed correctly; this process is auditory recognition (AR) [23,24]. This communication procedure is similar to human conversations. Likewise, if an operation device clearly receives speech and a speech system correctly recognizes the speech, the activity workers will obtain greater working efficiency within the on-site information flow. Moreover, wireless technologies will be helpful for data transmission when there is the distance between activity workers and operation devices. Besides WLANs, the Bluetooth technique can assist activity workers in synchronous data exchange among different devices (e.g., mobile phones and hand-held computers). The short-range speech connections of walkie-talkie communication are the common Bluetooth applications, because the wireless link between different devices can reach 30 feet [25]. Consequently, the approach for improving the examined on-site information flow is to integrate wireless and speech technologies. 4. Approach implementation This study develops an exploratory system to implement the approach. A successful application system must integrate present requirements in a way that reduces the current burden while activity workers use the system for their normal tasks [7]. According to the actual working processes, this study completed the system development through three steps: ‘‘producing on-site information,” ‘‘confirming on-site information,” and ‘‘submitting on-site information.” 4.1. Producing on-site information For the case study, Fig. 3 shows the information transmission procedure between the activity workers and the exploratory system. In Step 1A, the activity workers described material details according to the classification of material records (such as an inventory record, a use record, and a requirement record). Table 2 shows material records, comprising the necessary data fields. The material inventory, use, and requirement records were composed of 7, 6, and 7 data fields, respectively. Previously, while receiving the sentence-format material details, the application system could not recognize this information. Therefore, the activity workers had to complete each required data field separately. The
Human
Machine
Speech
Automatic
commands
Speech Recognition (ASR)
Auditory
Text
Recognition
To
(AR)
Speech (TTS)
Fig. 2. The procedure for human–machine communication.
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Start
The activity workers
Step 1A:
The exploratory system
Step 1B:
material
Checking materials
Analyzing details
details analyzed results
Step 2B:
Step 2A: Confirming results
Modifying data
incorrect data
Database Step 3A: correct
WLANs
Submitting data
Step 3B: Saving
data
data
Recording
Completing
Next cycle
End
reports
another record
Switching to another report Fig. 3. The flowchart for the examined on-site information flow.
Table 2 The requiring data fields and sentence models for various material records. Record types
Data fields
Conjunctive words
Sentence models
Examples
Material inventory record
The seven data fields are: (1) defined material number; (2) material name; (3) material quantity; (4) storing location; (5) supplier name; (6) material test and (7) testing report number The six data fields are: (1) defined material number; (2) material name; (3) material quantity; (4) activity name; (5) activity location and (6) worker name The seven data fields are: (1 and 2) requirement date (month and day); (3) defined material number; (4) material name; (5) material quantity; (6) activity name and (7) activity location
‘‘delivers,” ‘‘of,” ‘‘to,” and ‘‘with”
Supplier name delivers material quantity of material name to storing location with material test testing report number
Jet company delivers six tons of steel to the first floor with no testing.
‘‘does,” ‘‘in,” ‘‘and,” ‘‘uses,” and ‘‘of”
Worker name does activity name in activity location and uses material quantity of material name
Tsai does wall repair in the third floor and uses two bags of cement
‘‘needs,” ‘‘of,” and ‘‘on”
Activity location activity name needs material quantity of material name on month day
The third floor wall repair needs ten bags of cement on September 5
Material use record
Material requirement record
inconvenient data input delayed the production of on-site information. However, these data fields can combine to form speech structures. For example, the activity workers fill the material name (steel) and quantity (ten tons) in the material reports, or, similarly, the activity workers can say ‘‘ten tons of steel”. Table 2 shows that this study constructed three sentence models (consisting of the data fields and conjunctive words). For completing various material records, the exploratory system stored the data fields and deleted the conjunctive words. For example, when creating a material inventory record, the activity workers could speak ‘‘jet company delivers 6 tons of steel to the first floor with no testing (sup-
plier name delivers material quantity of material name to storing location with material test testing report number)”. The data fields were ‘‘jet company (supplier name)”, ‘‘6 tons (material quantity)”, ‘‘steel (material name)”. ‘‘the first floor (storing location)”, and ‘‘no testing (material test)”, and the conjunctive words were ‘‘delivers”, ‘‘of”, ‘‘to”. and ‘‘with”. To ensure that the activity workers could smoothly describe material conditions via speech and the speech-format sentences could be recognized, this study integrated ‘‘grammar rules” and speech tags with the exploratory system. Grammar consists of sets of utterances (such as words and phrases) that are helpful for increasing the accuracy of speech recognition [26]. When the activ-
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ity workers accessed the material reports, the grammar rules and the defined vocabulary (such as the date, names, location, and workers required for the activity, the necessary materials, material suppliers, and the conjunctive words) were loaded onto the exploratory system. Fig. 4 shows the architecture of the exploratory system. In order to represent the Internet-based and speech-enabled material reports, this study used XHTML + Voice standard [26] and programming languages (e.g., ASP.Net [27] and JSP [28]) to build all system components. The Web server, which consisted of Microsoft Windows Server 2003 [29] and Microsoft IIS 6 [30], offered information exchange between the construction site and the site office. The database server (Microsoft SQL Server 2005 [31]) was another important component for storing all of the material data (including the vocabulary and records). Since the exploratory system combined speech functions and the existing Internet-based material reports, this study did not alter database frameworks and tables. When on-site information transferred from Step 1A to Step 1B (Fig. 3), the exploratory system automatically analyzed the received speech-format material details through ASR and TTS. The pronunciation and speaking behaviors of activity workers varied, and therefore influenced the accuracy of speech recognition. For example, in the case study all Taiwanese activity workers pronounced ‘‘sand” as ‘‘sa” or ‘‘sa-gi” in Chinese. The activity workers also had difficulty in remembering all defined material numbers. For better speech recognition, editing the relational calling names and corresponding numbers of same materials was a necessary process. While receiving the speech-format sentences from the activity workers, the exploratory system simultaneously identified the matching data and filled in the material reports. 4.2. Confirming on-site information After Steps 1A and 1B (Fig. 3), Step 2A shows that the exploratory system communicated the analyzed results to the activity workers through TTS. When hearing the speech responses, the activity workers could confirm whether the recognized and recorded data were correct. However, there is the possibility of unforeseen situations. For example, a spoken sentence did not contain all material details; the exploratory system did not completely recognize the speech entry; and the exploratory system produced erroneous data. In Step 2B, the activity workers modified the incorrect record with the exploratory system by using speech commands. For example, if the material quantity was incorrect, the activity worker could speak ‘‘quantity” to prompt the exploratory system. The system then asked the activity worker to repeat the material quantity.
XHTML+Voice documents
4.3. Submitting on-site information If the record was initially correct, or was corrected by the activity worker, Fig. 3 shows that the exploratory system submitted the material record through WLANs (Step 3A). When receiving the submitted record, the Web server saved the material data into the database (Step 3B). Finally, the activity workers could process other material records, switch to another material report, or exit the system to complete material reports. Clearly, the above on-site information flow was continuous even though there was the distance between the activity workers and the exploratory system throughout the working periods. In summary, Fig. 5 displays the improved on-site information flow when this study implemented the approach. WLAN environments offered the convenient platform for the information exchange and Bluetooth connections enabled the activity workers to communicate directly with the exploratory system and the operation device via speech. The exploratory system could intelligently recognize the inputted information, actively process the recorded results, and immediately submit the confirmed reports. The communication barriers identified in Fig. 1 were eliminated. The activity managers were able to understand the on-site material status even though the activity workers were not at the site office. 5. System tests After completing the system development, this study performed various system tests to determine whether the exploratory system could work in the case study. Five male activity workers (testers) participated in the tests and their age ranged from 27 to 32 years old. All testers had two to four years of experience in on-site material management, and one of the testers even participated in designing material reports. None of the testers had previous experience with speech-enabled applications, so they were trained to understand these communication methods. The three system tests were: Initial system tests: This study confirmed whether the testers performed speech communication successfully. When inspecting material status, each tester worked with 15 different material records (obtaining five inventory records, five use records and five requirement records) with the previous system (the activity workers completing material reports by hand) and the exploratory system (the activity workers completing material reports via speech) at the construction site. For example, the testers manually entered the data fields to complete a material use record in the previous system. For the exploratory system, they could finish the similar record via speech. Table 2 shows that the testers spoke ‘‘Tsai does wall repair in the third floor and uses two bags of cement (worker name does activity name in activity location and uses material quantity of material name)”. After automatically deleting the conjunctive words
(representing material records)
WLAN environments Activity worker
Microsoft SQL Server 2005
recording material details via speech
(storing material data) Web server: Microsoft Windows Server 2003 and IIS 6 (offering information exchange) construction site
On-site
Activity
System
materia
worker
Device
Bluetooth connections
site office
Fig. 4. The architecture of the exploratory system.
Fig. 5. The improved on-site information flow.
Activity manager
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(including ‘‘does”, ‘‘in”, ‘‘and”, ‘‘uses”, and ‘‘of”), the exploratory system stored the data fields (including ‘‘Tsai (worker name)”, ‘‘wall repair (activity name)”, ‘‘the third floor (activity location)”, ‘‘two bags (material quantity)”, and ‘‘cement (material name)”). System tests for communication barriers: The testers performed the system tests without carrying the laptops, because Bluetooth technology enabled information transmission within different distance environments. According to the test results, this study could confirm whether the communication barriers were removed when the activity workers moved away from the laptops. For example, although the testers did not touch the laptops, Table 2 shows that they completed a material requirement record by speaking ‘‘the third floor wall repair needs ten bags of cement on September 5 (activity location activity name needs material quantity of material name on month day)”. If the exploratory system successfully classified the data fields (including ‘‘the third floor (activity location)”, ‘‘wall repair (activity name)”, ‘‘ten bags (material quantity)”, ‘‘cement (material name)”, and ‘‘September 5 (month day)”) and the conjunctive words (including ‘‘needs”, ‘‘of”, and ‘‘on”), the communication barriers were overcame. Long-period system performance: This study chose one tester, having the best performance in the initial system tests, to apply the exploratory system in order to complete material reports for 14 working days. Based on the test results, this study could understand the differences between the previous and exploratory systems. During the period of system tests, the measuring items were: data fields, erroneous data, accuracy rate, operation time, and time efficiency. The long-term reliability of inputting data via keyboards was prone to human errors. Moreover, background noise remains a significant variable for the performance of a speech-enabled system. When the noise level exceeds 90 dB, humans are uncomfortable and have difficulty with auditory recognition [24,32]. To process speech and auditory recognition, the noise level of system tests was less than 80 dB. As incorrect material records were not useful for material management, the testers modified erroneous data, the process defined as the data modification and included the operation time. This study used Eq. (1) to determine the accuracy of information production:
fields errs 100% accuracy rate ¼ fields
ð1Þ
where the fields are data fields and the errs are erroneous data. In addition, a computerized approach for collecting site information could be recorded and processed to produce immediate feedback on the project status and problems [7]. The improved operation time certainly influenced the decision of the activity workers to apply a new computerized system. Eq. (2) was applied to identify the time efficiency:
time efficiency ¼
pre OT OTexp 100% OTpre
ð2Þ
where the OTpre is total operation time for the previous system and the OTexp is total operation time for the exploratory system. 6. Test results This study details the results of initial system tests (Table 3), system tests for communication barriers (Table 4) and long-period system performance (Table 5) in the following sections. 6.1. Initial system tests For the system tests in the previous system, Table 3 shows that testers 1, 2, and 4 spent 300, 295, and 303 s, respectively, correctly completing 15 material records (100 data fields). Although having incorrect inputs, testers 3 and 5 spent 300 and 304 s completing all records (including the data modification), respectively. Compared to key-in speed, the accuracy rate was not an absolute factor in the test results, since the testers did not spend much time modifying errors. For example, the operation time of tester 3 was similar to that of tester 1. When performing the same tests in the exploratory system, testers 2 and 3 spent 245 and 255 s on correctly completing the material reports, respectively. To modify the incorrect data, testers 1, 4 and 5 spent 273, 281 and 277 s on finishing all material records, respectively. For the exploratory system, the procedure of data confirmation was different from the previous system. The testers identified errors and used the exploratory system to reprocess speech recognition. The system responded by asking for the incorrect material record. Because the operation time accounted for the conversion time between the activity workers and the exploratory system, the operation time of testers 1, 4 and 5 was longer than that of testers 2 and 3. The average accuracy rates of previous and exploratory systems were 99.4% and 99%, respectively. When the average operation time of the previous system was 300 s and that of the exploratory system was 266 s, the average time efficiency reached 11.33% (Eq. (2)). Based on the average performance of system tests, the testers
Table 4 The system tests for communication barriers. Tester
Data fields
The exploratory system Errors
Accuracy rate (%)
Operation time (s)
98 100 97 99 100
288 265 303 279 271
1 2 3 4 5
100 100 100 100 100
2 0 3 1 0
Average
100
1.2
98.8
281
Table 3 The test results for initial system tests. Tester
Data fields
The previous system Operation time (s)
Errors
Accuracy rate (%)
Operation time(s)
100 100 99 100 98
300 295 300 303 304
2 0 0 2 1
98 100 100 98 99
273 245 255 281 277
9.00 16.95 15.00 7.26 8.88
300
1
99
266
11.33a
100 100 100 100 100
0 0 1 0 2
Average
100
0.6
300
100%.
Time efficiency (%)
Accuracy rate (%)
1 2 3 4 5
a ð300266Þ
The exploratory system
Errors
99.4
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M.-K. Tsai / Advanced Engineering Informatics 23 (2009) 323–331 Table 5 The test results for long-period system performance. Material records
The previous system
Day
Inventory
Use
Requirement
1 2 3 4 5 6 7 8 9 10 11 12 13 14
10 5 7 5 5 8 4 5 7 4 5 6 6 8
12 9 11 14 14 10 8 13 10 10 6 8 10 7
6 2 7 5 3 5 2 3 0 3 2 0 1 3
Total a ð173411Þ
1734 b ð173413Þ
1734
Errors
184 103 164 154 140 151 90 134 109 109 85 90 109 119
2 0 1 1 0 1 0 2 1 0 0 0 2 1
1734
11
Accuracy rate (%) 98.87 100.00 99.39 99.35 100.00 99.34 100.00 98.51 99.08 100.00 100.00 100.00 98.17 99.16 99.37a
The exploratory system Operation time (s)
Errors
523 306 480 452 410 450 267 397 319 323 252 263 323 353
2 1 0 2 3 0 0 1 0 2 1 0 1 0
5118
13
Accuracy rate (%) 98.87 99.03 100.00 98.70 97.86 100.00 100.00 99.25 100.00 98.17 98.82 100.00 99.08 100.00 99.25b
Operation time (s) 462 278 405 419 398 376 229 353 280 298 221 230 290 298 4537
Time efficiency (%)
11.66 9.15 15.63 7.30 2.93 16.44 14.23 11.08 12.23 7.74 12.30 12.55 10.22 15.58 11.35c
100%. 100%.
c ð51184537Þ
5118
Data fields
100%.
produced and delivered the on-site material information efficiently when performing the speech communication with the exploratory system. Overall, the testers were able to use speech to complete material reports with the exploratory system, integrating both Bluetooth and WLAN environments. 6.2. System tests for communication barriers This study had no test results when there were communication barriers in the previous system. The testers could not complete material reports when they were away from their laptops. For the exploratory system, auditory recognition and speech communication, rather than visual displays, were the main methods of two-way information exchange. When the laptops were placed on the floor, the testers could describe the material details via speech and complete material records at a distance up to 30 ft. Table 4 illustrates that testers 2 and 5 spent 265 and 271 s, respectively, completing material reports with the exploratory system. To modify the erroneous data, testers 1, 3 and 4 spent 288, 303 and 279 s finishing the system tests, respectively. The average operation time and accuracy rate were 281 s and 98.8%. Obviously, the testers successfully communicated with the exploratory system to complete the on-site material reports without having to carry the laptop. This study improved the communication barriers for the case study.
The initial test results in Table 3 show that the best operation time of tester 2 was 245 s for 100 data fields, using the exploratory system. Under this system, the ideal operation time for tester 2 would be 4248 s for 1734 data fields. As a result of 13 errors caused by speech recognition (Table 5), the actual executed data fields totaled 1747. Therefore, tester 2 spent 4537 s completing all material records. For modifying errors, the time difference (289 s) of the both actual and ideal operation time was understandable and reasonable. When the total accuracy rates of previous and exploratory systems were 99.37% and 99.25%, the time efficiency was 11.35% (Table 5). Fig. 6 shows that the cumulative time difference increased with the number of working days. For the long-period system tests, tester 2 produced speech-format material information conveniently and quickly. The confirmed material records were delivered into material reports automatically. To summarize, the exploratory system offered a better environment for the on-site information flow. 7. Discussions Based on the above descriptions, this study improved the examined on-site information flow. This study then compared the previous and exploratory systems, and classified their main differences. For project management, the advantages of the exploratory system are:
6.3. Long-period system performance This section of the study focused on long-period system performance. Tester 2, having the best test result in the initial system tests, applied the exploratory system in the on-site material management for 14 working days. According to the test results of the initial system tests for the previous system, Table 3 shows that the best operation time of tester 2 was 295 s for 100 data fields. In the 14 working days, the total requiring data fields of the previous system (Table 5) were 1734. The ideal operation time (defined as the assumed best operation time) would be 5115 seconds for completing all data fields. However, the total number of erroneous data items was 11, which increased the actual number of executed data fields to 1745. Since errors did not seriously influence the data modification, the actual operation time (5118 s) was close to the ideal operation time.
Information interdependence: On-site information immediately transferred from activity workers to operation devices and activity managers. This condition lessened information overload for the activity workers. The lack of real-time information for offsite data analysis was also improved. Since project participants obtained time and space to resolve any unexpected problems, they benefited from the interdependence of compact information. For example, the construction company had several ongoing projects in the case study. To save on material costs, the construction company ordered quantities of similar material from a supplier, based on the requirements. According to the details of the order, the supplier transported the material to the different construction sites. If the activity workers received an incorrect
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M.-K. Tsai / Advanced Engineering Informatics 23 (2009) 323–331
The previous system
The exploratory system
6000
atory system did not have an impact on the project cost and the database files. When activity workers applied the exploratory system at activity sites, this system required no additional costs.
Operation time (sec)
5000
When activity workers and managers applied other small-size devices (e.g., PDAs and smart-phones) for project management, the activity workers were able to access the exploratory system. The system also had the potential to be combined with other similar project reports and information flows. Considering the project losses caused by the lack of on-site information, the exploratory system was an efficient application. For example, if the cost of an activity laborer was USD 70 per day, the construction company lost USD 350 per day when a five-person activity was delayed by material shortages.
4000
3000
2000
1000
8. Conclusions 0 1
2 3
4
5 6
7
8
9 10 11 12 13 14
Day Fig. 6. The cumulative operation time for 14 working days.
quantity of the material, the activity managers and the construction company required real-time information (including material name, quantity, and supplier name) to contact the supplier. Enhancing relative project management: Activity workers and managers cooperated with various project participants for on-site activities. Immediate on-site information compactly connected the cooperation relationship, and ensured that the activity managers effectively allocated on-site resources. For example, although activity managers ordered five tons of steel some days ago, activity workers could not receive the steel on the required day, since material suppliers required time to prepare and transport the steel. If the activity managers discussed the delivery period with the material suppliers, the lack of steel could be resolved. The activity managers could also transfer the required steel from other construction projects, or revise the activity schedules. Proper human–machine collaboration: For most IT-based solutions, the human–machine collaboration required activity workers to face the application systems and operation devices. Comparatively, the exploratory system actively interacted with activity workers, even though the activity workers did not touch the operation devices. By reducing unnecessary movement between the activities and operation devices, the activity workers were able to focus on the ongoing processes. For example, in the case study, the activity workers inspected an activity and counted the remnant quantity of activity materials. When the activity workers reported the details, via speech, through Bluetooth headsets, the laptops recognized and transferred the receiving information even though the activity workers were not near the laptops. If the activity managers understood that the remaining quantity of activity materials was low, they could immediately discover the causes of the shortage, which might include incorrect activity processes, resource waste, or an erroneous order. The satisfying development and application cost: This study developed the exploratory system based on the reports in use and the existing information equipments. In other words, the explor-
For project management, activity managers require much information from numerous on-site information flows. Efficient information production and transmission between activity workers and application systems smooth the flow of on-site information. Although various IT-based solutions can assist activity workers in transmitting information, this study recognizes that communication barriers affect information production. The onsite information flow from activity workers to the activity managers was then interrupted. For example, this study examined a number of activities at construction sites. Since the activity workers were busy with activity processes and away from the operation devices, the activity managers could not obtain activity information. The construction company wasted resources on the activities. Consequently, this study applied an approach for the communication barriers and on-site information flow. In a material management case study, this study developed an exploratory system by integrating both wireless and speech technologies. During the period of system tests, the testers successfully used the exploratory system for completing material reports. The cost requirements for the system development and applications were satisfactory. Two-way communication between the testers and the exploratory system achieved the proper human–machine collaboration. The construction company and project participants benefited from information interdependence. For future research, this study will apply the exploratory system to similar issues in project management. Acknowledgements The author thanks Win-Chung Construction Corporation and all participants for this study. References [1] L.C. Bell, G. Stukhart, Attributes of materials management systems, Journal of Construction Engineering and Management 112 (1) (1986) 14–21. [2] D.U. Kini, Materials management: the key to successful project management, Journal of Management in Engineering 11 (1) (1999) 30–34. [3] R.M. William, J. Hal, Construction Jobsite Management, Delmar Publishers, New York, 1998. [4] N. Dawood, A. Akinsola, B. Hobbs, Development of automated communication of system for managing site information using internet technology, Automation in Construction 11 (2002) 557–572. [5] D.A. Pogorilich, The daily report as a job management tool, Cost Engineering 34 (2) (1992) 23–25. [6] A.D. Russell, Automated interpretation of job site records, in: Proceedings Second Congress of Computing in Civil Engineering, ASCE, Atlanta, 1995, pp. 989–996. [7] A.D. Russell, Computerized daily site reporting, Journal of Construction Engineering and Management 119 (2) (1993) 385–402.
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