Researchershave just begun to evaluate the role of such non-conventional data in construction applications. This paper discusses the development of a prototype system that deals with audio/ visual information along with other types of data in support of project management. 0 1997 Elsevier Science Limited. All rights reserved. Key words: audio data, visual data, construction management, database, information system, project management, pictorial information. INTRODUCTION Adequate and effective management of construction projects depends on good access to and control of data, especially data pertaining to the performance of a construction project. ‘12 Long recognizing the need for quality information, researchers have proposed data models to achieve the desired acquisition, storage and presentation of (data and information. 3 However, one such type of information, namely audio/visual, has long been neglected or not appropriately acquired, stored, processed and ,presented.
The proper design of an automated solution has been lacking that would provide access to audio/visual data in support of project management. Therefore, the primary objective of the research project discussed in this paper is to develop an automated audio/visual information management system that is integrated into the construction project control process, particularly performance evaluation and delay management, to improve the quality of information for project management. Pictorial information (pictures and video tapes) should play an important role in construction management.
Some construction companies require that appropriate field personnel (a superintendent or a foreman) take pictures of layouts and situations (such as critical activity or an activity with a new construction method) 97 that the company feels need attention or special observation. 4 A list of potential applications of pictorial information in construction can be found in Ref. 5. In analysing the benefits of such applications, it has become clear that visual information is very useful in construction. However, the acquisition or management of this type of information is lacking or inappropriate.
Therefore, the proper design of an automated system for the data acquisition and storage of this type of data should encourage contractors and owners to take pictures more often than current practice. By such automation, pictures will become an important reported item. Performance evaluation will depend on both numeric and visual reports in contrast to current practice that depends on numerical reports only. Furthermore, adding digitally stored audio comments on the activities in the various control accounts should provide additional details to the different reports.
This paper, therefore, addresses a key issue that is needed in achieving effective project control: the proper design of an automated system for the acquisition, storage and retrieval of audio/visual data. Additionally, integrating the audio/visual database into the overall project control information system is addressed in the paper. Such integration is necessary for effectively using such non-conventional data in the overall project control process. 98 2 MFZHODOLOGY 0. Abudayyeh l Static database 1. ontrol-A~o~t-Budget-Mate~als This paper discusses a research project that addresses construction performance evaluation and delay management. To develop an automated and integrated solution for the management of audio/visual data in support of performance evaluation and delay management, a fourstep process, briefly described below, was used. ’ Step 1: The first step in the modelling effort, problem definition, involves identifying the data items needed and describing the behavior of the system with respect to the methods and mechanisms used in acquiring, storing and processing data.
Step 2: The second step, conceptual modelling, is a formal representation of the problem formalized by step 1. The outcome of this step is a conceptual data model that represents the design of the system and demonstrates the integration of audio/visual information with other project management data. Step 3: The third step, computational modeling, takes a conceptual data model from step 2 as input and transforms it to a computational model (such as the relational, hierarchical or network) suitable for implementation in automated environments.
Step 4: The fourth and final step of the modeling process,computer modeling, takes the computational model as input and maps it onto a computer data model that represents the automated computer system solution to the problem. l (Control- Account-Code, Material-Code, Quantity) 2. Control-Account-Budget-Hours (Control-AccountCode, Craft-Code, Man-Hours) 3. Control-Account-Budget-Equipment (ControlAccount-Code, Equ~ment-Code, Work-Hours) 4. Delay-Types (Delay-Type-Code, Desc~ption) Dynamic database 1. Delay-Record (Control-Account-Code, Date, Delay -Type-Code, Status) 2.
Control-Account-Audio/Visual-Info~ation (Controy-Account-Code, Data, Visual-Record, Audiorecord) 3. Control-Account-Actual-Materials (ControlAccount -Code, Date, Quantity) 4. Control-Account-Actual-Equipment (ControZAccount-Code, Equipment-Code, Date, WorkHours) 5. Control-Account-Actual-Hours (ControZ-AccountCode, Worker-ID, Date, Regular-Hours OP, Overtime-Hours OP) l ~istoriGa~ database THE DATABASE SCHEMA In developing the database schema for the audio/visual information system, the four-step modeling process described earlier was used.
The first two steps yielded a graphical representation of the information system using a modeling methodology called NIAM. 6 Then, the NIAM model was transformed into the relational database schema (step 3 of the modeling process). This section discussesthe relational database schema of the information system that resulted from step 3. During the relational database scheme design, three groups of relations were developed. The first group, called the static ~t~ase, includes the relations that deal with such data as budgets, definition of the work breakdown structure and activity network definition.
The second group, called the dynamic database, includes the relations that deal with the daily data and information acquired by field personnel on resource and time cons~ption. The third group, called the h~tori~a~ database, includes the relations that deal with the creation of historical data records for future reference. The following is a partial list of the relations in each database. 1. Control-Amount-Historical-Hours (ControlAccount-Code, Craft-Code, Regular-Man-Hours, Overtime-Man-Hours, Regular-Cost, OvertimeCost) 2. Control-Account-Historical-Materials (ConfrolAccount-Code, material-lode, Quantity, Cost) 3.
Control-Amount-Histori~I-~uipment (ControfAccount-Code, Material-Code, Work-Hours, Cost) 4. Delay-History (Control-Account-Code, DelayType-Code, Duration, Action, Visual-Record) 4 SYSTEM ~C~E~URE DEVELOPMENT AND The hardware components of the prototype system, shown in Fig. 1, include a video camera, a microphone, a video-capture board (frame-grabber), a sound card and a 486based computer workstation. The video camera, along with the frame-grabber, serves as the pictorial data acquisition mechanism. The camera has Fig. 1. Hardwarecomponents. Audio/visual information in construction project control
Fig. 2. System architecture. time-lapse capabilities to allow for compressing an 8-h shift into a number of shorter durations (e. g. 2 h). The microphone, along with the sound card, serves as the audio data acquisition mechanism. Once the desired activities in a control account are captured on video tape, the scene is digitized by connecting the camera (which serves as a video player) to the frame-grabber that is installed on the computer Fig. 3. An extract of the control-account-audio/visual-information report. 100 0. Abudayyeh the database record.
This mechanism stores each piece of data twice on the hard disk. In the second mechanism, a link to the physical location of the digital audio or image data file is stored in the database. Thus, less storage is needed. Therefore, the link mechanism is selectedfor storing digital audio and visual data in this prototype implementation. Processing and representing data in the prototype system is accomplished by using the report generator utility of the Access DBMS, which utilizes the standard Structured Query Language (SQL) for data definition and data manipulation.
An example report produced by the prototype system is discussed in the following section. 5 DATA PROCESSING AND REPRESENTATION workstation, and stored on the hard disk in a digital format. A number of visual data formats are available for storing digital image(s). A scenecan be captured in one of two methods: a sequenceof frames (video clip) or individual images (still pictures). Next, voice messages describing each control account are digitally captured using the microphone that is connected to the sound card along with an audio software package that creates digital audio files from voice signals.
After the digital voice and image acquisition processes are complete, the audio and visual data are stored in the relational database for processing and reporting. The Accessrelational database management system (DBMS) software package is used for implementing the prototype system. Figure 2 shows the system’s architecture and schematically displays the overall process of capturing, storing and reporting pictorial and audio information. A mechanism for storing digital image and audio data is the database is needed.
The Access DBMS supports two different storage mechanisms. In the first one, the digital audio or image data is physically embedded in In this section, the Control-Account-AudiolVisualInformation report, shown in Fig. 3, is discussed. It is an on-screen audio/visual information display for the Fig. 4. An extract of the control-account-audio/visual-information report (with video player utility). Audio/visual information in construction project control 101 various control accounts.
The Control-Account-Audio/ Visual-Znformatio,rz report has five fields: the controlaccount code (CACode), the date of the record (Date), the description of the control account (Description), a visual record in the video-clip format (Visual), and an audio message (Audio). Once the user executes this report, it is displayed on the screenin the form shown in Fig. 3. (Note that the figure is printed from a bit-map screen-dump file. ) To view the video clip in the Visual field, the user needs to double click on the displayed image to activate a video player utility that can play the video clip.
The video player utility is shown in Fig. 4. To listen to the audio messageassociated with this record, the user needs to double click on the microphone icon displayed in the Audio field, which will activate the audio player that plays the message. Note that each record is displayed in one screen. The scroll bars along the side and at the bottom are used to navigate through the various records in this report. 6 CONCLUSIOlNS data with project control data provides a powerful and effective project control system. ACKNOWLEDGEMENTS
The work presented in this paper was funded in part by the Office of Graduate Studies and Research and in part by the College of Engineering and Architecture at North Dakota State University. Their support is gratefully acknowledged.
REFERENCES 1. Abudayyeh, 0. Y. & Rasdorf, W. J. , The design of construction industry information management systems. J. Constr. Engng. Man. , 1991, 117, 698-715. 2. CII, the Construction Industry Institute, Project Control for Construction. Bureau of Engineering Research, the University of Texas at Austin, Publication 6-5, September 1987. 3. Rasdorf, W. J. & Abudayyeh, 0. Y. Cost and schedule control integration: issues and needs. J. Constr. Engng. Man. , September 1991. 4. Oglesby, C. H. , Parker, H. W. & Howell, G. A. , Productivity Improvement in Construction. McGraw-Hill, New York, 1989. 5. Abudayyeh, 0. Y. , The modeling, design and implementation of a construction multi-media information management system. Technical Report CME-95-01, Construction Division, Department of Civil Engineering and Construction, North Dakota State University, Fargo, ND, August 1995. 6. Rasdorf, W. J. & Abudayyeh, 0. Y. , A formal approach to schema design for engineering databases. J. Adv. Engng. Software, 1992, 14, 23-32. The information management system described in this paper strongly promotes the role of audio/visual data in the construction environment by developing and testing the concept of automated acquisition, storage and reporting of pictorial and voice data in support of project management. Therefore, the system produces fast, accurate visual and audio information about the progress on the site by providing instant pictorial data and verbal description capture. Thus, performance can be evaluated on time, and problem areas detected as they occur. Furthermore, the integration of audio/visual