Yasushi Yoshimura

PROGRESS CONTROL METHOD USING THE KNOWLEDGE OF SKILLED MANAGER ON CONSTRUCTION STAGE IN PLANT CONSTRUCTION

This paper presents a computer system supporting progress control. The system incorporates the knowledge of skilled construction managers about methods of forecasting the actual status and future status of plant construction progress. First, a construction site model is developed to forecast actual status and future status of construction progress using the current status of the construction site. For the construction site model, the input is factors that describe the status of the construction site, and the output is accomplishment and man-hours. Eleven factors describe the status of the construction site, including qualitative factors. For example, one of the qualitative factors is work efficiency. The factors are determined by analyzing the knowledge of skilled managers. The degree of influence between these factors, and accomplishment and man-hour, is determined by the Analytical Hierarchy Process (AHP) method. As a result, a method which can quantify the influence of these factors and forecast the variation of accomplishment and man-hour using this construction site model, is established. A skilled manager evaluated the values output from the computer system using this method, and the results proved that the system is effective for progress control.

Development of Work Traceability System Using RFID Technology in Plant Construction Management

Abstract: In this study, we evaluate the applicability of RFID tags and developed material management system and the work traceability system in plant construction. The examination results indicate that RFID tags and GPS systems were usable enough. About the work traceability, we solved administrative problems of the digital photographs and suggested a method to prove an original or an imitation of the digital photography. And, it was able to reduce time to search for construction materials by the developed systems and time to make a report using digital photographs.

An electronic sound cancellation system for air‐conditioning ducts

Recently, research on an electronic sound cancellation system that is able to cancel noise using sound of the opposite phase has been conducted. This kind of noise control technique is referred to as active noise control (ANC). In order to realize a practical working ANC system, it has been considered desirable to apply the LMS (least‐mean‐square) algorithm to such a systems control, especially the VS (variable step)‐LMS algorithm due to its high speed of convergence. The realization of an ANC system of the stand‐alone type is presented. Experiments were conducted in actual air‐conditioning ducts having a cross section of 500 × 500 mm by using the realized stand‐alone type active noise control system with the VS‐LMS algorithm. Below the cross‐mode frequency, more than 15 dB of attenuation was obtained for broadband random noise, even in the presence of an air flow of 3.7 to 9.0 m/s.Recently, research on an electronic sound cancellation system that is able to cancel noise using sound of the opposite phase has been conducted. This kind of noise control technique is referred to as active noise control (ANC). In order to realize a practical working ANC system, it has been considered desirable to apply the LMS (least‐mean‐square) algorithm to such a systems control, especially the VS (variable step)‐LMS algorithm due to its high speed of convergence. The realization of an ANC system of the stand‐alone type is presented. Experiments were conducted in actual air‐conditioning ducts having a cross section of 500 × 500 mm by using the realized stand‐alone type active noise control system with the VS‐LMS algorithm. Below the cross‐mode frequency, more than 15 dB of attenuation was obtained for broadband random noise, even in the presence of an air flow of 3.7 to 9.0 m/s.