The conventional transfer matrix models of fluid elements were modified and a convenient method of dealing with junction boundary conditions was introduced. A large scale fluid network was modeled by standard procedur...The conventional transfer matrix models of fluid elements were modified and a convenient method of dealing with junction boundary conditions was introduced. A large scale fluid network was modeled by standard procedures, and a network was expressed with characteristic matrix and boundary condition matrix. By simple operation of matrix, the dynamic characteristics of a large scale fluid network was simulated in frequency domain. Validation test on a large scale pipeline network showed that the proposed method is accurate and practical.[展开更多
Indoor microbial monitoring is an important health issue in many sectors of society. In particular, it is important to monitor microbial concentrations in environments dealing with bio-susceptible products. Many human...Indoor microbial monitoring is an important health issue in many sectors of society. In particular, it is important to monitor microbial concentrations in environments dealing with bio-susceptible products. Many human diseases are related to high, undesired microbial airborne concentrations. However, the lack of a standardized and well-accepted methodology for testing and ranking the performance of microbial air samplers is a source of uncertainty in such measurements. Several works clearly show that results obtained from microbial air sampling depend largely on measuring techniques, especially the air sampiers' physical parameters, such as d50, as well as environmental conditions, sources, and concentrations of microbial organisms in the environment. Furthermore, personnel using cleanroom clothing can reduce the microbial burden within a clean environment. To evaluate this effect, we carried out experimental comparison tests in a cleanroom of class ISO 5 with different air samplers under various microbial concentration levels, generated by a human source dressed in different quality cleanroom clothing. Our results confirm that in addition to the measuring technique, cleanroorn clothing does influence microbial contamination, affecting air samoler measurements.展开更多
文摘The conventional transfer matrix models of fluid elements were modified and a convenient method of dealing with junction boundary conditions was introduced. A large scale fluid network was modeled by standard procedures, and a network was expressed with characteristic matrix and boundary condition matrix. By simple operation of matrix, the dynamic characteristics of a large scale fluid network was simulated in frequency domain. Validation test on a large scale pipeline network showed that the proposed method is accurate and practical.[
文摘Indoor microbial monitoring is an important health issue in many sectors of society. In particular, it is important to monitor microbial concentrations in environments dealing with bio-susceptible products. Many human diseases are related to high, undesired microbial airborne concentrations. However, the lack of a standardized and well-accepted methodology for testing and ranking the performance of microbial air samplers is a source of uncertainty in such measurements. Several works clearly show that results obtained from microbial air sampling depend largely on measuring techniques, especially the air sampiers' physical parameters, such as d50, as well as environmental conditions, sources, and concentrations of microbial organisms in the environment. Furthermore, personnel using cleanroom clothing can reduce the microbial burden within a clean environment. To evaluate this effect, we carried out experimental comparison tests in a cleanroom of class ISO 5 with different air samplers under various microbial concentration levels, generated by a human source dressed in different quality cleanroom clothing. Our results confirm that in addition to the measuring technique, cleanroorn clothing does influence microbial contamination, affecting air samoler measurements.