A multilayer one-dimensional canopy model was developed to analyze the relationship between urban warming and the increase in energy consumption in a big city. The canopy model, which consists of one-dimensional diffusion equations with a drag force, has three major parameters: building width, distance between buildings, and vertical floor density distribution, which is the distribution of a ratio of the number of the buildings that are taller than some level to all the buildings in the area under consideration. In addition, a simplified radiative process in the canopy is introduced. Both the drag force of the buildings and the radiative process depend on the floor density distribution. The thermal characteristics of an urban canopy including the effects of anthropogenic heat are very complicated. Therefore, the focus of this research is mainly on the basic performance of an urban canopy without anthropogenic heat. First, the basic thermal characteristics of the urban canopy alone were investigated. The canopy model was then connected with a three-dimensional mesoscale meteorological model, and on-line calculations were performed for 10 and 11 August, 2002 in Tokyo, Japan. The temperature near the ground surface at the bottom of the canopy was considerably improved by the calculation with the canopy model. However, a small difference remained between the calculation and the observation for minimum temperature. Deceleration of the wind was well reproduced for the velocity at the top of the building by the calculation with the canopy model, in which the floor density distribution was considered.
A coupled model consisting of a multilayer urban canopy model and a building energy analysis model has been developed to investigate the diurnal variations of outdoor air temperature in the office areas of Tokyo, Japan. Observations and numerical experiments have been performed for the two office areas in Tokyo. The main results obtained in this study are as follows. The coupled model has accurately simulated the air temperature for a weekday case in which released waste heat has been calculated from the energy consumption and cooling load in the buildings. The model has also simulated the air temperature for a holiday case. However, the waste heat from the buildings has little influence on the outdoor temperatures and can be neglected because of the low working activity in the buildings. The waste heat from the air conditioners has caused a temperature rise of 1°-2°C or more on weekdays in the Tokyo office areas. This heating promotes the heat-island phenomenon in Tokyo on weekdays. Thus, it is shown that the energy consumption process (mainly with air conditioning) in buildings should be included in the modeling of summertime air temperature on weekdays in urban areas.
[reaction: see text] On the basis of an efficient Pd-catalyzed triarylation to a vinylsilane platform, four types of structurally well-defined triarylethene-based extended pi-systems have been prepared very rapidly. From a compound library constructed by the present method, it was possible to find a number of interesting fluorescent materials, as well as interesting fluorescent properties such as aggregation-induced enhanced emission. A useful method for the rapid synthesis and property evaluation has also been developed.
Two well-known centrifugal and axial pumping principles are used simultaneously in a new blood pump design. Inside the pump housing is a spiral impeller, a conically shaped structure with threads on the surface. The worm gears provide an axial motion of the blood column through the threads of the central cone. The rotational motion of the conical shape generates the centrifugal pumping effect and improves the efficiency of the pump without increasing hemolysis. The hydrodynamic performance of the pump was examined with a 40% glycerin-water solution at several rotation speeds. The gap between the housing and the top of the thread is a very important factor: when the gap increases, the hydrodynamic performance decreases. To determine the optimum gap, several in vitro hemolysis tests were performed with different gaps using bovine blood in a closed circuit loop under two conditions. The first simulated condition was a left ventricular assist device (LVAD) with a flow rate of 5 L/min against a pressure head of 100 mm Hg, and the second was a cardiopulmonary bypass (CPB) simulation with a flow rate of 5 L/min against 350 mm Hg of pressure. The best hemolysis results were seen at a gap of 1.5 mm with the normalized index of hemolysis (NIH) of 0.0063 +/- 0.0020 g/100 L and 0.0251 +/- 0.0124 g/100 L (mean +/- SD; n = 4) for LVAD and CPB conditions, respectively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.