There have been growing demands for intelligent design support systems that generate various plans for designers. Allocation of machines in a machine room is a combinatorial optimization problem under multiple criteria, such as cost, maintainability, order/neatness, etc. This study is aimed at realizing an integrated design support system for generation of layout/work drawings for machine rooms. This paper presents a new method for generating layout plans, which is the core of this integrated system. This method employs interactive evolutionary computation for incorporating designer's experience/know how into the plans. For reducing the designer's burden of interaction, this paper proposes (1) a coding method that encodes machine groups and (2) Pareto optimal search with tentative evaluation criteria. Experimental results with an actual scale problem demonstrate the feasibility of the developed system.

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A numerical model of PCM dealing with its melting-freezing process was introduced and examined its performance comparing with some theoretical and numerical results. It is proved that the PCM numerical model gives exact predictions. In order to investigate the effect of PCM wallboard on the indoor thermal environments, the PCM numerical model was incorporated into a CFD code developed by authors. Using the CFD code, some thermal performance of PCM wallboards was compared with ordinary gypsum wallboards with a standard type residential house assuming a summer cooling season. It was confirmed that the calculated results was acceptable and that the room thermal temperature in case of PCM wallboard was lower than that in case of gypsum wallboards.

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Temperature-stratified type has a little chance to be adopted as a thermal storage tank except in large-scale buildings because this type was considered to need rather deep tank though it has a high thermal storage performance. Recently several systems of this type have been applied to buildings having double-slab spaces under their basement floors by connecting shallow sub-tanks in parallel. However, the unbalance of stored heat in each tank connected in parallel has become a problem. In this study, an input/output apparatus was developed to realize a uniform inflow/outflow rate, and its performance was confirmed through experimental study. And, the effect of connecting holes bored in tank partitions on improving the unbalance of stored heat was studied experimentally, and the application result to an actual building was also reported.

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It is time for houses to group and play their roles in waste management in order to support material recycling. As the first step we investigated the waste composition thoroughly in part 1. To promote separate collection, facilities around houses and economic instruments can be introduced. Through the questionnaire delivered to residents and students living in Tokyo and neighboring prefectures, essential factors for separate collection, and specifications and requisites for storage, waste collecting stations, recycling centers were grasped. The effects of deposit systems were also analyzed with conjoint analysis method. If such conditions were fully fulfilled, consumers are ready to separate 70-80% of materials to recycling.

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The natural convection around an occupant body caused by its metabolism was examined how it influences on ventilation. The research object was a small office room with one or two occupants. The examination was performed with a water tank. The Reynolds number and Grashof number in the tank were equalized to those of the research object to simulate the forced ventilation and the natural convection, respectively. Ventilation efficiency indexes were calculated from the temperature change in the tank which was caused by the heated occupant's model. The examined ventilation patterns were downward and upward ventilations and wall bottom supply. The inlets and the outlets were examined with and without diffuser plates. The tested ventilation numbers were ranged from 0.5 to 10 air changes per hour. The applicability of the water tank method, which failed in simulating the Prandtl number of the real object room, was examined by comparing the ages of air in the present experiment with the experimental results of real rooms in existing literatures. The water tank method was found to be applicable because the ages of air in the method and the real room agreed reasonably well. The influence of the natural convection was tested by introducing two ventilation efficiency indexes. One of which was a heat direct evacuation ratio (HDER). This index indicates the rate of the produced heat, which did not mixed in the tank water. The second index was a ventilation bypass ratio (VBPR). This index suggest the rate of the ventilation flow, which did not contribute to transport the heat out of the tank. The downward ventilation of an air change number of larger than three ach had a negative HDER, and a positive VBPR. This indicates that the natural convection stagnated in the upper part of the tank, and difficult to be evacuated by the ventilation. The upward ventilation had a positive HDER and a negative VBPR throughout the examined ventilation numbers. natural convection concentrated in the upper part of the tank and evacuated smoothly by the ventilation. On the other hand, the supplied ventilation was blocked by the natural convection layer to reach the ventilation outlet in this flow pattern. The thermal stratification was clearly observed in the test of the lower ventilation numbers. The thermal stratification was broken by the entrainment flow of the forced ventilation as the ventilation number increased. The wall bottom supply indicated almost the same characters to the upward ventilation. In the later two ventilation patterns, the natural convection was found to keep its influence in transporting the heat to the ceiling outlets, and evacuated the occupant body heat directly, even when the thermal stratification was broken in a ventilation number of 8 ach.

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Under warm conditions, ceiling fans and cooling panels provide an inexpensive method for improving human thermal comfort. It is expected that ceiling fans and cooling panels controlled automatically according to thermal comfort indices can keep occupants' thermal comfort at a certain level, even under changing conditions. In this paper, two indices used for control were evaluated. One was the PMV and the other was the mean body temperature (Tmb) simulated with the 2-node model. Based on experiments with eight human subjects, the study showed that a ceiling fan system controlled according to the PMV could maintain a neutral thermal sensation in a transient environment. The Tmb-controlled ceiling fan system was not better than the PMV-controlled system. The PMV-controlled cooling panel system worked well for subjects' thermal sensation and comfort, whereas the Tmb-controlled cooling panel system could not maintain a stable ambient temperature. Subjects' thermal sensation fluctuated according to the swing of the ambient temperature. The combined system of a ceiling fan and a cooling panel was proposed as a better solution: the draught caused by the ceiling fan and the slow response of the cooling panel under changing conditions. The control of the combined system was based on the PMV. The air speed under the ceiling fan that was usually kept at 0.8m/s for energy saving, resulted in more than 80% of the subjects finding the conditions acceptable in the ceiling fan experiment. The cooling panel was controlled to be PMV=0, assuming that the air speed was 0.8m/s. The ceiling fan was controlled to increase or decrease the air speed from the 0.8m/s for rapidly changing conditions. The combined system kept subjects' thermal sensation neutral, and maintained subjects' thermal comfort. The PMV proved to be a good index to control devices to maintain occupants' thermal comfort, except when the occupants' thermal sensation deviated too much from thermal neutrality, e.g. immediately after the devices were started, or just after the occupants entered from outside.

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This paper describes experiments and analyses on an improved underground heat exchanger by using a no -dig method for the purpose of the cost reduction of a space heating and cooling system using underground thermal energy. First of all, the improved underground heat exchanger was installed on the campus of Hokkaido University, and it was shown that a ground source heat pump system utilizing the heat exchanger was sufficient for space heating and cooling. Secondly, evaluation program of the heat exchanger was developed, and the program was verified to give good predictions by comparing with experimental results. As a result of system simulations, an energy reduction for a system installation relative to a conventional vertical earth heat exchanger reached 78%. The primary energy reduction rate including the system installation and operation relative to a typical air source heat pump was 29%.

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The fungi in hesitation cause an allergic disease, degradation of house and etc, and influence our life. Many microbiological study about fungi had been reported, but there are few reports about fungi in hesitaion. In this study, to understand the ecology of fungi in hesitation, the test about growth conditions, ultraviolet ray resistance and medicine resistance of fungi, examined. In this test, we used 22 kinds of fungi isolated from hesitation. The result shows that the fungi in hesitaion are adaptable to variable condition, and we propose the prevention of fungal contamination.

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This study aimed to understand regional heat discharge by means of thermal system analysis that considered the ratio of cooling heat source devices derived from a completed database of building equipment. The results showed a clear relationship between floor space and the ratio of latent heat to total heat released from air conditioning systems and related devices. This may have been due to the effect of cooling towers, which are mainly used in large buildings. The total amount of sensible heat released from air conditioning systems and related devices in the 23 wards of Tokyo was estimated using the GIS database of floor spaces. The results showed that summertime sensible heat in the 23 wards of Tokyo reached 13-14GW in the daytime, and 180GW・h per day. In addition, latent heat that was released from air conditioning systems and related devices in the 23 wards of Tokyo accounted for 25-28% of total daytime heat in the summer.

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A commercial clothing dryer in a bathroom operates in such a way that heated air in a bathroom is circulated and dries clothes, while the evaporated moisture is discharged outside of the room. The drying process of the system was studied in experiments, and a simulation was done in terms of the drying process time and the following results were obtained. (1) The simulation employed an equation for the heat and mass transfer of clothing, and conservation equations for the energy and moisture mass in a bathroom. The simulation, which takes account of the shift from a constant drying rate to a reduced rate during the drying process, agreed well with the experiment. (2) The effects of the ventilation flow rate, the heat input and the ambient temperature on the drying process time were studied by the simulation. It was found that an optimum ventilation flow rate exists for the combination of the heat input and the ambient temperature.

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This paper reports the measurement results of settled particulate matter contaminated with fungi in air ducts before and after air duct cleaning. This study also gives a method for estimating the number of settled particles on the inner surface of air ducts using the index of areal coverage of settled particles. The main results are shown as follows: (1) Settled particles increase at an exponential function annually. Although there are about 42000 fungi contaminated in one gram weight of settled particles, they are almost removed by air duct cleaning together with settled particles. (2) The size distribution of settled particles both in supply and return air duct seems to be lognormal. (3) The number of settled particles can be estimated using "areal coverage index" of particles, and the estimated values correspond with the measured ones.

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