A steel tank which is 2.0m by 4.5m by 3.0m is installed under the ground in order to investigate increase of heat extraction or heat injection by ground water flow in the ground thermal energy system (GTES). First, the authors define unit heat transfer rate, which can clarify relative merit of heat extraction or injection performance. Next, it was confirmed that the unit heat extraction rate increases according to the ground water velocity even in the case where the ground water velocity is relatively small (100〜350m/year). When the ground water velocity is 1400m/year, unit heat transfer rate with a double pipe ground heat exchanger is 16.12W/m/K and more than three times larger than the one with a single U-tube ground heat exchanger. The result shows that using a ground heat exchanger with small internal thermal resistance is effective to increase the heat extraction from the ground. In addition, from the result that the unit heat transfer rate of measuring was larger than the one calculated with considering only forced convection, it was indicated that the free convection is generated in the sand layer. Thus the authors investigated about the effect of the mixed convection.

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Solar water heater is an useful heat source for the desiccant cooling because it is clean, renewable and has a low cost. This paper mainly discusses about the influences of cooling load and air change rate of a room on the performance of the desiccant cooling system consisted of a desiccant wheel, thermal wheel, two evaporative coolers, a cooling coil, flat plate solar water heater, and air heater. The cooling system is assumed to be applied to an office room of 250m^3 in volume. Produced dehumidifying performance per unit air volume by the desiccant cooling process decreased with increase in sensible cooling load since the regeneration air temperature decreased due to simultaneous increase of the amount of regeneration air flow and flow rate of water circulating in the solar water heater. However, temperatures of hot water and regeneration air supplied from solar water heater of 20m^2 was high enough to produce a sufficient dehumidifying performance per unit time even in the total cooling load of 22.2kW and SHF=0.9 since the increase in the amount of process air flow compensated the decrease in dehumidifying performance per unit air volume. On the other hand, required amount of dehumidification per unit time increased as the SHF value decreased. Therefore, temperature of hot water supplied from solar water heater of 20m^2 did not reach a sufficient level for the indoor air condition at SHF 0.65 and 12kW the sensible heat load. In this case, additional heat input between 1.7 and 20.0kW was required depending on the amount of solar heat obtained by the solar water heater. The ratio of cooling power produced by the desiccant cooling process to the total cooling power of the whole of the cooling system (desiccant cooling process+cooling coil) was around 0.2-0.3 when the SHF value was 0.65 since the obtained dehumidifying performance was just enough to satisfy the required humidity for the room. On the contrary, required dehumidifying performance became small when the SHF value was large and desiccant cooling could produce a surplus dehumidifying performance resulting in a sensible cooling effect of the evaporative cooler. Thus the required cooling power of the cooling coil became lower at higher SHF condition. Influence of the air change rate on the performance of the cooling system was also investigated. The ratio of cooling power produced by the desiccant cooling process increased in higher ventilation rate since the required amount of dehumidification became larger. However, the ventilation rate had no effect on the required cooling power of the cooling coil, for the inlet air temperature of the regeneration side became lower resulting in low temperature dry air at the process outlet of the thermal wheel.

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A hourly utility demand such as electricity, gas and hot water derived from the time-varying inhabitants' behavior schedule that is generated through the authors' method is compared with the real observed of a residential building having 18 family units in Fukuoka. In the prediction process, a package of fundamental unit assumptions for how much an inhabitant consumes energy in each behavior is used as same as our previous works. It has been proved that the predicted hourly demand acceptably agrees with the real observed data.

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The protection of non-smokers against tobacco smoke is a common subject in many countries. In Japan, the health promotion law to restrict environmental tobacco smoke (ETS) in public places was passed in 2002. Since then, public places such as train stations and government office buildings have been divided into smoking and non-smoking areas. However, in restaurants and pubs, these preventive actions against ETS have been inadequate and ineffective. In this paper, measurements of the particulate material in restaurants and smoke visualization are conducted to study the influence of tobacco smoke. The measured restaurant is located in residential areas (Yokohama, Japan), where young people and their children face the ETS risk in restaurants. In the first part of this paper, the measurements taken in one restaurant are presented. The following are the contents of the measurements: (1) Measurement of particulate matter concentration in smoking and non-smoking zones. (2) Visualization of the air flow between smoking and non-smoking zones. In the second part of this paper, a computational fluid dynamics (CFD) simulation is carried out to reproduce the measurement conditions in the restaurant. Several ventilation systems to improve the air quality in non-smoking areas are studied by CFD case studies. According to the results of the measurements and CFD case studies, the relative location of smoking section and inlet/outlet for ventilation influences significantly on the effect of separation of non-smoking and smoking areas.

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