This study examined whether the efficiency of resting egg production of the marine rotifer Brachionus plicatilis is improved by employing the semi-continuous culture method. Rotifers were cultured in 0.5m³ polycarbonate tanks for 17-23 days by feeding frozen and concentrated Nannochloropsis oculata. An average harvest of 9.0×10⁴ resting eggs per a gram (dry weight) N. oculata was achieved, which was 2.5 times more efficient than that from batch cultures. Although the water quality was comparatively improved (less concentrations of NH₄-N, NH₃-N and DON) in semicontinuous rotifer cultures, two out of four cultures collapsed on 15-20 th days, probably due to the bacterial effect. The semi-continuous cultures were stabilized by placement of a nylon filter to remove particulate organic materials. With a filter, 1.3 times more resting eggs were harvested on average.

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The stratified charge combustion system has been widely studied due to the significant potentials for low fuel consumption and low exhaust gas emissions. The mixture formation process for a direct-injection stratified charge engine is influenced by various parameters such as the atomization, the fuel evaporation, and the in-cylinder gas motion at high temperature and high pressure conditions. It is difficult to observe the in-cylinder phenomena in such conditions and also challenging to analyze the following stratified charge combustion. Therefore, the combustion phenomena in idealized stratified charge conditions aiming to analyze the fundamental stratified charge combustion are examined. That is, an experimental apparatus which can control the mixture distribution and the gas motion at ignition timing was developed, and the effects of turbulence intensity, mixture concentration distribution, and mixture composition on stratified charge combustion were examined. The schematic of experimental setup is shown in Fig. 1. Three volumes separated by two partitions were evacuated and then three premixtures were charged simultaneously through pressure regulators. After the charging was completed, the gas motion generator was operated to control turbulence at spark timing. After partitions were removed, ignition was made. As a result, it was found that in stratified charge combustion using propane-air mixture, when the overall equivalence ratio, φo, is unity, no advantages by charge stratification is found, but when φo is set at 0.8 combustion is enhanced by additive effects combining turbulence with charge stratification, and that combustion is enhanced by strong turbulence in slightly stratified charge fields using methane-air mixture, but extending stratification brings unfavorable results compared with the homogeneous condition.

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While global warming has become more deeply concerned, it is vital for Japan, which has world's top energy efficiency, to proactively adopt renewable energy in consumer category to shift from high dependency of fossil fuels. As for such approach, we have made comprehensive analysis and determination for usage of solar thermal energy. Although it is one of the most effective green technology to reduce GHG emission today, number of installation in Japan has been declining as well as its market shrinking causing withdrawal of manufacturer from the division. On the other hand, installation of such equipments in abroad has been growing which tightened competition resulting in improvements of cost performance and technology, and eventually price-reduction. Thus, we have completed verification test of foreign-made solar heat panels on behalf of Ministry of the Environment and examined its usage, economic impact and influence of installation in order to stimulate domestic market of solar heat panel.

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In this paper, it is purpose to study the effect of the size of tank and impeller to the liquid-liquid dispersion on mechanical agitation. Tank diameters used in this experiment are 150, 200 and 250 mm respectively. Then, every particle size is measured by a microscopic photograph method, and each mean surface-volume diameter is calculated and still more energy efficiency of agitation is required. So, the following results are obtained. (1) The values of agitation torque are almost same, though each size of tank diameter is different. (2) Relationship of specific interfacial area to agitation power is shown as next experimental equation. log S_A=0.399 log P+3.376 log S_B=0.386 log P+3.318 log S_C=0.385 log P+3.262 S : specific interfacial area (cm²/g), P : agitation power (watt) A : 150mm of tank diameter, B : 200mm of tank diameter C : 250mm of tank diameter (3) The specific interfacial area becomes smaller as the size of tank diameter is increasing. When tank diameter is 200mm, the value of S_B/S_A is 0.876 at 1 watt and 0.825 at 100 watt. In the same way, when tank diameter is 250mm, the value of S_C/S_A is 0.770 at 1 watt and 0.720 at 100 watt.

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This paper describes the Oil Shipment Scheduling Expert System (OSSES) to solve the oil shipment scheduling problems for berths and arms and the path selection problem. These problems have many complex constraints. Therefore, the expert system which can solve efficiently these problems is needed. OSSES can make one-day scheduling on shipping many petroleum products for many ships under the consideration of the deadlines and the line-blending and pipeline-cleaning mechanisms. OSSES can perform scheduling in response to some accident.

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Slurry erosion with sand particles is a serious problem for pumps operating at the Yellow River pumping station. Therefore, a technique to predict erosion volume loss is required for selecting erosion resistant material and determining specification of the maintenance period. This paper reports a method to predict the volume loss of SCS6 specimen using slurry jet apparatus. An equation for prediction is derived from combining an analysis of sand particle behavior in the slurry jet apparatus with measurement of surface profile on specimens obtained by slurry jet test by silica sand of approximate 60μm in mean diameter. There is a critical value for kinetic energy of particle above which erosion occurs being about 1.0x10^-6N•m for SCS6. It was found that the loss was a maximum at an impact angle of about 40 degrees. The equation can predict the wear depth on the slurry jet test with the Yellow River sand of approximate 30μm in mean diameter.

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 The building in our study features a green façade, a heat source system with renewable energy, natural ventilation, and a thermo-active building system (TABS). The floor plan of the building has an open hallway along the windows as a "perimeter aisle, ” and the combination of this open hallway and the green façade functions as a thermal buffer zone. Two air-conditioning systems are installed in this building— a ceiling radiation air-conditioning system, and a whole-floor blow-off air-conditioning system. The ceiling radiation air-conditioning system employs a reverse slab structure. In this system, ceiling radiation is performed by allowing cold or hot water to flow through a pipe buried in a ceiling slab. The ceiling radiation air-conditioning system employs a ceiling consisting of a concrete slab with a large thermal capacity; this raises the comfort and stability of the indoor thermal environment. This building also features TABS. Since the late 1990s, many buildings in Europe have installed TABS. However, only a few buildings in Japan have installed TABS. The authors surveyed the heat flux of the ceiling surface and indoor thermal environment of the building from 2017 through 2018. The ceiling utilizes the heat storage of concrete, and maintained a constant temperature in the workplace when the air conditioning system was switched off on a holiday. In that regard, making use of the thermal behavior of the skeleton improves the operation of the ceiling radiation air-conditioning system. The thermal environment of the perimeter is stabilized by the autonomous thermal behavior of the skeleton in an operating ceiling radiation air conditioning system. A time lag in the heat flux occurs because of the heat behavior of the skeleton in a building with TABS. The heat flow of the ceiling surface after office hours was reduced by advancing the operative schedule by two hours, and the ceiling radiation air conditioning system operated efficiently, thereby suppressing energy waste. In addition, it was confirmed that the coefficient of performance (COP) of the air-source heat pump (HP) increased with a peak shift of the heat source load, because of cool early morning outdoor air.

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