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The aim of this feasibility study is the practical implementation of a small output Organic Rankine Cycle (ORC) less than 20kW. In this study, the evaluation method of a turbine efficiency which is the major component of the ORC was examined, moreover, the performance of the ORC was evaluated based on the turbine efficiency using the heat source of Obama hot spring in Unzen-City. The outlet temperature of the turbine applied the insulation treatment was almost same the temperature without the treatment. This result indicated the influence of the heat absorption on the turbine of the ambient temperature for the working fluid was small. The adiabatic efficiency in the turbine test itself was about 7.9%. It indicated the working fluid absorbed the mechanical frictional heat generated inside the turbine. In the verification test of Obama hot spring, the thermal efficiency of the prototype ORC was 2.4%. The turbine efficiency at the operating point in the urbine test was 21.2%, whereas the turbine efficiency in the ORC verification test was 19.2%.

It has been increasingly important to project the future risk of small-scale torrential rainfall in summer, called ‘Guerrilla-heavy rainfall' in urban areas in Japan. In this study, we implemented some analysis in August in Kinki Region, from the view point of both the rainfall distribution and the unstable atmospheric condition. First, we picked up Guerrilla-heavy rainfall events with both tracking algorism and visual judgement of rainfall distribution of NHRCM05 output. Then, we analyzed the atmospheric stability of the events that was picked up, using a parameter SSI (Showalter Stability Index). As a result of T-test, it is implied that the number of days having Guerrilla-heavy rainfall will significantly increase at the end of August, and that this tendency corresponded to the more unstable SSI in the future. In conclusion, the season when Guerrilla-heavy rainfall is likely to occur will be longer in the future summer, with the more unstable SSI at the end of August

Changes in mass with time due to gas evolution during carbonization were observed for particles and a cylindrical pellet of various coals heated respectively in a thermogravimetric balance and a microautoclave. The experiments were carried out for a range of the heating rate from 1 to 50K/min, the holding temperature from 673 to 823K and the nitrogen gas pressure of 0.1 and 1.0MPa. Effects of these operating variables on the gas evolution characteristics were experimentally examined. It was demonstrated that the gas evolution characteristics depend on the heating rate and the holding temperature as well as coal nature. Moreover, the total amount of gas evolved at a holding temperature was shown to be independent of the heating rate and to increase with the holding temperature. A simple reaction model is proposed for gas evolution which assumes coal to consist of two components having different reactivities for pyrolysis; one producing gas along with formation of semicoke via plastic intermediate and the other converting directly to gas. The model parameters were analyzed by fitting the model to the observed results and successfully utilized to explain observed results at different operating conditions.

千葉工業大学 ; 平成27年度

博士（工学） ; 日本大学

京都議定書の第1約束期間を目前に控え、地方自治体においても地球温暖化対策の策定・実施が求められている。本研究は通常用いられる領域原則にもとづく二酸化炭素排出量をもとに各都市が削減目標を設定することが適切であるかどうかを検討するために、産業連関分析によりサービス都市 (福岡市) と工業都市 (北九州市) のエネルギー消費、二酸化炭素排出構造について比較分析した。その結果、1人当たり二酸化炭素排出量について、都市域内から直接排出される二酸化炭素のみを対象とする場合と、都市の移輸入・移輸出を通じた外部との間接的な二酸化炭素排出量のやり取りを考慮した責任排出量では、大きく結果が異なることが示された。 On the verge of the first commitment period of the Kyoto Protocol, effective strategies and local measures for climate change mitigation and its implementation is required for local governments in Japan. In order to evaluate applicability and validity of territory principle of IPCC for GHGs emission inventory at local level, this study describes the urban metabolic structure of energy and carbon in a Japanese service city (Fukuoka) and industrial city (Kitakyushu) by using Input-Output analysis technique. Per capita direct CO2 emission in Kitakyushu City is much higher than in Fukuoka City. However, the per capita responsible CO2 emission which is defined as direct and indirect CO2 emission minus embodied CO2 emission in export goods shows opposite results. This implies that the application of the territorial principle of IPCC inventory to a city might not be relevant to guide better directions of urban climate change policies. 本研究は平成16年度地球環境推進費「物質フローモデルに基づく持続可能な生産・消費の達成度評価手法に関する研究（代表：森口祐一）」の一環として行われたものである。

We predict the saturation phase of building-integrated photovoltaics (PV) for which complexsystem model coupled with electric power flow analysis are carried out. The detailed power flow analysis determines the probability of reverse current occurrence due to the additional PV installation in a twodimensional 6.6 kV-scale distribution network consisting 2500 grid-connected individual customers. The agent-based simulation including the customer agent and government agent describes the time-dependent behavior of the PV penetration in an artificial society. Growth of the building-integrated PV is assisted by a battery installation as a reservoir for the reverse current. However the excessive promotion for the PV penetration by the government results in increase in the cost of reverse current care.

With the growing importance of taking stepwise adaptation measures to climate change, we conducted a future change analysis of rainfall during the baiu rainy season using 150-year continuous run. We analyzed two aspects about the baiu rainfall: baiu frontal zones based on average daily rainfall in July and baiu extreme rainfall based on hourly rainfall. The results show that the rainfall area gradually moves northward in both the frontal zone and location of the extreme rainfall events. The analysis of future changes in average daily rainfall by region showed that there was a marked tendency for rainfall to in-crease in northern Japan, but there were also regions that contained periods when rainfall was lower than the historical average. The reasons for this are discussed in terms of the influence of sea surface temperatures and typhoons. Furthermore, we showed that the duration of extreme rainfall events will gradually increase in the future.

The statistical property of wind power fluctuation, which does not fit to the normal distribution because of its high probability of the extremal outlier, is regarded as a source of severe damage to power systems. In view of this, the authors have proposed an evaluation method for the impact of wind power fluctuation on power system quality, assuming that this heavy-tailed uncertainty obeys a power-law. In this paper, we first examine the validity of this assumption based on real data of frequency deviation under wind power interconnection. Then, the evaluation method is improved by extending theoretical results, and is applied to analysis of load frequency control model to verify its advantage over Monte Carlo methods.