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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

千葉工業大学 ; 平成27年度

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.

The efforts on material recycling conducted by Oki-town, Fukuoka-prefecture, have been reported through many preceding studies for its framework and results. The efforts of Oki-town have been extended beyond just “waste reduction programs”, to the town development project based around material recycling. The perspective of their efforts has not been summarized because of its diverse project contents. Thus, we made anattempt to summarize the whole image of the recycling project conducted by Oki-town.

Pseudo global warming experiments (PGW) were conducted with 1000m and 500m horizontal resolution for the 2012 Kameoka extreme rainfall event, which was the type of back-building convection system. As a result, the back-building system was very well represented in both of present and PGW experiments, and the rainfall intensity and total rainfall increased in PGW experiments. This is due to the fact that: in the future, the amount of condensation in cumulonimbus will increase and a convective unstable field will be realized (meso γ ~ β), the back-building structure will be strengthened (meso β), and the convective unstable atmosphere was continuously supplied from the south (meso α). We also showed that the result of 500m resolution can represent the back-building system much better than that of 1000m because 1000m resolution can capture future changes in meso-α, but cannot capture changes smaller than meso-β sufficiently.

和文：2000年代に入ってから欧州を中心に再生可能エネルギーの急成長が始まった。特に欧州各国では、化石燃料の削減のみならず原子力発電への限界も見据えて、100％再生可能エネルギーに向けた歩みをすでに始めている。2011年の福島第一原発事故をきっかけに日本においても再生可能エネルギーへの転換が急速にすすみつつある。そこで本論文では、再生可能エネルギーの普及政策の中で特に固定価格買取制度（以下、FIT 制度）等の果たしてきた役割とその評価について、海外と国内を比較しつつ、国内での現状と今後の見通しを論じる。その上で、地域における 100％再生可能エネルギーへの展望として、最終的に将来目指すべき100％再生可能エネルギー地域への取組みと可能性を論じる。長期的な100％再生可能エネルギーの実現向けては、中長期的な導入目標の設定が重要だが、再生可能エネルギーに占める割合や温室効果ガス削減目標など、欧州各国では2020年までに30％を超える野心的な目標を掲げる国が多数ある。さらにドイツを中心に 100％自然エネルギー地域の実現のため取り組みが行われている。その際には、電気だけではなく、熱利用や輸送燃料についてもエネルギー効率化と再生可能エネルギーへの転換が重要である。一方、日本では2012年からのFIT制度の導入により太陽光発電を中心に急成長を始めたが、100％再生可能エネルギーに向けた動きとして福島県のビジョンやエネルギー永続地帯での評価などがある。 ; 英文：Rapid growth of renewable energy in Europe and from the 2000s began. Especially in European countries, the limit of nuclear power generation is not the reduction of fossil fuel only be anticipation, have already started to walk towards 100% renewable energy. In Japan in the wake of the severe accident of Fukushima Daiichi Nuclear Plant of 2011 is progressing rapidly conversion to renewable energy. In this paper, especially feed-in tariffs (FIT) in the dissemination policy of renewable energy and the role that has played such as for the evaluation, while comparing the overseas and domestic, and the future status quo in Japan We discuss the outlook. On top of that, as the outlook to 100% renewable energy in the region, to discuss the efforts and possibilities to 100% renewable energy region and should aim ultimately future. Toward the realization of long-term 100% renewable energy, medium- and long-term introduction goal setting but important, such as the percentage and greenhouse gas reduction targets as a percentage of renewable energy, in the European countries 30% in 2020 country listed an ambitious goal that exceeds a certain number. In addition it has been made efforts for the realization of 100% renewable energy region around Germany. In doing so, not only electricity, is also important conversion to energy efficiency and renewable energy for heat utilization and transportation fuel. ...

In this thesis, we consider dimensionality reduction of parameters in a piecewise linear model of boost converter with PV input. The circuit is subject to a bi-objective optimization problem where the first and second objectives evaluate efficiency of input power and stability of periodic orbits, respectively. A trade off exists between the two objectives and is represented by a Pareto front. An approximation of the Pareto front is a criterion for the dimensionality reduction. Performing precise numerical experiment, a simple dimensionality reduction from two-dimensional parameter space into a one-dimensional parameter subspace is achieved.