著者
大山 聖一
出版者
一般社団法人 日本エネルギー学会
雑誌
日本エネルギー学会誌 (ISSN:09168753)
巻号頁・発行日
vol.74, no.3, pp.137-146, 1995-03-20 (Released:2010-06-28)
参考文献数
55
被引用文献数
5 6

The recent status of catalytic hydrogenation of carbon dioxide to methanol was investigated. Although catalytic hydrogenation of CO2 requires H2 and energy, it shows much higher reaction rate than other CO2 conversion technologies. Especially, conversion to methanol is a promising technology because of its excellent characteristics as a fuel. Thermodynamically, lower temperatures and lower pressures are favorable for methanol synthesis from CO2 and higher temperatures are favorable for the reverse water gas shift reaction. Thus, a catalyst which is highly active below 473 K promises low-energy conversion to methanol. CO2 hydrogenation technology is classi-fied into a gas-phase synthesis and a liquid-phase synthesis from its reaction method. In the gas-phase synthesis, Cu/ZnO-based catalysts show space time yields comparable to those in the conventional methanol production process from syngas. The liquid-phase synthesis employing a homogeneous catalyst is expected to operate at lower temperatures than the gas-phase synthesis. In order to achieve efficient CO2 conversion to methanol, it is necessary to develop an active catalyst system at lower temperatures.
著者
小平 剛央 釼持 寛正 大山 聖 立川 智章
出版者
進化計算学会
雑誌
進化計算学会論文誌 (ISSN:21857385)
巻号頁・発行日
vol.8, no.1, pp.11-21, 2017 (Released:2017-08-04)
参考文献数
27
被引用文献数
1

We propose two optimization benchmark problems with actual engineering design features of car-body structural development using response surface method. The first is a single-objective optimization problem of weight minimization. The second is the multi-objective optimization problem of weight minimization and number of common thickness parts maximization. These benchmark problems have key feature of real-world design problem, i.e. many variables and many constraint conditions. Furthermore, it is a discrete variable optimization problem. We present optimization results using multi-island genetic algorithm (single-objective optimization) and NSGA-II (multiobjective optimization). We also present optimization result of the benchmark problem where the discrete variables are treated as real variables. The benchmark problem is available on http://ladse.eng.isas.jaxa.jp/benchmark.
著者
大山 聖
出版者
進化計算学会
雑誌
進化計算学会論文誌 (ISSN:21857385)
巻号頁・発行日
vol.9, no.2, pp.86-92, 2018 (Released:2018-10-10)
参考文献数
24

Evolutionary computation competition 2017 was held in December 9, 2017 in conjunction with evolutionary computation symposium 2017. It was confirmed that evolutionary algorithms can discover good designs of the design optimization problem of vehicle structures provided by Mazda motor company. Nine teams participated in the single-objective optimization division and eleven teams in the multiobjective optimization division. Prof. Shinya Watanabe's team from Muroran Institute of Technology won in the single-objective optimization division, Prof. Isao Ono's team from Tokyo Institute of Technology won in the multi-objective optimization division. The industrial use special prize was awarded to Dr. Tomohiro Harada's team from Ritsumeikan University. In the single-objective design optimization division, the groups using evolution strategies found good Pareto-optimal solutions. In the multiobjective optimization division, the groups who found good Pareto-optimal designs studied characteristics of the benchmark problem very much and implemented the most suitable optimization algorithm. Mazda benchmark problem has many severe constraints and thus feasible design space is strictly limited. Some teams used special techniques such as ε constraint method. Current result indicated that balance between search in feasible region and infeasible region may be important for constrained design optimization problems.