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We are working to develop a support system for process planning in machining. In the 1st part of this investigation, to improve the system’s applicability to products with a large number of holes, a greedy algorithm was used to search among solutions. Through comparison of the machining time obtained by the system with that obtained by operator design, it was confirmed that the configuration of the system is valid. To take the system’s two objective functions into account simultaneously, namely, minimization of machining time and minimization of electric energy consumption, here we propose a method to convert them into costs. The results show that process planning that prioritizes machining time instead of electric energy consumption is realistic, and that the percentages of the costs for machining time and electric energy consumption included in the machining cost vary depending on the shape of the workpiece.

In order to improve the applicability to products having a large number of holes, the greedy algorithm is used in the process of searching for the solution. The constitution of the system was confirmed to be valid from a comparison between the machining time obtained by a proposed system and operator design. Then, the cutting force in milling and drilling processes performed on a workpiece having a large number of holes and steps is calculated through application of cutting models proposed by Usui et al., and the machining power and electric energy are estimated on the basis of the calculated cutting force. To enable process planning in which two objective functions such as machining time and electric energy are taken into consideration, it is proposed that convert those quantities to cost.

Recently, biodiesel has attracted attention as a possible petroleum substitute. Biodiesel is an alternate diesel fuel formed from triacylglycerols, which are the principal ingredient of oils and fats. However, in Japan, there is not enough land space to cultivate the raw materials for such oils and fats, and most imported oils and fats are used for food purposes, such as cooking oil. Furthermore, most of the waste cooking oils includes animal fats which contain long-chain saturated compounds and free fatty acids. The former has a high freezing point and the latter forms a soap with the alkali catalyst used in biodiesel production, reducing the yield. The biodiesel production from the waste cooking oil was examined. As a result, it was clarified that ion-exchange resin two step method is suitable for waste oil with little animal fats, and the pyrolysis method is suitable for waste oil with much animal fats.

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.

This work focused on the Cu-based spinel type oxide catalysts for the steam reforming of dimethyl ether (DME SR) reactions. Among Cu-based spinel-oxides, CuFe_2O_4 spinel and γ-Al_2O_3 composite catalyst exhibited the highest activity for DME SR. Reduction behavior, crystal property, and Cu oxidation state of spinel catalysts were strongly affected by B metal elements. The heat treatment temperature range of 700-800℃ is most effective to enhance the catalytic performance due to the new phase of Cu-Fe-AlO_4 formation by solid-state reaction at the interface between CuFe_2O_4 and γ-Al_2O_3. No degradation could be observed for the catalyst subjected to the cooling-heating process in O_2 atmosphere which is assumed the daily start-up and shut-down (DSS) operation. The degraded catalyst after the DSS operation in steam could be recovered by the heat treatment in air at 375℃, because the active sites of γ-Al_2O_3 were regenerated and the coke deposits were removed.

本稿は歴史的町並み景観が保存され日帰り観光地として認識される埼玉県の川越を事例に，都市が姿や機能を変化させながら持続する要因を住民の価値観に求めて検証するものである．川越観光の中心地である一番街は近世城下町の町人地として成立し，商業地として繁栄した後，商業機能が衰退する段階を経て再び観光地として活性化した．この段階的な変化の過程において地域住民の行動を分析すると，商業地域として繁栄していた段階における地域住民の行動は自らが経営する事業の利益を主眼としたものであったが，商業機能の衰退によって地域全体の商業活性化をめざした行動へと変化していた．この行動変化の基底には，地域住民に共有された危機感が存在していた．地域住民の危機意識は当初商店主らに経営に関わる危機感として意識されたが，徐々に一般の住民にも地域の存続に関わるものとして共有されていった．本研究から地域住民の危機意識が都市の機能や姿を変える一例が明らかになった．