著者

川嶋 辰彦 野呂 純一

雑誌

學習院大學經濟論集 (ISSN:00163953)

巻号頁・発行日

vol.49, no.3, pp.161-186, 2012-10-01

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With understanding that the study of the external agglomeration economies is increasingly significant in both theoretical and applied analyses in the field of spatial economics,this paper attempts to investigate the influence of the T-external economies (i.e.,the external agglomeration economies stemming from "the total number of consumers who actually purchase a specific type of service") upon the utility level of those who consume the service.Our analysis is besed on the assumption that there exists a market where one kind of composite goods and one kind of service are transacted,and that an individual consumer in this merket may,if s/he can afford to do so,purchase any non-negative amount of the composite goods and either zero or one unit of the service.In this setting,we first obtain the demand surface by use of the following curves and surface as the basis: (i) a utility curve for the consumption of the non-negative amount of the composite goods,(ii) a utility surface for the simultaneous consumption of the non-negative composite goods and one unit of the service,and (iii) the income-density distribution curve.We also assume that the utility surface reflects the existence of external agglomeration economies stemming from "the total number of consumers who actually purchase the service" (i.e.,the equilibrium demand level for the service).The shape of the obtained demand surface resembles a platypus' upper bill with its right-hand side vertically trimmed to a degree.Secondly,from the demand surface,we obtain the derived demand curve which serves as the actual market demend curve.This curve has upward convexity and forms a bell-shaped curve.Thirdly,we briefly discuss the research agenda to follow the investigation in this paper.

著者

犬飼 道彦 西田 正 野呂 純 松田 明洋

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.123, no.9, pp.1040-1046, 2003 (Released:2004-05-28)

参考文献数

3

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This paper describes the advance of the ground relay of the line protection.First of all, we examined the ground fault in a resistively grounded power system. The protective relay detects the ground fault by the zero phase current in the system. There are two methods for the current input to the relay. One uses the residual circuit of CT secondary winding, and the other uses the CT tertiary winding. When the ground current is insufficient in the residual circuit, the CT tertiary winding is used. In order to omit the CT tertiary winding and to get more reliability, we reviewed the full-scale of relay and evaluating the error of CT. As result, almost all transmission lines could omit the CT tertiary winding.Next, we examined the ground fault with high fault resistance in a solidly grounded power system. When that fault occurs in the system, the PCM current differential relay acts by fault current. So, this relay possibly mal-operates when the CT secondary circuit is disconnected. Therefore, it uses a special CT to raise the reliability. Nowadays GIS has become small and the CT installation space has been decreased, it is needed to reduce these CT cores. In order to omit the special CT, we utilized the combination of the power relay and the rate of change of relay current. As a result, there is a prospect that the relay would not need the special CT.These improvements are effective to reduce cost too.