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This study aims to focus on asset management of large‐scale information systems supporting infrastructures and especially seeks to address a methodology of their statistical deterioration prediction based on their historical inspection data. Information systems are composed of many devices. Deterioration process i.e. wear‐out failure generation process of those devices is formulated by a Weibull hazard model. Furthermore, in order to consider the heterogeneity of the hazard rate of each device, the random proportional Weibull hazard model, which expresses the heterogeneity of the hazard rate as random variables, is to be proposed.

Large‐scale information systems comprise many components, and different types of components might have different hazard rates. Therefore, when analyzing faults of information systems that comprise various types of devices and components, it is important to consider the heterogeneity of the hazard rates that exist between the different types of components. In this study, with this in consideration, the random proportional Weibull hazard model, whose heterogeneity of hazard rates is subject to a gamma distribution, is formulated and a methodology is proposed which estimates the failure rate of various components comprising an information system.

Through a case study using a traffic control system for expressways, the validity of the proposed model is empirically verified. Concretely, as for HDD, the service life at which the survival probability is 50 percent is estimated as 158 months. However, even for the same HDD, use environment differs according to usage. Actually, among the three different usages (PC, server, others), failures happen earliest in the case of PCs, which have the highest heterogeneity parameter and a survival probability of 50 percent after 135 months of usage. On the other hand, as for others, its survival probability is 50 percent at 303 months.

To operationally express the heterogeneity of failure rates, the Weibull hazard model is employed as a base, and a random proportional Weibull hazard model expressing the proportional heterogeneity of hazard rates with a standard gamma distribution is formulated. By estimating the parameter of the standard proportional Weibull hazard function and the parameter of the probability distribution that expresses the heterogeneity of the proportionality constant between the types, the random proportional Weibull hazard model can easily express the heterogeneity of the hazard rates between types and components.

This paper aims to make a comprehensive evaluation of the progress and achievements made by China and Japan in literature collection, publication and academic research of South Manchuria Railways Co (SMR) after the Second World War and points out the existing and urgent problems.

This paper adopts the methods of literature research, questionnaire survey, comparative analysis and expert consultation.

After the Second World War, both China and Japan made great achievements in the collection, publication and research of SMR data, as well as in the academic research of SMR. However, as a new research field, there are still some problems in deepening the excavation and utilization of SMR data, expanding the research fields, improving the research methods, etc.

SMR itself was the product of a war of aggression. Although it died with the defeat of the war of aggression, remaining SMR data also has very precious value, it records the history of Japanese aggression against China, is the biggest database for the study of the problems in China and northeast Aisa at that time. In addition to Japan and China, the USA and the Soviet Union also kept part of the SMR data, so that to involve them in the research of SMR is also the purpose of this paper.

Samezō Kuruma's career as a Marxist economist spans a period of roughly six decades, stretching from the beginning of the 1920s, when Marxism was quickly taking root in Japan, up to the early 1980s, when the nearly hegemonic influence Marxist scholars had enjoyed in the postwar period was on the wane.¹ Kuruma was born in 1893 in Okayama prefecture, west of Osaka. As the eldest son of a prosperous paper merchant, Kuruma was expected to take over the business one day, which did not interest him. Although not eager to become a capitalist, the study of capitalism attracted Kuruma early on, spurred by reading The Wealth of Nations at the age of seventeen. In 1914, Kuruma entered prestigious Tokyo Imperial University (now Tokyo University), where he had intended to study economics but switched to political science after finding the economics courses uninteresting.² Graduating in the spring of 1918, he found a job working for Sumitomo Bank in Osaka. Kuruma had been assured that the job would afford him an opportunity to pursue economic research, perhaps related to China, but his duties turned out to be far more mundane. He soon realized that he was not at all suited to a career in banking.