Tokyo Metro Co., Ltd. Operates nine subway lines with 195.1km of track and total of 179 stations in and around central Tokyo.The system carries 7.58 million passengers each day, and plays an important role as a vital link in Tokyo transportation network.
To ensure the unremitting pursuit of safety and the provision of high-quality, customer-oriented services, Tokyo Metro established Comprehensive Learning and Training Center in 2016. The Center includes a training line that simulates a real operational subway line, allowing staff to acquire complex and integrated knowledge and skills through realistic training without having to practice on a real line in the middle of the night after passenger services have finished. This report introduce about facilities of the Center and Tokyo Metro’s training program for subway operation and maintenance staff.

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　This paper considers a variable selection problem in linear regression analysis when multicollinear- ity exists between explanatory variables. To solve the problem, we review “predictive principal variable(PPV) selection criteria” proposed by Kuroki and Matsuura[1] he PPV selection criteria are formulated based on the fact that the covariance matrix of estimated regression coefficients comprises two parts: the residual sum of squares of a response variable for the given explanatory variables, and the design matrix of the explanatory variables. Given the PPV selection criteria, the variable selection procedure (PPV method) incorporates stopping rules without employing statistical hypothesis testing or subjective judgments. In addition, comparing the PPV method with existing variable selection criteria, the PPV method(i) enables selection of a subset of explanatory variables that take both prediction accuracy and degree of multicollinearity into account,and (ii) is useful for high-dimensional data analysis according to Pareto’s principle under the assumption that the sample size is smaller than the number of the whole explanatory variables but not than the number of important explanatory variables.

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　This report introduces the 4th research meeting for knowledge sharing of “Service Excellence Division” and “Production Innovation Division”.
　We focus on and discuss Blockchain.
―Using a peer-to-peer network
―About a trustless system
―What are Smart Contracts?

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　In the previous issue, I investigated the actual state of injustice at 2 automobile-related companies. In this paper, I investigated 4 material-related companies, and verified the actual state of injustice at 6 companies and the appropriateness of prevention by each company. Based on these facts, I want to offer to many other organizations self-check confirmation as a preventive action to eliminate these injustices as soon as possible. In addition, I hope that “The Japan Society for Quality Control” to promote further activities and contribute to the eradication of injustice too. By implementing these proposals, I hope that the eradication of injustice, the “basic value” of the first stage of the customer value four-stage theory, will be achieved as soon as possible. And I hope that it will be closer to the “fourth stage” that will impress customers in unexpected ways.

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　In some major companies in Japan, many inappropriate manners in quality management such as rewriting inspection data by using invalid data, using inspection data applied to former data, rewriting inspection conditions to satisfy requirements and producing and delivering products to have specification that is not satisfy customer requirements have been occurred recently. And those inappropriate manners deteriorated reliability and safety of those products, and the sales of those products fell down and also the presidents were forced to leave from their position in some cases. The research group for high reliability and safety of JSQC have been investigating and studying about those inappropriate manners in quality management. This report picked up four companies and investigated causes of inappropriate manners in those companies, and studied preventive methodology against predictable problems. Vol 1 of this report investigated causes of inappropriate manners in those four companies.

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　This article introduces JSQC-Std 22-001 “Guidelines for New Product and Service Development Management” developed by the Japanese Society for Quality Control（JSQC） in 2019. In order for an organization to continue to have its significance in the midst of a drastic change in the business environment, it is essential to continue to create new value for customers and society by grasping their needs and linking them to the seeds（technology, etc.） that the organization itself, its affiliated companies or partners have. New product and service development management is defined as a series of activities to determine the processes and/or systems for effectively and efficiently carrying out new products and services development, and to maintain, improve and innovate them for the next product and service development. For the purpose of contributing to the improvement of the quality of products and services, this standard provides fundamental concepts for new product and service development management, recommendations for major activities to be addressed, and explanations of methods that are useful in their practice as one compiled package.

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　The four experimental designs were investigated as typical examples of the non-orthogonal experimental designs. These four cases reduced the number of experiments than the applicable orthogonal design. The experimental efficiency of each design was only slightly smaller than the orthogonal design.
　Four cases, that is, the designs in which several experiments were omitted from the assumed orthogonal arrays intentionally, or in which several experiments were added or expanded were also investigated by numerical simulations. As results, it could be confirmed that there are no big problems with the powers of test of non-orthogonal experimental designs practically.
　As there are no serious bottlenecks in the practical applications of non-orthogonal experimental design adopted to engineering affairs, the profit by reducing the number of experiments is fairly large.
　When experimenters could not assign factors to the assumed orthogonal array because of lack of columns, they will adopt one more bigger orthogonal array. Minimization of the number of experiments will agree with the request of experimenters, and has much worth.
　Though the precision of estimates depends on adopted non-orthogonal experimental design, non-orthogonal design can make it equal to the corresponding orthogonal design about the specific important factor.

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