In this paper a test of the equality of several signal-to-noise ratios for p kinds of signal-response systems is considered. A simple linear regression model is assumed for each signal-response system, then the problem is equivalent to the test of the equality for two or several noncentrality parameters of noncentral t distributions. New simple testing procedures are derived based on the variance stabilizing transformation, and their sizes and powers are investigated. They are also compared with the tests proposed by Miwa. It is shown that the proposed simple procedures are conservative and that their sizes are close to the nominal level.

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Recent empirical evidence casts some doubts on whether efforts toward improving customer satisfaction are actually having any managerial effect such as increase of market share or loyalty. Supposed that this kind of doubt and evidences on negative correlation come from lack of consistent customer satisfaction data beyond re-purchasing cycle, this paper analyze longitudinal change pattern of customer satisfaction and its correlation with market share utilizing quality improvement expectation data. These data were obtained by the surveys conducted each three years over the past 25 years for the three matured products : refrigerator, TV and washing machine. As a result, it revealed first that customer satisfaction index is determined by the relative discrepancy between their perceived quality and expectation and that their expectation depends highly on the market business condition, that is, the index decreases as the business is booming while it increases as the future prospect is sluggish. Second it was found that customer satisfaction affects significantly positive impact or correlation to the market share delayed from 6 years to 9 years corresponding to the re-purchasing cycle of each product. These results are common to the three products. This implies that customer satisfaction should be still company object leading to the managerial effect and an effort to continue consistent customer satisfaction survey in term perspective is imperative.

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Recently, Organizational accidents have occurred frequently in medical industry. A great number of hospitals have introduced a human defense-in-depth by doctors and nurses. However, a defense-in-depth could be contribute to accidents because they make systems more complexity, and hence more opaque, to the people who manage and operate them. In this study, we examine the validity of human defense-in-depths with laboratory experiments. Our results from laboratory experiments show that double defenses are the most effective for preventing accidents if a defense-in-depth consists of homogeneous defenses. In addition, a defense-in-depth are effective for preventing accidents if a defense-in-depth consists of heterogeneous defenses.

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Mitsubishi Automotive Engineering Co., Ltd., Japan (MAE), received ISO9001-1994 Quality System certification in Feb. 1999, and ISO14001 Environment Management System certification in Feb. 2000 for all of 9 sites in Japan using a paperless (computer data originated) system, which was rare for an engineering company in Japan at that time. MAE was also certified for ISO9001-2000 version for all 9 sites in Japan in February 2002. Normally, it is thought that the amount of paperwork will increase when adopting ISO management system. However, in our case, we eliminated large amounts of paperwork by using a paperless system. In total, the result amounted to 1.6 million pages decrease in approximately 2 years for ISO 9001 and 14001 systems. This resulted in savings of 30 million yen per year, including labor costs for copying, sending and filing papers. For ISO 9001, we have developed and implemented a unique Process Management System (PMS), which preceded 3 years to the concept of the process oriented management system introduced in the year 2000 version of ISO 9001. Three kinds of survey for Customer Satisfaction were implemented to check how the customers were satisfied with our output. These activities for ISO helped a great deal to upgrade the quality level of the output and also the quality consciousness of the whole employee.

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