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This study examines the economic efficiency associated with firm location in a non-traded goods industry. This industry comprises of two segmented regions (markets) and a fixed number of potentiall...

In this article, we introduce the notion of “m-dimensional n-principal points,” which is a generalization of the notion of n-principal points. A set of m-dimensional n-principal points of a distribution is defined as a set of n points that optimally represents the distribution in terms of mean squared distance subject to the condition that the dimension of the linear subspace spanned by the n points is at most m. Its properties and connections to principal components are investigated for elliptically symmetric distributions and a location mixture of spherically symmetric distributions.

For each positive integer k, a set of k-principal points of a distribution is the set of k points that optimally represent the distribution in terms of mean squared distance. However, explicit form of k-principal points is often difficult to obtain. Hence a theorem established by Tarpey et al. (1995) has been influential in the literature, which states that when the distribution is elliptically symmetric, any set of k-principal points is in the linear subspace spanned by some principal eigenvectors of the covariance matrix. This theorem is called a “principal subspace theorem”. Recently, Yamamoto and Shinozaki (2000b) derived a principal subspace theorem for 2-principal points of a location mixture of spherically symmetric distributions. In their article, the ratio of mixture was set to be equal. This article derives a further result by considering a location mixture with unequal mixture ratio.

The purpose of this study was to use a newly developed computerised scorebook for tennis in order to clarify the characteristics of tennis tactics used on specific court surfaces. The authors developed a computerised scorebook for tennis that calculates the time duration of shots, points, and the time between points. Data were collected from matches played by male Japanese intercollegiate players. A total of 97 points were observed. Two observers (A, B) were recruited for recording matches using the scorebook. The mean error of observer A was 0.003±0.05 s, while the mean error of observer B was 0.02±0.10 s.The computerised scorebook for tennis was used to collect data for clarifying the characteristics of tennis tactics used on specific court surfaces. Forty-one matches from the Grand Slam tournaments held in 2003 and 2004 were analyzed. The scorebook recorded the final shot of each point, the result of each point, and the time duration of each shot. The final shots were categorised into the following 5 g...

The mechnisms of synthesis of mammalian selenocysteyl-tRNA were studied with murine active enzyme fractions. (75Se)Selenocysteyl-tRNA was synthesized in vitro by 500kDa protein from seryl-tRNA and (75Se)HSe-, which should be activated with ATP by 20kDa protein. This and other factors in mamalian systems are compared with those in Escherichia coli.

A biosensing system based on the response of fungal cells was used for the evaluation of antifungal activity of medicinal plants against Aspergillus niger. This system measured the hyphal growth rate in real time in the presence or absence of Chinese herbal extracts. The sensitivity of this system was 100-fold higher than that of conventional methods, and is advisable for the screening of antifungal compounds.