Numerical methods based on the finite difference method with general curvilinear coordinate system are frequently used for investigation of flow fields inside domains with complex geometry. One of the most tiresome and time-consuming work for these methods is the grid generation. In the first report (1998), we constructed the grid system by adopting the multi-block grid generating method. It took about a week to finilize the work, but the grid quality was still unsatisfactory. In this paper, a new grid generation technique based on "spring model" and a computer program which utilizes the GUI (graphical user interface) of PC are described. The grid system of the Ise Bay was reconstructed by using this program. The geometrical accuracy of the grid system was fairly enhanced as well as the reduction of construction time. Features of the computer program named "Rubbnet" and its usage are introduced in detail.

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This paper describes the method of determining the velocity vector for a flow field using optical flow. It is valuable to estimate quantitative velocity automatically from video sequences since visual tracking by human is tedious work. Digital video has been taken for an experiment which mixes the different density of fluid in a test tank. The 12 successive frames at intervals of 0.5 seconds were selected for velocity estimation of the fluid. Every frame was re-sampled to adjust the coordinate, and then the optical flow method was applied. The results of estimated velocity are considered to be reasonable to be reasonable by visual judgment.

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The flow behaviour around a square cylinder is characterized by the unsteady 3-D structures induced by the Karman vortex and the horseshoe vortex formations. The plane 2-D and the 3-D numerical models are applied to the computations of those flows in both the closed and open water channels. In the plane 2-D calculation, the depth-averaged shallow water flow equations, which have been used for various problems in river engineering works, are applied to the flow in open channels. For the sake of simplicity, the eddy viscosity coefficient is evaluated by the simplified 0-equational formulation. The non-linear k-ε model which includes the effect of the strain parameter is used in the 3-D computations of the flows in closed and open channels. Applicability of the turbulence model to the Karman vortex shedding in the 2-D flow field is firstly investigated through the comparison of the calculated results with the experimental ones conducted in the closed water section by Lyn and the model constants are adjusted. Then, the 3-D computations of unsteady flows in open channels are carried out focusing on the Karman vortex and the horseshoe vortex generated around the cylinder. Effects of the depth to the 3-D flow structures in open channels are also discussed through the comparison of the numerical results under different conditions of water depth.

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In the air pollution concentration computation model with the general curvilinear coordinate system used untilnow, when there is a protrusion on the ground such as a hill zone and a mountain range, it is possible to compute along the topography of the ground. In such a case, it is very effective, on the other hand, the basic formulas are inconvenient to become complicated to treat simply. In the case of the flat topography, it will be enough in analysis which used an atmospheric pollution concentration computation model by the 3-dimensional Cartesian coordinates. Therefore, we developed a simplified computer program which solves a wind velocity phase and a diffusion phase alternately in the time marching formula in the 3-dimensional Cartesian coordinates. It is assumed that sulphur dioxide discharge from the smoke source of the generation plant of electricity which is located in Tianjin city in China diffuses to the air. We calculated the downstream flow of pollutants carried by the wind by plugging sulphur dioxide discharge data for each second.

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"Nuclear fusion is connected with the following subjects of scientific and technical fields. They are (1) Energy production in stars, (2) Thermonuclear weapon (hydrogen bomb), (3) controlled nuclear fusion (fusion reactor) First, I will briefly explain how enormous amounts of energy are continuously produced in stars. Secondly, the current status of "controlled nuclear fusion" will be examined from the viewpoint of a radiochemist. Contrary to the general knowledge or belief, highly radioactive atoms are produced in the surrounding materials. In a "fusion reactor", the atoms are produced by the interaction of high energy neutrons with elements like iron and nickel. In the case of trouble or accident, it is quite difficult to access the reactor. Finally, problems concerned with the making of hydrogen bomb and its testing are outlined in the Appendix.

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The Habu dam is a reservoir for irrigation on the Tomoe river, a tributary of the Yahagi river. This field survey was conducted between May 13 and November 18,in 1981. To assess the river water quality, water samples and plankton were collected almost every day during this study period. The results of this study showed that seasonal changes in quality assessed in terms of paramenters such as COD, T-N, and T-P distinguished five distinctive periods. In this lake, organisms of two species of algae. Asterionella and Fragilaia, increased in number greatly in spring and much less in autumn. The seasonal changes in type and quantity of phytoplankton in this lake depended closely on temperature of the water and concentration of phosphorus. The T-N and T-P concentrations ranged between 14-110 μg at/1 and between 0.2-3.1 μg at/1,indicating that this lake is Mesotrophic type.

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The purpose of this paper is to study "unlawful acts on Collaboration" of enterprises. It proved that the environmental pollution lawsuit in Yokkaichi was very useful. Because today's decision is in no way attributable to any desire to dilute "Civil Law Article 719" in order more easily to apply it to State, but follows solely as a necessary consequence of our duty to re-examine, prior decisions to reach the correct constitutional meaning in each case.

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We performed this study to determine the effect of the late asthmatic response, using guinea pigs exposed to NO_2 gas (0.5ppm) 6 times per week for 13 consecutive days. After completing of the fourth inhalation experiment, when sensitization via the respiratory tract by albumin of different species was established, the presence of the delayed dyspneic reaction was examined for 11 hours by the body plethysmographic method. By numerical study of various indices on the breathing curve, changes in fine respiratory symptoms were detected. Delayed tachypnea, extension of exhalation and decreased respiratory amplitude were noted as the result of NO_2 loading. An increase in the degree of dyspnea was also recognized in the evaluation by the values on the breathing curve pattern.

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The chinese character Huanjing [環境, environment] appeared first in the chronicle of the Yuan Era. This chronicle was written by OU-YANG Xiu in 1060. Huan jing means round or a zone being surrounded. It later took on the meaning of environment and surroundings or circumstance between 1936 and 1943 in Japan. The word Hyan jing [environment] was possibly reintroduced to China before 1944 with additional meaning from the Japanese word Kankyoh Some Japanese scholars today believe that the word environment is a field or place (a habitat), and media where a man lives. Internationally, scholars generally believe the environment is the object against the subject. I think that the subject is the individual against the whole. The environment is a set that consists of all the individual elements, namely the environment is the totality of the individual elements. So it is better that the subject is called the environmental subject, and the individual elements are calling the environmental elements The earth or the word consists of all kinds of sets, for example : a country, a family and a school are seen to be a set. Based on the sets, the environment appeares through the following four steps. 1) A set is derived from a basa ; 2) An individual element is decided to be a subject ; 3) Some elements relating to the subject are recognized to be environmental elements ; 4) A totality of the individual elements consists, and environment appears. The Subject and object are on equality at the first step. and place of Subject is able to be reversed with the place of object, but nature has been the object for man since the 18th century, nature is the environment of man, so some environmental problems have appeared here and there. It is necessary that the relationship between nature and man returns to the first step to solve these environmental problems.

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The purpose of this paper is to consider the essence of mathematics of Takebe Katahiro (1664-1739) by investigating his method of finding the maximum in Tetsujutsu Sankei (1722). It has been said that he had first done a calculation of a derivation for finding the maximum in chapter 6 of the treatise, but that is not strictly true. A close look at the chapter will reveal that his method has nothing to do with the theory of differential.

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This paper reports the results of a questionnaire study completed in July, 1998 by 120 Yokkaichi University first year students of English. The purpose of the study was to get a better understanding of the types of English related experiences students have had prior to entering the university. The study also attempted to determine the extent to which the reform measures implemented by the Japanese Ministry of Education in 1994 have been successful in helping students develop communicative ability and intercultural understanding. The results indicate that the Ministry of Education's reform measures have been only somewhat successful. 83.2% of students reported having had at least one "Oral Communication" class during their high school years. However, in general, students were not particularly satisfied with the extent to which their English classes helped them develop communicative ability and intercultural understanding. Students instead reported that their English education mainly focused on the study of grammar and reading/translation, via traditional teaching methodology, i. e. "yakudoku" instruction, used to help students prepare for university entrance exams.

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In the last years of the 1980s, a new trend known as Magical Realism. emerged in Nigerian literature. I think that Ben Okri's "Worlds That Flourish" is one of the most typical examples written with Magical Realism. African people could become familiar with the novel of this new trend, because they could casily find their own mythological world that is deeply rooted in their souls. Through this Japanese translation, I would like to clarify that Social Realism, through which social comment can be caused, deepened into Magical Realism and through this, 'genuine' African literature was born.

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The purpose of this investigation was to determine the listening ability of students who took English Communication-Basic (hereinafter referred to as ECB) in 1998 by checking their evaluation of listening materials, and to reconfirm the level (already established in 1997) of listening materials which were most suitable for use in ECB classes and their self-study hours at home. The investigation was made in April, 1998,with 102 students who took the course. The results of the investigation revealed that 88% (as compared to 93% in 1997) of the students perceived the radio program 'Eikaiwa Nyumon' broadcasted by NHK in April, 1997,favorably for self-study use, and 70% (as compared to 80% in 1997) of them had the impression that the TV program 'Eikaiwa' broadcasted by NHK in the same month was most suitable for use in ECB classes.

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