Diatom assemblages in the sediment and plankton collected from LaKe kanekin-to, Hokkaido, in September, 2002 was studied. 107 taxa of zooplankton and 272 taxa of phytoplankton were found in this lake, the dominant and subdominant species being Fragilaria crotonensis, Aulacoseira ambigua, and Tabellariafenestrata. Pediastrum argentiniense (Chrophyceae) is recorded in Japan for the second time.

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3D turbulent flow structures around a wing-body junction are characterized by the formation of a horseshoe vortex. The applicability of a non-linear k-ε model with the realizability conditions is investigated in this paper. The 2nd-order non-linear k-ε model tuned by Kimura and Hosoda (2000) is employed in the computations. The numerical results are examined through the comparison with the results in the laboratory tests conducted by Devenport et al (1990) using modified NACA0020 type wing section with 305mm chord length and 71.7mm maximum thickness. It is pointed out that the present model can simulate the fundamental aspects of the 3D flows around the wing -body junction.

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In order to clarify the effect of the embankment of Ariake reclamation project to the water quality of Ariake sea, tidal flow was computed by the two-dimensional numerical simulation and flow characteristics around the bay head were investigated. The discharging rate and the residence time of sea water of the bay head were determined, utilizing tracer particles and a passive scalar function. It was found that the discharge of sea water from the bay head consists of two phases. The discharging rate in the first phase increases faster than that in the second phase and its magnitude changes in the effect of the embankment as well as the tidal amplitude. On the other hand, the discharging rate in the second phase is almost independent on such parameters. The cause of the differences between the two phases was investigated through the study of the flow structures. At the boundary region between the bay head and the center, there exists a circular residual flow. The sea water of the bay head is transported by the flow to the bay center, immediately after the initiation of computation. Then, the discharging rate exhibits the rapid increase. The variation of the discharging rate by the embankment is probably due to slight change of the location of the circular residual flow. It is the reason why the discharging rate in the first phase shows above mentioned characteristics. Consequently, it was concluded that the discharging rate in the first phase do not represent the real tidal exchange. During the first phase, the area of the circular residual flow is filled with sea water of the bay head, and in the second phase, the discharging rate begins to show the net value of the tidal exchange. Then, residence times were computed from the latter discharging rates, and the values were from 50 to 279 days. The differences depend mainly on the magnitude of the horizontal diffusivity applied in each computation. The contributions of the advection and the horizontal diffusion to the discharging rate are almost same, when the horizontal diffusion constant is set as K=1.0m^2/s. As the horizontal diffusion constants increases, the contribution of the advection relatively decreases. Unlike the expectation, it was not found the trend to prolong the residence time by the effect of the embankment.

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In this paper, we introduce Streaming technology and SMIL(Synchronized Multimedia Integration Language). Streaming is the key technology when we intend to broadcast our presentation over Internet, and SMIL defines the integration of various multimedia materials for the presentation purpose. We also introduce the examples of these technologies using our seminar's lecture.

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The Area Demarcation System, which was introduced in 1968 by the Town Planning Act as a measure to cope with severe urban sprawl, is the system to divide the Town Planning Area into Urbanization Promotion Area (UPA) where urbanization would be promoted under the appropriate planning control and the Urbanization Control Area (UCA) where urbanization should be restricted as a rule. But two problems rose in the system in the process of enforcement; one was that too much farmland and forests had been enclosed in UPAs and another was the many loopholes in the land use control of the UCA. One of the cause of the second problem was the system "KIZON TAKUTl" ,which was introduced by the Town Planning Act of 1968.This "KIZON TAKUTl" was abolished by the amendment of the Town Planning Act in 2000. Under this situation, the present report discuss the cooperatively relation between urban and rural land use in the Town Planning Area.

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A new inventory control method reducing both the physical distribution cost and the inventory is proposed. This method obtained through the case study of a certain confectionery manufacturer has three basic functions : Selection of the transportation routes based on item characteristics, Allocation algorithm of the transportation volume to each regional distribution center, Function coping effectively with the change of item characteristics. The validity of the proposed method is shown by simulation results. The results denote that the physical distribution cost and the inventory are reduced to 89 % and 49 % respectively, comparing with the conventional ones. And the knowledge about system analysis/planning, which was obtained through the case study, is described.

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The purpose of this paper is to examine the mathematics textbooks in China mainly from the historical point of view and to consider the significance of putting the historical teaching materials in the mathematics textbooks. From the historical viewpoint one may say that the historical descriptions taken up in Chinese mathematics textbooks are almost restricted within what related to China herself. It is also emphasized that the most essential significance of putting the historical teaching materials in the textbook is for pupils to be encouraged and yearned to study mathematics.

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In August of 2002 13 Yokkaichi University students attended an environmental school at the University of Queensland in Australia. This paper summarizes the necessity for the environmental education in an institution of higher education and the advantages which this school has. This school provides practical environmental education. It is important for practical environmental education to master the knowledge of the basis and apply knowledge to the natural environment. By doing so, a student studies various broad areas, and has many experiences with the natural environment, and visits a lot of companies and organizations performing environmental preservation. When students have various knowledge and experiences, they can have a positive view of studying the environment. Furthermore, by staying in Australia for three weeks, they not only have international feeling, but they can have various views about society or life, and they can know the differences in the views of Australia and Japan. An institution of higher education should contribute to a student's future by providing a program which students are interesting such as Queensland University, Environmental School.

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