The buoyant plume above a round heat source was analyzed through the computational simulation based on a weakly compressible Differential Second Moment closure model(DSM)/Differential heat Flux model. The reason why we are considering the fluid compressibility is that there is a very large difference of the temperature between the surface of the heat source and ambient air. The analyzed results were compared with Shabbir's plume-equations and plume-equations. The computational results(DSM) almost corresponded to Shabbir's plume-equations, but these didn't fitted with plume-equations.

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In order to clarify the preventive method of big fire in a built-up area of wooden houses, it is important to discuss the estimative method of temperature fields on the fire gas flow and the general behavior of the flame on big fire. This paper purposes to obtain a method of estimating the temperature distribution of fire gas on big fire. The author has considered fire spread and burning behavior on big fire, attempted to assume a belt-shaped heat source as the experimental model of burning area. The similarity theory in the case of the thermal convection from a belt-shaped heat source is derived by determining a few parameters appearing in this model. The experimental studies in the thermal convection from a line heat source was already performed by S. . The author has first begun to try the approximate solution in the case of a line heat source, and attempted to compare the results with case (transverse excess temperature and velocity distributions). The results of calculation fitted better to the equation. A mathematical model on the turbulent diffusion flames from a belt-shaped heat source was derived by a few parameters based on similarity analysis considered in the case of the approximate solution. In order to examine the theory considered in this paper, measurements of temperature and velocity were performed in a tunnel placed a belt-shaped vessel for burning alcohol. The measured temperature and velocity distribution was satisfied with the validity of the theory considered in this paper.

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Thermal plumes in wall free space were numerically simulated with the standard k- e model and the results were compared with the basic experiment which had been conducted by . The purpose of this study is to confirm the accuracy and reliability of the numerical simulation of thermal plumes from the view point of practical use of simulation for fire safety planning. The flow fields associated with various conditions concerning the computational domain, mesh dividing system and so on were simulated and compared with the formula in order to evaluate the accuracy and reliability of the CFD performance based on the standard k-ε model. The distributions of Cell Reynolds numbers gave us a good criteria for practically reliable simulations.

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Many scholars, in analyzing the concept of“public”in the intellectual history of Japan have centered their arguments around the problem of the concept of the“public and the private”(koshi or oyake to watakushi). However, in the case of Shonan (1809-1869), I wish to make a distinction between his concern with“the public”(kokyo) and his treatment of the “public and private.”It seems to me that placed centrality on“the public”and sought, especially after the arrival of Commodore Perry's“Black Ships, ”as a means to realize the idea of“the public”in Japanese society, economy, and politics.

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Counter pressure injection molding is a type of gas-assisted molding technology for preventing the generation of swirl marks by adding N₂ or CO₂ gas at high pressures of 1-15 MPa to the cavity. In this study, using a laser-light-sheet visualization mold, we visualized the movement of gas clouds and the bubble breakage phenomena at the flow front. The resin and gas used were general purpose polystyrene and N₂. First, we confirmed that the generation of gas cloud (as a result of gas condensation) can drastically be suppressed in the conventional injection molding process, even at a very low pressure of 0.7MPa. Secondly, in microcellular foam injection molding using supercritical fluid, the counter pressure method was found to reduce not only the nucleation of voids in the filling core layer and the subsequent fountain flow area, but also gas cloud generation with N₂ even at a low counter pressure of 1.0MPa. These visualization results clarify that low counter pressure is effective for empirically reducing both the gas cloud generation and the voids nucleation in supercritical foam injection molding.

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The present research focuses on “Engeiko” (1889) by

Tokifuyu, the first Japanese garden history text. Popular from the time of its publication throughout modern Japan, “Engeiko” has received mixed criticism based on later discoveries that have updated the knowledge on garden and garden texts. Through a careful reading and a thorough analysis of the text in connection with the relevant literature and the background of its publication, I reached the following main conclusions. First, in “Engeiko”, Tokifuyu mentions as many as 103 gardens and 177 texts (from garden textbooks to poetry collections), providing valuable information on the way gardens and garden texts were understood in the middle years of the Meiji period (1868-1912). Second, “Engeiko” shows a revolutionary approach to the historical discourse, in which the intention is to summarise the characteristic features of the gardens built in each historical period and identify the predominant garden styles. This approach is still common in today’ s Japanese garden history discourse, and in this paper it was named “periodical style discourse”. Based on the above, we can conclude that “Engeiko” plays an essential role in understanding the garden literature and craft, both in the Meiji period and today.

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The present note is a strengthening of a recent paper by K. Takazawa and Y.

(A generalized-polymatroid approach to disjoint common independent sets in two matroids, Discrete Mathematics (2019)). For given two matroids on E, under the same assumption in their paper to guarantee the existence of a partition of E into k common independent sets of the two matroids, we show that there exists a nearly uniform partition P of E into k common independent sets, where the difference of the cardinalities of any two sets in P is at most one.

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Analyzing outputs of seven climate models participating in the fifth phase of the Climate Model Intercomparison Project, this study performs multi-model projection of tropical cyclone (TC) genesis frequency over the Western North Pacific basin, with an emphasis on the spatial contrast. By evaluating reproducibility of the spatio-temporal distribution of the genesis frequency, we select five models to perform the multi-model projection. All five models and multi-model ensemble project eastward shift of the Main Development Region (MDR) of TCs located around the Philippines. This is probably caused by changes in dynamical environmental conditions such as lower-tropospheric relative vorticity and vertical shear of horizontal wind. Projected changes in the activity of tropical depression-type disturbances, which are candidates for seeds of TCs, may also contribute to the eastward shift. These projections are basically consistent with earlier results that and Takayabu (2009) obtained from outputs of a previous generation of climate model experiments. In addition, this study projects increases in the genesis frequency over a region east of Taiwan and the South China Sea, which are inconsistent with and Takayabu (2009).

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Brain Machine Interface 研究の方向性とリハビリテーション…里宇　明元　75

頭皮脳波を用いたBrain Machine Interface のリハビリテーション応用…牛場　潤一　79

低侵襲的Brain Machine Interface—リハビリテーションに何をもたらすか—…吉峰　俊樹，平田　雅之，柳澤　琢史，後藤　　哲，松下光次郎，齋藤　洋一，福間　良平，神谷　之康，横井　浩史　83

個性適応型情報処理を用いたロボット制御とその応用…横井　浩史，加藤　　龍　88

Brain Machine Interface：基礎神経科学から臨床応用へ…伊佐　　正　98

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Recently, the authors proposed a modified κ-ε model, applied it to flat plate boundary layer and stern flow, and improved prediction accuracy of mean flow field with longitudinal vortex. The modified κ-ε model is also applied to turbulent swirling flow in a straight pipe in order to express swirling flow more accurately. The modified κ-ε results are validated through comparisons with experiments, a standard κ-ε results, and a computational results for Nisizima-. The conclusion is that the modified κ-ε results show some improvements of tangential velocity W and reduction of axial velocity U near the core region.

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Measurement of shear stress distribution is important for examining phenomena occurring in the interface between the mold cavity surface and molten resin in injection molding. The authors developed a high precision measurement technique for shear stress distribution using a movable block and 3-component force transducer. In this study, we analyzed the influence of resins, cavity surface properties, and cavity thicknesses on shear stress distribution. The results are summarized below：

Ⅰ) Fluctuations were seen in the shear stress profile under some experimental conditions. These fluctuation phenomena were caused by delamination flow in the nozzle. They were removed by a digital filter to correct the shear stress profile.

Ⅱ) From typical experimental results, we proposed a model on the shear stress distribution near the flow front (“FF” hereafter). It consisted of (1) area which rises by rapid deformation just after the FF contacts the cavity surface, (2) area in which the shear stress remains constant due to the effects of shear viscosity and no solidified area forms, (3) area in which shear stress increases with the growth of the solidified layer, and (4) area in which shear stress remains a constant value due to the effects of shear heating and shear-thinning around the wall.

Ⅱ) The process by which characteristic phenomena occurred in various conditions was estimated as follows based on above model.

ⅰ) Area (2) became longer with increasing injection rate (IR) because the distance to be moved by the FF to cool down to form the solidified layer, increases with IR.

ⅱ) The larger the roughness of the cavity surface, the higher was the shear stress in areas (3) and (4) because the growth of the solidified layer is accelerated by the increase in the area contacting the resins on grained surfaces.

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Urethane foam mattresses were burnt in a room and the burning rate of the foam, the horizontal temperature and velocity distribution in the plume, and the descent speed of the smoke layer under the ceiling were measured. Then, the flame spread on the surface of the foam, the flame height, the smoke filling under the ceiling and the characteristics of the plume are discussed. Finally, the dimensionless temperature and the dimensionless velocity are calculated using the experimental data in comparison to 's results in his methanol experiment.

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It has been reported that there was some discrepancy between the values of the flame height, obtained from Thomas’ equation for the flame height and equation which is derived from the temperature distribution along the central axis of the upward current. The author studied this discrepancy and has now arrived at some conclusions, which are reported here.

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 Fire plume ejected from an opening tend to have a central axis of air current that rises closer to the wall surface as the cross-sectional shape of the opening (hereinafter , horizontal opening) becomes more horizontal. Fire plume ejected from such openings increase the potential risk of fire spreading to upper floors. Furthermore, fire plume from an opening may become longer due to increased thermal decomposition of combustible materials inside the compartment and the effect of pyrolysis gas burning outside the building.
 Currently in building design practice in Japan, the method proposed by is generally used when investigating measures for preventing the spread of fire to the upper floors due to fire plumes from openings in buildings. However, the opening conditions that examined covered aspect ratios n = 2W/H (W: width of opening; H: height of opening) of up to around 6.4, whereas the openings in modern buildings may have openings with aspect ratios greater than 6.4. Furthermore, although the amount of pyrolysis gas emitted from the opening is expected to increase with increased amounts of flammable material brought into the building, the method is unable to take into account such changes in the amount of pyrolysis gas.
 The focus of this research was therefore placed on the shape of the plumes of hot air under various flammable material conditions for openings with a horizontal shape. A series of experiments using a full-size compartment focusing on the shape of the temperature distribution in order to obtain knowledge related to the shape of the temperature distribution were conducted.
 In the experiment, we aimed to determine the temperature distribution above horizontal openings with aspect ratios of n = 5~20. The experimental apparatus consisted of a combustion compartment and a facade for modeling a room on fire. The dimensions of the combustion compartment were 4000[mm] wide × 4000[mm] deep × 1700[mm] high. The shape of the opening was fixed with opening widths of 2[m] and 3.7[m], and the opening aspect ratio was set in the range n = 5~20 in six sets of conditions for the opening width of 2[m] and three sets of conditions for the opening width of 3.7[m]. Three different fuels were used for the heat source: methanol, ethanol, and heptane.
 The following was found from this study.
 · Temperature attenuated with height Z above the opening to essentially the -1 power, the same as the gradient of the temperature distribution of the rectangular heat source.
 · The temperature distribution near the wall above the opening, nondimensionalized by taking T^* for the vertical axis and Q^*_(H-Zn)^-2/3z_(H-Zn)^* for the horizontal axis, exhibited a correlation with the temperature distribution of the rectangular heat source in free space when using the amount of heat Q_ef generated by pyrolysis gas.
 · Q_ef,max may underestimate the amount of heat generated by the pyrolysis gas. When Q_ef,crit was used, under the conditions where ethanol and heptane were used, the calculated and experimental values tended to match well.

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