Observation of B̅0→D(*)0pp̅

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モンスーンアジアにおける地表面変化と気候・水循環変動 : 統合的国際共同研究

GAME観測データや長期客観解析データにもとづいて、ユーラシア大陸における植生と気候の季節変化における相互作用、大陸スケール広域水循環の数年周期の東西振動、積雪の季節変化と熱収支、チベット高原における地表面変化と大気加熱変化、対流活動変動と広域アジアモンスーン変動の季節内変動の関係、およびモンスーンアジアの広域および流域スケールでの水循環変化などの解明が行われた。また、TRMM-PRの高解像の衛星観測データの解析により、モンスーンの熱源域である西部熱帯太平洋から東南アジアにおける、降水量の日変化変動の時空間特性とその地表面状態との関連が明らかにされた。モデルによる研究では、領域大気モデルにより、インドシナ半島やスマトラ地域に顕著な対流活動の日変化特性と海陸分布、地表面状態、地形との関連に、新しい知見が得られた。東アジアでは、陸面の乾湿状態が梅雨前線のメソシステムの発達に密接に関与していることが、データ解析とモデルにより示された。大気大循環モデルでの研究では、チベット高原と植生分布の有無が、アジアモンスーンの成立にどの程度寄与しているかについての実験を行い、植生の存在が高原の地形効果同様、モンスーンの成立に重要であることが明らかにされた。さらに、東南アジアモンスーンにおけるチベット高原と海面水温の相対的役割の評価、中国の水田が梅雨前線活動に与える影響、梅雨前線の成立に果たすチベット高原や土壌水分などの地表面状態の役割等が、いくつかの気候モデルを用いて明らかにされた。これらの観測およびモデルによる研究成果は、Scienceを含む国際的学術雑誌に、すでに200編以上が受理、または印刷がなされている。本年度は最終年度として、これらの成果発表を含む第6回GAME国際研究集会を京都で開催した結果、180名の出席、約150編の研究発表があり、今後の研究の展望の議論が活発になされた。科学研究費補助金 研究種目:基盤研究(A) 課題番号:14204044 研究代表者:安成哲三 研究期間:2002－2004年度research repor

Dynamic Behavior of Gas Permeation in Solid Polymer Electrolyte Membranes*

application/pdfThe permeabilities of ethylene, propylene and carbon dioxide through various solid polymer electrolyte (SPE) membranes such as Nafion 417 (N-417), Asahikasei K-101 and A-201 and metal ion modified membranes have been compared at temperature ranges 0?80℃, using a flow-type diffusion cell newly developed for gas permeation under atmospheric pressure. K-101 and A-201 give no reproducibility of the permeability because of the cracks irreversibly formed on the membranes during the diffusion of gases, whereas N-417 gives a good reproducibility despite a small amount of permeability. On the silver-supported membrane, the permeabilities of C_2H_4 and C_3H_6 are clearly enhanced 2?3 times even though CO_2 is reduced to one third, and this is suggested by the formation of silver-olefin complexes which work as a pump to carry olefin gas. On the nickel-supported membranes, permeability is always reduced because the ion channel of the membrane for gas diffusion is diminished by the metal ions.departmental bulletin pape

A Study on Controller Design Method To Achieve High Control Bandwidth Using Frequency Response Data Sets

application/pdf三重大学大学院 工学研究科 博士前期課程 電気電子工学専攻 電機システム研究室63pthesi

ブブン カンソク システム ドウテイ ノ オウヨウ ト ノウガタ ジョウホウ ショリ ニ カンスル ケンキュウ

奈良先端科学技術大学院大学博士(理学)doctoral thesi

Experiment 2: Spatial shift of arrival ratios across dial positions.

<p>Underlying stimulus motion determines the position of the meeting point of the two traveling waves in both directions. Stimulus speeds in angular degrees per second are denoted along the ordinate, dial position along the abcissa. Gray lines are 9% iso-probability lines, the 3D profile is shown in the top-right inset. The black dashed line represents the line of equal μ of the best-fitting cumulative Gaussian in three dimensions. At stimulus speeds greater than approximately 75°/s in either direction the responses are dominated by the stimulus motion. In these cases, almost no reports of the traveling wave arriving in the direction opposite to the carrier grating motion occurred, even for the most extreme dial position. This means that the traveling wave moved more than three times faster in the direction of the carrier grating motion than it did in the opposite direction. Data points are the mean of 4 subjects. Inset 3D plot of the same data. The red line depicts data from the range used in experiment 1. These data mirror the data shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000739#pone-0000739-g002" target="_blank">figure 2A</a>, showing that in the range of stimulus motion used in experiment 1 the results of experiment 2 show identical trends.</p

Stimuli and Trial sequence.

<p>A. Stimuli. The stimuli used in experiments 1, 2&3. Stimulus motion was varied so that speeds were equal yet opposite in both eyes to produce symmetry across the eyes. Grating orientation was also opposite in both eyes. In exp. 1, the dial position was fixed at the top of the stimulus, whereas in exp. 2, the mark was placed at different positions around the entire upper half of the stimulus. B. Trial sequence. Subjects initiated the trials by depressing the space bar and ended them by releasing the space bar. First, the lower contrast half-image (carrier grating) was shown for 500 ms. Then, the higher contrast half-image (mask grating) was projected into the other eye, causing immediate perceptual dominance of the high-contrast mask annulus due to its higher contrast and the sudden onset of presentation. After another 500 ms, a 300 ms trigger in the lower contrast carrier grating annulus was used to initiate a wave-like transition at the 6 o'clock position that propagated upward in both directions across the annular stimulus. This strict timing sequence allowed precise control over the order of subjects' perceptual state during a trial.</p

Computational model: connectivity and simulations.

<p>We adapted the model by Wilson et. al. (3) which incorporates spatially extended interocular inhibition and collinear facilitation, properties of the functional connectivity within striate cortex. A The model consists of two layers of cells, each of these layers receives input from one eye. Each cell interacts with neighboring cells in its own layer (collinear facilitation, +) and negatively interacts with retinotopically nearby cells in the opposing layer via inhibitory interneurons (−). B Illustration of the shape of excitatory (gray solid lines) and inhibitory (dashed lines) influences exerted by the layer that represents the Carrier -(<i>C</i>)- neurons. Stimulus motion causes an asymmetry in the inhibitory profile impinging on the Mask -(<i>M</i>)- neurons (green dashed curve), where a standstill stimulus causes a symmetric inhibition profile (red dashed curve). This direction-selective inhibition acts on the <i>M</i>-neurons, specifically those neurons that code for the opposite direction of motion. Thus, the increase of inhibition impinging on the <i>M</i>-neurons due to the rising activity of <i>C</i>-neurons is biased in the direction of the motion of the carrier grating. C The course of binocular rivalry traveling waves under the influence of stimulus motion, as predicted by the model. With greater stimulus speeds, the asymmetry of motion in the different directions increases and the traveling wave duration decreases. The top and bottom of the figures represent the bottom of the annular stimulus, and the sample positions used in experiment 2 are shown at the ordinate. Clearly, the point of arrival under conditions of the higher stimulus speeds lies farther than the 90° mark, meaning that the model accurately reproduces the psychophysical data. The bottom figure that represents a traveling wave under the influence of a high level of stimulus motion has a ratio between clockwise and counter-clockwise inhibition width of 4∶1.</p

Ongoing rivalry compared with rivalry at onset.

<p><b>A</b>) In all four experiments we found an opposite influence of pre-exposure on rivalry at onset and ongoing rivalry (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030595#pone-0030595-g002" target="_blank">fig. 2A</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030595#pone-0030595-g003" target="_blank">3B</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030595#pone-0030595-g004" target="_blank">4B</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030595#pone-0030595-g005" target="_blank">5B</a>). At onset the alternative percept is suppressed (i.e. there is perceptual stabilization), whereas during ongoing rivalry the alternative percept is facilitated. As an illustration, the graph shows data from Experiment 2, condition with 4.3 minutes of ambiguous pre-exposure (see also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030595#pone-0030595-g003" target="_blank">fig. 3B</a>). <b>B</b>) Idiosyncratic perceptual biases in the baseline condition without pre-exposure, given as the percentage that the rightward percept is seen, or, concerning the eye bias in Experiment 4, the right eye is used. The table presents the mean difference from 50% of the individual biases (i.e. a value of 10% in the table refers to a bias of either 40% or 60%). Biases were high at onset and very small during ongoing rivalry. The graph shows the bias at onset and during ongoing rivalry for the individual participants in all four experiments. The ongoing biases are all small (ranging from 39% to 61%), but correlated positively with the bias at onset (which ranged from 0% to 100%) for Experiment 1, Experiment 3 and the eye bias in Experiment 4 (indicated with green symbols).</p

Experiment 3 and occlusion situation.

<p>A. Effect of stimulus grating collinearity on the influence of stimulus motion on the traveling wave. In our model a change in spiral angle, i.e. the collinearity of the pattern, is represented by a change in excitatory influence on neighboring neurons in the same layer, whereas this change in spiral orientation causes the effects of stimulus motion to diminish. Simulations showed that these different elements jointly act in such a way that the influence of stimulus motion is hampered. We tested this prediction directly by changing the spiral angle of both carrier and mask gratings while keeping the angular velocity of rotational motion equal at 23°/s. Data from three subjects clearly confirms the prediction of a negative effect of stimulus grating collinearity on the influence of stimulus motion. The black solid line represents the mean across subjects (colored lines), error bars are ±1 SEM. B. Diagram of the functional relevance of the implementation of asymmetric inhibition. The figures represent a top view of a binocular occlusion situation at two times, <i>t. A moving object may be occluded in one eye (R, <i>t</i>) and visible in the other (L, <i>t</i>). Direction-selective inhibition of the right-eye neurons in the path of the motion that is visible in the left eye allows direction-selective right-eye neurons to respond earlier to the appearance of the target moving leftward at <i>t</i>.</i></p