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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1598-1610页

作者： ito Tsuyoshi FENG Qinglai MATSUOKA Atsushi State Key Laboratory of Geo-processes and Mineral Resources China University of Geosciences Graduate School of Science and Technology Niigata University Research Institute of Geology and Geoinformation Geological Survey of Japan Department of Geology Faculty of ScienceNiigata University

The Permian planktonic distribution is not well known,in contrast to other fossil distributions of nekton and *** are representative microfossils of plankton in the Permian *** study compares both correlated radiolarian occurrences（Pseudotormentus De Wever et Caridroit and Quadriremis Nazarov et Ormiston） in literature data from the Pacific Rim and quantitative data from the Liuhuang and Gujingling sections in South *** distributions are concentrated in the Panthalassa,whereas Quadriremis occurrences are distributed over both the Panthalassa and the *** uneven distribution of Pseudotormentus seems to have been controlled by a difference in the oceanic basins,indicating the presence of faunal differences in Permian planktonic microorganisms between the Panthalassa and the *** other words,this study infers the provincialism of Permian planktonic *** uneven distribution is explainable by a hypothesis that Pseudotormentus was strongly affected by a Panthalassan equatorial current.

关键词： palaeobiogeography Palaeotethys Panthalassa Permian radiolaria Pseudotormentus Quadriremis

Effect of Flood Peak Discharge Control by a Small Reservoir in an Urbanized Area—Case Study in the Kurabe River Basin, Japan

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Open Journal of Modern Hydrology 2017年第4期7卷 314-330页

作者： Kouzo ito Manabu Segawa hiroshi Takimoto Toshisuke Maruyama Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

Recently severe damage of flooding by urbanization was frequently occurred. To prevent this damage, small reservoir was constructed in the urbanized residential area. This paper describes an effect of flood peak discharge control by a small reservoir (control reservoir) caused by rapidly developed urbanization. Although work for this purpose was conducted, research on the effects of the control reservoir was not conducted until now. This research, conducted by simulation, was a case study in the Kurabe River Basin in the Tedori River Alluvial Fan Area, Japan, based on the precise investigation of the reservoir in the actual field. The study was conducted to determine not only the actual control reservoir capacity for the newly developed residential area but also the ideal capacity for all present residential areas and the largest capacity allowable for a maximum rainfall event that recently occurred. The control reservoir effects between individual blocks and the entire basin area were compared by dividing the test basin into 15 blocks (sub-basins). The results showed that the effects on the capacity per unit area of the residential area in blocks have close relationship with the decreasing ratio of peak discharge in blocks. Consequently, the effects of control reservoir capacity and the limitation were clarified. In the future, control reservoirs should be constructed for all of the already developed residential areas, for example, by utilizing underground car parking lot. The results of this research can contribute to the design of the control reservoir for protection against flooding damage in urbanized areas.

关键词： Flood Control Reservoir Discharge from Urbanized Area Unit Flood Discharge Peak Discharge Decreasing Ratio Simulation of Drainage Discharge

Development of a Leg Mechanism for Soft Landing Based on Biological Motion

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 731-737页

作者： KIMURA Hitoshi OTAKI Yoshihiko ito Shusaku INOU Norio Department of Mechanical and Control Engineering Tokyo Institute of Technology NSK Ltd.

With jumping mechanisms,soft landing motion is important to protect loads and the *** study proposes a leg mechanism for soft landing based on biological *** jumping motion with a load suggests a unique motion for soft *** landing model consists of two *** is minimized in the first period and force is minimized in the second *** comparison with other landing models,this model is specialized for soft landing motion protecting an objective *** all mechanisms have mass,such model is useful in practical *** the purpose of realizing soft landing motion,this study proposes a new leg *** mechanism achieves quick variable transmission with cam and *** process of the cam is explained with dynamics and *** the calculated cam shape,the leg mechanism can be driven by constant input voltage for simple *** against height change is also verified with landing *** 50mm falling experiment,prototype leg mechanism performed soft landing without bounce motion and large *** acceleration profile of the body also agrees with the proposed soft landing model.

关键词： soft landing biological motion leg mechanism cam and wire mechanism

Electron field emission characteristics of nano-catkin carbon films deposited by electron cyclotron resonance microwave plasma chemical vapour deposition

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Chinese Physics B 2008年第2期17卷 716-720页

作者：顾广瑞吴宝嘉金哲 ito Toshimichi Department of Physics College of ScienceYanbian University Division of Electrical Electronic and Information EngineeringGraduate School of EngineeringOsaka University

This paper reported that the nano-catkin carbon films were prepared on Si substrates by means of electron cyclotron resonance microwave plasma chemical vapour deposition in a hydrogen and methane mixture. The surface morphology and the structure of the fabricated films were characterized by using scanning electron microscopes and Raman spectroscopy, respectively. The stable field emission properties with a low threshold field of 5V/μm corresponding to a current density of about 1μA/cm^2 and a current density of 3.2mA/cm^2 at an electric field of 10V/μm were obtained from the carbon film deposited at CH4 concentration of 8%. The mechanism that the threshold field decreased with the increase of the CH4 concentration and the high emission current appeared at the high CH4 concentration was explained by using the Fowler-Nordheim theory.

关键词： field emission carbon films nano-catkin microwave plasma chemical vapour deposition

Predicting Tensile Properties of Friction-Stir-Welded 6063 Aluminum with Experimentally Measured Welding Heat Input

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Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1235-1242页

作者： Tianbo Zhao Yutaka SSato Hiroyuki Kokawa Kazuhiro ito Department of Materials Processing Graduate School of EngineeringTohoku University6-6-02 Aramaki-aza-AobaSendai 980-8579Japan Joining and Welding Research Institute Osaka UniversityMihogaoka11-1IbarakiOsaka 567-0047Japan Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This work aims to develop a reliable method to predict mechanical properties of friction-stir-welded 6 xxx-series alloys with experimentally measured welding heat input. A calorimetrical method was utilized to experimentally measure the welding heat input in the friction stir welded of aluminum alloy 6063-T5. Good correlations between the input variables, i.e., welding parameters and physical properties of the materials, and the welding heat inputs obtained with experimental measurements were discovered. The welding heat input can be predicted using the empirical equation derived based on these correlations. Moreover, the results suggested that the thermal conductivities of the welded alloys affected the welding heat input significantly. Mechanical properties, including hardness and tensile properties, of friction-stir-welded aluminum alloy 6063 were in good correlation to the heat input obtained with experimental measurement. These correlations were explained by the evolution of the strengthening precipitates during welding. This work proposed a reliable new route to predict these mechanical responses through the estimation of heat input.

关键词： Heat input Friction stir welding Calorimetrical Mechanical properties Hardness

Application of Simple Adaptive Control to Water Hydraulic Servo Cylinder System

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 882-888页

作者： ito Kazuhisa YAMADA Tsuyoshi IKEO Shigeru TAKAHASHI Koji College of Systems Engineering and Science Shibaura Institute of Technology Saitama 3378570 Japan Graduate School of Mechanical Engineering Tottori UniversityTottori 6808552 Japan Department of Mechanical Engineering Sophia UniversityTokyo 1028554 Japan

Although conventional model reference adaptive control （MRAC） achieves good tracking performance for cylinder control, the controller structure is much more complicated and has less robustness to disturbance in real applications. This paper discusses the use of simple adaptive control （SAC） for positioning a water hydraulic servo cylinder system. Compared with MRAC, SAC has a simpler and lower order structure, i.e., higher feasibility. The control performance of SAC is examined and evaluated on a water hydraulic servo cylinder system. With the recent increased concerns over global environmental problems, the water hydraulic technique using pure tap water as a pressure medium has become a new drive source comparable to electric, oil hydraulic, and pneumatic drive systems. This technique is also preferred because of its high power density, high safety against fire hazards in production plants, and easy availability. However, the main problems for precise control in a water hydraulic system are steady state errors and overshoot due to its large friction torque and considerable leakage flow. MRAC has been already applied to compensate for these effects, and better control performances have been obtained. However, there have been no reports on the application of SAC for water hydraulics. To make clear the merits of SAC, the tracking control performance and robustness are discussed based on experimental results. SAC is confirmed to give better tracking performance compared with PI control, and a control precision comparable to MRAC （within 10 μm of the reference position） and higher robustness to parameter change, despite the simple controller. The research results ensure a wider application of simple adaptive control in real mechanical systems.

关键词： water hydraulics servo cylinder system positioning control simple adaptive control

Dynamics and geometry of developing planar jets based on the invariants of the velocity gradient tensor

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Journal of Hydrodynamics 2015年第6期27卷 894-906页

作者：吴楠楠 SAKAI Yasuhiko NAGATA Kouji ito Yasumasa School of Electric Power Engineering China University of Mining and Technology Department of Mechanical Science and Engineering Nagoya University

Based on the direct numerical simulation （DNS）, the developing planar jets under different initial conditions, e.g., the con- ditions of the exit Reynolds number and the exit mean velocity profile, are investigated. We mainly focus on the characteristics of the invariants of the velocity gradient tensor, which provides insights into the evolution of the dynamics and the geometry of the planar jets along with the flow transition. The results show that the initial flow near the jet exit is strongly predominated by the dissipation over the enstrophy, the flow transition is accompanied by a severe rotation and straining of the flow elements, where the vortex structure evolves faster than the fluid element deformation, in the fully-developed state, the irrotational dissipation is dominant and the most probable geometry of the fluid elements should remain between the biaxial stretching and the axisymmetric stretching. In addition, with a small exit Re and a parabolic profile for the exit mean streamwise velocity, the decay of the mean flow field and the magnitude of the turbulent variables will be strengthened in the process of the flow transition, however, a large exit Re will promote the flow transition to the fully-developed state. The cross-impact between the exit Re and the exit mean velocity profile is also observed in the present study.

关键词： planar jet direct numerical simulation (DNS) velocity gradient tensor flow transition joint probability density function(joint pdf)

Robust Monetary Framework for China

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China & World Economy 2006年第5期14卷 32-47页

作者： Takatoshi ito Faculty of Economics University of TokyoJapan.

China faces rising current account surpluses and foreign reserves. Maintaining the fixed exchange rate runs the risk of overheating of the economy. It is desirable to pursue greater flexibility of the exchange rate regime in the short run, and gradual liberalization of capital account transactions in the medium run. Proper sequencing of various steps is recommended to prevent financial crises. Japan＇s transition from the dollar peg to a more flexible exchange rate system in 1971-1973 is considered to be a mistake, whereas the gradual capital account opening from the mid-1970s to mid-1990s is considered a success. The present study also analyzes Korea＇s mistake in opening its capital markets too far ahead of exchange rate flexibility, and liberalizing short-term capital rather than long-term capital. The challenge before China is similar to Japan＇s of 1969-1970, in the sense that the transition from the dollar peg is inevitable and desirable for the country, but decisive actions with proper sequencing are important.

关键词： exchange rate regime Japan Korea capital account

Three-dimensional motion analysis for evaluating motor function in rodents with peripheral nerve injury

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Neural Regeneration Research 2019年第12期14卷 2077-2078页

作者： Akira ito Wang Tianshu Junichi Tajino Department of Motor Function Analysis Human Health Sciences Graduate School of Medicine Kyoto University Kyoto Japan Department of Development and Rehabilitation of Motor Function Human Health Sciences Graduate School of Medicine Kyoto University Kyoto Japan

Peripheral nerves act like networks of “wires” that conduct signals from the brain and spinal cord to organs throughout the body. Damage to these nerves leads to numbness, pain, and weakness that eventually reduces the patient’s quality of life. Fortunately, peripheral nerves have a high regenerative capacity and, in most cases, recover from mild disorders and injuries. However, there have been continuous challenges facing the development of treatments for peripheral nerve conditions such as disorders that occur through chronic mechanical stimulation like carpal tunnel syndrome, disorders due to side effects from drugs and intractable diseases like chronic inflammatory demyelinating polyneuropathy.

关键词： motion analysis function nerves

Protective effect of estradiol on hepatocytic oxidative damage

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World Journal of Gastroenterology 2002年第2期8卷 363-366页

作者： Ichiro Shimizu Toshihiro Omoya Susumu ito Second Department of Internal Medicine School of MedicineUniversity of TokushimaTokushima770-8503Japan

AIM: To examine the protective effect of estradiol on the cultured hepatocytes under oxidative stress. METHODS: Hepatocytes of rat were isolated by using perfusion method, and oxidative stress was induced by a serum-free medium and FeNTA. MDA level was determined with TBA method. Cell damage was assessed by LDH assay. Apoptosis of hepatocytes was assessed with cytoflowmetric analysis. Expression of Bcl-xl in cultured hepatocytes was detected by Western blot. The radical-scavenging activity of estradiol was valued by its ability to scavenge the stable free radical of DDPH. RESULTS: Oxidative stress increased LDH from 168 +/- 25 x 10(-6)***(-1) to 780 +/- 62 x 10(-6)***(-1) and MDA(from 0.28 +/- 0.07 x 10(-6)***(-1) to 1.35 +/- 0.12 x 10(-6)***(-1)) levels in cultured hepatocyte, and estradiol inhibited both LDH and MDA production in a dose dependent manner. In the presence of estradiol 10(-6)mol.L(-1), 10( -7 )mol.L(-1) and 10(-8)mol.L(-1),the LDH levels are 410 +/- 53 x 10(-6)***(-1) (P<0.01 vs oxidative group), 530 +/- 37 X 10(-6)***(-1 ) (P<0.01 vs oxidative group), 687+/-42 x 10(-6)***(-1) (P<0.05 vs oxidative group) respectively, and the MDA level are 0.71+/-0.12 x 10(-6)***(-1) (P<0.01 vs oxidative group),0.97+/-0.11 x 10(-6)***(-1 )(P<0.01 vs oxidative group) and 1.27+/-0.19 x 10(-6)***(-1) respectively. Estradiol suppressed apoptosis of hepatocytes induced by oxidative stress, administration of estradiol(10(-6)mol/L)decreased the apoptotic rate of hepatocytes under oxidative stress from 18.6 +/- 1.2% to 6.5 +/-2.5%, P<0.01. Bcl-xl expression was related to the degree of liver cell damage due to oxidative stress, and estradiol showed a protective action. CONCLUSION: Estradiol protects hepatocytes from oxidative damage by means of its antioxidant activity.

关键词： Oxidative Stress Animals Apoptosis Cells, Cultured Estradiol Female Flow Cytometry Hepatocytes L-Lactate Dehydrogenase Lipid Peroxidation Male Proto-Oncogene Proteins c-bcl-2 Rats Rats, Wistar Thiobarbituric Acid Reactive Substances bcl-X Protein