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Effect of inclined ribs on heat transfer coefficient in stationary square channel

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Theoretical & Applied Mechanics Letters 2017年第6期7卷 344-350页

作者： Natthaporn Kaewchoothong Kittinan Maliwan kenichiro takeishi Chayut Nuntadusit Department of Mechanical Engineering Faculty of Engineering Prince of Songkla University Department of Systems Control Engineering Graduate school of Engineering Tokushima Bunri University

The main objective of this research is to study the effect of rib arrangement on the distributions of the local heat transfer coefficient in a stationary channel. In this study, the ribs with square cross section were used to place on two side walls for study. The rib height-to-hydraulic diameter ratio （e/Dh） and the rib pitch- to-height （p/e） ratio were fixed at 0.133 and 10, respectively. Three different types of rib arrangement for inclined ribs, V-shaped ribs and inverted V-shaped ribs were investigated. The rib angle of attack （α） was varied from 30° to 90° for inclined ribs and 45° and 60° for both V-shaped and inverted V-shaped ribs, and compared at constant Reynolds number Re =30000. Thermal Liquid Crystal sheet was applied for evaluating the heat transfer distributions. The results showed that the average Nusselt number on surface with rib inclined angle at 60°, 45°, and 60° V-shaped ribs was improved up to about 20%, 25% and 30% higher than case of angle 90° and the rib inclined angle at 60° V-shaped ribs provided the highest Nusselt number covering largest area when compared to the other cases.

关键词： Inclined ribslHeat transfer coefficientlThermal liquid crystal

Self-calibration and Compensation of Setting Errors for Surface Profile Measurement of a Microstructured Roll Workpiece

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 14-22页

作者： GAO Wei XU Bin takeishi Toshiki SHIMIZU Yuki ITO So Department of Nanomechanics Tohoku University School of Manufacturing Science and Engineering Sichuan University

Microstructured roll workpieces have been widely used as functional components in the precision industries. Current researches on quality control have focused on surface profile measurement of microstructured roll workpieces, and types of measurement systems and measurement methods have been developed. However, low measurement efficiency and low measurement accuracy caused by setting errors are the common disadvantages for surface profile measurement of microstructured roll workpieces. In order to shorten the measurement time and enhance the measurement accuracy, a method for self-calibration and compensation of setting errors is proposed for surface profile measurement of microstructured roll workpieces. A measurement system is constructed for the measurement, in which a precision spindle is employed to rotate the roll workpiece and an air-bearing displacement sensor with a micro-stylus probe is employed to scan the microstructured surface of the roll workpiece. The resolution of the displacement sensor is 0.14 nm and that of the rotary encoder of the spindle was 0.15r~. Geometrical and mathematical models are established for analyzing the influences of the setting errors of the roll workpiece and the displacement sensor with respect to the axis of the spindle, including the eccentric error of the roll workpiece, the offset error of the sensor axis and the zero point error of the sensor output. Measurement experiments are carded out on a roll workpiece on which periodic microstructures are a period of 133 i^m along the circumferential direction. Experimental results demonstrate the feasibility of the self-compensation method. The proposed method can be used to detect and compensate the setting errors without using any additional accurate artifact.

关键词： measurement profile setting error self-calibration compensation microstructure roll workpiece

Visual localization for asteroid touchdown operation based on local image features

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Astrodynamics 2020年第2期4卷 149-161页

作者： Yoshiyuki Anzai Takehisa Yairi Naoya takeishi Yuichi Tsuda Naoko Ogawa The University of Tokyo Tokyo113-8654Japan RIKEN Center for Advanced Intelligence Project Tokyo103-0027Japan Japan Aerospace Exploration Agency Sagamihara252-5210Japan

In an asteroid sample-return mission,accurate position estimation of the spacecraft relative to the asteroid is essential for landing at the target *** the missions of Hayabusa and Hayabusa2,the main part of the visual position estimation procedure was performed by human operators on the Earth based on a sequence of asteroid images acquired and sent by the *** this approach is still adopted in critical space missions,there is an increasing demand for automated visual position estimation,so that the time and cost of human intervention may be *** this paper,we propose a method for estimating the relative position of the spacecraft and asteroid during the descent phase for touchdown from an image sequence using state-of-the-art techniques of image processing,feature extraction,and structure from *** apply this method to real Ryugu images that were taken by Hayabusa2 from altitudes of 20 km-500 *** is demonstrated that the method has practical relevance for altitudes within the range of 5-1 *** result indicates that our method could improve the efficiency of the ground operation in the global mapping and navigation during the touchdown sequence,whereas full automation and autonomous on-board estimation are beyond the scope of this ***,we discuss the challenges of developing a completely automatic position estimation framework.

关键词： visual navigation structure from motion asteroid touchdown Hayabusa2

Hydrogen Production with Steam Reforming of Dimethyl Ether

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复旦学报（自然科学版） 2005年第5期44卷 721-722页

作者： Kaoru takeishi Akane ARASE Department of Materials Science and Engineering Shizuoka University Hamamatsu 432-8561 JapanDepartment of Materials Science and Engineering Shizuoka University Hamamatsu 432-8561 Japan

Steam reforming of methanol and gasoline is actively researched and developed as hydrogen supply methods for the fuel cells of vehicles and so on. However, these materials have the problems such as the infrastructure, toxicity, difficulty of the reforming, and so forth. Dimethyl ether (DME) does not contain the poisonous substances, and is expected as a clean fuel of the next generation. DME is able to take the place of light oil and LPG, and its physical properties are similar to those of LPG. There is possibility that DME infrastructures will be settled more rapidly than those of hydrogen and methanol, because LPG infrastructures existing are able to use for DME. Then, we have been studying on steam reforming of DME for the hydrogen production.

关键词：氢元素蒸汽转化二甲基醚催化剂氧化铝

Developments of Catalysts for Hydrogen Production from Dimethyl Ether

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复旦学报（自然科学版） 2007年第5期46卷 579-页

作者： Kaoru takeishi Department of Materials Science and Chemical Engineering Shizuoka University

1 Results Dimethyl ether (DME) is expected as a clean fuel of the 21st century.I have developed new catalysts for hydrogen production by steam reforming of ***-Zn/Al2O3 catalysts prepared by the sol-gel method produce large quantities of H2 and CO2 by DME steam reforming under lower reaction temperature[1].However,the sol-gel catalysts will be more expensive than general catalysts prepared by impregnation methods and coprecipitation methods,because the precursor,alkoxides are very *** pract...

关键词： dimethyl ether DME hydrogen catalyst steam reforming copper sol-gel alumina

Electrohydraulic lithotripsy and rendezvous nasal endoscopic cholangiography for common bile duct stone: A case report

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World Journal of Clinical Cases 2019年第10期7卷 1149-1154页

作者： Koichi Kimura Kensuke Kudo Tomoharu Yoshizumi Takeshi Kurihara Shohei Yoshiya Yohei Mano Kazuki takeishi Shinji Itoh Noboru Harada Toru Ikegami Tetsuo Ikeda Department of Endoscopy and Endoscopic Surgery Fukuoka Dental CollegeFukuoka 814-0175Japan Department of Surgery and Science Graduate School of Medical SciencesKyushu UniversityFukuoka 812-8582Japan

BACKGROUND In patients with large stones in the common bile duct(CBD),advanced treatment modalities are generally ***,we present an interesting case of a huge CBD stone treated with electrohydraulic lithotripsy(EHL)by the percutaneous approach and rendezvous endoscopic retrograde cholangiography(ERC)using a nasal *** SUMMARY A 91-year-old woman underwent ERC for a symptomatic large CBD stone with a diameter of 50 *** was referred to our institution after the failure of lithotomy by ERC,and after undergoing percutaneous transhepatic biliary *** attempted to fragment the stone by transhepatic cholangioscopy using ***,the stones were too large and partly soft clay-like for ***,we attempted lithotomy with ERC and cholangioscopy by the rendezvous technique using a nasal endoscope and achieved complete *** complication was observed at the end of this *** Cholangioscopy by rendezvous technique using a nasal endoscope is a feasible and safe endoscopic method for removing huge CBD stones.

关键词： Common bile duct stone Electrohydraulic lithotripsy Rendezvous technique Endoscopic retrograde cholangiography Nasal endoscop Case report

FRICTION COEFFICIENT OF CLUSTER DIAMOND-DISPERSED ALUMINUM COMPOSITE BY COMPRESSION SHEARING METHOD

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FRICTION COEFFICIENT OF CLUSTER DIAMOND-DISPERSED ALUMINUM C...

Prognostic factors in heart failure patients with cardiac cachexia

作者： Noboru Nakayama Hiroyuku takeishi Dept. of Machine Intelligence and Systems Eng. Akita Prefectural UniversityYurihonjyo Akita 015-0055 JAPAN Dept.of Science and Mech.Eng. Chiba Inst. of Thech. NarashinoChiba 275-8588 JAPAN

＜正＞In this paper, pure Aluminum and cluster diamond-dispersed aluminum composites were made by the compression shearing method. The friction coefficient, density, mechanical properties, and microstructures of compacted powders were investigated. The addition of 1vol. % CD to Al improved the friction coefficient. The average friction coefficients of Al, 1 vol. % CD sample, and 5vol. % CD sample indicate 0.91, 0.71 and 0.83, respectively. Comparing with one of Al, these values are reduction of 22% and 9% , respectively. However, the 5vol % CD solidified by compression shearing method and dynamic compaction method shows an increase in friction coefficient. The pores can be observed at 5% CD sample. It is considered that the lubricating ability of the Al composite containing 5% CD decreases by the pores, consequently the friction coefficient is increased. In compression shearing, the oxidation layer formed on the Al powder surface was destroyed. However, the bonding of the powders was lower in hot press and dynamic compacting, since it was not possible to sufficiently destroy the oxidation layer. Therefore, the friction coefficient of composite material molded by compression shearing is lower than the one of composite material molded by hot press and dynamic compacting.

关键词： Cluster diamond Friction properties Compression shearing method

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Journal of Geriatric Cardiology 2020年第1期17卷 26-34页

作者： Yu Sato Akiomi Yoshihisa Yusuke Kimishima Tetsuro Yokokawa Satoshi Abe Takeshi Shimizu Tomofumi Misaka Shinya Yamada Takamasa Sato Takashi Kaneshiro Masayoshi Oikawa Atsushi Kobayashi Takayoshi Yamaki Hiroyuki Kunii Yasuchika takeishi Department of Cardiovascular Medicine Fukushima Medical UniversityFukushimaJapan Department of Advanced Cardiac Therapeutics Fukushima Medical UniversityFukushimaJapan

Objective To clarify whether cardiac cachexia(CC)alters the prognostic impact of other general risk factors in patients with heart failure(HF).Methods This was an observational *** was defined as the combination of a body mass index of5 mg/L;hemoglobin<12 g/dL;and/or albumin<3.2 g/d *** divided 1608 hospitalized HF patients into a CC group(n=176,10.9%)and a non-CC group(n=1432,89.1%).The primary endpoints were cardiac event and all-cause *** The presence of CC showed significant interactions with other risk factors including cancer,estimated glomerular filtration rate(eGFR),and sodium in predicting these *** Cox proportional analysis revealed that use of a blockers[hazard ratio(HR)=1.900,95%confidence interval(CI):1.045–3.455,P=0.035]and eGFR(HR=0.989,95%CI:0.980–0.998,P=0.018)were independent predictors of cardiac event in the CC group,while age(HR=1.020,95%CI:1.002–1.039,P=0.029)and hemoglobin(HR=0.844,95%CI:0.734–0.970,P=0.017)were independent predictors of all-cause *** survival classification and regression tree analysis showed the optimal cut-off points for cardiac event(eGFR:59.9 m L/min per 1.73 m^2)and all-cause death(age,83 years old;hemoglobin,10.1 g/dL)in the CC *** In predicting prognosis,CC showed interactions with several risk *** function,age,and hemoglobin were pivotal markers in HF patients with CC.

关键词： Body mass index Cachexia Heart failure Mortality Prognosis

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辽宁双台河口黑嘴鸥的迁徙模式与种群生存率

生态学报 2010年第15期30卷 4180-4186页

作者：江红星侯韵秋李玉祥 Masayoshi takeishi Kiyoaki OZAKI 杨玉成郑光美中国林业科学研究院森林生态环境与保护研究所国家林业局森林保护学重点实验室北京100091 北京师范大学生命科学学院生物多样性与生态工程教育部重点实验室北京100875 辽宁双台河口国家级自然保护区辽宁盘锦市124010 九州市自然历史博物馆日本福冈县北九州市八幡区西本町3-6-1 北九州市8050061 鸟类迁徙研究中心日本山阶鸟类研究所日本千叶县我孙子市高野山115 我孙子市2701145

1996-2008年6月份,对辽宁双台河口国家级自然保护区黑嘴鸥使用特定编码的彩色旗标,共标记2820只。其中成鸟31只,幼鸟2789只。根据23个越冬地点2729条彩色旗标的重见记录,推测辽宁双台河口黑嘴鸥的迁徙路线主要有两条:一条向东迁徙至韩... 详细信息

1996-2008年6月份,对辽宁双台河口国家级自然保护区黑嘴鸥使用特定编码的彩色旗标,共标记2820只。其中成鸟31只,幼鸟2789只。根据23个越冬地点2729条彩色旗标的重见记录,推测辽宁双台河口黑嘴鸥的迁徙路线主要有两条:一条向东迁徙至韩国西南沿海及日本西部沿海越冬;另一条向南迁徙至我国天津以南的东部沿海,包括台湾西部沿海越冬。依据1996-2007年双台河口标记的黑嘴鸥幼鸟当年在日本西部沿海重见记录,计算12a间其相对生存率为(7.77±4.00)%(1.67%-14.89%)。其中1997、2001、2004、2006和2007年的相对生存率均低于平均水平,特别是2006年达到12年来的最低值(1.67%)。采用MARK软件中的Cormack-Jolly-Seber(CJS)模型,估计黑嘴鸥亚成体和成体的年生存率分别为0.613±0.058和0.746±0.042,重见率分别为0.897±0.04和0.799±0.053。亚成体较成体的重见率高,可能与亚成体到达越冬地相对比较集群有关。同时建议开展更多的彩色旗标观察活动,便于进一步了解同一越冬地中不同年龄段黑嘴鸥的移动规律。

关键词：黑嘴鸥(Larus saundersi) 彩色标记迁徙规律种群生存率辽宁双台河口