检索结果-南通市图书馆

Journal of Flow Control, Measurement & Visualization 2013年第3期1卷 86-93页

作者： Takayuki Yamagata Takuya Nagasawa Nobuyuki Fujisawa Takeshi Asai Institute of Health and Sports Sciences Tsukuba University Tsukuba Ibaraki Japan Visualization Research Center Niigata University Ikarashi Nishi-ku Niigata Japan

This paper describes the experimental method for evaluating the flight trajectory and the aerodynamic performance of a kicked non-spinning soccer ball. The flight trajectory measurement is carried out using the digital image analysis. A centroid method and a template matching method are tested for the flight trajectory analysis using the artificial images generated by the data of a free-fall experiment. The drag coefficient obtained by the centroid method is better suited for the sports ball experiment than that by the template matching method, which is due to the robustness of the centroid method to the non-uniform illumination. Then, the flight trajectory analysis is introduced to a kicked experiment for a non-spinning soccer ball. The experimental result obtained from the stereo observation indicates that the S-shaped variation is found in the three-dimensional flight trajectory and in the side force coefficient during the flight of the non-spinning soccer ball.

关键词： Non-Spinning Soccer Ball Fluid Force Flight Trajectory Measurement Stereo Image Analysis

Recently developed strategies to restrain dendrite growth of Li metal anodes for rechargeable batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2020年第6期39卷 616-635页

作者： Kai-Chao Pu Xin Zhang Xiao-Lei Qu Jian-Jiang Hu Hai-Wen Li Ming-Xia Gao Hong-Ge Pan Yong-Feng Liu State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China Platform of Inter/Transdisciplinary Energy Research(Q-PIT) International Research Center for Hydrogen EnergyInternational Institute for Carbon-Neutral Energy Research(I2CNER)Kyushu University744 MotookaNishi-kuFukuoka 819-0395Japan

Lithium metal has been regarded as one of the most promising anode materials for high-energy-density batteries due to its extremely high theoretical gravimetric capacity of 3860 mAh·g^-1 along with its low electrochemical potential of-3.04 ***,uncontrollable Li dendrite growth and repetitive destruction/formation of the solid electrolyte interphase layer lead to poor safety and low Coulombic efficiencies(CEs)for long-term utilization,which largely restricts the practical applications of lithium metal *** this review,we comprehensively summarized important progresses achieved to date in suppressing Li dendrite *** for protection of Li metal anodes include designing porous structured hosts,fabricating artificial solid electrolyte interface(SEI)layers,introducing electrolyte additives,using solid-state electrolytes and applying external *** protection of Li metal anodes can be achieved by regulating the stripping and deposition behaviours of Li ***,the challenges remaining for lithium metal battery systems and future perspectives for Li metal anodes in practical applications are outlined,which are expected to shed light on future research in this field.

关键词： Rechargeable batteries Anode materials Lithium metal Dendrite growth Coulombic efficiency

Another Collimation Mechanism of Astrophysical Jet

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science and Engineering 2017年第2期7卷 74-89页

作者： Yoshinari Minami Advanced Science-Technology Research Organization (Formerly NEC Space Development Division) 35-13 Higashikubo-ChoNishi-Ku Yokohama 220-0062 Japan

The acceleration mechanism of astrophysical jet and the collimation mechanism narrowing down to a long distance have been examined so far. It is a collimation problem of how to narrow the astrophysical jet narrowly. Further, the model of the astrophysical jet acceleration mechanism is required to solve this collimation problem at the same time as well as its acceleration. At the present time, the magnetic force model （magnetic centrifugal force and magnetic pressure） is regarded as the most dominant theory which solves the two problems of astrophysical jet acceleration and collimation at the same time. In addition to the present astrophysical jet narrow collimation mechanism by magnetic tension （pinch） force, in this article, another collimation mechanism which narrows down an astrophysical jet is newly introduced. That is, since a curvature is generated in the space around the astrophysical jet by magnetic field, a kind of pressure equivalent to the gravitational effect is generated in the direction of the interior of astrophysical jet as well as the pinch force from the outer circumferential surface of the astrophysical jet.

关键词： Astrophysical jet accretion disk black hole collimation mechanism acceleration mechanism magnetic field continuum curvature space-time cosmology.

Contributions of the Secondary Jet to the Tangential Velocity Distribution and to the Collection Efficiency of the Fixed Guide Vane Type Axial Flow Cyclone Dust Collector

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2015年第6期24卷 503-509页

作者： Akira Ogawa Hideki Anzou So Yamamoto Mituru Shimagaki 1.110-0011 Minowa 2-14-7 Taitou-Ku Tokyo Japan

In order to control the maximum tangential velocity V?m(m/s)of the turbulent rotational air flow and the collection efficiencyηc(%)using the fly ash of the mean diameter X R50=5.57?m,two secondary jet nozzles were installed to the body of the axial flow cyclone dust collector with the body diameter D1=*** in order to estimate V?m(m/s),the conservation theory of the angular momentum flux with Ogawa combined vortex model was *** comparisons of the estimated results of V?m(m/s)with the measured results by the cylindrical Pitot-tube were shown in good *** also the estimated collection efficienciesηcth(%)basing upon the cut-size Xc(?m)which was calculated by using the estimated V?m(m/s)and also the particle size distribution R(Xp)were shown a little higher values than the experimental results due to the re-entrainment of the collected *** best method for adjustment ofηc(%)related to the contribution of the secondary jet flow is principally to apply the centrifugal effect?c(1).Above stated results are described in detail.

关键词： Axial Flow Cyclone Dust Collector Maximum Tangential Velocity Cut-Size Particle Size Distribution Collection Efficiency Reynolds number Centrifugal Effect

Asian international grid connection and potentiality of DC superconducting power transmission

在线全文

学校读者我要写书评

暂无评论

Global Energy Interconnection 2018年第1期1卷 11-19页

作者： Satarou Yamaguchi Takashi Iitsuka Masashi Osada Ryuichi Yokoyama Chubu University Matsumoto-cho 1200Kasugai487-8500AichiJapan JGC Corporation Minato Mirai 2-3-1Nishi-kuYokohama 220-6001Japan ABB K.K. Ohsaki 2-1-1Shinagawa-ku141-6022 TokyoJapan Energy and Environment Technology Research Institute 1-22-2 Nishiwaseda Shinjuku169-0051 TokyoJapan

In 2011, a large scale earthquake and tsunami hit the northeastern coast of Japan, and nuclear plants were damaged to a large extent. Before the Tsunami, 54 nuclear plants were operated, however presently, only three nuclear plants are in operation. Therefore, Japan is suffering from high price of electricity and low supply reliability. In generation mix, nuclear plants generate only one percent and 87 percent of electricity is generated by fossil energy. This is not preferable for Japan from the viewpoints of energy security and stable electricity supply. Therefore, it is mandatory to increase sustainable energy and to decrease consumption of fossil fuel. International grid connection and the Global Energy Interconnection will be one of countermeasures against these problems existing in Japan. In this paper, international grid connection initiatives proposed in Asia are described and features and issues of electric power grids in Japan are discussed to implement the international grid connection. As the key technology for implementing the international grid connection, the present status of DC superconducting power transmission lines and power converters for long-distance power transmission lines are presented. In conclusion, conditions and legal frameworks for realizing the international grid connection are described.

关键词： International grid connection Global Energy Interconnection Sustainable energy DC superconducting Power converter

The Latest Study of Gravitational Wave Communication System

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science and Engineering 2016年第3期6卷 164-176页

作者： Yoshinari Minami Advanced Science-Technology Research Organization (Formerly NEC Space Development Division) 35-13 Higashikubo-ChoNishi-Ku Yokohama 220-0062 Japan

Gravitational wave is a strain wave of space and this can be also generated by strong magnetic field. The principle of gravitational wave generation using the fluctuation in strain field induced by magnetic field is introduced. Using both foregoing gravitational wave generator and gravitational wave detector （i.e. laser interferometric gravitational wave antenna）, the gravitational communication system can be possible. This paper introduces its content presented at 20th Annual Lecture （1989） and the research trends in the latest gravitational wave.

关键词： Gravitational wave space-time continuum space strain strain wave curvature gravitational wave communication.magnetic field.

Efficient Origin-Destination Estimation Using Microscopic Traffic Simulation with Restricted Rerouting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第5期135卷 1091-1109页

作者： Kazuki Abe Hideki Fujii Shinobu Yoshimura Vector Research Institute Inc.Shibuya-kuTokyo150-0002Japan School of Engineering The University of TokyoBunkyo-kuTokyo113-8656Japan

Traffic simulators are utilized to solve a variety of traffic-related *** such simulators,origin-destination(OD)traffic volumes as mobility demands are required to input,and we need to estimate *** authors regard an OD estimation as a bi-level programming problem,and apply a microscopic traffic simulation model to ***,the simulation trials can be computationally expensive if full dynamic rerouting is allowed,when employing multi-agent-based models in the estimation *** paper proposes an efficient OD estimation method using a multi-agent-based simulator with restricted dynamic rerouting to reduce the computational *** though,in the case of large traffic demand,the restriction on dynamic rerouting can result in heavier *** authors resolve this problem by introducing constraints of the bi-level programming problem depending on link *** results show that the accuracy of the link traffic volume reproduced with the proposed method is virtually identical to that of existing methods but that the proposed method is more computationally efficient in a wide-range or high-demand context.

关键词： ODestimation microscopic traffic simulation dynamic rerouting bi-level programming multi-agent basedmodel

Controllable fabrication of carbon aerogels

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2006年第z1期25卷 284-288页

作者： TANEMURA Sakae TANEMURA Masaki SUZUKI Kenzi Department of Environmental Technology & Urban Planning Nagoya Institute of Technology Showa-ku Nagoya 466-8555 Japan EcoTopia Science Institute Nagoya University Chikusa-ku Nagoya Japan

Nano-pore carbon aerogels were prepared by the sol-gel polymerization of resorcinol (1,3-dihydroxybenzene)(C6H4(OH)2) with formaldehyde (HCHO) in a slightly basic aqueous solution, followed by super-critical drying under liquid carbon dioxide as super-critical media and carbonization at 700 ℃ under N2 gas atmosphere. The key of the work is to fabricate carbon aerogels with controllable nano-pore structure, which means extremely high surface area and sharp pore size distribution. Aiming to investigate the effects of preparation conditions on the gelation process, the bulk density, and the physical and chemical structure of the resultant carbon aerogels, the molar ratio of R/C (resorcinol to catalyst) and the amount of distilled water were varied, consequently two different sets of samples, with series of R/C ratio and RF/W (Resorcinol-Formaldehyde to water, or the content of reactant) ratio, were prepared. The result of N2 adsorption/desorption experiment at 77 K shows that the pore sizes decreasing from 11.4 down to 2.2 nm with the increasing of the molar ratio of R/C from 100 to 400, and/or, the pore sizes decreasing from 3.8 down to 1.6 nm with the increasing of reactant content from 0.4 to 0.6.

关键词： resorcinol-formaldehyde aerogels carbon aerogels super-critical drying N2 adsorption/desorption

Characterization of landfilled stainless steel slags in view of metal recovery

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2017年第3期11卷 353-362页

作者： Xuan Wang Daneel Geysen Tom Van Gerven Peter T. Jones Bart Blanpain Muxing Guo Department of Metallurgy and Materials Engineering KU Leuven 3001 Heverlee Belgium Department of Chemical Engineering KU Leuven 3001 Heverlee Belgium Department of Research and Development Group Machiels 3001 Heverlee Belgium

The slag samples taken from landfill, which originated from different metallurgical processes, have been characterized in this study. The slags were categor- ized as electric arc furnace （EAF） slag, argon oxygen decarburization/metal refining process slag and vacuum oxygen decarburization slag based on chromium content and basicity. EAF slags have higher potential in metal recovery than the other two slags due to its higher iron and chromium contents. The size of the iron-chromium-nickel alloy particles varies from a few ~tm up to several cm. The recoveries of large metal particles and metal-spinel aggregates have potential to make the metal recovery from landfilled slags economically viable.

关键词： landfilled stainless steel slag metal recovery characterization

MicroGrid Designer:user-friendly design,operation and control assist tools for resilient microgrid and autonomous community

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Global Energy Interconnection 2022年第3期5卷 249-258页

作者： Ryuichi Yokoyama Yicheng Zhou Energy and Environment and Technology Research Institute and Waseda University 1-22-2 Nishi-Waseda ShinjukuNishi-Waseda East Wing 106Tokyo169-0051Japan

During this decade,many countries have experienced natural and accidental disasters,such as typhoons,floods,earthquakes,and nuclear plant accidents,causing catastrophic damage to *** the end of 2019,all countries of the world are struggling with the COVID-19 and pursuing countermeasures,including inoculation of vaccine,and changes in our lifestyle and social *** these experiences have made the residents in the affected regions keenly aware of the need for new infrastructures that are resilient and autonomous,so that vital lifelines are secured during calamities.A paradigm shift has been taking place toward reorganizing the energy social service management in many countries,including Japan,by effective use of sustainable energy and new supply ***,such new power sources and supply schemes would affect the power grid through intermittency of power output and the deterioration of power quality and ***,new social infrastructures and novel management systems to supply energy and social service will be *** this paper,user-friendly design,operation and control assist tools for resilient microgrids and autonomous communities are proposed and applied to the standard microgrid to verify its effectiveness and performance.

关键词： Microgrid Autonomous community Grid design and analysis Resilience Unit commitment Economic load dispatch Load frequency control Dynamic power flow Energy management system