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Research on proximity effect of electromagnetic railgun

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Defence Technology（防务技术） 2016年第3期12卷 223-226页

作者： Yu-tao LOU Hai-yuan LI Bao-ming LI National Key Laboratory of Transient Physics Nanjing University of Science and Technology

The rails of electromagnetic railgun can be ablated by the temperature rise due to current *** current distributions on the rails and armature are not only affected by the skin effect,but also influenced by the proximity effect which is rarely *** paper illustrated the difference between skin effect and proximity effect,and the influencing factors of proximity effect were *** show that the current is concentrated on the surface around rails due to the skin effect,and the proximity effect exacerbates the current density on the inner surfaces of *** in distance from rails enhances the proximity effect,but has nothing to do with the skin effect,which also augments the rail resistance,resulting in temperature *** can explain the reason why the ablation is often detected in the small caliber *** results in this paper can provide support for design and optimization of electromagnetic railgun.

关键词： Electromagnetic railgun proximity effect Skin effect Ablation

On Finite-Time Anti-Saturated proximity Control with a Tumbling Non-Cooperative Space Target

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Space(Science & Technology) 2023年第1期3卷 348-361页

作者： Caisheng Wei Yang Li Zeyang Yin Liang Zhou Jinglang Feng School of Automation Central South UniversityChangshaChina Intelligent Science&Technology Academy Limited of CASIC BeijingChina Department of Mechanical and Aerospace Engineering University of StrathclydeGlasgowUK

For the challenging problem that a spacecraft approaches a tumbling target with non-cooperative maneuver,an anti-saturated proximity control method is proposed in this ***,a brand-new appointed-time convergent performance function is developed via exploring Bézier curve to quantitatively characterize the transient and steady-state behaviors of the pose tracking error *** major advantage of the proposed function is that the actuator saturation phenomenon at the beginning can be effectively ***,an anti-saturated pose tracking controller is devised along with an adaptive saturation ***,the finite-time stability of both the pose and its velocity error signals are guaranteed simultaneously in the presence of actuator ***,2 groups of illustrative examples are organized and verify that the close-range proximity is effectively realized even with unknown target maneuver.

关键词： saturated saturation proximity

Ethical Leadership and Moral Imagination: A Moderated Mediation Model of proximity and Organizational Commitment

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学术界 2019年第5期 191-202页

作者： Jiang Xiaochuan Yang Jianfeng College of Political Science and Law Jiangxi Normal University Nanchang Jiangxi 330022 Research Center of Cluster and Enterprise Development Jiangxi University of Finance and Economics Nanchang Jiangxi 330013

Moral imagination is the ability that can help individuals overcome constraints of organizational mental models to develop fresh frameworks and to make ethical decisions on the basis of those *** study aimed to explore the moderated mediator role of organizational commitment between ethical leadership and moral *** of 281 employees were collected,and results showed that when the victim of a certain ethical issue is their own company,organizational commitment fully mediated the effect of ethical leadership on moral imagination;however,when the victim is other company,ethical leadership and organizational commitment hadn't any effect on moral *** results showed the process that ethical leadership uses to influence moral imagination is not a social learning process but a social exchange process.

关键词： ethical leadership moral imagination proximity ethical decision making

Ultrafast miniaturized GaN-based optoelectronic proximity sensor

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Photonics Research 2022年第8期10卷 1964-1970页

作者： XIAOSHUAI AN HONGYING YANG YUMENG LUO ZHIQIN CHU KWAI HEI LI School of Microelectronics Southern University of Science and TechnologyShenzhen 518055China Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina School of Biomedical Sciences The University of Hong KongHong KongChina Engineering Research Center of Integrated Circuits for Next-Generation Communications Ministry of EducationSouthern University of Science and TechnologyShenzhen 518055China Engineering Research Center of Three Dimensional Integration in Guangdong Province Southern University of Science and TechnologyShenzhen 518055China

In this work, a novel ultrafast optoelectronic proximity sensor based on a submillimeter-sized GaN monolithic chip is presented. Fabricated through wafer-scale microfabrication processes, the on-chip units adopting identical In Ga N/Ga N diode structures can function as emitters and receivers. The optoelectronic properties of the on-chip units are thoroughly investigated, and the ability of the receivers to respond to changes in light intensity from the emitter is verified, revealing that the sensor is suitable for operation in reflection mode. Through a series of dynamic measurements, the sensor is highly sensitive to object movement at subcentimeter distances with high repeatability. The sensor exhibits ultrafast microsecond response, and its real-time monitoring capability is also demonstrated by applying it to detect slight motions of moving objects at different frequencies, including the human heart rate, the vibration of the rotary pump, the oscillation of the speaker diaphragm, and the speed of the rotating disk. The compact and elegant integration scheme presented herein opens a new avenue for realizing a chip-scale proximity sensing device, making it a promising candidate for widespread practical applications.

关键词： proximity sized rotating

ArcGIS<sup>TM</sup>proximity and Cluster Analysis of Electron Probe Micro-Maps of Round Top Critical Mineral Deposit

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Advances in Materials Physics and Chemistry 2020年第3期10卷 63-76页

作者： Lorraine M. Negrón Margaret Piranian Maria A. Amaya Daniel Gorski Nicholas E. Pingitore Department of Geological Sciences The University of Texas at El Paso El Paso Texas USA School of Nursing The University of Texas at El Paso El Paso Texas USA Texas Mineral Resources Corporation Sierra Blanca Texas USA

Critical and rare earth elements are in high demand for their increasing incorporation in modern technological devices for applications in the military, industrial, commercial, and consumer sectors. Round Top Mountain, a rhyolite laccolith in Sierra Blanca, west Texas, U.S.A. is a unique mineral deposit that offers opportunity for development of rare earth elements, especially the heavy rare earths, as well as associated critical elements. The main objective here is to evaluate the distances between accessory minerals of potential economic value (yttrofluorite, cryolite, uraninite, thorite, cassiterite, and columbite), and to major (potassium feldspar, albite, and quartz) and minor minerals (annite mi-ca, magnetite, and zircon). In this study we explore the proximity and clustering of these minor and accessory minerals, at the mi-cron-to-millimeter scale, from mineral maps constructed in a previous application of ArcGISTM tools to electron probe microanal-ysis (EPMA) element maps. Our goal is to determine whether specific minerals cluster spatially and, if so, at what distances. We noted that the high-value target yttrofluorite grains often neighbor potassium feldspar and quartz grains, but less commonly magnetite and mica grains. With regard to cluster analysis, most minor and accessory minerals were found to group together at small scales (low micrometer) and were dis-persed or random at larger (up to 1 mm) distances.

关键词： ArcGISTM EPMA proximity Ripley’s K-Function Critical Minerals Yttro-fluorite Round Top Deposit

proximity and Framing in News Media： Effects on Credibility, Bias, Recall, and Reader Intentions

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Journalism and Mass Communication 2012年第7期2卷 748-757页

作者： Joshua DeLung Robert G. Magee Rachel DeLauder Roxana Maiorescu Virginia Tech Blacksburg USA

A writer＇s decision to localize a news article and the valence of the frame the writer employs can affect readers＇ perceptions of credibility and bias as well as readers＇ factual recall and the likelihood that readers would want to read the newspaper further. A 2 （proximity： local, non-local） ~ 3 （frame valence： positive, neutral, negative） factorial experiment （N = 136） tested the effects of proximity and frame valence on credibility, perceived bias, recall, and reading intentions. Articles that localized enjoyed greater perceptions of credibility but not recall, while articles with either a positive or negative frame yielded greater recall than articles with a neutral frame. Neither factor exhibited a main effect in predicting perceived bias, but their interaction was a significant predictor. In addition, localization and frame valence also influence the likelihood that participants would want to read the source newspaper again. Implications for theory and media practice are discussed.

关键词： journalism news values framing proximity credibility

China＇s regional transport dominance： Density, proximity, and accessibility

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Journal of Geographical Sciences 2010年第2期20卷 295-309页

作者： JIN Fengjun WANG Chengjin LI Xiuwei WANG Jiao＇e Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects： quafity, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal：（1） Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. （2） Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level.

关键词： transport dominance density proximity accessibility China

A Study on a Conductor System for Investigation of proximity Effect

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Journal of Electromagnetic Analysis and Applications 2012年第11期4卷 440-446页

作者： Asha Shendge Department of Electrical and Electronics Engineering Doshisha University Kyoto Japan.

The proximity effect is very significant to investigate transient peak voltages and EMC related problems of a conductor system. In this paper, effect of energized single conductor in close proximity of an Al plate when an Al plate is used as return path is investigated to find out proximity effect. The analysis involves simulation by the Finite Time Domain Method (FDTD) in comparison with field measurements. It is observed that the current distribution is uneven in pipe conductor due to the proximity effect of varying heights from ground.

关键词： Pipe Conductor Series Impedance Shunt Admittance EMTP proximity Effect FDTD

Back to Back Combined Single Feed proximity Coupled Antenna with Dumbbell Shaped DGS

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Journal of Electromagnetic Analysis and Applications 2011年第2期3卷 43-46页

作者： Ashwini Kumar Arya Amalendu Patnaik Machavaram V. Kartikeyan 不详

Use of defected ground structure (DGS) to reduce the size of patch antenna is presented in this paper. In order to get a dipole like radiation pattern for some specific application a dumbbell shaped DGS is used in the common ground plane of back to back combined single fed proximity coupled antenna. A size reduction of about 60% is achieved. Parametric analysis has been done to see the resonance behavior of the antenna with DGS.

关键词： Defected Ground structure Microstrip Antennas proximity Coupling