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Advance of Study on Design Methods of Hydraulic System of Radio Remote Control of Construction Machinery

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Journal of Northeast Agricultural University(English Edition) 2003年第2期10卷 156-160页

作者： FENG kai-lin,yang wei-min,CHEN kang-ning(Xi’an Jiaotong University,Xi’an,710049,PRC) Xi'an Jiaotong University Xi'an710049PRC

The working principle of radio remote controlling of construction machinery should be that signals of the radio wave from the transmitter obtained in the receiver were controlled and then changed into electronic analog or digital signals which can be used to drive different actuators and mechanisms of the *** vehicle could be acted by following the controlling instructions sent by the *** best operation mode of construction machinery is suitable not only to manual operating but also to remote controlling in the same *** design methods of the hydraulic system used for the radio remote controlling of construction machinery are *** design methods of hydraulic circuits for the actuators controlled by solenoid on-off type valves,hydro-electronic multi-way proportional valves,closed loop proportional servo driver or three-way proportional reducing valves are discussed in detail (with real example).The design methods of the power shift transmission of electro-hydraulic controlling,the devices of braking and the directional streering are discussed in this paper.

关键词： radio remote controlling construction machinery proportional controlling three-way proportional pressure reducing control

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou kai Tao Mengyang Li Bing wei Hongjing Wu Mengyang Li Bing wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

A denoising algorithm based on the improved EWT in distributed fiber optic temperature measurement system

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Optoelectronics Letters 2025年

作者： Xu Xiaoyi Hu kai wei Xiaoying Zhang kailiang Tianjin University of Technology， School of Integrated Circuit Science and Engineering Aerospace Optoelectronic Technology Development Co.， Ltd.

In order to enhance the temperature measurement accuracy of Raman distributed fiber optic temperature measurement system， in this paper， we propose a distributed fiber optic temperature measurement signal denoising algorithm based on the empirical wavelet transform with improved thresholding. This algorithm is used to decompose the noisy signal into multiple intrinsic modal threshold functions， which are further reconstructed by correlation filtering and threshold processing each of the IMFs using an improved function. The correlation filtering mechanism in this algorithm effectively reduces the regular noise and the amount of computation to improve the response speed. The improved threshold function can significantly reduce the spiky noise and smoothen the signal. The field temperature data is collected in the experiment， and the algorithm is implemented in the FPGA platform. In measured results， the system's temperature measurement accuracy is ±0.18℃ over 2.5 km of sensing fiber， with average response time is 0.6 seconds.

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Spin-dependent transport characteristics of nanostructures based on armchair arsenene nanoribbons

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Chinese Physics B 2017年第9期26卷 542-548页

作者：杨开巍李明君张小姣李新梅高永立龙孟秋 Hunan Key laboratory of Super Micro-structure and Ultrafast Process School of Physics and ElectronicsCentral Soulh UniversityChangsha 410083China Physical Science and Technology College of Yichun University Yichun 336000China Department of Physics and Astronomy University of RochesterRochesterNY 14627USA

By employing non-equilibrium Green＇s function combined with the spin-polarized density-functional theory, we investigate the spin-dependent electronic transport properties of armchair arsenene nanoribbons（a As NRs）. Our results show that the spin-metal and spin-semiconductor properties can be observed in a As NRs with different widths. We also find that there is nearly 100% bipolar spin-filtering behavior in the a As NR-based device with antiparallel spin configuration. Moreover, rectifying behavior and giant magnetoresistance are found in the device. The corresponding physical analyses have been given.

关键词： armchair arsenene nanoribbons spin-dependent electronic transport property spin-polarized density-functional theory bipolar spin-filtering behavior

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知识计量学20年

信息与管理研究 2020年第4期5卷 57-65页

作者：宋艳辉魏开洋杭州电子科技大学中国科教评价研究院浙江杭州310018 杭州电子科技大学管理学院浙江杭州310018

随着科学技术和社会经济的飞速发展,知识化逐渐被社会各个领域所熟知,人们对知识的认知进一步加强,尤其是知识经济与知识管理在全球范围内都普遍兴起,知识作为一种战略资源和经济资源,目前已经成为当前科学技术、经济与社会发展的重要... 详细信息

随着科学技术和社会经济的飞速发展,知识化逐渐被社会各个领域所熟知,人们对知识的认知进一步加强,尤其是知识经济与知识管理在全球范围内都普遍兴起,知识作为一种战略资源和经济资源,目前已经成为当前科学技术、经济与社会发展的重要因素和显著特征。尽管各个学科都对知识从不同的角度和层次进行了分析和研究,取得了一定的研究成果,但是关于知识本身及其影响的测度、计量等重要研究领域仍处于不够完善的状态,研究究进度不为大部分学者所了解,使得该领域的研究内容不够系统、清晰,使得部分学者不能够更加充分地了解这一领域。为此文章针对知识计量学领域展开研究,应用可视化软件对该领域进行分析,对当前该领域的国内外发展状况、主题、同“五计学”究关系以及应用进行了梳理,以期展示知识计量学究发展全貌。

关键词：知识计量学 “五计学” 知识图谱

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氢化脱氨基反应的研究进展

昆明理工大学学报（自然科学版） 2017年第5期42卷 90-104页

作者：高凯张伟杨波廖霞俐昆明理工大学生命科学与技术学院云南昆明650500

氢化脱氨基反应是分子中氨基被氢取代的反应,是有机合成中一种重要的官能团转化形式.最常见的氢化脱氨基反应是经由重氮盐的氢化去重氮化反应,可由醇类、次磷酸/次磷酸盐等提供氢源,主要的反应机理为自由基机理.此外还包括一些不经由重... 详细信息

氢化脱氨基反应是分子中氨基被氢取代的反应,是有机合成中一种重要的官能团转化形式.最常见的氢化脱氨基反应是经由重氮盐的氢化去重氮化反应,可由醇类、次磷酸/次磷酸盐等提供氢源,主要的反应机理为自由基机理.此外还包括一些不经由重氮盐的氢化脱氨基反应,如先合成磺酰肼/磺酰胺或铵盐等再进行氢化脱氨基等.目前氢化脱氨基反应的底物主要集中在芳香伯胺,而脂肪族底物的例子较少.本文首次对这一重要领域进行了综述,主要总结了氢化脱氨基反应几种主要的反应类型,讨论了主要的反应机理,并列举了该反应的若干重要应用.

关键词：伯胺氢化脱氨基重氮盐氢源自由基机理

利用MIVM模型预测冶金级硅真空精炼过程杂质的挥发特性

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真空科学与技术学报 2016年第10期36卷 1193-1199页

作者：于强伍继君马文会刘凯魏奎先杨斌戴永年昆明理工大学云南省有色金属真空冶金重点实验室昆明650093 昆明理工大学云南省高校硅冶金与硅材料工程研究中心昆明650093 昆明理工大学复杂有色金属资源清洁利用国家重点实验室昆明650093

运用分子相互作用体积模型预测了二元硅基熔体中Zn、Sb、Mg、Mn、Cu和Sn的活度系数.结合模型所得的对势能相互作用B参数和活度等热力学数据,计算了硅与各杂质元素形成的二元系蒸发系数和挥发速率,绘制出了硅基合金蒸馏过程中的气液相平... 详细信息

运用分子相互作用体积模型预测了二元硅基熔体中Zn、Sb、Mg、Mn、Cu和Sn的活度系数.结合模型所得的对势能相互作用B参数和活度等热力学数据,计算了硅与各杂质元素形成的二元系蒸发系数和挥发速率,绘制出了硅基合金蒸馏过程中的气液相平衡图。研究结果表明,模型所预测的活度值与实验值吻合很好,真空精炼有利于Sb、Zn、Mg从硅熔体中分离,而Mn、Cu、Sn难以分离。硅中的各杂质的蒸发行为受其活度和温度的联合控制。本文通过对冶金硅中杂质挥发性质的研究,为真空提纯冶金级硅提供了可靠的理论依据。

关键词：分子相互作用体积模型冶金级硅真空蒸馏气液相平衡

Cauda equina syndrome with urinary retention as a postoperative complication of lumbar spine surgery:A case report

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World Journal of Clinical Cases 2025年第10期13卷 40-45页

作者： kai-Wu yang wei-Hong Lai Da-wei Huang Department of Urology Chiayi Christian HospitalChiayi 600566Taiwan Department of Neurosurgery Chiayi Christian HospitalChiayi 600566Taiwan

BACKGROUND Cauda equina syndrome(CES)is characterized by a group of symptoms that may be caused by inflammation,spinal cord compression,venous congestion,or *** syndrome is commonly an indication for surgical intervention but has not been determined as a postoperative complication following surgery for lumbar spine *** SUMMARY To report the case of a 54-year-old male patient who had CES following spinal surgery,with no obvious compression lesions found during re-exploration,suggesting that vascular insufficiency may have contributed to the ***,a series of urodynamic studies on bladder recovery patterns in such complications have also been *** Postoperative CES requires urgent imaging and exploration to rule out compression;noncompressive cases,including vascular insufficiency may performed conservative management.

关键词： Cauda equina syndrome Lumbar spine surgery Urinary retention Urodynamic study Postoperative complication Case report

Direction of arrival estimation on cylindrical conformal array using RARE

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Journal of Systems Engineering and Electronics 2011年第5期22卷 767-772页

作者： kai yang Zhiqin Zhao wei yang Zaiping Nie School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 E R. China

When the information of mutual coupling and shadowing effect of a conformal antenna array are unknown, the performance of direction of arrival （DOA） estimation will be seriously degraded by using some classical methods, such as the multiple signal classification （MUSIC） algorithm. Meanwhile it is difficult to measure or estimate the shadowing effect. The DOA estimation for a conformal uniform circular array （UCA） is studied. Firstly, the azimuthal angle is separated from all the unknown information by transforming the UCA from the element space to the mode space. Then the rank reduction （RARE） algorithm is applied in the estima- tion of the azimuthal angle. The π ambiguity existed in the RARE is solved by the beam forming. The main advantage of this method is that it does not need to measure the mutual coupling and the shadowing effect. Compared with the subarray method, it will not decrease the aperture of the array. Simulation results validate the advantages of the method.

关键词： conformal antenna direction of arrival mutual coupling.