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考虑频率特性的高压电缆在线故障测距研究
Research of On-Line Fault Location for HV Power Cable Considering Frequency Characteristic  [PDF]
张欣
Sustainable Development (SD) , 2012, DOI: 10.12677/sd.2012.21005
Abstract: 对电力电缆发生故障时产生的行波在传输过程中的色散规律进行了研究，对各模量的传播模式进行了分析，采用小波变换方法提取故障行波波头信息，探讨了依频波速的选取，并以ATP仿真软件建立110 kV交联聚乙烯绝缘电缆模型，验证了双端在线故障测距算法的准确性。
This paper analyses the dispersion rules of traveling wave produced by a short circuit fault in propagation process in a power cable and the propagation modes of every modulus, wavelet transform is used to extract traveling wave front information, and frequency-dependent wave velocity is chosen for fault lo- cation, finally a model of 110 kV XLPE cable is built by simulation tool ATP, and the accuracy of double terminal on-line fault location method is verified.
老年人负性偏向研究综述
An Overview of the Negative Bias Research of the Elderly  [PDF]
张欣
Advances in Psychology (AP) , 2022, DOI: 10.12677/AP.2022.123068
Abstract: 负性偏向是生物对负性实体的一种关注性倾向，研究表明我们对负性的事件、物体和人格特质等的注意偏好是与生俱来的。对负性实体的注意偏好使生物能快速地发觉环境中的威胁，对危险进行有效预警。从生物进化的角度来看，它是生物生存繁衍的必要条件和重要保护机制，是生物进化繁衍过程中自动化加工进行的防御机制。二十一世纪是我国老年人口数量及人口老龄化的快速增长时期，老年人口在社会总人口中的比重将逐渐增大，其中有关老年人群体的负性偏向研究也变得愈发重要。所以本文旨在总结概述有关老年人负性偏向的相关研究。
Negative bias is a biological attentional tendency towards negative entities. Studies show that we are born with an attentional preference for negative events, objects and personality traits. Attentional preference for negative entities enables organisms to quickly detect threats in the environment and effectively warn against dangers. From the perspective of biological evolution, attentional preference for negative entities is a necessary condition and an important protection mechanism for the survival and reproduction of organisms, as well as an automatic defense mechanism in the process of biological evolution and reproduction. The 21st century is a period that the number of elderly and the aging process accelerates rapidly in China. The proportion of the elderly will increase gradually. The research on the negative bias of the elderly has become more and more important. Therefore, this paper aims to summarize the relevant research on the negative bias of the elderly.
基于FPGA的无线传能数字控制系统的研究
Research on Wireless Power Transfer Digital Control System Based on FPGA  [PDF]
吴超, 张欣
Journal of Electrical Engineering (JEE) , 2019, DOI: 10.12677/JEE.2019.73019
Abstract:
文章分析了目前的无线传能控制系统的优缺点。为了解决磁耦合式无线传能系统的失谐问题，从理论上分析了系统的工作原理，提出了基于可变模全数字锁相环的频率跟踪控制方法；通过Simulink仿真分析了环路滤波器对系统响应速度和稳态误差的影响，并且通过在锁相环中增加误差量化环节提升了锁相环的锁相速度与锁相精度；最后基于FPGA设计了全数字WPT控制系统，实现了WPT系统的谐振频率自动跟踪，增加了系统过流和过温保护功能，通过仿真和制作样机进行实验，验证了本系统具有跟踪速度快，稳态误差小、安全稳定等优点。
This paper analyzes the advantages and disadvantages of current wireless energy transfer control systems. In order to solve the detuning problem of the magnetic coupling wireless power transfer system, the working principle of the system is theoretically analyzed, and a frequency tracking control method based on variable mode digital phase locked loop is proposed. The influence of the loop filter on the system response speed and steady-state error is analyzed by Simulink simulation, and the phase-locked speed and phase-locking accuracy of the phase-locked loop are improved by adding the error quantization link in the phase-locked loop. Finally, based on FPGA, the all-digital WPT control system is designed to realize the automatic tracking of the resonant frequency of WPT system, which increases the over-current and over-temperature protection functions of the system. Through simulation and prototype production, it is verified that the system has fast tracking speed and stability, the state error is small, safe and stable.
父母教养方式对中职学生主观幸福感的影响机制研究
The Effects of Parenting Style on Subjective Well-Being in Secondary Vocational Students  [PDF]
张惠欣
Advances in Psychology (AP) , 2021, DOI: 10.12677/AP.2021.1111299
Abstract: 本研究为探究父母教养方式、自我管理、领悟社会支持对中职学生主观幸福感的影响，扩展提升中职学生主观幸福感的教学方法。利用青少年自我管理能力问卷、领悟社会支持量表、主观幸福感量表、父母教养方式评价量表，以浙江省、江苏省和上海市的546名中职学生作为被试展开问卷调查，并建立以自我管理和领悟社会支持为中介的链式中介模型。研究结果如下：1) 成绩排名优秀和非单亲家庭的中职学生能够感受到更高程度的主观幸福感；2) 自我管理和领悟社会支持仅在父母教养方式中的温暖维度与主观幸福感间构成完整且显著的链式中介模型。
The purpose of this study is to explore the influence of parenting style, self-management and un-derstanding of social support on the subjective well-being of secondary vocational students, and to expand the teaching methods to improve the subjective well-being of secondary vocational students. Adolescent self-management ability questionnaire, perceived social support scale, subjective well-being scale and parenting style evaluation scale were used. A questionnaire survey was conducted among 546 secondary vocational students from Zhejiang province, Jiangsu province and Shanghai city, and a chain mediation model was established with self-management and perceived social support as mediators. The results are as follows: 1) Secondary vocational students with excellent academic performance and non-single parent families can feel higher degree of subjective well-being; 2) Self-management and perceived social support only formed a complete and significant chain mediation model between the warmth dimension of parenting style and subjective well-being.
专业提高实验对专业培养的意义——以MoSe2场效应管为例
Improving Experimental Aiming at Undergraduate Training—MoSe2 FET as an Example  [PDF]
林志萍, 张欣
Creative Education Studies (CES) , 2019, DOI: 10.12677/CES.2019.74084
Abstract:
实验以专业理论为基础，为培养本科生的创新能力和动手能力，结合当前研究热点，以“新型二维MoSe2场效应管的制备和性质”为例，说明专业提高实验。实验选题前沿、内容新颖、操作相对简单，适合本科生作为专业提高实验。实验的开展，既可以让学生从参与内容设计和结果分析方面加深本科阶段的学习，也可以学习多种高端科研仪器的使用，激发部分学生对科学研究的兴趣。
Based on theory foundation, improving experiments about the preparation and properties study of MoSe2 FET are opened to order to train their innovation and hands-on ability. Due to its frontier topic, novel content and relatively simple operation, experiments are very suitable for the professional improvement experiment. Experiments that students have been participated in design and result analysis, can promote the in-depth understanding of leaning content and can learn to use high-end scientific instruments. And it can also stimulate some students’ interest in scientific research and want to do this job.
考虑磁致伸缩效应时电机定子硅钢片的振动研究
Study on Vibration of Silicon Steel Sheet of Motor Stator Considering Magnetostrictive Effect  [PDF]
宋子晗, 张欣
Journal of Electrical Engineering (JEE) , 2021, DOI: 10.12677/JEE.2021.91001
Abstract: 为了研究交变磁场下电机定子硅钢片磁致伸缩效应的变化规律，本文首先建立了无取向硅钢片磁–机械耦合数值模型，研究了不同叠压片数无取向硅钢片在交变磁场中表面应力的变化情况，并根据仿真模型搭建了实验平台进行实验。将硅钢片水平放置在线圈一侧，并由绝缘材料固定位置，然后分别对水平放置和倾斜45？放置的无取向硅钢片进行了应变采集和振动测量实验，结果都发现在同一交变磁场下，随着无取向硅钢片叠压片数的增加，无取向硅钢片表面的应变和振动情况逐渐减小，这与仿真结果相符。此结论对电机减振降噪有一定的指导意义。
In order to study the variation law of magnetostrictive effect of motor stator silicon steel sheet under alternating magnetic field, the magnetic mechanical coupling numerical model of non oriented silicon steel sheet is established in this paper, and the change of surface stress of non oriented silicon steel sheet with different number of laminated sheets in alternating magnetic field is studied, and the experimental platform is built based on the simulation model. The non- oriented silicon steel sheet was placed horizontally on one side of the coil and fixed by insulating material. Then the strain collection and vibration measurement experiments were carried out on the non oriented silicon steel sheet placed horizontally and inclined 45？ respectively. The results show that, under the same alternating magnetic field, the strain and vibration on the surface of the non oriented silicon steel sheet gradually decrease with the increase of the number of laminated sheets The true result is consistent. This conclusion has a certain guiding significance for motor vibration and noise reduction.
抑郁症个体奖赏敏感性异常及情绪失调的生物标记物
Biomarkers of Anhedonia and Mood Disorders in Depressed Individuals  [PDF]
张欣, 王恩国
Advances in Psychology (AP) , 2021, DOI: 10.12677/AP.2021.116158
Abstract: 抑郁症是一种常见的复发性心境障碍，是当今世界范围内最常见的精神疾病之一。快感缺乏与情绪失调均是抑郁症的核心特征，反馈相关负波和晚期正成分分别为其生物标记物，根据目前的研究，反馈相关负波异常和晚期正成分异常与抑郁症之间存在关联，可以作为抑郁发作及抑郁症状程度加重的预测因素，对于早期诊断也有着重要意义。对大量的研究进行梳理之后发现，目前还存在着抑郁被试的筛选标准存在差异、反馈相关负波的来源、功能以及取值标准尚未统一的问题，并且，抑郁症的异质性对反馈相关负波以及晚期正成分是否有影响目前尚没有相关研究得出结论，在未来的研究中值得进一步深入探讨。
Depression is a common recurrent mood disorder and one of the most common mental diseases in the world today. Anhedonia and mood disorders are the core characteristics of depression. Feedback-related negative and late positive component are the biomarkers, respectively. According to the current study, feedback-related negative abnormality and late positive component abnormality are associated with depression, which can be used as a predictor of depressive episode and aggravation of depressive symptoms, and is of great significance for early diagnosis. After sorting out a large number of studies, it is found that there are still differences in the screening criteria of depression subjects, and the source, function and value criteria of feedback-related negative have not been unified. In addition, whether the heterogeneity of depression has an effect on the feedback-related negative and the late positive component has not been concluded by relevant studies at present, which is worthy of further discussion in future studies.
近20年学习困难的认知加工机制研究
Research on Cognitive Processing Mechanism of Learning Difficulty in Recent 20 Years  [PDF]
张欣, 王恩国
Advances in Psychology (AP) , 2021, DOI: 10.12677/AP.2021.116162
Abstract: 随着社会的不断发展，学习困难现象日益被重视，不仅是心理学、教育学、医学研究的重点领域，并且逐渐成为一个综合性的社会问题。通过对近20年学习困难的认知加工机制研究进行梳理后发现，工作记忆对造成学习困难原因的解释量最大，而工作记忆缺陷是由于短时记忆、长时记忆信息提取、抑制机制的不足或它们之间的相互结合造成的。今后研究可以采用新的视角，拓宽研究领域与范围、改进研究方法。
With the continuous development of society, the phenomenon of learning difficulties has been paid more and more attention. It is not only a key field of psychology, education and medical re-search, but also a comprehensive social problem gradually. After sorting out the cognitive processing mechanism of learning difficulties in the past 20 years, it is found that, working memory is the most likely explanation for learning difficulties, the defects of working memory are caused by short-term memory, long-term memory information extraction and inhibition mechanism or their combination. In the future, a new perspective can be adopted to broaden the research field and scope and improve the research methods.
共创GIS领域新天地——华胜公司成为澳大利亚GENASYS公司中国区独家总代理
张欣
中国图象图形学报 , 1997,
Abstract: 共创ＧＩＳ领域新天地——华胜公司成为澳大利亚ＧＥＮＡＳＹＳ公司中国区独家总代理日前，全球ＧＩＳ领域最大的公司之一澳大利亚ＧＥＮＡＳＹＳ公司与北京华胜计算机有限公司在北京国际会议中心共同举办了中国区独家总代理授权仪式暨’９７ＧｅｎａＭａｐ用户大会。电子...
软木家具设计研究
张欣
包装工程 , 2013,
Abstract: 以生态设计趋势下软木材料的广泛应用为启示，分析了软木及其家具的界定、制程和材料工艺，并指出上述经验启示与材料试验、原型制作间的联结转化。在此基础上，提出此类设计的2 种重要方式：一是木材性能的合理利用；二是材料效率的有效探索。进而结合我国实际及原料生命周期理论，提出了材料驱动生态家具设计的几条可行建议。
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