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海水淡化高压泵与能量回收一体机水润滑轴承-转子系统稳定性

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排灌机械工程学报 2024年第1期42卷 21-29页

作者：潘文翊李岩张德胜敬睿胡敬宁叶晓琰江苏大学国家水泵及系统工程技术研究中心江苏镇江212013

为保障海水淡化高压泵与能量回收一体机的安全稳定运行,对轴颈倾斜时的水润滑转子系统的稳定性展开研究.基于流体动压润滑理论,采用差分法和微扰法,建立考虑四自由度的32动力系数模型,同时求解转子动力学方程,分析不同偏心距、倾斜角、... 详细信息

为保障海水淡化高压泵与能量回收一体机的安全稳定运行,对轴颈倾斜时的水润滑转子系统的稳定性展开研究.基于流体动压润滑理论,采用差分法和微扰法,建立考虑四自由度的32动力系数模型,同时求解转子动力学方程,分析不同偏心距、倾斜角、载荷下轴承的动静特性和口环间隙水膜产生的流体动压润滑效应对转子稳定性的影响.求解转子系统特征方程,并通过特征值实部对转子的稳定性进行分析.研究结果表明:倾斜运动对转子稳定性影响较大,四自由度下偏心率和倾斜角的增大使得32个动特性系数有不同程度的增大,从而减小运行过程中转子涡动产生的位移量,同时具有更高的承载能力;口环间隙水膜的动压润滑效应对转子稳定性具有不可忽视的影响,可使得转子的位移响应减小为原来的1/3,达到稳定运行的时间缩短为原来的1/3;一体机转子的极限转速为40000~45000 r/min,当转速超过极限转速时,系统出现正实部的特征值,增大口环宽度和减小口环水膜间隙厚度可增大转子的极限转速.

关键词：水润滑转子四自由度动静特性稳定性轴心轨迹

产教融合视角下地方高校数字媒体艺术设计人才培养路径探析

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设计 2024年第1期37卷 94-96页

作者：李妍齐靖宁张旭保定学院美术与设计学院河北省社会科学院

当前,地方高校数字媒体艺术专业产教融合培养实践在广度和深度上尚存在不足,通过培养产教融合主体间利益共同体、共建课程体系和人才培养方案、建设以成果为导向的教学内容、依托地方资源共建协同育人平台、校企共同培养师资队伍等举措... 详细信息

当前,地方高校数字媒体艺术专业产教融合培养实践在广度和深度上尚存在不足,通过培养产教融合主体间利益共同体、共建课程体系和人才培养方案、建设以成果为导向的教学内容、依托地方资源共建协同育人平台、校企共同培养师资队伍等举措,推进地方高校数字媒体艺术设计专业产教融合发展。未来,在服务时长、服务产业、人才培养格局等方面,要着力培养数字媒体艺术应用型人才,满足新时代发展对数字媒体艺术人才的需求,以推进地方高校数字媒体艺术专业应用转型,更好地承担区域经济社会发展的责任。

关键词：产教融合地方高校数字媒体艺术设计人才培养校企合作

Cost reduction of a hybrid energy storage system considering correlation between wind and PV power

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Protection and Control of Modern Power Systems 2016年第1期1卷 86-94页

作者： Lin Feng jingning zhang Guojie Li Bangling zhang School of Electrical Information and Electronic Engineering Shanghai Jiao Tong UniversityShanghaiChina Shanghai Power&Energy Storage Battery System Engineering Tech.Co.Ltd. ShanghaiChina.

A hybrid energy storage system(HESS)plays an important role in balancing the cost with the performance in terms of stabilizing the fluctuant power of wind farms and photovoltaic(PV)stations.To further bring down the cost and actually implement the dispatchability of wind/PV plants,there is a need to penetrate into the major factors that contribute to the cost of the any HESS.This paper first discusses hybrid energy storage systems,as well as chemical properties in different medium,deeming the ramp rate as one of the determinants that must be observed in the cost calculation.Then,a mathematical tool,Copula,is explained in details for the purpose of unscrambling the dependences between the power of wind and PV plants.To lower the cost,the basic rule for allocation of buffered power is also put forward,with the minimum energy capacities of the battery ESS(BESS)and the supercapacitor ESS(SC-ESS)simultaneously determined by integration.And the paper introduces the probability method to analyze how power and energy is compensated in certain confidence level.After that,two definitions of coefficients are set up,separately describing energy storage status and wind curtailment level.Finally,the paper gives a numerical example stemmed from real data acquired in wind farms and PV stations in Belgium.The conclusion presents that the cost of a hybrid energy storage system is greatly affected by ramp-rate and dependence between the power of wind farms and photovoltaic stations,in which dependence can easily be determined by Copulas.

关键词： Probability analysis Copula Correlation Capacity optimization Hybrid ESS

Characterizing noise correlation and enhancing coherence via qubit motion

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Fundamental Research 2021年第1期1卷 10-15页

作者： Jiaxiu Han Zhiyuan Li jingning zhang Huikai Xu Kehuan Linghu Yongchao Li Chengyao Li Mo Chen Zhen Yang Junhua Wang Teng Ma Guangming Xue Yirong Jin Haifeng Yu Beijing Academy of Quantum Information Sciences Beijing 100193China

The identification of spacial noise correlation is of critical importance in developing error-corrected quantum devices,but it has barely been studied so far.In this work,we utilize an effective method called qubit motion,to efficiently determine the noise correlations between any pair of qubits in a 7-qubit superconducting quantum system.The noise correlations between the same pairs of qubits are also investigated when the qubits are at distinct operating frequencies.What’s more,in this multi-qubit system with the presence of noise correlations,we demonstrate the enhancing effect of qubit motion on the coherence of logic qubits,and we propose a Motion-CPMG operation sequence to more efficiently protect the logic state from decoherence,which is experimentally demonstrated to extend the coherence time of logic qubits by nearly one order of magnitude.

关键词： Qubit motion Noise correlation Decoherence CPMG Quantum error correction

面向曲面应变监测的SAW应变传感单元的设计

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机电工程技术 2024年第1期53卷 91-94页

作者：陈睿张勇斌肖鸿洋王君杨徐静宁中国工程物理研究院机械制造工艺研究所四川绵阳621000

高端装备的内部性能参数,如应变等的实时监测,对评估装备在各状态、各阶段的性能变化尤为重要。基于高端装备的应变无源无线监测需求,根据待测表面的曲面特性,设计了面向曲面应变传感的SAW传感芯片,并通过有限元方法对设计参数进行了仿... 详细信息

高端装备的内部性能参数,如应变等的实时监测,对评估装备在各状态、各阶段的性能变化尤为重要。基于高端装备的应变无源无线监测需求,根据待测表面的曲面特性,设计了面向曲面应变传感的SAW传感芯片,并通过有限元方法对设计参数进行了仿真分析和优化设计,采用特殊结构设计以增加曲面应变监测效果及提升应变芯片灵敏度。采用MEMS加工方法制作了应变芯片样品,并使用矢量网络分析仪测量了芯片的工作频率。测试结果表明,所设计的应变传感芯片中心频率与仿真结果接近。最后搭建应变测试平台进行实验研究,结果表明,所设计的应变芯片灵敏度达到1500 Hz/με,并且在模拟曲面构建应用场景的实验装置中表现出良好的适用性,上述研究为SAW器件在曲面构件应变监测上的应用提供了参考。

关键词：声表面波应变传感曲面应变 MEMS技术谐振频率

Critical survival barrier for branching random walk

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Frontiers of Mathematics in China 2019年第6期14卷 1259-1280页

作者： jingning LIU Mei zhang School of Mathematical Sciences Chongqing Normal UniversityChongqing 400047China School of Mathematical Sciences Laboratory of Mathematics and Complex SystemsBeijing Normal UniversityBeijing 100875China

We consider a branching random walk with an absorbing barrier,where the associated one-dimensional random walk is in the domain of attraction of an a-stable law.We shall prove that there is a barrier and a critical value such that the process dies under the critical barrier,and survives above it.This generalizes previous result in the case that the associated random walk has finite variance.

关键词： Branching random walk cv-stable spine absorption critical barrier

Gastric vagal afferent inputs reach the glycemia-sensitive neurons of lateral hypothalamic area in the rat

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Chinese Science Bulletin 2003年第6期48卷 577-581页

作者： zhang Yueping ZHU jingning JIANG Jianming WANG Jianjun Department of Biological Science and Technology Nanjing UniversityNanjing 210093China

The glycemia-sensitive neuron in lateral hypothalamic area (LHA) is one of the important central neural events involved in the feeding control. Electrophysio-logical studies have demonstrated that gastrointestinal vagal afferent inputs could convey the meal-related information of gastrointestinal tract to the hypothalamus. In this study, we examined whether the gastric vagal afferent inputs could reach the glycemia-sensitive neurons of the LHA by using in vivo extracellular recording technique in the rat. The results showed that stimulation of gastric vagal nerves elicited two types of the LHA neurons responses: the phasic response (93/116, 80.2%) and the change in cells firing pattern (23/116, 19.8%). Within the 93 cells that responded to the gastric vagal stimulation with a phasic response, 67 (72.0%) showed an inhibition in the cells firing rate, 26 (27.4%) were excited. Of the 23 cells that showed a change in the firing pattern, 13 responded to the gastric vagal stimulation with a long-lasting increase or decrease in firing rate, the remaining 10 cells turned their discrete spiking to the burst discharging. In addition, of 101 LHA neurons including the two types of responsive neurons, 73 (72.3%) were identified to be glyce-mia-sensitive neurons. These results demonstrated that the gastric vagal afferent inputs could reach the LHA and pre-dominantly reach those glycemia-sensitive neurons in the LHA. Presumably, the modulation of glycemia-sensitive neurons of LHA by the gastric vagal afferent inputs may play an important role in the short-term regulation of feed-ing behavior.

关键词：大鼠下丘脑外侧区胃迷走神经传入纤维摄食调节血糖感受神经元

Influence of Magnet Shape on the Cogging Torque of a Surface-mounted Permanent Magnet Motor

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Chinese Journal of Electrical Engineering 2019年第4期5卷 40-50页

作者： Min Zhou Xinxing zhang Wenxiang Zhao Jinghua Ji jingning Hu Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China Jingjiang College Jiangsu UniversityZhenjiang 212013China

The influence of bread-loaf shaped magnet poles under parallel magnetization on the cogging torque of surface-mounted permanent magnet(SPM)motors is studied.For the SPM motors having magnetic poles with eccentricity and sine harmonic compensation,the electromagnetic performances of integer and fractional slot motors are compared.It is found that the cogging torque and torque ripple of the integer and fractional slot motors can be reduced with the same eccentric magnet pole.The cogging torque and torque ripple of a fractional slot motor can be decreased by sine harmonic compensation,however,the same sine harmonic compensation has a small influence in integer slot motors.By varying the magnetic poles,the contribution of the field harmonics(k=(2n+1)p),which are a direct result of magnet magnetization,to the cogging torque also changes.The electromagnetic performance of a 3 kW prototype is tested,and it is found that the experimental results validate the theoretical investigation.

关键词： Analytical model bread-loaf magnet shape finite-element(FE) cogging torque surface-mounted permanent magnet(SPM)motor

Excitatory effect of histamine on neuronal activity of rat cerebellar fastigial nucleus in vitro

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Chinese Science Bulletin 2007年第4期52卷 497-503页

作者： TANG Biao zhang Jun LI HongZhao ZHU jingning WANG JianJun Department of Biological Science and Technology/State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing 210093 China Jiangsu Key Laboratory for Bioresource Technology School of Life Sciences Nanjing Normal University Nanjing 210097 China

The cerebellar fastigial nucleus (FN) holds an important role in motor control and body balance. Previous studies have revealed that the nucleus is innervated by direct hypothalamocerebellar histaminergic fibers. However, the functional role of histaminergic projection in cerebellar FN has never been established. In this study, we investigated the effect of histamine on neuronal firing of cerebellar FN by using slice preparations. Sixty-five FN cells were recorded from 47 cerebellar slices, and a vast majority of the cells responded to histamine stimulation with an excitatory response (58/65, 89.2%). Perfusing slices with low-Ca2+/high-Mg2+ medium did not block the histamine-induced excitation (n=10), supporting a direct postsynaptic action of histamine on the cells. Furthermore, the excitatory effect of histamine on FN neurons was not blocked by selective histamine H1 receptor antagonist triprolidine (n=15) or chlorpheniramine (n=10), but was effectively suppressed by ranitidine (n=15), a highly selective histamine H2 receptor antagonist. On the other hand, highly selective histamine H2 receptor agonist dimaprit (n=20) instead of histamine H1 receptor agonist 2-pyridylethylamine (n=16) mimicked the ex- citatory effect of histamine on FN neurons. The dimaprit-induced FN neuronal excitation was effectively antagonized by selective histamine H2 receptor antagonist ranitidine (n=13) but not influenced by se- lective histamine H1 receptor antagonist triprolidine (n=15). These results demonstrate that histamine excites cerebellar FN cells via the histamine H2 receptor mechanism and suggest that the hypotha- lamocerebellar histaminergic fibers may modulate cerebellar FN-mediated sensorimotor integration through their excitatory innervations on FN neurons.

关键词：大鼠小脑顶核神经活动组胺受体兴奋作用