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Remaining Useful Life Prediction for a Multi-stack Solid Oxide Fuel Cell System with Degradation Interactions

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1207-1214页

作者： Xiaojuan Wu Liangfei Xu Yang Huang Danan Yang Junhao wang houjun wang Xi Li School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 610054China State Key Lab of Automotive Safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijing 100084China School of Artificial Intelligencei and Automation Key Laboratory of Image Processing and Intelligent Control of Education MinistryHuazhong University of Science and TechnologyWuhan 430074China

Due to the constraints of manufacturing and materials,high-power plants cannot rely on only one solid oxide fuel cell stack.A multi-stack system is a solution for a highpower system,which consists of multiple fuel cell stacks.A short lifetime is one of the main challenges for the fuel cell before largescale commercial applications,and prognostic is an important method to improve the reliability of fuel cells.Different from the traditional prognostic approaches applied to single-stack fuel cell systems,the key problem in multi-stack prediction is how to solve the correlation of multi-stack degradation,which can directly affect the accuracy of prediction.In response to this difficulty,a standard Brownian motion is added to the traditional Wiener process to model the degradation of each stack,and then the probability density function of the remaining useful life(RUL)of each stack is calculated.Furthermore,a Copula function is adopted to reflect the dependence between life distributions,so as to obtain the remaining useful life for the whole multi-stack system.1 The simulation results show that compared with the traditional prediction model,the proposed approach has a higher prediction accuracy for multi-stack fuel cell systems.

关键词： Degradation interaction multi-stack remaining useful life(RUL) solid oxide fuel cell(SOFC)

数字示波器中FPGA间高速信号传输同步方法

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电子科技大学学报 2024年第2期53卷 219-226页

作者：高媛赵禹王厚军叶芃军委装备发展部北京100034 电子科技大学(深圳)高等研究院深圳518110

数据采集系统是数字示波器(DSO)的核心组成单元,随着示波器带宽采样率的逐步提升,单片模数转换器(ADC)+现场可编辑门控阵列(FPGA)的架构难以满足超高速以及多通道的应用场景,因此,高端示波器中数据采集系统普遍采用“主从”FPGA控制架... 详细信息

数据采集系统是数字示波器(DSO)的核心组成单元,随着示波器带宽采样率的逐步提升,单片模数转换器(ADC)+现场可编辑门控阵列(FPGA)的架构难以满足超高速以及多通道的应用场景,因此,高端示波器中数据采集系统普遍采用“主从”FPGA控制架构。在该架构下,多个FPGA之间信号的同步传输是实现采集系统的同步和精确采集的重要前提。针对多FPGA板卡之间的信号同步传输问题,提出了一种FPGA之间高速信号同步传输的方法,借助FPGA的IODELAY单元,通过测试数据训练找到最稳定的同步传输区间,实现多FPGA之间的同步传输。在自研的数字示波器上的实验表明,该方法能够有效实现FPGA之间高速信号的同步传输。

关键词：超高速数据采集系统现场可编辑门控阵列传输同步数字存储示波器

A Radio-Telemetry System for Navigation and Recording Neuronal Activity in Free-Roaming Rats

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Journal of Bionic Engineering 2012年第4期9卷 402-410页

作者： Dian Zhang Yanling Dong Megan Li houjun wang School of Automation Engineering University of Electronic Science and Technology of China Chengdu 611731 P. R. China School of Medicine Qingdao University Qingdao 266071 P R. China Shandong Eye Institute Qingdao 266071 P. R. China Zanvyl Krieger School of Arts and Sciences The Johns Hopkins University Baltimore 21218 USA

A radio-telemetry recording system is presented which is applied to stimulate specific brain areas and record neuronal ac- tivity in a free-roaming rat. The system consists of two major parts： stationary section and mobile section. The stationary section contains a laptop, a Micro Control Unit （MCU）, an FM transmitter and a receiver. The mobile section is composed of the headstage and the backpack （which includes the mainboard, FM transmitter, and receiver）, which can generate biphasic mi- crocurrent pulses and simultaneously acquire neuronal activity. Prior to performing experiments, electrodes are implanted in the Ventral Posterolateral （VPL） thalamic nucleus, primary motor area （M1） and Medial Forebrain Bundle （MFB） of the rat. The stationary section modulates commands from the laptop for stimulation and demodulates signals for neuronal activity recording. The backpack is strapped on the back of the rat and executes commands from the stationary section, acquires neuronal activity, and transmits the neuronal activity singles of the waking rat to the stationary section. All components in the proposed system are commercially available and are fabricated from Surface Mount Devices （SMD） in order to reduce the size （25 mm×15 mm ×2 mm） and weight （10 g with battery）. During actual experiments, the backpack, which is powered by a rechargeable Lithium battery （4 g）, can generate biphasic microcurrent pulse stimuli and can also record neuronal activity via the FM link with a maximum transmission rate of 1 kbps for more than one hour within a 200 m range in an open field or in a neighboring chamber. The test results show that the system is able to remotely navigate and control the rat without any prior training, and acquire neuronal activity with desirable features such as small size, low power consumption and high precision when compared with a commercial 4-channel bio-signal acquisition and processing system.

关键词： bio-robot radio-telemetry microcurrent stimulation navigation neuronal activity recording

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政府引导基金对企业风险承担的影响研究

财经论丛 2024年第3期 16-25页

作者：项后军张翔王利沙广东金融学院金融与投资学院广东广州510521 南京农业大学金融学院江苏南京210095 福建省交通运输综合保障服务中心福建福州350000

近来,政府引导基金项目的一些成功经验引起了各界的极大关注。政府引导基金设立的主要目的是为了引入更多资金,助力于中小企业创业创新及战略性新兴产业的成长与发展,而企业风险承担水平的提升则是其促进企业创新与产业升级的重要前置... 详细信息

近来,政府引导基金项目的一些成功经验引起了各界的极大关注。政府引导基金设立的主要目的是为了引入更多资金,助力于中小企业创业创新及战略性新兴产业的成长与发展,而企业风险承担水平的提升则是其促进企业创新与产业升级的重要前置环节。有鉴于此,本文选取中国A股主板和创业板、中小板企业2010—2020年的数据为样本对上述问题进行研究。结果发现:(1)总体上政府引导基金的引入显著提升了企业风险承担水平,且这一结论在进行了稳健性检验后依然成立。(2)政府引导基金对企业风险承担的影响具有明显的差异性。对大企业而言,政府引导基金对企业风险承担的正向促进作用是显著的,产生了“助强”的效果;而对中小企业来说,政府引导基金的促进作用并不明显,尚未达到“扶弱”的效果。(3)对传导机制的检验表明,政府引导基金通过缓解企业融资约束和代理问题来对企业风险承担产生正向促进作用。最后,本文还提出了相应的政策建议。

关键词：政府引导基金企业风险承担企业异质性

基于多光谱遥感技术的高邮湖菹草时空演变及原因分析

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环境监测管理与技术 2024年第3期36卷 78-82,87页

作者：王厚俊戴源陈宇洁张开源高乾白爽江苏省扬州环境监测中心江苏扬州225000 南京信息工程大学环境科学与工程学院江苏南京210044 生态环境部卫星环境应用中心北京100094

为了解高邮湖优势沉水植物菹草剧烈变化的原因及其时空演变对区域水环境的影响,利用2019—2023年长时序多光谱卫星遥感影像,结合现场和水质自动站监测,对高邮湖菹草与水质开展长期观测。结果显示,菹草的生长与水温、浊度等环境因子密切... 详细信息

为了解高邮湖优势沉水植物菹草剧烈变化的原因及其时空演变对区域水环境的影响,利用2019—2023年长时序多光谱卫星遥感影像,结合现场和水质自动站监测,对高邮湖菹草与水质开展长期观测。结果显示,菹草的生长与水温、浊度等环境因子密切相关,其在生长期对水质具有净化作用,而在衰退期则会产生大量污染物;高邮湖的菹草盖度由2020年的65.5%下降至2023年的5.9%,对区域水质、生物多样性和生态质量指数产生不利影响;菹草的消失与水位变化、藻类影响、鱼类数量及其优势种变化密切相关,高邮湖存在由草型湖泊向藻型湖泊转化的趋势。

关键词：菹草时空演变多光谱遥感环境因子浅水湖泊

A novel approach for unlabeled samples in radiation source identification

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Journal of Systems Engineering and Electronics 2022年第2期33卷 354-359页

作者： YANG Haifen ZHANG Hao wang houjun GUO Zhengyang School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Radiation source identification plays an important role in non-cooperative communication scene and numerous methods have been proposed in this field. Deep learning has gained popularity in a variety of computer vision tasks. Recently, it has also been successfully applied for radiation source identification.However, training deep neural networks for classification requires a large number of labeled samples, and in non-cooperative applications, it is unrealistic. This paper proposes a method for the unlabeled samples of unknown radiation source. It uses semi-supervised learning to detect unlabeled samples and label new samples automatically. It avoids retraining the neural network with parameter-transfer learning. The results show that compared with the traditional algorithms, the proposed algorithm can offer better accuracy.

关键词： radiation source identification deep learning semisupervised learning

Problems of Family Farms in China and Countermeasures

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Asian Agricultural Research 2014年第6期6卷 12-15页

作者： Huamei LIN houjun wang College of Economics and Trade Zhongkai University of Agriculture and Engineering

In the Communiqué of the Third Plenary Session of the 18 th Central Committee of the CPC,it proposed the tasks of accelerating the building of a new type of agricultural operation system,endowing farmers with more property rights,promoting equal exchanges of factors of production and balanced allocation of public resources between urban and rural areas,and improving the institutions and mechanisms for promoting the sound development of urbanization. However,as new agricultural operating entities,family farms have problems of land circulation,lack of scientific and technological talents,and backward infrastructure. In line with these problems,this study put forward recommendations and countermeasures,in the hope of promoting increase in farmers' income,increasing agricultural intensification and large-scale level,and realizing agricultural modernization.

关键词： Family farms New agricultural operating entities P

维氏气单胞菌弱毒株FS12001及其疫苗对异育银鲫的免疫效果

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水产学报 2024年第5期48卷 204-216页

作者：王艳娇张德锋任燕王庆王英英李莹莹潘厚军石存斌莫绪兵尹纪元中国水产科学研究院珠江水产研究所广东省水产动物免疫与绿色养殖重点实验室农业农村部渔用药物创制重点实验室上海海洋大学水产与生命学院

为探究由维氏气单胞菌(Av)弱毒株FS12001制备的疫苗免疫效果，将Av弱毒株FS12001制备活疫苗、灭活疫苗、ISA763A-灭活疫苗和蜂胶-灭活疫苗，腹腔注射免疫异育银鲫，同时设ISA763A佐剂、蜂胶佐剂及0.65%NaCl作为对照组。于免疫后1、3、5... 详细信息

为探究由维氏气单胞菌(Av)弱毒株FS12001制备的疫苗免疫效果，将Av弱毒株FS12001制备活疫苗、灭活疫苗、ISA763A-灭活疫苗和蜂胶-灭活疫苗，腹腔注射免疫异育银鲫，同时设ISA763A佐剂、蜂胶佐剂及0.65%NaCl作为对照组。于免疫后1、3、5、7和14 d经实时荧光定量PCR (qRT-PCR)检测脾脏组织中IgM、IL-1β及LZM的基因表达量；于免疫后7、14、21、28、42和48 d尾静脉采血分离血清，检测IgM抗体水平，测定SOD和LZM酶活性；于免疫28 d后用2株Av强毒株分别攻毒各组实验鱼，连续观察记录7 d，计算各免疫组的相对保护率。结果显示，各免疫组脾脏组织中IgM、IL-1β及LZM的基因表达量高于对照组，且ISA763A-灭活疫苗组和蜂胶-灭活疫苗组的表达量显著高于其他各实验组。各疫苗免疫组血清特异性抗体水平均显著高于0.65%NaCl对照组和佐剂对照组。各疫苗免疫组的LZM活性均在28 d最高，灭活疫苗组、ISA763A-灭活疫苗组及蜂胶-灭活疫苗组SOD活性均在7 d最高。菌株AVCA07攻毒后，活疫苗组、灭活疫苗组、ISA763A-灭活疫苗组和蜂胶-灭活疫苗组的RPS分别为63%、56%、100%和56%；菌株YC170511攻毒后，以上4个免疫组RPS分别为59%、55%、93%和72%。研究表明，用弱毒株FS12001制备疫苗，注射免疫异育银鲫后均可增加脾脏中IgM、IL-1β及LZM的基因表达量，提高血清抗体水平，增强SOD和LZM酶活性，增强其抵抗Av感染的能力。

关键词：异育银鲫维氏气单胞菌弱毒株疫苗免疫效果

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空间网格结构挠度检测方法

重庆建筑 2024年第4期23卷 58-60页

作者：张树勋李后军崔萌王宁国家网架及钢结构产品质量检验检测中心江苏徐州221000 江苏贝思特建设科技有限公司江苏徐州221000

挠度是空间网格结构的重要检测项目,但相关标准对于挠度检测方法的规定不够明确。该文结合工程实例对挠度检测方法中存在的问题进行了探讨,并利用结构分析软件来实现节点基准标高的计算,可为准确检测挠度提供参考。

关键词：空间网格结构网架挠度检测

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