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造孔剂对陶瓷结合剂CBN砂轮组织结构及性能的影响

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陶瓷学报 2024年第2期45卷 338-344页

作者：王志起苗卫朋刘宾杨威孙鹏辉穆龙阁李鹤南王传运郑州磨料磨具磨削研究所有限公司河南郑州450001 高性能工具全国重点实验室河南郑州450001

为研究不同造孔剂对陶瓷结合剂CBN砂轮组织结构及性能的影响,在一定条件下,制备添加不同造孔剂的陶瓷结合剂CBN砂轮试样,对其进行抗折强度、抗冲击强度和气孔率的分析,并对其进行磨削实验。结果表明:同等条件下,添加玻璃空心球的CBN试... 详细信息

为研究不同造孔剂对陶瓷结合剂CBN砂轮组织结构及性能的影响,在一定条件下,制备添加不同造孔剂的陶瓷结合剂CBN砂轮试样,对其进行抗折强度、抗冲击强度和气孔率的分析,并对其进行磨削实验。结果表明:同等条件下,添加玻璃空心球的CBN试条气孔率最高,抗折强度和抗冲击强度下降程度较小,兼顾了强度和锋利性的两方面要求;通过磨削实验得到,当加入体积分数约20%的玻璃空心球时,砂轮磨削时的功率最小,同时能得到粗糙度低、表面质量优异的工件。

关键词：造孔剂陶瓷结合剂外圆磨 CBN砂轮

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Arc Grounding Fault Identification Using Integrated Characteristics in the Power Grid

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Energy Engineering 2024年第7期121卷 1883-1901页

作者： penghui Liu Yaning Zhang Yuxing Dai Yanzhou sun School of Electrical Engineering and Automation Henan Polytechnic UniversityJiaozuo454003China Research and Development Center Guangdong Zhicheng Champion Group Co.Ltd.Dongguan523000China Henan Key Laboratory of Intelligent Detection and Control of Coal Mine Equipment Henan Polytechnic UniversityJiaozuo454003China

Arc grounding faults occur frequently in the power grid with small resistance grounding neutral *** existing arc fault identification technology only uses the fault line signal characteristics to set the identification index,which leads to detection failure when the arc zero-off characteristic is *** solve this problem,this paper presents an arc fault identification method by utilizing integrated signal characteristics of both the fault line and sound ***,the waveform characteristics of the fault line and sound lines under an arc grounding fault are *** that,the convex hull,gradient product,and correlation coefficient index are used as the basic characteristic parameters to establish fault identification ***,the logistic regression algorithm is employed to deal with the reference samples,establish the machine discrimination model,and realize the discrimination of fault ***,simulation test results and experimental results verify the accuracy of the proposed *** comparison analysis shows that the proposed method has higher recognition accuracy,especially when the arc dissipation power is smaller than 2×10^(3) W,the zero-off period is not *** conclusion,the proposed method expands the arc fault identification theory.

关键词： Arc fault convex hull algorithm correlation coefficient fault identification gradient logistic regression

Non-affine parameter dependent LPV model and LMI based adaptive control for turbofan engines

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Chinese Journal of Aeronautics 2019年第3期32卷 585-594页

作者： Bei YANG Xi WANG penghui sun School of Energy and Power Engineering Beihang University School of Aircraft Engineering Nanchang Hangkong University

The precise control of turbofan engines thrust is an important guarantee for an aircraft to obtain good flight performance and a challenge due to complex nonlinear dynamics of engines and time-varying parameters. The main difficulties lie in the following two aspects. Firstly, it is hard to obtain an accurate kinetic model for the turbofan engine. Secondly, some model parameters often change in different flight conditions and states and even fluctuate sharply in some cases. These variable parameters bring huge challenge for the turbofan engine control. To solve the turbofan engine control problem, this paper presents a non-affine parameter-dependent Linear Parameter Varying(LPV) model-based adaptive control approach. In this approach, polynomial-based LPV modeling method is firstly employed to obtain the basis matrices, and then the Radial Basis Function Neural Networks(RBFNN) is introduced for the online estimation of the non-affine model parameters to improve the simulation performance. LPV model-based Linear Matrix Inequality(LMI) control method is applied to derive the control law. A robust control term is introduced to fix the estimation error of the nonlinear time-varying model parameters for better control performance. Finally, the Lyapunov stability analysis is performed to ensure the asymptotical convergence of the closed loop system. The simulation results show that the states of the engine can change smoothly and the thrust of the engine can accurately follow the desired trajectory, indicating that the proposed control approach is effective. The contribution of this work lies in the combination of linear system control and nonlinear system control methods to design an effective controller for the turbofan engine and to provide a new way for turbofan engine control research.

关键词： Adaptive control Linear matrix inequalities Linear parameter varying Neural networks Turbofan engines

Model reference adaptive control with smooth switching scheme for piecewise linear systems and its application in turbofan engine control

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航空动力学报 2019年第7期34卷 1615-1623页

作者： sun penghui WANG Xi YANG Bei ZENG Detang School of Energy and Power Engineering Beijing University of Aeronautics and AstronauticsBeijing100191China School of Aircraft Engineering Nanchang Hangkong UniversityNanchang330063China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China

A model reference adaptive control(MRAC)with smooth switching scheme was proposed for piecewise linear systems,and the method was utilized in turbofan engine control to avoid the discontinuity of control *** this scheme,each sub-region of the operating envelope had its own MRAC controller,and smooth indicator function based smooth switching scheme was introduced to switch multiple controllers smoothly at the boundary of adjacent *** Lyapunov stability analysis indicated that the proposed smooth switching scheme can guarantee the convergence of the closed-loop system during the controllers *** tracking error system was converted into a switched system to analyze the global stability of the closed-loop *** advantage of the method was that the chattering of system output and instability caused by asynchronous switching can be *** simulation illustrates the effectiveness of the proposed control scheme in comparison with the existing MRAC controller with gain scheduling for turbofan engine.

关键词： model reference adaptive control turbofan engine smooth switching Lyapunov function dwell time Lyapunov stability

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改进暗通道窗口与透射率修正的图像去雾

电光与控制 2022年第11期29卷 55-60,124页

作者：林森孙彭辉沈阳理工大学自动化与电气工程学院沈阳110000

雾霾天气下,航拍设备无法准确获取图像信息,为解决此问题,提出一种改进暗通道窗口与透射率修正的图像去雾算法。首先,用超像素分割有雾图像得到景深一致的局部窗口,在每个窗口内计算暗通道,同时根据大气光特性结合超像素进行大气光估计... 详细信息

雾霾天气下,航拍设备无法准确获取图像信息,为解决此问题,提出一种改进暗通道窗口与透射率修正的图像去雾算法。首先,用超像素分割有雾图像得到景深一致的局部窗口,在每个窗口内计算暗通道,同时根据大气光特性结合超像素进行大气光估计;然后,通过引导滤波细化透射率,并建立自适应容差机制来修正图像明亮区域的透射率;最后,反演大气散射模型还原清晰图像。实验结果证明,该算法所得结果图像细节清晰、颜色自然,且能处理多类雾天图像,鲁棒性更好,与经典算法相比具有显著优势。

关键词：图像去雾暗通道先验超像素分割自适应容差透射率修正

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In vivo effects of neomycin sulfate on non-specific immunity,oxidative damage and replication of cyprinid herpesvirus 2 in crucian carp(Carassius auratus gibelio)

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Aquaculture and Fisheries 2019年第2期4卷 67-73页

作者： penghui sun Fei Yu Jianfei Lu Minli Zhang Hao Wang Dan Xu Liqun Lu National Pathogen Collection Center for Aquatic Animals Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Agriculture Ministry for Freshwater Aquatic Genetic Resources Shanghai Ocean UniversityShanghai 201306China

Neomycin belongs to the family of 2-deoxystreptamine-containing aminoglycoside *** is widely used for bacterial infections,targeting most gram-negative and some gram-positive *** has also been reported to show antiviral ***,we evaluated the toxicity of neomycin sulfate,and investigated its effect on non-specific immunity and viral infection in crucian carp(Carassius auratus gibelio).The safe concentration of neomycin sulfate for crucian carp was determined to be 102.9 mg/kg in *** oxidative damage assays,neomycin sulfate increased superoxide dismutase and catalase activity and decreased malondialdehyde in the liver of crucian *** non-specific blood immune assays,the white blood cell count and complement 3 content significantly increased after neomycin sulfate treatment,while no significant changes were observed in antibacterial or lysozyme *** a challenge test,neomycin sulfate protected the crucian carp from cyprinid herpesvirus 2(CyHV-2)infection and inhibited CyHV-2 *** cytotoxicity assays,low concentrations of neomycin sulfate had no cytotoxicity on cells from the fins of crucian *** results of the present study indicate that oral administration of neomycin sulfate reduced oxidative damage,enhanced immunity and provided protection against CyHV-2 in crucian carp.

关键词： Neomycin sulfate Non-specific immunity Oxidative damage Crucian carp Cyprinid herpesvirus 2

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背板对聚甲基丙烯酸甲酯向下火蔓延的影响

清华大学学报（自然科学版） 2023年第5期63卷 783-791页

作者：李大玉赵坤周魁斌孙鹏辉武金模南京工业大学安全科学与工程学院南京211816 清华大学合肥公共安全研究院合肥230601

聚甲基丙烯酸甲酯(PMMA)是主要的建筑装饰材料之一,一旦被点燃可能会导致严重的火灾事故。目前针对背板对PMMA向下火蔓延影响的实验研究较少。该文利用自主设计搭建的实验装置研究了背板对2mm和5mm厚PMMA向下火蔓延的影响。实验结果表明... 详细信息

聚甲基丙烯酸甲酯(PMMA)是主要的建筑装饰材料之一,一旦被点燃可能会导致严重的火灾事故。目前针对背板对PMMA向下火蔓延影响的实验研究较少。该文利用自主设计搭建的实验装置研究了背板对2mm和5mm厚PMMA向下火蔓延的影响。实验结果表明:背板对固体可燃物向下火蔓延存在抑制作用,具体表现为更大的热解前缘角度及更小的平均火焰高度、质量损失速率和火蔓延速率,该抑制作用在2mm厚度PMMA上更加明显。基于有无背板工况下的传热模型,结合燃烧稳定阶段样品热解区域形态参数,对质量损失速率及接收总热量反馈预测值大小进行对比,发现背板的存在会导致样品接收总热量反馈减少,进而导致更小的质量损失速率和火蔓延速率。

关键词：向下火蔓延热解前缘火蔓延速率质量损失速率传热

STEAM教育理念下初中美术课程的单元化教学设计

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基础教育研究 2023年第4期 72-74,84页

作者：孙鹏辉伊犁师范大学艺术学院伊宁839300

现代教育的培养目标和方向越来越指向创新型和复合型人才。STEAM教育强调跨学科性、情境性、协作性、体验性等教学理念和学习特点。文章以非物质文化遗产“皮影戏”为教学媒介,在美术学科核心素养的要求下,基于STEAM教育理念对初中美术... 详细信息

现代教育的培养目标和方向越来越指向创新型和复合型人才。STEAM教育强调跨学科性、情境性、协作性、体验性等教学理念和学习特点。文章以非物质文化遗产“皮影戏”为教学媒介,在美术学科核心素养的要求下,基于STEAM教育理念对初中美术课程进行单元化教学设计,通过真实情境的任务学习,培养学生创新能力、合作能力、运用多学科知识解决问题的能力等。这样的课堂教学不仅体现学科核心素养,而且还培养学生自主学习和独立思考的能力,使学生从中获得多元化、多角度、多学科交叉的学习体验。

关键词： STEAM教育理念初中美术教学设计

大型水电站EPC总承包工程监理管理要点浅析

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四川水力发电 2022年第6期41卷 129-131,136页

作者：孙鹏辉雅砻江流域水电开发有限公司四川成都610051

大型水电站EPC总承包模式下,监理工作较DBB模式下增加了勘察设计、设备物资采购、智能建设等板块监理工作,面临专业板块多、监理周期长和监理人员专业水平要求高等行业现状。委托人做好监理管理筹划工作对电站工程建设的顺利开展起着至... 详细信息

大型水电站EPC总承包模式下,监理工作较DBB模式下增加了勘察设计、设备物资采购、智能建设等板块监理工作,面临专业板块多、监理周期长和监理人员专业水平要求高等行业现状。委托人做好监理管理筹划工作对电站工程建设的顺利开展起着至关重要的作用,详细介绍了卡拉水电站主要阶段及相关专业板块监理管理工作主要做法,相关经验可为类似工程监理管理提供参考。

关键词：监理管理人员管理设计监理管理监理采购管理技术经济委员会卡拉水电站