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准Z源逆变器的模型预测电流误差控制

电力系统及其自动化学报 2024年第3期36卷 142-150页

作者：许宇豪李文真肖海峰贺昱曜康雪娟西安航空学院电子工程学院西安710077 西安航空学院车辆工程学院西安710077 西北工业大学航海学院西安710072

为降低准Z源逆变器模型预测控制的控制误差,提出一种模型预测电流误差控制方法。首先,在充分分析电压矢量对被控量性能影响的基础上,合理地选择适合各被控量的电压矢量组合方式。然后,利用电流对称控制思想保证电感电流关于其参考指令... 详细信息

为降低准Z源逆变器模型预测控制的控制误差,提出一种模型预测电流误差控制方法。首先,在充分分析电压矢量对被控量性能影响的基础上,合理地选择适合各被控量的电压矢量组合方式。然后,利用电流对称控制思想保证电感电流关于其参考指令对称。最后,采用电压矢量抵消原理使输出电流幅值逼近其目标值。实验结果表明,所提方法能够大幅降低电感电流脉动和输出电流谐波含量;证明了所提方法能有效提高准Z源逆变器的控制精度,简化了对权重系数的设计工作。

关键词：模型预测控制准Z源逆变器电感电流脉动输出电流谐波

制造业转型升级背景下的增材制造人才培养体系的构思与实施路径

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创新创业理论研究与实践 2024年第7期7卷 87-89页

作者：肖海峰刘峰李峰光湖北汽车工业学院材料科学与工程学院湖北十堰442000

该文以汽车产业为例,以应用型人才培养为主要研究对象,分析制造产业的发展现状及其对增材制造人才需求的转变,找出解决校、企之间人才供需问题的关键,结合增材制造专业应用型人才的特点,确定了“宽基础、重应用、宽专适度”的人才培养定... 详细信息

该文以汽车产业为例,以应用型人才培养为主要研究对象,分析制造产业的发展现状及其对增材制造人才需求的转变,找出解决校、企之间人才供需问题的关键,结合增材制造专业应用型人才的特点,确定了“宽基础、重应用、宽专适度”的人才培养定位,重构人才培养体系,建立健全质量保障机制,开辟了以校企合作为平台、以校企双向导师制度为保障、以工程项目实践为核心的增材制造专业人才培养的实施路径。

关键词：增材制造专业人才培养体系应用型人才汽车产业人才供需问题质量保障

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野战条件下开展动物腹腔镜手术的方法体会

联勤军事医学 2024年第1期38卷 60-62页

作者：肖海峰薛姣刘晓雷董兴宝联勤保障部队987医院麻醉科陕西宝鸡721000 联勤保障部队987医院门诊部陕西宝鸡721000 联勤保障部队987医院卫勤处陕西宝鸡721000 空军军医大学唐都医院检验科

目的总结野战条件下开展动物腹腔镜手术的方法,为野战条件下使用腹腔镜救治闭合性腹部战创伤进行探索。方法在医疗队外训期间,选择山羊3只(A、B、C),每只山羊实施两次手术,两次手术间隔2天,使用临床常用麻醉药进行不插管全麻,麻醉成功... 详细信息

目的总结野战条件下开展动物腹腔镜手术的方法,为野战条件下使用腹腔镜救治闭合性腹部战创伤进行探索。方法在医疗队外训期间,选择山羊3只(A、B、C),每只山羊实施两次手术,两次手术间隔2天,使用临床常用麻醉药进行不插管全麻,麻醉成功后首先对腹腔进行探查,采用人工方法建立肠破裂模型,对破裂肠壁进行缝合。记录山羊的血氧饱和度、心率、术中体动次数、出血量,记录腹腔探查时间、手术时间(开始切皮至缝皮结束时间)。结果3只山羊术中生命体征平稳,麻醉及手术过程顺利,术后苏醒迅速,抬离手术台后均能站立行走,正常存活。结论在不插管全麻条件下开展动物腹腔镜手术,麻醉管理方便,腹部战创伤手术全流程训练均可实现,表明野战条件下使用腹腔镜救治腹部战创伤具有可行性。

关键词：野战训练动物腹腔镜微创手术

Palynological evidence for vegetational and climatic changes from the HQ deep drilling core in Yunnan Province, China

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Science China Earth Sciences 2007年第8期50卷 1189-1201页

作者： xiao XiaYun SHEN Ji WANG SuMin xiao haifeng TONG GuoBang Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China Institude of Hydrogeology and Engineering Geology Chinese Academy of Geological SciencesShijiazhuang 050061China

The high-resolution pollen study of a 737.72-m-long lake sediment core in the Heqing Basin of Yunnan Province shows that the vegetation and climate of mountains around the Heqing Basin went through six obvious changes since 2.780 Ma B.P. Namely, Pinus forest occupied most mountains around the studied area and the structure of vertical vegetational belt was simple between 2.780 and 2.729 Ma B.P., reflecting a relatively warm and dry climate. During 2.729―2.608 Ma B.P., the areas of cold-temperate conifer forest (CTCF) and Tsuga forest increased and the structure of vertical vegetational belt became clear. According to percentages of tropical and subtropical elements growing in low-altitude regions rifely increased, we speculate that the increase of CTCF and Tsuga forest areas mainly resulted from strong uplift of mountains which provided upward expanding space and growing condition for these plants. Thus, the climate of the low-altitude regions around the basin was relatively warm and humid. Between 2.608 and 1.553 Ma B.P., Pinus forest occupied most mountains around the studied area and forest line of CTCF rose, which reflects a moderately warm-dry climate on the whole. During 1.553―0.876 Ma B.P., the structure of vertical vegetational belt in mountains around the studied area became complicated and the amplitude of vegetational belts shifting up and down enlarged, which implies that the amplitude of climatic change increased, the climatic associational feature was more complex and the climate was moderately cold at a majority of the stage. During 0.876―0.252 Ma B.P., there were all vertical vegetational belts existing at present in mountains around the studied area. The elements of each belt were more abundant and complex than earlier. At different periods in the stage vertical vegetational belts occurred as expanding or shrinking, and alternated each other. The amplitude of vegetational belts shifting up and down was the maximum in the whole section. This change s

关键词： pollen record palaeovegetation palaeoclimate climatic transition Heqing Basin

Assessment of Sustainable Development System in Suihua City, China

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Chinese Geographical Science 2007年第4期17卷 304-310页

作者： ZHOU Jia xiao haifeng SHANG Jincheng ZHANG Xuelin College of Life and Environment Sciences Harbin Normal University Harbin 150025 China Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China College of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China

Sustainable development is a complex and systemic issue. It is essential to study it by the component analysis method from the view of system science. The urban developmental sustainability is one of focuses that people has paid more attention to, however, little common understanding how to measure and evaluate the sustainability has been gotten. In this paper, a framework is designed to evaluate the developmental sustainability of Suihua City, Heilongiiang Province in China from the aspects of economy, society, population, resources and environment. We adopt the Principal Components Analysis （PCA） to decrease dimensions and simplify the original indexes into 12 indexes. Also, the hierarchy and comprehensive multiple-criterion evaluative methods are employed to assess the sustainable development system in Suihua City. Then, the weights of indexes are attained by Analytic Hierarchy Process （AHP） method. Furthermore, urban comprehensive development level, developmental sustainability, coordinate degree are calculated and analyzed. By analyzing, we know the fluctuation of development level of subsystem, especially resources and environment subsystem, is acute. The comprehensive development level of sustainable development system in Suihua has been on the rise since 1999. That results from the effect of traditional economic development mode with high energy-consumed being decreased in the city after 1999. At the same time, it is obvious that there was an instability of development level in Suihua City during 1990-2002, the status＇trend was more harmonious in 1999-2002. with a turn in 1998, and the development could be sustainable,

关键词： sustainable development comprehensive development level developmental sustainability coordinate degree Suihua City

The plant diversity and its relationship with paleoenvironment since 2.78 Ma revealed by pollen records in the Heqing deep drilling core

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Chinese Science Bulletin 2008年第23期53卷 3686-3698页

作者： xiao XiaYun SHEN Ji WANG SuMin xiao haifeng TONG GuoBang State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Department of Geography Harbin Normal University Harbin 150084 China Institute of Hydrogeology and Engineering Geology Chinese Academy of Geological Sciences Shijiazhuang 050061 China

Multifold palynological diversity indices calculated by pollen data of the Heqing deep drilling core are synthetically analyzed, the results show that the plant diversity rapidly increased and its fluctuant amplitude and frequency evidently largened during the stages of 2.729―2.608 Ma, 1.176―0.342 Ma and since 0.118 Ma respectively, while during the other periods the plant diversity was relatively low with a gentle fluctuation. To discuss further the relation between ancient plant diversity and paleoenvironment, it is considered that the plant diversity in the Heqing region lies on increase or decrease of vertical vegetational belts in mountains around the studied area and richness of components of these vegetational belts, and is controlled by amplitude of tectonic uplift of mountains and climatic changes. The high plant diversity during 2.729―2.608 Ma responded to the strong uplift of mountains at the stage, while the plant diversity greatly increased and its fluctuant amplitude and frequency markedly largened at about 1.176 Ma was obviously response to the Middle Pleistocene Transition. The plant diversity and its fluctuant amplitude and frequency increased further at about 0.991 Ma may be superposably affected by both the Middle Pleistocene Transition and the tectonic uplift. The plant diversity increased since 0.118 Ma may indicate that the southwest monsoon strengthened and humid climate more fitted many kinds of plants to grow.

关键词：花粉传播植物多样性地质气候盆地

Compensation of Dead-time Effects Based on Adaptive Voltage Disturbance Estimator in PMSM Drives

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Compensation of Dead-time Effects Based on Adaptive Voltage ...

The orbital scale evolution of regional climate recorded in a long sediment core from Heqing,China

第26届中国控制与决策会议

作者： xiao haifeng He Yuyao Northwestem Polytechnical University

ISBN: (纸本)9781479937066

To suppress the phase current distortions of the inverter in permanent-magnet synchronous motor（PMSM） drive, an effective online approach for dead-time compensation of the inverter control using a simple disturbance voltage estimator is proposed. The dead-time elimination scheme does not depend on some undesirable characteristics of inverter, such as dead-time, turn-on/off time of switching devices, and voltage drop of switching devices. The proposed method can easily calculate the disturbance voltages, which is induced by the relationship between variation of the current（e dΔie qΔi） and the increment of the opposing electromotive force within a sampling period according to the rotor dynamics lagging behind the electromagnetic responses in the rotor synchronous reference frame. Then, the compensation of dead-time effect can be easily implemented by feedforwardly adding compensation voltages to the output reference voltage in the current control loop. This validity of the proposed compensation algorithm is shown through several simulations and experiments on a 4.5-KW laboratory PMSM drive.

关键词： Index Terms Voltage space vector PMSM dead-time effect disturbance voltage.

来源： cnki会议评论

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Chinese Science Bulletin 2007年第13期52卷 1813-1819页

作者： SHEN Ji xiao haifeng WANG SuMin AN ZhiSheng QIANG xiaoKe xiao XiaYun Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Department of Geography Harbin Normal University Harbin150025china Institute of Earth and Environment Chinese Academy of Sciences Xi'an 710075 China

Based on the analysis of carbonate content and loss on ignition for a long sediment core (737 m in length) drilled in Heqing, the orbital scale evolution of the Southwest Monsoon is revealed, by using overlapped spectral analysis and filter methods. It is shown that the obliquity cycle and precession cycle are the key factors for the Southwest Monsoon evolution and that the change of the global ice volume and the uplift of the Qinghai-Tibetan Plateau also impose great influences on it.

关键词：沉淀物太平洋季风气候

AN EFFECTIVE NETWORK CONGESTION CONTROL METHOD FOR MULTILAYER NETWORK

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Journal of Electronics(China) 2008年第4期25卷 488-494页

作者： Du haifeng xiao Yang Lu Lingyun Institute of Information and Science Beijing Jiaotong University Beijing 100044 China

The congestion control problem in a single node network has been solved by the nonlinearfeedback control method,which has been proven to be effective and robust for different router’s ***,these control models are based on the single layer network architecture,and the sendersand receivers are directly connected by one pair of *** the network architecture being moreand more complex,it is a serious problem how to cooperate many routers working in the multilayernetwork *** this paper,an effective Active Queue Management(AQM)scheme toguarantee the stability by the nonlinear control of imposing some restrictions on AQM parameter inmultilayer network is *** nonlinear control can rely on some heuristics and network trafficcontrollers that appear to be highly correlated with the multilayer network *** proposedmethod is based on the improved classical Random Early Detection(RED)differential equation and atheorem for network congestion *** theorem proposed in the paper proved that the stability ofthe fluid model can effectively ensure the convergence of the average rate to its equilibrium pointthrough many routers in multilayer ***,when the network capacity is larger,theproposed scheme can still approach to the fullest extensibility of utilization and ensure the stability ofthe fluid *** paper reveals the reasons of congestion control in multilayer network,provides atheorem for avoiding network congestion,and gives simulations to verify the results.

关键词： Active Queue Management (AQM) Nonlinear control Transmission Control Protocol (TCP) Random Early Detection (RED) Multilayer network