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土地流转视角下农业数字化的增收效应

河南农业大学学报 2025年第1期59卷 155-166页

作者：张相龙赵梦典张海莹河南农业大学经济与管理学院河南郑州450046 中国农业科学院农业信息研究所北京100081

【目的】探究一定土地流转规模下农业数字化的增收效应。【方法】采用2011—2020年中国30个省(自治区、直辖市)面板数据,利用面板门限回归模型,以土地流转率为门限变量,分析农业数字化对农民的增收效应。【结果】土地流转规模需要达到... 详细信息

【目的】探究一定土地流转规模下农业数字化的增收效应。【方法】采用2011—2020年中国30个省(自治区、直辖市)面板数据,利用面板门限回归模型,以土地流转率为门限变量,分析农业数字化对农民的增收效应。【结果】土地流转规模需要达到一定程度才能够显著提高农业数字化的增收效应。不同地区土地流转程度对农业数字化的增收效应影响也不同,农业数字化的增收效应存在地区差异性,东部地区农业数字化的增收效应比中西部地区更为显著。土地流转与农业数字化相互促进,前者为后者提供了物理空间上的基础,后者则通过技术进步和产业升级进一步挖掘土地资源潜力,共同促进农民收入增长。【结论】继续完善土地流转市场,进一步缩小数字技术差距,加强培育新型农业经营主体。

关键词：农民收入农业数字化土地流转面板门限模型

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浅析傅青主论治血崩7法

江西中医药 2025年第1期56卷 21-22页

作者：张海英南京市秦淮区中医院妇科南京210006

通过对《傅青主女科·血崩》的研究,归纳出其治疗血崩的7种方法,对临床治疗血崩有重要指导意义。傅山将血崩分为妇人脾气虚弱,气血两虚;阴精既亏,肾火大动;肾精亏损,冲任不固;两相感召,旧精欲出;肝郁化火,热迫血行;瘀血内阻,血不归经;... 详细信息

通过对《傅青主女科·血崩》的研究,归纳出其治疗血崩的7种方法,对临床治疗血崩有重要指导意义。傅山将血崩分为妇人脾气虚弱,气血两虚;阴精既亏,肾火大动;肾精亏损,冲任不固;两相感召,旧精欲出;肝郁化火,热迫血行;瘀血内阻,血不归经;冲脉太热,扰动血海所致等7种类型。治疗上分别采用健脾益气,滋阴补血法;滋养精血,凉血止血法;益气健脾,补肾固胎法;引精外出,补气止血法;平肝开郁,清热止血法;活血化瘀,固经止血法;滋阴降火,清热止崩法。

关键词：傅青主血崩论治

Adaptive robust simultaneous stabilization of multiple nn-degree-of-freedom robot systems

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Control Theory and Technology 2022年第1期20卷 80-94页

作者： haiying zhang Renming Yang School of Information Science and Electrical Engineering Shandong Jiaotong UniversityJinan250357ShandongChina

In this paper,the adaptive robust simultaneous stabilization problem of uncertain multiple n-degree-of-freedom(n-DOF)robot systems is studied using the Hamiltonian function method,and the corresponding adaptive L2 controller is ***,we investigate the adaptive simultaneous stabilization problem of uncertain multiple n-DOF robot systems without external ***,the single uncertain n-DOF robot system is transformed into an equivalent Hamiltonian form using the unified partial derivative operator(UP-DO)and potential energy shaping method,and then a high dimensional Hamiltonian system for multiple uncertain robot systems is obtained by applying augmented dimension technology,and a single output feedback controller is designed to ensure the simultaneous stabilization for the higher dimensional Hamiltonian *** this basis,we further study the adaptive robust simultaneous stabilization control problem for the uncertain multiple n-DOF robot systems with external disturbances,and design an adaptive robust simultaneous stabilization ***,the simulation results show that the adaptive robust simultaneous stabilization controller designed in this paper is very effective in stabilizing multi-robot systems at the same time.

关键词： Multiple robot systems Adaptive robust control Simultaneous stabilization Hamiltonian function method

A RF receiver frontend for SC-UWB in a 0.18-μm CMOS process

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Journal of Semiconductors 2012年第12期33卷 49-55页

作者： Guo Rui zhang haiying Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China Shenyang Zhongke Microelectronics Co. LtdShenyang 110179China

A radio frequency （RF） receiver frontend for single-carrier ultra-wideband （SC-UWB） is presented. The front end employs direct-conversion architecture, and consists of a differential low noise amplifier （LNA）, a quadrature mixer, and two intermediate frequency （IF） amplifiers. The proposed LNA employs source inductively degenerated topology. First, the expression of input impedance matching bandwidth in terms of gate-source ca- pacitance, resonant frequency and target Sll is given. Then, a noise figure optimization strategy under gain and power constraints is proposed, with consideration of the integrated gate inductor, the bond-wire inductance, and its variation. The LNA utilizes two stages with different resonant frequencies to acquire flat gain over the 7.1-8.1 GHz frequency band, and has two gain modes to obtain a higher receiver dynamic range. The mixer uses a double bal- anced Gilbert structure. The front end is fabricated in a TSMC 0.18-μm RF CMOS process and occupies an area of 1.43 mm2. In high and low gain modes, the measured maximum conversion gain are 42 dB and 22 dB, input 1 dB compression points are -40 dBm and -20 dBm, and Sll is better than -18 dB and -14.5 dB. The 3 dB IF bandwidth is more than 500 MHz. The double sideband noise figure is 4.7 dB in high gain mode. The total power consumption is 65 mW from a 1.8 V supply.

关键词： radio frequency receiver front end CMOS low noise amplifier inductively degenerated single-carrier ultra-wideband

Experimental study of effect of post processing on fracture toughness and fatigue crack growth performance of selective laser melting Ti-6Al-4V

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Chinese Journal of Aeronautics 2019年第10期32卷 2383-2393页

作者： haiying zhang Dengke DONG Shaopu SU An CHEN Aircraft Strength Research Institute

For Ti-6Al-4V,a titanium alloy increasingly used in aerospace structure,selective laser melting(SLM)is an attractive additive manufacturing technology,which is attributed to its complex construction capability with high accuracy and good surface *** order to obtain qualified mechanical properties,SLM parameters and post processing should be tailored for diverse service *** toughness and fatigue crack growth(FCG)behavior are critical characteristics for damage tolerance evaluation of such metallic structures,and they are affected by post processing technologies *** objective of this study is to obtain the fracture toughness and fatigue crack growth behavior of Ti-6Al-4V manufactured by SLM,and to evaluate the influence of post-SLM thermomechanical treatment and surface *** toughness and FCG tests were performed for SLM Ti-6Al-4V in three types of post processing status:as-built,heat treated and hot isostatically pressed(HIPed),*** with as-built and machined surface were *** microstructure and fractography were analyzed as well in order to investigate the relevance among manufacture process,microstructure and mechanical *** results demonstrate that as-built SLM Ti-6Al-4V presents poor ductility and FCG behavior due to martensitic microstructure and residual *** heat treatment and hot isostatic pressing improve the plane-stress fracture toughness and FCG performance considerably,while surface machining shows slight effect.

关键词： Fracture toughness Fatigue crack growth Heat treatment Selective laser melting Surface roughness

基线血清HBV RNA水平对TDF治疗CHB合并进展期肝纤维化/代偿期肝硬化患者HBeAg血清学转换的预测价值

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中华检验医学杂志 2025年第1期48卷 49-55页

作者：张海莹王震宇贾玉缘陈红松饶慧瑛北京大学人民医院、北京大学肝病研究所、丙型肝炎和肝病免疫治疗北京市重点实验室、非酒精性脂肪性肝病诊断北京市国际科技合作基地北京100044 北京大学人民医院感染与肝病中心北京100044 北京大学人民医院肝病科北京100044

目的评估基线血清指标乙型肝炎病毒(HBV)RNA对富马酸替诺福韦酯(TDF)治疗慢性乙型肝炎(CHB)合并进展期肝纤维化/代偿期肝硬化患者乙型肝炎e抗原(HBeAg)血清学转换的预测价值。方法选取2015年1月至2020年12月在北京大学人民医院检测并经... 详细信息

目的评估基线血清指标乙型肝炎病毒(HBV)RNA对富马酸替诺福韦酯(TDF)治疗慢性乙型肝炎(CHB)合并进展期肝纤维化/代偿期肝硬化患者乙型肝炎e抗原(HBeAg)血清学转换的预测价值。方法选取2015年1月至2020年12月在北京大学人民医院检测并经TDF治疗的CHB合并进展期肝纤维化/代偿期肝硬化患者141例,进行回顾性病例对照研究。根据治疗240周时是否发生HBeAg血清学转换,将研究对象分为HBeAg血清学转换组(16例)和未转换组(59例)。根据基线和治疗12周的HBeAg结果,将研究对象分为HBeAg阳性组(分别为75、61例)和阴性组(分别为66、80例)。检测基线各相关指标水平,用基线、240周剩余血清检测HBV RNA水平。采用Pearson法分析HBV RNA与HBV DNA的相关性,受试者工作特征(ROC)曲线评价预测价值。结果75例HBeAg阳性患者中,21.3%(16/75)发生HBeAg血清学转换。基线HBeAg阳性组HBV DNA、HBV RNA水平均高于HBeAg阴性组(P均<0.001);HBeAg血清学转换组基线HBV RNA水平明显低于HBeAg血清学未转换组(P<0.05)。Pearson相关分析显示,在基线或12周HBeAg阴性组、HBeAg阳性组血清HBV RNA水平与HBV DNA均呈正相关(基线:r=0.718、0.794,P均<0.001;12周:r=0.689、0.750,P均<0.001)。ROC曲线显示,基线HBV RNA水平预测CHB合并进展期肝纤维化/代偿期肝硬化患者TDF治疗HBeAg血清学转换的曲线下面积为0.781,敏感度为75.0%,特异度为78.0%。结论基线血清HBV RNA水平对TDF治疗的CHB合并进展期肝纤维化/代偿期肝硬化患者HBeAg血清学转换具有预测价值。

关键词：慢性乙型肝炎肝纤维化代偿期肝硬化核苷类似物 HBV前基因组RNA 乙型肝炎e抗原血清学转换

Evaluation of the mold-filling ability of alloy melt in squeeze casting

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Journal of University of Science and Technology Beijing 2006年第1期13卷 60-66页

作者： haiying zhang Shuming Xing Qinghua zhang Jianbo Tan Wen Liu Semisolid Forming Research Center Beijing Jiaotong University Beijing 100044 China Shijiazhuang Locomotive Depot Shijiazhuang 050000 China Department of Material and Engineering Hebei University of Science and Technology Shijiazhuang 050018 China

The mold-filling ability of alloy mclt in squceze casting process was evaluated by means of the maximum length of Archimedes spiral line. A theoretical evaluating model to predict the maximum filling length was built based on the flowing theory of the incompressible viscous fluid. It was proved by experiments and calculations that the mold-tilling pressure and velocity are prominent influencing factors on the mold-filling ability of alloy melt. The mold-filling ability increases with the increase of the mold-filling pressure and the decrease of the proper mold-filling velocity. Moreover, the pouring temperature relatively has less effect on the mold-filling ability under the experimental conditions. The maximum deviation of theoretical calculating values with experimental results is less than 15%. The model can quantitatively estimate the effect of every factor on the mold-filling ability.

关键词： squeeze casting process parameters mold-filling ability theoretical calculation experimental evaluation

Compact lowpass filter with sharp roll-off and wide stopband using dual-stepped impedance resonator

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Science China(Information Sciences) 2014年第8期57卷 253-258页

作者： DU ZeBao YANG Hao zhang haiying ZHU Min Institute of Microelectronics Chinese Academy of Sciences

A lowpass filter unit with sharp roll-off and wide stopband using dual-stepped impedance resonator(DSIR)is *** lowpass filter unit is composed of DSIR,open circuited stubs,and high-impedance transmission *** mainly dominates the passband and stopband width while open stubs are used to enhance the suppression level with one transmission *** transmission zeros are introduced to stopband and one closed to passband ***,a very sharp transition can be achieved.A compact lowpass filter with sharp roll-off rate of 201 dB/octave,wide stopband of 5.9fc,and high suppression level of 30 dB was obtained when two asymmetric units were cascaded.

关键词： lowpass filter(LPF) sharp roll-off rate and stepped-impedance resonator

Influence of Water Stress on Endogenous Hormone Contents and Cell Damage of Maize Seedlings

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Journal of Integrative Plant Biology 2008年第4期50卷 427-434页

作者： Chunrong Wang Aifang Yang haiying Yin Juren zhang School of Life Sciences Shandong University Jinan 250100 China

Phytohormones play critical roles in regulating plant responses to stress. We investigated the effects of water stress induced by adding 12% （w/v） polyethylene glycol to the root medium on the levels of abscisic acid （ABA）, indole-3-acid （IAA）, zeatin （ZT）, and gibberellin3 （GA3） in maize leaves. The results suggested that water stress had significant effects on the four hormone levels. There was a transient increase in the IAA content during the initial stage of adaptation to water stress in maize leaves, but it dropped sharply thereafter in response to water stress. ABA content increased dramatically in maize leaves after 24 h of exposure to water stress, and then the high levels of ABA were maintained to the end. The contents of ZT and GA3 rapidly declined in maize leaves subjected to water stress. The effects of water stress on chlorophyll content, electrolyte leakage and malondialdehyde levels in maize leaves were also studied. The variation of cell damage was negatively correlated with ZT and GA3 levels in maize leaves under water stress. Thus, we explored the roles of ZT and GA3 on the growth of maize seedlings under water stress by exogenous application. It is possible that both ZT and GA3 were effective in protecting maize seedlings from water stress, which would be of great importance for the improvement of drought tolerance in maize by genetic manipulation.

关键词： cell damage maize phytohormones water stress.