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Assessment of Soil Erosion by Compensatory Hoeing Tillage in a Purple Soil

Journal of Mountain Science 2012年第1期9卷 59-66页

作者： SU Zhengan zhang jianhui XIONG Donghong LIU Gangcai Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Aeademy of SciencesChengdu 610041China

This study explores the role of a traditional tillage method,i.e.,compensatory hoeing,for sustainable agro-ecosystem management in the hilly areas of the Chongqing municipality,south-western *** validate the effects of compensatory tillage on the terraced slopes,the tillage method of noncompensatory hoeing was conducted on a linear *** acquire information about 137 Cs inventories and soil texture,soil samples were collected by a core sampler with a 6.8-cm diameter at 5.0-m intervals along the toposequence and the linear slope in the dry season(March) of ***,a tillage erosion model was used for evaluating the spatial pattern of tillage *** 137 Cs data showed that on the terraced slope,soil was lost from the upper slope,and soil deposition occurred at the toe slope positions on each *** a result,abrupt changes in the 137 Cs inventories of soil were found over short distances between two sides of terrace *** obtained from the tillage erosion model and the 137 Cs data indicate that soil redistribution mainly results from tillage erosion in the terraced *** non-compensatory tillage caused soil redistribution on the linear slope,resulting in thin soil profile disappearing at the top and soil accumulating at the bottom positions of the linear *** result further validates that compensatory tillage could avoid the complete erosion of the thin soil layer at the summit ***,this traditional ***,i.e.,compensatory tillage,has maintained the soil quality at the summit of the slope in the past decades.

关键词： Compensatory tillage Tillage erosion model 137 Cs Three Gorges Reservoir region China

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Advances in Photoacoustic Imaging for Interventional Application

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第6期35卷 924-941页

作者： zhang jianhui Yan Kang Wang Boquan zhang Buchun Gong Xiaojing School of Mechanical and Electric Engineering Guangzhou University State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Research Lab for Biomedical Optics and Molecular Imaging Shenzhen Institutes of Advanced TechnologyChinese Academy of Sciences Department of Cardiology The Affiliated Hospital of Xuzhou Medical University

The incidence and mortality of cardiovascular diseases and gastrointestinal cancer have gradually increased in recent years,and these diseases have become major social and public-health *** requirements have been proposed for the clinical diagnosis of these diseases in the hope that,by accessing accurate structural information,to further grasp the functional information which closely related to the development of the *** imaging is a new imaging method in which ultrasonic signals are generated from biological samples by laser-pulse *** has the advantages of high optical contrast,large ultrasound penetration depth,and high ***,it can acquire spectral *** integration of a photoacoustic imaging system into a tiny imaging catheter can realize interventional imaging based on photoacoustic *** combination of structural imaging of cardiovascular and gastrointestinal lesion regions with photoacoustic spectroscopy to identify and quantify tissue components can realize highly sensitive functional *** surveying the recent progress in the development of the photoacoustic imaging method for interventional application,with a particular emphasis on intravascular photoacoustic imaging,photoacoustic endoscopy,and photoacoustic spectroscopy,we summarize and identify future research directions for interventional photoacoustic imaging.

关键词： photoacoustic imaging interventional intravascular photoacoustic imaging photoacoustic endoscopy photoacoustic spectroscopy

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Simulation Analysis and Experimental Verification of Spiral-tube-type Valveless Piezoelectric Pump with Gyroscopic Effect

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 822-829页

作者： LENG Xuefei zhang jianhui JIANG Yan WANG Shouyin ZHAO Chunsheng College of Astronautics Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

The current research of the valveless piezoelectric pump focuses on increasing the flow rate and pressure differential. Compared with the valve piezoelectric pump, the valveless one has excellent performances in simple structure, low cost, and easy miniaturization. So, their important development trend is the mitigation of their weakness, and the multi-function integration. The flow in a spiral tube element is sensitive to the element attitude caused by the Coriolis force, and that a valveless piezoelectric pump is designed by applying this phenomenon. The pump has gyroscopic effect, and has both the actuator function of fluid transfer and the sensor function, which can obtain the angular velocity when its attitude changes. First, the present paper analyzes the flow characteristics in the tube, obtains the calculation formula for the pump flow, and identifies the relationship between pump attitude and flow, which clarifies the impact of flow and driving voltage, frequency, spiral line type and element attitude, and verifies the gyroscopic effect of the pump. Then, the finite element simulation is used to verify the theory. Finally, a pump is fabricated for experimental testing of the relationship between pump attitude and pressure differential. Experimental results show that when Archimedes spiral θ=4π is selected for the tube design, and the rotation speed of the plate is 70 r/min, the pressure differential is 88.2 Pa, which is 1.5 times that of 0 r/min rotation speed. The spiral-tube-type valveless piezoelectric pump proposed can turn the element attitude into a form of pressure output, which is important for the multi-function integration of the valveless piezoelectric pump and for the development of civil gyroscope in the future.

关键词： gyroscope valveless piezoelectric pump spiral tube

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A Distributed Decision Mechanism for Controller Load Balancing Based on Switch Migration in SDN

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China Communications 2018年第10期15卷 129-142页

作者： Tao Hu Peng Yi jianhui zhang Julong Lan National Digital Switching System Engineering & Technological R&D Center Zhengzhou 450002 China

Software Defined Networking(SDN) provides flexible network management by decoupling control plane from data plane. And multiple controllers are deployed to improve the scalability and reliability of the control plane, which could divide the network into several subdomains with separate controllers. However, such deployment introduces a new problem of controller load imbalance due to the dynamic traffic and the static configuration between switches and controllers. To address this issue, this paper proposes a Distribution Decision Mechanism(DDM) based on switch migration in the multiple subdomains SDN network. Firstly, through collecting network information, it constructs distributed migration decision fields based on the controller load condition. Then we choose the migrating switches according to the selection probability, and the target controllers are determined by integrating three network costs, including data collection, switch migration and controller state synchronization. Finally, we set the migrating countdown to achieve the ordered switch migration. Through verifying several evaluation indexes, results show that the proposed mechanism can achieve controller load balancing with better performance.

关键词： software defined networking controller load balancing switch migration distributed decision

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Theoretical Calculations and Experimental Verification for the Pumping Effect Caused by the Dynamic Micro-tapered Angle

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 615-623页

作者： CAI Yufei zhang jianhui ZHU Chunling HUANG Jun JIANG Feng College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Electro-Mechanical Engineering Guangzhou University State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Research Center of Fluid Machinery Engineering and Technology Jiangsu University

The atomizer with micro cone apertures has advantages of ultra-fine atomized droplets, low power consumption and low temperature rise. The current research of this kind of atomizer mainly focuses on the performance and its application while there is less research of the principle of the atomization. Under the analysis of the dispenser and its micro-tapered aperture＇s deformation, the volume changes during the deformation and vibration of the micro-tapered aperture on the dispenser are calculated by coordinate transformation. Based on the characters of the flow resistance in a cone aperture, it is found that the dynamic cone angle results from periodical changes of the volume of the micro-tapered aperture of the atomizer and this change drives one-way flows. Besides, an experimental atomization platform is established to measure the atomization rates with different resonance frequencies of the cone aperture atomizer. The atomization performances of cone aperture and straight aperture atomizers are also measured. The experimental results show the existence of the pumping effect of the dynamic tapered angle. This effect is usually observed in industries that require low dispersion and micro- and nanoscale grain sizes, such as during production of high-pressure nozzles and inhalation therapy. Strategies to minimize the pumping effect of the dynamic cone angle or improve future designs are important concerns. This research proposes that dynamic micro-tapered angle is an important cause of atomization of the atomizer with micro cone apertures.

关键词： atomization nozzle/diffuser flow dynamic cone angle piezoelectric pump

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医院多院区智能化系统互联的应用分析

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智能建筑电气技术 2024年第4期18卷 106-110页

作者：胡宇光赵鹏张建辉北京市建筑设计研究院股份有限公司北京100045

针对医院新老院区医疗、安防、建筑设备等信息的融合问题,本文以我国某省人民医院新院区智能化专项设计为例,探讨解决新院区与已建成的两个院区之间的智能化系统互联互通问题,分析了智能化机房设置、网络互联架构的多种方案选择,以及院... 详细信息

针对医院新老院区医疗、安防、建筑设备等信息的融合问题,本文以我国某省人民医院新院区智能化专项设计为例,探讨解决新院区与已建成的两个院区之间的智能化系统互联互通问题,分析了智能化机房设置、网络互联架构的多种方案选择,以及院区互联中运营商网络的方案比选,以供参考。

关键词：智能化设计院区互联网络设计

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A spiral-tube-type valveless piezoelectric pump with gyroscopic effect

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Chinese Science Bulletin 2014年第16期59卷 1885-1889页

作者： jianhui zhang Xuefei Leng Chunsheng Zhao State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics College of Astronautics Nanjing University of Aeronautics and Astronautics

The valveless piezoelectric pump integrates driving and transmitting into one operating element,and characterizes easy ***,there is the original sin of low pressure and low ***,it must avoid weakness to choose applications *** paper analyzes the flow characteristics in the rotary spiral-tube,which will cause the Coriolis force,and subsequently influence the fluid *** principle of the pump is deduced,and the spiral-tube-type valveless piezoelectric pump is *** angular velocity variation can be obtained when the pump attitude changes,which theoretically verifies the gyroscopic effect of the pump.A pump is fabricated for experimental *** has shown that when Archimedes spiral h?4p is selected for the tube design,and the rotation speed of the plate is 70 r/min,the pressure differential is 9 mm H2O,which is 1.5 times that of 0 r/min rotation *** introduced the low-cost and miniaturized gyroscope,then this may promise potential application in these areas such as smart cars,robots,and home health care.

关键词：无阀压电泵陀螺效应管型螺旋型阿基米德螺旋线旋转速度实验测试科里奥利力

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浅析检影验光中模拟眼与人眼的区别

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玻璃搪瓷与眼镜 2024年第5期52卷 15-19页

作者：张琪李文娟张建辉武文黄骅视光眼科医院沧州061110 天津职业大学天津300410

模拟眼和人眼有本质区别,模拟眼是1个简单的屈光系统,检影上手容易;而人眼不仅仅是1个屈光系统,还有晶体调节、瞳孔变化等机制,人眼检影操作困难。模拟眼检影是检影验光学习的基础,只有充分掌握检影技巧,熟练检影后才可以进行人眼检影。

关键词：模拟眼人眼检影晶状体瞳孔对光反射

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需求驱动的跨领域专利技术挖掘方法构建

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科技管理研究 2024年第14期44卷 154-163页

作者：丁照琪张建辉许辰辉河北工业大学机械工程学院天津300401 河北工业大学国家技术创新方法与实施工具工程技术研究中心天津300401

如何从大量的专利信息中快速准确地发掘与企业产品相关的专利技术,仍然是产业界和学术界面临的难题之一。兴奋型需求往往是企业发掘的对象和产品进化的方向,因而,从企业产品创新的需求出发,提出一种需求驱动的跨领域专利技术挖掘方法:... 详细信息

如何从大量的专利信息中快速准确地发掘与企业产品相关的专利技术,仍然是产业界和学术界面临的难题之一。兴奋型需求往往是企业发掘的对象和产品进化的方向,因而,从企业产品创新的需求出发,提出一种需求驱动的跨领域专利技术挖掘方法:通过需求功能映射和功能泛化建立专利检索式,从专利数据库中检索专利,在专利检索式的基础上依据国际专利分类(IPC)进行拓展以保证专利挖掘数据的广泛性,并且通过对专利技术特征、引用关系、法律状态等多个方面的分析,实现对跨领域专利技术的挖掘。该方法使用自然语言处理技术,通过对专利数据的提取和分析,完成跨领域专利技术挖掘、形成了早期方案,并基于技术系统进化理论对所挖掘专利进行创新性评价。通过油烟机实例研究表明,该专利挖掘方法通过功能拓展和IPC分类号的应用,能够全面检索到与目标产品功能相关的专利信息,提高挖掘结果的准确性;且在专利挖掘过程中,引入法律信息、专利引用情况和专利技术文本相似度等指标,并可利用计算机辅助完成大部分工作,能够节省人力资源,提高专利挖掘效率和速度。

关键词：专利挖掘需求驱动专利信息技术特征传递信息提取技术系统进化理论产品创新

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Principle and Experimental Verification of Caudal-fin-type Piezoelectric-stack Pump with Variable-cross-section Oscillating Vibrator

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 128-136页

作者： HU Xiaoqi zhang jianhui HUANG Yi XIA Qixiao HUANG Weiqing ZHAO Chunsheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical&Electronic Engineering Beijing Union UniversityBeijing 100020China

In the traditional flow-resistance-differential (FRD) type valve-less piezoelectric pump, the generated outflow and pressure are discontinuous because of the inherent periodicity and fluctuation of the pump. To overcome these drawbacks, utilizing the bending vibration of piezoelectric bimorph to drive fluid was conducted. However, our investigation on the current status of this piezoelectric bimorph pump shows that larger driving force and vibration amplitude are required for fluid pumping; the pumping can be realized through the centrifugal force; and the mechanism of fluid pumping is no longer further studied. Based on these cases, the paper designed a piezoelectric-stack pump with variable-cross-section oscillating (VCSO) vibrator by imitating the swing of the caudal-fin of tuna, and the pump is neither the rotating type nor the volumetric type according to the taxonomy. The interaction between the oscillating vibrator and the fluid parcel is firstly analyzed from the viewpoint of momentum conservation, and the analytical expression of pump flow rate is obtained. Then the modal and harmonic response analyses on the vibrator immerged in water are carried out. From the analyses the first two orders resonance frequencies are 832 Hz and 1 939 Hz, respectively, and the peak value of the tip amplitude is 0.6 mm. Laser Doppler vibrometer is used to measure both the frequency and vibration amplitude, and the determined first two orders resonance frequencies are 617 Hz and 1 356 Hz, respectively. The measured tip amplitude reaches to the peak value of 0.3 mm. At last, experimental measurement for the flow rates with different driving frequencies is conducted. The results show that the flow rate can reach 560 mL/min at 1 370 Hz when the pump runs under the backpressure of 30 mm water column. And the flow rate is as much as 560% of that of experiment results carried out by researchers from Brazil. The proposed pump innovates in both theory and taxonomy; in addition, the pum

关键词： caudal-fin-type variable-cross-section piezoelectric-stack valve-less pump

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