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基于单目视觉感知的分闸开关定位方法研究

机械设计与制造 2024年第9期 266-270页

作者：方励云周唯逸朱星翰王龙国网浙江电力有限公司乐清市供电公司浙江温州325600 中国计量大学机电工程学院浙江杭州310018

针对智能变电站机器人在进行分闸作业时定位精度过低的问题,对基于单目视觉感知的定位方法进行了研究,并建立了单目视觉定位方案。首先针对变电站复杂的室内成像环境影响,设计了一种基于图像亮度均衡强化的阈值分割算法,可以从图像中准... 详细信息

针对智能变电站机器人在进行分闸作业时定位精度过低的问题,对基于单目视觉感知的定位方法进行了研究,并建立了单目视觉定位方案。首先针对变电站复杂的室内成像环境影响,设计了一种基于图像亮度均衡强化的阈值分割算法,可以从图像中准确提取开关的轮廓边缘信息;然后设计了一种基于RANSAC的椭圆拟合算法,对轮廓边缘信息进行拟合得到开关的位置信息;最后设计了基于灰度特征的快速匹配算法,并且融合了金字塔匹配策略,提高了匹配速度和抗干扰能力。实验结果表明,该方法的开关位置定位精度为±0.8mm,角度定位精度为±0.9°,且定位效率高,鲁棒性好,满足变电站机器人分闸作业的要求。

关键词：单目视觉定位识别阈值分割椭圆拟合快速匹配金字塔匹配

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Improved direct power control of a grid-connected voltage source converter during network unbalance

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第10期11卷 817-823页

作者： Peng zhou wei ZHANG yi-kang HE Rong ZENG School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper deals with an improved direct power control(DPC) strategy for the pulse width modulation(PWM) voltage source converter(VSC) under unbalanced grid voltage *** order to provide enhanced control performance for the VSC,the resonant controllers tuned at the double grid frequency are applied in the DPC design to eliminate the power pulsations and dc link voltage ripples produced by the transient unbalanced grid *** this way,the output power and dc link voltage of the VSC can be directly regulated without positive and negative sequential *** a result,and as has been verified by experiment,the proposed method can provide fast dynamic response with easy implementation.

关键词： Voltage source converter Direct oower control Unbalance Resonant controller

Some Physiological Processes Related to Water Use Efficiency of Higher Plants

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Agricultural Sciences in China 2006年第6期5卷 403-411页

作者： GUO Shi-wei zhou yi SONG Na SHEN Qi-rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 P.R.China

Water use efficiency （WUE） of higher plants is of vital importance in the dry-land agricultural ecosystem in terms of the development of water-saving agriculture. Of all the approaches used to improve WUE, the intrinsic water use efficiency （WUET, the ratio of CO2 assimilation rate to transpiration rate） can be a right index, as the variation of WUET is correlated with the physiological and biochemical processes of higher plants. The measurements of leaf gas exchange and carbon isotope discrimination （D^13C） are the two ways to detect the variation in WUEr. This article reviewed some physiological processes related to WUEv, including the relationship between CO2 assimilation and stomatal conductance and WUET and water absorption. The relationship between WUE and aquaporin and the yield are discussed as well.

关键词： water use efficiency gas exchange carbon isotope discrimination water channel

Intrinsic correlation between the generalized phase equilibrium condition and mechanical behaviors in hydrate-bearing sediments

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2822-2832页

作者： Jiazuo zhou Changfu wei Rongtao Yan Yuan zhou yi Dong Hubei Key Laboratory of Marine Geological Resources College of Marine Science and TechnologyChina University of GeosciencesWuhanChina State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhanChina Guangxi Key Laboratory of New Energy and Building Energy Saving College of Civil Engineering and ArchitectureGuilin University of TechnologyGuilinChina

The phase equilibrium and mechanical behaviors of natural gas hydrate-bearing sediment are essential for gas recovery from hydrate *** heating closed systems,the temperature-pressure path of hydrate-bearing sediment deviates from that of pure bulk hydrate,reflecting the porous media effect in phase equilibrium.A generalized phase equilibrium equation was established for hydrate-bearing sediments,which indicates that both capillary and osmotic pressures cause the phase equilibrium curve to shift leftward on the temperature-pressure *** contrast to bulk hydrate,hydrate-bearing sediment always contains a certain amount of unhydrated water,which keeps phase equilibrium with the hydrate within the hydrate stability *** changes in temperature and pressure,a portion of pore hydrate and unhydrated water may transform into each other,affecting the shear strength of hydrate-bearing sediment.A shear strength model is proposed to consider not only hydrate saturation but also the change in temperature and pressure of hydrate-bearing *** model is validated by experimental data with various hydrate saturation,temperature and pressure *** deformation induced by partial dissociation was studied through depressurization tests under constant effective *** reduction in gas pressure within the hydrate stability field indeed caused sediment *** dissociation-induced deformation can be reasonably estimated as the difference in volume between hydrate-bearing and hydrate-free sediments from the compression curves.

关键词： Hydrate-bearing sediment Generalized phase equilibrium Unhydrated water Partial dissociation Mechanical behavior

Membrane Phospholipid Redistribution in Cytokinesis:A Theoretical Model

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Acta Biochimica et Biophysica Sinica 2005年第9期37卷 643-648页

作者： Mei-Wen AN Wen-zhou WU wei-yi CHEN Institute of Applied Mechanics,Taiyuan University of Technology,Taiyuan 030024,China Institute of Applied Mechanics Taiyuan University of TechnologyTaiyuan 030024 China

In cell mitosis,cytokinesis is a major deformation process,during which the site of thecontractile ring is determined by the biochemical stimulus from asters of the mitotic apparatus,actin andmyosin assembly is related to the motion of membrane phospholipids,and local distribution and arrangementof the microfilament cytoskeleton are different at different cytokinesis *** on the Zinemanas-Nirmodel,a new model is proposed in this study to simulate the entire process by coupling the biochemicalstimulus with the mechanical *** were three assumptions in this model:the movements ofphospholipid proteins are driven by gradients of biochemical stimulus on the membrane surface;the localassembly of actin and myosin filament depends on the amount of phospholipid proteins at the same location;and the surface tension includes membrane tensions due to both the passive deformation of the membraneand the active contraction of actin filament,which is determined by microfilament redistribution *** model could explain the dynamic movement of microfilaments during cytokinesis andpredict cell *** calculated results from this model demonstrated that the reorientation ofphospholipid proteins and the redistribution and reorientation of microfilaments may play a crucial role in *** model may better represent the cytokinesis process by the introduction of biochemical stimulus.

关键词： cytokinesis biochemical stimulus phospholipid actomyosin microfilament

New Insights into the Nitrogen Form Effect on Photosynthesis and Photorespiration

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Pedosphere 2007年第5期17卷 601-610页

作者： GUO Shi-wei zhou yi GAO ying-Xu LI Yong SHEN Qi-Rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）

Under high light conditions, ammonium nutrition has a negative effect on plant growth. This suggests that the adverse effects of ammonium nutrition on plant growth may be related to carbon gain, photosynthesis, and photorespiration. However, there is no consistent evidence of a specific mechanism that could explain the plant growth reduction under ammonium supply. It is generally accepted that during the light reaction, a surplus of nicotinamide adenine dinucleotide hydrogen phosphate （NADPH） is produced, which is not completely used during the assimilation of CO2, Nitrate reduc- tion in the leaf represents an additional sink for NADPH that is not available to ammonium-grown plants. Nitrate and ammonium nutrition may use different pathways for NADPH consumption, which leads to differences in photosynthesis and photorespiration. The morphological （i.e., cell size, mesophyll thickness, and chloroplast volume） and enzymic （i.e., ribulose-1,5-bisphosphate carboxylase/oxygenase （Rubisco）, phosphoenolpyruvate carboxylase （PEPCase）, and glutamine synthetase/glutamate synthetase （GS/GOGAT）） differences that develop when plants are treated with either nitrate or ammonium nitrogen forms are related to photosynthesis and photorespiration. The differences in photorespiration rate for plants treated with nitrate or ammonium are related to the conversion of citrate to 2-oxoglutarate （2-OG） and photorespiratory CO2 refixation.

关键词： ammonium nitrate nitrogen form photorespiration photosynthesis

Process and performance of DAAF microspheres prepared by continuous integration from synthesis to spherical coating based on microfluidic system

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Defence Technology（防务技术） 2024年第2期32卷 629-643页

作者： Bidong Wu Jiahui Shi Mengsen wei Rui Zhu yi Liu Jinqiang zhou Chongwei An Jingyu Wang School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Shanxi Engineering Technology Research Centre for Ultrafine Powder North University of ChinaTaiyuan 030051China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of DAAF from synthesis to spherical coating was designed and established in this paper, which combined ultrasonic micromixing reaction with microdroplet globular template. In the rapid micromixing stage, the microfluidic mixing technology with ultrasonic was used to synergistically strengthen the uniform and rapid mass transfer mixing reaction between raw materials to ensure the uniformity of DAAF particle nucleation-growth, and to prepare high-quality DAAF crystals with uniform structure and morphology and concentrated particle size distribution. In the microdroplet globular template stage, the microfluidic droplet technology was used to form a droplet globular template with uniform size under the shear action of the continuous phase of the dispersed phase solution containing DAAF particles and binder. The size of the droplet template was controlled by adjusting the flow rate ratio between the continuous phase and the dispersed phase. In the droplet globular template, with the diffusion of the solvent in the dispersed phase droplets, the binder precipitates to coat the DAAF into a ball, forming a DAAF microsphere with high sphericity, narrow particle size distribution and good monodispersity. The problem of discontinuity and DAAF particle suspension in the process was solved, and the coating theory under this process was studied. DAAF was coated with different binder formulations of fluororubber(F2604), nitrocellulose(NC) and NC/glycidyl azide polymer(GAP), and the process verification and evaluation of the system were carried out. The balling effects of large, medium and small droplet templates under different binder formulations were studied. The scanning electron microscope(SEM) results show that the three droplet templates under the three binder formul

关键词： DAAF Micromixing technology Microdroplet technology Synthesis Spherical coating Continuousization

A hybrid technique： intra-arterial catheter-directed thrombolysis following the recanalization of superior mesenteric artery in acute mesenteric ischemia

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Chinese Medical Journal 2013年第7期126卷 1381-1383页

作者： ZHU Jie-chang DAI Xiang-chen FAN Hai-lun FENG zhou ZHANG yi-wei LUO Yu-dong Department of General Surgery General Hospital of Tianjin Medical University Tianjin 300052 China

Acute mesenteric ischemia is a deadly process withoverall mortality rate of 40%. Acute thrombosis of an atherosclerotic lesion with previous partial occlusion isone of the common causes. Peri-operative mortality ofsu... 详细信息

关键词： superior mesenteric artery mesenteric ischemia thrombosis embolectomy angioplasty intra-arterial catheter-directed thrombolysis

Evolution of chemistry and selection technology for DNA-encoded library

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Acta Pharmaceutica Sinica B 2024年第2期14卷 492-516页

作者： Peixiang Ma Shuning Zhang Qianping Huang Yuang Gu Zhi zhou wei Hou wei yi Hongtao Xu Shanghai Key Laboratory of Orthopedic Implants Department of OrthopedicsShanghai Ninth People’s HospitalShanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China Shanghai Institute for Advanced Immunochemical Studies ShanghaiTech UniversityShanghai 201210China Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target&Clinical Pharmacology The NMPA and State Key Laboratory of Respiratory DiseaseGuangzhou Medical UniversityGuangzhou 511436China College of Pharmaceutical Science and Institute of Drug Development&Chemical Biology Zhejiang University of TechnologyHangzhou 310014China

DNA-encoded chemical library(DEL)links the power of amplifiable genetics and the nonself-replicating chemical phenotypes,generating a diverse chemical *** analogy with the biological world,the DEL world can evolve by using a chemical central dogma,wherein DNA replicates using the PCR reactions to amplify the genetic codes,DNA sequencing transcripts the genetic information,and DNA-compatible synthesis translates into chemical ***,DNA-compatible synthesis is the key to expanding the DEL chemical ***,the evolution-driven selection system pushes the chemicals to evolve under the selective pressure,i.e.,desired selection *** this perspective,we summarized recent advances in expanding DEL synthetic toolbox and panning strategies,which will shed light on the drug discovery harnessing in vitro evolution of chemicals via DEL.

关键词： DNA-encoded library Drug discovery High-throughput selection DNA-compatible synthesis In vitro evolution Chemical central dogma