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Stiffness of Postural Alignment System Based on 3-Axis Actuators for Large Aircraft Components

Chinese Journal of Mechanical Engineering 2010年第4期23卷 524-531页

作者： guo zhimin JIANG Junxia KE Yinglin The State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Aircraft digital flexible assembly fixture and technologies are widely used in developed countries, while the traditional jig-based assembly mode is still used in China. The application study of aircraft digital flexible assembly system is just beginning in our country recently. To meet the requirements of automated posture alignment and join in digital assembly system for large aircraft components, a novel fitting fixture called 3-axis actuator is developed. On the basis of the actuators, three kinds of posture alignment system for large aircraft components are proposed, including the non-redundant system, the redundant actuating system, and the redundant leg system, and their constitutions and properties are introduced. Through deriving the feeding transmission stiffness model of single actuator and analyzing the inverse kinematics of these systems, the relationship between the external force and the changes of position and orientation of large aircraft component is obtained, and then the postural alignment stiffness models are established. With the method mentioned above, the postural alignment stiffness of three systems is computed by using the algebraic formulate, and the results show that redundant properties can increase system＇s postural alignment stiffness. As an example, a optimized layout of the assembly system for a given model of aircraft is developed, the results of application show that the layout has many advantages, such as high accuracy, stiffness, stability, reliability, efficiency and flexible, which can satisfy the requirement of aircraft digital assembly system well. The proposed study of postural alignment stiffness for different systems can supply the theoretic support for the optimization layout design of aircraft digital assembly system, and contribute to evaluate the system working performance of systems.

关键词： 3-axis actuator large aircraft component redundant postural alignment stiffness posture-holding

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Anomaly detection in smart grid based on encoder-decoder framework with recurrent neural network

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The Journal of China Universities of Posts and Telecommunications 2017年第6期24卷 67-73页

作者： Zheng Fengming Li Shufang guo zhimin Wu Bo Tian Shiming Pan Mingming Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing 100876 China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876 China State Grid Henan Electric Power Research Institute Zhengzhou 450052 China China Electric Power Research Institute Beijing 100192 China

Anomaly detection in smart grid is critical to enhance the reliability of power systems. Excessive manpower has to be involved in analyzing the measurement data collected from intelligent motoring devices while performance of anomaly detection is still not satisfactory. This is mainly because the inherent spatio-temporality and multi-dimensionality of the measurement data cannot be easily captured. In this paper, we propose an anomaly detection model based on encoder-decoder framework with recurrent neural network （RNN）. In the model, an input time series is reconstructed and an anomaly can be detected by an unexpected high reconstruction error. Both Manhattan distance and the edit distance are used to evaluate the difference between an input time series and its reconstructed one. Finally, we validate the proposed model by using power demand data from University of California, Riverside （UCR） time series classification archive and IEEE 39 bus system simulation data. Results from the analysis demonstrate that the proposed encoder-decoder framework is able to successfully capture anomalies with a precision higher than 95%.

关键词： smart grid encoder-decoder framework anomaly detection time series mining

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Raising the Speed Limit of Axial Piston Pumps by Optimizing the Suction Duct

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 271-280页

作者： Yu Fang Junhui Zhang Bing Xu Zebing Mao Changming Li Changsheng Huang Fei Lyu zhimin guo State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310027China Department of Engineering Science and Mechanics Shibaura Institute of TechnologyTokyoJapan Hangzhou Optimax Tech Co. LtdHangzhouChina Linde Hydraulics(China)Co. LtdWeifang261000China

The maximum delivery pressure and the maximum rotational speed determine the power density of axial piston ***,increasing the speed beyond the limit always accompanies cavitation,leading to the decrease of the volumetric *** pressure loss in the suction duct is considered a significant reason for the ***,this paper proposes a methodology to optimize the shape of the suction duct aiming at reducing the intensity of cavitation and increasing the speed *** first,a computational fluid dynamics(CFD)model based on the full cavitation model(FCM)is developed to simulate the fluid field of the axial piston pump and a test rig is set to validate the *** the topology optimization is conducted for obtaining the minimum pressure loss in the suc-tion *** the original suction duct with the optimized one in the simulation model,the pressure loss in the suction duct gets considerable reduction,which eases the cavitation intensity a *** simulation results prove that the speed limit can increase under several different inlet pressures.

关键词： Axial piston pump Speed limit Topology optimization Suction duct Cavitation

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Sulfur deposition in sour gas reservoirs:laboratory and simulation study

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Petroleum Science 2009年第4期6卷 405-414页

作者： Xiao guo zhimin Du Xuefeng Yang Yong Zhang Dekui Fu SW Petr Univ State Key Lab Oil & Gas Reservoir Geol & Exploita Chengdu 610500 Sichuan Peoples R China

Sulfur deposition in the formation, induced by a reduction in the solubility of the sulfur in the gas phase, may significantly reduce the inflow performance of sour gas wells and some wells in sour gas reservoirs have even become completely plugged with deposited sulfur within several months. Accurate prediction and effective management of sulfur deposition are crucial to the economic viability of sour gas reservoirs. In this paper, a dynamic flow experiment was carried out to investigate formation damage resulting from sulfur deposition using an improved experimental method. The core sample was extracted from the producing interval of the LG2 well, LG gas field in the Sichuan Basin. The experimental temperature was 26 °C and the initial pressure was 19 MPa. The displacement pressure continuously decreased from 19 to 10 MPa, and the depletion process lasted 15 days. Then the core was removed and dried. The core mass and core permeability were measured before and after experiments. Experimental results indicated that the core mass increased from 48.372 g before experiment to 48.386 g afterwards, while the core permeability reduced from 0.726 to 0.608 md during the experiment. Then the core was analyzed with a scanning electron microscope (SEM) and energy-dispersive X-ray mapping. The deposition pattern and micro-distribution of elemental sulfur was observed and the deposited elemental sulfur distributed as a film around the pore surface.

关键词： Sour gas reservoir sulfur deposition experiment numerical simulation formation damage

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“优师专项”的政策优势、实施挑战与优化策略

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教育发展研究 2022年第2期42卷 9-17页

作者：郭志慜华东师范大学教育学部上海200062

"优师专项"是强化中西部欠发达地区教师定向培养的重要举措,该计划有助于实现国家地方多元主体协同育人、乡村教师队伍结构优化、区域教育发展更加均衡、教育贫困治理精准有效等愿景。然而,"优师专项"在实施推进中还面临人事管理制度改... 详细信息

"优师专项"是强化中西部欠发达地区教师定向培养的重要举措,该计划有助于实现国家地方多元主体协同育人、乡村教师队伍结构优化、区域教育发展更加均衡、教育贫困治理精准有效等愿景。然而,"优师专项"在实施推进中还面临人事管理制度改革、培养院校规模扩容、招生计划布局调整、乡村教师职业发展等诸多挑战。为提升政策效果,本文建议应进一步完善教师人事制度,建立良性乡村教师流动机制;扩充地方培养单位,设置梯度化的招生院校结构;扩大政策辐射范围,实现教师供求结构合理匹配;加强教育支持力度,提升乡村教师的职业吸引力。由此,深化教师队伍供给改革,助推乡村教育振兴发展。

关键词：优师专项乡村教师政策优势实施挑战优化策略

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Expressions of G2A and OGR1 in peripheral blood cells of patients with hypoxia-induced pulmonary hypertension

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Discussion of Clinical Cases 2017年第3期4卷 16-20页

作者： Min Wu Jingping Yang Xiyuan Xu zhimin guo Baoying Bu The Third Affiliated Hospital of Inner Mongolia Medical University Baogang HospitalBaotouChina

Objective: To detect the expression changes of proton-sensing receptor G protein-coupled receptor 2A (G2A) and ovarian cancer G protein-coupled receptors 1 (OGR1) in human peripheral blood cells of patients with hypoxia-induced pulmonary hypertension (HPH). Methods: Thirty-one patients with HPH were enrolled for IPH group, 16 males and 15 females, aged (65.19 ± 5.86) years;and 30 healthy people were enrolled for control group (NC group), 15 males and 15 females, aged (63.47 ± 6.16) years. The peripheral blood samples were collected and the mRNA expressions of G2A and OGR1 were determined by using real-time fluorescent quantitative PCR. The pulmonary arterial pressure (PAP) of HPH group was detected with echocardiography for the analysis of blood gas and pulmonary function testing. Human peripheral blood was collected to detect the mRNA levels of G2A, OGR1 and the serum levels of tumor necrosis factor-α (TNF-α). Results: PaCO2 was increased significantly in HPH group than that in NC group (p < .05). The percentage of forced expiratory volume in 1 s in predicted value (FEV1 pro%) and the ratio of FEV1/forced vital capacity (FVC) in HPH group were significant lower than those in NC group (p < .05). The expressions of peripheral blood G2A mRNA and TNF-α in HPH group were increased dramatically than those in NC group (p < .05). The expressions of OGR1 mRNA in peripheral blood had no difference between HPH group and NC group. The expressions of G2A mRNA and TNF-α in HPH group were positively related to pulmonary artery pressure significantly. Conclusions: The expression of proton-sensing receptor G2A and the level of TNF-α were increased in peripheral blood cells of patients with pulmonary hypertension. The expressions of TNF-α and G2A had positive correlations with pulmonary artery pressure.

关键词： Hypoxia-induced pulmonary hypertension Proton-sensing receptor G2A OGR1 TNF-α

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Analysis and Comparison of the Effect of Preserving Spontaneous Breathing Without Intubation and Endotracheal Intubation with One Lung Ventilation in Single-hole Thoracoscopic Bulla Suture

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Journal of Clinical and Nursing Research 2022年第5期6卷 99-105页

作者： Hefei Li Pei Liu Yanhong Shang zhimin guo Biao Zhang Kuo Xiao Qiang guo Xianyi Liu Department of Thoracic Surgery Affiliated Hospital of Hebei UniversityBaoding 071000China Department of Medical Oncology Affiliated Hospital of Hebei UniversityBaoding 071000China Department of General Surgery Affiliated Hospital of Hebei UniversityBaoding 071000China

Objective:To explore the situation of patients and the compare the effect between two methods,which are preserving spontaneous breathing without intubation and endotracheal intubation with one lung ventilation in the single-hole thoracoscopic bulla ***:42 patients who received single-hole thoracoscopic pulmonary bullae suture in our hospital from January 2020 to December 2021 were selected as the study subjects,including 19 patients who underwent endotracheal intubation and one lung ventilation as the control group and 23 patients who underwent single-hole thoracoscopic pulmonary bullae suture without intubation as the study *** relevant indexes,postoperative general conditions,complications and pneumothorax recurrence of the two groups were analyzed and ***:In the control group,the scores of anesthesia time(points),resuscitation time(points),surgical visual field score(points),surgical time(points),and surgical bleeding volume(points)were 20.8±4.6,19.9±7.9,1.7±0.5,44.9±7.9,and 11.4±2.4 *** the study group,the scores of anesthesia time(points),resuscitation time(points),surgical visual field score(points),surgical time(points),and scores of surgical bleeding(points)were 17.9±4.3,15.4±3.4,1.9±0.4,48.4±7.1,10.9±2.2,*** was no statistical difference in surgical visual field score,surgical time and surgical bleeding whereas there was a statistical difference between anesthesia time and resuscitation *** the control group after operation,VAS score at 6 hours after operation,SaO_(2)(%)after operation,PaCO_(2)(mmHg)after operation,drainage volume(ML)after operation,feeding time(H)after operation,retention time of thoracic tube after operation(H),WBC(109)on the first day after operation,hospitalization time(d),and total hospitalization cost(RMB 1000)were 2.1±0.7,98.2±1.4,42.4±4.9,139.1±23.1,6.9±1.6,37.1±5.4,7.9±2.1,6.6±1.3,and 2.6±0.3 *** for the study group,the VAS score at 6 hours after operation,SaO_

关键词： Spontaneous breathing One lung ventilation Single-hole thoracoscopy

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Provision of Human Resources for Water Resources and Hydropower Projects——A case of CGGC

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当代经理人(中旬刊) 2006年第7期 178-179页

作者： guo zhimin (CGGC Staff & Workers Training and Education Center, Yichang 443000,China)

Human recourses provision and management plays an important role in constructing water recourses and hydropower projects, CGGC is a super huge enterprise which mainly conducts water resources and hydropower projects, how does its personnel provision and management work, this paper is about its situation of the staff and workers, its human recourses provision and management.

关键词： human recourses provision personnel management water recourses and hydropower projects

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基于POGO柱三点支撑的飞机大部件调姿方法

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航空学报 2009年第7期30卷 1319-1324页

作者：郭志敏蒋君侠柯映林浙江大学流体传动及控制国家重点实验室浙江杭州310027

针对飞机数字化装配中大部件调姿与对接问题,设计了一种精密三坐标POGO柱,在此基础之上提出了一种基于三坐标POGO柱三点支撑的姿态调整方法。对基于POGO柱的调姿特性进行了分析,掌握了姿态可叠加特性和POGO柱受力状态的可叠加特性,由此... 详细信息

针对飞机数字化装配中大部件调姿与对接问题,设计了一种精密三坐标POGO柱,在此基础之上提出了一种基于三坐标POGO柱三点支撑的姿态调整方法。对基于POGO柱的调姿特性进行了分析,掌握了姿态可叠加特性和POGO柱受力状态的可叠加特性,由此得到了大部件调姿过程中三坐标POGO柱受力变形的计算方法,并给出POGO柱变形引起大部件姿态误差的数学模型,为控制系统实施调姿过程误差补偿提供了依据。仿真分析和实验研究表明基于3个POGO柱的大部件调姿方法具有稳定、可靠、高效的优点,通过简单的重组可以推广到四点支撑以便适应各类大型部件姿态调整的需要。

关键词：三坐标POGO柱调姿大部件重构柔性装配

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退化马尾松群落恢复与重建途径的研究

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林业科技 2000年第6期25卷 1-3页

作者：郭志民福建省南安市水土保持试验站南安市362300

对不同退化马尾松群落的恢复与重建进行试验研究的结果表明 :不同退化马尾松群落通过封禁治理 ,其自然恢复能力不同。植被盖度大于 30 %以上的退化群落可以得到不同程度的恢复 ,低于 30 %的仅通过封禁难以恢复 ;较严重退化马尾松群落通... 详细信息

对不同退化马尾松群落的恢复与重建进行试验研究的结果表明 :不同退化马尾松群落通过封禁治理 ,其自然恢复能力不同。植被盖度大于 30 %以上的退化群落可以得到不同程度的恢复 ,低于 30 %的仅通过封禁难以恢复 ;较严重退化马尾松群落通过封禁、施肥和抚育管理措施 ,可以得到恢复 ;严重退化马尾松群落要通过挖大穴、施基肥、进行多树种多层次混交。

关键词：退化马尾松群落群落恢复群落重建封禁治理

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