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Asymmetric synthesis of pyrrolo[1,2-a]indoles via organocatalytic[3+2]annulation of substituted 2-vinylindoles with azlactones

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Chinese Chemical Letters 2020年第3期31卷 721-724页

作者： Wulin Yang Hao Wang Zirong Pan zhong Li Weiping Deng Shanghai Key Laboratory of Chemical Biology School of PharmacyEast China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of New Drug Design School of PharmacyEast China University of Science and TechnologyShanghai 200237China Shanghai Collaborative Innovation Center for Biomanufacturing Technology Shanghai 200237China

The chiral phosphoric acid catalyzed asymmetric[3+2]annulation of substituted 2-vinylindoles with azlactones has been *** reaction represented a practical approach for the synthesis of structurally diverse pyrrolo[1,2-a]indoles with two vicinal stereocenters including one tetrasubstituted stereocenter in good yields and good stereoselectivities under mild conditions.

关键词： [3+2]Annulation Azlactones 2-Vinylindoles Asymmetric organocatalysis Pyrrolo[1,2-a]indoles Chiral phosphoric acid

工程机械驾驶员适意驾驶区域的计算机辅助求解

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东北大学学报（自然科学版） 2000年第5期21卷 516-519页

作者：杨英李江张国忠东北大学机械工程与自动化学院辽宁沈阳110006 沈阳正发建筑安装工程公司辽宁沈阳110003

在充分考虑工程机械特点的基础上 ,以人体H点作为司机室设计的基准点 ,把坐姿舒适性、操纵轻便性和视野宽敞性要求与坐姿角相结合 ,建立人体坐姿杆系模型和数学模型·用计算机辅助设计 (CAD)技术 ,开发了求解工程机械驾驶员适宜驾驶位置... 详细信息

在充分考虑工程机械特点的基础上 ,以人体H点作为司机室设计的基准点 ,把坐姿舒适性、操纵轻便性和视野宽敞性要求与坐姿角相结合 ,建立人体坐姿杆系模型和数学模型·用计算机辅助设计 (CAD)技术 ,开发了求解工程机械驾驶员适宜驾驶位置的H点分布系统 ,分别绘制出了中等身材、小身材和大身材驾驶员适宜驾驶位置时H点区域图 ,该区域为驾驶员座椅和司机室内相关设施的合理布置提供了理论根据·

关键词：工程机械驾驶室座椅人体H点 CAD 计算机辅助求解

Well interference evaluation considering complex fracture networks through pressure and rate transient analysis in unconventional reservoirs

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Petroleum Science 2023年第1期20卷 337-349页

作者： Jia-Zheng Qin Qian-Hu zhong Yong Tang Wei Yu Kamy Sepehrnoori State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500SichuanChina The University of Texas at Austin AustinTX78703USA

Severe well interference through complex fracture networks(CFNs)can be observed among multi-well pads in low permeability *** well interference analysis between multi-fractured horizontal wells(MFHWs)is vitally important for reservoir effective *** interference has been historically investigated by pressure transient analysis,while it has shown that rate transient analysis has great potential in well interference ***,the impact of complex fracture networks(CFNs)on rate transient behavior of parent well and child well in unconventional reservoirs is still not *** further investigate,this paper develops an integrated approach combining pressure and rate transient analysis for well interference diagnosis considering *** perform multi-well simulation considering CFNs,non-intrusive embedded discrete fracture model approach was applied for coupling fracture with reservoir *** impact of CFN including natural fractures and frac-hits on pressure and rate transient behavior in multi-well system was *** a logelog plot,interference flow and compound linear flow are two new flow regimes caused by nearby *** both NFs and frac-hits are present in the reservoir,frac-hits have a greater impact on well#1 which contains frac-hits,and NFs have greater impact on well#3 which does not have *** all well producing circumstances,it might be challenging to see divergence during pseudosteady state flow brought on by frac-hits on the logelog ***,when NFs occur,reservoir depletion becomes noticeable in comparison to frac-hits in pressure *** of this integrated approach demonstrates that it works well to characterize the well interference among different multi-fractured horizontal wells in a well *** reservoir evaluation can be acquired based on the new features observed in the novel model,demonstrating the practicability of the proposed *** findings of this study

关键词： Well interference Numerical rate transient analysis Numerical pressure transient analysis Complex fracture networks Embedded discrete fracture model

Novel numerical model to simulate water seepage through segmental gasketed joints of underwater shield tunnels considering the superimposed seepage squeezing effect

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Underground Space 2023年第6期13卷 104-120页

作者： Qixiang Yan Haojia zhong Chuan Zhang Zechang Zhao Yanxin Wen Ping Wang Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 610031China China Railway Eryuan Engineering Group Co. Ltd.Chengdu 610031China

The water leakage through segmental joint gaskets has become a major concern that adversely affects the normal serviceability of underwater shield tunnels throughout the construction and operational ***,it is of great significance to investigate the sealing performances of the joint gaskets,which directly helps evaluate the waterproof capacity of underwater shield *** date,the numerical modeling plays an irreplaceable role in the analysis on the waterproof capacity of the joint ***,conventional methods tend to ignore the self-sealing effect induced by the water seepage pressurization,thus failing to reveal the progressive evolution of the water infiltration process through the joint *** remedy this defect,this paper proposed a novel numerical model to simulate the penetration process of the sealing gasket based on the Python language-enabled secondary programming in the ABAQUS software,which could fully consider the superimposed seepage squeezing *** on the proposed model,the waterproof failure process and the dynamic contact stress of the gasket’s water seepage path subject to excessive hydraulic pressure were thoroughly ***,indoor tests on the waterproof capacity of the gasket were also performed to validate the proposed *** is found that the numerical results from the developed model are consistent with the experimental *** research will contribute to better understanding of the gaskets’hydraulic penetration process and more accurate prediction of the maximum waterproof capacity in underwater shield tunnels.

关键词： Underwater shield tunnel Hydraulic pressure Gasketed joint Water leakage Sealing performance Finite element method

Research of multi-path routing based on network coding in space information networks

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Chinese Journal of Aeronautics 2014年第3期27卷 663-669页

作者： Yu Geng zhong Congjiu Lan Xiaoyu Zhang Chi Wei Lina Liu Yansong Department of Civil Aviation Shenyang Aerospace University

A multi-path routing algorithm based on network coding is proposed for combating long propagation delay and high bit error rate of space information networks. On the basis of traditional multi-path routing, the algorithm uses a random linear network coding strategy to code data pack- ets. Code number is determined by the next hop link status and the number of current received packets sent by the upstream node together. The algorithm improves retransmission and cache mechanisms through using redundancy caused by network coding. Meanwhile, the algorithm also adopts the flow distribution strategy based on time delay to balance network load. Simulation results show that the proposed routing algorithm can effectively improve packet delivery rate, reduce packet delay, and enhance network performance.

关键词： Flow distribution Multi-path routing Network coding Retransmission Space information networks

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哈尔滨制药六厂变电所扩建改造设计研究

哈尔滨工业大学学报 2005年第4期37卷 459-462页

作者：郑文忠刘铁王英哈尔滨工业大学土木工程学院黑龙江哈尔滨150090

扼要介绍了哈尔滨制药六厂变电所扩建改造工程的概况,阐述了本工程上部结构体系选择与设计、基础型式选择与设计、施工方案与施工验算等方面的内容.可供建造同类工程时参考.

关键词：套建预应力混凝土框架结构桩钢桁架托换

Effect of electro-acupuncture combined with psychological intervention on mental symptoms and P50 of auditory evoked potential in patients with internet addiction disorder

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Journal of Traditional Chinese Medicine 2017年第1期37卷 43-48页

作者： Li Hui Jin Rongjiang Yuan Kezhu Zheng Bo Zheng zhong Luo ying Ye Hua Huang Bingjie Zhu Tianmin School of Medicine Chengdu UniversityChengdu 610106China College of Health and Rehabilitation Chengdu University of Traditional Chinese MedicineChengdu 610075China West China School of Medicine Sichuan UniversityChengdu 610041China Mental Health Center West China Hospital of Sichuan UniversityChencjdu 610041China Rehabilitation Center of Sichuan Limbs Disability Chengdu 610021China

OBJECTIVE: To observe the therapeutic effects of electro-acupuncture(EA) combined with psychological intervention on the symptom of somzatization or obsession and mental symptom of depression or anxiety and P50 of Auditory Evoked Potential(AEP) on internet addiction disorder(IAD).METHODS: One hundred and twenty cases of IAD were randomly divided into an EA group, a psycho-intervention(PI) group and a comprehensive therapy(EA plus PI) group. Patients in the EA group were treated with EA. Patients in the PI group were treated with cognition and behavior therapy. Patients in the EA plus PI group were treated with electro-acupuncture plus psychological intervention. Scores of IAD, scores of the symptom checklist90(SCL-90), latency and amplitude of P50 of AEP were measured before and after ***: The scores of IAD after treatment significantly decreased in all groups(P < 0.05), and thescores of IAD in the EA plus PI group were significantly lower than those in the other two groups(P < 0.05). The scores of SCL-90 assembled and each factor after treatment in the EA plus PI group significantly decreased(P < 0.05). After treatment in the EA plus PI group, the amplitude distance of S1P50 and S2P50(S1-S2) significantly increased(P < 0.05).CONCLUSION: EA combined with PI could relieve the mental symptoms of IAD patients, and the mechanism is possibly related to the increase of cerebrum sense perception gating function.

关键词： Internet addiction disorder Electroacupuncture Psychological intervention Obsessive behavior Evoked potentials

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一种基于球坐标系的四站三维时差定位算法

现代防御技术 2011年第1期39卷 133-137页

作者：陈双赵宏忠唐山科技职业技术学院河北唐山063000 北京无线电测量研究所北京100854

提出了一种在球坐标系下的无源时差定位算法,该算法解决了参变量法中难于解决的模糊和无解问题,计算量小,定位结果可信。当布站接近平面时,本算法可独立进行定位,当站址高度差较大时本算法可以与参变量法相配合解决模糊和无解问题,适合... 详细信息

提出了一种在球坐标系下的无源时差定位算法,该算法解决了参变量法中难于解决的模糊和无解问题,计算量小,定位结果可信。当布站接近平面时,本算法可独立进行定位,当站址高度差较大时本算法可以与参变量法相配合解决模糊和无解问题,适合于工程应用。

关键词：时差定位球坐标系模糊和无解

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Optimization of the resonant frequency servo loop technique in the resonator micro optic gyro

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第11期12卷 942-950页

作者： Yang REN zhong-he JIN Yan CHEN Hui-lian MA Department of Information Science ＆ Electronic Engineering Zhejiang University Hangzhou 310027 China

Proportional integrator (PI) is always adopted in the resonant frequency servo loop in a resonator micro optic gyro (RMOG). The oscillation phenomenon is observed when adjusting the loop gain surpassing a threshold. This phenomenon limits system performance on step response speed and residual error. Based on the experiment system, a simulation model was set up. Further analysis shows that the threshold gain is related to the system loop filter setting and the loop delay. The traditional PI frequency servo loop technique in the RMOG system cannot keep up with the environment's disturbance quickly enough, which leads to a large residual error. A compensating method is proposed to optimize the tracking performance, solve the oscillation problem, and speed up the system response. Simulation and experiment results show that the compensated system is superior in performance. It has less residual error in the stable state and is 10 times quicker than the uncompensated system on the step response.

关键词： Resonator micro optic gyro (RMOG) Resonance frequency servo loop Phase compensating method