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Walking Control of a Semi-Passive Biped Robot based on Repetitive Control Algorithm 36

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Walking Control of a Semi-Passive Biped Robot based on Repet...

Technology and application of pressure relief and permeability increase by jointly drilling and slotting coal

第36届中国控制会议

作者： Yali Zhou qizhi zhang School of Automation Beijing Information Science ＆ Technology University

ISBN: (纸本)9781538629185

The walking control on level ground of a semi-passive biped robot is ***,the dynamic equation of the swing phase is derived using the Euler-Lagrange method,and the transition model at heelstrike collision is derived based on conservation of angular momentum and impulse-momentum *** a toe-off impulse is applied to the stance leg just before *** initial impulse value is obtained by solving the linearized equations during the swinging *** on the initial value,the repetitive control（RC） algorithm is used to make the value of the toe-off impulse more ***,computer simulations are carried out to verify the effectiveness of the presented *** results show that the convergence rate of the RC algorithm is superior to that of the ILC algorithm,and the biped robot can walk stably on level ***,all the eigenvalues of the Jacobian matrix are located inside the unit circle,so the stability condition of the biped robot system is satisfied.

关键词： Biped robot Semi-passive walking Impulsive push Repetitive control algorithm

来源： cnki会议评论

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International Journal of Mining Science and Technology 2012年第4期22卷 545-551页

作者： Lin Baiquan zhang Jianguo Shen Chunming zhang qizhi Sun Chen State Key Laboratory of Coal Resources and Mine Safety China University of Mining&TechnologyXuzhou 221008China School of Safety Engineering China University of Mining 6"TechnologyXuzhou 221008China Zhongping Energy Chemical Group Pingdingshan 467000China

Difficulties with soft coal seams having a high gas content and high stress levels can be addressed by a technology of pressure relief and permeability *** the seam by auxiliary drilling with a water jet that breaks the coal and slots the coal seam during the process of retreat drilling achieves pressure relief and permeability *** efficiency of gas extraction from a field test,high gas coal seam was *** the theory of pressure relief and permeability increase required analyzing the characteristics of the double power slotting process and the effects of coal pressure relief and permeability *** influence of confining pressure on coal physical properties was examined by using FLAC3D software code to simulate changes of coal stress within the tool destruction *** double power joint drilling method was *** experiments were performed and the effects are *** research shows that there is an ''islanding effect'' in front of the joint double power drill and slotting *** failure strength of the coal seam is substantially reduced within the tool destruction *** depths are increased by 72% and the diameter of the borehole is increased by 30%.The amount of powdered coal extracted from the drill head increases by 17 times when using the new method.A 30 day total flow measurement from the double power drilled and slotted bores showed that gas extraction increased by 1.3 times compared to the standard drilled *** concentrations increased from 30% to 60% and were more stable so the overall extraction efficiency increased by a factor of two times.

关键词： Collaborative drillingDouble powerSlottingPressure relief and permeability increase

Induced drill-spray during hydraulic slotting of a coal seam and its influence on gas extraction

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International Journal of Mining Science and Technology 2012年第6期22卷 785-791页

作者： Shen Chunming Lin Baiquan zhang qizhi Yang Wei zhang Lianjun School of Safety Engineering China University of Mining & Technology Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and Technology

Hydraulic slotting can induce drill spray in a gassy,low permeability coal *** then influences subsequent gas *** paper describes the drill spray phenomenon from a mechanical perspective and analyzes the effects of water jet damage during slotting.A simulation of the stresses around the drill hole and slot was prepared using FLAC-3D *** helps explain the induction of drill spray during hydraulic *** stress concentration around the bore increases as the diameter of the hole *** the hole enlarges the variation in stress also increases,which introduces an instability into the *** allows easy breaking and removal of the *** of the coal structure by the water jet is the major factor causing drill *** stored as either strain or gas pressure is released by the water jet and this causes the coal to fracture and be expelled from the *** tests showed the effect on gas extraction after slotting with drill *** concentration of gas increases after *** to conventional techniques,the hydraulic slotted bore gives a gas concentration three times higher and has an effective range twice as *** makes the gas extraction process more efficient and allows reduced construction effort.

关键词： Slotted Drill-spray Water jet Pressure relief and permeability increase Gas extraction

Application of pressure relief and permeability increased by slotting a coal seam with a rotary type cutter working across rock layers

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International Journal of Mining Science and Technology 2012年第4期22卷 533-538页

作者： Shen Chunming Lin Baiquan Meng Fanwei zhang qizhi Zhai Cheng State Key Laboratory of Coal Resources and Mine Safety China University of Mining&TechnologyXuzhou 221008ChinaSchool of Safety EngineeringChina University of Mining&TechnologyXuzhou 221008China

Pressure relief to increase permeability significantly improves gas extraction efficiency from coal seams. In this paper we report results from simulations using FLAC3D code to analyze changes in coal displace- ment and stress after special drill slots were formed. We investigated the mechanism of pressure relief and permeability increase in a high-gas and low-permeability coal seam through the modeling of gas flow. This allows the development of the technology. Slotting across rock layers in the coal seam with a rotary type cutter was then applied in the field. The results show that pressure relief and permeability increases from slotting the coal seam can increase the transport and the fracture of the coal. This expands the range of pressure relief from the drilling and increases the exposed area of the seam. The total quan- tity of gas extracted from slotted bore holes was three times that seen with ordinary drilling. The concen- tration of gas extracted from the slotted drills was from two to three times that seen using ordinary drills. The gas flow was stable at 80%. Improved permeability and more efficient gas extraction are the result of the slotting. The roadway development rate is increased by 30-50% after gas drainage. This technology diminishes the lag between longwall production and roadway development and effectively prevents coal and gas outburst, which offers the Drosnect of broad anDlication.

关键词： Penetrate layerSlottedPressure relief and permeability increasePermeabilityGas extraction

Present Situation and Problems Analysis of Waterproof and Seal of Prefabricated Building Exterior Wall

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Frontiers Research of Architecture and Engineering 2018年第1期1卷 8-11页

作者： qizhi zhang Huanghuai University ZhumadianHenan463000China

With the continuous development and progress of China's social economy,the construction speed of our construction industry is also *** with the traditional cast-in-place reinforced concrete and masonry building,it has been unable to meet the requirements of the construction industry and the development of the *** the prefabricated building has the advantages of fast speed,water saving,land saving,noise reduction,material saving and energy saving in *** with traditional buildings,the prefabricated building is more energy efficient and ***,the new type of precast assembly architecture is constantly highlighted and has become the mainstream of the development of the future construction ***,the technology started late in China,and the immature technology and imperfect supporting standards led to slow progress and even stagnation in China's construction *** the analysis of the present situation and problems of the waterproof and sealing of the prefabricated building exterior walls,the suggestions for the healthy development of the construction industry in China are put forward in time.

关键词： Prefabricated housing Waterproofing on the exterior wall Seal Problem

A CLOSED FORM SOLUTION OF STRESS INTENSITY FACTORS FOR THREE DIMENSIONAL FINITE BODIES WITH ECCENTRIC CRACKS

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Chinese Journal of Aeronautics 1990年第4期5卷 246-257页

作者： Wang qizhi, zhang Xing and Ren BingyiBeijing University of Aeronautics and Astronautics

In this paper, a new analytical-engineering method of closed form solution about stress intensity factors for three dimensional finite bodies with eccentric cracks is derived by means of energy release rate method. The results of stress intensity factors can be obtained. The results provided ir this method are in nice agreement with those of the famous alternating method by which only special cases can be solved.

关键词： FORM A CLOSED FORM SOLUTION OF STRESS INTENSITY FACTORS FOR THREE DIMENSIONAL FINITE BODIES WITH ECCENTRIC CRACKS

Small interfering RNA delivery to the neurons near the amyloid plaques for improved treatment of Alzheimer’s disease

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Acta Pharmaceutica Sinica B 2019年第3期9卷 590-603页

作者： Qian Guo Xiaoyao Zheng Peng Yang Xiaoying Pang Kang Qian Pengzhen Wang Shuting Xu Dongyu Sheng Liuchang Wang Jinxu Cao Wei Lu qizhi zhang Xinguo Jiang Key Laboratory of Smart Drug Delivery Ministry of Education & State Key Laboratory of Molecular Engineering of Polymers School of Pharmacy Fudan University

Gene therapy represents a promising treatment for the Alzheimer’s disease(AD). However,gene delivery specific to brain lesions through systemic administration remains big challenge. In our previous work, we have developed an siRNA nanocomplex able to be specifically delivered to the amyloid plaques through surface modification with both CGN peptide for the blood–brain barrier(BBB)penetration and QSH peptide for β-amyloid binding. But, whether the as-designed nanocomplex could indeed improve the gene accumulation in the impaired neuron cells and ameliorate AD-associated symptoms remains further study. Herein, we prepared the nanocomplexes with an siRNA against β-site amyloid precursor protein-cleaving enzyme 1(BACE1), the rate-limiting enzyme of Aβ production, as the therapeutic siRNA of AD. The nanocomplexes exhibited high distribution in the Aβ deposits-enriched hippocampus, especially in the neurons near the amyloid plaques after intravenous administration. In APP/PS1 transgenic mice, the nanocomplexes down-regulated BACE1 in both mRNA and protein levels,as well as Aβ and amyloid plaques to the level of wild-type mice. Moreover, the nanocomplexes significantly increased the level of synaptophysin and rescued memory loss of the AD transgenic mice without hematological or histological toxicity. Taken together, this work presented direct evidences that the design of precise gene delivery to the AD lesions markedly improves the therapeutic outcome.

关键词： siRNA delivery Neurons Amyloid plaques BACE1 gene Alzheimer’s disease

Multidimensional autophagy nano-regulator boosts Alzheimer's disease treatment by improving both extra/intraneuronal homeostasis

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1380-1399页

作者： Yixian Li Peng Yang Ran Meng Shuting Xu Lingling Zhou Kang Qian Pengzhen Wang Yunlong Cheng Dongyu Sheng Minjun Xu Tianying Wang Jing Wu Jinxu Cao qizhi zhang Key Laboratory of Smart Drug Delivery Ministry of EducationSchool of PharmacyFudan UniversityShanghai 201203China

Intraneuronal dysproteostasis and extraneuronal microenvironmental abnormalities in Alzheimer’s disease(AD)collectively culminate in neuronal *** the context of AD,autophagy dysfunction,a multi-link obstacle involving autophagy downregulation and lysosome defects in neurons/microglia is highly implicated in intra/extraneuronal pathological ***,multidimensional autophagy regulation strategies co-manipulating“autophagy induction”and“lysosome degradation”in dual targets(neuron and microglia)are more reliable for AD ***,we designed an RP-1 peptide-modified reactive oxygen species(ROS)-responsive micelles(RT-NM)loading rapamycin or gypenoside *** by RP-1 peptide,the ligand of receptor for advanced glycation end products(RAGE),RT-NM efficiently targeted neurons and microglia in AD-affected *** nanocombination therapy activated the whole autophagy-lysosome pathway by autophagy induction(rapamycin)and lysosome improvement(gypenoside XVII),thus enhancing autophagic degradation of neurotoxic aggregates and inflammasomes,and promoting Aβ ***,it decreased aberrant protein burden,alleviated neuroinflammation,and eventually ameliorated memory defects in 3×Tg-AD transgenic *** research developed a multidimensional autophagy nano-regulator to boost the efficacy of autophagy-centered AD therapy.

关键词： Autophagy-lysosome pathway Alzheimer’s disease Proteostasis Neuroinflammation Multi-target therapy Rapamycin Gypenoside XVII Cascade dual-targeting

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一个先进的教育理念--谈大学文化素质教育

中国高教研究 2010年第7期 3-4页

作者：张岂之清华大学特聘教授北京100084

一、对大学文化素质教育的再认识我国进入改革开放新的历史时期．提出了反映我国民族特色和人的全面发展（德、智、体、美）内在要求的先进教育理念——素质教育。即将颁布的《国家中长期教育改革和发展规划纲要（2010—2020年）》中提... 详细信息

一、对大学文化素质教育的再认识我国进入改革开放新的历史时期．提出了反映我国民族特色和人的全面发展（德、智、体、美）内在要求的先进教育理念——素质教育。即将颁布的《国家中长期教育改革和发展规划纲要（2010—2020年）》中提出“坚持以人为本．推进素质教育是教育改革发展的战略主题”。

关键词：文化素质教育教育理念大学人的全面发展发展规划纲要教育改革民族特色改革开放