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Analyses of environmental impacts of underground coal mining in an arid region using remote sensing and GIS

Journal of Coal Science & Engineering(China) 2011年第4期17卷 363-371页

作者： bian Zheng-fu ZHANG Hai-xia LEI Shao-gang Institute of Land Resources China University of Mining and Technology Xuzhou 221008 China No.2 Survey Group National Bureau of Surveying and Mapping Xi＇an 710054 China

The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM＋ images with no cloud cover from July/August in different years （1990, 1995, 2000 and 2005） were used to analyze the change in various land environmental factors over time. The results show that while mining activity initially had a marked adverse impact on the environment, mine rehabilitation measures have also subsequently played a great role in improving vegetation cover and controlling land desertification and loss of water and soil. The effect of coal mining on vegetation cover is dependent upon the soil type and natural indigenous flora. Results of this investigation imply that mining activity has a greater effect on the vegetation of loess areas than at sandy sites. Although local vegetation coverage was improved by planting in the mining area, the total area of land affected by desertification still in- creased from 26.81% in 1990 when large-scale mine construction was introduced, to 46.79% in 1995. With continuous efforts at rehabilitation, the vegetation cover in the Shendong coal mining area was increasing, and loss of water and soil were effec- tively controlled since 1995. Subsequently, the total area of extreme desertification decreased to 23.24% in 2000 and further to 18.68% in 2005. The total area affected by severe loss of water and soil also decreased since the early 1990＇s （70.61% in 1990, 71.43% in 1995）, to 43.64% in 2000 and 34.93% in 2005, respectively.

关键词： environmental impact land use change arid environment land desertification

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Torsional static and vibration analysis of functionally graded nanotube with bi-Helmholtz kernel based stress-driven nonlocal integral model

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Applied Mathematics and Mechanics(English Edition) 2021年第3期42卷 425-440页

作者： Peiliang bian Hai QING State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A torsional static and free vibration analysis of the functionally graded nanotube(FGNT)composed of two materials varying continuously according to the power-law along the radial direction is performed using the bi-Helmholtz kernel based stress-driven nonlocal integral *** differential governing equation and boundary conditions are deduced on the basis of Hamilton’s principle,and the constitutive relationship is expressed as an integral equation with the bi-Helmholtz *** nominal variables are introduced to simplify the differential governing equation,integral constitutive equation,and boundary *** than transforming the constitutive equation from integral to differential forms,the Laplace transformation is used directly to solve the integro-differential *** explicit expression for nominal torsional rotation and torque contains four unknown constants,which can be determined with the help of two boundary conditions and two extra constraints from the integral constitutive relation.A few benchmarked examples are solved to illustrate the nonlocal influence on the static torsion of a clamped-clamped(CC)FGNT under torsional constraints and a clamped-free(CF)FGNT under concentrated and uniformly distributed torques as well as the torsional free vibration of an FGNT under different boundary conditions.

关键词： integro-differential equation bi-Helmholtz kernel stress-driven nonlocal integral model Laplace transform technique free vibration

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Effects of specific surface area of metallic nickel particles on carbon deposition kinetics

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 226-235页

作者： Zhi-yuan Chen Liu-zhen bian Zi-you Yu Li-jun Wang fu-shen Li Kuo-Chih Chou Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Department of Materials Science and Engineering Delft University of Technology State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Materials Science and Engineering University of Science and Technology Beijing

Carbon deposition on nickel powders in methane involves three stages in different reaction temperature ranges. Temperature programing oxidation test and Raman spectrum results indicated the formation of complex and ordered carbon structures at high deposition temperatures. The values of I（D）/I（G） of the deposited carbon reached 1.86, 1.30, and 1.22 in the first, second, and third stages, respectively. The structure of carbon in the second stage was similar to that in the third stage. Carbon deposited in the first stage rarely contained homogeneous pyrolytic deposit layers. A kinetic model was developed to analyze the carbon deposition behavior in the first stage. The rate-determining step of the first stage is supposed to be interfacial reaction. Based on the investigation of carbon deposition kinetics on nickel powders from different resources, carbon deposition rate is suggested to have a linear relation with the square of specific surface area of nickel particles.

关键词： metallic nickel carbon deposition coking specific surface area methane kinetics

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Calcium silicate accelerates cutaneous wound healing with enhanced re-epithelialization through EGF/EGFR/ERK-mediated promotion of epidermal stem cell functions

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Burns & Trauma 2021年第1期9卷 184-195页

作者： Bingmin Li Haowen Tang Xiaowei bian Kui Ma Jiang Chang Xiaobing fu Cuiping Zhang Research Center for Tissue Repair and Regeneration affiliated to the Medical Innovation Research Division and Fourth Medical Center of Chinese PLA General Hospital 100048BeijingChina Research Unit of Trauma Care Tissue Repair and RegenerationChinese Academy of Medical Sciences100048BeijingChina Department of Dermatology Fourth Medical Center of Chinese PLA General Hospital100048BeijingChina Faculty of Hepato-Biliary-Pancreatic Surgery Chinese PLA General Hospital100853BeijingChina Shanghai Institute of Ceramics Chinese Academy of Sciences200050ShanghaiChina

Background:Human epidermal stem cells(hESCs)play an important role in re-epithelialization and thereby in facilitating wound healing,while an effective way to activate hESCs remains to be *** silicate(CS)is a form of bioceramic that can alter cell behavior and promote tissue ***,we have observed the effect of CS on hESCs and investigated its possible ***:Using a mouse full-thickness skin excision model,we explored the therapeutic effect of CS on wound healing and *** vitro,hESCs were cultured with diluted CS ion extracts(CSIEs),and the proliferation,migration ability and stemness of hESCs were *** effects of CS on the epidermal growth factor(EGF),epidermal growth factor receptor(EGFR)and extracellular signal-related kinase(ERK)signaling pathway were also ***:In vivo,CS accelerated wound healing and *** demonstrated that CS upregulated cytokeratin 19 and integrinβ1 expression,indicating that CS improved hESCs *** vitro studies confirmed that CS improved the biological function of *** the possible mechanism could be due to the activation of the EGF/EGFR/ERK signaling ***:CS can promote re-epithelialization and improve the biological functions of hESCs via activating the EGF/EGFR/ERK signaling pathway.

关键词： bioceramic calcium silicate epidermal stem cells re-epithelialization wounds

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基于SVR-LSTM的人体上肢运动遮挡轨迹补偿方法

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郑州大学学报（理学版） 2025年第1期57卷 1-7页

作者：彭金柱刘涵菲卞英楠郑州大学电气与信息工程学院河南郑州450001 河南交通职业技术学院物流学院河南郑州451460

在人机协作过程中,由于光照条件等环境因素和机器人设备摆放等遮挡原因,导致使用基于视觉的运动捕捉设备对人体运动进行捕捉时时间序列的轨迹数据有缺失,进而导致意图识别不准确,增加了机器人运动的不确定性。因此,提出了一种基于支持... 详细信息

在人机协作过程中,由于光照条件等环境因素和机器人设备摆放等遮挡原因,导致使用基于视觉的运动捕捉设备对人体运动进行捕捉时时间序列的轨迹数据有缺失,进而导致意图识别不准确,增加了机器人运动的不确定性。因此,提出了一种基于支持向量回归(support vector regression,SVR)和长短期记忆(long short-term memory,LSTM)的人体上肢运动时间序列轨迹缺失补偿方法。采用网格搜索法对SVR模型中的参数进行优化来完善历史样本数据集,结合长短期记忆网络对短、长时间序列轨迹缺失的预测补全更精确的优势,将SVR模型补全的历史样本数据集输入LSTM模型训练,进一步降低补偿误差。实验结果表明,在三维空间350 mm的运动尺度范围内,轨迹缺失程度为10%时,SVR-LSTM模型补偿轨迹的平均误差是0.14 mm;轨迹缺失程度为30%时,SVR-LSTM模型补偿轨迹的平均误差是0.47 mm。

关键词：遮挡轨迹时间序列意图识别轨迹补偿 SVR-LSTM模型

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Commissioning and operation of the cryostat for 3W1 SC wiggler

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Nuclear Science and Techniques 2023年第6期34卷 43-54页

作者： Miao-fu Xu Xiang-Zhen Zhang Rui Ye Jin-Can Wang Xiao-Juan bian Yao Gao Min-Xian Li fu-San Chen Xiao-Chen Yang Rui Ge Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Key Laboratory of Particle Acceleration Physics and Technology Chinese Academy of SciencesBeijing100049China Center for Superconducting RF and Cryogenics Institute of High Energy PhysicsBeijing100049China University of Chinese Academy of Sciences Beijing100049China

A 3W1 superconducting wiggler(SCW)with the pole gap of 68 mm was successfully tested and installed in a BEPC II storage ring in November,*** goal of zero liquid helium consumption was achieved,and the cryogenic system exhibited a 12%residual cooling capacity(approximately 0.69 W@4.2 K).The 3W1-SCW was set to operate at 2.49 T and has been operating for more than seven *** instances of magnet quenching occurred during the normal *** evaporated helium gas can be recycled to the helium gas recycling system when the pressure in the helium tank is higher than the parameter value(the setpoint of the pressure value is 1.2 bara).The cryogenic system can be recovered within 4 h if sufficient liquid helium is available to inject into the cryostat.

关键词： Cryostat Commissioning SC wiggler Synchrotron radiation

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Clinical effects of Xingnao Kaiqiao acupuncture on neurological impairment following cerebral infarction

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Neural Regeneration Research 2008年第3期3卷 272-275页

作者： Jie Xiong Lina ning Jinling bian Jun Li Junfeng Xu Zhilong Zhang Jiakui Guo YadongLi Xuemin Shi Department of Traditional Chinese Medcine Rehabilitation and Physiotherapy the Affiliated Hospital of Medical College of Chinese Armed Police Forces Tianjin 300162 China The Specialty of Acupuncture and Manipulation Tianjin University of Traditional Chinese Medicine Tianjin 300193 China Department of Acupuncture the First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300193 China Department of Acupuncture Tianjin Traditional Chinese Medicine Hospital Tianjin 300140 China Department of Acupuncture the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300150 China

BACKGROUND： Although the curative effects of acupuncture have been confirmed by various treatments of cerebral infarction, few studies have investigated when acupuncture can attain the best clinical effect. OBJECTIVE： Four different time points were selected for acupuncture treatment of cerebral infarction to evaluate the appropriate time course for Xingnao Kaiqiao therapy in terms of improved neurological function. DESIGN： Controlled observation. SETTING： Department of Traditional Chinese Medicine Rehabilitation and Physiotherapy of the Affiliated Hospital of Medical College of Chinese Armed Police Forces. PARTICIPANTS： A total of 120 inpatients with cerebral infarction of different stages, including 75 males and 45 females, aged 41-75 years, were selected from November 2005 to December 2006 at the Department of Traditional Chinese Medicine Rehabilitation and Physiotherapy in Affiliated Hospital of Medical College of Chinese Armed Police Forces. Diagnostic criteria： in accordance with ＂main points of diagnosis on different cerebrovascular disease＂ secondly revised in the Second Cerebrovascular Disease Academic Meeting of Chinese Medicine Association in 1986. All accepted subjects provided confirmed consent, and the experiment received ethical permission from the hospital＇s ethics committee. METHODS： ① Experiment grouping： All inpatients were divided into four groups with non-stochastic concurrent control method according to the disease course： Group Ⅰ （onset within 7 hours）, group Ⅱ （onset from 7 hours to 3 days）, group Ⅲ （onset within 4-7 days）, and group IV （onset within 21-180 days）. On the basis of symptomatic treatment with western medicine, each group received Xingnao Kaiqiao therapy after onset within 7 hours, 7 hours to 3 days, 4 to 7days, and 21 to 180 days. ① The principal acupoints were Neiguan, Renzhong, and Sanyinfiao. ② The auxiliary acupoints were Jiquan, Chize, and Weizhong. ③Acupuncture manipulations： initially, Neiguan （PC6, bilateral） was needled

关键词： cerebral infarction Xingnao Kaiqiao acupuncture acupuncture therapy clinical effects intervention time

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An explicit time domain solution for ground stratum response to harmonic moving load

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Acta Mechanica Sinica 2006年第5期22卷 469-478页

作者： Xuecheng bian Yunmin Chen College of Civil Engineering and Architecture Zhejiang University Hangzhou 310027 China

Based on the thin layer method originally proposed in frequency domain, an explicit time domain semi-analytical solution has been developed for simulating three-dimensional layered ground responses to harmonic moving loads. The Fourier-Laplace transforms were applied to derive the transformed solution that satisfied the boundary conditions of horizontal infinities. The eigenvalue decomposition was performed with respect to Laplace parameter to express the ground motion corresponding to the eigenmodes. The formulation for each eigenmode incorporating the moving load expression was transformed back into time domain analytically, and the global system responses were given by means of the general mode superposition method. The proposed explicit time domain solution is suitable for studying various types of moving load acting on or inside the ground. In this paper a moving harmonic load with rectangular distribution was adopted to demonstrate the ground response simulation. Two illustrative examples for moving load with speeds below or above the ground Rayleigh wave velocity were presented to test the computational accuracy and efficiency of the proposed approach. A parametric study was also performed to investigate the influences of soil properties on the ground responses.

关键词： Moving harmonic load Thin layer method Laplace transform Fourier transform Layered soils

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CO_2 absorption into a phase change absorbent: Water-lean potassium prolinate/ethanol solution

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2318-2326页

作者： Yangyang bian Shufeng Shen School of Chemical and Pharmaceutical Engineering Hebei University of Science and Technology

Phase change solvents are attractive energy-efficient absorbents for carbon dioxide(CO_2) capture due to CO_2-rich phase formation. Potassium prolinate + water + ethanol(ProK/W/Eth) solution has shown good capture characteristics as a promising one in our previous work. In this work, absorption rate of CO_2, solubility of N2 O,and heat of absorption for ProK/W/Eth solution were investigated using a stirred cell reactor and a CPA201 reaction calorimeter and these results were also compared with the aqueous ProK and 30 mass% MEA *** ethanol as a solvent can substantially increase the CO_2 physical solubility and the absorption rate of CO_2 in ProK/W/Eth solutions is far higher than that in aqueous 30 mass% MEA solutions especially at a low CO_2 loading range. Solid precipitation, obtained from the liquid-to-solid phase change absorption, was analyzed by13 C NMR and DSC-TGA. The enthalpy change for ProK/W/Eth solutions at various CO_2 loading was also discussed.

关键词： CO2 absorption Phase change absorbent Potassium prolinate Ethanol Heat of absorption

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Parameter optimization of controllable local degree of freedom for reducing vibration of flexible manipulator

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Chinese Journal of Aeronautics 2013年第2期26卷 487-494页

作者： bian Yushu Gao Zhihui School of Mechanical Engineering and Automation Beihang University State Key Laboratory for Robotics and System (HIT) Harbin Institute of Technology

Parameter optimization of the controllable local degree of freedom is studied for reducing vibration of the flexible manipulator at the lowest possible cost. The controllable local degrees of freedom are suggested and introduced to the topological structure of the flexible manipulator, and used as an effective way to alleviate vibration through dynamic coupling. Parameters introduced by the controllable local degrees of freedom are analyzed and their influences on vibration reduction are investigated. A strategy to optimize these parameters is put forward and the corresponding optimization method is suggested based on Particle Swarm Optimization （PSO）. Simulations are conducted and results of case studies confirm that the proposed optimization method is effective in reducing vibration of the flexible manipulator at the lowest possible cost.

关键词： Degrees of freedom Flexible manipulators Optimization Particle Swarm Optimization Vibration control

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