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A new global land productivity dynamic product based on the consistency of various vegetation biophysical indicators

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Big Earth Data 2022年第1期6卷 36-53页

作者： Yuran Cui xiaosong li Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina

Changes in land productivity have been endorsed by the Inter Agency Expert Group on Sustainable Development Goals(IAEGSDGs)as key indicators for monitoring SDG *** vegeta-tion parameters from optical remote sensing techniques have been widely utilized across different land productivity decline processes and ***,there is no consensus on indicator selection and their effectiveness at representing land productivity declining at different *** study proposes a fusion framework that incorporates the trends and consistencies within the four com-monly used remote sensing-based vegetation *** ana-lyzed the differences among the four vegetation parameters in different land cover and climate zones,finally producing a new global land productivity dynamics(LPD)product with confidence level *** LPD classes indicated by the four vegetation indicators(VIs)showed that all three levels(low,medium,and high confidence)of increasing area account for 23.99%of the global vegetated area and declining area account for 7.00%.The Increase high-confidence(HC)area accounted for 2.77%of the total area,and the Decline-HC accounted for 0.35%of the total *** study demonstrates the accuracy of the high-confidence(HC)area for the evaluation of land productivity decline and ***“forest”landcover type and“humid”climate zone had the largest increasing and declining area but had the lowest high-confidence *** data product provides an important and optional reference for the assessment of SDG 15.3.1 at global and regional scales according to the specific application target.

关键词： Sustainable development goals SDG 15.3.1 vegetation parameters confidence level google Earth engine

Numerical Analysis of Energy Effect in Laser-TIG Hybrid Welding

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Journal of Materials Science & Technology 2003年第z1期19卷 23-26页

作者： Yanbin CHEN liqun li Junfei FANG xiaosong FENG National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna

The hybrid source that combined CO2 laser with TIG arc to proceed welding was analyzed. Based on an energymodel, the temperature field and weld shape were calculated numerically. The heat transfer characteristic of thehybrid heat source to workpiece and its effect to weld shape were also analyzed. Through analyzing the enhancementeffect of the hybrid heat source, the absorption effect and defocusing effect of the hybrid arc to laser were calculated,and the regularity of the energy density to the current was obtained subsequently. At last, the critical energy matchesto induce the enhancement effect of CO2 laser-TIG arc hybrid welding were obtained.

关键词： Laser-TIG hybrid welding, Energy effect, Numerical simulation

Mantis Shrimp-Inspired Underwater Striking Device Generates Cavitation

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Journal of Bionic Engineering 2022年第6期19卷 1758-1770页

作者： Xinxin li xiaosong li Xin Hou Yuanzhe li Yonggang Meng liran Ma Yu Tian State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing100084China

Different from direct impact damage exerted by limbs of most organisms,mantis shrimps’appendages can carry out ultra-fast,powerful underwater strikes with cavitation superimposed damage to harvest hard-shelled *** power amplification systems and cavitation generation of mantis shrimp have attracted vast attention of *** effort has been paid to developing mantis shrimp-inspired striking robots;however,none of them are capable of generating cavitation during impacting hard objects *** this paper,an underwater striking robot named Shrimpbot was developed to reproduce the cavitation phenomenon when striking hard *** incorporates a Latch-Mediated Spring Actuation(LaMSA)to slowly store energy and release it instantaneously.A Diamond-Shaped Four-bar linkage(DSFL)stretches springs to more effectively store elastic energy by reducing the maximum torque requirement of the *** design promised an average power amplification of over 30 times of the *** optimization and hydrophobic coating on the hammerhead and hand of Shrimpbot helped to reduce the water *** accomplished Shrimpbot reached an impact speed of over 12 m/s,at an acceleration of 2×10^(3) m/s^(2),an impact force of more than 1200 N in water,very close to the performance of mantis *** importantly,cavitation bubbles accompanied with the impacts were observed for the first time in mantis shrimp-inspired *** ingeniously employs only one motor to accomplish the striking automatically and repeatedly for practical *** mimics the cavitation generation skills of mantis shrimp,which could facilitate the understanding of its mechanical principles and fluid dynamics of ultra-fast power-amplified systems of mantis shrimp and even those energy storage mechanisms of jumping robots or exoskeleton robots.

关键词： Mantis shrimp Biomechanics Power amplification Cavitation Latch-mediated spring actuation

Research on Weapon Equipment Civil-Military Integration Development Mode Based on Fuzzy Petri Net 36

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Research on Weapon Equipment Civil-Military Integration Deve...

Robust scalable reversible strong adhesion by gecko-inspired composite design

第36届中国控制会议

作者： xiaosong li Bin Lv China Defense Science and Technology Information Center

ISBN: (纸本)9781538629185

Scientific and rational weapon equipment Civil-Military Integration development mode is the basis for the realization of Civil-Military Integration *** paper defined the concept of weapon equipment Civil-Military Integration development mode,introduced the Fuzzy Petri Net,analyzed the influencing factors and types of the development mode,construct the selection model of development mode,and analyzed the *** research conclusion provided reference for our country to design the weapon equipment Civil-Military Integration development mode.

关键词： Fuzzy Petri Net Weapon Equipment Construction Civil-Military Integration Development Mode

来源： cnki会议评论

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Friction 2022年第8期10卷 1192-1207页

作者： xiaosong li Pengpeng BAI Xinxin li Lvzhou li Yuanzhe li Hongyu LU liran MA Yonggang MENG Yu TIAN State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Bio-inspired reversible adhesion has significant potential in many fields requiring flexible grasping and manipulation,such as precision manufacturing,flexible electronics,and intelligent *** extensive efforts for adhesive synthesis with a high adhesion strength at the interface,an effective strategy to actively tune the adhesion capacity between a strong attachment and an easy detachment spanning a wide range of scales has been ***,we report a novel soft-hard-soft sandwiched composite design to achieve a stable,repeatable,and reversible strong adhesion with an easily scalable performance for a large area ranging from~1.5 to 150 cm2 and a high load ranging from~20 to 700 *** studies indicate that this design can enhance the uniform loading for attachment by restraining the lateral shrinkage in the natural state,while facilitate a flexible peeling for detachment by causing stress concentration in the bending state,yielding an adhesion switching ratio of~54 and a switching time of less than~0.2 *** design is further integrated into versatile grippers,climbing robots,and human climbing grippers,demonstrating its robust scalability for a reversible strong *** biomimetic design bridges microscopic interfacial interactions with macroscopic controllable applications,providing a universal and feasible paradigm for adhesion design and control.

关键词： biomimetic design reversible adhesion composite cross-scale robotics

Did Ecological Engineering Projects Have a Significant Effect on Large-scale Vegetation Restoration in Beijing-Tianjin Sand Source Region, China？ A Remote Sensing Approach

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Chinese Geographical Science 2016年第2期26卷 216-228页

作者： li xiaosong WANG Hongyan ZHOU Shufang SUN Bin GAO Zhihai Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing 100094 China Twenty First Century Aerospace Technology Co. Ltd. Beijing 100096 China Institute of Forest Resources Information Technique Chinese Academy of Forestry Beijing 100091 China

Aiming for the restoration of degraded ecosystems, many ecological engineering projects have been implemented around the world. This study investigates the ecological engineering project effectiveness on vegetation restoration in the Beijing-Tianjin Sand Source Region(BTSSR) from 2000 to 2010 based on the rain use efficiency(RUE) trend in relation to the land cover. More than half of the BTSSR experienced a vegetation productivity increase from 2000 to 2010, with the increasing intensity being sensitive to the indicators chosen. A clear tendency towards smaller increasing areas was shown when using the net primary productivity(NPP, 51.30%) instead of the accumulated normalized difference vegetation index(59.30%). The short-term variation in the precipitation and intra-seasonal precipitation distribution had a great impact on the remote sensing-based vegetation productivity. However, the residual trends method(RESTREND) effectively eliminated this correlation, while incorporating the variance and skewness of the precipitation distribution increased the models′ ability to explain the vegetation productivity variation. The RUE combined with land cover dynamics was valid for the effectiveness assessment of the ecological engineering projects on vegetation restoration. Particularly, the result based on growing season accumulated normalized difference vegetation index(ΣNDVI) residuals was the most effective, showing that 47.39% of the BTSSR experienced vegetation restoration from 2000 to 2010. The effectiveness of the ecological engineering projects differed for each subarea and was proportional to the strength of ecological engineering. The water erosion region dominated by woodland showed the best restoration, followed by the wind-water erosion crisscross regions, while the wind erosion regions dominated by grassland showed the worst effect. Seriously degraded regions still cover more area in the BTSSR than restored regions. Therefore, more future effort should be put i

关键词： vegetation restoration ecological engineering rain use efficiency(RUE) residual trends method(RESTREND) Beijing-Tianjin Sand Source Region(BTSSR)

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The investigation of NTO/HMX-based plastic-bonded explosives and its safety performance

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Defence Technology（防务技术） 2022年第1期18卷 72-80页

作者： li-xiaosong Du Shao-hua Jin Qing-hai Shu li-jie li Kun Chen Ming-lei Chen Jun-feng Wang School of Materials Science and Engineering Beijing Institute of Technology Beijing China Garsu Yinguang Chemical Industry Group Coltd Baiyin China State Key Laboratory of Explosion Science and Technobogy Beijing Institute of TechnologyBeijing China

3-nitro-1,2,4-triazol-5-one(NTO)is the main component of insensitive munitions(IM)formulation because of its outstanding insensitive *** this paper,a series of NTO/HMX-based compositeexplosives were prepared and *** study focuses on the effect of NTO on the perfommance of the formulations,especially the safety *** results revealed that the mechanical sensi-tivity of fomulations was associated with NTO content,as well as the thermal conductivity,specific heat capacity and Arrhenius ***,the high amount of NTO using in formulation was proved to be helpful for NTO/HMX-based formulation to exhibit good thermal ***,by accelerating rate calorimeter(ARC)and a modified cook-off equipment,the pressure and pressure rise rate were proved as the important indicator for judging the thermal safety performance in confined ***,the numerical simulation was used as a credible method for predicting the respond temperature of cook-off experiment.

关键词： 3-nitro-1,2,4-triazol-5-one(NTO) Plastic-bonded explosive(PBX) Safety performance Cook-off

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Private hospital expansion in China:a global perspective

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Global Health Journal 2018年第2期2卷 33-46页

作者： Chenhui Deng xiaosong li Jay Pan West China School of Public Health Sichuan UniversityNo.17Section 3Ren Min Nan RoadChengdu 610041China West China Research Center for Rural Health Development Sichuan UniversityNo.17Section 3Ren Min Nan RoadChengdu 610041China

Objective:To assess the private hospital development in China during 2005-2016 from a global ***:We searched the English and Chinese literature in PubMed,CNKI and Google Scholar databases with the keywords including“private hospitals in China”,“hospital ownership”,“public and private hospital”,“private hospital development”.Descriptive statistical analysis was used to assess the trend of the private hospital development in China and *** the change of private hospitals in supply capacity and health care delivery were studied in this *** number of hospitals,number of hospital beds and the average number of hospital beds per hospital were employed to measure the supply *** visit number,inpatients number,and bed occupancy rate(BOR)were used to measure the healthcare *** data was collected from the China Health Statistical Yearbook and the“Organisation for Economic and Co-operation and Development(OECD)Statistics”***:The private sector rapidly expanded in China’s hospital market in recent *** number of private hospitals exceeded the public in *** has also been a signi cant rise for the indicators of both the supply capacity(including number of hospitals,number of hospital beds and the average number of hospital beds per hospital)and the health care delivery(inpatients number and BOR)of the private ***,the growth rates of them were relatively lower than the *** expansion trend of China’s private sector in the hospital market accorded with most the OECD countries around the *** 2016,China was above the medium level of the share of the private hospitals’number with the OECD countries,but below the medium for the supply capacity,in terms of the hospital ***:As a result of the economic growth and supporting policy,the private sector has experienced a vast expansion in China’s hospital market in the past *** rising gap in average size between private and pub

关键词： private hospital publicly owned hospital health reform China

Analysis of diagnosis and treatment of lipoblastomatosis

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Science China(life Sciences) 2017年第7期60卷 778-780页

作者： Zhiqiang Mo Xianghui Xie Huanmin Wang Hong Qin Wei Han xiaosong li Department of Pediatric Surgery Beijing Children's Hospital Capital Medical University National Center for Children's Health Beijing 100045 China

Dear Editor,lipoblastomatosis is a rare benign soft tissue tumor arising from the white fetal-embryonal adipose tissue（Choi et al.,2013）.Since the distinction of lipoblastomatosis from lipoblastma was reported by Ve... 详细信息

关键词：母细胞治疗诊断脂肪

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