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Goaf risk prediction based on IAOA-SVM and numerical simulation:A case study

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Underground Space 2024年第2期15卷 153-175页

作者： Mingliang li Kegang li Yuedong liu Shunchuan Wu qingci qin Rui Yue Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Sino-German Blue Mining and Utilization of Special Underground Space Kunming 650093China Yunnan Diqing Mining Co.Ltd. Shangrila 674400China

In regard to goaf risk prediction,due to the low accuracy and single prediction method,this study proposes a method that combines the improved arithmetic optimization algorithm(IAOA)–support vector machines(SVM)with GoCAD–FLAC^(3D)numerical ***,goaf risk is comprehensively *** the perspectives of geological and engineering conditions,eight factors that affect goaf stability and 176 sets of sample data were *** utilized eight influencing factors such as rock mass structure,geological structure,and goaf burial depth as inputs,and the goaf risk level as the ***,an IAOA–SVM goaf risk prediction model was *** 30 goaf areas of Yangla Copper Mine in Yunnan Province were selected as the research ***,the rationality of mechanical parameter values in the numerical model was verified using the parameter inversion ***,based on the GoCAD–FLAC^(3D)numerical simulation method,the goaf risk analysis in Yangla Copper Mine was ***,using numerical simulation verification,the goaf filling effect was ***,the prediction results of the IAOA–SVM model were compared with that of other intelligent *** results indicate that the numerical simulation results of the GoCAD–FLAC^(3D)model are consistent with those of IAOA–SVM and the actual results,which further verifies the effectiveness and superiority of the IAOA–SVM prediction ***,an innovative approach for goaf risk prediction is developed.

关键词： Rock mechanics Goaf risk prediction IAOA SVM Numerical simulation

Design and calibration of spoke piezoelectric six-dimensional force/torque sensor for space manipulator

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Chinese Journal of Aeronautics 2024年第1期37卷 218-235页

作者： Yingjun li Guicong WANG Shuai ZHANG Yuanqin ZHOU Hongyu li Zhenguang qi School of Mechanical Engineering University of JinanJinan 250022China

The large manipulator outside the space cabin is a multi-degree of freedom actuator for space *** order to realize the automatic control and flexible operation of the space manipulator,a novel spoke structure piezoelectric six-dimensional force/torque sensor with redundancy ability,high stiffness and good decoupling performance is innovatively *** on the deformation coordination relationship,the redundancy measurement mechanism is *** mathematical models of the sensor with and without branch fault are established *** finite element model is established to verify the feasibility of structure and redundancy measuring principle of the *** on the theoretical analysis and simulation analysis,the prototype of the sensor is *** and dynamic calibration experiments are carried *** actual output voltage signal of the six-dimensional force/torque sensor is collected to establish the equation between the standard input applied load and the actual output voltage *** on ant colony optimized BP algorithm,performance indexes of the sensor with and without branch fault are analyzed *** experimental results show that the spoke piezoelectric sixdimensional force/torque sensor with the eight-point support structure has good accuracy and ***,it has strong decoupling characteristic that can effectively shield the coupling between *** nonlinear errors and maximum interference errors of decoupled data with and without branch faults are less than 1% and 2%,*** natural frequency of the sixdimensional force sensor can reach 2856.45 Hz and has good dynamic *** research content lays a theoretical and experimental foundation for the design,development and application of the new six-dimensional force/torque sensors with ***,it will significantly improve the research level in this field,and provide a strong guarantee for the smoot

关键词： Decoupling algorithm Piezoelectric Redundancy Six-dimensional force/torque sensor Space manipulator

Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong Hui li Ya‑qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Deep Video Harmonization by Improving Spatial-temporal Consistency

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Machine Intelligence Research 2024年第1期21卷 46-54页

作者： Xiuwen Chen li Fang Long Ye qin Zhang Key Laboratory of Media Audio and Video Ministry of Education Communication University of ChinaBeijing 100024China

Video harmonization is an important step in video editing to achieve visual consistency by adjusting foreground appear-ances in both spatial and temporal *** methods always only harmonize on a single scale or ignore the inaccuracy of flow estimation,which leads to limited harmonization *** this work,we propose a novel architecture for video harmoniza-tion by making full use of spatiotemporal features and yield temporally consistent harmonized *** introduce multiscale harmon-ization by using nonlocal similarity on each scale to make the foreground more consistent with the *** also propose a fore-ground temporal aggregator to dynamically aggregate neighboring frames at the feature level to alleviate the effect of inaccurate estim-ated flow and ensure temporal *** experimental results demonstrate the superiority of our method over other state-of-the-art methods in both quantitative and visual comparisons.

关键词： Harmonization temporal consistency video editing video composition nonlocal similarity

From VIB‑to VB‑Group Transition Metal Disulfides:Structure Engineering Modulation for Superior Electromagnetic Wave Absorption

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Nano-Micro Letters 2024年第2期16卷 218-257页

作者： Junye Cheng Yongheng Jin Jinghan Zhao qi Jing Bailong Gu Jialiang Wei Shenghui Yi Mingming li Wanli Nie qinghua qin Deqing Zhang Guangping Zheng Renchao Che Department of Materials Science Shenzhen MSU-BIT UniversityShenzhen 517182People’s Republic of China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China

The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,*** recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried ***,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the *** this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are *** compositions,microstructures,electronic properties,and synthesis methods are presented in ***,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption *** as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.

关键词： Transition metal disulfides Electromagnetic wave absorption Impedance matching Structure engineering modulation

The biosynthesis of alarm pheromone in the wheat aphid Rhopalosiphum padi is regulated by hormones via fatty acid metabolism

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Journal of Integrative Agriculture 2024年第7期23卷 2346-2361页

作者： Chengxian Sun Yaoguo qin Julian Chen Zhengxi li Department of Entomology/Ministry of Agriculture Key Laboratory for Monitoring and Environment-friendly Control of Crop Pests College of Plant ProtectionChina Agricultural UniversityBeijing 100193China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China

Aphids are major insect pests in agriculture and forestry *** attacks by natural enemies,many aphids release an alarm pheromone to protect their *** most aphids,the main component of the aphid alarm pheromone(AAP)is the sesquiterpene hydrocarbon(E)-β-farnesene(EβF).However,the mechanisms behind its biosynthesis and regulation remain poorly *** this study,we used the bird cherry–oat aphid Rhopalosiphum padi,which is an important wheat aphid,to investigate the regulatory mechanisms of EβF *** results showed that EβF biosynthesis occurs during the mature embryo period and the molting period of the 1st-and 2nd-instar *** provide the prerequisite material for EβF production and *** on transcriptome sequencing,RNAi analysis,hormone treatments,and quantitative measurements,we found that the biosynthesis of EβF utilizes acetyl coenzyme A produced from fatty acid degradation,which can be suppressed by juvenile hormone but it is promoted by 20-hydroxyecdysone through the modulation of fatty acid *** is the first systemic study on the modulation of EβF production in *** results of our study provide insights into the molecular regulatory mechanisms of AAP biosynthesis,as well as valuable information for designing potential aphid control strategies.

关键词： (E)-β-farnesene critical period for biosynthesis fatty acid metabolism juvenile hormone 20-hydroxyecdysone

Whole-process case management effects on mental state and selfcare ability in patients with liver cancer

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 833-841页

作者： Man-Di Ju qin qin Meng li Department of Internal Medicine of Abdominal Oncology Hubei Cancer HospitalWuhan 430070Hubei ProvinceChina Department of Hepatological Surgery Wuhan No.1 HospitalWuhan 430000Hubei ProvinceChina Department of Nursing General Hospital of the Yangtze River ShippingWuhan 430014Hubei ProvinceChina

BACKGROUND Regarding the incidence of malignant tumors in China,the incidence of liver cancer ranks fourth,second only to lung,gastric,and esophageal *** case fatality rate ranks third after lung and cervical *** a previous study,the whole-process management model was applied to patients with breast cancer,which effectively reduced their negative emotions and improved treatment adherence and nursing *** In this single-center,randomized,controlled study,60 randomly selected patients with liver cancer who had been admitted to our hospital from January 2021 to January 2022 were randomly divided into an observation group(n=30),who received whole-process case management on the basis of routine nursing mea-sures,and a control group(n=30),who were given routine nursing *** compared differences between the two groups in terms of anxiety,depression,the level of hope,self-care ability,symptom distress,sleep quality,and quality of *** Post-intervention,Hamilton anxiety scale,Hamilton depression scale,memory symptom assessment scale,and Pittsburgh sleep quality index scores in both groups were lower than those pre-intervention,and the observation group had lower scores than the control group(Plity assessment scale-revision in Chinese,and quality of life measurement scale for patients with liver cancer scores in both groups were higher than those pre-intervention,with higher scores in the observation group compared with the control group(Pliver cancer,alleviate symptoms and problems,and improve the level of hope,self-care ability,sleep quality,and quality of life,as well as provide feasible nursing alternatives for patients with liver cancer.

关键词： liver cancer Mental state Self-care ability Whole-process case management life quality Nursing

A nonlinear wake model of a wind turbine considering the yaw wake steering

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Journal of Oceanology and limnology 2024年第3期42卷 715-727页

作者： Yunzhou li Zhiteng GAO Shoutu li Suiping qi Xiaoyu TANG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Multi-function Towing Tank School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Laoshan Laboratory Qingdao 266237China

Duo to fluctuations in atmospheric turbulence and yaw control strategies,wind turbines are often in a yaw *** predict the far wake velocity field of wind turbines quickly and accurately,a wake velocity model was derived based on the method of momentum conservation considering the wake steering of the wind turbine under yaw *** consider the shear effect of the vertical incoming wind direction,a two-dimensional Gaussian distribution function was introduced to model the velocity loss at different axial positions in the far wake region based on the assumption of nonlinear wake *** work also developed a“prediction-correction”method to solve the wake velocity field,and the accuracy of the model results was verified in wake experiments on the Garrad Hassan wind ***,a 33-kW two-blade horizontal axis wind turbine was simulated using this method,and the results were compared with the classical wake model under the same parameters and the computational fluid dynamics(CFD)simulation *** results show that the nonlinear wake model well reflected the influence of incoming flow shear and yaw wake steering in the wake velocity ***,computation of the wake flow for the Horns Rev offshore wind farm with 80 wind turbines showed an error within 8%compared to the experimental *** established wake model is less computationally intensive than other methods,has a faster calculation speed,and can be used for engineering calculations of the wake velocity in the far wakefield of wind turbines.

关键词： far wake wake model wake steering wind shear wind farm

Added Benefit of the Early-Morning-Orbit Satellite Fengyun-3E on the Global Microwave Sounding of the Three-Orbit Constellation

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Advances in Atmospheric Sciences 2024年第1期41卷 39-52页

作者： Juan li Zhengkun qin Guiqing liU Jing HUANG CMA Earth System Modeling and Prediction Centre Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Joint Center for Data Assimilation Research and Applications School of Atmospheric SciencesNanjing University of Information Science&TechnologyNanjing 210044China

The three-orbit constellation can comprehensively increase the spatial coverage of polar-orbiting satellites,but the polar-orbiting satellites currently in operation are only mid-morning-orbit and afternoon-orbit ***-3E(FY-3E)was launched successfully on 5 July 2021 in *** an early-morning-orbit satellite,FY-3E can help form a complete three-orbit observation system together with the mid-morning and afternoon satellites in the current mainstream operational *** this study,we investigate the added benefit of FY-3E microwave sounding observations to the midmorning-orbit Meteorological Operational satellite-B(Met Op-B)and afternoon-orbit Fengyun-3D(FY-3D)microwave observations in the Chinese Meteorological Administration global forecast system(CMA-GFS).The results show that the additional FY-3E microwave temperature sounder-3(MWTS-3)and microwave humidity sounder-2(MWHS-2)data can increase the global coverage of microwave temperature and humidity sounding data by 14.8% and 10.6%,*** enables the CMA-GFS to achieve nearly 100% global coverage of microwave-sounding observations at each analysis ***,after effective quality control and bias correction,the global biases and standard deviations of the differences between observations and model simulations are also *** on the Advanced Microwave Sounding Unit A and the Microwave Humidity Sounder onboard Met Op-B,and the MWTS-2 and MWHS-2 onboard FY-3D,adding the microwave sounding data of FY-3E can further reduce the errors of analysis results and improve the global prediction skills of CMA-GFS,especially for the southern-hemisphere forecasts within 96 hours,all of which are significant at the 95% confidence level.

关键词： data assimilation microwave temperature sounder MWTS-3