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Research on intelligent search-and-secure technology in accelerator hazardous areas based on machine vision

Nuclear Science and Techniques 2024年第4期35卷 96-107页

作者： Ying-Lin Ma Yao Wang Hong-Mei shi Hui-jie zhang School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Prompt radiation emitted during accelerator operation poses a significant health risk,necessitating a thorough search and securing of hazardous areas prior to initiation.Currently,manual sweep methods are employed.However,the limitations of manual sweeps have become increasingly evident with the implementation of large-scale accelerators.By leveraging advancements in machine vision technology,the automatic identification of stranded personnel in controlled areas through camera imagery presents a viable solution for efficient search and security.Given the criticality of personal safety for stranded individuals,search and security processes must be sufficiently reliable.To ensure comprehensive coverage,180°camera groups were strategically positioned on both sides of the accelerator tunnel to eliminate blind spots within the monitoring range.The YOLOV8 network model was modified to enable the detection of small targets,such as hands and feet,as well as larger targets formed by individuals near the cameras.Furthermore,the system incorporates a pedestrian recognition model that detects human body parts,and an information fusion strategy is used to integrate the detected head,hands,and feet with the identified pedestrians as a cohesive unit.This strategy enhanced the capability of the model to identify pedestrians obstructed by equipment,resulting in a notable improvement in the recall rate.Specifically,recall rates of 0.915 and 0.82were obtained for Datasets 1 and 2,respectively.Although there was a slight decrease in accuracy,it aligned with the intended purpose of the search-and-secure software design.Experimental tests conducted within an accelerator tunnel demonstrated the effectiveness of this approach in achieving reliable recognition outcomes.

关键词： Search and secure Machine vision Camera Human body parts recognition Particle accelerator Hazardous area

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Quantifying the agreement and accuracy characteristics of four satellite-based LULC products for cropland classification in China

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Journal of Integrative Agriculture 2024年第1期23卷 283-297页

作者： jie Xue Xianglin zhang Songchao Chen Bifeng Hu Nan Wang Zhou shi Department of Land Management Zhejiang UniversityHangzhou 310058China Institute of Applied Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Department of Land Resource Management School of Public Finance and Public AdministrationJiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China

Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of research on assessing the accuracy of their application to croplands in a unified framework.Thus,this study evaluated the spatial and area accuracies of cropland classification for four commonly used global LULC products(i.e.,MCD12Q1V6,GlobCover2009,FROM-GLC and GlobeLand30)based on the harmonised FAO criterion,and quantified the relationships between four factors(i.e.,slope,elevation,field size and crop system)and cropland classification agreement.The validation results indicated that MCD12Q1 and GlobeLand30 performed well in cropland classification regarding spatial consistency,with overall accuracies of 94.90 and 93.52%,respectively.The FROMGLC showed the worst performance,with an overall accuracy of 83.17%.Overlaying the cropland generated by the four global LULC products,we found the proportions of complete agreement and disagreement were 15.51 and 44.72% for the cropland classification,respectively.High consistency was mainly observed in the Northeast China Plain,the Huang-Huai-Hai Plain and the northern part of the Middle-lower Yangtze Plain,China.In contrast,low consistency was detected primarily on the eastern edge of the northern and semiarid region,the Yunnan-Guizhou Plateau and southern China.Field size was the most important factor for mapping cropland.For area accuracy,compared with China Statistical Yearbook data at the provincial scale,the accuracies of different products in descending order were:GlobeLand30,FROM-GLC,MCD12Q1,and GlobCover2009.The cropland classification schemes mainly caused large area deviations among the four products,and they also resulted in the different ranks of spatial accuracy and area accuracy among the four products.Our results can provide valuable suggestions for selecting cropland products at the national or provincial scale and help cropland mapping and reconstr

关键词： global LULC products cropland mapping accuracy evaluation food security China

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Experimental and simulation research on hollow AZ31 magnesium alloy three-channel joint by hot extrusion forming with sand mandrel

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Journal of Magnesium and Alloys 2024年第1期12卷 98-109页

作者： shi Shengnan Wang Hongyu Teng Fei Jiang Lei Sun Juncai Sun jie zhang Shunhu Transportation Engineering College Dalian Maritime UniversityDalianLiaoning 106026China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyangLiaoning 110819China Shagang School of Iron and Steel Soochow UniversitySuzhouJiangsu 215021China

Magnesium alloy is one of the lightest metal structural materials.The weight is further reduced through the hollow structure.However,the hollow structure is easily damaged during processing.In order to maintain the hollow structure and to transfer the stresses during the high temperature deformation,the sand mandrel is proposed.In this paper,the hollow AZ31 magnesium alloy three-channel joint is studied by hot extrusion forming.Sand as one of solid granule medium is used to fill the hollow magnesium alloy.The extrusion temperatures are 230℃ and 300℃,respectively.The process parameters(die angle,temperature,bottom thickness,sidewall thickness,edge-to-middle ratio in bottom,bottom shape)of the hollow magnesium alloy are analyzed based on the results of experiments and the finite element method.The results are shown that the formability of the hollow magnesium alloy will be much better when the ratio of sidewall thickness to the bottom thickness is 1:1.5.Also when edge-to-middle ratio in bottom is about 1:1.5,a better forming product can be received.The best bottom shape in these experiments will be convex based on the forming results.The grain will be refined obviously after the extrusion.Also the microstructures will be shown as streamlines.And these lines will be well agreement with the mold in the corner.

关键词： AZ31 magnesium alloy Three-channel joint Sand Experiments and the finite element Die angle

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Third-Trimester Spontaneous Uterine Rupture After Ultrasound-Guided High-Intensity Focused Ultrasound Therapy

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Maternal-Fetal Medicine 2024年第1期6卷 57-59页

作者： Juanjuan Yang Jiayi zhang Yun shi jie Shui Hongying Qian Department of Obstetrics Suzhou Ninth People's HospitalSuzhou 215000China

To editor:Uterine rupture,despite its low incidence,is a severe obstetric complication that is associated with adverse maternal and neonatal outcomes.Previous uterine scarring is a known risk factor for uterine rupture.Uterine scars can form from hysterotomy after abdominal/hysteroscopic myomectomy,cesarean delivery,or hysteroscopic surgery.Over the past few decades,ultrasound-guided high-intensity focused ultrasound(USgHIFU)has emerged as a non-invasive therapeutic tool and has found wide application for the safe and effective management strategy of uterine fibroids and adenomyosis.

关键词： Uterine rupture Pregnancy Cesarean delivery Ultrasound-guided high-intensify focused ultrasound(USgHIFU)

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Fate of organophosphate esters from the Northwestern Pacific to the Southern Ocean:Occurrence,distribution,and fugacity model simulation

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Journal of Environmental Sciences 2024年第3期137卷 347-357页

作者： Tengda shi Ruijing Li jie Fu Chao Hou Hui Gao Guanjie Cheng Haibo zhang Shuaichen Jin Liang Kong Guangshui Na College of Marine Technology and Environment Dalian Ocean UniversityDalian 116023China Laboratory for coastal marine eco-environment process and carbon sink of Hainan province/Yazhou Bay Innovation Institute Hainan Tropical Ocean UniversitySanya 572022China National Marine Environmental Monitoring Center Dalian 116023China College of Marine Ecology and Environment Shanghai Ocean UniversityShanghai 201306China NCS Testing Technology Co. Ltd.Beijing 10081China

Eleven organophosphate esters(OPEs)in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific Expedition.The concentration of total OPEs ranged from 164.82 to 3501.79 pg/m~3in air and from 4.54 to 70.09 ng/L in seawater.Two halogenated OPEs,tri(chloropropyl)phosphate(TCPP)and tri(2-chloroethyl)phosphate(TCEP),were generally more abundant than the non-halogenated OPEs.A levelⅢfugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross Sea.The model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer,during which the Ross Sea acts as a final OPE sink.Dry and wet deposition dominated the processes involving OPE transfer to seawater.The OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater region.These findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic.

关键词： Organophosphate esters(OPEs) Long-range transport Fugacity model Antarctic Fate

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New indices to balanceα-diversity against tree size inequality

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Journal of Forestry Research 2024年第1期35卷 229-237页

作者： Li zhang Brady K.Quinn Cang Hui Meng Lian Johan Gielis jie Gao Peijian shi College of Ecology and Environment Bamboo Research InstituteNanjing Forestry University159 Longpan RoadNanjing 210037People’s Republic of China Fisheries and Oceans Canada Andrews Biological Station125 Marine Science DriveSt.AndrewsNB E5B 0E4Canada Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesCape Town 7945South Africa Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium College of Life Science Xinjiang Normal University102 Xinyi RoadUrumqi 830054People’s Republic of China

The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(H΄).In forest communities,there are large variations in tree size among species and individu-als of the same species,which result in differences in eco-logical processes and ecosystem functions.However,tree size inequality(TSI)has been largely neglected in studies using the available diversity indices.The TSI in the diameter at breast height(DBH)data for each of 99920 m×20 m forest census quadrats was quantified using the Gini index(GI),a measure of the inequality of size distribution.The generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per quadrat.We also examined the relationships ofα-diversity indices with the GI using correlation tests.The generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions,with most root-mean-square errors(990 out of 999 quadrats)being<0.0030.There were significant positive correlations between each of threeα-diversity indices(i.e.,R,D,and H’)and the GI.Nevertheless,the total abundance of trees in each quadrat did not significantly influence the GI.This means that the TSI increased with increasing spe-cies diversity.Thus,two new indices are proposed that can balanceα-diversity against the extent of TSI in the com-munity:(1−GI)×D,and(1−GI)×H’.These new indices were significantly correlated with the original D and H΄,and did not increase the extent of variation within each group of indices.This study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities,especially in the face of cumulative species loss under global climate change.

关键词： Diameter at breast height(DBH) Gini index Shannon-Wiener index Simpson’s index Quadrat Tree size

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Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids

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Petroleum Science 2024年第1期21卷 551-566页

作者： Li-Li Yang Ze-Yu Liu shi-bo Wang Xian-Bo He Guan-Cheng Jiang jie zhang MOE Key Laboratory of Petroleum Engineering State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Changping DistrictBeijing102249China MOE Key CNPC Drilling Research Institute Changping DistrictBeijing102206China

With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore instability.In this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite partly.The suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of 2.The viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same density.Through multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of WBDFs.The sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was 0.2603.Therefore,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection capacity.This work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs.

关键词： Drilling fluids Weighting materials Filtration control Reservoir protection Stability property

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Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification

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Defence Technology（防务技术） 2024年第1期31卷 375-386页

作者： jie Zhao Zhongjiao shi Yuchen Wang Wei Wang Beijing Institute of Technology Beijing 100081China

This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system uncertainties.First,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference frames.Next,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F dynamics.Then,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression matrix.As long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be achieved.Finally,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations.

关键词： Rotor-missile Adaptive control Parameter identification Quaternion control

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Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue zhang Zhi-jie Hu Qi Zhao Huan-Yu zhang Kuo-Zhi Xu shi-Yu zhang Xin-Yi Pan Chang-Lin Lan jie Ren Xi-Chao Ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight method.The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 cm.The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and JEFF-3.3.Based on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were analyzed.The results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data

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Ethanol extract of Cyathulae Radix inhibits osteoclast differentiation and bone loss

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Chinese Journal of Natural Medicines 2024年第3期22卷 212-223页

作者： shi Liying REN Liuyi LI Jinping LIU Xin LU Jingjing JIA Lujuan XIE Baoping TANG Siyuan LIU Wei zhang jie Department of Pharmachemistry Xiangya School of Pharmaceutical SciencesCentral South UniversityChangsha 410013China Hunan Key laboratory of Diagnostic and Therapeutic Drug Research for Chronic Diseases Central South UniversityChangsha 410013China Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases Ministry of EducationGannan Medical UniversityGanzhou 341000China Xiangya Nursing School Central South UniversityChangsha 410013China The Third Xiangya Hospital Central South UniversityChangsha 410013China

Cyathulae Radix,a traditional Chinese medicine and a common vegetable,boasts a history spanning millennia.It enhances bone density,boosts metabolism,and effectively alleviates osteoporosis-induced pain.Despite its historical use,the molecular mechanisms behind Cyathulae Radix’s impact on osteoporosis remain unexplored.In this study,we investigated the effects and mechanisms of Cyathulae Radix ethanol extract(CEE)in inhibiting osteoporosis and osteoclastogenesis.Eight-week-old female mice underwent ovariectomy and were treated with CEE for eight weeks.Micro-computed tomography(micro-CT)assessed histomorphometric parameters,bone tissue staining observed distal femur histomorphology,and three-point bending tests evaluated tibia mechanical properties.Enzyme-linked immunosorbent assay(ELISA)measured serum estradiol(E2),receptor activator for nuclear factor B ligand(RANKL),and osteoprotegerin(OPG)levels.Osteoclastogenesis-related markers were analyzed via Western blotting(WB)and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,CEE effects on RANKL-induced osteoclast formation and bone resorption were investigated in vitro using tartrate-resistant acid phosphatase(TRAP)staining,qRT-PCR,and WB assay.Compared with the ovariectomy(OVX)group,CEE treatment enhanced trabecular bone density,maximal load-bearing capacity,and various histomorphometric parameters.Serum E2 and OPG levels significantly increased,while Receptor activator of nuclear factor-κB(RANK)decreased in the CEE group.CEE downregulated matrix metallopeptidase 9(MMP-9),Cathepsin K(CTSK),and TRAP gene and protein expression.In bone marrow macrophages(BMMs),CEE reduced mature osteoclasts,bone resorption pit areas,and MMP-9,CTSK,and TRAP expression during osteoclast differentiation.Compared with DMSO treatment,CEE markedly inhibited RANK,TNF receptor associated factor 6(TRAF6),Proto-oncogene c-Fos(c-Fos),Nuclear factor of activated T-cells cytoplasmic 1(NFATc1)expressions,and Extracellular regulated protein kinases(ERK),c-Jun N-terminal kinase

关键词： Osteoporosis Osteoclast BMMs Cyathulae Radix RANKL ER/RANK/NFATc1 signaling pathway

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