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Density-based ship detection in SAR images:Extension to a self-similarity perspective

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Chinese Journal of Aeronautics 2024年第3期37卷 168-180页

作者： Xueqian WANG gang LI Zhizhuo JIANG yu LIU You HE Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China

Nonlocal self-similarity is an important property of Synthetic Aperture Radar(SAR)images to characterize the repetitiveness of features embodied by SAR images within nonlocal areas and has been used for enhancement of SAR *** SAR ship detectors often independently handle small sub-images cropped from a large marine SAR image and do not exploit the nonlocal self-similarity *** this paper,we propose a new ship detector from the perspective of nonlocal self-similarity in SAR images to improve the ship detection performance,basically including three stages:prescreening,intra-cue calculation,and inter-cue *** the prescreening stage,we design a new Histogram-based Density(HD)feature to rapidly select candidate sub-images potentially containing ship targets from a large SAR *** the intra-cue calculation stage,target cues within a single candidate sub-image are *** the inter-cue calculation stage,thanks to the nonlocal self-similarity among different candidate sub-images in terms of density features,we innovatively extract a weighted superpixel-HD map to obtain accumulated intracues across all the candidate ***,for each candidate sub-image,we fuse its inter-cue and intra-cue to obtain final detection *** results based on real SAR images show that our newly proposed method provides a better target-to-clutter contrast and ship detection performance than those of other state-of-the-art detection approaches.

关键词： Ship detection Synthetic aperture radar(SAR) Density Self-similarity Histogram

Emerging Organic Contaminants in Chinese Surface Water:Identification of Priority Pollutants

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Engineering 2022年第4期8卷 111-125页

作者： Mengmeng Zhong Tielong Wang Wenxing Zhao Jun Huang Bin Wang Lee Blaney Qingwei Bu gang yu Beijing Key Laboratory for Emerging Organic Contaminants Control State Key Joint Laboratory of Environment Simulation and Pollution Control(SKLESPC)School of EnvironmentTsinghua UniversityBeijing 100084China Department of Chemical Biochemicaland Environmental EngineeringUniversity of Maryland Baltimore CountyBaltimoreMD 21250USA School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

The occurrence and impacts of emerging organic contaminants(EOCs)in the aquatic environment have gained widespread attention over the past two *** to large number of potential contaminants,monitoring campaigns,treatment plants,and proposed regulations should preferentially focus on specific pollutants with the highest potential for ecological and human health *** the present study,a multi-criteria screening approach based on hazard and exposure potentials was developed for prioritization of 405 unregulated EOCs already present in Chinese surface *** potential,exposure potential,and risk quotients for ecological and human health effects were quantitatively analyzed and used to screen *** hazard potential was defined by contaminant persistence,bioaccumulation,ecotoxicity,and human health effects;similarly,the exposure potential was a function of contaminant concentration and detection *** total,123 compounds passed the preselection process,which involved a priority index equal to the normalized hazard potential multiplied by the normalized exposure *** on the prioritization scheme,11 compounds were identified as top-priority,and 37 chemicals were defined as *** results obtained by the priority index were compared with four other prioritization schemes based on exposure potential,hazard potential,or risk quotients for ecological effects or human *** priority index effectively captured and integrated the results from the more simplistic prioritization *** on identified data gaps,four uncertainty categories were classified to recommend:①regular monitoring,derivation of environmental quality standards,and development of control strategies;②increased monitoring;③fortified hazard assessment;and④increased efforts to collect occurrence and toxicity ***,20 pollutants were recommended as priority *** prioritized list of contaminants provides the necessary information for autho

关键词： Prioritization Emerging organic contaminants Hazard potential Ecotoxicity Risk assessment

单孔与多孔腹腔镜子宫肌瘤剥除术临床应用比较

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中国医疗器械信息 2024年第14期30卷 29-31页

作者：胡昕余钢罗文群罗姚金平亮江西省人民医院(南昌医学院第一附属医院)妇科江西南昌330006

目的:探讨单孔腹腔镜子宫肌瘤剥除术的可行性及效果。方法:选取2020年7月~2022年7月本院的80例需要行子宫肌瘤剥除术的患者,随机分为单孔和多孔腹腔镜组,各40例。比较两组手术时间、术中出血量、术后疼痛评分(VAS评分)、术后住院时间及... 详细信息

目的:探讨单孔腹腔镜子宫肌瘤剥除术的可行性及效果。方法:选取2020年7月~2022年7月本院的80例需要行子宫肌瘤剥除术的患者,随机分为单孔和多孔腹腔镜组,各40例。比较两组手术时间、术中出血量、术后疼痛评分(VAS评分)、术后住院时间及患者满意情况。结果:80台手术均顺利完成,单孔腹腔镜组患者手术时间、术中出血量与多孔腹腔镜组相比差异无统计学意义(P>0.05),但单孔腹腔镜组术后患者疼痛评分低、住院时间短、满意度增加,差异有统计学意义(P<0.05)。两组手术患者均无并发症。结论:单孔腹腔镜术不仅具有减轻术后疼痛,促进术后快速康复,而且切口美观隐匿,患者治疗满意。

关键词：单孔腹腔镜多孔腹腔镜子宫肌瘤剥除术

Exit morphology and mechanical property of FDM printed PLA: influence of hot melt extrusion process

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Advances in Manufacturing 2023年第1期11卷 56-74页

作者： Yan-Hua Bian gang yu Xin Zhao Shao-Xia Li Xiu-Li He Chong-Xin Tian Zhi-Yong Li Institute of Mechanics Chinese Academy of SciencesBeijing100190People’s Republic of China School of Engineering Science University of Chinese Academy of SciencesBeijing100049People’s Republic of China Research Institute of 3D Printing Beijing City UniversityBeijing100083People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049People’s Republic of China

In order to study the hot melt extrusion process in fused deposition modeling(FDM),this study mainly explores the effects of printing temperature,heated block length,feeding speed on the exit morphology and mechanical properties of FDM printed Polylactic acid(PLA)***-speed camera is used to capture the exit morphology of molten PLA just extruded to the *** to exit morphology,the outlet states of extruded molten material can be divided into four categories,namely,bubbled state,coherent state,expanding state,and unstable *** test results show that printing temperature,heated block length and printing speed have significant influence on tensile properties and fracture mode of FDM printed *** the heated block length is 15 mm and 30 mm,there is a ductile-brittle transition in fracture mode with the increase of printing *** printing process window under different heated block lengths and printing temperatures has been figured out and the distribution of printing process window under different printing speeds has been *** is a maximum printing process window under the heated block length of 30 *** finding provides a frame work for performance prediction of FDM printed parts and theoretical guidance for expanding the scope of printing process window.

关键词： Fused deposition modeling(FDM) Polylactic acid(PLA) Exit morphology Tensile property Printing process window

血清ANGPTL4、cTnI及mACEF评分与冠心病患者PCI术风险及术后临床结局的关系探究

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现代生物医学进展 2024年第15期24卷 2915-2919页

作者：马前锋张涛薛玉刚刘蕾王磊西安交通大学附属西安市中心医院心内科陕西西安710003 空军军医大学第二附属医院心内科陕西西安710038 西安交通大学第一附属医院心内科陕西西安710061

目的:探究血清血管生成素样蛋白4(ANGPTL4)、心肌肌钙蛋白I(cTnI)及年龄、肌酐清除率、射血分数(mACEF)评分与冠心病患者经皮冠状动脉介入(PCI)术风险及术后临床结局的关系。方法:将自2020年1月至2022年10月在我院行行PCI术的108例冠心... 详细信息

目的:探究血清血管生成素样蛋白4(ANGPTL4)、心肌肌钙蛋白I(cTnI)及年龄、肌酐清除率、射血分数(mACEF)评分与冠心病患者经皮冠状动脉介入(PCI)术风险及术后临床结局的关系。方法:将自2020年1月至2022年10月在我院行行PCI术的108例冠心病患者纳入研究,根据欧洲心脏手术风险评估系统(EuroSCORE)Ⅱ评分评估PCI术风险,分为高危组和非高危组。所有患者术前均进行mACEF评分和EuroSCOREⅡ评分,检测血清ANGPTL4、cTnI表达水平;随访12个月,记录心血管不良事件发生情况;比较高危组与非高危组血清ANGPTL4、cTnI及mACEF评分,分析血清ANGPTL4、cTnI及mACEF评分与Euro SCOREⅡ评分的关系及对心血管不良事件的预测效能。结果:高危组血清ANGPTL4、cTnI水平及mACEF评分均高于非高危组(P<0.05);经Pearson相关性分析,冠心病患者血清ANGPTL4、cTnI水平及mACEF评分均与EuroSCOREⅡ评分呈正相关(P<0.05);在108例行PCI术的冠心病患者中,随访12个月期间,发生心血管不良事件20例,占18.52%;心血管不良事件组血清ANGPTL4、cTnI水平及mACEF评分均高于非心血管不良事件组(P<0.05);经多因素Logistic回归分析,血清ANGPTL4、cTnI水平及mACEF评分均是冠心病患者PCI术后心血管不良事件的独立影响因素(P<0.05);经ROC曲线分析,血清ANGPTL4、cTnI水平联合mACEF评分预测冠心病患者PCI术后心血管不良事件的敏感度为90.32%、特异度为52.37%、AUC为0.901。结论:血清ANGPTL4、cTnI及mACEF评分与冠心病患者PCI术风险密切相关,联合预测术后临床结局的效能较好。

关键词：冠心病经皮冠状动脉介入术血管生成素样蛋白4 心肌肌钙蛋白I mACEF评分临床结局

Infrared Photodetectors and Image Arrays Made with Organic Semiconductors

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高分子科学:英文版 2023年第10期41卷 1629-1637页

作者： Zhi-Ming Zhong Feng Peng Lei Ying Zhen-Qiang Huang Wen-Kai Zhong gang yu Yong Cao Fei Huang Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640China

Combining the strategies of introducing larger heteroatom,regio-regular backbone and extended branching position of side-chain,we developed polymer semiconductors(PPCPD)with narrow band-gap to construct the photosensing layer of thin-film photodiodes and image *** spectral response of the resulting organic photodiodes spans from the near ultra-violet to short-wavelength infrared *** performance of these short-wavelength infrared photodiodes in 900–1200 nm range achieved a level competitive with that of indium gallium arsenide-based inorganic crystalline detectors,exhibiting a specific detectivity of 5.55×1012 Jones at 1.15µ*** photodetectivity and quantum efficiency in photodiode with amorphous/nanocrystalline thin-films of 100–200 nm thickness enabled high pixel-density image arrays without pixel-level-patterning in the sensing layer.1×256 linear diode arrays with 25µm×25µm pixel pitch were achieved,enabling high pixel-density short-wavelength infrared imaging at room temperature.

关键词： Conjugated polymer Organic semiconductor Infrared Photodetector Image array

Effect of iron ion configurations on Ni^(2+) removal in electrocoagulation

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Journal of Environmental Sciences 2023年第2期124卷 823-834页

作者： Xiaoliu Lü Tao Xu Yihui Zhou Qingjuan Peng Jinhua Ou Bonian Hu Zhihui Xie Xiping Lei gang yu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China Research Institute of New Building Materials Hunan Institute of TechnologyHengyang 421008China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province College of Chemistry and Chemical EngineeringChina West Normal UniversityNanchong 637002China Hunan Zihong Ecology Technology Co. Ltd.Changsha 410000China

Electrocoagulation(EC)has been widely used to treat the heavymetal wastewater in industry.A novel process of sinusoidal alternating current electrocoagulation(SACC)is adopted to remove Ni2+in wastewater in this *** morphology of precipitates and the distribution of the main functional iron configurations were *** timed complex spectroscopy can identify the monomeric iron configurations[Fe(a)],oligomeric iron configurations[Fe(b)]and polymeric iron configurations[Fe(c)].The optimal operating conditions of SACC process were determined through single-factor *** maximum Ni2+removal efficiency[Re(Ni^(2+))]was achieved under the conditions of pH0=7,current density(j)=7 A/m^(2),electrolysis time(t)=25 min,c0(Ni^(2+))=100 mg/*** pH=7,the proportion of Fe(b)and Fe(c)in the system was 50.4 at.% and 23.1 at.%,*** the SACC process,Fe(b)and Fe(c)are themain iron configurations in solution,while Fe(c)are the vastmajority of the iron configurations in the direct current electrocoagulation(DCC)***(Ni2+)is 99.56% for SACC and 98.75% for DCC under the same optimum conditions,*** precipitates produced by SACC have a high proportion of Fe(b)configurations with sphericalα-FeOOH andγ-FeOOH structures which contain abundant hydroxyl ***,it is demonstrated that Fe(b)has better adsorption capacity than Fe(c)through adsorption experiments of methyl orange(MO)***(a)configurations in the homogeneous solution had no effect on the removal of nickel.

关键词： Electrocoagulation Nickel wastewater Iron configurations Alternating current Polynuclear iron-hydroxyl complex

Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China

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Engineering 2024年第6期37卷 69-77页

作者： Hongwei yu Junrong Shao Huawei Jia Diga gang Baiwen Ma Chengzhi Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Changjiang Survey PlanningDesign and Research Co.Ltd.Wuhan 430010China

Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution *** can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially threatening the structure and function of natural *** in terrestrial and aquatic ecosystems alter the growth and functional characteristics of ***,little attention has been given to the possible harm associated with MPs deposited in snow,particularly in the context of global climate *** collected from surface snow in the Inner Mongolia Plateau,China,were used for quantitative analysis and *** results showed that MPs were easily detected,and the related concentration was approximately(68±10)–(199±22)MPsL1 in snow *** were the most common morphology,the polymer composition was largely varied,and the abundance and composition of MPs were linked to human activity to a great ***-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics,indicating a considerable difference in microbial functional *** may have an interference effect on the individual growth and functional expression of microorganisms in *** addition,the results showed that functional living areas(e.g.,landfills and suburban areas)in cities play an important role in the properties of *** instance,the highest abundance of MPs was found in thermal power plants,whereas the abundance of polymers per sample was significantly lower in the suburban *** MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health.

关键词： Human activities Snow Microplastics Microbial community Urban function Environmental effect

Revealing Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles in oxygen/fluorine containing environments:A reactive molecular dynamics study meshing together experimental validation

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Defence Technology（防务技术） 2024年第4期34卷 313-327页

作者： gang Li Chuande Zhao Qian yu Fang Yang Jie Chen Institute of Chemical Materials China Academy of Engineering Physics(CAEP)P.O.Box 919-311Mianyang 621900SichuanChina

Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing *** instance,Al-O reaction is the most common pathway to release limited energy while Al-F reaction has received much attentions to enhance Al combustion ***,microscopic understanding of the Al-O/Al-F reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion *** this work,for the first time,Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion *** RMD simulation systems of Al core/O_(2)/HF,n-Al/O_(2)/HF,and n-Al/O_(2)/CF4 with oxygen percentage ranging from 0%to 100%have been *** n-Al combustion in mixed O_(2)/CF_4 environments have been conducted by constant volume combustion *** results show that Al-O reaction exhibits kinetic benefits while Al-F reaction owns thermodynamic benefits for n-Al *** n-Al/O_(2)/HF,Al-O reaction gives faster energy release rate than Al-F reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/HF and n-Al/O_(2)/CF_4,*** combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion ***,Al-O reaction prefers to occur on the surface regions while Al-F reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-F *** synergistic effect of Al-O/Al-F reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.

关键词： Al-O/Al—F reaction Kinetic benefits Thermodynamic benefits Molecular dynamics Combustion