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矮行星Haumea系统定心算法的探究

天文学报 2024年第3期65卷 132-140页

作者：郝佳男彭青玉郭碧峰曹江龙洪瑶瑶暨南大学计算机科学系广州510632 暨南大学中法天体测量、动力学与空间科学联合研究实验室广州510632

受地球大气影响,使用地基光学望远镜观测角距离较小的双星系统或主卫星系统时往往会出现星象不可分辨的情况.因此,系统光心位置与系统质心位置可能存在一定的偏差.准确地测量太阳系天体系统质心位置可以改进其轨道参数,有助于揭示太阳... 详细信息

受地球大气影响,使用地基光学望远镜观测角距离较小的双星系统或主卫星系统时往往会出现星象不可分辨的情况.因此,系统光心位置与系统质心位置可能存在一定的偏差.准确地测量太阳系天体系统质心位置可以改进其轨道参数,有助于揭示太阳系的形成与演化.以矮行星Haumea及其亮卫星Hi’iaka的运动为例,仿真系统光心围绕质心扰动的过程,探究视宁度(用星象的半高全宽表示)变化对准确测量光心位置的影响.仿真结果表明,使用二维高斯定心算法测定的系统光心位置随视宁度变化,而修正矩定心算法的定心结果不受视宁度的影响.根据仿真结果,研究能够有效减少视宁度变化对光心位置准确测量影响的定心算法十分必要;同时,新的定心算法还需考虑主星光度变化的影响.使用云南天文台2.4 m望远镜, 1 m望远镜以及紫金山天文台姚安观测站0.8 m望远镜从2022年2月7日至2022年5月25日观测矮行星Haumea系统,得到29晚共463幅CCD图像.新定心算法确定的光心位置与使用二维高斯定心算法的结果相比具有更好的位置拟合效果.此外,还发现亮卫星Hi’iaka在Jet Propulsion Laboratory (JPL)历表与Institut de Mécanique Céleste et de Calcul des éphémérides (IMCCE)历表中的位置存在较大偏差.

关键词：天体测量学技术:图像处理方法:数据分析柯伊伯带天体:个别:妊神星

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留守初中生抑郁症状对非自杀性自伤行为影响的纵向研究

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中国健康教育 2024年第3期40卷 250-255页

作者：尹斐姜文龙周郁秋杨金伟杨楠哈尔滨医科大学护理学院黑龙江哈尔滨150081 大庆市第三医院黑龙江大庆163712

目的评估留守初中生抑郁症状与非自杀性自伤行为变化趋势,探讨二者发展关系及时序效应。方法通过多阶段分层整群随机抽样,使用儿童抑郁量表(CDS)和青少年非自杀性自伤评定问卷(ANSAQ),对372名留守初中生进行为期1年的3次纵向调查。结... 详细信息

目的评估留守初中生抑郁症状与非自杀性自伤行为变化趋势,探讨二者发展关系及时序效应。方法通过多阶段分层整群随机抽样,使用儿童抑郁量表(CDS)和青少年非自杀性自伤评定问卷(ANSAQ),对372名留守初中生进行为期1年的3次纵向调查。结果留守初中生抑郁症状和非自杀性自伤行为呈线性增长。抑郁初始水平正向预测非自杀性自伤初始水平与增长速率(β=0.473,β=0.577;P0.05)。结论留守初中生抑郁症状和非自杀性自伤行为随时间不断增长,抑郁症状是非自杀性自伤的前因变量,抑郁症状可预测非自杀性自伤发生。

关键词：留守初中生抑郁非自杀性自伤潜变量增长模型交叉滞后模型

Mammals of Gaoligong Mountain in China:Diversity,distribution,and conservation

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Zoological Research(Diversity and Conservation) 2024年第1期1卷 3-19页

作者： Quan Li Xue-You Li Wen-Qiang Hu Wen-Yu Song Shui-Wang He Hong-Jiao Wang Zhe-Chang Hu Meng-Cheng Li Kenneth Otieno Onditi Zhong-Zheng Chen Chang-Zhe Pu Yun Xiong Cai-Hong Rao Fu-You Zhang Chang-Sheng Zuo Xue-long jiang State Key Laboratory of Genetic Resources and Evolution&Yunnan Key Laboratory of Biodiversity and Ecological Conservation of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Gaoligong Mountain Forest Ecosystem Observation and Research Station of Yunnan Province&Dulongjiang Forest Ecosystem Research Station KunmingYunnan 650223China University of Chinese Academy of Sciences Beijing 101408China Vector Laboratory Institute of Pathogens and VectorsYunnan Provincial Key Laboratory for Zoonosis Control and PreventionDali UniversityDaliYunnan 671000China School of Ecology and Environment Anhui Normal UniversityWuhuAnhui 241002China Gongshan Administrative Sub-Bureau of Gaoligongshan National Nature Reserve NujiangYunnan 673500China Fugong Administrative Sub-Bureau of Gaoligongshan National Nature Reserve NujiangYunnan 673400China Baoshan Administrative Bureau of Gaoligongshan National Nature Reserve BaoshanYunnan 678000China Administrative Bureau of Tongbiguan Provincial Nature Reserve DehongYunnan 679300China

Gaoligong Mountain(hereafter,GLGM)is located at the intersection of Myanmar and China’s Yunnan Province and Xizang Zizhiqu,and spans three globally significant biodiversity hotspots:the Himalayas,Indo-Burma,and the Mountains of Southwest *** surveys of mammals in this ecologically important region have a long history,there is no comprehensive systematic checklist and distribution account of the mammals of ***,we compiled a mammal species checklist of GLGM based on thorough field investigations and literature *** also examined specimen collections and applied camera trapping surveys to explore the region’s mammal diversity and distribution *** recorded 212 mammal species in nine orders,33 families,and 119 genera,which accounts for 30.5%of China’s mammal species,and a high proportion of nationally protected(50)and globally threatened(29)*** species richness showed a symmetrical unimodal curve along the elevation gradient,peaking at intermediate elevations(2000 to 2500 m above sea level(asl)),and increasing generally from south to north,slightly higher in the east slope than in the *** analysis and non-metric multidimensional scaling revealed three distinct elevational assemblages(3500 m asl)and significant south-to-north variation,but no substantial differences between the east and west *** GLGM present a unique conservation value due to the high proportions of rare and endangered mammal species,complex faunal composition,high endemism,and being the distribution boundary for many *** study is an important phased account of mammal diversity in GLGM and makes a prospect for future research.

关键词： Biodiversity hotspot Eastern Himalaya Gaoligong Mountain Endemism Mammal conservation Hengduan Mountains

Achievements and challenges of primate conservation in China

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Zoological Research(Diversity and Conservation) 2024年第1期1卷 66-74页

作者： Bao-Guo Li He Zhang Ming Li Xue-long jiang Peng-Fei Fan jiang Zhou Song-Tao Guo Xiao-Guang Qi Jin-Hua Li Ji-Qi Lu Dong-Po Xia Liang-Wei Cui Zuo-Fu Xiang Qi-Hai Zhou Zhi-Pang Huang Cheng-Ming Huang Wen Xiao Hui-Jian Hu Zhi-Xin Zhou Ming-Yong Chen Da-Yong Li Peng-Lai Fan Yin Yang Ru-Liang Pan Shaanxi Key Laboratory for Animal Conservation College of Life SciencesNorthwest UniversityXi’anShaanxi 710069China jiangxi Provincial Key Laboratory of Conservation Biology College of ForestryJiangxi Agricultural UniversityNanchangJiangxi 330045China Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650201China School of Life Sciences Sun Yat-sen UniversityGuangzhouGuangdong 510275China School of Karst Science Guizhou Normal UniversityGuiyangGuizhou 550025China International Collaborative Research Center for Huangshan Biodiversity and Tibetan Macaque Behavioral Ecology Anhui UniversityHefeiAnhui 230601China Institute of Biodiversity and Ecology Zhengzhou UniversityZhengzhouHenan 450001China Key Laboratory for Conserving Wildlife with Small Populations in Yunnan Southwest Forestry UniversityKunmingYunnan 650224China College of Life Sciences and Technology Central South University of Forestry and TechnologyChangshaHunan 410004China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Ministry of Education) Guangxi Normal UniversityGuilinGuangxi 541004China International Centre of Biodiversity and Primate Conservation Centre Dali UniversityDaliYunnan 671003China Guangdong Key Laboratory of Animal Conservation and Resource Utilization Institute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong 510663China School of Life Sciences Yunnan UniversityKunmingYunnan 650500China Key Laboratory of Southwest China Wildlife Resources Conservation(Ministry of Education) China West Normal UniversityNanchongSichuan 637001China Institute of International Rivers and Eco-security Yunnan UniversityKunmingYunnan 650500China School of Human Sciences The University of Western AustraliaPerthWA 6009Australia

The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity *** is home to the most diverse primate species in the Northern hemisphere,which face severe ecological threats due to the expansion of modern agriculture,extensive exploitation and consumption of natural resources,and excessive land development during its transition from an agricultural to a modern *** response,China has implemented various ecological conservation measures,including habitat restoration and *** efforts have made substantial strides in biodiversity conservation,with certain regions witnessing an increase in primate *** the current study,we conducted a systematic review of historical documents and field research data related to Chinese primates,evaluating the endangered status of primate species in *** improvements in the habitats of most primate species and some population growth,many species still face severe threats,including declining and small *** such as the Myanmar snub-nosed monkey(Rhinopithecus strykeri),eastern black crested gibbon(Nomascus nasutus),and Hainan gibbon(***)remain particularly vulnerable due to their limited distribution ranges and extremely small *** scientific data,fragmented information,and not enough studies in conservation biology further compound the ***,there is a notable lack of detailed population monitoring data for species such as the Bengal slow loris(Nycticebus bengalensis),pygmy slow loris(***),Indochinese gray langur(Trachypithecus crepusculus),Shortridge’s langur(***),and capped langur(***),which hinders the development of practical and targeted conservation management ***,for national biodiversity conservation,there is an urgent need for specialized primate surveys,enhancing habitat protection and restoration,and increasing focus on cross-border conse

关键词： Primates Biodiversity Habitat fragmentation Habitat restoration Conservation strategies

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BIM技术在机电工程数字调试中的应用分析

工程与建设 2024年第1期38卷 181-182,229页

作者：徐小龙蒋隆张淇黄金友张艺才中建三局第一建设工程有限责任公司湖北武汉430040 中建三局第一建设安装有限公司湖北武汉430040

随着科学技术的不断进步,建筑信息模型(BIM)技术在工程中的应用越来越广泛。本文以实际工程项目为载体,介绍BIM技术在机电工程数字化调试中的应用,即利用BIM技术来建立整个建筑可视化的三维综合机电管线模型,进行机电管线的碰撞检测、调... 详细信息

随着科学技术的不断进步,建筑信息模型(BIM)技术在工程中的应用越来越广泛。本文以实际工程项目为载体,介绍BIM技术在机电工程数字化调试中的应用,即利用BIM技术来建立整个建筑可视化的三维综合机电管线模型,进行机电管线的碰撞检测、调试,分析BIM技术在机电管综中的重要性。分析结论可为在机电安装工程中强化BIM技术的应用起到更加积极的促进作用。

关键词： BIM技术机电安装工程数字调试应用

熄风活络胶囊HPLC特征图谱建立及11个成分含量测定

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药物分析杂志 2024年第6期44卷 938-945页

作者：谭姣章夏建成周红玲刘阳蒋龙波邓湘俊刘隆基段云峰严建业湖南中医药高等专科学校附属第一医院(湖南省直中医医院) 株洲412000 湖南中医药大学科技创新中心长沙410208 湖南省中药活性物质筛选工程技术研究中心长沙410208

目的:建立熄风活络胶囊的HPLC特征图谱,并测定天麻素、苦杏仁苷、士的宁、羟基红花黄色素A、马钱子碱、芍药苷、阿魏酸、丹酚酸B、隐丹参酮、丹参酮Ⅰ、丹参酮ⅡA的含量。方法:熄风活络胶囊的75%甲醇水提取液,采用Venusil MP C18色谱柱(... 详细信息

目的:建立熄风活络胶囊的HPLC特征图谱,并测定天麻素、苦杏仁苷、士的宁、羟基红花黄色素A、马钱子碱、芍药苷、阿魏酸、丹酚酸B、隐丹参酮、丹参酮Ⅰ、丹参酮ⅡA的含量。方法:熄风活络胶囊的75%甲醇水提取液,采用Venusil MP C18色谱柱(250 mm×4.6 mm, 5μm),以0.1%磷酸水溶液(A)-乙腈(B)作为流动相进行梯度洗脱,体积流量为1.0 mL·min^(-1);柱温为30℃,检测波长为变波长。测定10批熄风活络胶囊特征图谱,标定共有峰并进行归属分析及相似度评价,对采用对照品比对确认的成分进行含量测定。结果:10批熄风活络胶囊特征图谱标定共有峰31个,相似度均大于0.99,归属于12味药材,指认出11个色谱峰。11个成分在各自范围内线性良好(r≥0.999 4),平均加样回收率为99.3%~103.0%,RSD为1.5%~2.4%。结论:所建立的方法灵敏度高,专属性强,HPLC特征图谱结合多成分定量测定能全面地反映其内在质量,可用于熄风活络胶囊的质量控制。

关键词：熄风活络胶囊高效液相色谱法特征图谱相似度分析化学成分

重庆市新型冠状病毒感染疫情流行病学特征及其参数与防控措施评估(2020年)

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国际流行病学传染病学杂志 2024年第1期51卷 33-37页

作者：罗庆龙江熊宇王开发西南大学数学与统计学院重庆400715 重庆市疾病预防控制中心传染病预防控制所重庆400042

目的了解重庆市2020年度SARS-CoV-2感染者流行病学特征,并估计该阶段疫情传播的重要流行病学参数,探究防控措施对新发流行病传播的影响。方法回顾性收集重庆市卫生健康委员会和重庆市疾病预防控制中心2020年重庆市SARS-CoV-2感染者的数... 详细信息

目的了解重庆市2020年度SARS-CoV-2感染者流行病学特征,并估计该阶段疫情传播的重要流行病学参数,探究防控措施对新发流行病传播的影响。方法回顾性收集重庆市卫生健康委员会和重庆市疾病预防控制中心2020年重庆市SARS-CoV-2感染者的数据,采用描述性统计分析方法,对疾病进行流行病学特征分析,构造似然函数,并根据Akaike信息准则估计了潜伏期的最优概率分布。最后基于极大似然思想和贝叶斯框架对基本再生数、有效再生数进行了估计。结果重庆市于2020年1月1日出现首例病例,发病高峰在1月24—26日,2月21日之后无新发病例。渝东北片区地区发病率最高(3.28/10万)。发病人群男女性别比为1.10∶1,总体发病率男性(1.86 /10万)稍高于女性(1.73 /10万)。确诊病例中占比最多的年龄组为45~50岁(91例,91/576),其次是50~55岁(71例,71/576)。潜伏期的最优概率分布为伽马分布,估计均值为7.22 d。重庆市COVID-19疫情初始阶段的基本再生数估计为2.68(2.04,3.44),有效再生数的变化趋势与防控策略的实施密切相关。结论重庆市2020年1—2月全市COVID-19流行曲线呈起病急、收尾快的特点。尽管疫情具有较强的传播性,但定量和定性分析均表明政府采取防控措施及时有效,为将来新发突发传染病防控积累了经验。

关键词：新型冠状病毒感染潜伏期基本再生数有效再生数防控措施

基于环境协调的淮河流域高速公路路线方案评价指标体系及设计方案比选

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工程与建设 2024年第2期38卷 297-300,318页

作者：王博陈菊香姚江龙安徽省交通控股集团有限公司合肥工业大学土木与水利工程学院

在我国高速公路发展的不同阶段,路线选线技术侧重点不同。现阶段,生态环境保护及基本农田耕地保护在路线选择中成为非常重要的影响因素。本文基于绿色公路理念,结合安徽省淮河流域高速公路工程区域生态环境特征,建立了包含技术指标、环... 详细信息

在我国高速公路发展的不同阶段,路线选线技术侧重点不同。现阶段,生态环境保护及基本农田耕地保护在路线选择中成为非常重要的影响因素。本文基于绿色公路理念,结合安徽省淮河流域高速公路工程区域生态环境特征,建立了包含技术指标、环境指标、安全指标和社会指标的4项一级指标和18项二级指标的路线设计评价指标体系,采用改进的熵权-TOPSIS法对高速公路工程的路线设计方案进行评价比选,为高速公路路线方案比选提供参考与借鉴。

关键词：公路工程路线评价指标方案比选

Experimental Study on Wire Melting Control Ability of Twin-Body Plasma Arc

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 184-194页

作者： Ruiying Zhang Fan jiang long Xue School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Beijing Academy of Safety Engineering and Technology Beijing 102617China College of Mechanical and Energy Engineering Beijing University of TechnologyBeijing 100124China

The twin-body plasma arc has the decoupling control ability of heat transfer and mass transfer,which is beneficial to shape and property control in wire arc additive *** this paper,with the wire feeding speed as a characteristic quantity,the wire melting control ability of twin-body plasma arc was studied by adjusting the current separation ratio(under the condition of a constant total current),the wire current/main current and the position of the wire in the arc axial *** results showed that under the premise that the total current remains unchanged(100 A),as the current separation ratio increased,the middle and minimum melting amounts increased approximately synchronously under the effect of anode effect power,the first melting mass range remained constant;the maximum melting amount increased twice as fast as the middle melting amount under the effect of the wire feeding speed,and the second melting mass range was *** the wire current increased,the anode effect power and the plasma arc power were both factors causing the increase in the wire melting amount;however,when the main current increased,the plasma arc power was the only factor causing the increase in the wire melting *** average wire melting increment caused by the anode effect power was approximately 2.7 times that caused by the plasma arc *** minimum melting amount was not affected by the wire-torch distance under any current separation ratio *** the current separation ratio increased and reached a threshold,the middle melting amount remained constant with increasing wire-torch *** the current separation ratio continued to increase and reached the next threshold,the maximum melting amount remained constant with the increasing wire-torch *** effect of the wire-torch distance on the wire melting amount reduced with the increase in the current separation *** this study,the decoupling mechanism and ability of this innovative

关键词： Twin-body plasma arc Melting control ability Melting amount Current separation ratio