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基于改进遗传算法的最大2维熵图像分割

激光技术 2019年第1期43卷 119-124页

作者：李丽宏华国光河北工程大学信息与电气工程学院邯郸056038

为了解决传统最大2维熵分割算法计算量大、耗时较多等缺陷,提出一种基于改进遗传算法的最大2维熵图像分割法。通过对遗传算法变异操作方式进行改进,提高遗传算法寻找最大2维熵分割阈值的速度,加速分割算法对图像的分割,并进行了仿真实... 详细信息

为了解决传统最大2维熵分割算法计算量大、耗时较多等缺陷,提出一种基于改进遗传算法的最大2维熵图像分割法。通过对遗传算法变异操作方式进行改进,提高遗传算法寻找最大2维熵分割阈值的速度,加速分割算法对图像的分割,并进行了仿真实验验证。结果表明,改进模型的运行时间被压缩到了0.95s,远远低于传统的最大2维熵分割法。改进的分割方法实现了分割效率的提高,同时也保证了图像的分割精度。

关键词：图像处理最大2维熵遗传算法变异操作

Spatiotemporal Measurement of Regional Expansion in Changsha-Zhuzhou-Xiangtan Metropolitan Area Based on Nighttime Light Data

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Journal of Geographic Information System 2020年第3期12卷 202-220页

作者： Jian Zheng guoguang Wang hua Wang School of Architecture State Key Laboratory of Subtropical Building Science South China University of Technology Guangzhou China School of Architecture and Art Central China University Changsha China

The research purpose is to accurately reveal the temporal and spatial law of the urban expansion of Changsha-Zhuzhou-Xiangtan, one of the seven major urban agglomeration areas in China, and provide decision-making basis for the future urban construction land layout and regional development policy-making. Based on the night lighting data (DMSP/OLS), this paper extracts the boundary of the urban construction land of Changsha-Zhuzhou-Xiangtan urban agglomeration from 1993 to 2017, and quantitatively studies the spatial and temporal characteristics of the expansion of the metropolitan area in the past 25 years according to the methods of spatial expansion analysis, center of gravity migration measurement, landscape pattern index, spatial autocorrelation, etc. The results show that: 1) it is scientific and feasible to extract urban agglomeration construction land by the method of auxiliary data comparison for the study of urban expansion;2) the expansion of regional space in Changsha-Zhuzhou-Xiangtan metropolitan area shows a trend of “weakening first and strengthening later”. The construction land keeps increasing, and the expansion form gradually changes from extensive type to intensive type;3) the center of gravity of the metropolitan area fluctuated and repeated in part during the past 25 years, but it was always located in the municipal district of Changsha city. The eastern region, mainly Changsha city, was still the core area of urban agglomeration expansion;4) strengthening the territorial space protection and control of ecological green core in the metropolitan area is a key measure for the high-quality development of urban agglomeration.

关键词： Changsha-Zhuzhou-Xiangtan Spatial Expansion Nighttime Light Data Metropolitan Area Control Scenario

Association between low ambient temperature during pregnancy and adverse birth outcomes: A systematic review and meta-analysis

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中华医学杂志(英文版) 2023年第19期136卷 2307-2315页

作者： Ruan Tiechao Yue Yan Lu Wenting Zhou Ruixi Xiong Tao Jiang Yin Ying Junjie Tang Jun Shi Jing Wang hua Xiao guoguang Li Jinhui Qu Yi Mu Dezhi Department of Pediatrics West China Second University Hospital Sichuan University Chengdu Sichuan China Key Laboratory of Obstetrics and Gynecologic and Pediatric Diseases and Birth Defects of the Ministry of Education Sichuan University Chengdu Sichuan China Department of General Practice West China Hospital Sichuan University Chengdu Sichuan China

Background: Extreme temperature events, including extreme cold, are becoming more frequent worldwide, which might be harmful to pregnant women and cause adverse birth outcomes. We aimed to investigate the association between exposure to low ambient temperature in pregnant women and adverse birth outcomes, such as preterm birth, low birth weight, and stillbirth, and to summarize the evidence ***: Relevant studies were searched in PubMed, Cochrane, and Embase electronic databases until November 2021. Studies involving low ambient temperature, preterm birth, birth weight, and stillbirth were included. The guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses were followed to conduct this study risk of bias and methods for data ***: A total of 34 studies were included. First, pregnant women exposed to low ambient temperature had an increased risk of preterm birth (risk ratio [RR] 1.08; 95% confidence interval [CI] 1.04–1.13). Subgroup analyses revealed that exposure during late pregnancy was more likely to induce preterm birth. In addition, only pregnant women exposed to <1st percentile of the mean temperature suffered increased risk of preterm birth. Moreover, pregnant women living in medium or hot areas were more prone to have preterm births than those in cold areas when exposed to low ambient temperatures. Asians and Blacks were more susceptible to low ambient temperatures than Caucasians. Second, pregnant women exposed to low ambient temperature had an increased risk of low birth weight (RR 1.07; 95% CI 1.03–1.12). Third, pregnant women had an increased risk of stillbirth while exposed to low ambient temperature during the entire pregnancy (RR 4.63; 95% CI 3.99–5.38).Conclusions: Exposure to low ambient temperature during pregnancy increases the risk of adverse birth outcomes. Pregnant women should avoid exposure to extremely low ambient temperature (<1st percentile of the mean temperature), especially in their

关键词： Ambient temperature Pregnancy Preterm birth Birth weight Stillbirth

短波紫外反射照相显现玻璃表面潜在汗液油脂指印

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中国刑警学院学报 2004年第1期 63-64页

作者：庄华潘国光中国刑警学院

介绍了利用全波段 CCD 相机对五种玻璃表面的汗液和三种油脂指印进行短波紫外反射照相实验的结果,分析纹线黑白颜色的成因,探索了对玻璃表面汗液和油脂指印的短波紫外反射照相的技术方法和良好前景。

关键词：玻璃照相指印紫外反射

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LIMS在水质检测实验室的应用

净水技术 2005年第6期24卷 53-55页

作者：陈国光王近李华上海供水调度监测中心上海200002 北京泰立华电子技术有限公司北京100000

文章对实验室信息管理系统(LIMS)的功能,特点及其在上海水质监测站运行情况、运行效果做了介绍。

关键词：实验室信息管理系统水质检测实验室质量管理手册

某220kV变电站弹簧机构断路器拒分事件分析

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高压电器 2023年第10期59卷 232-239页

作者：徐华陈孝信李国广李斐然徐冬梅谢凌东赵鲁臻国网浙江省电力有限公司杭州310007 国网浙江省电力有限公司电力科学研究院杭州310014 国网浙江省电力有限公司绍兴供电公司浙江绍兴312000 国网浙江省电力有限公司宁波供电公司浙江宁波315012

针对一起220 kV变电站内弹簧机构断路器拒分事件展开分析,结合弹簧机构的机械结构和工作原理,梳理引发机械故障的主要风险因素和排查流程。通过部件检测、模拟试验和受力分析明确了故障发生原因,提出后续质量管控的建议措施,为弹簧机构... 详细信息

针对一起220 kV变电站内弹簧机构断路器拒分事件展开分析,结合弹簧机构的机械结构和工作原理,梳理引发机械故障的主要风险因素和排查流程。通过部件检测、模拟试验和受力分析明确了故障发生原因,提出后续质量管控的建议措施,为弹簧机构故障分析和质量管控提供参考。

关键词：弹簧机构断路器拒分润滑脂掣子摩擦

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急性坏死性胰腺炎患者炎性病灶分区的初探

中华肝胆外科杂志 2024年第6期30卷 445-450页

作者：刘喜武李国光刘毅蔡翊姚沣轩华鸿基隆艳飞湖南省人民医院(湖南师范大学附属第一医院)胰脾外科长沙410005 湖南师范大学胰腺疾病转化医学研究所长沙410005

目的:结合胰周膜解剖结构理论,初步探索急性坏死性胰腺炎患者炎性病灶的分区及其对疾病转归的影响。方法:回顾性分析湖南省人民医院2021年1月1日至2022年6月30日收治的197例急性坏死性胰腺炎患者的临床资料,其中男性133例,女性64例,年龄... 详细信息

目的:结合胰周膜解剖结构理论,初步探索急性坏死性胰腺炎患者炎性病灶的分区及其对疾病转归的影响。方法:回顾性分析湖南省人民医院2021年1月1日至2022年6月30日收治的197例急性坏死性胰腺炎患者的临床资料,其中男性133例,女性64例,年龄(47.2±13.3)岁。收集患者的一般资料、胰腺炎特征资料、影像资料等,结合胰周膜解剖结构理论对炎性病灶进行分区。以门诊复查及电话的方式进行随访。根据预后情况将患者分为两组:将术后并发多器官功能衰竭、严重局部并发症或死亡的患者纳入预后不良组( n=93),将未出现上述不良预后的患者纳入非预后不良组( n=104)。多因素logistic回归分析预后不良的影响因素。绘制受试者工作特征(ROC)曲线评估受累区域个数对预后不良的预测效能。结果:胰周结构的炎性病灶被划分为13个分区:小网膜囊区域、胰头十二指肠区域、左肾前区域、右肾前区域、左肾后方区域、右肾后方区域、左肾周脂肪囊区域、右肾周脂肪囊区域、左侧侧腹壁区域、右侧侧腹壁区域、左侧盆腔侧壁区域、右侧盆腔侧壁区域、其他区域。预后不良组和非预后不良组患者的体质量指数、胰腺坏死面积及炎性病灶区域个数间差异具有统计学意义(均 P<0.05)。多因素logistic回归分析结果显示,体质量指数高( OR=1.723,95% CI:1.457~2.038, P<0.001)、胰腺坏死面积≥50%( OR=3.221,95% CI:1.073~9.668, P=0.037)及炎性病灶区域个数多( OR=1.388, 95% CI:1.110~1.735, P=0.004)的急性坏死性胰腺炎患者,预后不良的风险高。经ROC曲线分析,炎性病灶区域个数预测急性坏死性胰腺炎患者出现不良预后的最佳截断值为5.5,曲线下面积为0.747(95% CI:0.680~0.815),灵敏度和特异度分别为0.387和0.962。结论:胰周膜解剖结构的存在使得急性坏死性胰腺炎患者炎性病灶存在相对固定的分区,且炎性病灶区域个数与不良预后相关。

关键词：胰腺炎,急性坏死性炎性病灶膜解剖分区筋膜