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基于快速方向预测的高分辨率遥感影像压缩

光学精密工程 2013年第8期21卷 2095-2102页

作者：张立保丘兵昌北京师范大学信息科学与技术学院北京100875 北京师范大学遥感科学国家重点实验室北京100875

针对传统的自适应方向提升小波变换(ADL-DWT)算法在高分辨率遥感影像压缩中计算复杂度过高的问题,提出一种新的基于方向预测的提升小波变换(DP-LWT)算法,实现了高分辨率遥感影像的快速、高效压缩。新算法首先将高分辨率遥感影像分为若... 详细信息

针对传统的自适应方向提升小波变换(ADL-DWT)算法在高分辨率遥感影像压缩中计算复杂度过高的问题,提出一种新的基于方向预测的提升小波变换(DP-LWT)算法,实现了高分辨率遥感影像的快速、高效压缩。新算法首先将高分辨率遥感影像分为若干不重叠子块,然后采用梯度算子快速预测遥感影像中每个图像块的最佳提升方向,并沿着最佳预测方向插值完成方向提升小波变换,最后进行多级树集合分裂(SPIHT)编码。实验结果表明,新算法有效削弱了遥感影像各子带中非水平与非垂直方向的高频系数;与传统自适应方向提升小波变换相比,在重建高分辨率遥感影像峰值信噪比基本相同的情况下,有效减少了小波变换中方向预测的计算复杂度。

关键词：遥感图像处理图像压缩小波变换自适应方向提升方向预测

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乙型肝炎病毒X基因克隆及其表达

中南大学学报（医学版） 2005年第5期30卷 525-528页

作者：唐世刚杨兵厂中南大学湘雅三医院感染病科长沙410013

目的:构建乙型肝炎病毒X基因原核表达载体,并诱导其表达。方法:从乙肝病人血清中提取HBVDNA;以带有EcoRI和HindⅢ酶切位点的引物,用PCR方法扩增X基因;而后定向克隆到原核表达载体pMAL-C2X上,经酶切鉴定和序列分析;以IPTG诱导X融合蛋白... 详细信息

目的:构建乙型肝炎病毒X基因原核表达载体,并诱导其表达。方法:从乙肝病人血清中提取HBVDNA;以带有EcoRI和HindⅢ酶切位点的引物,用PCR方法扩增X基因;而后定向克隆到原核表达载体pMAL-C2X上,经酶切鉴定和序列分析;以IPTG诱导X融合蛋白的表达。结果:PCR扩增显示有类似HBVX基因片断大小的条带;构建的原核表达重组体PMAL-C2X-HBV-X经酶切有相应大小的的基因插入片断,序列分析证实为正确的有完整读码框的X基因;这一重组体在IPTG诱导下有相应大小的X融合蛋白表达。结论:成功构建了HBVX基因原核表达重组体pMAL-C2X-HBVX;在IPTG的诱导下,该重组体在大肠杆菌中可表达X融合蛋白,为进一步纯化HBVX蛋白和研究其生物学作用奠定了基础。

关键词：乙型肝炎病毒克隆乙型肝炎病毒X蛋白表达

Diagnostic capacity of skin tumor artificial intelligence-assisted decision-making software in real-world clinical settings

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Chinese Medical Journal 2020年第17期133卷 2020-2026页

作者： Cheng-Xu Li Wen-Min Fei chang-bing Shen Zi-Yi Wang Yan Jing Ru-Song Meng Yong Cui Department of Dermatology China-Japan Friendship HospitalBeijing 100029China Graduate School Peking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China Hinda and Arthur Marcus Institute for Aging Research Hebrew SeniorLife and Harvard Medical SchoolBostonMAUSA Department of Dermatology The First Affiliated HospitalAnhui Medical UniversityHefeiAnhui 230032China Department of Dermatology Specialty Medical Center of the Air ForceChinese People’s Liberation ArmyBeijing 100142China

Background:Youzhi artificial intelligence(AI)software is the AI-assisted decision-making system for diagnosing skin *** high diagnostic accuracy of Youzhi AI software was previously validated in specific *** objective of this study was to compare the performance of diagnostic capacity between Youzhi AI software and dermatologists in real-world clinical ***:A total of 106 patients who underwent skin tumor resection in the Dermatology Department of China-Japan Friendship Hospital from July 2017 to June 2019 and were confirmed as skin tumors by pathological biopsy were *** and clinical images of 106 patients were diagnosed by Youzhi AI software and dermatologists at different dermoscopy diagnostic *** primary outcome was to compare the diagnostic accuracy of the Youzhi AI software with that of dermatologists and that measured in the laboratory using specific data *** secondary results included the sensitivity,specificity,positive predictive value,negative predictive value,F-measure,and Matthews correlation coefficient of Youzhi AI software in the ***:The diagnostic accuracy of Youzhi AI software in real-world clinical settings was lower than that of the laboratory data(P<0.001).The output result of Youzhi AI software has good stability after several *** AI software diagnosed benign and malignant diseases by recognizing dermoscopic images and diagnosed disease types with higher diagnostic accuracy than by recognizing clinical images(P=0.008,P=0.016,respectively).Compared with dermatologists,Youzhi AI software was more accurate in the diagnosis of skin tumor types through the recognition of dermoscopic images(P=0.01).By evaluating the diagnostic performance of dermatologists under different modes,the diagnostic accuracy of dermatologists in diagnosing disease types by matching dermoscopic and clinical images was significantly higher than that by identifying dermoscopic and clinical images in

关键词： Artificial intelligence Skin tumor Diagnostic accuracy

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色高斯噪声驱动双稳系统的多重随机共振研究

物理学报 2011年第6期60卷 162-167页

作者：张晓燕徐伟周丙常西北工业大学应用数学系西安710072

研究了由色关联乘性和加性色噪声作用下的双稳系统的随机共振问题,在绝热近似条件下得到了信噪比的表达式.通过分析所得的初始条件为x(0)=x+时的信噪比,发现了单随机共振和多重随机共振现象;分析了噪声强度、噪声关联时间和关联强度对... 详细信息

研究了由色关联乘性和加性色噪声作用下的双稳系统的随机共振问题,在绝热近似条件下得到了信噪比的表达式.通过分析所得的初始条件为x(0)=x+时的信噪比,发现了单随机共振和多重随机共振现象;分析了噪声强度、噪声关联时间和关联强度对系统信噪比的影响.

关键词：多重随机共振信噪比双稳模型色关联色噪声

Feasibility Study of Enforcing Immunization Certificate Check Before Primary School or Kindergarten Enrollment in Guizhou Province, China

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Biomedical and Environmental Sciences 2007年第5期20卷 357-365页

作者： LI SHENG SHU-YAN ZUO JING XIE YA-LI QI YI-bing TONG GUANG-PENG TANG JUN ZHOU DA-YONG ZHANG chang-bing LONG WEN DU ZI-JIAN FENG Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100005 China Chinese Center for Disease Control and Prevention Beijing 100050 China Department of Public Health and Primary Care University of Cambridge Cambridge CB2 2SR UK Medical College Preventive Department Beihua University Jilin 132013 Jilin China Center for Diseases Control and Prevention of Guizhou Province Guiyang 550000 Guizhou China Center for Diseases Control and Prevention of Qiandongnan District Kaili 510800 Guizhou China

Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducted. The multi-stage and cluster sampling approach was adopted for the quantitative part of the study. A questionnaire was designed and 996 children and their keepers were interviewed. Principals, doctors or teachers of the primary schools, directors and child care nurses of kindergarten, and staff of immunization agencies were invited to take part in 12 focus group discussions; meanwhile, face-to-face individual in-depth interviews with 16 officials of the Health, Education and Governmental Departments at various levels were conducted. Results The total number of subjects was 996. 16.7% of the children in the study completed all the procedures of the National Immunization Programme. 34.3% of them had immunization certificates while the remainder 44.7% registered in immunization agencies. Factors, including the migrant children, doubt about vaccine efficiency, mother’s occupation and educational background, knowledge of the National Immunization Programme on targeted vaccines, played an important role in obtaining or not immunization certificates. 95% of the keepers interviewed thought the immunization certificates were useful; 94.8% of them considered the check was critical while only 3.6% of them thought it unnecessary. The first reason from those who found it unnecessary was that they feared that repeated immunization might affect their children’s health. The second reason was the cost of immunization, which some of them could not afford to pay. However, the Health Department expressed a favorable attitude to the checking scheme. Though the Education Department agreed that the scheme was essential, they worried that it would affect the enrollment *** In spite of the difficulty in administering immunization certificate check, the effort woul

关键词： Immunization certificate check Impacting factors Sampling research Quantitative study Qualitative study Enrollment rate

中国城市化影响政府公共支出的理论分析及实证

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当代经济科学 2009年第3期31卷 16-20页

作者：陈昌兵中国社会科学院经济研究所北京100836

工业化向城市化转变的过程中,中国政府的目标发生了变化。工业化时期,政府动员一切可利用的资源发展经济,而在城市化阶段,政府转向福利支出目标。这一转变表现为经济建设费支出比重减小而公共财政支出比重不断增大。本文分析了中国城市... 详细信息

工业化向城市化转变的过程中,中国政府的目标发生了变化。工业化时期,政府动员一切可利用的资源发展经济,而在城市化阶段,政府转向福利支出目标。这一转变表现为经济建设费支出比重减小而公共财政支出比重不断增大。本文分析了中国城市化使政府公共支比重增大,并进行了实证分析。城市化率每增加1个百分点,公共财政支出比重就增加0.6293个百分点,且公共财政支出比重随收入差距扩大而增大。

关键词：城市化政府目标公共财政支出比重 VECM

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数字动画艺术与体验美学

山东社会科学 2010年第4期 53-56,60页

作者：邱秉常华中科技大学新闻与信息传播学院湖北武汉430074

以体验哲学为基础的西方当代体验美学,是以批判一切传统哲学的思维方式为前提的,它要消除主客体的简单对立,确切地说,就是要消除审美客体化的思维。体验美学认为审美对象既是审美体验的对象,又是审美体验的产物。利普斯说:"我感到活动... 详细信息

以体验哲学为基础的西方当代体验美学,是以批判一切传统哲学的思维方式为前提的,它要消除主客体的简单对立,确切地说,就是要消除审美客体化的思维。体验美学认为审美对象既是审美体验的对象,又是审美体验的产物。利普斯说:"我感到活动并不是对着对象,而是就在对象里面,我感到欣喜,也不是对着我的活动,而是就在我的活动里面。我在我的活动里面感到欣喜或幸福。"体验美学和体验观念对艺术创作有很大影响。对于动画创作和欣赏来说,体验美学是一个不可忽视的因素。而从体验美学考查数字动画这一新兴艺术类型将是一个新的视觉。

关键词：数字动画艺术体验美学审美客体对象