1,313 research outputs found

    Study on Ensemble Algorithm for Multi-class Gene Microarray Datasets

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    集成学习是当前机器学习领域的一个研究热点,具体到多分类问题,旨在通过一组差异的分类器共同解决起初的多分类问题,然后经过大多数投票等策略将各个分类器的输出结果进行融合。集成多分类算法相比于单个的优秀分类器往往性能上更准确、更稳定,同时还具有更强的泛化能力。在解决多分类问题时,基于纠错输出编码算法(ECOC)。这是解决多分类问题的一种灵活、高效的算法框架,关键要点是将多分类转变为多个二分类问题。此外,遗传规划算法可用于解决二分类问题,通过进化计算得到准确的分类规则。本文在已有的研究基础上,对基因微阵列数据的集成多分类学习进行了理论探索和实践。 本文主要围绕着集成多分类算法,应用于基因微阵列数据的...Ensemble learning is a current research focus in the field of machine learning. It applies a set of diverse classifiers together in order to solve the original task as specific to multi-class classification problems and fuses the output of each classifier through majority voting. Multi-class classification ensemble algorithm is more accurate and more stable than an excellent classifier, and has gr...学位:工学硕士院系专业:软件学院_软件工程学号:2432012115229

    Efficient Simulation Methods for Reinforced Concrete Columns with Encased Steel in High-rise Building Structures

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    型钢混凝土柱在建筑结构中往往是主要的承重构件之一,使用合适的数值模型分析其力学性能对高层结构抗震分析有重要的意义。本文综述了目前文献中已有的低含钢率恢复力模型相关研究,分析了其理论、计算流程和算法,并在通用有限元软件OpenSees中编程实现。本文详细推导了模型中基本参数的确定方法,并用于模拟实际高层建筑结构中的型钢混凝土柱。首先,本文用恢复力模型模拟了单根型钢混凝土柱的试验,通过对比验证了模型的精度,研究了其计算效率。其次,本文将恢复力模型用于理想32层高层结构中的单排型钢混凝土构件静、动力分析中。根据与纤维模型计算结果的对比,证明使用恢复力模型分析高层结构中的局部构件抗震性能时较传统的纤维...The steel reinforced concrete column plays an essential role in the structural analysis. Therefore, choosing a suitable simulation method for these components is of significant importance. In this background, the thesis reviews a resilience model for the reinforced concrete column with low ratios encased steel, studies the calibration method for the model parameters, designs the flowcharts of the ...学位:工学硕士院系专业:建筑与土木工程学院_结构工程学号:2532013115180

    Environmental risk assessment of intensive animal production in Jiulong River Watershed

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    在G IS支持下采用养分收支平衡法对九龙江流域规模化生猪养殖的环境风险进行评价。规模化养殖污染负荷在不同类型养殖场的分配、空间分布规律以及规模化养殖的环境风险评价结果表明:规模化养猪业年产粪尿量达107万t,以小型规模化养殖场产生的污染负荷最高;整体来看,规模化生猪养殖的环境风险不大,但由于养殖场的地理分布集中,造成近郊区域规模化养殖的环境风险极高;由于过多施用化肥,中远郊规模化养殖粪尿未得到合理利用而流失。位于水系附近的养殖场对水体影响较大,根据“福建省畜禽养殖污染防治管理办法”,为减少规模化生猪养殖对九龙江水质的直接威胁,需搬迁主要支流沿岸1 km范围内的规模化养猪场250个。 【英文摘要】 With the rapid growth in the number and size of intensive livestock enterprises in China,livestock waste in a huge amount has become one of the main sources of water pollution.Environmental risk assessment of the intensive animal production in the Jiulong River Watershed was conducted with the aid of GIS and the nutrient balance method.The findings of the study of spatial distribution of pollution loads and the environmental risk assessment show that a total of 1 070 000 tons of manure is produced annually ...福建省重大科技攻关项目(2002H009

    Synthetic Study towards Periconiasin A

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    具有生理活性的天然产物不仅是药物学家研究的对象,而且一直以来都备受有机合成化学家的关注。数据统计,1981年初至2014年底这34年间,所有新批准的药物中有46%药物来源与天然产物有关,而抗肿瘤药物的比例更是高达57%,可见天然产物对于新药研发具有重大意义。本论文以高效的策略对具有良好生理活性的杂合天然产物PericoniasinA进行不对称全合成研究。 细胞松弛素类化合物PericoniasinA是2013年由中国医学科学院药物研究所戴均贵研究员等人从刺果番荔枝内生菌Periconiasp.F-31的次级代谢产物中分离得到的一种杂合天然产物。本文中的杂合天然产物是指由两种或更多不同的基本代...Biologically active natural products attract the attention not only pharmacologists but also from synthetic organic chemists. It was showed that 46% of all newly approved drugs between 1981 and 2014 are related to natural products. Furthermore, as high as 57% of new antitumor drugs in the same period are natural products or their derivatives. It means natural products are a significant resource fo...学位:理学硕士院系专业:化学化工学院_有机化学学号:2052013115158

    Behind Masks: Zeng Fanzhi

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    This is a catalog published by Hanart T Z Gallery in 1995. It consists of three articles by Chang Tsong-zung, Li Xianting, and Pi Daojian respectively, in both Chinese and English. The artist\u27s works of the early 1990s are published, including the Hospital Triptych, the Mask Series, and others. A biography of the artist is on the last page (Zhuocheng Jiang \u2726)https://digital.kenyon.edu/zhoudocs/1419/thumbnail.jp

    Preliminary Studies of Molecular Simulation on the Liquid Crystal ehaviors and Glass Transition Temperatures of N-benzyl Chitosan Derivatives

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    壳聚糖结构单元中含有-NH2和-OH,因此可对它进行多种化学修饰,这些丰富的化学修饰方法为研究壳聚糖及其衍生物的液晶性提供了很好的条件。利用它进行分子量、取代度和取代基大小等结构因素对溶致液晶行为影响的研究已先后报道,但取代基上特征官能团的位置变化(羟基在苯环的邻、间、对位上)对其溶致液晶性的影响的研究还尚未见有报道。本文拟通过实验合成一系列取代基上特征官能团的位置发生变化的壳聚糖衍生物,对其溶致液晶性进行研究,并通过分子模拟的手段,研究壳聚糖衍生物结构与性质的关系。根据高分子链段的化学结构组成来预测高分子物质的各种性质,对在工业应用中如何进行选择、改性及设计高分子产品具有重要意义。 本文采...The structure unit of chitosan contains-NH2 and-OH,it can be a variety of chemical modification,such a wealth of chemical modification methods provide a very good condition for the study of the liquid crystalline property of chitosan and its derivatives. Researchs use it to study the impact of molecular weight, degree of substitution, substituent size and other structural factors to the lyotropi...学位:理学硕士院系专业:材料学院材料科学与工程系_高分子化学与物理学号:2072006115206

    Study on Crime of Medical Accident

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    近年来医疗事故大量涌现,正确认定医疗事故罪对于解决医患纠纷,缓和医患矛盾,构建和谐社会具有重要意义。本文的主体部分分为三章,第一章是概述,主要是阐述了医疗事故的定义,简介国外有关医疗事故罪的立法情况,并简要回顾我国有关医疗事故的立法沿革,目的在于通过对医疗事故犯罪立法历史的考察,指出我国医疗事故罪罪名的统一和量刑的明确经历了漫长的历史。第二章是医疗事故罪的犯罪构成研究,该章是本文的主要内容,重点研究医疗事故罪的主观方面与客观方面。文章在分析了学界不同见解的基础上,结合我国的实际情况,在第一节里阐述了医疗事故罪的主体,认为应当是卫生技术人员,不包括医疗行政管理人员与后勤服务人员。在第二节里研究了...Medical accidents have taken place constantly in recent years. Establishing exactly on crime of medical accidents plays an important role on resolving issues between doctors and patients, easing contradiction between doctors and patients, constructing harmonious society. The main body of this thesis includes three chapters. The content of the first chapter of this thesis is the summary to crime of...学位:法律硕士院系专业:法学院法律系_法律硕士(JM)学号:X200512017

    Design and Synthesis of Protein Kinase A’s Inhibitors and their other Applications

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    催化蛋白的可逆磷酸化,调节着细胞信号转导、细胞分化和细胞生长等几乎所有的生命活动过程,是一种普遍的重要调节机制。蛋白质在蛋白激酶作用下发生磷酸化,在磷酸酶的作用下去磷酸化。在人类中,已发现有518种蛋白激酶。蛋白激酶A(PKA)作为第一个最早被解析的激酶晶体,由于其结构及性质比较清楚,已经成为人们研究蛋白激酶家族的最佳切入点。本文主要致力于蛋白激酶A含磷抑制剂的设计,合成,并以蛋白激酶A为模板,对我们提出的蛋白激酶磷酰基转移“排球”机理进行初步的理论研究,最后对合成的系列化合物做了拓展应用研究。 我们建立了基于Autodock以及Dock对接的蛋白激酶A抑制剂的虚拟筛选平台,并用于抑制剂的筛...Protein reversible phosphorylation, an important regulatory mechanism in general, plays a crucial role in almost all of the life process such as cell signal transduction, differentiation and cell growth. All the proteins are phosphorylated by protein kinase family, and dephosphorylated by phosphatases. Thus far, 518 kinds of protein kinases have been found in human beings. Protein kinase A (cAMP-d...学位:理学博士院系专业:化学化工学院化学系_化学生物学学号:2052006015327

    Functional expression of SCN5A mutation R1628Q associated with Brugada syndrome

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    目的 体外构建含R1628Q突变的人心脏钠离子通道α亚基真核表达载体pHL-hH1-R1628Q。研究R1628Q突变对钠通道电生理性质的影响,阐明Brugada综合征的发病机制,为疾病的基因诊断和分子治疗提供新的思路。 方法 设计带突变位点的引物,以含有人心脏钠离子通道cDNA的质粒为模板经重叠延伸PCR法体外定点诱变,构建R1628Q突变型人心脏钠离子通道真核表达载体。经酶切和DNA测序验证后与心脏钠离子通道β1亚基质粒pEGFP-N3-SCN1B瞬时共同转染到HEK293,48小时后全细胞记录钠通道的电生理特性。 结果 1.DNA测序证实突变质粒pHL-hH1-R1628Q构建...Objective To explore the functional effect of R1628Q mutation on SCN5A,we construct human cardiac sodium channel alpha subunit cDNA(hH1) mutated recombinant pHL-hH1-R1628Q via site-directed mutagenesis in vitro, and study the current and electrophysiological properties of the sodium channel using patch-clamp whole-cell recording in HEK293 cell into which the hH1-WT or hH1-R1628Q is transfected. T...学位:医学硕士院系专业:医学院_内科学学号:2452010115328
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