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基于信息粒度的不完备信息系统空值补齐算法

小型微型计算机系统 2011年第4期32卷 752-756页

作者：张霞储尚军许鸣珠河北经贸大学河北石家庄050061 北京科技大学信息工程学院北京100083 石家庄铁道大学机械工程学院河北石家庄050043

在现实世界中,不完备信息系统大量存在的,信息系统中空值的存在大大增加了信息表的不确定性,信息表无法产生更多潜在的有价值规则.处理不完备信息表的一种做法是先将空值补齐再提取规则,常用的空值补齐算法通常都是根据同属性其他值出... 详细信息

在现实世界中,不完备信息系统大量存在的,信息系统中空值的存在大大增加了信息表的不确定性,信息表无法产生更多潜在的有价值规则.处理不完备信息表的一种做法是先将空值补齐再提取规则,常用的空值补齐算法通常都是根据同属性其他值出现的频率高低估计空值,但是此方法不一定能保证规则的一致性.本文提出一种基于信息粒度的空值补齐方法GRCC,首先根据定义的信息粒度选择信息粒度最大的列,然后由相容类产生空值的属性值范围,最后利用MDL准则确定遗漏项的属性值,如此逐列进行填充直到完成全部信息表的补齐.经过实验,GRCC算法补齐的信息表比其它补齐方法产生的信息表产生更多高可信度和高支持度的规则,降低了信息表的不确定性.

关键词：不完备信息系统空值补齐信息粒度相容类最小描述长度

社区老年男性对良性前列腺增生症知晓率的调查分析

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中国全科医学 2010年第17期13卷 1837-1839页

作者：徐明曦达骏王忠上海交通大学医学院附属第九人民医院上海市200011

目的探讨社区老年男性对良性前列腺增生症的知晓情况,为社区良性前列腺增生症的治疗提供较为准确的理论依据。方法 2008年4月—2009年4月,对在上海市黄浦区半淞园社区卫生中心就诊的年龄≥60岁的360名老年男性进行问卷调查,利用统计软... 详细信息

目的探讨社区老年男性对良性前列腺增生症的知晓情况,为社区良性前列腺增生症的治疗提供较为准确的理论依据。方法 2008年4月—2009年4月,对在上海市黄浦区半淞园社区卫生中心就诊的年龄≥60岁的360名老年男性进行问卷调查,利用统计软件进行分析。结果 360名老年男性以60～69岁者最多,共215例,占59.7%。共140名(占38.9%)老年男性对良性前列腺增生症的知晓率评分为"中"。不同文化水平老年男性对良性前列腺增生症的知晓率差异有统计学意义(P<0.05)。结论文化程度的高低是决定老年男性对良性前列腺增生症知晓程度的因素之一。社区医疗单位应加强对良性前列腺增生症的健康宣教活动,以文化程度较低的老年男性为宣教重点,从而有效预防和治疗良性前列腺增生症。

关键词：前列腺增生社区卫生服务问卷调查老年人

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带箝位辅助谐振支路的改进型变换器研究

电力电子技术 2006年第3期40卷 20-23页

作者：王惠庆徐明尹斌河海大学江苏南京210098

移相控制零电压全桥变换器利用变压器漏感和开关管的寄身电容可实现开关管的零电压开关,为了抑制整流输出寄生振荡,可以在初级加入一个谐振电感和两个箝位二极管构成辅助谐振支路,本文将辅助谐振支路与变压器交换位置,使辅助支路与超前... 详细信息

移相控制零电压全桥变换器利用变压器漏感和开关管的寄身电容可实现开关管的零电压开关,为了抑制整流输出寄生振荡,可以在初级加入一个谐振电感和两个箝位二极管构成辅助谐振支路,本文将辅助谐振支路与变压器交换位置,使辅助支路与超前臂相连,不仅抑制了次级寄生振荡和电压过冲,使整流管和箝位二极管工作在软开关条件下,而且减小了箝位二极管上电流有效值,减小了次级占空比丢失和初级通态损耗。分析了改进后变换器的工作原理,并对改进前后的变换器进行了比较。实验结果验证了电路的正确性。

关键词：变换器谐振/零电压开关箝位二极管辅助谐振换流网络

Photoperiod Mediates the Effects of Temperature and Light Intensity on the Proliferation of Ulva prolifera

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Journal of Ocean University of China 2024年第1期23卷 255-263页

作者： JIANG Jianan YU Yanyan CHEN Yili LI Yahe xu Nianjun Key Laboratory of Marine Biotechnology of Zhejiang Province School of Marine SciencesNingbo UniversityNingbo 315211China

In order to study the complex effects of photoperiod,temperature,and light intensity on the spore maturation and release number of Ulva prolifera,we cultured thalli segment(2–3 mm)under three different photoperiods(L:D=12:12,14:10 and 10:14),temperature(15℃(LT),25℃(MT)and 30℃(HT))and light intensity(100,200 and 400μmol m^(−2)s^(−1),noted as LL,ML and HL,respectively)*** the maturation time,spore release number and chlorophyll fluorescence were *** results suggested that:1)The spore maturation time was accelerated by higher temperature or higher light intensity from 62 h to 36 h,and changes in day length accelerated the spore maturation to a certain extent as compared with 12:12 light/dark cycle;2)Higher light intensity significantly decreased the chlorophyll fluorescence(Fv′/Fm′,NPQ,rETRmax andα)of the mature reproductive segment under 30℃with 12:12 light/dark *** when in the other photoperiods(10:14 and 14:10 conditions),the inhibitory effects of high light intensity were alleviated significantly;3)The optimum condition for the spore maturation and release was 12:12 light/dark cycle,25℃,400μmol m^(−2)s^(−1),with both shorter and longer photoperiod reducing the spore release number;4)Higher light intensity significantly increased the spore release number under 25℃,but these effects were alleviated by 30℃*** study is the first attempt to elucidate the coincidence effects of photoperiod,temperature and light intensity on the reproduction of Ulva,which would help to reveal the mechanism of the rapid proliferation of green tide.

关键词： light intensity maturation photoperiod reproduction temperature Ulva prolifera

Plasma-etching on monolithic MOFs-based MIM filter boosted chemical sensing

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Nano Research 2024年第4期17卷 2800-2807页

作者： Jianxi Liu Li Feng Zhihuan Li Yang Wu Feng Zhou Yadong xu Research&Development Institute Northwestern Polytechnical University in ShenzhenShenzhen 518057China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Shandong Laboratory of Advanced Materials and Green Manufacturing at YantaiYantai 264006China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Metal-insulator-metal(MIM)cavity as a lithography-free structure to control light transmission and reflection has great potential in the field of optical ***,the dense top metal layer of the MIM prohibits any external medium from entering the dielectric insulation layer,which limits the application of the cavity in the sensing ***,we demonstrate a series of monolithic metal-organic frameworks(MOFs)based MIM cavities,which are treated by plasma etching to provide channels for chemical diffusion and to advance *** modulate the bandwidth of the MIM filters by controlling the MOF thickness as insulator *** plasma-etching is applied to build channels on the top metal layer without altering their saturation and brightness for chemical sensing *** etching time regulates the number and size of channels on the top metal *** behavior is demonstrated on the plasma-etched MOFs-based MIM cavity when external chemicals diffuse in the *** addition,we generate patterned structure of the MOFs-based MIM cavity via plasma-mask method,which can transfer to different substrates and produce a controllable structure color change for chemical *** MIM cavity may promote the advancement and applications of structural color in security imaging,color display,information anticounterfeiting,and color printing.

关键词： metal-organic frameworks(MOFs) spin-coating metal-insulator-metal filter patterns sensing

Analytical solutions of turbulent boundary layer beneath forward-leaning waves

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 695-710页

作者： Yiqin XIE Jifu ZHOU xu WANG Jinlong DUAN Yongjun LU Shouqian LI Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210024China

As a typical nonlinear wave,forward-leaning waves can be frequently encountered in the near-shore areas,which can impact coastal sediment transport ***,it is of significance to describe the characteristics of the boundary layer beneath forward-leaning waves accurately,especially for the turbulent boundary *** this work,the linearized turbulent boundary layer model with a linear turbulent viscosity coefficient is applied,and the novel expression of the near-bed orbital velocity that has been worked out by the authors for forward-leaning waves of arbitrary forward-leaning degrees is further used to specify the free stream boundary condition of the bottom boundary ***,a variable transformation is found so as to make the equation of the turbulent boundary layer model be solved analytically through a modified Bessel ***,an explicit analytical solution of the turbulent boundary layer beneath forward-leaning waves is derived by means of variable separation and variable *** analytical solutions of the velocity profile and bottom shear stress of the turbulent boundary layer beneath forward-leaning waves are verified by comparing the present analytical results with typical experimental data available in the previous literature.

关键词： forward-leaning wave turbulent boundary layer velocity profile bottom shear stress

铁磁体/有机体/铁磁体三明治结构的隧穿磁电阻

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四川师范大学学报（自然科学版） 2009年第4期32卷 482-485页

作者：陈尚荣徐明刘杰四川师范大学物理与电子工程学院.固体物理研究所四川成都610066

对铁磁体/有机体/铁磁体三明治结构的隧穿磁电阻进行了研究.考虑有机层对自旋的过滤作用,用Slonczewsk i自由电子理论模型计算了不同的隧穿势垒下在高自旋过滤因子和低自旋过滤因子两种情况隧穿磁电阻随有机层厚度的变化.计算结果供设... 详细信息

对铁磁体/有机体/铁磁体三明治结构的隧穿磁电阻进行了研究.考虑有机层对自旋的过滤作用,用Slonczewsk i自由电子理论模型计算了不同的隧穿势垒下在高自旋过滤因子和低自旋过滤因子两种情况隧穿磁电阻随有机层厚度的变化.计算结果供设计新的有机自旋电子器件参考.

关键词：磁性隧道结铁磁层有机体隧穿磁电阻

福州地区尖锐湿疣患者HPV检测及基因分型分析

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中国皮肤性病学杂志 2014年第5期28卷 488-489,508页

作者：张弘徐明赵敬军福州市皮肤病防治院福建福州350012 同济大学附属同济医院皮肤科上海200065

目的探讨福州地区人乳头瘤病毒（HPV）感染的分子流行病学特点，从而为尖锐湿疣（CA）患者的监测提供一定的临床依据。方法采用HybriMax技术对福州地区600例CA患者的皮损组织进行HPV检测及分型。结果585例患者呈HPV感染阳性，共发现20种... 详细信息

目的探讨福州地区人乳头瘤病毒（HPV）感染的分子流行病学特点，从而为尖锐湿疣（CA）患者的监测提供一定的临床依据。方法采用HybriMax技术对福州地区600例CA患者的皮损组织进行HPV检测及分型。结果585例患者呈HPV感染阳性，共发现20种HPV亚型。HPV单一型感染372例，占63．59％。213例存在2～6种亚型的混合感染，多重型别感染率达到36．41％（213／585）。结论福州地区尖锐湿疣患者以低危型HPV6／11为主，高危型HPV感染卒高并多以混合感染形式存在。

关键词：人乳头瘤病毒尖锐湿疣基因芯片

Persistent radical anion of perylene dianhydride:an emerging metal-free photocatalyst for near-infrared photocontrolled RAFT polymerization

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Science China Chemistry 2024年第2期67卷 677-686页

作者： Haitao Zhao Guoqing Bian Xiang xu Weiwei He Lifen Zhang Zhenping Cheng State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China

Developing a new type of photocatalyst(PC) and catalytic mechanism for near-infrared(NIR) photocontrolled reversibledeactivation radical polymerization(RDRP) system is charming but ***,a novel PC of the persistent radical anion(PRA)(possessing the properties of both radical and anion) was developed for NIR photocontrolled reversible additionfragmentation chain transfer(RAFT) polymerization,enabling successful polymerization while gaining a deep insight into the mechanism of photo-induced electron transfer RAFT(PET-RAFT) *** from the conventional and wellaccepted reductive quenching(RQ) pathway,in which the radical anion intermediates of PCs(PCs^(·-)) must be generated in an excited state(ES),here,the PRA(3,4,9,10-perylenetetracarboxylic dianhydride radical anion(PTCDA^(·-))) could generate conveniently in situ in the ground state(GS) and subsequently serve as highly efficient PC in the NIR region(740–850 nm).The successful implementation of this strategy elucidates the peculiar role played by light and the real way of electron transfer *** fact,the transfer of a single electron from PRA to chain transfer agent(CTA) and cleavage of the C–S bonds is a process from ES to GS,rather than always from GS(PCs^(·-)) to GS(CTA) in the RQ pathway as is well known to *** addition,the excellent spatial-temporal control and powerful penetration ability of the NIR light were also confirmed by this PRAcatalyzed polymerization system.

关键词： photocatalyst persistent radical anion(PRA) near-infrared(NIR)light reversible-deactivation radical polymerization(RDRP) photo-induced electron transfer RAFT(PET-RAFT)polymerization