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Crack status analysis for concrete dams based on measured entropy

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Science China(Technological Sciences) 2016年第5期59卷 777-782页

作者： WU Bang Bin WU Zhong Ru CHEN Bo SU Huai Zhi BAO Teng Fei wang shao wei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

The integrity and safety of concrete darns are seriously affected by the existing cracks in dam bodies, and some serious cracks may cause dam failure or disaster. The propagation of cracks in concrete dams is accompanied by changes in energy distribution, which can be represented by changes in the structure＇s system entropy. Therefore, the entropy theory can be used in analyzing the behavior of dam cracks. Due to the randomness and locality of crack propagation, it is difficult to predict the loca- tion of cracks by traditional monitoring methods. To solve this problem, the influence of spatial positions of monitoring points on inspection zones is represented by a weight index, and the weight index is determined by the distance measure method proposed in this paper. Through the weighted linear fusion method, the entropy of multiple monitoring points is obtained for analyzing the behavior of dam cracks in the selected zones. Meanwhile, the catastrophe theory is used as the variation criterion of an entropy sequence in order to predict the instability time of dam cracks. Case studies are put forward on a high arch darn, and the fusion entropy is calculated according to the monitoring data from strain gauges. Results show that the proposed method can effectively predict the occurrence time and location of dam cracks regardless of the layout of monitoring instruments, and it is a new way to analyze the occurrence and propagation of dam cracks.

关键词： energy measured data entropy changes multiple monitoring points fusion concrete dam

An efficient synthesis of 3-(guaiazulene-1-yl)succinimides by addition of guaiazulene to maleimides

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Chinese Chemical Letters 2011年第7期22卷 789-792页

作者： Dao Lin wang shao Fei Li wei Li Yuan Feng Li Li Nan Lin Key Laboratory of Synthesis & Application of Functional Compound College of Chemistry & Chemical Engineering Bohai University Jinzhou 121001 China

A facile, efficient synthesis of 3-（guaiazulen-l-yl）succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.

关键词： Guaiazulene Succinimidcs Michael-type addition p-Toluenesulfonic acid

Ethnic Differences in Preterm Birth Risks for Pregnant Women with Thyroid Dysfunction or Autoimmunity:A Meta-analysis

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Biomedical and Environmental Sciences 2016年第10期29卷 724-733页

作者： LI Min wang shao wei WU Feng Li SHI Jin YU Pu Lin PENG Xiu Ling SUN Liang Department of Gynecology and Obstetrics Beijing HospitalNational Center of Gerontology Institute of Geriatrics Beijing HospitalNational Center of Gerontology Department of Gynecology and Obstetrics Morin Dawa Daur Autonomous Banner Hospital

Objective Abnormal maternal thyroid function is associated with preterm ***,this association stays dubious in relevant individual studies for ethnic difference reasons and lack of direct supporting *** study aimed to evaluate the relationship between preterm birth and thyroid dysfunction or autoimmunity based on ethnic *** Relevant studies were identified through searches of MEDLINE,Excerpta Medica,Wan Fang,China Biological Medicine disc,and China National Knowledge Infrastructure from inception to June 15,*** articles in which an incidence or prevalence of thyroid dysfunction or autoimmunity before second trimester of pregnancy could be extracted were *** Thirty-two unique studies were included for the final *** involved were divided into two groups：Group 1（G1） and Group 2（G2） comprising of Asian and Caucasian populations,*** thyroid antibodies were associated with the occurrence of preterm birth in both G1 [odds ratio（OR）：3.62,95% confidence interval（CI）：2.83-4.65] and G2（OR：1.35,95% CI：1.17-1.56）;hypothyroidism,only in G2（OR：1.20,CI：1.09-1.33）;and subclinical hypothyroidism or hypothyroxinemia,in neither *** Thyroid autoimmunity may be a more favorable factor leading to preterm birth among pregnant women of different ethnicities,compared with thyroid dysfunction.

关键词： Thyroid Hypothyroidism Autoimmunity Preterm birth Ethnicity

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《诗经》山水阻隔诗的文化意蕴

安徽师范大学学报（社会科学版） 2011年第6期39卷 672-677页

作者：王绍卫宿州学院文学院安徽宿州234000

从山水阻隔诗的形成、在《诗经》中的表现以及作为补偿机制出现的登高、舟船意象等方面探讨《诗经》山水阻隔诗深刻的文化意蕴。

关键词：《诗经》山水阻隔突破文化意蕴

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

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水位变化下可压缩土层的黏弹性耦合变形分析

岩土力学 2020年第3期41卷 1065-1073页

作者：徐进王少伟杨伟涛烟台大学土木工程学院山东烟台264005

地下水开采等人类工程活动会引起地下水位变化,从而导致地面沉降问题。地面沉降具有土层变形长期发展的特点,土体的蠕变性是导致这一现象的重要原因之一。为此,针对基于Biot理论的地面沉降耦合模型,利用半解析数值原理和黏弹性流变理论... 详细信息

地下水开采等人类工程活动会引起地下水位变化,从而导致地面沉降问题。地面沉降具有土层变形长期发展的特点,土体的蠕变性是导致这一现象的重要原因之一。为此,针对基于Biot理论的地面沉降耦合模型,利用半解析数值原理和黏弹性流变理论,推导了可压缩土层黏弹性耦合变形的求解格式,该计算方法无需数值积分,且具有很好的解耦并行性。在此基础上,编制了FORTRAN计算程序,通过与已有解答的对比验证,说明了方法及程序的合理性,计算结果可以正确反映土体黏滞性所导致的变形滞后效应。通过数值算例,进一步探讨了渗透性、孔隙流体可压缩性和土体黏滞性等因素对土层长期变形的影响规律。

关键词：地下水位变化地面沉降半解析数值法黏弹性流变模型

Theoretical Proof of Unconditional Stability of the 3-D ADI-FDTD Method

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Journal of Electronic Science and Technology of China 2003年第1期1卷 1-5页

作者： wang Yingjun wang Bingzhong shao wei (School of Physical Electronics,UESTC Chengdu 610054 China) School of Physical Electronics UESTC Chengdu 610054 China

In order to eliminate Courant-Friedrich-Levy(CFL) condition restraint and improvecomputational efficiency,a new finite-difference time-domain(FDTD)method based on the alternating-direction implicit(ADI) technique is introduced *** this paper,a theoretical proof of the stabilityof the three-dimensional(3-D)ADI-FDTD method is *** is shown that the 3-D ADI-FDTDmethod is unconditionally stable and free from the CFL condition restraint.

关键词： alternating-direction implicit(ADI)technique Courant-Friedrich-Levy(CFL)condition restraint finite-difference time-domain(FDTD)method stability

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最优多用户检测问题适应值曲面分析

南京大学学报（自然科学版） 2009年第4期45卷 447-454页

作者：王少尉南京大学电子科学与工程系南京210093

对于码分多址无线通信,多用户检测技术是克服多址干扰的有效手段,尽管最优多用户检测算法具有最好的检测性能,但是其计算复杂度和用户数量呈指数增长,不可能在实际系统中实现.已经证明最优多用户检测是non-deterministic potynomial(NP... 详细信息

对于码分多址无线通信,多用户检测技术是克服多址干扰的有效手段,尽管最优多用户检测算法具有最好的检测性能,但是其计算复杂度和用户数量呈指数增长,不可能在实际系统中实现.已经证明最优多用户检测是non-deterministic potynomial(NP)完备的组合优化问题,目前还不存在有效的多项式复杂度算法来求得其精确解,而启发式方法作为求解这类问题的有效方法,可以在合理的计算时间内获得高质量的解.启发式算法性能的最重要因素是相应问题的适应值曲面特性,对特定问题的属性分析能够帮助我们理解启发式搜索算法的行为和预测其性能.本文给出了适应值曲面的概念和最优多用户检测问题的组合优化模型,指出影响启发式多用户检测算法性能的几个主要属性,定义了几个重要测度以量化这些属性并且对最优多用户检测问题的适应值曲面进行了数值仿真和分析,指出了数值仿真结果对设计高效启发式算法的指导意义.

关键词：码分多址多用户检测适应值曲面组合优化启发式算法

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全地下式排水泵站的设计经验

中国给水排水 2015年第22期31卷 50-53页

作者：王绍伟沈阳市市政工程设计研究院辽宁沈阳110015

全地下式排水泵站占地面积小、绿化率高,对周围环境的不良影响小,合理的设计可以使泵站与周围环境融为一体,是城市排水基础设施建设的发展方向。全地下式泵站的设计理念是尽量保证泵站的水力布局,主体结构上采用空间分层,将原来位于地... 详细信息

全地下式排水泵站占地面积小、绿化率高,对周围环境的不良影响小,合理的设计可以使泵站与周围环境融为一体,是城市排水基础设施建设的发展方向。全地下式泵站的设计理念是尽量保证泵站的水力布局,主体结构上采用空间分层,将原来位于地上的各功能房间建于地下,地上仅保留设备吊装洞口,送、排风口,人员进出通道等。设计的关键是空间布局和设备选型。结合工程案例,提出了全地下式排水泵站的建设理念,总结了全地下式排水泵站的设计经验。

关键词：全地下式排水泵站设备除臭管理