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Collapse Simulation and Response Assessment of a Large Cooling Tower Subjected to Strong Earthquake Ground Motions

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 691-715页

作者： Tiancan huang Hao Zhou Hamid Beiraghi Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou510405China Department of Civil Engineering South China University of TechnologyGuangzhou510641China Department of Civil Engineering Mahdishahr BranchIslamic Azad UniversityMahdi Shahr***Iran

Large cooling towers in thermal power plants and nuclear power plants are likely to suffer from strong earthquakes during service *** resulting destructions of the cooling towers would endanger the power plants and threaten the security of the related *** is important to use effective means to evaluate the safety status of the cooling towers and guide further precautions as well as retrofitting *** paper is therefore focused on an elaborate numerical investigation to the earthquake-induced collapses of a large cooling tower structure.A complete numerical work for simulation of material failure,component fracture,structural buckling and system collapse is presented by integrating the stochastic damage constitutive model of concrete,refined structural element models,and some other key *** results indicate that the damage behavior and collapse mode of the cooling tower are affected notably by the randomness specification of ground *** collapse mechanisms of the cooling tower are studied from the energy absorption and dissipation points of *** effective energy-based criterion is introduced to identify the collapse of the cooling tower under ground motion *** distinct collapse modes are observed,the collapse criterion can predict well the damage and failure of the cooling *** proposed methodology is vital to better understanding the disastrous mechanisms and potential failure paths in optimal design of the cooling towers to ensure safety.

关键词： Cooling tower concrete damage mechanics collapse criterion responses

Dynamic measurements of serum inhibin B and estradiol: a predictive evaluation of ovarian response to gonadotrophin stimulation in the early stage of IVF treatment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第1期10卷 35-45页

作者： Ming-fang MIAO He-feng huang Department of Reproductive Endocrinology Women's Hospital School of Medicine Zhejiang University Hangzhou 310006 China

Objective： We dynamically measured serum inhibin B and estradiol in the early stage of hormonal stimulation to predict the ovarian response in in vitro fertilization （IVF） treatment. Methods： A total of 57 patients （〈40 years of age） who underwent the first cycle of long protocol IVF or introcytoplasmic sperm injection （ICSI） treatment were included. Serum inhibin B, estradiol, follicle stimulating hormone （FSH） and luteinizing hormone （LH） levels were measured four times：（1） on Day 3 of the menstrual cycle （basal）; （2） on the day before the first administration ofgonadotrophin （Gn）（Day 0）; （3） on Day 1 of Gn therapy; and （4） on Day 5 of Gn therapy. Comparisons of these measurements with ovarian responses and pregnancy outcomes were made and analyzed statistically. Results：（1） On Day 1 and Day 5 of recombinant FSH （rFSH） stimulation, ovarian response, i.e., numbers of follicles, oocytes, fertilized oocytes, and embryos, had a positive correlation （rs=0.46-0.61, P 0.000） with raised inhibin B and estradiol concentrations, but a negative correlation （rs=-0.67--0.38, P=0.000 or P〈0.01） with total rFSH dose and total days ofrFSH stimulation. （2） No significant variation （P〉0.05） between the pregnant and non-pregnant groups on the basis of mean age or on all hormone concentrations at four times of the IVF cycle was observed. However, all the seven patients aged 〉35 years did not reach pregnancy. Conclusions：（1） Serum inhibin B and estradiol concentrations obtained shortly after Gn therapy may offer an accurate and early prediction of ovarian response; （2） Low levels of serum inhibin B and estradiol obtained shortly after Gn stimulation indicate the need for a longer period of Gn treatment and a higher daily dosage; （3） No obvious pregnancy difference among patients of age 〈35 years was found; however, IVF pregnancy outcome is significantly lower in women of age 〉35 years.

关键词： Inhibin B Estradiol Ovarian response In vitro fertilization (IVF) Pregnancy

Isometries and Additive Mapping on the Unit Spheres of Normed Spaces

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Acta Mathematica Sinica,English Series 2017年第10期33卷 1431-1442页

作者： Rui Dong WANG Xu Jian huang Science of College Tianjin University of Technology Tianjin 300384 P. R. China

In this paper, we investigate isometric extension problem in general normed space. We prove that an isometry between spheres can be extended to a linear isometry between the spaces if and only if the natural positive homogeneous extension is additive on spheres. Moreover, this conclusion still holds provided that the additivity holds on a restricted domain of spheres.

关键词： Isometric extension additive mapping unit sphere angle

Tabu search algorithm combined with global perturbation for packing arbitrary sized circles into a circular container

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Science China(Information Sciences) 2013年第9期56卷 140-153页

作者： huang WenQi FU ZhangHua XU RuChu School of Computer Science and Technology Huazhong University of Science and Technology

The arbitrary sized circle packing problem (ACP) is concerned about how to pack a number of arbitrary sized circles into a smallest possible circular container without overlapping. As a classical NP-hard problem, ACP is theoretically important and is often encountered in practical applications. Based on the already existing Quasi-physical method, this paper proposes a hybrid algorithm named GP-TS which combines tabu search with global perturbation to solve the two-dimensional ACP. The Quasi-physical method is a continuous optimization method which is used to obtain a local optimal configuration from any initial configuration. The tabu search procedure iteratively updates the incumbent configuration with its best neighboring configuration according to some forbidden rule and aspiration criterion. If the configuration obtained by the tabu search procedure does not satisfy the constraints, the global perturbation operator is subsequently applied in order that the search jumps out of the current local optimum without destroying the incumbent configuration too much. After that, the tabu search procedure is launched again. GP-TS is performed by repeating this process until the stop criterion is met. Computational experiments based on 3 sets of representative instances show that GP-TS can improve many best known results within reasonable time.

关键词： packing tabu search global perturbation quasi-physical quasi-human

清江流域生态安全评估指标体系及治理措施研究

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人民长江 2016年第18期47卷 5-10页

作者：王守文黄刚三峡大学法学与公共管理学院湖北宜昌443002 华中科技大学经济学院湖北武汉430074 三峡大学电气与新能源学院湖北宜昌443002

流域作为一种特殊的自然资源区域类型,为区域经济社会的发展提供着强大的动力和支撑。然而随着人口的日益增长和人类活动的加剧,人地矛盾日趋严重,流域大规模经济开发对其生态安全造成了前所未有的威胁,河流污染严重、水土流失加剧、生... 详细信息

流域作为一种特殊的自然资源区域类型,为区域经济社会的发展提供着强大的动力和支撑。然而随着人口的日益增长和人类活动的加剧,人地矛盾日趋严重,流域大规模经济开发对其生态安全造成了前所未有的威胁,河流污染严重、水土流失加剧、生态修复能力下降等问题日益突出。以湖北省清江流域为例,针对清江流域生态安全问题展开了原因分析,并通过层次分析法建立了指标评价体系;在客观分析评价结果的基础上,提出了切实可行的治理措施体系,即完善流域生态安全法律保护体系、提高公众生态安全意识、创新流域生态安全管理相关制度以及整合其他社会资源与力量,以此来探索流域综合开发与治理的模式,促进区域协调可持续发展。

关键词：生态安全安全评估治理措施指标体系清江流域

抗癫癎药物对正常幼年大鼠脑内多药耐药基因MDR1表达的影响

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中华儿科杂志 2007年第4期45卷 293-294页

作者：张婕黄绍平李丹西安市儿童医院儿童保健科 710002 西安交通大学第二医院儿科 710004

近年来，国内外对于难治性癫痫发病机制的研究已经证实，多药耐药基因（MDR）在癫痫病灶内存在异常高表达现象，这种高表达可能通过一种非特异性的机制将一部分结构与其底物类似的化合物，包括大部分抗癫痫药（AEDs），从其作用部位排... 详细信息

近年来，国内外对于难治性癫痫发病机制的研究已经证实，多药耐药基因（MDR）在癫痫病灶内存在异常高表达现象，这种高表达可能通过一种非特异性的机制将一部分结构与其底物类似的化合物，包括大部分抗癫痫药（AEDs），从其作用部位排出，造成局部药物的有效浓度降低，使癫痫发作难以控制。导致多药耐药基因1（MDR1）表达增加的原因还不清楚，可能是多方面的，绝大多数作者认为癫痫长期反复发作可以诱导MDR1的高表达，但是不同的学者对于抗癫痫药物是否会诱导MDR1表达增高还存在争议，尽管体外培养细胞显示AEDs对MDR1存在诱导作用，但是在活体动物的研究这一点却没有得到证实。儿童是癫痫的高发人群，未成熟脑既有与成熟脑相近的解剖生理结构，又有与成熟脑不同的发育中脑特征表现。目前国外的文献均限于成年动物的研究，2004年12月至2005年12月，我们以MDR1基因表达产物P糖蛋白（PGP）为观察指标，观察了AEDs对未成熟脑MDR1的表达是否存在诱导作用。报告如下。

关键词：多药耐药基因MDR1 抗癫痫药物脑内幼年大鼠未成熟脑基因表达产物诱导作用 AEDs

Geo-engineering Lessons Learned from the 2008 Wenchuan Earthquake in Sichuan and Their Significance to Reconstruction

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Journal of Mountain Science 2011年第2期8卷 176-189页

作者： huang Runqiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 Sichuan China

The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in planning post-disaster recovery and rebuilding. This paper presents recommendations for coping with large-scale geohazards and disasters. It is essential to establish a national emergency management system for huge scale catastrophe and earthquake precursor identification. Town construction must be kept away from active faults, especially to improve town safety in areas with high risk of seismic and geological hazards, and it is important to improve geohazard investigation and remediation for mountain areas that have become loosened by earthquake activity. Geological factors must be better understood to reduce direct and secondary risks and effects of earthquakes. Site selections for public relocation require clear and informed analysis of geological and social risk reduction, so that relocation, infrastructure reconstruction, and commemorative relic-sites can be protected.

关键词： Wenchuan Earthquake Geohazard Reconstruction

A topographic parameter inversion method based on laser altimetry

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Science China(Technological Sciences) 2012年第5期55卷 1273-1280页

作者： huang ChunMing ZHANG shaoDong CHEN Xi School of Electronic Information Wuhan UniversityWuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan 430079China State Observatory for Atmospheric Remote Sensing Wuhan 430079China

A topographic parameter inversion method based on laser altimetry is developed in this paper, which can be used to deduce the surface vertical profile and retrieve the topographic parameters within the laser footprints by analyzing and simulating return waveforms. This method comprises three steps. The first step is to build the numerical models for the whole measuring procedure of laser altimetry, construct digital elevation models for surfaces with different topographic parameters, and calculate return waveforms. The second step is to analyze the simulated return waveforms to obtain their characteristics parameters, summarize the effects of the topographic parameter variations on the characteristic parameters of simulated return waveforms, and analyze the observed return waveforms of laser altimeters to acquire their characteristic parameters at the same time. The last step is to match the characteristic parameters of the simulated and observed return waveforms, and deduce the topographic parameters within the laser footprint. This method can be used to retrieve the topographic parameters within the laser footprint from the observed return waveforms of spaceborne laser altimeters and to get knowledge about the surface altitude distribution within the laser footprint other than only getting the height of the surface encountered firstly by the laser beam, which extends laser altimeters' function and makes them more like radars.

关键词： Laser altimetry return waveform simulation Gaussian fitting topographic parameter inversion

MAPK signaling in inflammation-associated cancer development

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Protein & Cell 2010年第3期1卷 218-226页

作者： Pengyu huang Jiahuai Han Lijian Hui Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering School of Life SciencesXiamen UniversityXiamen 361005China

Mitogen-activated protein(MAP)kinases comprise a family of protein-serine/threonine kinases,which are highly conserved in protein structures from unicellular eukaryotic organisms to multicellular organisms,including *** kinases,including ERKs,JNKs and p38s,are regulated by a phosphorelay cascade,with a prototype of three protein kinases that sequentially phosphorylate one *** transduce extracellular signals into a variety of cellular processes,such as cell proliferation,survival,death,and *** with their essential cellular functions,MAPKs have been shown to play critical roles in embryonic development,adult tissue homeostasis and various *** this review,we discuss recent findings that reveal the profound impact of these pathways on chronic inflammation and,particularly,inflammation-associated cancer development.

关键词： inflammation cancer homeostasis