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基于结构方程模型的绿色铁路建造能力形成机理研究

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铁道科学与工程学报 2024年第3期21卷 1213-1221页

作者：王青娥潘阿敏郭珍旭潘丽鹦高速铁路建造技术国家工程研究中心湖南长沙410075 中南大学土木工程学院湖南长沙410075 中国中铁股份有限公司北京100039

在“碳达峰碳中和”双碳目标驱动下,铁路的绿色转型势在必行,然而目前铁路工程企业绿色铁路建造能力尚显不足,究其原因是由于绿色铁路建造能力建设目标不明确、依据不充分。首先,通过文献分析归纳出绿色铁路建造能力的4个构成维度,筛选... 详细信息

在“碳达峰碳中和”双碳目标驱动下,铁路的绿色转型势在必行,然而目前铁路工程企业绿色铁路建造能力尚显不足,究其原因是由于绿色铁路建造能力建设目标不明确、依据不充分。首先,通过文献分析归纳出绿色铁路建造能力的4个构成维度,筛选识别出5类影响因素和23个影响因素指标。其次,根据绿色铁路建造领域相关研究成果提出影响因素作用的研究假设,建立结构方程概念模型。最后,通过调查问卷进行数据收集,进行理论模型的拟合和检验,再基于拟合结果分析揭示各影响因素对企业绿色铁路建造能力的作用效应。研究结果表明:企业技术发展及人才建设水平、行业发展水平、企业内部绿色发展水平、企业综合管理水平和政府推力对绿色铁路建造能力均有显著正向影响,且影响效应依次递减;政府推力和行业发展水平仅对绿色铁路建造能力产生间接影响,企业内部绿色发展水平、企业综合管理水平和企业技术发展及人才建设水平仅起直接作用。研究揭示了绿色铁路建造能力的形成机理,为提高企业绿色铁路建造能力提供理论依据,有助于提高铁路工程企业对绿色铁路建造能力的认知水平,帮助其快速实现绿色转型。

关键词：绿色铁路绿色建造能力影响因素结构方程模型形成机理

Geometrically Nonlinear Bending Analysis of Metal-Ceramic Composite Beams under Thermomechanical Loading

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 701-713页

作者： TORABIZADEH Mohammad amin Department of Industrial Design Engineering University of Applied Science and Technology

A new method is developed to derive equilibrium equations of Metal-Ceramic beams based on first order shear deformation plate theory which is named first order shear deformation beam theory2(FSDBT2). Equilibrium equations obtained from conventional method (FSDBT1) is compared with FSDBT2 and the case of cylindrical bending of Metal-Ceramic composite plates for non-linear thermomechanical deformations and various loadings and boundary conditions. These equations are solved by using three different methods (analytical, perturbation technique and finite element solution). The through-thickness variation of the volume fraction of the ceramic phase in a Metal-Ceramic beam is assumed to be given by a power-law type function. The non-linear strain-displacement relations in the von-Kármán sense are used to study the effect of geometric non-linearity. Also, four other representative averaging estimation methods, the linear rule, Mori-Tanaka, Self-Consistent and Wakashima-Tsukamoto schemes, by comparing with the power-law type function are also investigated. Temperature distribution through the thickness of the beams in thermal loadings is obtained by solving the one-dimensional heat transfer equation. Finally it is concluded that for Metal-Ceramic composites, these two theories result in identical static responses. Also the displacement field and equilibrium equations in the case of cylindrical bending of Metal-Ceramic plates are the same as those supposed in FSDBT2.

关键词： thermomechanical loading functionally graded beams monlinear analysis analytical solution

Crack detection of the cantilever beam using new triple hybrid algorithms based on Particle Swarm Optimization

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Frontiers of Structural and Civil Engineering 2022年第9期16卷 1127-1140页

作者： amin GHANNADIASL Saeedeh GHAEMIFARD Department of Civil Engineering University of Mohaghegh ArdabiliArdabil 56199-11367Iran

The presence of cracks in a concrete structure reduces its performance and increases in the size of cracks result in the failure of the ***,the accurate determination of crack characteristics,such as location and depth,is one of the key engineering issues for assessment of the reliability of *** paper deals with the inverse analysis of the crack detection problems using triple hybrid algorithms based on Particle Swarm Optimization(PSO);these hybrids are Particle Swarm Optimization-Genetic Algorithm-Firefly Algorithm(PSO-GA-FA),Particle Swarm Optimization-Grey Wolf Optimization-Firefly Algorithm(PSO-GWO-FA),and Particle Swarm Optimization-Genetic Algorithm-Grey Wolf Optimization(PSO-GA-GWO).A strong correlation exists between the changes in the natural frequency of a concrete beam and the crack ***,the location and depth of a crack in a beam can be predicted by measuring its natural ***,the measured natural frequency can be used as the input parameter of the *** this paper,this is applied to identify crack location and depth in a cantilever beam using the new hybrid *** results show that among the proposed triple hybrid algorithms,the PSO-GA-FA and PSO-GWO-FA algorithms are much more effective than PSO-GA-GWO algorithm for the crack detection.

关键词： crack cantilever beam triple hybrid algorithms Particle Swarm Optimization

Effect of the spectral shape of ground motion records on the collapse fragility assessment of degrading SDOF systems

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Earthquake Engineering and Engineering Vibration 2021年第4期20卷 925-941页

作者： amin Norouzi Mehdi Poursha Department of Civil Engineering Sahand University of TechnologyTabriz 51335-1996Iran Earthquake Engineering Research Center Sahand University of TechnologyTabriz 51335-1996Iran

The main purpose of this paper is to study the collapse capacity of single degree of freedom(SDOF)systems and to produce fragility curves as well as collapse capacity spectra while considering a broad range of structural parameters,including system degradation,the P-Δeffect,ductility capacity and the post-capping stiffness *** modified Ibarra-Krawinkler deterioration model was used to consider hysteretic behavior.A comprehensive study was conducted to extract the collapse capacity spectrum of SDOF systems with a wide range of periods,varying from 0.05 to 4 s,to cover short,intermediate and long *** dynamic analysis(IDA)was performed for SDOF systems to identify the condition in which the collapse capacity of the system is *** IDAs were performed using different sets of seismic ground *** ground motion records were categorized into different sets based on three spectral shape parameters,including the epsilon,SaRatio and N_(p).The collapse fragility curves of SDOF systems with different periods were extracted to illustrate the collapse capacity at different probability *** results show that structural degradation and ductility as well as the spectral shape parameters significantly affect the collapse capacity of SDOF *** the other hand,the post-capping stiffness ratio and small levels of the P-Δeffect do not remarkably change collapse ***,the collapse capacity of SDOF systems is more sensitive to the records categorized based on SaRatio and N_(p)than those classified based on epsilon.

关键词： collapse capacity fragility analysis degrading SDOF system IDA curve Epsilon,N_(p) SaRatio P-Δeffect

“西迁精神”指引下医务人员获得感的提升路径分析

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中国医学伦理学 2024年第8期37卷 974-979页

作者：屈阿敏杨敏吴楠杨娟西安交通大学第一附属医院门诊部陕西西安710061 西安交通大学第一附属医院呼吸科陕西西安710061

在分析西迁精神内涵、精髓及在医疗领域独特表现和价值的基础上,通过强化医务人员的职业认同感和荣誉感、优化医务人员的工作环境和待遇、加强医务人员的专业素养和技能培训、加强医务人员的心理健康和关怀等具体措施,以期增强医务人员... 详细信息

在分析西迁精神内涵、精髓及在医疗领域独特表现和价值的基础上,通过强化医务人员的职业认同感和荣誉感、优化医务人员的工作环境和待遇、加强医务人员的专业素养和技能培训、加强医务人员的心理健康和关怀等具体措施,以期增强医务人员获得感,更好履行自己的职责,为提高人民群众健康水平,构建和谐医患关系贡献自己的力量。

关键词：医务人员西迁精神获得感医患关系社会环境

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THREE NONTRIVIAL SOLUTIONS FOR A NONLINEAR ANISOTROPIC NONLOCAL EQUATION

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Acta Mathematica Scientia 2018年第4期38卷 1296-1310页

作者： amin ESFAHANI School of Mathematics and Computer Science Damghan University

In this article, we establish the existence of a sign-changing solution and two sign- constant solutions for nonlinear nonlocal problem involving the BO-ZK operator on bounded domain. Our main tool is constrained mini... 详细信息

关键词： sign-constant and nodal solutions BO-ZK operator variational method

Topical negative pressure in managing severe peritonitis: A positive contribution?

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World Journal of Gastroenterology 2009年第27期15卷 3394-3397页

作者： amin Ibrahim amin Irshad A Shaikh Consultant surgeon Queen Margaret hospitalDunfermline Scotland KY12 0SU United Kingdom Specialist Registrar Royal Infirmary of EdinburghLittle France Edinburgh Scotland EH16 4SAUnited Kingdom

AIM： To assess the use of topical negative pressure （TNP） in the management of severe peritonitis. METHODS： This is a four-year prospective analysis from January 2005 to December 2008 of 20 patients requiring TNP following laparotomy for severe peritonitis. RESULTS： There were 11 males with an average age of （59.3 ± 3.95） years. Nine had a perforated viscus, five had anastomotic leaks, three had iatrogenic bowel injury, and a further three had severe pelvic inflammatory disease. TNP and the VAC Abdominal Dressing System were initially used. These were changed every two to three days. Abdominal closure was achieved in 15/20 patients within 4.53 ± 1.64 d. One patient required relaparotomy due to residual sepsis. Two patients with severe faecal peritonitis due to perforated diverticular disease received primary anastomosis at second look laparotomy, as sepsis and their general condition improved. In the remaining 5/20 cases, the abdomen was lee open due to bowel oedema and or abdominal wall oedema. Dressing was switched to TNP and VAC GranuFoam . Three of the five patients returned a few months later for abdominal wall reconstruction and restoration of intestinal continuity. Two patients developed intestinal fistulae. All 20 patients survived.CONCLUSION： The use of TNP is safe. Further studies are needed to assess its value in managing these difficult cases.

关键词： Severe peritonitis Open abdomen Topicalnegative pressure VAC Abdominal Dressing System VAC GranuFoam

Insecticidal efficacy of three vegetable oils as post-harvest grain protectants of stored wheat against Rhyzopertha dominica （F.）（Coleoptera： Bostrychidae）

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Insect Science 2007年第2期14卷 145-150页

作者： amin NIKPAY Department of Entomology College of Agriculture Urmia University Urmia Iran

The lesser grain borer, Rhyzopertha dominica is a major insect pests of stored grain in the tropics. Vegetable oils （chamomile, sweet almond and coconut） at 2.5, 3.5, 5.0, 7.0 and 10.0 mL/kg were tested against Rhyzopertha dominica （F.） in wheat grain. All bioassays were conductr, d at 30℃ and 65% ＋ 2% RH. Treatments with vegetable oils at high dose （10.0 mL/kg） achieved over 95% control within 24 h of exposure to freshly treated grain, There was little difference between the three oils in their effect. Persistence of oils in grains was tested at short-term storage intervals （48, 72 and 96 h） and intermediate-term intervals （10, 20 and 30 days） after treatments. The activity of all products decreased with storage period. Seed viability was reduced by the high dose rate （10.0 mL/kg） of oil treatments. The potential use of vegetable oils as supplementary or alternative grain protectants against insect damage in traditional grain storage in developing countries is discussed.

关键词： Rhyzopertha dominica seed viability traditional grain storage tropics,vegetable oils

Traveling Wave Solutions for Generalized Bretherton Equation

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Communications in Theoretical Physics 2011年第3期55卷 381-386页

作者： amin Esfahani School of Mathematics and Computer Science Damghan University Damghan 36716-41167 Iran

This paper studies the Generalized Bretherton equation using trigonometric function method including the sech-function method, the sine-cosine function method, and the tanh-function method, and He＇s semi-inverse method （He＇s variational method）. Various traveling wave solutions are obtained, revealing an intrinsic relationship among the amplitude, frequency, and wave speed.

关键词： Bretherton equation traveling wave trigonometric function method variational method