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3-D Animation as Applied to the Solving of Coupling Relations in the 6-DOF Parallel Robot
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作者 徐雷麟 王立荣 李恩光 《Journal of Donghua University(English Edition)》 EI CAS 2002年第4期98-101,共4页
How to solve the coupling relations in a 6 - DOF parallel robot quickly and accurately within the limits of realtime control is a critical problem. In traditional analytic method, the complicated mathemtical model mus... How to solve the coupling relations in a 6 - DOF parallel robot quickly and accurately within the limits of realtime control is a critical problem. In traditional analytic method, the complicated mathemtical model must first be constructed and then solved by programming.Obviously, this method is not very practical. This paper,therefore, proposes a new way of approach with a new method using 3- D animation for the solving of coupling relations in the 6 - DOF parallel robot. This method is much simpler and its solving accuracy approaches that of the more complicated analytic method. 展开更多
关键词 parallel robot the coupling relations of movement 3 - D animation simulation technology real-time control
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Three Dimensional Coupling between Elastic and Thermal Fields in the Static Analysis of Multilayered Composite Shells 被引量:1
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作者 Salvatore Brischetto Roberto Torre Domenico Cesare 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2551-2594,共44页
This new work aims to develop a full coupled thermomechanical method including both the temperature profile and displacements as primary unknowns of the model.This generic full coupled 3D exact shell model permits the... This new work aims to develop a full coupled thermomechanical method including both the temperature profile and displacements as primary unknowns of the model.This generic full coupled 3D exact shell model permits the thermal stress investigation of laminated isotropic,composite and sandwich structures.Cylindrical and spherical panels,cylinders and plates are analyzed in orthogonal mixed curved reference coordinates.The 3D equilibrium relations and the 3D Fourier heat conduction equation for spherical shells are coupled and they trivially can be simplified in those for plates and cylindrical panels.The exponential matrix methodology is used to find the solutions of a full coupled model based on coupled differential relations with respect to the thickness coordinate.The analytical solution is based on theories of simply supported edges and harmonic relations for displacement components and sovra-temperature.The sovra-temperature magnitudes are directly applied at the outer faces through static state hypotheses.As a consequence,the sovra-temperature description is assumed to be an unknown variable of themodel and it is calculated in the sameway as the three displacements.The final systemis based on a set of coupled homogeneous differential relations of second order in the thickness coordinate.This system is reduced in a first order differential relation system by redoubling the number of unknowns.Therefore,the exponential matrix methodology is applied to calculate the solution.The temperature field effects are evaluated in the static investigation of shells and plates in terms of displacement and stress components.After an appropriate preliminary validation,new benchmarks are discussed for several thickness ratios,geometrical data,lamination sequences,materials and sovra-temperature values imposed at the outer faces.Results make evident the accordance between the uncoupled thermo-mechanical model and this new full coupled thermo-mechanical model without the need to separately solve the Fourier heat conduction relation.Both effects connected with the thickness layer and the related embedded materials are included in the conducted thermal stress analysis. 展开更多
关键词 Three-dimensional exact thermo-elastic shellmodel full coupled thermoelasticity three-dimensional fourier heat conduction relation plate and shell geometries laminated and sandwich configurations
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Bifurcation and chaos analysis of a nonlinear electromechanical coupling relative rotation system 被引量:1
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作者 刘爽 赵双双 +1 位作者 孙宝平 张文明 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期271-277,共7页
Hopf bifurcation and chaos of a nonlinear electromechanical coupling relative rotation system are studied in this paper. Considering the energy in air-gap field of AC motor, the dynamical equation of nonlinear electro... Hopf bifurcation and chaos of a nonlinear electromechanical coupling relative rotation system are studied in this paper. Considering the energy in air-gap field of AC motor, the dynamical equation of nonlinear electromechanical coupling relative rotation system is deduced by using the dissipation Lagrange equation. Choosing the electromagnetic stiffness as a bifurcation parameter, the necessary and sufficient conditions of Hopf bifurcation are given, and the bifurcation characteristics are studied. The mechanism and conditions of system parameters for chaotic motions are investigated rigorously based on the Silnikov method, and the homoclinic orbit is found by using the undetermined coefficient method. Therefore, Smale horseshoe chaos occurs when electromagnetic stiffness changes. Numerical simulations are also given, which confirm the analytical results. 展开更多
关键词 relative rotation electromechanical coupling Hopf bifurcation CHAOS
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Coupling Between the Group—Related Coherent States
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作者 LIGuang-Hua HEHui-Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第1期1-6,共6页
When two representations of the Lie algebra are coupled, the coupling integral kernels are presented to relate the coupled to uncoupled group-related coherent states. These kernels have a connection with usual couplin... When two representations of the Lie algebra are coupled, the coupling integral kernels are presented to relate the coupled to uncoupled group-related coherent states. These kernels have a connection with usual coupling coefficients. The explicit expressions of these kernels for SU(2), SO(4) and SUq(2) are given. When the direct product of three representations is formed in two ways, the recoupling integral kernels relating to the coupled group-related coherent states corresponding to two different schemes are introduced, and the relations between these kernels and the general recoupling coefficients are obtained. The properties of these kernels are discussed. 展开更多
关键词 群论 相干态 耦合系数
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Dynamic Analysis of Supply and Demand Coupling of Ecosystem Services in Loess Hilly Region:A Case Study of Lanzhou,China 被引量:5
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作者 LI Pengjie LIU Chunfang +1 位作者 LIU Licheng WANG Weiting 《Chinese Geographical Science》 SCIE CSCD 2021年第2期276-296,共21页
The relationship between the supply and demand for ecosystem services(ESs)is a key issue for the rational allocation of natural resources and optimisation of sustainable development capacity.This paper investigateed t... The relationship between the supply and demand for ecosystem services(ESs)is a key issue for the rational allocation of natural resources and optimisation of sustainable development capacity.This paper investigateed the dynamic evolution features of supply and demand of four ESs in Lanzhou of China,namely,water supply,food supply,carbon fixation and soil retention services.The crosssectional data of 2005 and 2017 were used for calculating ESs value and its supply and demand through ArcGIS software,InVEST model,elastic coefficient model and coupling coordination model.Results showed that:1)from 2005 to 2017,the supply of water supply services increased,the demand of soil retention services decreased,and the supply and demand of food supply and carbon fixation services increased.The high-value areas of service supply were mainly distributed in the rocky mountain areas in the southeast and northwest with high vegetation coverage,while the high-value areas of demand were mainly distributed in the urban areas and surrounding areas with high population density.2)There were five different types of coupling relations.Water supply service was dominated by a negative coupling type D,which means that the decrease in demand for ESs has had a positive response on the supply of ESs.Negative coupling type C was the main type of food supply and carbon fixation services,which means that the increase in demand for ESs has had a negative response on the supply of ESs.All three services were supplemented by a positive coupling type A,which means that the increase in demand for ESs has had a positive response on the supply of ESs.Soil retention service generally exhibits a positive coupling type B,which means that the decrease in demand for ESs has had a negative response on the supply of ESs.3)Over the past 12 yr,the coordination degree of supply and demand of water supply,food supply and soil retention services decreased,and the coordination degree of carbon fixation service increased.Various types of ES had a low degree of coupling and coordination,showing different characteristics of temporal and spatial evolution.The areas with imbalanced ESs supply and demand were mainly distributed in urban areas dominated by construction land.The research results are valuable to the optimisation of urban and rural ecological environments and the sustainable development of territory space under the framework of ecological civilisation,including similar ecologically vulnerable areas in other developing countries. 展开更多
关键词 loess hilly region supply and demand of ecosystem services(ESs) coupling coordination degree elastic coefficient coupling relation
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Hopf bifurcation control for a coupled nonlinear relative rotation system with time-delay feedbacks 被引量:1
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作者 刘爽 李雪 +1 位作者 谈书贤 李海滨 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期299-305,共7页
This paper investigates the Hopf bifurcations resulting from time delay in a coupled relative-rotation system with time- delay feedbacks. Firstly, considering external excitation, the dynamical equation of relative ro... This paper investigates the Hopf bifurcations resulting from time delay in a coupled relative-rotation system with time- delay feedbacks. Firstly, considering external excitation, the dynamical equation of relative rotation nonlinear dynamical system with primary resonance and 1:1 internal resonance under time-delay feedbacks is deduced. Secondly, the averaging equation is obtained by the multiple scales method. The periodic solution in a closed form is presented by a perturbation approach. At last, numerical simulations confirm that time-delay theoretical analyses have influence on the Hopf bifurcation point and the stability of periodic solution. 展开更多
关键词 relative rotation coupled nonlinear system BIFURCATION time delay
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Does Industry-University-Research Cooperation Matter? An Analysis of Its Coupling Effect on Regional Innovation and Economic Development 被引量:1
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作者 CUI Zhizhen LI Erling 《Chinese Geographical Science》 SCIE CSCD 2022年第5期915-930,共16页
The dislocation between regional innovation and economic development directly influences the economic effect of regional innovation. However, no in-depth researches have been made on how to solve this problem. Using d... The dislocation between regional innovation and economic development directly influences the economic effect of regional innovation. However, no in-depth researches have been made on how to solve this problem. Using data from Henan Province, China,employing geographical detector technology, this paper focuses on testing whether the industry-university-research cooperation can contribute to coordinating the relation between regional innovation and economic development. It is shown that: 1) the industry-universityresearch cooperation in Henan Province is increasing gradually, and the network presents a core-edge structure, and the coupling degree between regional innovation and economic development is spatially unbalanced, which is similar to the spatial distribution of the intensity of industry-university-research cooperation;2) as an important approach to effectively connect scientific researches with market demands, the industry-university-research cooperation can help form an interactive, interconnected, coupled and coordinated virtuous relation between regional innovation and economic development. Compared with the cooperation between organizations of the same type and the separate innovation of organizations, the improvement of the industry-university-research cooperation level can better coordinate the relation between regional innovation and economic development;3) the cooperative innovation model between enterprises and universities can better promote the coupling between regional innovation and economic development, compared with many industryuniversity-research cooperation models. For underdeveloped areas lacking local knowledge base, industry-university-research cooperation should be considered as a long-term development strategy, especially using the knowledge sources of external universities and scientific research institutions to enhance innovation capability and achieve economic growth. 展开更多
关键词 industry-university-research cooperation regional innovation capability economic development level coupling relation model difference Henan Province China
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Seepage-stress coupling constitutive model of anisotropic soft rock 被引量:2
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作者 张向霞 杨林德 闫小波 《Journal of Central South University》 SCIE EI CAS 2009年第1期149-153,共5页
To provide a seepage-stress coupling constitutive model that can directly describe the seepage-stress coupling relationship, a series of one-dimensional seepage-stress coupling tests on two kinds of soft rock (argilla... To provide a seepage-stress coupling constitutive model that can directly describe the seepage-stress coupling relationship, a series of one-dimensional seepage-stress coupling tests on two kinds of soft rock (argillaceous siltstone and brown mudstone) were performed by using an MTS-815.02 tri-axial rock mechanics test system, with which the stress-strain curves according to the seepage variation were obtained. Based on the experimental results and by employing Hooke's law, the formulation of the coefficient of strain-dependent permeability was presented and introduced to establish a coupling model. In addition, the mathematical expression and the incremental formulation for coupling model were advanced, in which five parameters that can be respectively determined by using the experimental results were included. The calculated results show that the proposed coupling model is capable of simulating the stress-strain relationship with considering the seepage-stress coupling in the nonlinear elastic stage of two kinds of soft rock. 展开更多
关键词 岩石学 渗流应力 岩石力学测试系统 数学表达式 耦合模型
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Galactic Route to the Strong Coupling Constant αs(mz) and Its Implication on the Mass Constituents of the Universe
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2022年第12期3572-3585,共14页
Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum g... Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum galactic rotation velocity by the simple relation , where is the velocity, at which the difference between galactic rotation velocity and Thomas precession is equal, and α is Sommerfeld’s constant. The result is in excellent agreement with the value of α<sub>s</sub> = 0.1170 ± 0.0019, recently measured and verified via QCE analysis by CERN researchers. One can formulate a reciprocity relation, connecting α<sub>s</sub> with the circle constant: . It is the merit of Preston Guynn to derive the Milky Way maximum value of the galactic rotation velocity β<sub>g</sub>, pointing to its “extremely important role in all physics”. The mass (energy) constituents of the Universe follow a golden mean hierarchy and can simply be related to the maximum of Guynn’s difference velocity respectively to α<sub>s</sub>(m<sub>z</sub>), therewith excellently confirming Bouchet’s WMAP data analysis. We conclude once more that the golden mean concept is the leading one of nature. 展开更多
关键词 Strong coupling Constant Sommerfeld’ Constant Gravitational coupling Constant Galactic Velocity Structure-Matter Theory Reciprocity relation Goldem Mean Hierarchy Mass and Energy Constituents of the Universe Superconductivity Matter-Antimatter Asymmetry Unification of Science
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基于Python的平面杆系结构有限元分析
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作者 董军 张尧 +2 位作者 李国华 刘亚立 王秀芳 《兰州理工大学学报》 CAS 北大核心 2024年第2期104-110,共7页
基于Python程序,将杆单元位移不连续、理想刚杆两种力学对象关联统一,开展平面杆系结构有限元模型分析,并实现一种基于“变量标记”的自由度集中处理的计算模式.基于虚功原理引入并推证刚体荷载传递定理,表明耦合单元、刚杆及忽略某一... 基于Python程序,将杆单元位移不连续、理想刚杆两种力学对象关联统一,开展平面杆系结构有限元模型分析,并实现一种基于“变量标记”的自由度集中处理的计算模式.基于虚功原理引入并推证刚体荷载传递定理,表明耦合单元、刚杆及忽略某一自由度的有限元内置算法处理过程中,实质是将单元刚度矩阵进行“刚化”处理.算例分析表明,“变量标记”的计算模式与单元刚度矩阵的“刚化”处理,具有力学模型的普适性和统一性、编程的可行性以及结果的可靠性等特点,能解决平面任意杆系结构的建模问题.研究结果表明,“主从结点”、“刚杆”等建模方法,对于进一步开展有限元二次开发、大变形以及非线性等功能性扩展等有重要的参加价值,证明将Python程序应用于结构有限元分析的可行性. 展开更多
关键词 平面杆系结构 PYTHON 有限元分析 耦合单元 主从关系
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地理学中自然与人文耦合的挑战与前景
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作者 叶超 《热带地理》 CSCD 北大核心 2024年第1期28-31,共4页
进入人类世以来,随着重大自然与社会问题的涌现,作为一门典型的交叉学科,地理学面临着前所未有的挑战与机遇。地理学研究的是复杂交织的人地关系问题,所以需要先在内部摒除二元论的偏见,实现自然(包括GIS)与人文的耦合。对中国地理学而... 进入人类世以来,随着重大自然与社会问题的涌现,作为一门典型的交叉学科,地理学面临着前所未有的挑战与机遇。地理学研究的是复杂交织的人地关系问题,所以需要先在内部摒除二元论的偏见,实现自然(包括GIS)与人文的耦合。对中国地理学而言,自然与人文耦合的关键或难点在于方法论。应对挑战,地理学共同体应该鼓励面向重大问题的、多元化的交叉研究,促进数据、技术与社会的融合,共创治理科学新范式,逐步改变重理轻文的学科评价导向。在全球可持续发展的大背景下,地理学内部的交叉融合以及地理学与其他学科的交叉合作至关重要,人文与自然的耦合是地理学应该始终坚持的方向。 展开更多
关键词 二元论 人地耦合 方法论 可持续发展 治理 自然地理学 人文地理学
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肥大细胞在特应性皮炎发病中的作用及相关治疗进展
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作者 陈玉迪 刘琬 +1 位作者 杨敏 常建民 《中华临床免疫和变态反应杂志》 CAS 2024年第2期174-180,共7页
特应性皮炎(atopic dermatitis,AD)发病机制复杂,多种细胞参与其发病过程。肥大细胞主要分布于皮肤和黏膜,是多种变态反应性疾病的重要效应细胞,但肥大细胞在AD发病机制中的作用尚不完全明确。研究表明,肥大细胞主要通过“IgE-FcεRI-... 特应性皮炎(atopic dermatitis,AD)发病机制复杂,多种细胞参与其发病过程。肥大细胞主要分布于皮肤和黏膜,是多种变态反应性疾病的重要效应细胞,但肥大细胞在AD发病机制中的作用尚不完全明确。研究表明,肥大细胞主要通过“IgE-FcεRI-组胺”途径和“MrgprB2/X2-类胰蛋白酶”途径在AD的发病中发挥作用,同时肥大细胞还释放多种2型炎症相关细胞因子进一步促进AD的免疫失衡。本文主要回顾近年来肥大细胞在AD发病机制中的研究及相关治疗进展,以期为AD的治疗与管理提供新思路。 展开更多
关键词 肥大细胞 特应性皮炎 高亲和力IGE受体 mas相关G蛋白偶联受体
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耦合级联失效系统可靠性建模与分析
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作者 王琦 贾旭杰 +1 位作者 翁宇如 田美玉 《运筹与管理》 CSCD 北大核心 2024年第1期90-94,共5页
现实生活中绝大多数系统并不是孤立存在的,如通信网和电网,它们相互依存、相互影响,这种系统间的耦合关系使得级联失效范围变得更广,导致级联过程更为复杂,从而影响整个系统可靠性及其正常运行。针对此问题,论文以电力通信系统为研究背... 现实生活中绝大多数系统并不是孤立存在的,如通信网和电网,它们相互依存、相互影响,这种系统间的耦合关系使得级联失效范围变得更广,导致级联过程更为复杂,从而影响整个系统可靠性及其正常运行。针对此问题,论文以电力通信系统为研究背景,给出了耦合系统转移率的解析表达,分析了元件负载增加影响元件故障率的级联失效效应和子系统间的相依关系,建立了耦合级联失效系统的可靠性模型,并证明了系统可靠度的计算方法和解析式结果。并且利用一个算例展示了耦合系统发生级联失效的具体过程,以验证该方法的有效性与可行性。本文为基于负载和时间的耦合系统的级联研究提供了新的思路,可拓展至不同的耦合关系、耦合强度以及不同的负载分配模式来进一步研究系统的级联失效过程以及可靠度分析。 展开更多
关键词 相依关系 耦合系统 级联失效 连续时间马尔可夫过程 可靠度
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鄂尔多斯盆地陕北斜坡储层岩石学特征及油气勘探指示——以油房庄北部长6油层组为例
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作者 赵春晨 刘护创 +1 位作者 畅斌 王宁 《地质与资源》 CAS 2024年第3期331-338,309,共9页
为明确鄂尔多斯盆地油房庄北部有利相带和优质储层发育区,推进鄂尔多斯盆地探明储量的进一步扩大,通过岩心薄片观察、岩石矿物成分分析测定等多种手段开展油房庄北部重点层段长6油层组储层的碎屑颗粒组成、填隙物组分等关键特征要素研究... 为明确鄂尔多斯盆地油房庄北部有利相带和优质储层发育区,推进鄂尔多斯盆地探明储量的进一步扩大,通过岩心薄片观察、岩石矿物成分分析测定等多种手段开展油房庄北部重点层段长6油层组储层的碎屑颗粒组成、填隙物组分等关键特征要素研究,并在此基础上分析长6油层组储层的重、轻矿物分布规律,进而探讨物源的指示意义以及油气耦合关系,以期补充该地区关于储层岩石学和物源分析的科研成果.经分析,长6砂岩储层主要为长石砂岩,并见少量岩屑长石砂岩;填隙物的类型多、含量变化大,主要包括黏土胶结物、碳酸盐类胶结物、硅质胶结物等;粒级分布以细砂为主,颗粒磨圆为次棱角状,颗粒分选中等以上占主体;胶结类型以薄膜-孔隙型和孔隙-薄膜型、孔隙型、薄膜型、加大-孔隙型胶结为主.长6砂岩储层标准偏差对粒度平均值图解和重矿物组合、轻矿物组分都揭示了长6油层组时期研究区主要受东北方向物源影响,发育了多期叠置的三角洲前缘水下分流河道砂体,并且由于长距离搬运效应,残余粒间孔、长石溶孔较为发育,长石、绿泥石和高岭石的矿物组合在一定程度上提升了研究区的储层物性,并增加了低阻油藏的渗透性.长61和长62的水下分流河道砂体为研究区的优质储层发育区. 展开更多
关键词 长6储层 长石砂岩 矿物组分 物源指示 油气耦合关系 鄂尔多斯盆地
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江苏省体育产业与信息产业关联融合与耦合协调研究
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作者 周晶 《南京体育学院学报》 2024年第4期22-25,F0002,共5页
江苏省体育产业和信息产业目前的发展规模空前,各自发展势头良好,但产业融合是目前经济高质量发展的新趋势,也是产业转型升级的必然趋势。体育产业与信息产业的融合,更是成为推动两者高质量发展的强大动力。研究结合江苏省近5年体育产... 江苏省体育产业和信息产业目前的发展规模空前,各自发展势头良好,但产业融合是目前经济高质量发展的新趋势,也是产业转型升级的必然趋势。体育产业与信息产业的融合,更是成为推动两者高质量发展的强大动力。研究结合江苏省近5年体育产业与信息产业数据,利用灰色关联分析法,探究体育产业及各子行业和信息产业的融合程度,并进一步利用耦合协调度模型计算两大产业在产业融合过程中的协调程度,结果显示:两大产业融合发展状态良好,整体呈现稳步上升趋势;体育产业内部发展尚有差异,部分子行业尚需加强与信息产业的融合;两大产业从各自独立发展到逐渐协同发展,总体达到良好协调状态。 展开更多
关键词 体育产业 信息产业 产业融合 灰色关联分析 耦合协调
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长三角地区乡村建设与农村物流耦合协调发展研究
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作者 李雯 姚冠新 戴盼倩 《物流科技》 2024年第5期5-9,共5页
乡村建设处于社会主义现代化建设的重要位置,农村物流发展也被大力推进。但农村物流的滞后发展制约了乡村建设的进程,二者发展并非协同并进。文章基于2015—2021年长三角三省的数据,借助熵值法、耦合协调度模型和灰色关联度模型,分析乡... 乡村建设处于社会主义现代化建设的重要位置,农村物流发展也被大力推进。但农村物流的滞后发展制约了乡村建设的进程,二者发展并非协同并进。文章基于2015—2021年长三角三省的数据,借助熵值法、耦合协调度模型和灰色关联度模型,分析乡村建设与农村物流的耦合协调发展状况以及二者耦合效应中的关键因素。结果表明:(1)长三角地区乡村建设和农村物流的综合发展水平总体呈上升趋势;(2)乡村建设与农村物流处于高水平耦合阶段;(3)二者的耦合协调度总体上波动增加;(4)乡村建设与农村物流指标间的相互影响作用极强:乡村建设系统中的水土流失治理面积等、农村物流系统中的农村货运量等共8项指标为影响长三角地区乡村建设与农村物流协调发展的关键因素。 展开更多
关键词 乡村建设 农村物流 耦合协调度模型 灰色关联度模型
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血清sMICA、PCNA、GASP-1、TIMP-1在非小细胞肺癌患者中的表达及相关性分析
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作者 张雅琪 彭程程 +1 位作者 万鸿 王萍 《临床肺科杂志》 2024年第2期271-275,共5页
目的探讨血清可溶性MHC-I类链相关蛋白A(sMICA)、增殖细胞核抗原(PCNA)、G蛋白偶联受体相关分选蛋白1(GASP-1)、组织金属蛋白酶抑制剂1(TIMP-1)在非小细胞肺癌(NSCLC)患者中的表达及与病理分型的相关性。方法2020年7月至2022年8月诊治... 目的探讨血清可溶性MHC-I类链相关蛋白A(sMICA)、增殖细胞核抗原(PCNA)、G蛋白偶联受体相关分选蛋白1(GASP-1)、组织金属蛋白酶抑制剂1(TIMP-1)在非小细胞肺癌(NSCLC)患者中的表达及与病理分型的相关性。方法2020年7月至2022年8月诊治的86例NSCLC患者作为研究对象,并设立为观察组,同期选取43例健康体检者设立为对照组;并根据不同病理分型将观察组分为腺癌组(n=33)和鳞癌组(n=53),对比血清sMICA、PCNA、GASP-1、TIMP-1;并采用Logistic回归模型分析sMICA、PCNA、GASP-1、TIMP-1对非小细胞肺癌的影响;采用ROC曲线模型分析sMICA、PCNA、GASP-1、TIMP-1诊断非小细胞肺癌的AUC、敏感度及特异度。结果观察组的sMICA、PCNA、GASP-1、TIMP-1均高于对照组(P<0.05)。腺癌组的sMICA、PCNA、GASP-1、TIMP-1均高于鳞癌组(P<0.05)。二元Logistic回归模型分析显示,sMICA、PCNA、GASP-1、TIMP-1高表达会对非小细胞肺癌的发生产生影响(P<0.05)。ROC曲线分析显示,sMICA、PCNA、GASP-1、TIMP-1及四项联合诊断NSCLC的AUC值分别为(0.750、0.654、0.819、0.788、0.843,P均<0.05),敏感度分别为57.00%、46.50%、67.40%、90.70%、79.10%;特异度分别为93.00%、93.00%、88.40%、58.10%、86.00%。结论sMICA、PCNA、GASP-1、TIMP-1在NSCLC患者中呈高表达趋势,其表达水平会随病理分型而升高。 展开更多
关键词 血清可溶性MHC-I类链相关蛋白A 增殖细胞核抗原 G蛋白偶联受体相关分选蛋白1 组织金属蛋白酶抑制剂1 非小细胞肺癌 病理分型
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高速铁路大跨度连续斜拉桥上梁端一体化装置性能研究
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作者 周智强 邢书科 +3 位作者 王兆刚 孙洪斌 董昆灵 杨荣山 《铁道标准设计》 北大核心 2024年第4期63-69,87,共8页
目前大跨度斜拉桥上铺设无缝线路,梁端处需设置梁端伸缩装置和钢轨伸缩调节器以降低钢轨产生较大的附加应力,但此结构无法协调较大的梁轨相对位移,应用范围有限。为此,提出了一种梁端一体化装置结构,能适用于较大的梁缝伸缩情况且伸缩... 目前大跨度斜拉桥上铺设无缝线路,梁端处需设置梁端伸缩装置和钢轨伸缩调节器以降低钢轨产生较大的附加应力,但此结构无法协调较大的梁轨相对位移,应用范围有限。为此,提出了一种梁端一体化装置结构,能适用于较大的梁缝伸缩情况且伸缩阻力较小,经过现场应用效果良好。针对时速350 km下高速列车能够平稳通过大跨度斜拉桥无缝线路梁端的要求,建立了相关三维梁端车-线-桥耦合模型,确定了轮轨接触关系,验证该结构在大跨度斜拉桥下对于高速列车平稳运行的适用性。结果表明:温度和梁端转角作用下钢轨会产生一定变形,钢轨垂向变形大于横向变形,最大垂向位移达到15.71 mm。对比仅施加德国低干扰不平顺谱,叠加温度或梁端转角变形后行车过程中的梁端一体化装置动力响应增大,且对钢枕振动垂向加速度的影响较为明显,从38.92 m·s^(-2)上升至48.69 m·s^(-2),增加25.1%。相比之下,极限拉伸状态比极限压缩状态下行车过程中的梁端一体化装置结构响应大,钢枕垂向加速度从40.64 m·s^(-2)上升至62.39 m·s^(-2),增加53.5%,应在高温拉伸状态下对梁端一体化装置性能进行定期检测。梁端一体化装置在以上工况下的响应均满足标准规范要求,本研究可为其在列车高速运行通过大跨度斜拉桥梁端时的铺设提供参考。 展开更多
关键词 高速铁路 铁路桥 连续斜拉桥 无缝线路 钢轨伸缩调节器 梁端一体化装置 车-线-桥耦合 轮轨接触关系 动力响应
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科技创新与海洋经济高质量发展的耦合协调关系研究
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作者 张赛男 周剑 《中国渔业经济》 2024年第3期47-55,共9页
论文基于2010-2021年中国11个涉海省市的面板数据,采用熵权和耦合协调度模型,对科技创新与海洋经济高质量发展进行了综合评价和时空特征分析。研究结果表明:(1)耦合协调度呈现波动增长趋势,地区耦合协调度等级上升了一至三个等级,但整... 论文基于2010-2021年中国11个涉海省市的面板数据,采用熵权和耦合协调度模型,对科技创新与海洋经济高质量发展进行了综合评价和时空特征分析。研究结果表明:(1)耦合协调度呈现波动增长趋势,地区耦合协调度等级上升了一至三个等级,但整体水平偏低,仍有较大进步空间。(2)中国11个沿海省份科技创新与海洋经济高质量发展的耦合协调度表现出显著的区域差异,广东省的耦合度一直处于首部位置,而海南省的耦合度相对最为滞后。(3)将我国沿海省市以区域划分为北方沿海地区和南方沿海地区,南方沿海地区耦合度增长高于北方沿海地区。因此,需加大科技投入,加强环境治理,优化海洋产业结构,发展高附加值产业,还要根据地方实际情况制定符合当地发展需求的措施,以实现区域协调发展。 展开更多
关键词 科技创新 海洋经济高质量发展 熵权 耦合协调关系 海洋强国建设
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Numerical simulation of hypersonic thermochemical nonequilibrium flows using nonlinear coupled constitutive relations
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作者 Shuhua ZENG Zhenyu YUAN +1 位作者 Wenwen ZHAO Weifang CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第3期63-79,共17页
To predict aeroheating performance of hypersonic vehicles accurately in thermochemical nonequilibrium flows accompanied by rarefaction effect,a Nonlinear Coupled Constitutive Relations(NCCR)model coupled with Gupta’s... To predict aeroheating performance of hypersonic vehicles accurately in thermochemical nonequilibrium flows accompanied by rarefaction effect,a Nonlinear Coupled Constitutive Relations(NCCR)model coupled with Gupta’s chemical models and Park’s two-temperature model is firstly proposed in this paper.Three typical cases are intensively investigated for further validation,including hypersonic flows over a two-dimensional cylinder,a RAM-C II flight vehicle and a type HTV-2 flight vehicle.The results predicted by NCCR solution,such as heat flux coefficient and electron number densities,are in better agreement with those of direct simulation Monte Carlo or flight data than Navier-Stokes equations,especially in the extremely nonequilibrium regions,which indicates the potential of the newly-developed solution to capture both thermochemical and rarefied nonequilibrium effects.The comparisons between the present solver and NCCR model without a two-temperature model are also conducted to demonstrate the significance of vibrational energy source term in the accurate simulation of high-Mach flows. 展开更多
关键词 Hypersonic flow Nonlinear coupled constitutive relations Rarefied gas Thermochemical nonequilibrium effect Vibrational excitation
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