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Stochastic Economic Dispatch Considering the Dependence of Multiple Wind Farms Using Multivariate Gaussian Kernel Copula

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CSEE Journal of Power and Energy Systems 2022年第5期8卷 1352-1362页

作者： Yantai Lin Tianyao Ji Yuzi Jiang q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Wind farms usually cluster in areas with abundant wind ***,spatial dependence of wind speeds among nearby wind farms should be taken into account when modeling a power system with large-scale wind power *** paper proposes a novel non-parametric copula method,multivariate Gaussian kernel copula(MGKC),to describe the dependence structure of wind speeds among multiple wind *** speed scenarios considering the dependence among different wind farms are sampled from the MGKC by the quasi-Monte Carlo(qMC)method,so as to solve the stochastic economic dispatch(SED)problem,for which an improved meanvariance(MV)model is established,which targets at minimizing the expectation and risk of fuel cost *** this model,confidence interval is applied in the wind speed to obtain more practical dispatch solutions by excluding extreme scenarios,for which the quantile-copula is proposed to construct the confidence interval *** studies are carried out on a modified IEEE 30-bus power system with wind farms integrated in two areas,and the results prove the superiority of the MGKC in formulating the dependence among different wind farms and the superiority of the improved MV model based on quantilecopula in determining a better dispatch solution.

关键词： Multivariate Gaussian kernel copula quasi-Monte Carlo quantile-copula stochastic economic dispatch

Desertification and Re-Afforestation of the Coastal Land in Changjiang County,hainan Island

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Chinese Journal Of Geochemistry 2001年第4期20卷 374-382页

作者： Bi, h. Liu, q. Institute of Resources/Environment Department of Geography Hainan Teachers' College Haikou 571158 China

Changjiang County is located to the northwest of the tailing range of the Wuzhi Mountains on hainan Island, facing the sea and being against the Mountains. From southeast to northwest, it gradually descends in relief from mountain, hill, tableland, terrace to coastal plain. Its sandy coastal line is measured at 44.85 km in length and its rocky coastal line at 7.15 km along the county. The desertified coastal land covers an area of about 61.15 km2, ex tending from hundreds of meters to 3 km in width, of which the active sand land accounts for 5. 333 km2 and the semi-active sand land, 7. 333 km2. The dunes are developed at the rate of 10 - 30 m per year from the seashore toward the *** Forest Departments of hainan Province and Changjiang County have done a series of sand-control experiments. The chief technological measures are as follows: (1) to stabilize the drift sand first to create an adequate condition for afforestation; (2) to plant the big and strong saplings of Casuarin equisetifolia with nutrient bags in deep pits; and (3) to apply new tech niques in 'dry-season planting' to guarantee the quality of afforestation. The above experi ments were successful. however, there still exist some problems such as quite seriously wilting shoot, lower survival rate of Pandanus tectorius in the vertical lines to the usual wind direc tion, monotonous tree species in afforestation and subsequent poor management. Thus some suggestions are offered in this paper for future extension: ( 1 ) to apply REE fertilizers in the process of afforestation to increase the resistance of the plants; (2) to increase the vertical lines of Pandanus tectorius to the usual wind direction to raise their survival rate in the network of sand stabilization; (3) to enlarge the area of liana planting to enhance the stability of sand; (4)to try to introduce new tree species from other regions, which are of good performance in sand stabilization; (5) to interplant the adaptable economic crops

关键词：海南岛海岸带环境管理荒漠化

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青藏高原冰尘微生物对有机质的潜在转化过程

中国科学：地球科学 2024年第6期54卷 2008-2019页

作者：郭泌汐刘勇勤钟旭史权何晨郑强蔡阮鸿青藏高原地球系统与资源环境重点实验室中国科学院青藏高原研究所北京100101 兰州大学泛第三极环境中心兰州730000 Department of Earth Oceanand Atmospheric SciencesUniversity of British ColumbiaVancouverBC V6T 1Z4Canada 中国石油大学重质油国家重点实验室北京102249 厦门大学近海海洋环境科学国家重点实验室厦门361102 厦门大学福建省海洋碳汇重点实验室厦门361005

微生物在冰川碳循环中发挥着重要作用,然而当前缺乏对冰尘微生物参与的溶解性有机质(DOM)转化过程的深入研究.本研究利用了分析化学和微生物生态学的主流手段——超高分辨率的傅里叶变换离子回旋共振质谱(FT-ICR MS)和微生物16S rRNA测... 详细信息

微生物在冰川碳循环中发挥着重要作用,然而当前缺乏对冰尘微生物参与的溶解性有机质(DOM)转化过程的深入研究.本研究利用了分析化学和微生物生态学的主流手段——超高分辨率的傅里叶变换离子回旋共振质谱(FT-ICR MS)和微生物16S rRNA测序技术,分别解析了培养实验中青藏高原龙匣宰陇巴冰川冰尘的DOM分子组成以及微生物群落,并耦联两者构建了复杂微生物参与的冰川DOM转化过程.研究结果表明:在60天的培养实验中,冰尘DOM的生物可利用性随着培养时间的增加而降低,微生物对DOM组分的转化过程可分为三个阶段.在前7天里,微生物选择性降解了具有较高h/Cwa和较低O/Cwa的DOM分子,且群落变化不大;在第15至30天期间,DOM组分保持稳定,但微生物多样性增加;到培养末期, DOM分子在微生物作用下转化为难降解的惰性DOM组分,这些惰性DOM具有更高的芳香指数和O/Cwa、更低的h/Cwa以及含有更多的杂原子.此外,培养实验揭示了冰尘中Cyanobacteria、Bacteroidota、Gammaproteobacteria、Firmicutes和Actinobacteriota等类群协同作用于DOM组分转化,使其变得惰性.本研究揭示了冰尘中微生物转化DOM组分的过程,为理解微生物在冰川有机碳循环中的作用提供了新见解.

关键词：冰尘溶解性有机质微生物降解微生物群落时间变化

Mechanical properties of cocoons constructed consecutively by a single silkworm caterpillar,Bombyx mori

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Acta Mechanica Sinica 2008年第2期24卷 151-160页

作者： S.q.h.ang h.P.Zhao X.q.Feng W.Cui Z.Lin M.q.Xu Department of Engineering Mechanics FML Tsinghua University Beijing 100084 China Department of Sericulture Shandong Agriculture University Tai'an 271018 China Department of Landscape Architecture Human Environment-Biological Polytechnic College. Hengyang 421005 China

Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons.

关键词： Silk Silkworm cocoon Mechanical property Biomimetics

Macroscopic and microscopic mechanical behaviors of climbing tendrils

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Acta Mechanica Sinica 2019年第3期35卷 702-710页

作者： q.Guo J.J.Dong Y.Liu X.h.Xu q.h.qin J.S.Wang Tianjin Key Laboratory of Modern Engineering Mechanics Department of MechanicsTianjin UniversityTianjin 300054China State Key Laboratory of Nonlinear Mechanics (LNM) Institute of MechanicsChinese Academy of ScienceBeijing 100080China Research School of Engineering Australian National UniversityCanberraACT 2601Australia

Tendril-bearing climbing plants must recur to the tendril helices with chiral perversion or dual chirality for climbing and to obtain sun exposure. Despite researchers' prolonged fascination with climbing tendrils since Darwin's time and even earlier, why the soft and slender tendrils can bear heavy loads such as the self-weight of a plant or additional load caused by rain remains elusive. In this paper, we take towel gourd tendrils as an example and investigate the macroscopic and microscopic mechanical behaviors of tendrils through experiments and simulations. Our study indicates that the tendril filament exhibits rubber-like hyperelastic behaviors and can particularly endure large elongation, which is mainly attributed to the superelasticity of the cellulose fibril helix contained in the cell wall. Combination of the tendril helical structure with dual chirality or chiral perversion at a macroscale and a cellulose filament helix at a subcellular level creates superior elasticity for biological species relying on support and climbing. This study provides deep insight into the structure-property relationship of climbing tendrils, and the relationship is useful for the bioinspired design of composite systems with superior elasticity.

关键词： Climbing tendril Mechanical behaviors Structure-property relationship Large elongation

ATOMIC STATES AND BRITTLENESS OF hcp Ti_3Al-ORDERED-TYPE ALLOYS

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 270-276页

作者： h.J. Peng Y.q. Xie College of Chemistry and Chemical Engineering Central South University Changsha 410083 China College of Materials Science and Engineering Central South University Changsha 410083 China

On the basis of the framework of systematic science of alloys （SSA）, the basic information such as states, volumes, and potential energies of characteristic atoms in hcp Ti-Al system have been determined. The average atomic state of the hcp Ti3Al compound consisting of ψ4^Ti and ψ0^Al atoms is 0.75[Ar] （3dn）^0.573 （3dc）^2.1685 （4sc）^0.972 （4sf）^0.3093 ＋ 0.25[Ne] （3sc）^1.32 （3pc）^1.19 （3sf ＋ 3pf）^0.49. The brittleness of the ordered hcp Ti3Al compound has been discussed considering the fundamental factors, which are atomic states, bond networks, potential energy wave planes, and the ratio xTi/xAl. The existence of more pc and more dc directional electrons in the hcp Ti3Al compound lead to considerable brittleness; From bond networks and potential energy wave planes, the hcp Ti3Al compound has poorer ductility than the pure hcp Ti metal and the pure fcc Al metal; The Al-rich hcp Ti3Al ordered type alloys have poorer ductility than the Ti-rich hcp Ti3Al ordered type alloys.

关键词： Ti3Al alloy atomic state brittleness

Dependence of thermodynamic quantities at freeze-out on pseudorapidity and collision energy in p-p collisions at LhC energies

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Chinese Physics C 2024年第10期48卷 235-246页

作者： Murad Badshah Yahia A.h.Obaidat haifa I.Alrebdi M.Waqas Muhammad Ajaz Refka Ghodhbani Department of Physics Abdul Wali Khan University MardanMardan 23200Pakistan Department of Physics College of ScienceUniversity of BishaBisha 61922Saudi Arabia Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityRiyadh 11671Saudi Arabia School of Mathematics Physics and Optoelectronic EngineeringHubei University of Automotive TechnologyShiyan 442002China Department of Computer Sciences Faculty of Computing and Information TechnologyNorthern Border UniversityRafhaSaudi Arabia

The transverse momentum distributions of charged hadrons produced in proton-proton collisions at center-of-mass energies(√s)of 0.9 TeV and 2.36 TeV,as measured by the CMS detector at the Large hadron Collider(LhC),have been analyzed within various pseudorapidity classes utilizing the thermodynamically consistent Tsallis *** fitting procedure resulted in the key parameters,namely,effective temperature(T),non-extensivity parameter(q),and kinetic freezeout volume(V).Additionally,the mean transverse momentum()and initial temperature(T_(i))of the particle source are determined through the fit function and string percolation method,*** alternative method is employed to calculate the kinetic freezeout temperature(T_(0))and transverse flow velocity(β_(T))from ***,thermodynamic quantities at the freezeout,including energy density(ε),particle density(n),entropy density(s),pressure(P),and squared speed of sound(C_(s)^(2)),are computed using the extracted T and *** is also observed that,with a decrease in pseudorapidity,all thermodynamic quantities except V and q *** trend is attributed to greater energy transfer along the mid pseudorapidity.q increases towards higher values of pseudorapidity,indicating that particles close to the beam axis are far from ***,V remains nearly independent of *** excitation function of these parameters(q)shows a direct(inverse)correlation with collision *** ε,n,s,and P show a strong dependence on collision energies at low *** verification of the thermodynamic inequality ε≥3P suggests the formation of a highly dense droplet-like quark-Gluon Plasma(qGP).Additionally,the inequality T_(i)>T>T_(0)is explicitly confirmed,aligning with the evolution of the produced fireball.

关键词： charged hadrons tsallis statistics effective temperature non-extensivity parameter pseudorapidity kinetic freeze-out stage multiple freeze-out scenario qGP qCD matter squared speed of sound

Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole

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上海交通大学学报 2004年第z2期38卷 79-82页

作者： J.L.Song D.J.hu q.C.Wang h.q.Chen h.G.Guo School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.

关键词： alternator claw-pole casting-forging near net forming numerical simulation

Low Frequency Electromagnetic Instability in Unmagnetized Inhomogeneous Dusty Plasmas

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Chinese Physics Letters 2001年第3期18卷 402-404页

作者： S.Mahmood q.h.que h.Saleem NPD PINSTECh P.O.NiloreIslamabadPakistan

The low frequency electromagnetic wave instability in an unmagetized inhomogeneous dusty plasma has been pointed *** has been noticed that there exists a stable mode if the propagation of the wave vector along the density gradient is ***,the mode becomes unstable by including the propagation of the wave in the opposite direction of the density gradient.

关键词： wave inhomogeneous opposite