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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

EFFECT OF Mo AND Mo_2C ON ThE MICROsTRUCTURE AND PROPERTIEs OF ThE CERMETs BAsED ON Ti(C,N)

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Acta Metallurgica sinica(English Letters) 2008年第3期21卷 211-219页

作者： s.q. Zhou W. Zhao W.h. Xiong Y.N. Zhou school of Materials science and Engineering Huazhong University of Science and Technology Wuhan 430074 China The University of Waterloo Waterloo ON N2L3G1 Canada

Effect of Mo and Mo2 C on the microstructure and properties of Ti（C,N）-based cermets was investigated in this article. The results have indicated that the weight percentage of Mo from 5 to 10 can reduce Ti（C,N） grain diameter and thickness of the rim, and Ti（C,N） grain can be wetted by Ni-Cu-Mo liquid so as to get small contiguity of Ti（C,N） grain. In that way, the transverse rupture strength of Ti（C,N）-based cermets has reached 1800-1900 MPa; the fracture toughness has been due to 16-18 MPa.m1/2. But 15 wt pct Mo was not more effective on Ti（C,N）-based cermets, because the thickness of the rim becomes larger. In the circumstance of Mo2 C, 5 wt pct Mo2 C was good for microstructure and properties of Ti（C,N）-based cermets, but 11 wt pct Mo2C has resulted in larger contiguity of Ti（C,N） grain and big Ti（C,N） grain diameter so as to reduce transverse rupture strength and fracture toughness. so that, the effect of Mo on Ti（C,N）-based cermets is better than Mo2C.

关键词： Cermet Transverse rupture strength (TRs) Contiguity Fracture toughness

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： shan Ping Yu Emily Choi Michael qJiang Ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

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

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

Corrosion behavior of 13Cr stainless steel under stress and crevice in high pressure CO_(2)/O_(2)environment

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Journal of Materials science & Technology 2021年第29期88卷 79-89页

作者： G.Y.Zhu Y.Y.Li B.s.hou q.h.Zhang G.A.Zhang Key Laboratory of Material Chemistry for Energy Conversion and storage Ministry of EducationHubei Key Laboratory of Materials Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

In this work,through the self-developed setup for in situ electrochemical tests,the corrosion behavior of 13 Cr stainless steel under the combined effect of stress and crevice in high pressure CO_(2)/O_(2)environment was *** results show that 13 Cr stainless steel presents a self-passivation *** the action of stress,the anodic dissolution process of steel inside crevice is *** is a galvanic effect between the stressed steel inside crevice and the unstressed steel outside *** applied stress reduces the induction stage of crevice corrosion and induces a larger galvanic current,i.e.,the applied stress promotes the development of crevice ***,adding 0.1 MPa O_(2)is conducive to forming a more stable passive film but causes a greater galvanic effect.

关键词： stainless steel Crevice corrosion stress corrosion Galvanic effect

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

Effect of Mo on microstructural characteristics and coarsening kinetics of γ' precipitates in Co–Al–W–Ta–Ti alloys

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Journal of Materials science & Technology 2018年第5期34卷 799-805页

作者： h.J.Zhou F.Xue h.Chang q.Feng state Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing National Center for Materials service safety University of Science and Technology Beijing

The solvus temperature,volume fraction,coarsening behavior of γ＇ precipitates and the partitioning behavior of alloying elements as well as lattice misfit of γ/γ＇ phases influence the creep behavior of Ni-and Co-base ***,few investigations about the microstructural characteristics and the coarsening behavior of γ＇ precipitates were reported in multicomponent novel Co-base superalloys during thermal *** alloys containing different contents of molybdenum and tungsten have been investigated to explore the effect of molybdenum on γ＇ solvus temperature,γ ＋γ＇ microstructure and γ＇ coarsening in Co–Al–W–Ta–Ti-base *** results showed that the γ＇ solvus temperature decreases with the addition of *** addition reduces the Y＇ volume fractions after aging above 1000℃,but results in negligible influence on the γ＇ volume fractions aging at 900℃.Meanwhile,γ＇ coarsening is controlled by diffusion in experimental alloys after aging at 900℃ and 1000℃,and the kinetics of Y＇growth in experimental alloys are consistent with the predictions of LsW theory.

关键词： Cobalt alloys Molybdenum Coarsening Microstructure

A Diagram for Glass Transition and Plastic Deformation in Model Metallic Glasses

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Journal of Materials science & Technology 2014年第6期30卷 546-550页

作者： X.q.Gao W.h.Wang h.Y.Bai Institute of Physics Chinese Academy of Sciences

In this paper, we report a strain rate related glass transition in model srCaYbMg（Li）Zn（Cu） metallic glasses at room temperature. A critical strain rate, equivalent to glass transition temperature, is found for the strain rate induced glassy state to liquid-like viscoplastic state translation. The results show that the observation time, equivalent to temperature and stress, is a key parameter for the transition between the glass and supercooled liquid states. A three-dimension glass transition diagram involved in time, temperature and stress in metallic glasses is established.

关键词： homogeneous plastic flow Glass transition Metallic glass