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Molecular Dynamics Simulation for Grain Boundary Deformation under Tensile Loading Condition

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Journal of Materials Science & Technology 2001年第1期17卷 145-146页

作者： Kim, ys Choi, DY Won, SY Kyungpook Natl Univ Dept Mech Engn Taegu South Korea Kyungpook Natl Univ Grad Sch Mech Engn Taegu South Korea

In this study, MD simulations have been performed to observe the behavior of a grain boundary in an alpha -fe plate under 2-dimensional loading. In MD simulation, the acceleration of every molecule can be achieved from the potential energy and the force interacting between each molecule, and the integration of the motion equation by using Verlet method gives the displacement of each molecule. Initially, four alpha -fe rectangular plates having different misorientation angles of grain boundary were modeled by using the Johnson potential and Morse potential. We compared the potential energy of the grain boundary system with that of the perfect structure model. Also, we could obtain the width of the grain boundary by investigating the local potential energy distribution. The tensile loading for each grain boundary models was applied and the behavior of grain boundary was studied. from this study it was clarified that in the case using Johnson potential, the obvious fracture mechanism occurs along the grain boundary, in the case of Morse potential, the diffusion of the grain boundary appears instead of the grain boundary fracture.

关键词： Simulation Molecular Dynamics Simulation for Grain Boundary Deformation under Tensile Loading Condition

Ship Hull Slamming Analysis with Nonlinear Boundary Element Method

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China Ocean Engineering 1997年第4期12卷 411-418页

作者： Lu, CH He, ys Shanghai Jiao Tong Univ Dept Mech Engn Shanghai 200030 Peoples R China

A boundary element method is developed for calculating the flare ship hull slamming problem. The nonlinear free surface elevation and the linear element assumption are employed. The method has been verified by comparisons with results for the water entry of wedges with various deadrise angles. Numerical results show that the pressure distribution varies greatly with the ship hull with different curvilinear equations, and the slamming features are also different; from the numerical simulation, the authors found that the structural damage of the flare hull might be caused by the increasing hydrodynamic pressure over an extensive area on the flare when the upper part of the flare comes into contact with water.

关键词： slamming boundary element method ship full slamming analysis

POST-BUCKLING AND IMPERfECTION SENSITIVITY Of A COLUMN WITH AN EQUILATERAL TRIANGULAR CROSS-SECTION IN THE PLASTIC RANGE

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Acta Mechanica Solida Sinica 1997年第2期10卷 118-130页

作者： Cheng, ys Lu, WD TONGJI UNIV COLL STRUCT ENGN SHANGHAI 200092 PEOPLES R CHINA E CHINA UNIV TECHNOL DEPT MECH ENGN SHANGHAI 200093 PEOPLES R CHINA

The asymmetric initial post-buckling corresponding to the lowest bifurcation load and the imperfection sensitivity are analysed in detail for a compressed simply supported column with an equilateral triangular cross-section in the plastic range. The effect of elastic unloading is taken into ao count in the analysis. The asymptotic relations, including high order terms, among the load, the amplitude of imperfection and the amplitude of the bifurcation mode ark realized. The results show that the maximum supported load is very sensitive to imperfection.

关键词： column plastic post-buckling imperfection-sensitivity asymptotic expansion

A group priority earliest deadline first scheduling algorithm

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frontiers of Computer Science 2012年第5期6卷 560-567页

作者： Qi LI Wei ba School of Control Science and Engineering Dalian University of TechnologyDalian 116024China Science and Technology on Underwater Test and Control Laboratory Dalian 116013China

In most priority scheduling algorithms, the num- ber of priority levels is assumed to be unlimited. However, if a task set requires more priority levels than the system can support, several jobs must in practice be assigned the same priority level. To solve this problem, a novel group priority earliest deadline first （GPEDf） scheduling algorithm is pre- sented. In this algorithm, a schedulability test is given to form a job group, in which the jobs can arbitrarily change their or- der without reducing the schedulability. We consider jobs in the group having the same priority level and use shortest job first （SJf） to schedule the jobs in the group to improve the performance of the system. Compared with earliest deadline first （EDf）, best effort （BE）, and group-EDf （gEDf）, simu- lation results show that the new algorithm exhibits the least switching, the shortest average response time, and the fewest required priority levels. It also has a higher success ratio than both EDf and gEDf.

关键词： real-time system group priority success ratio,switching

2.5D scattering of incident plane SV waves by a canyon in layered half-space

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 587-595页

作者： ba Zhenning Liang Jianwen Department of Civil Engineering Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety （ Tianjin University） Ministry of Education

This paper presents a 2.5D scattering of incident plane SV waves by a canyon in a layered half-space by using the indirect boundary element method （IBEM）. A free field response analysis is performed to provide the displacements and stresses on the boundary of the canyon where fictitious uniform moving loads are applied to calculate the Green＇s *** for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The free field displacements are added to the fictitious uniform moving loads induced displacements and the total response is obtained. Numerical calculations are performed for a canyon with homogenous and in one layer over bedrock. The effects of the thickness and stiffness of the layer on the amplification are studied and discussed.

关键词： layered half-space canyon plane SV wave amplification scattering surface layer indirect boundaryelement method

The genesis of the slab window-related Arzular low-sulfidation epithermal gold mineralization(eastern Pontides,NE Turkey)

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Geoscience frontiers 2013年第4期4卷 409-421页

作者： Enver Akaryali Necati Tysz Gumushane University Department of Geology Karadeniz Technical University.Department of Geology

The Arzular mineralization is one of the best examples of epithermal gold deposits in the eastern Pontides orogenic belt. The mineralization is hosted by the subduction-related basaltic andesites and is mainly controlled by E W and NE SW trending fracture zones. The main ore minerals are galena. sphalerite, pyrite, chalcopyrite, tetrahedrite and gold. Homogenization temperatures of fluid inclu- sions are between 130 and 295 C for quartz and between 90 and 133 C for sphalerite. Sulphur isotope values obtained fiom pyrite, galena and sphalerite vary between 1.2‰ and 3‰ indicating that sulphur belongs to magmatic origin and was derived from the Lutetian non-adakitic granitic intrusions in the region. Oxygen isotope values are between 15.0‰, and 16.7‰ and hydrogen isotope values are between -87‰ and 91‰ The sulphur isotope thermometer yielded temperatures in the range of 244-291 C for the ore formation. Our results support the hypothesis that the Arzular mineralization is a low-sulfidation epithermal gold deposit associated with non-adakitic subduction- related granitic magmas that were generated by slab window-related processes in a south-dipping subduction zone during the Lutetian.

关键词： Slab windowEpithermal goldIsotopefluid inclusionMineralizationTectonics

The effect of propagation delay on the dynamic evolution of the Bitcoin blockchain

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Digital Communications and Networks 2020年第2期6卷 157-166页

作者： Moustapha ba MODAL’X(Laboratoire de Modélisation aléatoire)of UniversitéParis Nanterre(Paris X) MODAL’X is the Mathematics and Computer Sciences laboratory of UniversitéParis Nanterre(Paris X)ministerial label EA 3454UFR SEGMIdépartement Mathématiques-Informatique200 avenue de la République92000NanterreFrance

This paper analyzes the selfish-mine strategy in the Bitcoin blockchain introduced in 2013 by *** and *** strategy could be used by a colluding pool of miners to earn more than their fair share of the mining revenue and in consequence to force other honest miners to join them to decrease the variance of their revenues and make their monthly revenues more *** is a very dangerous dynamic that could allow the rogue pool of miners to go toward a majority by accumulating powers of news adherents and control the entire *** that the propagation delay of information between any two miners in the network,which is not negligible and follows a normal distribution with mean proportional to the physical distance between the two miners,and a constant variance independent of others'delays,we prove that no guarantee can be given about the success or failure of the selfish-mine attack because of the variability of information propagation in the network.

关键词： Blockchain Bitcoin Mining Selfish-mine attack Propagation delay of information

Synthesis of Sulfur Containing Calixcrown and Its Complexing Properties

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Chinese Chemical Letters 1997年第8期8卷 685-688页

作者： Zheng, ys Huang, ZT CHINESE ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

Sulfur containing calixcrown 1 and 2 are synthesized from bromoethoxycalix[4]arene 3, and their complexing properties are also studied.

关键词： ppm fAB Synthesis of Sulfur Containing Calixcrown and Its Complexing Properties KBr

移植物厚度对角膜内皮失代偿行简易后弹力层角膜内皮移植效果的影响

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中国组织工程研究 2025年第6期29卷 1199-1207页

作者：巴颜红高明宏陈颖欣中国人民解放军北部战区总医院辽宁省沈阳市110000

背景:研究表明较薄移植物视力恢复更快、排斥风险更低,国内缺乏对内皮移植术后不同植片厚度的临床疗效分析,因此,确定最佳移植物厚度对于提高手术疗效至关重要。目的:评价简易后弹力层剥离内皮角膜移植术后不同植片厚度对视力恢复及其... 详细信息

背景:研究表明较薄移植物视力恢复更快、排斥风险更低,国内缺乏对内皮移植术后不同植片厚度的临床疗效分析,因此,确定最佳移植物厚度对于提高手术疗效至关重要。目的:评价简易后弹力层剥离内皮角膜移植术后不同植片厚度对视力恢复及其他预后指标的影响。方法:选取2013年1月至2023年2月在北部战区总医院接受简易后弹力层剥离内皮角膜移植手术治疗的角膜内皮失代偿患者共72例(72眼),其中薄植片组(0.05);③两组患者继发性青光眼、植片免疫排斥、植片移位等术后并发症发生率比较差异无显著性意义(P>0.05);④两组术后1年植片生存率比较差异无显著性意义(93.8%,92.3%,P>0.05);⑤结论:简易后弹力层剥离内皮角膜移植术是一种安全有效的角膜内皮移植手术方式,其术后疗效与传统后弹力层剥离内皮角膜移植术相似,而且植片植入方式更为简便。较薄植片能够更早提供最佳矫正视力,更早完成角膜重塑,因此在治疗角膜内皮失代偿疾病时,优先选择薄移植物来提高恢复时间。

关键词：后弹力层撕除角膜内皮移植术角膜内皮失代偿继发性青光眼植片移位原发移植失败植片排斥角膜内皮细胞数角膜移植