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conservation form of Helbing's fluid dynamic traffic flow model

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Applied Mathematics and Mechanics(English Edition) 2011年第9期32卷 1109-1118页

作者：李书峰张鹏 S.c.WONG Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University Department of civil Engineering The University of Hong Kong

A standard conservation form is derived in this *** hyperbolicity of Helbing＇s fluid dynamic traffic flow model is proved,which is essential to the general analytical and numerical study of this *** the basis of this conservation form,a local discontinuous Galerkin scheme is designed to solve the resulting system *** evolution of an unstable equilibrium traffic state leading to a stable stop-and-go traveling wave is *** simulation also verifies that the model is truly improved by the introduction of the modified diffusion coefficients,and thus helps to protect vehicles from collisions and avoide the appearance of the extremely large density.

关键词： conservation form hyperbolicity local discontinuous Galerkin method stop-and-go wave

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改扩建项目可行性研究的竞争力分析

石油化工设计 2004年第4期21卷 35-38页

作者：戴红中国石化上海工程有限公司 200120

以某乙烯改扩建项目为例,论述竞争力分析。以竞争力分析为核心,对项目改扩建的资金投入、建设规模、原料成本、产品成本等,进行了重点分析;项目实施后效益明显。

关键词：竞争力分析改扩建项目产品成本原料成本重点分析可行性研究项目实施乙烯建设规模

MOTIONS OF ALLOYING ADDITIONS IN GAS STIRRED LADLES

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Acta Metallurgica Sinica(English Letters) 2001年第5期14卷 359-367页

作者： S.c. Fan, B.K. Li and J.c. He Department of Thermal Engineering, Northeastern University, Shenyang 110004, china Dept. of Thermal Eng. Northeastern Univ. Shenyang 110004 China

A mathematical model has been developed to analyze the flow patterns and subsurface trajectories of spherical shaped particles (alloy additions) in gas stirring ladles. First, a numerical method to solve fluid flow problems in conjunction with a curvilinear coordinate system is proposed. The internal boundary in flow field, which must be designated in the cylindrical polar coordinate system, can be avoided by using body- fitted coordinate system (BFc). consequently, computed flow of molten steel and paths of alloying additions are able to cross smoothly the geometric centerline of cylindrical vessel. Second, motion of particles is calculated in the three-dimensional coordinate system, the modification of parameters, such as the drag coefficient and density in the gas plume region, is examined. When the density of sphere is closer and closer to that of fluid, the path of motion is longer and longer. If the plug is moved off-centered to the half of radius, the path of sphere is prolonged, and the sphere may go through the geometric centerline of vessel, reach the deeper region. The immersed depths increase with increasing entry velocities.

关键词： alloying addition gas stirring ladle motion

Phase-plane analysis of conserved higher-order traffic flow model

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Applied Mathematics and Mechanics(English Edition) 2012年第12期33卷 1505-1512页

作者：吴春秀宋涛张鹏 S.c.WONG Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai Key Laboratory of Mechanics in Energy Engineering Department of civil Engineering The University of Hong Kong

The phase-plane analysis is used to study the traveling wave solution of a recently proposed higher-order traffic flow model under the Lagrange coordinate system. The analysis identifies the types and stabilities of the equilibrium solutions, and the overall distribution structure of the nearby solutions is drawn in the phase plane for the further analysis and comparison. The analytical and numerical results are in agreement, and may help to explain the simulated phenomena, such as the stop-and-go wave and oscillation near a bottleneck. The findings demonstrate the model ability to describe the complexity of congested traffic.

关键词： traffic flow Lagrange coordinates phase-plane analysis traffic congestionpattern

Transition metal impurities in silicon:computational search for a semiconductor qubit

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npj computational Materials 2022年第1期8卷 1674-1684页

作者： cheng-Wei Lee Meenakshi Singh Adele c.Tamboli Vladan Stevanović colorado School of Mines GoldenCOUSA National Renewable Energy Laboratory GoldenCOUSA

Semiconductors offer a promising platform for physical implementation of qubits,but their broad adoption is presently hindered by limited scalability and/or very low operating *** from the nitrogen-vacancy centers in diamond,our goal is to find equivalent optically active point defect centers in crystalline silicon,which could be advantageous for their scalability and integration with classical *** metal(TM)impurities in silicon are common paramagnetic deep defects,but a comprehensive theoretical study of the whole 3d series that considers generalized Koopmans’condition is *** apply the HSE06(+U)method to examine their potential as optically active spin qubits and identify seven TM impurities that have optically allowed triplet–triplet transitions within the silicon band *** results provide the first step toward silicon-based qubits with higher operating temperatures for quantum ***,these point defects could lead to spin-photon interfaces in silicon-based qubits and devices for mid-infrared free-space communications.

关键词： Transition centers allowed

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苏-27大战F-15

航空知识 2006年第7期 68-70页

作者： 3go-353 Mickey 陈蔡祺

又是一个宁静的夜晚。一切看起来都是非常平常,但在网络的虚拟天空上,一场虚拟的现代空战即将爆发。由于U国发生政变,原本与R国的友谊中断,R国以安定政府为由,强行占领了U国1/3的城市以及机场。M国为了援助政变政府,向U国派出了自己强... 详细信息

又是一个宁静的夜晚。一切看起来都是非常平常,但在网络的虚拟天空上,一场虚拟的现代空战即将爆发。由于U国发生政变,原本与R国的友谊中断,R国以安定政府为由,强行占领了U国1/3的城市以及机场。M国为了援助政变政府,向U国派出了自己强大的兵力。一场虚拟的战争就这样开始了。今天,M国飞行员的任务是:护送c-17运输机到16号机场。由于战线被R国地面部队中断,只好出动这架c-17运输机运送物资。由于情报被R国截获,R国也迅速命令6架苏-27对他们进行偷袭,加速截断16号机场里M国部队的物资支援。游戏时间:早上8:56;地点:20号机场。 6架F-15c已经启动好发动机在停机坪上等待起飞。指挥M方的指挥官正通过麦克风对6名飞行员做最后战术安排。这

关键词：闪光弹干扰丝 AIM 指挥官规避机动

ZMPSTE24的纯合子和复合杂合子突变引起核纤层病变性限制性皮病

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世界核心医学期刊文摘（皮肤病学分册） 2006年第8期2卷 18-19页

作者： Moulson c.L. go G. Gardner J.M. J.H. Miner 朱国兴 Renal Division Box 8126Washington University School of Medicine 660 S. Euclid Ave. St Louis MO 63110 United States Dr.

Restrictive dermopathy (RD) is a lethal human genetic disorder characterized by very tight, thin, easily eroded skin, rocker bottom feet, and joint contractures. This disease was recently reported to be associated with a single heterozygous mutation in ZMPSTE24 and hypothesized to be a digenic disorder (Navarro et al, Lamin A and ZMPSTE24 (FAcE-1) defects cause nuclear disorganization and identify restrictive dermopathy as a lethal neonatal laminopathy. Hum Mol Genet 13:2493- 2503, 2004). ZMPSTE24 encodes an enzyme necessary for the correct processing and maturation of lamin A, an intermediate filament component of the nuclear envelope. Here we present four unrelated patients with homozygous mutations in ZMPSTE24 and a fifth patient with compound heterozygous mutations in ZMPSTE24. Two of the three different mutations we found are novel, and all are single base insertions that result in messenger RNA frameshifts. As a consequence of the presumed lack of ZMPSTE24 activity, prelamin A, the unprocessed toxic form of lamin A, was detected in the nuclei of both cultured cells and tissue from RD patients, but not in control nuclei. Abnormally aggregated lamin A/c was also observed. These results indicate that RD is an autosomal recessive laminopathy caused by inactivating ZMPSTE24 mutations that result in defective processing and nuclear accumulation of prelamin A.

关键词：复合杂合子突变位点纯合子皮病核纤层变性信使RNA 4基因特征表现

china and the United States： The contest for Global Economic Leadership

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china & World Economy 2018年第5期26卷 12-37页

作者： c. Fred Bergsten Peterson Institute for International Economics USA

This paper considers whether there is a ＂Thucydides trap ＂＇ in the world economy, referring to the inherent conflict between incumbent and challenger It assesses the impact of President Trump ~ alienation of traditional US allies, which threatens to splinter the ＂hegemonic coalition ＇＂ and even push china and Europe together, and his convergence toward some chinese norms on trade and even polities. It outlines three possible systemic scenarios： a ＂go＂ in which the US is no longer willing to lead but china is not yet able or willing, and whether such a （likely） regime will be stable or unstable; a new ＂G1, ＂＇ sooner or later, led by china; and a cooperative ＂G2 ＂＂ in which the US and china agree to share leadership. It traces the evolution of actual leadership initiatives of the two countries in recent years. It compares US and chinese attitudes on key systemic issues and concludes with an appraisal of ＂＇an international economic order with chinese characteristics, ＂＂ a worm in which the state plays a greater role relative to market economics, the rule of law defers increasingly to voluntary arrangements, and politics tilt toward central ~overnment control more than democracy.

关键词： G2 global leadership hegemonic coalition trade war

孔源性视网膜脱离的遗传因素一个家族聚集性调查

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美国医学会眼科杂志（中文版） 2006年第3期18卷 191-192页

作者： Sloe Lie go carel B. Hoyng caroline c. W. Klaver 刘亮（译）雷嘉启（校）

目的：对无症状孔源性视网膜脱离患者行家族聚集性调查，分析其中遗传因素的影响。

关键词：孔源性视网膜脱离家族聚集性遗传因素无症状