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Chinese Physics Letters 2016年第3期33卷 56-59页

作者： s.h.Kim Church Road 9236 Dallas Texas 75231 USA

We consider the radiation from the beam electrons traveling in a strong uniform axial magnetic field and an axial alternating electric field of wavelength Aw generated by a voltage-supplied pill-box cavity. The beam electrons emit genuine laser radiation that propagates only in the axial direction through free-electron two- quantum stark radiation. We find that laser radiation takes place only at the expense of the axial kinetic energy when Aw 〈〈 c/（ωc/γ）, where ωc/γ is the relativistic electron--cyclotron frequency. We formulate the laser power based on quantum-wiggler electrodynamics, and envision a laser of length lore with estimated power 0.1 GW/（kA） in the 10-4 cm wavelength range.

关键词： of on in that Electron-Cyclotron Laser Using Free-Electron Two-Quantum stark Radiation in a strong Uniform Axial Magnetic Field and an Alternating Axial Electric Field in a Voltage-supplied Pill-Box Cavity is stark

Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun huang Bin Jia Artem s.Pilipchuk sibo huang Chen shen Almas F.sadreev Yong Li Andrey E.Miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonhermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge hernández-Campano sergei A.Kirov Jesús M.hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for health Research(IRYCIs) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

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X公司的招聘和选拔流程优化研究

X公司的招聘和选拔流程优化研究

作者： naqib Yussof 上海外国语大学

学位级别：硕士

组织的成功取决于其员工的有效性。没有高素质的劳动力,一个组织注定要有平庸的表现。组织的招聘和选拔实践是人力资源管理最重要的职能之一。招聘和选拔劳动力市场中最优秀的人才涉及各种人力资源管理活动。招聘和选拔作为一种人力资... 详细信息

组织的成功取决于其员工的有效性。没有高素质的劳动力,一个组织注定要有平庸的表现。组织的招聘和选拔实践是人力资源管理最重要的职能之一。招聘和选拔劳动力市场中最优秀的人才涉及各种人力资源管理活动。招聘和选拔作为一种人力资源管理职能,是在实现其最终目标方面最关键地影响组织绩效的活动之一(Costello,2006)。根据Beer等人(1984)的说法,招募和选拔不仅试图吸引,获得和保留组织实现战略目标所需的人力资源的数量和质量,而且还可能对其组成产生重大影响。劳动力,员工与组织的需求和文化以及长期就业稳定性的最终契合。有效利用招聘和甄选政策和做法也可以改善员工的承诺和绩效,并减少他们的缺勤率和离职率。该研究的主要目的是确定X公司现有的招聘和选拔实践。该公司总部设在上海,本研究的重点是招聘和选择两个非常重要的职位X公司,即业务发展经理和财务顾问。由于公司业务的性质,这两个职位主要由外国人才占据。通过识别公司遇到的挑战,并提供优化策略和建议,以改善他们的招聘和选拔过程。本研究报告还回顾了有关招募和选拔的文献。X公司使用外部和内部招聘来源。它将讨论五个理论框架:人力资本理论,资源依赖理论,五大人格理论,印象管理理论和荷兰职业倾向理论。它使用PEsT分析来评估影响公司招聘和选择过程的外部因素。调查问题用于确定受访者对X公司员工招聘和选拔实践的当前问题的看法。然后分析从调查中获得的数据。研究结果显示,有五种主要的招募和选择方法。按照高度认可的方法排名前三位最常用的员工选择媒介包括在线广告,员工推荐和校园招聘。还得出大多数员工只在X公司工作不到一年-这表明公司的员工流动率很高。确定了五个关键问题和问题,即时间限制,招聘和选拔过程的复杂性,招聘过程的低效率,找到想要搬迁和吸引合适候选人的人。还有人透露,法律,政治和社会文化因素等环境因素通常会影响选拔过程。虽然组织必须制定适合其个人需求的招聘和甄选计划,但他们必须采用有效的评估方法,以确保他们所实施的程序尽可能高效和有效。满足这些需求。在文献综述中强调了评估的重要性,因为组织必须了解他们是否真正从他们现有的程序中获益。但是,通过返回的调查和进行的访谈确定,目前该组织没有适当的程序来评估招聘教师时招聘和选拔方法的有效性。强烈建议在不久的将来,组织引入诸如文献综述中提出的措施,以评估其招聘和选拔过程的有效性。这不仅有助于组织满足其人员需求,而且还将促进区域运营管理人员建立正确和错误的方法

关键词： X公司人力资源招聘与选拔 PEsT分析优化策略

A control volume based finite element method for simulating incompressible two-phase flow in heterogeneous porous media and its application to reservoir engineering

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Petroleum science 2012年第4期9卷 485-497页

作者： sADRNEJAD s A GhAsEMZADEh h GhOREIshIAN AMIRI s A MONTAZERI G h Faculty of Civil Engineering K.N.Toosi University of Technology Research and Development Department Iranian Central Oil Field Co.

Applying the standard Galerkin finite element method for solving flow problems in porous media encounters some difficulties such as numerical oscillation at the shock front and discontinuity of the velocity field on element *** of velocity field leads this method not to conserve mass ***,the accuracy and stability of a solution is highly affected by a non-conservative *** this paper,a three dimensional control volume finite element method is developed for twophase fluid flow simulation which overcomes the deficiency of the standard finite element method,and attains high-orders of accuracy at a reasonable computational ***,this method is capable of handling heterogeneity in a very rational way.A fully implicit scheme is applied to temporal discretization of the governing equations to achieve an unconditionally stable *** accuracy and efficiency of the method are verified by simulating some waterflooding *** representative examples are presented to illustrate the capability of the method to simulate two-phase fluid flow in heterogeneous porous media.

关键词： Finite element method control volume two-phase flow heterogeneity porous media waterflooding

Application of control volume based finite element method for solving the black-oil fluid equations

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Petroleum science 2013年第3期10卷 361-372页

作者： GhOREIshIAN AMIRI s A sADRNEJAD s A GhAsEMZADEh h MONTAZERI G h Faculty of Civil Engineering K. N. Toosi University of TechnologyTehran Iran Research and Development Dept. Iranian Central Oil Field Co.Tehran Iran

This is the second paper of a series where we introduce a control volume based finite element method （CVFEM） to simulate multiphase flow in porous media. This is a fully conservative method able to deal with unstructured grids which can be used for representing any complexity of reservoir geometry and its geological objects in an accurate and efficient manner. In order to deal with the inherent heterogeneity of the reservoirs, all operations related to discretization are performed at the element level in a manner similar to classical finite element method （FEM）. Moreover, the proposed method can effectively reduce the so-called grid orientation effects. In the first paper of this series, we presented this method and its application for incompressible and immiscible two-phase flow simulation in homogeneous and heterogeneous porous media. In this paper, we evaluate the capability of the method in the solution of highly nonlinear and coupled partial differential equations by simulating hydrocarbon reservoirs using the black-oil model. Furthermore, the effect of grid orientation is investigated by simulating a benchmark waterflooding problem. The numerical results show that the formulation presented here is efficient and accurate for solving the bubble point and three-phase coning problems.

关键词： Control volume based finite element,black-oil model grid orientation porous media

OsCILLATION AND GLOBAL ATTRACTIVITY OF IMPULsIVE PERIODIC DELAY REsPIRATORY DYNAMICs MODEL

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Chinese Annals of Mathematics,series B 2005年第4期26卷 511-522页

作者： s.h.sAKER Department of Mathematics Faculty of ScienceMansoura UniversityMansoura 35516Egypt

This paper studies the nonlinear delay impulsive respiratory dynamics model. The model describes the sudden changes of the concentration of CO2 in the blood of the mammal. It is proved that the model has a unique positive periodic solution. somesufficient conditions for oscillation of all positive solutions about the positive periodic solution are established and also some sufficient conditions for the global attractivityof the periodic solution are obtained.

关键词： Periodic solutions Oscillation Global attractivity Respiratory dynamics model Impulsive differential equation

ON ThE GLOBAL sTABILITY CONJECTURE OF ThE GENOTYPE sELECTION MODEL

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Acta Mathematica scientia 2011年第2期31卷 512-528页

作者： s.h. saker Department of Mathematics King Saud University Department of Mathematics Faculty of Science Mansoura University

In 1994, Grove, Kocic, Ladas, and Levin conjectured that the local stability and global stability conditions of the fixed point -y= 1/2 in the genotype selection model should be equivalent. In this article, we give an affirmative answer to this conjecture and prove that local stability implies global stability. some illustrative examples are included to demonstrate the validity and applicability of the results.

关键词： Local stability global stability discrete genotype selection model

stable isotopic analysis on ancient human bones in Jiahu site

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science China Earth sciences 2007年第4期50卷 563-570页

作者： s.h.AMBROsE Lab of Biogeochemistry Department of Anthropology University of Illinios Urbana-Champaign Urbla 61801 USA

Palaeodietary analysis is one of important topics in bioarchaeology field and has been paid great at- tention to by Chinese archaeometrists recently. Ancient human bones in Jiahu site were analyzed by means of stable isotopes of C, N and O. 13 human bones were excluded from 28 bones for dietary re- construction due to their unusual collagen contents, C and N contents, and C/N atomic ratios espe- cially. δ 13C (-20.37±0.53‰) in collagen of remaining samples showed that C3 food were consumed mainly, which is consistent of the archaeological findings that rice was the staple in Jiahu. According to the difference of δ 15N and δ 13C values in bone collagen, the samples can be classified into four clusters. The changes of δ 15N values in bone collagen and δ 13C values in hydroxylapatite through whole cultural phases indicated the transition from hunting to gathering and fishing to rice agriculture and animal domestication ultimately. Meanwhile, the δ 18O change in hydroxylapatite showed that pa- laeoclimate was relatively constant during Jiahu culture.

关键词： palaeodietary analysis stable isotopic analysis Jiahu site rice agriculture animal domestication

Anomalously strong scattering of spontaneously Produced Laser Radiation in the First Free-Electron Laser and study of Free-Electron Two-Quantum stark Lasing in an Electric Wiggler with Quantum-Wiggler Electrodynamics

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Chinese Physics Letters 2006年第6期23卷 1422-1425页

作者： s. h. Kim Department of Physics University of Texas at Arlington PO Box 19059 Arlington Texas 76019 USA

We calculate the scattering cross section of an electron with respect to the spontaneously produced laser radiation in the first free-electron laser （FEL） with quantum-wiggler electrodynamics （QWD）. The cross section is 1016 times the Thomson cross section, confirming the result obtained by a previous analysis of the experimental data. A QWD calculation show that spontaneous emission in an FEL using only an electric wiggler can be very strong while amplification through net stimulated emission is practically negligible.

关键词： CLAssICAL ELECTRODYNAMICs RELATIVIsTIC ELECTRONs ThERMODYNAMICs EXPLANATION EMIssION