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Dynamics of air transport networks：A review from a complex systems perspective

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Chinese Journal of Aeronautics 2017年第2期30卷 469-478页

作者： Luis e.C.Rocha Department of Public Health Sciences Karolinska Institutet Stockholm 17177 Sweden Department of Mathematics University of Namur 5000 Belgium

Air transport systems are highly dynamic at temporal scales from minutes to *** dynamic behavior not only characterizes the evolution of the system but also affect the system＇s *** the evolutionary mechanisms is thus fundamental in order to better design optimal air transport networks that benefits companies,passengers and the *** this review,we briefly present and discuss the state-of-the-art on time-evolving air transport *** distinguish the structural analysis of sequences of network snapshots,ideal for long-term network evolution（*** evolution）,and temporal paths,preferred for short-term dynamics（*** evolution）.We emphasize that most previous research focused on the first modeling approach（***-term） whereas only a few studies look at high-resolution temporal *** conclude the review highlighting that much research remains to be done,both to apply already available methods and to develop new measures for temporal paths on air transport *** particular,we identify that the study of delays,network resilience and optimization of resources（aircraft and crew） are critical topics.

关键词： Air transport Airport network Complex network Dynamic network Temporal network

First-principles study of the structural,elastic,electronic,optical,and vibrational properties of intermetallic Pd_2Ga

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Chinese Physics B 2012年第3期21卷 341-348页

作者： Yildirim A Koc H Deligoz e Department of Physics Siirt University Department of Physics Aksaray University

The structural, elastic, electronic, optical, and vibrational properties of the orthorhombic Pd2Ga compound are investigated using the norm-conserving pseudopotentials within the local density approximation in the frame of density functional theory. The calculated lattice parameters have been compared with the experimental values and found to be in good agreement with these results. The second-order elastic constants and the other relevant quantities, such as the Young＇s modulus, shear modulus, Poisson＇s ratio, anisotropy factor, sound velocity, and Debye temperature, have been calculated. It is shown that this compound is mechanically stable after analysing the calculated elastic constants. Furthermore, the real and imaginary parts of the dielectric function and the optical constants, such as the optical dielectric constant and the effective number of electrons per unit cell, are calculated and presented. The phonon dispersion curves are derived using the direct method. The present results demonstrate that this compound is dynamically stable.

关键词： Pd2Ga vibrational properties optical properties elastic constants

Development of Powerful RF Plasma Sources for Present and Future NBI Systems

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Plasma Science and Technology 2004年第1期6卷 2135-2140页

作者： e.Speth NBI-Team Max-Planck-Institut fiir Plasmaphysik 85748 Garching Germany EURATOM-AssociationMax-Planck-Institut fiir Plasmaphysik 85748 Garching Germany EURATOM-Association

This paper deals with the topic of RF plasma sources and their application inhigh-power neutral beam heating systems for nuclear fusion devices. RF sources represent aninteresting alternative to the conventional arc discharge sources. Due to the absence of hotfilaments they exhibit an inherent simplicity both in mechanical and electrical aspects andconsequently offer advantages in terms of cost savings, gain in availability and reliability andreduced maintenance. This renders the RF plasma source attractive for any long pulse (> 10 sec) NBIsystem and in particular for the ITeR NBI system. The latter, however, requires that the RF plasmasource is also capable of delivering negative rather than positive hydrogen ions. In the first partof the paper the types, characteristics and operation experience of RF plasma sources for positiveions in operation are described. The second part is devoted to the development for ITeR NBI: thebasic requirements, physics and technology issues and the present status are discussed.

关键词： neutral beam injection negative ions RF plasma source

Robustness of reinforced gradient-type iterative learning control for batch processes with Gaussian noise

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Chinese Journal of Chemical engineering 2016年第5期24卷 623-629页

作者： Xuan Yang Xiao'e Ruan Department of Applied Mathematics School of Mathematics and StatisticsXi'an Jiaotong University

In this paper,a reinforced gradient-type iterative learning control pro file is proposed by making use of system matrices and a proper learning step to improve the tracking performance of batch processes disturbed by external Gaussian white *** robustness is analyzed and the range of the step is speci fied by means of statistical technique and matrix *** with the conventional one,the proposed algorithm is more ef ficient to resist external *** simulations of an injection molding process illustrate that the proposed scheme is feasible and effective.

关键词： Batch process lterative learning control Reinforced gradient Gaussian white noise

Superplasticity-like creep behavior of coarse grained ternary Al alloys

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Transactions of Nonferrous Metals Society of China 2010年第4期20卷 564-571页

作者：乔军 e.M.TALeFF College of Materials Science and engineering University of Science and Technology Liaoning Department of Mechanical engineering University of Texas at Austin

enhanced tensile ductilities in coarse grained Al-Mg-Zn and Al-Mg-Fe materials were *** materials were Al-2Mg-5Zn,Al-3Mg-5Zn,Al-4Mg-5Zn,Al-3Mg-0.11Fe,Al-3Mg-0.27Fe,and *** elongation-to-failure tests were conducted at constant cross-head speed and constant temperatures from 300 to 450℃.Strain rate change tests were conducted at a constant temperature from 300 to 450℃and in strain-rate range from 4.31×10-5to 1.97×*** results show that over 100%ductilities are consistently achieved in these *** superplasticity-like behavior is rate-controlled by solute-drag *** ternary Zn and Fe additions do not have an adverse effect on solute-drag creep and ductility,they increase stress exponent and its sensitivity to Mg content during solute-drag creep.

关键词： Al-Mg alloys superplasticity solute-drag creep tensile ductility strain-rate sensitivity

Monte Carlo simulation of lattice analysis of complex LaCeTh0.1CuOy using ion bombardment technique

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Nuclear Science and Techniques 2020年第3期31卷 20-34页

作者： M.e.emetere Department of Physics Covenant University Canaanland Department of Mechanical engineering Science University of Johannesburg

Ion bombardment analysis of perovskite materials is challenging owing to their peculiar *** shortcoming renders the reliability on the technique somewhat *** this research,three structured modifications(i.e.,scan angle,low energy,and large ion bombardment)were adopted to improve the ion bombardment analysis of 99,999 ions using Monte Carlo *** modified technique was used to analyze the effects of a chemically pressurized‘‘A’’site in the perovskite lattice *** LaCeTh0.1Cu2Oy compound was used in this *** the low probing energy,it was observed that the high number of ions bombarding the material resulted in external pressure on the lattice structure of the ***,the chemically pressurized‘‘A’’site perovskite material was characterized by lattice mismatch,lattice fluctuations,grain boundary collapse,and oxygen *** novel discovery of this research is the inter-and intra-extended lattice mismatches that are likely to ***,further investigation of the connection between inter-and intraextended lattice mismatches is recommended as they may enable fabrication of room-temperature superconductors.

关键词： Lattice mismatch Ion bombardment Chemical pressure Scan angle

Developmental environment contributes to rapid trait shifts among newly colonized subterranean habitats

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Zoological Research 2023年第4期44卷 808-820页

作者： Nathan e.Swanson Andrew G.Gluesenkamp Alexandra e.Donny Suzanne e.McGaugh Department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSaint PaulMN 55108USA Department of ecology and evolutionary Biology University of California IrvineIrvineCA 92697-2525USA Center for Conservation and Research San Antonio ZooSan AntonioTexas 78212USA ecology Evolutionand BehaviorUniversity of MinnesotaSaint PaulMN 55108USA Department of Biology Stanford UniversityStanfordCA 94305USA

Recent colonization of extreme environments provides unique opportunities to study the early steps of adaptation and the potential for rapid convergent ***,phenotypic shifts during recent colonization may also be due to plasticity in response to changes in the rearing ***,we analyzed a suite of morphological and behavioral traits in paired surface,subterranean,and facultatively subterranean Mexican tetras(Astyanax mexicanus)from recent introductions in two separate watersheds outside of their native *** found a variety of phenotypic and behavioral shifts between subterranean and surface populations that are similar to those observed in relatively ancient populations in *** this rapid morphological divergence,we found that most of these trait differences were due to plasticity in response to rearing *** most trait assays in common-garden,lab-raised fish indicated that phenotypic shifts in wild fish were the result of plasticity,we also found evidence of genetic control in several traits present in subterranean ***,wall-following behavior,an important subterranean foraging behavior,was greater in lab-born subterranean fish than in lab-born surface fish,suggesting rapid divergence of this trait between subterranean and surface ***,this study sheds light on the early steps of subterranean evolution,identifies potential rapid behavioral evolution,and suggests that plasticity in traits involving exploratory behavior may facilitate subterranean colonization.

关键词： Plasticity Adaptation Subterranean Cavefish evolution Common garden

Calculation of resonant sound absorption parameters for performance evaluation of metal rubber material

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Science China(Technological Sciences) 2009年第12期52卷 3587-3591页

作者： e.A.IZZHeUROV Samara State Aerospace University Samara 443086Russia

The first resonant(anti-resonant)frequency and sound absorption coefficient of metal rubber(MR) material are theoretically studied with hard backed samples and with air *** equations of the first resonant and anti-resonant frequencies of MR are deduced from the undamped propagation characteristics of porous *** first resonant and anti-resonance sound absorption coefficients are induced according to the theoretical formula for the acoustic characteristic parameters of MR,and the former is modified while the energy consumption at resonance is taken into *** good agreement between the calculation results of these resonant sound absorption parameters and the experimental results verifies the effectiveness of this calculation method for the performance evaluation of MR as a sound absorption material.

关键词： metal rubber(MR)material resonant sound absorption parameters acoustic characteristic parameters

The role of interleukin-18 in glioblastoma pathology implies therapeutic potential of two old drugs-disulfiram and ritonavir

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Chinese Journal of Cancer 2015年第4期34卷 161-165页

作者： Richard e Kast International Initiative for Accelerated Improvement of Glioblastoma Care Study Center

Based on reporting in the last several years,an impressive but dismal list of cytotoxic chemotherapies that fail to prolong the median overall survival of patients with glioblastoma has prompted the development of treatment protocols designed to interfere with growth-facilitating signaling systems by using non-cytotoxic,non-oncology *** recognition of the pro-mobility stimulus,interleukin-18,as a driver of centrifugal glioblastoma cell migration allows potential treatment adjuncts with disulfiram and *** and ritonavir are well-tolerated,non-cytotoxic,non-oncology chemotherapeutic drugs that are marketed for the treatment of alcoholism and human immunodeficiency virus(HIV) infection,*** drugs exhibit an interleukin-18—inhibiting *** the favorable tolerability profile of disulfiram and ritonavir,the unlikely drug-drug interaction with temozolomide,and the poor prognosis of glioblastoma,trials of addition of disulfiram and ritonavir to current standard initial treatment of glioblastoma would be warranted.

关键词：白细胞介素-18 胶质细胞治疗方案人类免疫缺陷病毒硫病理细胞毒性治疗药物