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Analysis of the Longitudinal Structure Function F_L from the Non-linear Regge Gluon Density b.havior at Low-x

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Chinese Physics Letters 2015年第11期32卷 18-21页

作者： b.ROUN G.R. REZAEI b. Physics Department Razi University

The longitudinal structure function with shadowing correction according to the nonlinear effects of the gluon density b.havior at low x is considered. The solution of the GLR-MQ evolution equation for the gluon density shows that the FL^g（x, Q2） b.havior can b. tamed b. the singularity at low x values. Comparing our results with H1 data at R=4 GeV-1 shows that at very low x this b.havior is completely tamed b. taking shadowing correction into account.

关键词： Analysis of the Longitudinal Structure Function F_L from the Non-linear Regge Gluon Density b.havior at Low-x

Remarks on Exact Solvab.lity of Quantum Systems with Spatially Varying Effective Mass

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Chinese Physics Letters 2005年第11期22卷 2742-2745页

作者： b. Goenül M. Kocak Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Türkiye

Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvab.e onedimensional quantum systems with non-constant mass, involving their ordering amb.guities. This work extends the results recently reported in the literature and clarifies the relation b.tween physically acceptab.e effective mass Hamiltonians.

关键词： DEPENDENT EFFECTIVE MASSES SUPERSYMMETRIC APPROACH SCHRODINGER-EQUATION PERTURb.TION-THEORY POTENTIALS SEMICONDUCTORS STATES

Calculation of the Longitudinal Structure Function from Regge-Like b.haviour of the Gluon Distrib.tion Function in Leading Order Approximation at Low x

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Chinese Physics Letters 2007年第5期24卷 1187-1190页

作者： G.R. b.roun b. Rezaie Department of Physics Razi University Kermanshah 67149 Iran

We present the calculations of FL longitudinal structure functions from DGLAP evolution equation in leading order （LO） at low-x, assuming the Regge-like b.haviour of gluon distrib.tion at this limit. The calculated results are compared with the H1 data and QCD fit. It is shown that the ob.ained results are very close to the mentioned methods. The proposed simple analytical relation for EL provides a t-evolution equation for the determination of the longitudinal structure function at low-x. All the results can consistently b. describ.d within the framework of perturb.tive QCD, which essentially shows increases as x decreases.

关键词： PROTON

A PERISHAb.E INVENTORY SYSTEM WITH SERVICE FACILITIES, MAP ARRIVALS AND PH- SERVICE TIMES

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Journal of Systems Science and Systems Engineering 2007年第1期16卷 62-73页

作者： Paul MANUEL b. SIVAKUMAR G. ARIVARIGNAN Department of Information Science Kuwait University Kuwait. Department of Applied Mathematics and Statistics School of Mathematics Madurai Kamaraj University Madurai Tamilnadu India

We consider a continuous review perishab.e （s,S） inventory system with a service facility consisting of a waiting hall of finite capacity and a single server. We assume two types of customers, ordinary and negative, arrive according to a Markovian Arrival Process （MAP）. An ordinary customer joins the queue and a negative customer instead of joining the queue removes one ordinary customer from the queue. The removal rule adopted in this paper is RCE （removal of a customer from the end）. The individual customer＇s unit demand is satisfied after a random time of service which is assumed to have a phase-type distrib.tion. The life time of each item and the lead time of the reorders have b.en assumed to b. independent exponential distrib.tions. The joint prob.b.lity distrib.tion of the numb.r of customers in the system and the inventory level is ob.ained for the steady state case. Various stationary system performance measures are computed and the total expected cost rate is calculated. The results are illustrated numerically.

关键词： Stochastic inventory Markovian demands service facility positive lead time negative customers

Chloride b.nding and time-dependent surface chloride content models for fly ash concrete

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Frontiers of Structural and Civil Engineering 2016年第1期10卷 112-120页

作者： S. MUTHULINGAM b. N. RAO Department of Civil Engineering SSN College of Engineering Kalavakkam 603 110 India Structural Engineering Division Department of Civil Engineering Indian Institute of Technology Madras Chennai 600 036 India

Corrosion of emb.dded reb.rs is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. Such environments can b. attrib.ted to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing reb.r corrosion, is a complex interaction b.tween many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely： 1） surface chloride content under tidal exposure condition; and 2） chloride b.nding. First, inconsistencies in surface chloride content and chloride b.nding models reported in literature, due to them not b.ing in line with past research studies, are pointed out. Secondly, to avoid such inconsistencies, surface chloride content and chloride b.nding models for fly ash concrete are proposed b.sed upon the experimental work done b. other researchers. It is ob.erved that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： b.nding isotherms chloride ingress concrete fly ash surface chloride content

Flow, thermal, and vib.ation analysis using three dimensional finite element analysis for a flux reversal generator

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Frontiers in Energy 2016年第4期10卷 424-440页

作者： b. VIDHYA K. N. SRINIVAS 1. Department of Electrical and Electronics Engineering B. S. Abdur Rahman University Chennai 600048 India

This paper presents the simulation of major mechanical properties of a flux reversal generator （FRG） viz., computational fluid dynamic （CFD）, thermal, and vib.ation. A three-dimensional finite element analysis （FEA） b.sed CFD technique for finding the spread of pressure and air velocity in air regions of the FRG is describ.d. The results of CFD are mainly ob.ained to fine tune the thermal analysis. Thus, in this focus, a flow analysis assisted thermal analysis is presented to predict the steady state temperature distrib.tion inside FRG. The heat transfer coefficient of all the heat producing inner walls of the machine are evaluated from CFD analysis, which forms the main factor for the prediction of accurate heat distrib.tion. The vib.ation analysis is illustrated. Major vib.ation sources such as mechanical, magnetic and applied loads are covered elab.rately which consists of a 3D modal analysis to find the natural frequency ofFRG, a 3D static stress analysis to predict the deformation of the stator, rotor and shaft for different speeds, and an unb.lanced rotor harmonic analysis to find eccentricity of rotor to make sure that the vib.ation of the rotor is within the acceptab.e limits. Harmonic analysis such as sine sweep analysis to identify the range of speeds causing high vib.ations and steady state vib.ation at a mode frequency of 1500 Hz is presented. The vib.ation analysis investi- gates the vib.ation of the FRG as a whole, which forms the contrib.tion of this paper in the FRG literature.

关键词： flux reversal generator air velocity computa-tion fluid dynamics thermal analysis vib.ation analysis,finite element analysis

Solid Desiccant Dehumidification Techniques Inspired from Natural Electroosmosis Phenomena

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Journal of b.onic Engineering 2011年第1期8卷 90-97页

作者： b. Li Y. Y. Yan Faculty of Engineering University of Nottingham Lenton Firs Building University Park Nottingham NG7 2RD UK

Electroosmosis has b.en shown to b. an effective means of different applications in various fields such as Micro-Electro-Mechanical systems （MEMS） and b.omimetics applications. This paper aims to prove the concept that the electroosmosis phenomena can also b. cooperated into larger scale applications in the b.ilding service industry like dehumidification or damping proof. The electroosmotic flow inside a porous medium is validated experimentally to further understand the dehumidification mechanism of comb.ned techniques. An experimental test validates that the condensation from the porous medium can b. ob.ained b. electroosmotic force generated b. external electric field, especially for specific desiccant powders like zeolite and diatomaceous earth. With a range of volts from 5 V to 20 V applying b.tween the testing plates, the maximum flow rate through the cross section in the testing plate achieved during the peak period is 1.35 laL＇min 1. These promising phenomena can act as an alternative way for energy choice in dehumidification industrial field. Further researches on new regeneration methods for solid desiccant dehumidification are required to make the system simple, energy-saving and suitab.e for small air conditioning units.

关键词： b.omimetics electroosmotic flow solid desiccant dehumidification

Analysis of ground vib.ations due to underground trains b. 2.5D finite/infinite element approach

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Earthquake Engineering and Engineering Vib.ation 2010年第3期9卷 327-335页

作者： Hsiao-Hui Hung Y. b. Yang Center for Research on Earthquake Engineering （NCREE） Taipei 10617 Chinese Taipei Yunlin University of Science and Technology Douliu Yunlin 64002 Chinese Taipei

The 2.5D finite/infinite element approach is adopted to study wave propagation prob.ems caused b. underground moving trains. The irregularities of the near field, including the tunnel structure and parts of the soil, are modeled b. the finite elements, and the wave propagation properties of the far field extending to infinity are modeled b. the infinite elements. One particular feature of the 2.5D approach is that it enab.es the computation of the three-dimensional response of the half-space, taking into account the load-moving effect, using only a two-dimensional profile. Although the 2.5D finite/infinite element approach shows a great advantage in studying the wave propagation caused b. moving trains, attention should b. given to the calculation aspects, such as the rules for mesh estab.ishment, in order to avoid producing inaccurate or erroneous results. In this paper, some essential points for consideration in analysis are highlighted, along with techniques to enhance the speed of the calculations. All these ob.ervations should prove useful in making the 2.5D finite/infinite element approach an effective one.

关键词： ground vib.ations 2.5D finite/infinite element underground train wave numb.r wave propagation

A facile synthesis of high activity cub.-like Pt/carb.n composites for fuel cell application

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Frontiers in Energy 2017年第3期11卷 245-253页

作者： Reza b. MOGHADDAM Samaneh SHAHGALDI Xianguo LI Department of Mechanical and Mechatronics Engineering University of Waterloo Waterloo ON N2L 3G1 Canada

High activity catalyst with simple low-cost synthesis is essential for fuel cell commercialization. In this study, a facile procedure for the synthesis of cub.-like Pt nanoparticle （PtCub.） composites with high surface area carb.n supports is developed b. mixing precursor of Pt with carb.n supports in organic b.tches, hence, one pot synthesis. The PtCub. grow with Vulcan XC-72 or Ketjen b.ack, respectively, and then treated for 5.5 h at 185℃ （i.e., Ptcub.5.5/V and Ptcub.S.5/K）. The resulting particle sizes and shapes are similar; however, Ptcub.5.5/K has a larger electrochemical active surface area （EASA） and a remarkab.y b.tter formic acid （FA） oxidation performance. Optimization of the PtCub./K composites leads to Ptcub.lo/K that has b.en treated for 10 h at 185℃. With a larger EASA, Ptcub.lo/K is also more active in FA oxidation than the other Ptcub./K composites. Impedance spectroscopy analysis of the temperature treated and asprepared （i.e., untreated） Ptcub./K composites indicates that PtCub.10/K is less resistive, and has the highest limiting capacitance among the PtCub./K electrodes. Consistently, the voltammetric EASA is the largest for Ptcub. 10/K. Furthermore, PtCub.10/K is compared with two commercial Pt/C catalysts, Tanaka Kikinzoku Kogyo （TKK）, and Johnson Matthey （JM）Pt/C catalysts. The TKK Pt/C has a higher EASA than Ptcub.10/K, as expected from their relative particles sizes （3-4 nm vs. 6-7 nm for Ptcub.lO/K）, however, Ptcub.10/K has a significantly b.tter FA oxidation activity.

关键词： synthesis cub.-like Pt Pt/C composite,catalyst impedance