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Green Resource Allocation for Multiple OFdMA Based Networks: A Survey

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journal of Electronic Science and Technology 2016年第2期14卷 170-182页

作者： A.S.Khan j.Abdullah H.Lenando j.M.Nazim Facutly of Computer Science and Information Technology Universiti Malaysia Sarwak

Orthogonal frequency division multiple access （OFdMA） is a popular and widely accepted multiple access technique to provide high data rate services in a mobile environment in the area of wireless communications. OFdMA can provide better flexibility in allocating the radio spectra by utilizing subcarrier allocations, scheduling, and energy control to obtain multi-dimension diversity gains. due to its resource allocation flexibility, OFdMA has been widely used as a green air interface technology for the emerging broadband wireless access networks. This paper extensively addresses the integration of green OFdMA to the future air interface technologies, for instance： two-tier cellular, multi radio access technologies （RATs）, FemtoCell, and relay networks. The main focus of the paper is to review and analyze the current OFdMA techniques to address the green resource allocation in multiuser diversity, where the critical constraints are the computational complexity, energy efficiency, and the sub-channel assignment. The future trend of OFdMA based networks will aim to maximize the energy efficiency of the exclusive channel assignment through a joint sub-channel and power allocation to accommodate high data traffic networks specially the relay based 5G cellular networks.

关键词： dynamic multiuserorthogonai frequency division multiple accessresource allocation subcarriers. diversity,(OFdMA),

New 0d/1d Physical Approach for Modelling the Gas dynamics Behavior Inside the Intake System of an Engine

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journal of Thermal Science 2018年第4期27卷 394-403页

作者： david CHALET Mohamad YASSINE jérome MIGAUd Ecole Centrale de Nantes LHEEA lab. (ECN/CNRS) Nantes France MANN+HUMMEL France Laval France

The competition among carmakers to introduce the most innovative solutions is growing day by day. Since few years, simulation is being used widely in automotive industries. Instead of building costly prototypes and expending fuel for doing tests on a real engine, simulation became a good solution before taking new decisions. Concerning the study of gas dynamics and pressure wave's propagation in the intake system of an internal combustion engine, a precise modelling is needed in order to obtain good results. Unfortunately, the computational time for these simulations is considered as high compared to the real time. The main objective of the new approach presented in this paper, is to reduce simulation time of models in the internal combustion engine simulation code, allowing them to accomplish many engine simulations faster than one-dimensional non-linear approach. A transfer function is defined to link directly the relative pressure and the air mass flow rate. In a second time, the model is included into an internal combustion engine simulation code. The results obtained with this code are compared to experimental ones which are measured on a one-cylinder engine test bench. A good agreement is obtained between the experimental results and the numerical one. The model was improved by adding a transfer function for temperature evolution. The convergence time is then reduced as well as the global simulation time of the model.

关键词： gas dynamics compressible flow transfer function accuracy simulation time engine

THE dERIVATIVE PATCH INTERPOLATING RECOVERY TECHNIQUE FOR FINITE ELEMENT APPROXIMATIONS

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journal of Computational Mathematics 2004年第1期22卷 113-122页

作者： TieZhang Yan-pingLin R.j.Tait departmentofMathematics NortheasternUniversityShenyang110006China departmentofMathematics UniversityofAlbertaAlbertaCanadaT6G2G1

A derivative patch interpolating recovery technique is analyzed for the finite element approximation to the second order elliptic boundary value problems in two dimensional *** is shown that the convergence rate of the recovered gradient admits superc onvergence on the recovered subdomain, and is two order higher than the optimal global convergence rate (ultracovergence) at an internal node point when even order finite element spaces and local uniform meshes are used.

关键词： derivative recovery Finite element Ultraconvergence

MOdELING OF MICROSTRUCTURAL EVOLUTION IN MICROALLOYEd STEEL dURING HOT FORGING PROCESS

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Acta Metallurgica Sinica(English Letters) 2006年第4期19卷 279-286页

作者： j. Wang j. Chen Z. Zhao X.Y. Ruan National die ＆. Mold CAd Engineering Research Center Shanghai Jiaotong University Shanghai 200030 China

The microstractural evolution of microalloyed steel during hot forging process was investigated using physical simulation experiments. The dynamic recrystallized fraction was described by modifying Avrami＇s equation, the parameters of which were determined by single hit compression tests. double hit compression tests were performed to model the equation describing the static recrystallized fraction, and the obtained predicted values were in good agreement with the measured values. Austenitic grain growth was modeled as： dinc^5 = d0^5 ＋ 1.6 × 10^32t·exp （ -716870/RT ） using isothermal tests. Furthermore, an equation describing the dynamic recrystallized grain size was given as ddyn=3771·Z^-0.2. The models of microstructural evolution could be applied to the numerical simulation of hot forging.

关键词： microalloyed forging steel flow stress recrystallized fraction grain size

委内瑞拉用佩利多生产赤铁矿球团的半工业性试验

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烧结球团 1989年第5期14卷 31-36页

作者： A.j.Rodriguez d.Ionescu 宾晓燕委内瑞拉

1 前言当今,有机粘结剂在高炉及直接还原球团生产中的作用已引起了世界各地人们的极大兴趣。有机粘结剂可以降低球团最终脉石含量,提高球团质量,给钢铁生产带来效益。本文提出了用佩利多(Peridur)

关键词：赤铁矿球团粘接剂佩利多

Novel Strategies for Preparation and Characterization of Functional Polymer-metal Nanocomposites for Electrochemical Applications

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复旦学报（自然科学版） 2007年第5期46卷 630-631页

作者： d.N.Muraviev department of Chemistry Autonomous University of Barcelona08193 BellaterraBarcelona Spain

1 Introduction The synthesis and characterization of Metal NanoParticles (MNPs) has attracted great interest of scientists and technologists within the last years due their unique physical and chemical properties,which substantially differ from those of both bulk material and single *** properties provide various practical applications of MNPs including catalysis-and electrocatalysis-based processes,which occur in,for example,fuel cells of different types or in various sensing devices (***...

关键词： novel strategies polymer-metal nanocomposites

Peptic ulcer and childhood adversities experienced by working-aged people

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World journal of Gastroenterology 2009年第27期15卷 3405-3410页

作者： Markku PT Sumanen Markku j Koskenvuo Lauri H Sillanmki Kari j Mattila Kangasala Health Center and Medical School University of TampereFI 33014 Finland department of Public Health University of HelsinkiFI 00014 Finland department of General Practice University of Tampere Medical School and Hospital District of PirkanmaaFI 33014 Finland

AIM: To study the association between self-reported peptic ulcer and childhood ***: The Health and Social Support Study (HeS-Sup) population consisted of a stratif ied random sample drawn from the Finnish Population Register in four age groups: 20-24, 30-34, 40-44 and 50-54. The survey was carried out by postal questionnaire during 1998, with a response rate of 40.0%. A follow-up questionnaire was sent during 2003 to all those who responded to the f irst. Altogether 19 626 individuals returned the follow-up questionnaire; a response rate of 75.8%. The subjects were asked whether a doctor had told them that they have or have had peptic ulcer. The analyses covered those who responded aff irmatively to both the baseline and the follow-up enquiries (n = 718). Those not re-porting a peptic ulcer in either of the two questionnaires (n = 17 677) were taken as controls. The subjects were further requested (through six questions) to think about their childhood ***: The most common adversities mentioned were long-lasting financial difficulties in the family, serious conflicts in the family, and a family member seriously or chronically ill. All the adversities reported, except parental divorce, were more common among peptic ulcer patients than among controls (P values varied between d 0.003). Age- and sex-adjusted odds ratios (OR) of childhood adversities in the multivariate logistic analysis for self-reported pep-tic ulcer varied between 1.45 and 2.01. Adjusting for smoking, heavy drinking, stress and nonsteroidal anti-inflammatory drug use had no further influence (ORs between 1.22 and 1.73).CONCLUSION: Our findings suggest that childhood adversities maintain a connection with and have a predictive role in the development of peptic ulcer.

关键词： Peptic ulcer Working-aged Childhood adversities Stress factors Predictive role

Fidelity and Sacrifice: The Gender discourse of Traders in Pre- and Post-Opium War Canton

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Frontiers of History in China 2019年第4期14卷 473-507页

作者： john d.Wong Hong Kong Institute for the Humanities and Social Sciences The School of Modem Languages of CulturesThe University of Hong KongHong Kong SARChina

This article examines the discourse of two American couples in the China trade regarding fidelity and sacrifice during the period in which the spatial confines of the Canton system gave way to the intensified interactions of the Treaty Port *** the Opium War,when the Qing court had mandated that Western husbands conducting business in Canton live apart from their wives,marital tension was accentuated by the separation from absentee *** the subsequent Treaty Port era,enhanced spatial mobility of the couples did not assuage their ***,intensified cross-cultural encounters allowed them to project their feelings and expectations on the foreign other,'as racial categories developed and their imperial proclivities began to *** the Western women in contact with elite Chinese and other Western women only aggravated their agitation as they faced their Chinese counterparts,whom they readily construed as *** socio-political and spatial reconfigurations provided new dimensions to the discourse of fidelity and *** voices of the American couples recorded here are those of individuals,but the underlying anxiety they articulated represented the growing pains of more intimate Sino-Western encounters.

关键词： Sino-Western encounters China trade gender relations Canton/Guangzhou Opium War Treaty Port

SECONd-ORdER INTERACTION OF IRREGULAR WAVES WITH A TRUNCATEd COLUMN

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Acta Mechanica Sinica 1997年第2期13卷 130-142页

作者： j.B.Huang R.EatockTaylor department of Engineering Science University of OxfordParks RoadOxfordOX1 3PJUK

A complete semi-analytical solution is obtained for second-order diffraction of plane bichromatic waves by a fixed truncated circular *** fluid domain is divided into interior and exterior *** the exterior region,the second-order velocity potential is expressed in terms of‘locked-wave’and‘free-wave’ components,both are solved using Fourier and eigenfunction *** re- sulting‘locked wave’potential is expressed by one-dimensional Green's integrals with oscillating *** order to increase computational efficiency,the far-field part of the integrals are carried out *** in both regions are matched on the interface by the potential and its normal derivative continuity *** on the present approach,the sum-and difference-frequency potentials are efficiently evaluated and are used to generate the quadratic transfer functions which correlates the incident wave spectrum with second-order forcing spectrum on the *** sum-frequency QTFs for a TLP column are present,which are compared for some frequency pairs with those from a fully numerical *** agreement has been *** spectra for a case study TLP column,generated using the semi-analytical solution are *** given are the results for nonlinear wave field around the column.

关键词： marine hydrodynamics nonlinear wave force wave-structure interaction second-order wave diffraction