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Effect of a force-free end on the mechanical property of a biopolymer--A path integral approach

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Chinese Physics B 2016年第8期25卷 468-473页

作者：周子聪 Bla Joós Department of Physics Tamkang University Ottawa carleton Institute for Physics University of Ottawa Campus

We study the effect of a force-free end on the mechanical property of a stretched *** system can be divided into two *** first part consists of the segment counted from the fixed point（i.e.,the origin） to the forced point in the biopolymer,with arclength L_*** second part consists of the segment counted from the forced point to the force-free end with arclength △*** apply the path integral technique to find the relationship between these two *** finite temperature and without any constraint at the end,we show exactly that if we focus on the quantities related to the first part,then we can ignore the second part *** Carlo simulation confirms this *** contrast,the effect for the quantities related to the second part is dependent on what we want to observe.A force-free end has little effect on the relative extension,but it affects seriously the value of the end-to-end distance if △L is comparable to L_f.

关键词： statistical physics path integral biopolymers mechanical property

Synthesis of a Poly(amide-imide)from 5,6-Diphenyl-1-chloroformyl3,4-benzenedicarboxylic Anhydride and Bis (4-aminophenyl)ether

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Chinese Chemical Letters 1999年第5期10卷 371-372页

作者： Xi Gao JIAN Lin CHENG Hai Bin ZtlEN Zhi Yuan WANG(Department of Polymer Science & Materials. Dalian university of Technology. Dalian 116012Department of Chemistry. carleton university. Ottawa. Canada) Dalian Univ Technol Dept Polymer Sci & Mat Dalian 116012 Peoples R China carleton Univ Dept Chem Ottawa ON K1S 5B6 Canada

A novel poly (amide-imide) was prepared from a novel monomer: 5,6-diphenyl-chloroformyl-3,4-benzenedicarboxylic anhydride and bis (4-aminophenyl) ether. The polymer was characterized by FTIR. (HNMR)-H-1. DSC and TGA.

关键词： poly (amide-imide) 5,6-diphenyl-chloroformyl-3,4-benzenedicarboxylic anhydride

Resource Allocation and User Association for HTTP Adaptive Streaming in Heterogeneous Cellular Networks with Small Cells

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China Communications 2016年第9期13卷 1-11页

作者： Jiang Liu State Key Laboratory of Networking and Switching Technology Beijing University of Post and TelecommunicationsBeijing 100876China Department of Systems and Computer Engineering Carleton UniversityOttawaONCanada Beijing Advanced Innovation Center for Future Internet Technology Beijing 100124China

Video streaming,especially hypertext transfer protocol based(HTTP) adaptive streaming(HAS) of video,has been expected to be a dominant application over mobile networks in the near future,which brings huge challenge for the mobile *** some works have been done for video streaming delivery in heterogeneous cellular networks,most of them focus on the video streaming scheduling or the caching strategy *** problem of joint user association and rate allocation to maximize the system utility while satisfying the requirement of the quality of experience of users is largely *** this paper,the problem of joint user association and rate allocation for HTTP adaptive streaming in heterogeneous cellular networks is studied,we model the optimization problem as a mixed integer programming *** to reduce the computational complexity,an optimal rate allocation using the Lagrangian dual method under the assumption of knowing user association for BSs is first *** we use the many-to-one matching model to analyze the user association problem,and the joint user association and rate allocation based on the distributed greedy matching algorithm is ***,extensive simulation results are illustrated to demonstrate the performance of the proposed scheme.

关键词： heterogeneous cellular networks user association rate allocation http adaptive streaming matching algorithm

AGING PROPERTIES OF THE LIFETIME IN SIMPLE ADDITIVE DEGRADATION MODELS

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Journal of Systems Science & Complexity 2011年第4期24卷 753-760页

作者： Xiaohu LI Rongfang YAN Yiqiang ZHAO School of Mathematical Science Xiamen University Xiamen 361005 China. College of Mathematics and Information Beienee Northwest Normal University Lanzhou 730050 China. Schoolof Mathematics and Statistics Carleton University Ottawa Ontario KIS 5B6 Canada.

This paper deals with the simple additive degradation models with single random effect. The authors further study the link between the aging property of the implied lifetime and that of the random variation. It is found that both the aging property of the random variation and the analytical behavior of the mean degradation path influence the aging behavior of the implied lifetime.

关键词： decreasing reversed hazard rate (DRHR) failure rate increasing failure rate (IFR) increasing failure rate in average (IFRA) new better than used (NBU) star-shaped super-additivity.

CREEP OF A POLYCRYSTALLINE NEAR γ-TiAl Alloy WITH A LAMELLAR MICROSTRUCTURE

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 565-570页

作者： WR. Chen J.Triantafillou J. Beddoes and L. Zhao(Dept. of Mech. & Aero. Eng.,carleton university, Ottawa,Canada Structures, Materials & Propulsion Laboratory,National Research Council, Ottawa, Canada ) carleton Univ Ottawa Canada

Creep of a polycrystalline near γ-TiAl alloy in two fully lamellar conditions is presented. A lamellar structure with fine interface spacing and planar grain boundaries provides improved creep resistance. The lamellar structure with wide interface spacing and interlocked grain boundaries has <1/2 the creep life, five times the minimum strain rate and greater tertiary *** strain is accommodated by dislocation motion in soft grains, but the strain rate is controlled by hard grains. The resistance to fracture is controlled by the grain boundary morphology, with planar boundaries causing intergranular *** maximize the creep resistance of near γ-TiAl with a lamellar microstructure requires narrow lamellar interface spacing and interlocked lamellae along grain boundaries.

关键词： creep,γ-TiAl titanium aluminides lamellar structure

DYNAMIC FRICTION:Ⅰ.EXPERIMENTAL OBSERVATIONS OF ROCK FRICTION

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Geotectonica et Metallogenia 1998年第Z1期22卷 28-41页

作者： S. Z. Chen(Ottawa-carleton Geosczence Centre and Dept. of Earth Sciences, carleton university,Ottawa, ON K1S5B6, Canada, email: szchen ccs. carleton. ca )

Dynamic friction is a critical process of crustal earthquake ruptures. Recent experimenta1 and theoretica1 progress in rock friction have demonstrated that most continental earthquakes are associated with stick-slip in the brittle field of the crust and that only dynamic instability with fast slip is related to seismicity. Dynamic stability will be influenced by frictional parameters a-b, a, stiffness K, characteristic displacement L, slip rate history (velocity weakening), normal stress history (pressure strengthening), and temperature, which is described by the frictional constitutive laws. Velocity-weakening (a-b<0) can cause dynamic instability if the medium stiffness is below the critical stiffness (X/Kc<1), while velocity-strengthening enhances the frictional *** most recent experimental evidence of rock friction will be systematically reviewed in this paper.

关键词： Dynamic friction earthquake frictional parameter experimental observation

STRUCTURE OF THE TIBETAN LITHOSPHERE FROM GEOPHYSICAL EVIDENCE

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Geotectonica et Metallogenia 1997年第Z2期21卷 11-32页

作者： S. Z. Chen and G. Ranalli(Ottawa-carleton Geoscience Centre and Department of Earth Sciences,carleton university, Ottawa, ONKIS 5B6, Canada)

The Tibetan lithosphere plays an important role in global geodynamics, Geophysical evidence from gravity, geoidal, seismic, geothermal, and magnetotelluric (MT) observations provides important insights on the structure of the lithosphere, with implications for rheology and *** largest amplitudes of 1°× 1° negative Bouguer anomdlies in Tibet appear to renect a relatively soft, multilayered, low density lithosphere beneath the plateau. A density-contrast interface (possible base of the lithosphere), obtained by gravity inversion, shows a maximum depth of about l35 km near the ITS (Yaluzangbu suture), decreasing toward both southern and northern borders, with steeper slope in southern Tibet than in north central Tibet. The Himalayan collision zone corresponds to a north-dipping slope of Indian lithosphere plunging below the Higher Himalayas at the maximum dip angle of 36° Lateral variations between southern and north central Tibet are evidenced from both geoidal, using spherical harmonic differences of degrees 18O and 20,and seismic analyses using attenuation, anisotropy, and velocities including the Vnp *** wave-like pzttern of positive and negative lateral changes of crustal density suggests a convergent (compressive) zone in the Himalayas and southern Tibet and a divergent (extensional)zone in north central Tibet, respectively. The lowest Pn velocity of 7.78~7. 83 km s-1 and low S wave velocities in the upper mantle are observed in north central Tibet, whereas high P-and. Swave velocities in the upper mantle, including high Vpn, are found in southern Tibet. Geothermal modeling reveals an heterogeneous thermal structure: southern Tibet has a relatively cold mantle,while northern Tibet has a relatively hbt mantle. The differences between southern and northern Tibet with respect to many geophysical observations should be taken into account for updating and improving thermorheological models of the lithosphere. The strctural features of the Tibeta

关键词： Tibetan lithosphere Himalayan collision zone geophysical evidene

Detonation nanodiamond and its applications:A case from China

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金刚石与磨料磨具工程 2008年第S1期28卷 44-49页

作者： Annie Hui~1,Wang Guangzu~2 (1.carleton university,Canada KAL Superabrasives Co.,Ltd,Canada) (2.Zhengzhou Research Institute for Abrasives and Grinding,Zhengzhou 450013,China)

Nanodiamond is a new material which has the dual properties of diamond and *** dual properties have contributed to its wide applications in many industrial *** paper briefly reviews the development of nanodiamond,describes its synthesis technology under dynamic high-temperature and high-pressure conditions,and introduces its properties as well as *** are made about nanodiamond’ s potentially successful applications in the future.

关键词： Explosion Detonation Nanodiamond

ENUMERATING CORRELATION-IMMUNE BOOLEAN FUNCTIONS OF ORDER ONE

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Journal of Electronics(China) 1998年第1期15卷 50-57页

作者： Tian Haijian Yang Yixian(Dept. of Inform. Eng., Beijing Univ. of Posts and Telecomm., Beijing 100088)Wang Jianyu( carleton university of Canada) Dept. of Inform. Eng. Beijing Univ. of Posts and Telecomm. Beijing carleton university of Canada Canada

A large class of linear structural functions(LSF) satisfying the condition of correlational immunity of order one are constructed by studying the linear structural Boolean functions. With these new founded functions, the known enumeration bounds of correlation-immune functions of order one are greatly improved. In fact, the best, up to now, lower bound is found.

关键词： Boolean function Stream ciphers Correlation-immune function