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Biomedical and Environmental Sciences 2010年第4期23卷 287-292页

作者： WEN-JUAN MA JUN-JIE WANG KATHLEEN-H. REILLY AI-MEI BI GUO-WEI DING KUMI SMITH NING WANG School of Public Health Peking Union Medical College Tsinghua University Beijing 100730 China National Center for AIDS/STD Control and Prevention Beijing 102206 China Tulane University Health Sciences Center School of Public Health and Tropical Medicine New Orleans LA USA Kaiyuan Center for Disease Control and Prevention Kaiyuan 661600 Yunnan China University of North Carolina at Chapel Hill Chapel Hill NC USA

Objective To estimate the probability of unprotected heterosexual vaginal transmission of HIV-1 from clients to Female Sex Workers （FSWs） in Kaiyuan County, Yunnan province, China, and analyze factors which impact the transmission probability. Methods An open cohort research of FSWs in Kaiyuan was created from surveys conducted in April 2008, October 2008, and April 2009. Two cross-sectional surveys of local clients were also carried out in May 2008 and November 2008. A model was developed to estimate the probability of unprotected heterosexual vaginal transmission of HIV-1 from clients to FSWs. Results The transmission probability from clients to FSWs was estimated as 0.0023 [95% CI 0.0014-0.0032] per unprotected heterosexual act. Conclusion The transmission probability among this group engaging in commercial sex in Yunnan province differs from that found in studies from other countries, and future studies should estimate the influence factors of HIV-1 transmission probability, such as stage of HIV infection, co-morbid sexually transmitted infections （STIs）.

关键词： transmission probability HIV/AIDS Model FSW Clients

Transport properties through double-magnetic-barrier structures in graphene

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Chinese Physics B 2011年第7期20卷 405-409页

作者：王素新李志文刘建军李玉现 Department of Physics Hebei Normal College for Nationalities Hebei Advanced Film Laboratory College of Physics Hebei Normal University

We study electrons tunneling through a double-magnetic-barrier structure on the surface of monolayer graphene. The transmission probability and the conductance are calculated by using the transfer matrix method. The results show that the normal incident transmission probability is blocked by the magnetic vector potential and the Klein tunneling region depends strongly on the direction of the incidence electron. The transmission probability and the conductance can be modulated by changing structural parameters of the barrier, such as width and height, offering a possibility to control electron beams on graphene.

关键词： transmission probability conductance double-magnetic-barrier graphene

Quantum transport signatures of non-trivial topological edge states in a ring-shaped Su–Schrieffer–Heeger double-chain system

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Chinese Physics B 2022年第2期31卷 558-565页

作者： Cheng-Zhi Ye Lan-Yun Zhang Hai-Bin Xue School of Physics and Electronic Engineering Linyi UniversityLinyi 276005China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

In the ring-shaped Su–Schrieffer–Heeger(SSH)double-chain,the quantum interference between the two different electron tunneling paths of the upper and lower chains has an important influence on the electron transport properties of non-trivial topological edge ***,we have studied the electron transport signatures of non-trivial topological edge states in a ring-shaped SSH double-chain system based on the wave-guide theory and transfer-matrix *** the ringshaped SSH double-chain with the upper chain being different from the lower one,it is demonstrated that the electron transmission probability displays the four and two resonance peaks associated with the non-trivial topological edge states in the weak and strong coupling regimes,*** in the case of the upper chain being the same as the lower one,the two transmission resonance peaks associated with the non-trivial topological edge states in the weak coupling regime are only found,and that in the strong coupling regime disappear that originated from the destructive interference between the two different electron tunneling paths of the upper and lower ***,the variation of the number of transmission resonance peaks associated with the non-trivial topological edge states in the weak and strong coupling regimes suggests that an alternative scheme for detecting non-trivial topological edge states in the ring-shaped SSH doublechain system.

关键词： ring-shaped Su-Schrieffer-Heeger double-chain non-trivial topological edge states transmission probability

Influence of time-periodic potentials on electronic transport in double-well structure

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Chinese Physics B 2010年第5期19卷 488-493页

作者：李春雷徐燕 College of Elementary Educational Capital Normal University

Within the framework of the Floquet theorem, we have investigated single-electron photon-assisted tunneling in a double-well system using the transfer matrix technique. The transmission probability displays satellite peaks on both sides of the main resonance peaks and these satellite peaks originate from emission or absorption photons. The single-electron resonance tunneling can be controlled through changing the applied harmonically potential positions, such as driven potential in wells, in barriers, or in whole double-well systems. This advantage should be useful in the optimization of the parameters of a transmission device.

关键词： photon-assisted tunneling transmission probability quantum well

A novel MAC mechanism to resolve 802.11 performance anomaly

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1573-1583页

作者： CHENG Yan-hong LI Zhi-shu XING Jian-chuan ZHU Li School of Computer Science Sichuan University Chengdu 610065 China

In the 802.11b networks, the guarantee of an equal long-run channel access probability causes performance anomaly in a multi-rate wireless cell. Much interest has been involved in this issue and many effective mechanisms have been proposed. The usual MAC layer solutions include the initial contention window adaptation, the maximum transfer unit size adaptation and the packet bursting. In this paper, we propose a novel approach which introduces a new parameter called the transmission prob- ability pt to the legacy protocol. By adjusting pt according to the transmission rate, the proposed scheme can solve the performance anomaly problem cleanly. Throughput analysis and performance evaluation show that our scheme achieves significant im- provement in the aggregate throughput and the fairness.

关键词： IEEE 802.11 WLAN transmission probability Performance anomaly

Spin-Polarized Transport through a Quantum Dot Coupled to Ferromagnetic Leads and a Mesoscopic Ring

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Communications in Theoretical Physics 2010年第2期53卷 355-360页

作者：黄睿吴绍全 College of Sciences Southwest Petroleum University College of Physics and Electronic Engineering Sichuan Normal University

Using an equation of motion technique, we investigate the spin-polarized transport through a quantum dot coupled to ferromagnetic leads and a mesoseopie ring by the Anderson Hamiltonian. We analyze the transmission probability of this system in both the equilibrium and nonequilibrium cases, and our results reveal that the transport properties show some noticeable characteristics depending upon the spin-polarized strength p, the magnetic flux Ф and the number of lattice sites NR in the mesoseopic ring. These effects might have some potential applications in spintronics.

关键词： Kondo effect spin-polarized transport transmission probability

Conductance of three-terminal molecular bridge based on tight-binding theory

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Chinese Physics B 2005年第5期14卷 1011-1014页

作者：王利光李勇郁鼎文 KatsunoriTagami MasaruTsukada CollegeofScience SouthernYangtzeUniversityWuxi214122China DepartmentofPrecisionInstrument TsinghuaUniversityBeijing100084China DepartmentofPhysics GraduateSchoolofScienceUniversityofTokyoTokyo113-0033Japan

The quantum transmission characteristic of three-benzene ring nano-molecular bridge is investigated theoretically by using Green's function approach based on tight-binding theory with only aπ orbital per carbon atom at the *** transmission probabilities that electrons transport through the molecular bridge from one terminal to the other two terminals are obtained. The electronic current distributions inside the molecular bridge are calculated and shown in graphical analogy by the current density method based on Fisher-Lee formula at the energy points E=±0.42,±1.06 and ±1.5, respectively, where the transmission spectra appear peaks. We find that the transmission spectra are related to the incident electronic energy and the molecular levels strongly, and the current distributions agree well with Kirchhoff quantum current momentum conservation law.

关键词： molecular bridge transmission probability molecular device

Lifetime of resonant state in a spherical quantum dot

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Chinese Physics B 2007年第1期16卷 67-71页

作者：李春雷肖景林 College of Physics and Electromechanics Inner Mongolia National University Tongliao 028043 China

This paper calculates the lifetime of resonant state and transmission probability of a single electron tunnelling in a spherical quantum dot （SQD） structure by using the transfer matrix technique. In the SQD, the electron is confined both transversally and longitudinally, the motion in the transverse and longitudinal directions is separated by using the adiabatic approximation theory. Meanwhile, the energy levels of the former are considered as the effective confining potential. The numerical calculations are carried out for the SQD consisting of GaAs/InAs material. The obtained results show that the bigger radius of the quantum dot not only leads significantly to the shifts of resonant peaks toward the low-energy region, but also causes the lengthening of the lifetime of resonant state. The lifetime of resonant state can be calculated from the uncertainty principle between the energy half width and lifetime.

关键词： spherical quantum dot lifetime of resonant state transmission probability