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The quantum Kirchhoff equation and quantum current and energy spectrum of a homogeneous mesoscopic dissipation transmission line 被引量:2
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作者 崔元顺 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期3093-3096,共4页
On the basis of quantization of charge, the loop equations of quantum circuits are investigated by using the Helsenberg motion equation for a mesoscopic dissipation transmission line. On the supposition that the syste... On the basis of quantization of charge, the loop equations of quantum circuits are investigated by using the Helsenberg motion equation for a mesoscopic dissipation transmission line. On the supposition that the system has a symmetry under translation in charge space, the quantum current and the quantum energy spectrum in the mesoscopic transmission llne are given by solving their eigenvalue equations. Results show that the quantum current and the quantum energy spectrum are not only related to the parameters of the transmission llne, but also dependent on the quantized character of the charge obviously. 展开更多
关键词 mesoscopic dissipation transmission line quantum Kirchhoff's equation quantum current quantum energy spectrum
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Design of Time-Resolved Shifted Dual Transmission Grating Spectrometer for the X-Ray Spectrum Diagnostics 被引量:1
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作者 王保清 易涛 +6 位作者 王传珂 朱效立 李廷帅 李晋 刘慎业 江少恩 丁永坤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第7期781-785,共5页
A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which... A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which has two sub transmission gratings with different line densities, of 2000 lines/mm and 5000 lines/mm. The axes of the two sub transmission gratings in SDTG are horizontally and vertically shifted a certain distance to measure a broad range of 0.1-5 keV time-resolved X-ray spectra. The SDTG has been calibrated with a soft X-ray beam of the synchrotron radiation facility and its diffraction efficiency is also measured. The designed SDTGS can take full use of the space on a record panel and improve the precision for measuring spatial and temporal spectrum simultaneously. It will be a promising application for accurate diagnosis of the soft X-ray spectrum in inertial confinement fusion. 展开更多
关键词 shifted dual transmission grating spectrometer GRATING X-ray spectra diag-nosis of the soft X-ray spectrum
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Irregular and regular LDPC codes with high spectrum efficiency modulation in image transmission over fading channel 被引量:1
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作者 MaPiming YuanDongfeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期26-30,共5页
If the degree distribution is chosen carefully, the irregular low-density parity-check (LDPC) codes can outperform the regular ones. An image transmission system is proposed by combining regular and irregular LDPC cod... If the degree distribution is chosen carefully, the irregular low-density parity-check (LDPC) codes can outperform the regular ones. An image transmission system is proposed by combining regular and irregular LDPC codes with 16QAM/64QAM modulation to improve both efficiency and reliability. Simulaton results show that LDPC codes are good coding schemes over fading channel in image communication with lower system complexity. More over, irregular codes can obtain a code gain of about 0.7 dB compared with regular ones when BER is 10 -4. So the irregular LDPC codes are more suitable for image transmission than the regular codes. 展开更多
关键词 irregular low-density parity-check (LDPC) codes degree distribution image transmission high spectrum efficiency modulation.
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Asymptotic Analysis of Transmission Capacities for Overlaid Spread-Spectrum Wireless Networks 被引量:1
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作者 Huarui Wu Di Li Changchuan Yin 《China Communications》 SCIE CSCD 2010年第3期81-90,共10页
We study the transmission capacities of two coexisting spread-spectrum wireless networks (a primary network vs. a secondary network) that operate in the same geographic region and share the same spectrum. We defi ne t... We study the transmission capacities of two coexisting spread-spectrum wireless networks (a primary network vs. a secondary network) that operate in the same geographic region and share the same spectrum. We defi ne transmission capacity as the product among the density of transmissions, the transmission rate, and the successful transmission probability. The primary (PR) network has a higher priority to access the spectrum without particular considerations for the secondary (SR) network, while the SR network limits its interference to the PR network by carefully controlling the density ofits transmitters. Considering two types of spread-spectrum transmission schemes (FH-CDMA and DS-CDMA) and the channel inversion power control mechanism, we quantify the transmission capacities for these two networks based on asymptotic analysis. Our results show that if the PR network permits a small increase ofits outage probability, the sum transmission capacities of the two networks (i.e., the overall spectrumefficiency per unit area) will be boosted significantly over that of a single network. 展开更多
关键词 transmission capacity ad hoc network spread spectrum stochastic geometry
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UV-Vis Spectrum and the Third-order Nonlinear Optical Properties of the Chiral Camphorderived β-diketonate Platinum Complexes 被引量:1
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作者 龚雪 卫航 +1 位作者 骆开均 李权 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第3期422-428,共7页
UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing g... UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down. 展开更多
关键词 camphor-derived β-diketonate platinum complexes the third-order nonlinear optical properties uv-vis absorption spectrum density functional theory
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Space-Resolved Spectrum Diagnose by Soft X-Ray Transmission Grating Spectrometer
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作者 尚万里 赵阳 +2 位作者 熊刚 杨家敏 朱托 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第1期36-39,共4页
A space-resolving transmission grating spectrometer is established on the "Shenguang-III" prototype laser facility and an iterative procedure for unfolding the X-ray spectrum with spatial resolution is described. Th... A space-resolving transmission grating spectrometer is established on the "Shenguang-III" prototype laser facility and an iterative procedure for unfolding the X-ray spectrum with spatial resolution is described. The diagnostics is applied to measure the X-ray spectrum from laser-entered gold target and the typical space-resolved spectrum is provided. The relative standard uncertainty of the X-ray spectrum from the laser-generated plasma is also determined. 展开更多
关键词 transmission grating spectrometer numerical simulation spectrum diagnose
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MULTI-CHANNEL TRANSMISSION STRATEGY FOR DYNAMIC SPECTRUM ACCESS
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作者 Wu Yingxiao Yang Zhen 《Journal of Electronics(China)》 2010年第3期345-352,共8页
Cognitive radio is a promising technology that deals with the scarcity of radio spectrum. In this paper, we propose a new multi-channel transmission strategy for dynamic spectrum access in cognitive radio network. Sta... Cognitive radio is a promising technology that deals with the scarcity of radio spectrum. In this paper, we propose a new multi-channel transmission strategy for dynamic spectrum access in cognitive radio network. Starting with the model of spectrum activities, we present the multi-channel transmission strategy which has primary user's protection mechanism to improve the spectrum efficiency and study its performance under perfect and imperfect sensing. Numerical example results reveal that the performance of the proposed strategy has the superiority with respect to capacity performance of cognitive users and the protection of primary users. 展开更多
关键词 transmission strategy Dynamic spectrum access Multiple channels
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Dynamic Spectrum Control-Assisted Secure and Efficient Transmission Scheme in Heterogeneous Cellular Networks
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作者 Chenxi Li Lei Guan +3 位作者 Huaqing Wu Nan Cheng Zan Li Xuemin(Sherman)Shen 《Engineering》 SCIE EI CAS 2022年第10期220-231,共12页
Heterogeneous cellular networks(HCNs)are envisioned as a promising architecture to provide seamless wireless coverage and increase network capacity.However,the densified multi-tier network architecture introduces exce... Heterogeneous cellular networks(HCNs)are envisioned as a promising architecture to provide seamless wireless coverage and increase network capacity.However,the densified multi-tier network architecture introduces excessive intra-and cross-tier interference and makes HCNs vulnerable to eavesdropping attacks.In this article,a dynamic spectrum control(DSC)-assisted transmission scheme is proposed for HCNs to strengthen network security and increase the network capacity.Specifically,the proposed DSC-assisted transmission scheme leverages the idea of block cryptography to generate sequence families,which represent the transmission decisions,by performing iterative and orthogonal sequence transformations.Based on the sequence families,multiple users can dynamically occupy different frequency slots for data transmission simultaneously.In addition,the collision probability of the data transmission is analyzed,which results in closed-form expressions of the reliable transmission probability and the secrecy probability.Then,the upper and lower bounds of network capacity are further derived with given requirements on the reliable and secure transmission probabilities.Simulation results demonstrate that the proposed DSC-assisted scheme can outperform the benchmark scheme in terms of security performance.Finally,the impacts of key factors in the proposed DSC-assisted scheme on the network capacity and security are evaluated and discussed. 展开更多
关键词 Heterogeneous cellular networks Dynamic spectrum control transmission security Efficient data transmission
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Impact of the Opto-Geometric Parameters on the Band Diagram and Transmission and Reflection Spectrum of the Bragg Structure
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作者 Iman Ouahab Leila Dekkiche Rafah Naoum 《Optics and Photonics Journal》 2013年第2期184-189,共6页
Knowledge of the band gap and transmission and reflection spectrum of a photonic crystal is essential elements for their design. A graphical interface that quickly determines the banding pattern and spectrum based on ... Knowledge of the band gap and transmission and reflection spectrum of a photonic crystal is essential elements for their design. A graphical interface that quickly determines the banding pattern and spectrum based on the Plane Wave Method (PWM) and coupled modes method (CMM) respectively is created. It is used to explore the behavior of a Bragg structure with the ability to easily vary the important parameters such as refractive indices, number and thickness of layers. 展开更多
关键词 BRAGG STRUCTURE PWM CMM GRAPHIC User Interface PHOTONIC Band Gap spectrum of transmission and Reflection
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Design of interference-imaging spectrum data transmission Card Based on PCI Bus
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作者 Ma, Dongmei Gao,Wei Wang,Xinfeng 《微计算机信息》 北大核心 2005年第08Z期122-123,共2页
Take the interference- imaging spectrometer for exam-ple, the paper analyses the characters of the spectrum- formingsignals and their timing sequence. Then inspects the key tech-nology in the interference - imaging sp... Take the interference- imaging spectrometer for exam-ple, the paper analyses the characters of the spectrum- formingsignals and their timing sequence. Then inspects the key tech-nology in the interference - imaging spectrum data transmissionsystem, and indicates a design for the system- - which is basedon computer PCI bus with CPLD technique imbedded. The sys-tem’ s circuitry and function are also presented. 展开更多
关键词 光谱 干涉现象 数据传输 时间序列
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Ion irradiation-induced structure damage to botanic samples using the ion transmission energy spectrum
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作者 WANGSi-xue WANGYu-Gang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2002年第1期31-36,共6页
In order to study the mechanism of irradiation-induced damage ofbotanic samples caused by low energy heavy ions, transmission energy spectrum mea-surement was performed. Kidney bean slice samples 100μm in thickness w... In order to study the mechanism of irradiation-induced damage ofbotanic samples caused by low energy heavy ions, transmission energy spectrum mea-surement was performed. Kidney bean slice samples 100μm in thickness were irradi-ated by 50 kev N+ ions. The irradiation beam current density was about 30μA/cm2,and the irradiation ion doses were 1×1015, 1×1016, 3×1016 and 1×1017 ions@cm-2,respectively. A target set up that could greatly reduce the incident ion current densitywas designed to achieve the damage-free measurement. The 3.2 MeV H+ transmittedion energy spectrum measurement was carried out before and after the irradiation.From the transmission ion energy spectrum, it was found that the kidney bean sliceitself was structurally inhomogeneous compared with the PET films (C10HsO4). Ourresults indicated that the average mass thickness changed little when the N+ iondose was below 3×1016 ions.cm-2, but changed obviously whcn ion dose was beyond3×1016 ions.cm-2. 展开更多
关键词 重离子 辐照损失 离子传输能谱
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Analysis of vibration and frequency transmission of high speed EMU with flexible model 被引量:5
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作者 Zun-Song Ren Guang Yang +1 位作者 Shan-Shan Wang Shou-Guang Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期876-883,共8页
When the operation speed of the high-speed train increases and the weight of the carbody becomes lighter,not only does the sensitivity of the wheel/rail contact get higher,but also the vibration frequency range of the... When the operation speed of the high-speed train increases and the weight of the carbody becomes lighter,not only does the sensitivity of the wheel/rail contact get higher,but also the vibration frequency range of the vehicle system gets enlarged and more frequencies are transmitted from the wheelset to the carbody.It is important to investigate the vibration characteristics and the dynamic frequency transmission from the wheel/rail interface to the carbody of the high-speed electric multi-uint(EMU).An elastic highspeed vehicle dynamics model is established in which the carbody,bogieframes,and wheelsets are all dealt with as flexible body.A rigid high-speed vehicle dynamics model is set up to compare with the simulation results of the elastic model.In the rigid vehicle model,the carbody,bogieframes and wheelsets are treated as rigid component while the suspension and structure parameters are the same as used in the elastic model.The dynamic characteristic of the elastic high speed vehicle is investigated in time and frequency domains and the di ff erence of the acceleration,frequency distribution and transmission of the two types of models are presented.The results show that the spectrum power density of the vehicle decreases from the wheelset to the carbody and the acceleration transmission ratio is approximately from 1%to 10%for each suspension system.The frequency of the wheelset rotation is evident in the vibration of the flexible model and is transmitted from the wheelset to the bogieframe and to thecarbody.The results of the flexible model are more reasonable than that of the rigid model.A field test data of the high speed train are presented to verify the simulation results.It shows that the simulation results are coincident with the field test data. 展开更多
关键词 High-speed EMU Vibration transmission Flexible model ACCELERATION Power spectrum density
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A new framework for evaluating along-wind responses of a transmission tower 被引量:3
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作者 Liu Guohuan and Li Hongnan School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116023, China PhD Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期87-93,共7页
In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized ... In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized force spectrum (GFS) model of the transmission tower is deduced; (2) an analytical model that includes the contributions of the higher modes is further derived as a rational algebraic formula to estimate the structural displacement response; and (3) a new approach, applying load with displacement (ALD) instead of force, to solve the internal force of transmission tower is given. Unlike conventional methods, the ALD method can avoid calculating equivalent static wind loads (ESWLs). Finally, a transmission tower structure is used as a numerical example to verify the feasibility and accuracy of the ALD method. 展开更多
关键词 along-wind-induced dynamic responses transmission tower generalized force spectrum equivalent static wind loads
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Modelling Wave Transmission and Overtopping Based on Energy Balance Equation 被引量:2
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作者 JI Qiaoling DONG Sheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1033-1043,共11页
Wave transmission and overtopping around nearshore breakwaters can have significant influence on the transmitted wave parameters,which affects wave conditions and sediment transportation and becomes the focus of desig... Wave transmission and overtopping around nearshore breakwaters can have significant influence on the transmitted wave parameters,which affects wave conditions and sediment transportation and becomes the focus of design in engineering.The objective of this paper is to present a simplified model to estimate these important wave parameters.This paper describes the incorporation of wave transmission and overtopping module into a wave model for multi-directional random wave transformation based on energy balance equation with the consideration of wave shoaling,refraction,diffraction,reflection and breaking.Wen's frequency spectrum and non-linear dispersion relation are also included in this model.The influence of wave parameters of transmitted waves through a smooth submerged breakwater has been considered in this model with an improved description of the transmitted wave spectrum of van der Meer et al.(2000) by Carevic et al.(2013).This improved wave model has been validated through available laboratory experiments.Then the verified model is applied to investigate the effect of wave transmission and overtopping on wave heights behind low-crested breakwaters in a project for nearshore area.Numerical calculations are carried out with and without consideration of the wave transmission and overtopping,and comparison of them indicates that there is a considerable difference in wave height and thus it is important to include wave transmission and overtopping in modelling nearshore wave field with the presence of low-crested breakwaters.Therefore,this model can provide a general estimate of the desired wave field parameters,which is adequate for engineers at the preliminary design stage of low-crested breakwaters. 展开更多
关键词 random wave transformation energy balance equation numerical modelling Wen's spectrum DIFFRACTION transmission OVERTOPPING
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Spectral analysis of the UFBG-based acousto optical modulator in V–I transmission matrix formalism 被引量:1
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作者 吴良英 裴丽 +3 位作者 刘超 王一群 翁思俊 王建帅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期247-252,共6页
In this study, the V-I transmission matrix formalism (V-I method) is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating (FBG)-based acousto--opfic modulators (UFBG-AOM). The simu... In this study, the V-I transmission matrix formalism (V-I method) is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating (FBG)-based acousto--opfic modulators (UFBG-AOM). The simulation results demon- strate that both the amplitude of the acoustically induced strain and the frequency of the acoustic wave (AW) have an effect on the spectrum. Additionally, the wavelength spacing between the primary reflectivity peak and the secondary reflectivity peak is proportional to the acoustic frequency with the ratio 0.1425 nm/MHz. Meanwhile, we compare the amount of calculation. For the FBG whose period is M, the calculation of the V-I method is 4 × (2M-l) in addition/subtraction, 8 × (2M - 1) in multiply/division and 2M in exponent arithmetic, which is almost a quarter of the multi-film method and transfer matrix (TM) method. The detailed analysis indicates that, compared with the conventional multi-film method and transfer matrix (TM) method, the V-I method is faster and less complex. 展开更多
关键词 uniform fiber bragg grating (UFBG) acousto-optic modulator (AOM) V-I transmission matrixformalism spectrum
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A novel X-ray tube spectra reconstruction method based on transmission measurements 被引量:2
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作者 Jing Cao Chun-Yu Jiang +2 位作者 Yan-Feng Zhao Qing-Wei Yang Ze-Jie Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第2期73-78,共6页
A novel X-ray tube spectrum reconstruction method has been proposed based on transmission measurements. Aluminum bars of varying lengths attenuate the X-rays to different levels. The detectors are of lutetium yttrium ... A novel X-ray tube spectrum reconstruction method has been proposed based on transmission measurements. Aluminum bars of varying lengths attenuate the X-rays to different levels. The detectors are of lutetium yttrium oxyorthosilicate scintillator and silicon photomultiplier. With the detected X-ray intensities, the X-ray spectrum is unfolded using the least square method. The detectors, aluminum bars, and collimating apertures are integrated in a detection module made of lead. Its response to X-ray is calculated by Monte Carlo codes Geant4. Due to the high photon flux, the detectors work in current mode.The electronics system, consisting of 24-bit high-precision ADCs with 144 KSPS sampling rate and field programmable gate array, makes the data acquisition process effective and precise. Measurements on a 70-k Vp tungsten anode X-ray were taken to verify the method. The unfolded spectrum agrees well with the simulated spectrum,demonstrating that the method is reliable and practical. 展开更多
关键词 X射线管 重建方法 传输测量 光谱 现场可编程门阵列 透射 GEANT4 蒙特卡罗程序
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Evolution Handoff Strategy for Real-Time Video Transmission over Practical Cognitive Radio Networks 被引量:1
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作者 LIU Fa MA Yongkui +1 位作者 ZHAO Honglin DING Kai 《China Communications》 SCIE CSCD 2015年第2期141-154,共14页
The transmission delay of realtime video packet mainly depends on the sensing time delay(short-term factor) and the entire frame transmission delay(long-term factor).Therefore,the optimization problem in the spectrum ... The transmission delay of realtime video packet mainly depends on the sensing time delay(short-term factor) and the entire frame transmission delay(long-term factor).Therefore,the optimization problem in the spectrum handoff process should be formulated as the combination of microscopic optimization and macroscopic optimization.In this paper,we focus on the issue of combining these two optimization models,and propose a novel Evolution Spectrum Handoff(ESH)strategy to minimize the expected transmission delay of real-time video packet.In the microoptimized model,considering the tradeoff between Primary User's(PU's) allowable collision percentage of each channel and transmission delay of video packet,we propose a mixed integer non-linear programming scheme.The scheme is able to achieve the minimum sensing time which is termed as an optimal stopping time.In the macro-optimized model,using the optimal stopping time as reward function within the partially observable Markov decision process framework,the EHS strategy is designed to search an optimal target channel set and minimize the expected delay of packet in the long-term real-time video transmission.Meanwhile,the minimum expected transmission delay is obtained under practical cognitive radio networks' conditions,i.e.,secondary user's mobility,PU's random access,imperfect sensing information,etc..Theoretical analysis and simulation results show that the ESH strategy can effectively reduce the transmission delay of video packet in spectrum handoff process. 展开更多
关键词 practical cognitive radio networks spectrum handoff process partially observable Markov decision process video transmission
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Semiclassical approximation for transmission through open Sinai billiards
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作者 蔡祥吉 张延惠 +3 位作者 李宗良 蒋国辉 杨秦男 徐学友 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期128-132,共5页
We use a semiclassical approximation to study the transport through the weakly open chaotic Sinai quantum billiards which can be considered as the schematic of a Sinai mesoscopic device,with the diffractive scattering... We use a semiclassical approximation to study the transport through the weakly open chaotic Sinai quantum billiards which can be considered as the schematic of a Sinai mesoscopic device,with the diffractive scatterings at the lead openings taken into account.The conductance of the ballistic microstructure which displays universal fluctuations due to quantum interference of electrons can be calculated by Landauer formula as a function of the electron Fermi wave number,and the transmission amplitude can be expressed as the sum over all classical paths connecting the entrance and the exit leads.For the Sinai billiards,the path sum leads to an excellent numerical agreement between the peak positions of power spectrum of the transmission amplitude and the corresponding lengths of the classical trajectories,which demonstrates a good agreement between the quantum theory and the semiclassical theory. 展开更多
关键词 Sinai billiards transmission amplitude classical trajectories power spectrum
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Adjustable transmission properties through ring-shaped nanotube arrays using finite-difference time-domain method
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作者 周凤麒 刘志敏 +1 位作者 李宏建 刘二根 《Journal of Central South University》 SCIE EI CAS 2014年第8期3013-3018,共6页
Metallic ring-shaped nanotube arrays are proposed and its optical transmission properties are studied by using finite-difference time-domain (FDTD) method. Compared with the transmission spectra of conventional circ... Metallic ring-shaped nanotube arrays are proposed and its optical transmission properties are studied by using finite-difference time-domain (FDTD) method. Compared with the transmission spectra of conventional circular nanotube arrays, two photonic band gaps are emerged in the transmission spectra offing-shaped nanotube arrays, the two band gaps and transmission spectra are adjusted by the length, inner radius, intertube spacing and the dielectric constants of the core and embedding medium, and magnitude modification, redshift and blueshift of the resonance modes are observed. A metallic ring-shaped nanotube arrays for subwavelength band-stop filter in the range of visible light can be achieved. To understand its physical origin, field-interference mechanism was suggested by the field distributions. The proposed nanostructures and results may have great potential applications in subwavelength near-field optics. 展开更多
关键词 ring-shaped nanotube arrays PLASMON transmission spectrum finite-difference time-domain (FDTD) OPTIMIZATION
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Three New Coordination Polymers Constructed by Adjusting the Angles of Pyridyl or Imidazolyl-based Synthons: Structures and Solid UV-vis Properties
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作者 周春辉 周杰 +2 位作者 胡振原 金矿 胡劲松 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第8期1245-1252,共8页
Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-y... Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-yl) diphenyl ether, bdc2- = 1,3-benzenedicarboxylate), were characterized by single-crystal X-ray diffraction, elemental analysis, PXRD, IR spectroscopy and TGA analysis.Complex 1 crystallizes in monoclinic, space group P21/n, with a = 9.1568(12), b = 16.943(2), c =15.441(2) A, β = 104.049(2)°, V = 2323.9(5) A^3, Dc = 1.420 g/cm^3, Mr = 993.83, F(000) = 1026, μ =0.440 mm-(-1) and Z = 2. Complex 2 crystallizes in monoclinic, space group P21/n, with a =9.1395(17), b = 17.019(3), c = 15.473(3) A, β = 104.651(2)°, V = 2328.5(7) A^3, Dc = 1.414 g/cm^3,Mr = 991.58, F(000) = 1024, μ = 0.487 mm^-1, Z = 2. Complex 3 also belongs to the monoclinic system, space group P21/n, with a = 11.4365(16), b = 18.346(3), c = 11.7068(17) A, β = 91.022(2)°,V = 2455.9(6) A3, Dc = 1.422 g/cm^3, Mr = 1051.66, F(000) = 1092, μ = 0.468 mm^-1, Z = 2. All complexes 1, 2 and 3 are 2D layer structures constructed from intermolecular hydrogen bonds. In addition, the solid UV-vis properties of complexes 1, 2 and 3 were also studied. 展开更多
关键词 metal-organic frameworks intermolecular hydrogen bonds solid uv-vis spectrum
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