In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach ...In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach and extensive computer simulations. The steady-state particle currents, the density profiles, and the phase diagrams are obtained. It is shown that with unequal injection rates and different hopping rates, the phase diagram structure is qualitatively changed. The theoretical calculations are in good agreement with Monte Carlo simulations.展开更多
Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A s...Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A simple approximate theory and extensive Monte Carlo computer simulations were used to calculate the steady-state phase diagrams and bulk densities. It is found that the phase diagram for local inhomogeneity in TASEP with different hopping rates p is qualitatively similar to homogeneous models. Interestingly, there is a saturation point pair (a*, fl*) for the system, which is decided by parameters p and q. There are three stationary phases in the system, when parameter p is fixed (i.e., p=0.8), with the increase of the parameter q, the region of LD/LD and HD/HD phase increases and the HD/LD is the only phase which the region shrinks. The analytical results are in good agreement with simulations.展开更多
Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas...Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas high throughput for entertainment application. However, for both applications, low energy consumption is requested. Multiple hops technics have been researching in many fields of wireless system, e.g., ad hod, mobile, ITS etc. and its energy-efficiency is reported to be high. We propose the multiple hops technic for WBAN, however, WBAN is different to another systems, almost sensors forward the vital data packet of another sensors while sensing and generating the data packet of itself. Therefore, according to a packet generation rate of all sensors, probabilities of successful transmission and packet loss because of collision, timeout and overflow, are changed. It means that the vital data is lost and the transmit power is wasted due to packet loss. In order to obtain the highest throughput and save the power, the successful transmission probability is analyzed and the packet generation rate is optimized for multiple hops WBAN that using CSMA/CA based on IEEE802.15.6. The numerical calculation result indicates that the optimized packet generation rate depends on the system model. Moreover, the relation between the system model, the optimized packet generation rate and the throughput is discussed in the paper.展开更多
常规慢速频移键控跳频(frequency-hopping/frequency-shift-keying,FH/FSK)受跟踪干扰威胁严重;差分跳频抗跟踪干扰能力强,但部分频带干扰下误码率高。为提高常规慢速跳频抗跟踪干扰性能,同时不损失抗部分频带干扰性能,提出的多序列...常规慢速频移键控跳频(frequency-hopping/frequency-shift-keying,FH/FSK)受跟踪干扰威胁严重;差分跳频抗跟踪干扰能力强,但部分频带干扰下误码率高。为提高常规慢速跳频抗跟踪干扰性能,同时不损失抗部分频带干扰性能,提出的多序列跳频(multi-sequence frequency hopping,MSFH)无线通信方式中,数据信道和补偿信道频率分别按不同跳频序列跳变,使干扰方无法准确跟踪补偿信道,减少了跟踪干扰影响;而接收机射频前端采用窄带接收,与差分跳频的宽带接收相比可有效抑制部分频带干扰。在瑞利衰落信道下,分析了卷积编码MSFH抗干扰性能。数值和仿真表明,在最坏跟踪干扰下MSFH比常规跳频约有5~10dB误码率性能增益,且抗部分频带干扰性能优于差分跳频。展开更多
基金supported by the National Scientific and Technological Support Project,China (Grant No.2006BAE03A00)
文摘In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach and extensive computer simulations. The steady-state particle currents, the density profiles, and the phase diagrams are obtained. It is shown that with unequal injection rates and different hopping rates, the phase diagram structure is qualitatively changed. The theoretical calculations are in good agreement with Monte Carlo simulations.
基金Project(2011FZ050) supported by Applied Basic Research Program of Yunnan Provincial Science and Technology Department,ChinaProject(2011J084) supported by Master Program of Yunnan Province Education Department,China
文摘Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A simple approximate theory and extensive Monte Carlo computer simulations were used to calculate the steady-state phase diagrams and bulk densities. It is found that the phase diagram for local inhomogeneity in TASEP with different hopping rates p is qualitatively similar to homogeneous models. Interestingly, there is a saturation point pair (a*, fl*) for the system, which is decided by parameters p and q. There are three stationary phases in the system, when parameter p is fixed (i.e., p=0.8), with the increase of the parameter q, the region of LD/LD and HD/HD phase increases and the HD/LD is the only phase which the region shrinks. The analytical results are in good agreement with simulations.
文摘Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas high throughput for entertainment application. However, for both applications, low energy consumption is requested. Multiple hops technics have been researching in many fields of wireless system, e.g., ad hod, mobile, ITS etc. and its energy-efficiency is reported to be high. We propose the multiple hops technic for WBAN, however, WBAN is different to another systems, almost sensors forward the vital data packet of another sensors while sensing and generating the data packet of itself. Therefore, according to a packet generation rate of all sensors, probabilities of successful transmission and packet loss because of collision, timeout and overflow, are changed. It means that the vital data is lost and the transmit power is wasted due to packet loss. In order to obtain the highest throughput and save the power, the successful transmission probability is analyzed and the packet generation rate is optimized for multiple hops WBAN that using CSMA/CA based on IEEE802.15.6. The numerical calculation result indicates that the optimized packet generation rate depends on the system model. Moreover, the relation between the system model, the optimized packet generation rate and the throughput is discussed in the paper.
文摘常规慢速频移键控跳频(frequency-hopping/frequency-shift-keying,FH/FSK)受跟踪干扰威胁严重;差分跳频抗跟踪干扰能力强,但部分频带干扰下误码率高。为提高常规慢速跳频抗跟踪干扰性能,同时不损失抗部分频带干扰性能,提出的多序列跳频(multi-sequence frequency hopping,MSFH)无线通信方式中,数据信道和补偿信道频率分别按不同跳频序列跳变,使干扰方无法准确跟踪补偿信道,减少了跟踪干扰影响;而接收机射频前端采用窄带接收,与差分跳频的宽带接收相比可有效抑制部分频带干扰。在瑞利衰落信道下,分析了卷积编码MSFH抗干扰性能。数值和仿真表明,在最坏跟踪干扰下MSFH比常规跳频约有5~10dB误码率性能增益,且抗部分频带干扰性能优于差分跳频。