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1.
尚鸿雁 《半导体光电》2008,29(6):859-861,967
位置敏感探测器(PSD)的响应时间直接影响其动态探测入射光位置的准确性.分析了电势堆积现象,以四边形二维PSD为例,建立了PSD响应时间的仿真模型,分析了对响应时间的影响因素.结果表明,PSD响应时间随着光敏面大小、p型层电阻值以及级间电容的增大而同比例增大;在PSD器件的结构参数和物性参数不变的情况下,光源入射能量与器件的响应时间无关.  相似文献   

2.
A heterogeneous multicore system-on-chip (SoC) has been developed for high-definition (HD) multimedia applications that require secure DRM (digital rights management). The SoC integrates three types of processors: two specific-purpose accelerators for cipher and high-resolution video decoding; one general-purpose accelerator (MX); and three CPUs. This is how our SoC achieves high performance and low power consumption with hardware customized for video processing applications that process a large amount of data. To achieve secure data control, hardware memory management and software system virtualization are adopted. The security of the system is the result of the cooperation between the hardware and software on the system. Furthermore, a highly tamper-resistant system is provided on our SiP (System in a package), through DDR2 SDRAMs and a flash memory that contain confidential information in one package. This secure multimedia processor provides a solution to protect contents and to safely deliver secure sensitive information when processing billing transactions that involve digital content delivery. The SoC was implemented in a 90 nm generic CMOS technology.   相似文献   

3.
传统的灾备系统对于灾备资源未能充分利用,如何将庞大的灾备资源充分利用,避免资源的浪费一直备受关注。本文着重从一类非实时业务系统的灾备系统资源再利用研究和实现方面进行介绍和分析,在全面认识和分析灾备系统建设的特点基础上,阐述了针对非实时业务系统的灾备资源再利用的研究方向。  相似文献   

4.
Passivity Analysis of Neural Networks With Time Delay   总被引:4,自引:0,他引:4  
The passivity conditions for delayed neural networks (DNNs) are considered in this paper. We firstly derive the passivity condition for DNNs without uncertainties, and then extend the result to the case with time-varying parametric uncertainties. The proposed approach is based on a Lyapunov–Krasovskii functional construction. The passivity conditions are presented in terms of linear matrix inequalities, which can be easily solved by using the effective interior-point algorithm. Numerical examples are also given to demonstrate the effectiveness of the theoretical results.  相似文献   

5.
When scheduling cluster tools under wafer residency time constraints, wafer sojourn time in a processing module should be carefully controlled such that it is in a permissive range. Activity time variation often results in wafer sojourn time fluctuation and makes an originally feasible schedule infeasible. Thus, it is very important to know how the wafer sojourn time changes when activity time varies. With bounded activity time variation considered, this paper conducts a detailed analysis of wafer sojourn time variation in dual-arm cluster tools. To do so, a Petri net (PN) model and a real-time control policy are presented. Based on the PN model, real-time operational architecture, and real-time control policy, this paper analyzes the effect of activity time variation on wafer sojourn time delay at a process module and presents its upper bounds. The upper bounds are given in an analytical form and can be easily evaluated. With the wafer sojourn time analysis, it is possible to develop an effective method for schedulability analysis and optimal steady-state scheduling. An example is used to show the applications of the proposed approach.   相似文献   

6.
传输线时域响应分析中的改进型NILT方法   总被引:5,自引:2,他引:3  
本文利用拉氏变换的推广定义及初值定理,获得一种传输线时域响应分析的改进型数字拉氏逆变换(NILT)方法。该方法采取了将分析时间分段并进行传输线初始条件重新设置的步骤,因而比传统的NILT方法精确、有效。  相似文献   

7.
Systems are considered consisting of an arbitrary number of multiconductor transmission lines joined and terminated by arbitrary linear networks. The fines are assumed to be Iossy, with frequency-dependent parameters. The system is analyzed in the frequency domain, and the inverse Fourier transform is used to obtain the time-domain response.  相似文献   

8.
多重缓冲条件下消息最大响应时间算法的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
窦强  周兴铭 《电子学报》2002,30(5):632-635
分布式实时系统是实时系统的一个重要研究方向,有着广泛的应用背景,消息最大响应时间的定量分析是该研究方向中的一个关键问题。本文针对采用TDMA办议的分布式实时系统提出了一种多重缓冲条件下的消息最大响应时间算法,对该条件下消息的最大响应时间做出了完整、精确的分析,从而进一步扩展了该类算法的适用范围。  相似文献   

9.
提出一种传输线瞬态响应的时域分析方法。该方法对电报方程在时域内差分离散,在建立对空间的一阶微分方程组后,采用精细积分法,可获得传输线瞬态响应。这是一种时域内的半解析数值计算方法,具有方法简单、计算精度高等优点,能够有效地分析具有非线性负载的有损耦合传输线瞬态响应问题,也可以用于输电线路的瞬态分析及故障测距。  相似文献   

10.
随着Web应用的迅速增长,Web的服务质量(QoS)已经引起普遍关注。Web服务响应时间是用户评估Web服务质量最直观的一个参数。提出了一种基于HTTP测量Web服务响应时间的方法,并给出了在Visual C++的编译环境下使用WinSock控件编程的具体实现。测试软件独立于浏览器,实现了对Web服务器的实时测试、循环测试、平均响应时间测试以及不同站点响应时间测试功能。对程序设计中涉及的响应信息及其处理、基于HTTP的重定向等关键问题进行了详细讨论。测试结果表明软件运行稳定,能够满足对Web服务响应时间的各种测试需求。  相似文献   

11.
Switches with a shared buffer have lower packet loss probabilities than other types of switches when the sizes of the buffers are the same. In the past, the performance of shared buffer switches has been studied extensively. However, due to the strong dependencies of the output queues in the buffer, it is very difficult to find a good analytical model. Existing models are either accurate but have exponential complexities or not very accurate. In this paper, we propose a novel analytical model called the Aggregation model for switches with shared buffer. The model is based on the idea of induction: first find the behavior of two queues, then aggregate them into one block; then find the behavior of three queues while regarding two of the queues as one block, then aggregate the three queues into one block; then aggregate four queues, and so on. When all queues have been aggregated, the behavior of the entire switch will be found. This model has perfect accuracies under all tested conditions and has polynomial complexity.  相似文献   

12.
Data broadcast has been considered a promising way of information dissemination to a massive number of users in a wireless communication environment. Reducing user-waiting time is a major problem in developing a data broadcast system. There are two approaches for this problem; One is to design a broadcast schedule at the server side which reduces the mean response time, and the other is to utilize a local cache at the user side which may respond to a user request instantly. Though these two approaches were addressed separately in the literature, they may be taken jointly for better performance. The performance of system with joint approach depends on several factors such as broadcast schedule, cache size, cache management strategy, etc. In this paper we analyze response time in a data broadcast system with joint approach in which information items are structurally related with each other as in WWW. Based on the worst-case assumption, we derive a lower bound on the system performance for a given set of broadcast schedule, cache size, and cache management strategy. This result will be of help for designing and developing a data broadcast system. We support our analysis by carrying out an extensive simulation on some interesting proposed broadcast schedules and cache management strategies.  相似文献   

13.
从理论上分析了预倾角对液晶动力学的影响,推导出一系列可用于描述预倾角非0条件下的液晶响应分析公式.使用垂直取向的液晶盒能够通过实验验证理论分析的正确性,这一发现将预倾角与液晶响应时间定量的联系在一起.对预倾角和液晶响应时间的关系的研究,将加深我们对液晶动力学过程的理解,从而有助于优化液晶的响应时间.  相似文献   

14.
从理论上分析了预倾角对液晶动力学的影响,推导出一系列可用于描述预倾角非0条件下的液晶响应分析公式。使用垂直取向的液晶盒能够通过实验验证理论分析的正确性,这一发现将预倾角与液晶响应时间定量的联系在一起。对预倾角和液晶响应时间的关系的研究,将加深我们对液晶动力学过程的理解,从而有助于优化液晶的响应时间。从理论上分析了预倾角对液晶动力学的影响,推导出一系列可用于描述预倾角非0条件下的液晶响应分析公式。使用垂直取向的液晶盒能够通过实验验证理论分析的正确性,这一发现将预倾角与液晶响应时间定量的联系在一起。对预倾角和液晶响应时间的关系的研究,将加深我们对液晶动力学过程的理解,从而有助于优化液晶的响应时间。  相似文献   

15.
Pretilt angle effect on liquid crystal dynamics is analyzed theoretically. Analytical expressions are derived to describe liquid crystal response time under nonzero pretilt angle conditions. The theoretical analysis is confirmed experimentally using vertically aligned liquid crystal cells. This finding quantitatively correlates pretilt angles with liquid crystal response time. This study improves the understanding of the liquid crystal dynamic process which is helpful for optimizing liquid crystal response time.  相似文献   

16.
Xiangyi  Nie  Haiqing  Xianyu  Ruibo  Lu  Thomas  X.Wu  Shin-Tson  Wu  何志群 《现代显示》2008,19(2):7-11
从理论上分析了预倾角对液晶动力学的影响,推导出一系列可用于描述预倾角非0条件下的液晶响应分析公式.使用垂直取向的液晶盒能够通过实验验证理论分析的正确性,这一发现将预倾角与液晶响应时间定量的联系在一起.对预倾角和液晶响应时间的关系的研究,将加深我们对液晶动力学过程的理解,从而有助于优化液晶的响应时间.  相似文献   

17.
红火闹新春     
  相似文献   

18.
A multicore system-on-chip (SoC) has been developed for various applications (recognition, inference, measurement, control, and security) that require high-performance processing and low power consumption. This SoC integrates three types of synthesizable processors: eight CPUs (M32R), two multi-bank matrix processors (MBMX), and a controller (M32C). These processors operate at 1 GHz, 500 MHz, and 500 MHz, respectively. These three types of processors are interconnected on this chip with a high-bandwidth multi-layer system bus. The eight CPUs are connected to a common pipelined bus using a cache coherence mechanism. Additionally, a 512-kB L2 cache memory is shared by the eight CPUs to reduce internal bus traffic. A multi-bank matrix processor with 2-read/1-write calculation and background I/O operation has been adopted. The 1-GHz CPU is realized using a delay management network which consists of delay monitors that can be applied for any kind of application or process technology. Our configurable heterogeneous architecture with nine CPUs and two matrix processors reduces power consumption by 45%.  相似文献   

19.
基于防危核(壳)的安全关键硬实时系统响应时间的分析   总被引:1,自引:1,他引:0  
黎忠文  陈亮  熊光泽 《电子学报》2006,34(4):647-652
基于响应时间的可调度分析是设计硬实时系统的基础.防危核(壳)是安全关键硬实时系统的一种新防危措施,现有的普适响应时间分析方法不能适用于这类系统.本文的贡献在于采用检测点时间冗余容错和优先级提升思想,通过分析内/外错误、隐/显错误,提出了一种合适的响应时间分析方法,从而为这类系统提供有效的离线可调度分析工具,同时也为这类系统设计了一种基于检测点的容错方案.本方法稍作修改也可为其它安全关键系统服务.最后通过仿真实验验证了本方法的有效性和优越性.  相似文献   

20.
光学遥感卫星的辐射定标是卫星数据定量化应用的前提条件,针对静止轨道大面阵光学载荷成像特点,提出一种基于分时-分视场成像的在轨相对辐射定标方法。选取合适的亮、暗均匀场地,通过卫星姿态机动完成整个视场的定标,得到所有探元在轨相对辐射定标系数,可有效解决现有场地难以覆盖卫星视场而带来的在轨相对辐射定标难题。  相似文献   

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