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91.
用强度系列成象法获取或显示高动态范围图象 总被引:1,自引:0,他引:1
提出一种适合于高动态范围图象的获取和显示的强度系列成象法。改变输入图象的强度,微机控制的图象采集系统进行记录得到一组磁盘文件,形成强度图象系列。基于记录的系列图象,可以进行信息提取、变换和显示等操作。基于获得的图象系列,提出一种剪贴操作进行快速的非线性图象变换。给出对光学功率谱处理的一个实例,它相当于进行锯齿形的非线性变换。 相似文献
92.
作者在本文中指出了吉比特网络的目标及其所带来的问题,采用了提出问题并回答问题(或说明可能答案)的方法来阐明。 相似文献
93.
Anna Hać 《Journal of Network and Systems Management》1994,2(1):49-62
This paper analyzes the performance of a switching architecture. The performance measures include the elapsed time of packet transfer and the waiting time to begin transfer. The architecture is partitioned depending on the type of network used and the expected traffic in the network. Every partition has a switch with a buffer that can absorb surges of bursty traffic within the network partition. The buffer size depends on the type of the network and incoming traffic. The partition size depends on the network bandwidth, network traffic, packet size and buffer size. Examples of different networks are used to show the applications of the model. The results show that the elapsed time of packet switch transfer depends exponentially on the number of partitions in the network. 相似文献
94.
文中介绍一种一氧化碳检测报警器,利用恒电位电解法原理制成的传感器,并配以最新电子元器件组成检测仪。用于对矿井、化工、煤炭、电力、冶金、环保等有关部门的一氧化碳检测。 相似文献
95.
本文报导一种新型的光纤氧、二氧化碳复合传感器.通过在同一敏感膜载体上固定两种不同的荧光试剂——芘丁酸及羟基芘三磺酸,制作了一种对氧和二氧化碳敏感的复合敏感膜.该传感器在医学临床检验范围内具有良好的线性,其测氧的分辩率是0.1%,测二氧化碳的分辩率是0.5%,响应时间短于1min.文中还讨论了三种敏感膜载体的比较及复合传感器测量进程中氧和二氧化碳的相互干扰问题. 相似文献
96.
α,ω-Methacrylate-terminated poly(1,3-dioxolane)s (polyDXL) were synthesized by cationic ring-opening polymerization of DXL in the presence of methylene-bis(oxyethylmethacrylate) as transfer agent. If the initiator concentration is small compared with the transfer agent concentration, the molecular weights of the polymers are governed by the ratio of the reacted monomer to the reacted transfer agent. The α,ω-methacrylate-terminated polyDXLs obtained undergo free radical polymerization with formation of polyacetal networks. The properties of the networks as function of the molecular weight of the corresponding prepolymers are reported. 相似文献
97.
A mixed mode digital/analog special purpose VLSI hardware implementation of an associative memory with neural architecture is presented. The memory concept is based on a matrix architecture with binary storage elements holding the connection weights. To enhance the processing speed analog circuit techniques are applied to implement the algorithm for the association. To keep the memory density as high as possible two design strategies are considered. First, the number of transistors per storage element is kept to a minimum. In this paper a circuit technique that uses a single 6-transistor cell for weight storage and analog signal processing is proposed. Second, the device precision has been chosen to a moderate level to save area as much as possible. Since device mismatch limits the performance of analog circuits, the impact of device precision on the circuit performance is explicitly discussed. It is shown that the device precision limits the number of rows activated in parallel. Since the input vector as well as the output vector are considered to be sparsely coded it is concluded, that even for large matrices the proposed circuit technique is appropriate and ultra large scale integration with a large number of connection weights is feasible. 相似文献
98.
The performance of sequential decoding of long constraint length convolutional codes is evaluated for Rayleigh fading channels. Sequential decoding is not practical below a certain theoretical signal-to-noise ratio, and these theoretical limits are calculated for a number of modulation methods and code rates. As an example, with BPSK modulation, soft decisions and code rate 1/2, the theoretical signal-to-noise ratio per information bit is 5.7 dB. Above this limit the bit error rate can be made arbitrarily small by increasing the constraint length at no significant complexity cost. Furthermore, it is shown that with carefully chosen quantization steps, 8 level uniform quantization gives a negligible loss also for sequential decoding on a Rayleigh fading channel. Simulation results using 8 level quantization correspond well with the theoretical performance bounds. Also, the performance on a correlated channel with finite interleaving has been obtained. With an interleaver depth of 50×50 and a normalized doppler frequency equal to 0.01 we are only 0.5 dB away from the performance with perfect interleaving. Finally, bit error rate results show this scheme to compete well with Turbo codes. 相似文献
99.
分子印迹技术及其应用 总被引:3,自引:0,他引:3
分子印迹技术是将高分子科学、材料科学、生物学、化学工程等有机集成。基于分子印迹技术所制备的分子印迹聚合物具有选择性高、稳定性好、应用范围广等特点 ,近年来得到了日益广泛和深入的研究。介绍了分子印迹技术的原理、分子印迹聚合物的制备方法、分子印迹技术的应用场合和实例 ,并简要预测了分子印迹技术领域未来的发展趋势。 相似文献
100.
高含蜡原油管道停输后的再启动问题非常复杂。它涉及因素多,问题的非线性很强。而有足够多神经元的S型三层神经网络理论上可逼近任意有理函数。文章采用误差反向传播网络预测环道实验装置中的启动压力,得到了较好结果。 相似文献