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排序方式: 共有10000条查询结果,搜索用时 9 毫秒
71.
Silveira T. G. Teixeira A. L. J. Ferreira A. P. S. Monteiro P. M. N. P. 《Photonics Technology Letters, IEEE》2006,18(21):2212-2214
An all-optical setup to generate vestigial sideband signals based on self-phase modulation in a semiconductor optical amplifier is experimentally demonstrated at 10 Gb/s. Sideband suppressions higher than 15 dB are reported with improved eye opening. Wavelength-independent operation over 26 nm is demonstrated. Increased chromatic dispersion tolerance is verified: a receiver sensitivity penalty of 5.3 dB, relative to back-to-back, is obtained after transmission over 2720 ps/nm; whereas conventional double sideband is penalized by 4.0 dB after 1360 ps/nm 相似文献
72.
Charge recombination in reaction center (RC) of photosystem II(PS II) is regarded as the location of 685 nm delayed fluorescence
(DF). The mechanism of 730 nm component appearing in the DF spectrum for chloroplast was studied by various spectral analysis
methods. Experimental results of the DF spectrum at different chloroplast concentration show that the intensity of peaks at
685nm and 730 nm ascends with the chloroplast concentration increasing when the concentration is relatively low. When the
concentration increases to the level of 7.8μg/ml, a maximum intensity of the peak at 685 nm appears but the intensity of 730
nm peak still increases. The peak at 730 nm finally reaches a maximum intensity at the chloroplast concentration of 31.2 μg/ml
while the intensity of the 685 nm peak has apparently fallen down. The results of absorption spectrum show that the ratios
of A685 to A730 keep almost constant with the increasing of chloroplast concentration. Furthermore, the excitation spectrum
for 730 nm fluorescence shows that the 685nm light has high excitation efficiency. These results indicate that the 730 nm
component of DF spectrum is the fluorescence of chlorophyll in PS I RC excited by 685 nm DF. Meanwhile, this can be further
verified by the invariability of DF spectrum at different delay time (1 second∼9 seconds).
This research is supported by the National Natural Science Foundation of China (60378043), and supported by the Opening Foundation
of the Key Laboratory of Opto-Electronic Technology and Intelligent Control (Lanzhou Jiaotong University), Ministry of Education
(K04108) 相似文献
73.
Jun‐Da Chen Fang‐Biau Ueng Chien‐Hung Chen 《Wireless Communications and Mobile Computing》2015,15(1):71-86
In this paper, we propose three adaptive blind algorithms for multiuser multicarrier code division multiple‐access systems in multipath fading channels. The proposed adaptive blind receivers are based on the property of the discreteness of the input data symbol and are updated in every symbol interval. We also use the concept that the variance of the output signal approaches to the variance of the desired signal to get the cost function. The three proposed receiver structures are the traditional finite impulse response (FIR) structure, the despreading (DES) filter structure and the generalized sidelobe canceller (GSC) structure. The advantage of the FIR filter is that the length of the filter weights does not have to be the same length as the spreading code. For the DES filter, the combination of the adaptive weight and the despreading code has the simplest structure than the other two proposed receiver structures. The constrained GSC filter is superior to the other two proposed receiver structures in the environments dominated by multiple‐access interference. By this constraint, the blind GSC filter can guarantee to converge to the desired solution. Simulation results are given to show the effectiveness and comparison of the proposed adaptive blind receivers. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
74.
75.
笪林梅 《智能计算机与应用》2011,(2):74-75
顺序表是一种常见的,用一组地址连续的存储单元依次存储数据元素的线性结构.在顺序表上进行查找有多种方法,其中最生要的是顺序查找和二分查找两种方法.用这两种方法实现学生成绩查询功能各有优缺点. 相似文献
76.
P.M. Santos Vitor Costa M.C. Gomes Beatriz Borges Mário Lança 《Microelectronics Journal》2007,38(1):35-40
This work presents the design of LDMOS transistors fully compatible with a standard CMOS process, only requiring mask layout manipulation. A conventional 0.35 μm CMOS process was elected to demonstrate the viability of the approach. The prototyped LDMOS transistor exhibits a breakdown voltage of 24 V, which represents an improvement of 31% when compared with the high-voltage extended-drain NMOS available in the process library, while other static parameters remain in the same range. Furthermore, this solution enables the CMOS integration of a high-voltage pass-transistor, as a consequence of the formation of an isolated lightly doped p-type region inside the n-well. 相似文献
77.
78.
Nanoelectronics is a very promising step the world of electronics is taking. It is proved to be more efficient than the microelectronic approaches currently in use, mainly in terms of area and energy management. A Single-Electron Transistor (SET) is capable of confining electrons to sufficiently small dimensions, so that the quantization of both their charge and their energy is easily observable, making the SET's quantum mechanical devices. These features should allow building chips with a number of devices orders of magnitude greater than indicated by the roadmap still respecting area and power consumption restrictions. In this sense, Tera Scale Integrated (TSI) systems can be feasible in the future. A digital module, such as an arithmetic logic unit, completely implemented with SETs has already been proposed and validated by simulation. In this work a completely SET based network-on-chip (NoC) nanoelectronic core is proposed. Furthermore, a simple NoC architecture based on that nanoelectronic core is also evaluated. It is shown that the SET-based NoC has a promising performance considering parameters such as power consumption, area and clock frequency. A simple comparison of mesh NoC chip prototypes is shown. 相似文献
79.
直写ASIC技术的新发展 总被引:2,自引:0,他引:2
采用直写ASIC技术能缩短产品的研制周期,降低研制成本,无风险地进行了批量生产,加快ASIC投放市场的速度。分析了直写ASIC技术的特点,介绍了激光直写机的原理,展望了此项技术的应用前景。 相似文献
80.