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181.
In the era of the nanometer CMOS technology, due to stringent system requirements in power, performance and other fundamental physical limitations (such as mechanical reliability, thermal constraints, overall system form factor, etc.), future VLSI systems are relying more on ultra-high data rates (up to 100 Gbps/pin or 20 Tbps aggregate), scalable, re-configurable, highly compact and reliable interconnect fabric. To overcome such challenges, we first explore the use of multiband RF/wireless-interconnects wh...  相似文献   
182.
Previously, we proposed that the dielectric layer of RF MEMS switch can be fabricated either on the transmission line, as traditional switches, or on the lower surface of the bridge. This paper presents a detailed comparison of the RF MEMS switches with different positions of dielectric layer. Through theoretically analyzing the physical model of fringing capacitance, it is revealed that different positions of dielectric layer can result in different switch capacitances. Therefore, the change of d...  相似文献   
183.
There are many reasons to worry that the current congestion control schemes in the Internet may be reaching its limits. Since the nature is a source of excellent solutions for complex problems, this work attempts to solve the congestion control problem, by adopting some biological principles and mechanisms. The current work proposes that the congestion problem in the Internet can be addressed through an inspiration from the population control tactics in nature. Toward this idea, each flow (W ) in the networ...  相似文献   
184.
In this paper,we propose a receiving system for impulse radio ultra-wideband (IR-UWB) communications,in which the data and reference pulses are combined as one signal to transmit,and the received signal can be divided into the data and reference pulses in the receiver end using the energy concentration property of Chirp pulses in fractional Fourier transform (FrFT) domain.A detailed theoretical analysis of the proposed system is given,and the formulation of bit error rate (BER) is obtained.Then according to...  相似文献   
185.
The equal circle packing problem is a well-known challenge in geometry.It is also a natural,clear and fair test system for global optimization.This paper presents a quasi-physical global optimization algorithm for solving the equal circle packing problem.The algorithm simulates two kinds of movements of N elastic disks: smooth movement driven by elastic pressures and violent movement driven by strong repulsive forces and attractive forces.The smooth movement makes the disks reach a locally optimal configura...  相似文献   
186.
Growth in population, decrease in arable land area, and change in climate are endangering our food security. Precision agriculture has the potential to increase crop productivity thorough tailored agricultural practices for different growing areas. Many models of crops and agro-ecosystems capable of predicting interaction between plants and environments have been developed for precision agriculture. Currently, there are several representative categories of crop and agro-ecosystem models, including the de Wi...  相似文献   
187.
In this research, a closed-loop drip irrigation control hybrid wireless sensor and actuator network (HWSAN) prototype were developed and deployed in a crop field for soil property precise measurement and precision irrigation in accordance with the measured soil property. The HWSAN was composed of a wireless sensor and actuator network (WSAN) used for in-field soil property monitoring and irrigation control and a laboratory supervising system. The WSAN included ten sensor nodes, five irrigation control nodes...  相似文献   
188.
Salient structural elements are ubiquitous in natural textures, and their distribution exhibits some stochastic distribution features. Current texture synthesis algorithms can neither preserve the integrity of the elements nor capture this distributive information. We present an algorithm to treat this high-level visual information. Here, we address the issue by taking specific care of the structural elements. Our texture synthesis process grows the target texture one structural element at a time. A Markov ...  相似文献   
189.
For the large quantity of data,rules and models generated in the course of computer generated forces (CGFs) behavior modeling,the common analytical methods are statistical methods based on the tactical rules,tactical doctrine and empirical knowledge.However,from the viewpoint of data mining,we can find many of these analytical methods are also each-and-every different data mining methods.In this paper,we survey the data mining theory and techniques that have appeared in the course of CGF behavior modeling f...  相似文献   
190.
We propose and experimentally demonstrate the heterodyne mixing and polarization diversity tech- niques in radio over fiber (ROF) systems with the advantages of high sensitivity and dispersion endurance. The generation of 2.5 Gb/s optical DPSK and PSK signals, fiber propagation and wireless transmission over 15 GHz subcarrier are illustrated with very low sensitivity of -26 and -32 dBm, respectively. Moreover, based on the wireless polarization diversity techniques, we successfully performed the t...  相似文献   
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