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1.
A theorem concerning the inversion of a linear operator which is expressible as a combination of matrices is proved. Two examples, one in electrodynamics of moving media and the other involving a scaling operator in Lorentz transformation, are given to demonstrate its applications.  相似文献   

2.
The paper presents a new distribution network which is capable of concentrating and shifting the incoming active packets simultaneously, without requiring dummy destination address generation and extraction processes. It has the structure of a reverse banyan network (RBN) and consists of controlled switching elements (CSEs) which is obtained by extending the passive iterative-cells introduced by Narasimha [1994]. The CSE-based RBN has a set of external control inputs (ECIs) in addition to the data input and output lines and can generate different output patterns according to the ECI values. It is shown through four properties that the CSE-based RBN can perform the distribution function of the conventional distributor. In addition, it is rigorously described in the properties how to determine the set of ECI values to achieve the desired distribution function, which includes the distribution in the normal mode, in the reversed mode, and in alternation of these two modes. The proposed CSE-based distributor can be applied to a variety of occasions by modifying the use of the counter, the numbers to write on the registers, and the table to store the ECI values. Some of useful examples are demonstrated through applications to shift-sequence permutation, N×R concentration, nonblocking point-to-point switching, and virtual FIFO queueing  相似文献   

3.
A new analytical technique for calculating the 2-D potential distribution of a MESFET device operated in the subthreshold region is proposed, in which the 2-D Poisson's equation is solved by the Green's function technique. The potential and electric-field distributions of a non-self-aligned MESFET device are calculated exactly from different types of Green's function in different boundary regions, and the sidewall potential at the interface between these regions can be determined by the continuation of the electric field at the sidewall boundary. The remarkable feature of the proposed method is that the implanted doping profile in the active channel can be treated. Furthermore, a simplified technique is developed to derive a set of quasi-analytical models for the sidewall potential at both sides of the gate edge, the threshold voltage of short gate-length devices, and the drain-induced barrier lowering. Moreover, the developed quasi-analytical models are compared with the results of 2-D numerical analysis and good agreements are obtained  相似文献   

4.
通过对雷达回波数据的分析与理论研究,提出了一种基于目标回波特性的检测方法,并结合较低的虚警门限,提高了目标的检测概率,实现了参数的高精度提取。同时,由于该算法计算量小,适合全程全方位高精度点迹凝聚的实现。  相似文献   

5.
Let T be a continuous positive random variable representing the lifetime of an entity. This entity could be a human being, an animal or a plant, or a component of a mechanical or electrical system. For nonliving objects the lifetime is defined as the total amount of time for which the entity carries out its function satisfactorily. The concept of aging involves the adverse effects of age such as increased probability of failure due to wear. In this paper, we consider certain characteristics of the residual lifetime distribution at age t, such as the mean, median, and variance, as describing aging. Gamma and Weibull families of distributions are studied from this point of view. Explicit asymptotic expressions for the mean, variance and the percentiles of corresponding residual lifetime distributions are found. Finally these families of distributions are fitted to four sets of actual data, two of which are entirely new. The results can be used in discriminating different shape parameters.  相似文献   

6.
A new model of generalized invertor is presented, The model is generalized from the conventional K-, J-invertor. So it is easy to be applied directly to design microwave circuits such as impedance transformers, filters, and couplers of any complex discontinuities, when the symmetrical and asymmetrical networks are involved. The theory based on the new model is developed to enrich the microwave theory on network synthesis. Examples are given to show the effectiveness and convenience in application  相似文献   

7.
Recently, privacy concerns become an increasingly critical issue. Secure multi-party computation plays an important role in privacy-preserving. Secure multi-party computational geometry is a new field of secure multi-party computation. In this paper, we devote to investigating the solutions to some secure geometric problems in a cooperative environment. The problem is collaboratively computing the Euclid-distance between two private vectors without disclosing the private input to each other. A general privacy-preserving Euclid-distance protocol is firstly presented as a building block and is proved to be secure and efficient in the comparison with the previous methods. And we proposed a new protocol for the application in Wireless Sensor Networks (WSNs), based on the novel Euclid-distance protocol and Density-Based Clustering Protocol (DBCP), so that the nodes from two sides can compute cooperatively to divide them into clusters without disclosing their location information to the opposite side.  相似文献   

8.
Memristor is a new passive circuit element. The interaction of the memristor with other circuit elements is important for designers. In this paper, new memristor emulator circuit is designed using DDCC (differential difference current conveyor) based on CMOS. It is realized that the proposed emulator causes less complexity compared to other designed emulator circuits. Compatibility of memristor with CMOSs and its operation ability at high frequencies are very important for circuit design based on memristor. The emulator based on CMOS can manage to provide these two fundamental properties successfully. In order to test the proposed emulator, it is connected to memristor with both ways, serial and parallel, than MC circuit is analyzed and results are shown at the end of the paper.  相似文献   

9.
A three-dimensional Fourier transform (FT) of a linear function with triangular support is derived in its coordinate-free representation. The Fourier transform of this distribution is derived in three steps. First, the 2-D FT of a constant (top hat) function is obtained. Next, the distribution is generalized to a linearly varying function. Finally, the formulation is extended to a coordinate-free representation which is the 3-D FT of the 2-D function defined over a surface. This formulation is applied to the near-field computation, yielding accurate numerical solutions  相似文献   

10.
This paper develops the asymptotic sampling distribution of the inverse of the coefficient of variation (InvCV). This distribution is used for making statistical inference about the population CV (coefficient of variation) or InvCV without making an assumption about the population distribution. It applies to making inferences (point and interval estimation, and hypothesis-testing) about the shape parameter of some popular lifetime distributions like the Gamma, Weibull, and log-normal, when the scale parameter is unknown. The test procedure is used to test exponentiality against a Gamma or a Weibull alternative. The results are compared with those in the literature  相似文献   

11.
文章提出了一种新的突发分配业务模型,给出了这种业务模型的详细定义,并应用此模型和传统的非突发分配模型对光突发交换(OBS)中的交换机构进行了性能分析和对比.计算结果表明,当交换机构扇出比F=1、突发强度B1=2时,突发分配模式下的丢包率比非突发分配模式下的丢包率增加大约一个数量级.也许该突发业务模型并不能真实地反映现实世界的业务流,但其能提供一种逼近现实世界业务流的分析方法.  相似文献   

12.
A W-band high gain lens antenna has been realised and measured. A hyperbolic lens made in ECCOSTOCK 0005 is associated to an optimised modified circular horn related to a circular-to-rectangular waveguide transition in order to fit the WR-10 standard waveguide. The antenna provides more than 30 dBi gain between 75 and 110 GHz. It is competitive in several fields of applications: first, obstacle detection radar application (at 77 or 94 GHz), secondly metrology, for example, in order to measure radar cross-sections over the whole W-band with a single antenna.  相似文献   

13.
吕百达 《激光杂志》1984,5(1):55-58
本文利用高斯光束的复参数表示和ABCD定律推出一般情况下高斯光束的成象公式和物象比例公式,并对公式的几个应用实例予以说明。  相似文献   

14.
We propose a novel methodology for estimating the shape parameter of a generalized Gaussian distribution (GGD). This new method is based on a simple estimating equation derived from a convex shape equation. The estimating equation is completely independent of gamma and polygamma functions. Thus, no lookup table, interpolation, or additional subroutine to evaluate these functions are required for real-time implementations of the proposed method, which is in contrast to all existing methods. Furthermore, we establish that the shape equation has a unique global root on the positive real line and the Newton-Raphson root-finding algorithm converges to the unique global root from any starting point in a semi-infinite interval Thetamin. More importantly, we show that the sample-based shape estimating equation has a unique global root with probability tending to one and the root is consistent for the true shape parameter. Finally, we prove via fixed point arguments that, with probability tending to one, the Newton-Raphson algorithm converges to the unique global root of the sample shape estimating equation from any starting point in Thetamin. Some numerical experiments are also provided to demonstrate the global convergence and the excellent finite sample performance of the proposed method  相似文献   

15.
This article presents an extremely compact new formula for the symbol error probability in M-ary differential phase shift keying (MDPSK) that is extraordinarily similar to its counterpart for M-ary phase shift keying (MPSK). This result follows from a new form for a generic error probability associated with the phase angle between two vectors perturbed by Gaussian noise. The new form also leads to a new expression for the Marcum Q-function. As special cases, the generic error probability is noted to also contain MPSK, CPFSK, and digital FM. Finally, it is pointed out that the generic error probability simplifies the error probability expressions in other situations such as nonorthogonal signaling, maximum-likelihood differential detection of DPSK with block-by-block detection, and Gray coding of MDPSK  相似文献   

16.
陈智浩 《激光杂志》1992,13(2):67-69
本文利用高斯光束传播理论以及ABCD定律,导出了发散纤维透镜新的成象公式。  相似文献   

17.
This paper traces the development of the first passage time distribution of Brownian motion (inverse Gaussian) together with its various applications in inventory problems, usage and storage times, detection theory, labor turnover, money supply, purchasing models, hospital inpatient stay times, strikes duration, biology, … etc. Besides, since the inverse Gaussian distribution arises as the distribution of first passage time of Brownian motion, its applicability to lifetime modeling is a natural consequence. The general characteristics of the inverse Gaussian model which make it attractive for various applications are also identified.  相似文献   

18.
In this work, a new CMOS implementation of high transconductance current follower transconductance amplifier (CFTA) is proposed. The proposed CFTA uses current starving technique along with an auxiliary unit (AU) to enhance transconductance performance. The cross-drain-coupled MOSFETs are also used in AU which further enhances transconductance of proposed circuit. The proposed CFTA provides higher transconductance and wider tuning range without affecting its output swing and bandwidth performance. The proposed CFTA provides transconductance of 11.3 mS, dissipates 1.8 mW power and operates at?±?0.6 V supply voltage. A current mode third order quadrature oscillator and biquad filter have been designed and simulated, to validate the performance of proposed circuit. The workability of proposed CFTA and its applications have been verified by using Cadence virtuoso schematic composer with TSMC 0.18 µm process parameters.  相似文献   

19.
It is expected that the available spectrum for the proposed personal communication networks will soon be at a premium as the user population increases, and using multilevel quadrature amplitude modulation (MQAM), an bandwidth efficient transmission method for digital signals, may significantly ease the problem. A new lattice polynomial perceptron (LPP), with faster and less input signal-dependent convergence behavior, is presented and applied to frequency-selective slow fading channel equalization and adjacent-channel interference (ACI) suppression in a 16-QAM system. Computer simulation results are given, which shows that, in a 16-QAM system, the performance of LPP is clearly superior to that of the other structures  相似文献   

20.
从理论推导分析了键合片的缺陷分布与Weibull模数m之间的关系。此关系与实验相符,并利用此关系很好地解释了硅片键合强度随退火温度变化的关系。  相似文献   

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