A NEW FORMULA FOR INDUCTANCE OF ANISOTROPIC MAGNETIC MEDIA

By solving the basic equations of magnetic field in the anisotropic magnetic mediain which the tensor μik is symmetric,an integral formula for anisotropic vector potential A isobtained.By which the characteristic formulae for self and mutual inductances are derived inscalar and tensor forms,and their transformation formula are also derived.Finally,the formulais checked by practical examples.     

APPROXIMATION OF THE QUEUE LENGTH DISTRIBUTION OF GENERAL QUEUES

In this paper we develop an approximation formalism on the queue length distribution for general queueing models. Our formalism is based on two steps of approximation; the first step is to find a lower bound on the exact formula, and subsequently the Chernoff upper bound technique is applied to this lower bound. We demonstrate that for the M/M/1 model our formula is equivalent to the exact solution. For the DIM/1 queue, we find an extremely tight lower bound below the exact formula. On the other hand, our approach shows a tight upper bound on the exact distribution for both the ND/D/1 and M/D/1 queues. We also consider the M+Σ N_jD/D/1 queue and compare our formula with other formalisms for the Σ N_jD/D/1 and M+D/D/1 queues.     

General non-recursive coefficients calculation formula for sinc<Superscript><Emphasis Type="Italic">N</Emphasis></Superscript> filter

A general non-recursive formula is proposed for calculating impulse response coefficients of sinc ^N filter, which is made by N cascade-connected sinc filters with length of M. It is demonstrated that this formula is valid for all coefficients and suitable for general cases. Using it, different from other methods, each coefficient is independent to others and can be accessed directly due to its non-recursive characteristic.     

Testing process performance based on the yield: an application to the liquid-crystal display module

Process capability indices have been introduced to provide numerical measures on whether a manufacturing process is capable of reproducing items meeting the specifications predetermined by the product designers or the consumers. Process yield is one of the most common criteria used in the manufacturing industry for measuring process performance. The formula S_pk has been proposed to calculate the process yield for normal processes. The formula S_pk provides an exact measure on the process yield. Unfortunately, the statistical properties of the estimated are mathematically intractable. In this paper, we apply the bootstrap simulation method to construct the lower confidence bound of S_pk. We then present a real-world application to the liquid-crystal display module process, to illustrate how we may apply the formula S_pk to actual data collected from the factories.     

Improved formulae for the resonant frequencies of triangular microstrip patch antennas

In this article, an improved formula for the effective side length (a _eff) of the equilateral triangular patch antenna is presented. The computed resonant frequencies for the first five modes, using this formula, are compared with the available experimental and theoretical results in the literature. It is shown that the proposed formula has better accuracy than other available expressions. Moreover, the 30°–60°–90° and 30°–30°–120° triangular patch antennas are studied. Specifically, improved formulae for the effective dielectric constant of these patches are derived.     

A new formula and an algorithm for reliability analysis of networks

In 1978, Satyanarayana and Prabhakar (SP) proposed a new topological formula for the source-to-terminal (ST) reliability of complex networks. The formula generates only non-cancelling terms of the reliability expression which correspond one-to-one with the p-acyclic subgraphs of the given network. Based on the concept of neutral sequences in acyclic graphs, a powerful SP algorithm was presented for generating all p-acyclic subgraphs and computing the ST reliability of the network. Combining an inclusion-exclusion algorithm with a sum of disjoint products algorithm, we introduce a new topological formula which includes the SP formulas as a special case. A new efficient algorithm which has all features of the SP algorithm is proposed. In general, the reliability expressions obtained by this algorithm are more compact than the ones obtained by the SP algorithm.     

采用解析法估算弯曲波导超辐射发光二极管的光学损耗

器件弯曲区域的光学损耗对弯曲波导超辐射发光二极管(SLD)性能有着重要影响。对于器件制备和性能优化来说,若能对弯曲损耗作出估算,将大有裨益。在本论文中,我们推导出一个解析公式,可用于拟合器件P-I曲线而得到弯曲损耗系数。该公式已成功应用于对仿真P-I曲线损耗系数的估算(该P-I曲线通过一个复杂的量子点器件模型仿真得到),我们期待这一方法对估算实际器件损耗亦有效用。     

Exact reliability formulas for linear and circular m-consecutive-k-out-of-n:F systems

A linear (circular) m-consecutive-k-out-of-n:F system, consists of n components ordered on a line (on a circle). The system fails if and only if there are at least m nonoverlapping runs of k consecutive failed components. Four theorems are given. Theorem 1 is an exact formula of the reliability of the linear system given in terms of multinomial coefficients. Theorem 2 is an exact formula of the reliability of the linear system in terms of binomial coefficients. Theorems 3 and 4 are exact formulas of the reliability of the circular system, given in terms of multinomial and binomial coefficients, respectively.     

SER Analysis of QAM with Space Diversity in Rayleigh Fading Channels

This paper derives the symbol error probability for quadrature amplitude modulation(QAM) with L-fold space diversity in Rayleigh fading channels. Two combining techniques, maximal ratio combining(MRC) and selection combining(SC), are considered. The formula for MRC space diversity is obtained by averaging the symbol error probability of M-ary QAM in an additive white Gaussian noise(AWGN) channel over a chi-square distribution with 2L degrees of freedom. The obtained formula overcomes the limitations of the earlier work, which has been limited only to deriving the symbol error rate(SER) of QAM with two branch MRC space diversity. The formula for SC space diversity is obtained by averaging the symbol error probability of M-ary QAM in an AWGN channel over the distribution of the maximum signal-to-noise ratio among all of the diversity channels for SC space diversity. No analysis for QAM with SC space diversity has been reported yet. Analytical results show that the probability of error decreases with the order of diversity. We can also see that the incremental diversity gain per additional branch decreases as the number of branches becomes larger. On the other hand, the performance of 16 QAM with MRC becomes much better than that of SC as the number of branches becomes larger. By giving the order of diversity, L, and the number of signal points, M, we have been able to obtain the SER performance of QAM with general space diversity. These results can be used to determine the order of diversity to achieve the desired SER in land mobile communication system employing QAM modulation.     

A New Formula to Predict the Exact Detection Probability of a Generalized Order Statistics CFAR Detector for a Correlated Rayleigh Target

In this paper we present a new formula which can predict the exact detection probability of a generalized order statistics (GOS) constant false alarm rate (CFAR) detector for a partially correlated Rayleigh target model (0 < ρ < 1) in a closed form, where ρ is the correlation coefficient between returned pulses. By simply substituting a set of specific coefficient into the derived formula, one can obtain the detection probability of any kind of CFAR detector. Detectors may include the order statistics CFAR detector, the censored mean level detector, and the trimmed mean CFAR detector, but are not necessarily restricted to them. The numerical result for the first order Markov correlation model as applied to some of the detectors shows that as p increases from zero to one, higher signal-to-noise ratio is required to achieve the same detection probability.     

Identification of nonminimum phase FIR systems via fourth-order cumulants and genetic algorithm

In this paper, the problem of estimating the parameters of an FIR system from only the fourth-order cumulants of the noisy system output is considered. The FIR system is driven by a symmetric, independent, and identically distributed (i.i.d) non-Gaussian sequence. We propose a new formula called Weighted Overdetermined C(q, k) (WOC(q, k)) by extending the conventional C(q, k) formula. The optimal selection of the weights in WOC(q, k) is performed by using the Genetic Algorithm (GA) optimization method which minimizes a nonlinear error function based on the fourth-order cumulants alone. Simulations are provided to reveal the effectiveness and the superiority of this novel technique over the C(q, k) and other existing techniques.     

On the synchronizing band of a rational harmonic injection locking

 Compared with the harmonic injection locking(HIL),a rationai harmonic injection locking (RHIL)can make the circuit even simpler and more flexible.A common formula for the synchro- nizing band ⊿ω(s_m)max of the RHIL is derived and analysed in this paper.The result shows that the formula given by Schmideg(1971)is only its special case.A method for extending the RHIL\'s synchronizing band with full-pass network is presented.Using the method,a 2/3 injection locking VHF divider consisting of the FZ1C,a type of IC,is developed,with a stability factor n=⊿f_((3/2)max)/ ⊿f_((-40-+85℃))≥4;while for the original circuit,n≈0.6.Thus,the RHIL may be of more practical value in applications.     

基于不同器件结构的多指HBT热电稳定性研究

本文基于不同的器件结构同时对多指HBT器件的热稳定性和电稳定性进行了分析和讨论。通过直流测试、热阻计算以及基于S参数的稳定性因子K的计算,评估了两个不同版图结构的HBT器件的热稳定和电稳定特性,实验结果表明高热稳定性的器件具有低电学稳定性。引入一个基于小信号等效电路模型的K稳定因子公式对实验结果进行了合理解释。同时基于该公式,具有热镇流电阻结构的器件稳定性也进行了讨论。     

g-Representations and differential equations

This paper extends earlier results concerningg- andh-representations for nonlinear input-output maps so that vector-valued inputs and outputs can be treated. It establishes that the range of applicability of the extended results is very wide, and it illustrates how they can be used, within the context of systems governed by differential equations. In particular, it is shown that the nonlinear variation of constants formula is a special case of our main representation theorem.     

Infinite networks and quadratic optimal control

A discrete-time quadratic optimal control problem is shown to be equivalent to an infinite cascade ofn-port electrical networks. Both problems can be expressed as a generalized Schur complement (or shorted operator) of a block tridiagonal operator. Using Maxwell's principle for resistive networks, a variational formulation of the cascade limit ofn-port networks is given. For one special case a formula for the solution of the quadratic control problem is given in terms of the geometric mean of operators.     

A symbolic reliability of multiple path required system with three states

The system reliability of a “j or more paths required system” can be obtained from the probability that there is no minimal path suffering a short-mode failure and there is at least one set of j separate paths not suffering an open-mode failure. In order to evaluate the system reliability, we use the method of generating the sum of disjoint products, which is widely used for two-state systems. Some rules and a procedure for the minimized reliability formula are presented.     

On the convolutional square root of a Nyquist pulse

An explicit formula is developed for the pulse which, when convolved with itself, yields the well-known quasibandlimited Nyquist pulse for data transmission. As expected, the newly derived pulse produces zero intersymbol interference at theoutput of a filter matched to itself. Comparisons are offered with the well-known class of root raised cosine pulses.     

Common-cause failure analysis of a redundant system with non-repairable units

This paper presents a newly developed generalized expression for mean time to failure, MTTF, of a non-repairable identical unit parallel system with warm standby and common-cause failures. Also presented is a modified version of this formula that takes into account the repairability of the warm standby and/or switching mechanism. Generalized expressions for system reliability and variance of time to failure are presented along with some tables and plots of system reliability and MTTF.     

Markov model for k-out-of-n:G systems with built-in-test

This paper considers some new variations when the Built-In-Test technique is applied to k-out-of-n:G systems. A complete Markov model for the reliability and availability analysis of k-out-of-n:G systems with BIT is developed. Both fault coverage and false alarm are considered. A new inverse Laplace transform formula is derived to solve the differential simultaneous equations. Finally, generalized analytical functions for system reliability and availability are obtained. Our approach and solution are helpful and applicable for analyzing the impact of BIT design parameters on k-out-of-n:G system RAM and optimizing the redundancy management strategy.     

光电倍增管对高斯脉冲的响应

本文用脉冲响应函数法分析光电倍增管(PM)对高斯光脉冲的响应,用计算结果解释实验观测的波形及利用公式τp=√τt2-τ02从输出脉宽τt扣除PM引起的增宽τ0,求得输入脉宽τp 的条件及限制。