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991.
We consider an M/G/1 queue with different classes of customers and discriminatory random order service (DROS) discipline. The DROS discipline generalizes the random order service (ROS) discipline: when the server selects a customer to serve, all customers waiting in the system have the same selection probability under ROS discipline, whereas customers belonging to different classes may have different selection probabilities under DROS discipline. For the M/G/1 queue with DROS discipline, we derive equations for the joint queue length distributions and for the waiting time distributions of each class. We also obtain the moments of the queue lengths and the waiting time of each class. Numerical results are given to illustrate our results.  相似文献   
992.
We investigate asymptotic behavior of the C0-semigroup T(t) associated with the mono-tubular heat exchanger equation with output feedback by a perturbation method. It is shown that T(t) is bounded if a constraint is satisfied by the parameters and the spatial distribution function. Further, applying the Arendt-Batty-Lyubich-Vu theorem, a criterion is established to judge strong stability of T(t).  相似文献   
993.
We consider the stochastic input-output properties of a simple non-linear dynamical system, the so-called Page-Hinkley detector, playing a key role in change detection, and also in queuing theory. We show that for L-mixing inputs with negative expectation the output process of this system is L-mixing. The result is applied to get an upper bound for the false alarm rate. The proof is then adapted to get a similar result for the case of random i.i.d. inputs. Possible extensions and open problems are given in the discussion.  相似文献   
994.
Optimal design for generalized linear models has primarily focused on univariate data. Often experiments are performed that have multiple dependent responses described by regression type models, and it is of interest and of value to design the experiment for all these responses. This requires a multivariate distribution underlying a pre-chosen model for the data. Here, we consider the design of experiments for bivariate binary data which are dependent. We explore Copula functions which provide a rich and flexible class of structures to derive joint distributions for bivariate binary data. We present methods for deriving optimal experimental designs for dependent bivariate binary data using Copulas, and demonstrate that, by including the dependence between responses in the design process, more efficient parameter estimates are obtained than by the usual practice of simply designing for a single variable only. Further, we investigate the robustness of designs with respect to initial parameter estimates and Copula function, and also show the performance of compound criteria within this bivariate binary setting.  相似文献   
995.
The Transmission Disequilibrium Test (TDT) detects linkage between a marker and a disease-susceptibility locus in the presence of linkage disequilibrium. The TDT requires data on the genotypes of affected offspring and their parents, which might not always be available. For example, for late onset diseases it might be difficult to find parents still alive, or genotypes of offspring might not be available. Genotyping unaffected siblings, combining different genotype data sets, or assuming a model mechanism for missing parents have all been proposed to deal with missing genotypes in parents but not in offspring. In this paper, we propose a Mendel Inheritance-Transmission Disequilibrium Test (MI-TDT) to impute missing genotypes in any members of a family with two affected offspring. Our method does not require any of the remedies mentioned above but simply utilizes the fundamental property of Mendel Inheritance on the transmission of alleles from parents to offspring. Most importantly, the MI-TDT reassures researchers about the declared significant genes when incomplete data is ignored. We illustrate the MI-TDT by identifying significant genes in type 1 diabetes from the Warren families in the United Kingdom.  相似文献   
996.
Based on the method of (n,k)-universal sets, we present a deterministic parameterized algorithm for the weighted rd-matching problem with time complexity O(4(r−1)k+o(k)), improving the previous best upper bound O(4rk+o(k)). In particular, the algorithm applied to the unweighted 3d-matching problem results in a deterministic algorithm with time O(16k+o(k)), improving the previous best result O(21.26k). For the weighted r-set packing problem, we present a deterministic parameterized algorithm with time complexity O(2(2r−1)k+o(k)), improving the previous best result O(22rk+o(k)). The algorithm, when applied to the unweighted 3-set packing problem, has running time O(32k+o(k)), improving the previous best result O(43.62k+o(k)). Moreover, for the weighted r-set packing and weighted rd-matching problems, we give a kernel of size O(kr), which is the first kernelization algorithm for the problems on weighted versions.  相似文献   
997.
We formulate a generalization of the NP-complete rectangle packing problem by parameterizing it in terms of packing density, the ratio of rectangle areas, and the aspect ratio of individual rectangles. Then we show that almost all restrictions of this problem remain NP-complete and identify some cases where the answer to the decision problem can be found in constant time.  相似文献   
998.
We show that for some special functions (called k-multigrid equidistributed functions), we can compute the limit of the frequency of patterns in the discretization of their graph, when the resolution tends to zero. This result is applied to parabolas. We deduce also that local length estimators almost never converge to the length for the parabolas.  相似文献   
999.
基于射频系统芯片nRF24LE1,设计了一种具有双向通信功能的汽车遥控器和车锁控制系统,重点研究了系统的结构和软、硬件设计。遥控器不仅可以发送控制信息,还可以接收车锁的反馈信息,比目前普遍使用的单向遥控器功能强大。同时在车锁部分,增加了GSM模块,实现GSM网络与遥控器的双重控制,更能确保汽车的安全。  相似文献   
1000.
跌倒检测在远程健康监管系统中的应用研究   总被引:1,自引:0,他引:1  
利用三轴加速度传感器对人体活动产生的加速度信号进行采集,提出了将数据分析分割成用户终端信号的预处理和在后台处理两部分。在用户终端采取基于1-class SVM分类算法对疑似数据进行提取,在后台通过分析不同动作事件下其能量损耗的阈值范围的不同进行跌倒判断,并分析了人体在特定时域的速度、位移以及倾角作为判断跌倒的辅助判据。实验表明,该应用能够为老年人的健康提供一种新的保障。  相似文献   
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