Wei-Mei Chen

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Queue-mergesort is recently introduced by Golin and Sedgewick as an optimal variant of mergesorts in the worst case. In this paper, we present a complete analysis of the cost distribution of queue-mergesort, including the best, average and variance cases. The asymptotic normality of its cost is also established under the uniform permutation model. We(More)
We give a detailed analysis of the optimization time of the (1 + 1)-Evolutionary Algorithm under two simple fitness functions (OneMax and LeadingOnes). The problem has been approached in the evolutionary algorithm literature in various ways and with different degrees of rigor. Our asymptotic approximations for the mean and the variance represent the(More)
Recently, wireless sensor networks (WSNs) has been widely recognized as a promising technology in latest development in green buildings communications. Localization is one of the fundamental issues in wireless sensor networks. The accuracy of estimated positions can be significantly helpful to use in an intelligent e-applications. In this paper, we propose(More)
We collect major known algorithms in the literature for finding the maxima of multi-dimensional points and provide a simple classification. Several new algorithms are proposed. In particular, we give a new maxima-finding algorithm with expected complexity n + O( √ n logn) when the input is a sequence of points uniformly chosen at random from general planar(More)
Wireless sensor networking is a current topic of research areas and widely used in a variety of applications. The localization of sensor nodes is a fundamental problem in wireless sensor networks. Many localization approaches have been presented and can be implemented using some powerful nodes with GPS devices. In this paper, we introduce a distributed(More)
In this study, we retrospectively reviewed the MRI features of recurrent nasopharyngeal carcinoma (NPC) in 72 patients who underwent MRI before and after gadolinium injection. Recurrent NPC exhibited a high degree of regional spread and a variety of signal intensities and contours. MRI showed a nasopharyngeal mass in 50 patients (69.4 %); other sites of(More)
Simple, two-pahse algorithms are devised for finding the maxima of multidimensional point samples, one of the very first problems studied in computational geometry. The algorithms are easily coded and modified for practical needs. The expected complexity of some measures related to the performance of the algorithms is analyzed. We also compare the(More)
In this paper, we study the upper bounds of memory storage for two different allocators. In the first case, we consider a general allocator that can allocate memory blocks anywhere in the available heap space. In the second case, a more economical allocator constrained by the address-ordered first-fit allocation policy is considered. We derive the upper(More)