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[[abstract]]The authors report results on the application of several bootstrap techniques in estimating the error rate of nearest-neighbor (1-NN) and quadratic classifiers. The conducted experiments show that, in most cases, the confidence interval of a bootstrap estimator of classification error is smaller than that of the leave-one-out estimator. The error of 1-NN, quadratic, and Fisher classifiers are estimated for several real data sets
[[abstract]]In an era of submicron technology, routing is becoming a dominant factor in area, timing and power consumption. The problem of scan flip-flops chaining with the objective of achieving minimum routing area overhead is studied. The first attempt is to chain the flip-flops at the logic level. To make more accurate decisions on chaining flip-flops, the second attempt is to perform the chaining of scan flip-flops taking layout information into consideration. Specifically, the authors show that the chaining problem is a travelling salesman problem (TSP). Then, two heuristics, greedy and matching-based algorithms, are proposed to solve the TSP problem. Various cost functions are defined which take layout information into account. Benchmarking results show that the cost function achieves the best results when it considers placement...
[[abstract]]Automated validation techniques for verifying large scale software systems have been effectively used to improve their reliability. One aspect of these validation is to statically analyze a program without resorting to actual execution. This paper discusses and presents some techniques to validate the control flow structure of programs without regarding their semantic meanings. Techniques developed in graph theory are used to validate control flow structure. Reachability concept of directed graphs is used to validate the well-formation of programs and locate possible structural flaws, such as redundant codes, loops without exit, both in module level and system level. The notion of structural correctness is defined. Correctness validation through isomorphism checking of directed graphs is discussed and an augmented algorithm...
[[abstract]]Traditionally, the Byzantine agreement (BA) problem has been studied either in a fully connected network or in a broadcast network. Here, a generalized network model for BA is proposed. The conventional fully connected network or broadcast network is a special case of the new network architecture. A BA problem with the processor in a malicious fault is studied in the model. The proposed protocol incorporates the previous protocols developed for a fully connected network or a broadcast network, solves a BA problem by using the minimum number of rounds, and can tolerate the maximum number of faulty processors.
[[abstract]]A new photovoltaic material, CuInS2 has been investigated. Mainly due to its direct band gap of 1.5 eV, CuInS2 promises to offer high conversion efficiency as a solar cell. Single crystals are grown by chemical vapor transport. Theoretical calculations and experiments were carried out in order to determine the optimum growth conditions, and later similar calculations were done for heterojunction epitaxial layers. Since properties of CuInS2 are not well known, doping and annealing effects were studied, and methods to determine CuInS2 composition and its impurity contents were developed. Low cost arrays may be constructed in two ways. One way is by employing both RF sputtering and flash evaporation methods. Another way is by tandem cells of very high efficiency to be coupled with concentrators.
An actual cultural-heritage-related problem is how to effectively manage the global distribution of digitized cultural and scientific information, taking into account that such a global distribution is only doable through the Internet. Hence, adequately designing software applications realizing brokerage functionality in the global space, particularly concerning digitized cultural/scientific information, is to be considered as an essential cultural-heritage-related task. However, due to its great complexity, the usage of the existing popular modelling instrumentarium seems insufficiently useful; this is mainly because the realization of a satisfactory cultural-heritage brokering requires a deep understanding and consideration of the original business reality. Inspired by this challenge, we have aimed at exploring relevant strengths of ...
[[abstract]]A new technique, namely organometallic chemical vapor deposition (OMCVD), has been developed in the fabrication of Cu2S/CdS solar cells. This new method can provide good interface of heterojunctions and can give a better control over the Cu2S stoichiometry, and it can also provide precise control of the doping level and type of dopants, which aims at increasing the diffusion length in Cu2S. This method involves processes of producing [CuCl(NCCH3)]n and H2S and their reaction to form CuxS. The authors focus on the preparation of CuxS films by OMCVD method. Various characterization techniques such as AA, NAA, EDAX, RBS and X-ray analyses were developed to understand the fundamental mechanism of the CVD growth.
In this paper we propose a fast adaptive importance sampling method for the efficient simulation of buffer overflow probabilities in queueing networks. The method comprises three stages. First we estimate the minimum cross-entropy tilting parameter for a small buffer level; next, we use this as a starting value for the estimation of the optimal tilting parameter for the actual (large) buffer level; finally, the tilting parameter just found is used to estimate the overflow probability of interest. We recognize three distinct properties of the method which together explain why the method works well; we conjecture that they hold for quite general queueing networks. Numerical results support this conjecture and demonstrate the high efficiency of the proposed algorithm.
The capability to safely interrupt business process activities is an important requirement for advanced process-aware information systems. Indeed, exceptions stemming from the application environment often appear while one or more application-related process activities are running. Safely interrupting an activity consists of preserving its context, i.e., saving the data associated with this activity. This is important since possible solutions for an exceptional situation are often based on the current data context of the interrupted activity. In this paper, a data classification scheme based on data relevance and on data update frequency is proposed and discussed with respect to two different real-world applications. Taking into account this classification, a correctness criterion for interrupting running activities while preserving th...
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