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排序方式: 共有5775条查询结果,搜索用时 31 毫秒
131.
Muhammad Faisal Michael B. C. Khoo Ayesha Nayab Raja Fawad Zafar 《Quality and Reliability Engineering International》2023,39(1):472-477
Link relative-based approach was used in an article (see reference 1) to enhance the performance of the cumulative sum (CUSUM) control chart. This technique involves the use of firstly, the link relative variable to convert the process observations in a relative to the mean form and secondly, optimal constants to define a new variable which is used as the plotting statistic of the link relative CUSUM chart. In this article, it is proven through simulation study that the optimal constants with fixed values, as reported in the aforementioned article, give different results. Instead, if the regression technique is used, then the same results will be obtained. 相似文献
132.
The alkylamines and their related boron derivatives demonstrated potent cytotoxicity against the growth of murine and human tissue cultured cells. These agents did not necessarily require the boron atom to possess potent cytotoxic action in certain tumor lines. Their ability to suppress tumor cell growth was based on their inhibition of DNA and protein syntheses. DNA synthesis was reduced because purine synthesis was blocked at the enzyme site of IMP dehydrogenase by the agents. In addition ribonucleotide reductase and nucleoside kinase activities were reduced by the agents which would account for the reduced d[NTP] pools. The DNA template or molecule may be a target of the drugs with regard to binding of the drug to nucleoside bases or intercalaction of the drug between DNA base pairs. Only some Of the agents caused DNA fragmentation with reduced DNA viscosity. These effects would contribute to overall cell death afforded by the agents. 相似文献
133.
Coordinated controller tuning of the boiler turbine unit is a challenging task due to the nonlinear and coupling characteristics
of the system. In this paper, a new variant of binary particle swarm optimization (PSO) algorithm, called probability based
binary PSO (PBPSO), is presented to tune the parameters of a coordinated controller. The simulation results show that PBPSO
can effectively optimize the control parameters and achieves better control performance than those based on standard discrete
binary PSO, modified binary PSO, and standard continuous PSO. 相似文献
134.
This paper investigates the unique pharyngeal and uvular consonants of Arabic from the point of view of automatic speech recognition (ASR). Comparisons of the recognition error rates for these phonemes are analyzed in five experiments that involve different combinations of native and non-native Arabic speakers. The most three confusing consonants for every investigated consonant are discussed. All experiments use the Hidden Markov Model Toolkit (HTK) and the Language Data Consortium (LDC) WestPoint Modern Standard Arabic (MSA) database. Results confirm that these Arabic distinct consonants are a major source of difficulty for Arabic ASR. While the recognition rate for certain of these unique consonants such as // can drop below 35% when uttered by non-native speakers, there is advantage to include non-native speakers in ASR. Besides, regional differences in pronunciation of MSA by native Arabic speakers require the attention of Arabic ASR research. 相似文献
135.
Asif Iqbal Naeem U. Dar Ning He Muhammad M. I. Hammouda Liang Li 《Journal of Intelligent Manufacturing》2010,21(6):761-776
The foremost challenge faced by expert systems, for their applicability to real world problems, is their inherent deficiency
of dynamism. For an expert system to be more pragmatic and applicable, the whole structure of an expert system—including rule-base,
fuzzy sets, and even user-interface—needs to be upgraded continuously. This continuous up gradation demands full-time, repetitive,
and cumbersome involvement of knowledge engineers. Machine learning is an answer to this problem, but unfortunately, the solutions
that have been provided are limited in scope. For example, most of the researchers put forward techniques of either generating
just rules from data, or self-expanding and self-correcting knowledge-base only. The innovative approach presented in this
paper is broader in scope. It enhances the efficacy and viability of expert systems to be more capable of coping with dynamic
and ever-changing industrial environments. The objective is facilitated by rendering, concurrently, the self-learning, self-correcting,
and self-expanding abilities to the expert system, without requiring knowledge engineering skills of the developers. This
means that the user needs just to feed data in form of the values of input/output variables and the complete development of
expert system is done automatically. The superiority of the proposed expert system, regarding its continuous self-development,
has been explained with the help of three examples related to prediction and optimization of milling and welding processes. 相似文献
136.
Ling-Yuan Hsu Shi-Jinn Horng Pingzhi Fan Muhammad Khurram Khan Yuh-Rau Wang Ray-Shine Run Jui-Lin Lai Rong-Jian Chen 《Expert systems with applications》2011,38(5):5525-5531
In this paper, we proposed a modified turbulent particle swarm optimization (named MTPSO) model for solving planar graph coloring problem based on particle swarm optimization. The proposed model is consisting of the walking one strategy, assessment strategy and turbulent strategy. The proposed MTPSO model can solve the planar graph coloring problem using four-colors more efficiently and accurately. Compared to the results shown in Cui et al. (2008), not only the experimental results of the proposed model can get smaller average iterations but can get higher correction coloring rate when the number of nodes is greater than 30. 相似文献
137.
Robots have played an important role in the automation of computer aided manufacturing. The classical robot control implementation involves an expensive key step of model-based programming. An intuitive way to reduce this expensive exercise is to replace programming with machine learning of robot actions from demonstration where a (learner) robot learns an action by observing a demonstrator robot performing the same. To achieve this learning from demonstration (LFD) different machine learning techniques such as Artificial Neural Networks (ANN), Genetic Algorithms, Hidden Markov Models, Support Vector Machines, etc. can be used. This piece of work focuses exclusively on ANNs. Since ANNs have many standard architectural variations divided into two basic computational categories namely the recurrent networks and feed-forward networks, representative networks from each have been selected for study, i.e. Feed Forward Multilayer Perceptron (FF) network for feed-forward networks category and Elman (EL), and Nonlinear Autoregressive Exogenous Model (NARX) networks for the recurrent networks category. The main objective of this work is to identify the most suitable neural architecture for application of LFD in learning different robot actions. The sensor and actuator streams of demonstrated action are used as training data for ANN learning. Consequently, the learning capability is measured by comparing the error between demonstrator and corresponding learner streams. To achieve fairness in comparison three steps have been taken. First, Dynamic Time Warping is used to measure the error between demonstrator and learner streams, which gives resilience against translation in time. Second, comparison statistics are drawn between the best, instead of weight-equal, configurations of competing architectures so that learning capability of any architecture is not forced handicap. Third, each configuration's error is calculated as the average of ten trials of all possible learning sequences with random weight initialization so that the error value is independent of a particular sequence of learning or a particular set of initial weights. Six experiments are conducted to get a performance pattern of each architecture. In each experiment, a total of nine different robot actions were tested. Error statistics thus obtained have shown that NARX architecture is most suitable for this learning problem whereas Elman architecture has shown the worst suitability. Interestingly the computationally lesser MLP gives much lower and slightly higher error statistics compared to the computationally superior Elman and NARX neural architectures, respectively. 相似文献
138.
In this paper, we introduce and consider a new class of mixed variational inequalities involving four operators, which are called extended general mixed variational inequalities. Using the resolvent operator technique, we establish the equivalence between the extended general mixed variational inequalities and fixed point problems as well as resolvent equations. We use this alternative equivalent formulation to suggest and analyze some iterative methods for solving general mixed variational inequalities. We study the convergence criteria for the suggested iterative methods under suitable conditions. Our methods of proof are very simple as compared with other techniques. The results proved in this paper may be viewed as refinements and important generalizations of the previous known results. 相似文献
139.
140.
Wilkerson Chris Gao Hongliang Alameldeen Alaa R. Chishti Zeshan Khellah Muhammad Lu Shih-Lien 《Micro, IEEE》2009,29(1):96-103
Two proposed techniques let microprocessors operate at low voltages despite high memory-cell failure rates. They identify and disable defective portions of the cache at two granularities: individual words or pairs of bits. Both techniques use the entire cache during high-voltage operation while sacrificing cache capacity during low-voltage operation to reduce the minimum voltage below 500 mV. 相似文献