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排序方式: 共有702条查询结果,搜索用时 15 毫秒
1.
2.
An environmental factor converts reliability test results at one environmental condition into equivalent “failure” information at other environments. This paper studies environmental-factor estimation for the binomial distribution. Under general conditions, Bayes point estimates and credibility limits for environmental factors are derived. Classical point and confidence interval estimates are introduced and compared with the Bayes estimators. The characteristics of Bayes and classical estimators for the binomial distribution are summarized through numerical computation and theoretical analysis. A numerical example of reliability assessment by means of environmental factors is presented 相似文献
3.
Fretting fatigue is one of the most important phenomena for inducing a significant reduction of fatigue strength and consequently,
leading to unexpected failure accidents of the engineering structures even at very low stresses. In the present study, both
plain and fretting fatigue tests with zero mean stress were carried out on two different types of steel, low-carbon steel
and martensitic stainless steel, by means of a reversed bending fatigue testing machine. The drop in the fatigue strengths
through fretting at vise clamp-specimen interface were significant for both tested steels. The fretting processes produced
a reduction in fatigue strength of about 27% for low-carbon steel and 16% for martensitic stainless steel. 相似文献
4.
Over the last few decades, many different evolutionary algorithms have been introduced for solving constrained optimization problems. However, due to the variability of problem characteristics, no single algorithm performs consistently over a range of problems. In this paper, instead of introducing another such algorithm, we propose an evolutionary framework that utilizes existing knowledge to make logical changes for better performance. The algorithmic aspects considered here are: the way of using search operators, dealing with feasibility, setting parameters, and refining solutions. The combined impact of such modifications is significant as has been shown by solving two sets of test problems: (i) a set of 24 test problems that were used for the CEC2006 constrained optimization competition and (ii) a second set of 36 test instances introduced for the CEC2010 constrained optimization competition. The results demonstrate that the proposed algorithm shows better performance in comparison to the state-of-the-art algorithms. 相似文献
5.
S. E. Afifi A. A. Elsayed A. E. Elsherief 《JOM Journal of the Minerals, Metals and Materials Society》1987,39(2):38-41
This paper reports on the mode of action of two different organic additives—gelatine and thiourea—during the electrorefining of copper from acid copper sulfate solutions. Gelatine increases the cathode current efficiency and produces smoother deposits up to a certain level of concentration, beyond which, however, these effects are diminished by the steric hinderance of bulky molecular entities adsorbed to the electrode surface. Thiourea decreases the cathode current efficiency when present at concentrations around 5 mg/1. Nonetheless, it improves deposit quality. In higher concentrations, thiourea increases the cathodic current efficiency but also promotes nodule formation and rough deposits. The degradation and/or hydrolysis of both additives and the various interactions with the electrode surface and with cupric ions in solution are also examined. 相似文献
6.
Ikram Muhammad Jawad Saleh Mostafa Elsayed Al-Hashimi Muhammad Abdulhamid Abulnaja Osama Ahmed 《The Journal of supercomputing》2022,78(13):14919-14939
The Journal of Supercomputing - Power consumption is likely to remain a significant concern for exascale performance in the foreseeable future. In addition, graphics processing units (GPUs) have... 相似文献
7.
Zainal Abidin Ali Muhammad Aidil Roslan Rosiyah Yahya Wan Yusoff Wan Sulaiman Rustam Puteh 《IET nanobiotechnology / IET》2017,11(2):152
In this study, larvicidal activity of silver nanoparticles (AgNPs) synthesised using apple extract against fourth instar larvae of Aedes aegypti was determined. As a result, the AgNPs showed moderate larvicidal effects against Ae. aegypti larvae (LC50 = 15.76 ppm and LC90 = 27.7 ppm). In addition, comparison of larvicidal activity performance of AgNPs at high concentration prepared using two different methods showed that Ae. aegypti larvae was fully eliminated within the duration of 2.5 h. From X‐ray diffraction, the AgNP crystallites were found to exhibit face centred cubic structure. The average size of these AgNPs as estimated by particle size distribution was in the range of 50–120 nm. The absorption maxima of the synthesised Ag showed characteristic Ag surface plasmon resonance peak. This green synthesis provides an economic, eco‐friendly and clean synthesis route to Ag.Inspec keywords: silver, nanofabrication, X‐ray diffraction, zoology, particle size, nanoparticles, biomedical materials, nanomedicineOther keywords: time 2.5 h, size 50 nm to 120 nm, silver nanoparticle, larvicidal property, instar larvae, Aedes aegypti, larvicidal effect, larvicidal activity performance, X‐ray diffraction, nanoparticle particle size distribution, absorption maxima, silver surface plasmon resonance peak 相似文献
8.
Ahmed Abdu Alattab Mohammed Eid Ibrahim Reyazur Rashid Irshad Anwar Ali Yahya Amin A. Al-Awady 《计算机、材料和连续体(英文)》2023,74(2):2397-2412
This research proposes a machine learning approach using fuzzy logic to build an information retrieval system for the next crop rotation. In case-based reasoning systems, case representation is critical, and thus, researchers have thoroughly investigated textual, attribute-value pair, and ontological representations. As big databases result in slow case retrieval, this research suggests a fast case retrieval strategy based on an associated representation, so that, cases are interrelated in both either similar or dissimilar cases. As soon as a new case is recorded, it is compared to prior data to find a relative match. The proposed method is worked on the number of cases and retrieval accuracy between the related case representation and conventional approaches. Hierarchical Long Short-Term Memory (HLSTM) is used to evaluate the efficiency, similarity of the models, and fuzzy rules are applied to predict the environmental condition and soil quality during a particular time of the year. Based on the results, the proposed approaches allows for rapid case retrieval with high accuracy. 相似文献
9.
大量的研究行为识别方法集中在检测简单的动作,如:步行,慢跑或者跳跃等;针对于打斗或者动作复杂的攻击性行为则研究较少;而这些研究在某些监控场景下非常有用,如:监狱,自助银行,商场等. 传统的暴力行为识别研究方法主要利用先验知识来手动设计特征,而本文提出了一种基于3D-CNN结构的暴力检测方法,通过三维深度神经网络直接对输入进行操作,能够很好的提取暴力行为的时空特征信息,从而进行检测. 从实验结果可以看出,本文方法能较好地识别出暴力行为,准确率要高于人工设计特征的方法. 相似文献
10.
SATCHMORE was introduced as a mechanism to integrate relevancy testing with the model-generation theorem prover SATCHMO. This
made it possible to avoid invoking some clauses that appear in no refutation, which was a major drawback of the SATCHMO approach.
SATCHMORE relevancy, however, is driven by the entire set of negative clauses and no distinction is accorded to the query
negation. Under unfavorable circumstances, such as in the presence of large amounts of negative data, this can reduce the
efficiency of SATCHMORE. In this paper we introduce a further refinement of SATCHMO called SATCHMOREBID: SATCHMORE with BIDirectional
relevancy. SATCHMOREBID uses only the negation of the query for relevancy determination at the start. Other negative clauses
are introduced on demand and only if a refutation is not possible using the current set of negative clauses. The search for
the relevant negative clauses is performed in a forward chaining mode as opposed to relevancy propagation in SATCHMORE which
is based on backward chaining. SATCHMOREBID is shown to be refutationally sound and complete. Experiments on a prototype SATCHMOREBID
implementation point to its potential to enhance the efficiency of the query answering process in disjunctive databases.
Donald Loveland, Ph.D.: He is Emeritus Professor of Computer Science at Duke University. He received his Ph.D. in mathematics from New York University
and taught at NYU and CMU prior to joining Duke in 1973. His research in automated deduction includes defining the model elimination
proof procedure and the notion of linear resolution. He is author of one book and editor/co-editor of two other books on automated
theorem proving. He has done research in the areas of algorithms, complexity, expert systems and logic programming. He is
an AAAI Fellow, ACM Fellow and winner of the Herbrand Award in Automated Reasoning.
Adnan H. Yahya, Ph.D.: He is an associate professor at the Department of Electrical Engineering, Birzeit University, Palestine. He received his
Diploma and PhD degrees from St. Petersburg Electrotechnical University and Nothwestern University in 1979 and 1984 respectively.
His research interests are in Artificial Intelligence in general and in the areas of Deductive Databases, Logic Programming
and Nonmonotonic Reasoning in particular. He had several visiting appointments at universities and research labs in the US,
Germany, France and the UK. Adnan Yahya is a member of the ACM, IEEE and IEEE Computer Society. 相似文献