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Knowledge modeling based on interval-valued fuzzy rough set and similarity inference: prediction of welding distortion

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第8期15卷 636-650页

作者： zhi-qiang FENG Cun-gen LIU hu huANG Maritime College Qinzhou University State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University

Knowledge-based modeling is a trend in complex system modeling technology. To extract the process knowledge from an information system, an approach of knowledge modeling based on interval-valued fuzzy rough set is presented in this paper, in which attribute reduction is a key to obtain the simplified knowledge model. Through defining dependency and inclusion functions, algorithms for attribute reduction and rule extraction are obtained. The approximation inference plays an important role in the development of the fuzzy system. To improve the inference mechanism, we provide a method of similaritybased inference in an interval-valued fuzzy environment. Combining the conventional compositional rule of inference with similarity based approximate reasoning, an inference result is deduced via rule translation, similarity matching, relation modification, and projection operation. This approach is applied to the problem of predicting welding distortion in marine structures, and the experimental results validate the effectiveness of the proposed methods of knowledge modeling and similarity-based inference.

关键词： Knowledge modeling Interval-valued fuzzy rough set Similarity-based inference Welding distortion prediction

Strong Mixing Subshift of Finite Type and Hausdorff Measure of Its Chaotic Set

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Acta Mathematica Sinica,English Series 2011年第4期27卷 789-798页

作者： Wan Gan SONG zhi hu hua Ming WU School of Mathematical Science Peking University Beijing 100871 P. R. China School of Computer Science and Technology Huaibei Coal Industry Teachers Huaibei 235000 P. R. China School of Mathematical and Computer Science Zhanjiang Teachers College Zhanjiang 524048 P. R. China

We present a sufficient and necessary condition for the subshift of finite type to be a measure-preserving transformation or to be a strong mixing measure-preserving transformation with respect to the Hausdorff measur... 详细信息

关键词： Symbolic space a finite subshift chaotic set Hausdorff measure

On a Nonparametric Estimator for the Finite Time Survival Probability with Zero Initial Surplus

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 739-754页

作者： zhi-min ZHANG Hai-liang YANG hu YANG College of Mathematics and Statistics Chongqing University Department of Statistics and Actuarial Science The University of Hong Kong

In this paper, we consider the estimation of the finite time survival probability in the classical risk model when the initial surplus is zero. We construct a nonparametric estimator by Fourier inversion and kernel density estimation method. Under some mild assumptions imposed on the kernel, bandwidth and claim size density, we derive the order of the bias and variance, and show that the estimator has asymptotic normality property. Some simulation studies show that the estimator performs quite well in the finite sample setting.

关键词： finite time survival probability fourier transform kernel bias variance asymptotic normality

Classification of blocker and non-blocker of hERG potassium ion channel using a support vector machine

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Science China Chemistry 2013年第10期56卷 1413-1423页

作者： XUAN ShouYi LIANG hu WANG zhi YAN AiXia State Key Laboratory of Chemical Resource Engineering Department of Pharmaceutical EngineeringBeijing University of Chemical Technology

The human ether-a-go-go related gene （hERG） channel is responsible for the repolarization during the action potential, and blockage of that may result in severe cardiotoxicity and sudden death. In this study, a dataset containing 1969 compounds was compiled from literature and FDA-approved drugs. Using a support vector machine （SVM）, two groups of computational models were built to distinguish whether a compound is a blocker or non-blocker of hERG potassium ion channel. These mod- els fit generally satisfactory. The 100 models built with MACCS fingerprints （Model Group A） showed an average accuracy of 90% and an average matthews correlation coefficient （MCC） value of 0.77 on the test sets. The 100 models built with selected MOE descriptors （Model Group B） showed an average accuracy of 89% and an average MCC value of 0.74 on the test sets. Molecular hydrophobicity and lipophilicity were found to be very important factors which lead to block the hERG potassium ion channel. Some other molecular properties such as electrostatic properties, features based on van der Waals surface area, the number of rigid bonds and molecular surface rugosity also played important roles in blocking bERG potassium ion channel.

关键词： classification models hERG potassium ion channel MACCS fingerprints MOE descriptors support vector machine(SVM)

Cobalt and manganese stress in the microalga Pavlova viridis (Prymnesiophyceae):Effects on lipid peroxidation and antioxidant enzymes

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Journal of Environmental Sciences 2007年第11期19卷 1330-1335页

作者： LI Mei Zhu Qin hu Chang-wei CHEN Li LIU zhi-li KONG zhi-ming National Key Laboratory of Pollution Control and Resource Reuse of China School of the Environment Nanjing University Nanjing 210093 China School of Life Science Nanjing University Nanjing 210093 China

Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most heavy metals are transported into the marine environment and accumulated without decomposition. The aim of the present study is to investigate the effects on growth, pigments, lipid peroxidation, and some antioxidant enzyme activities of marine microalga Pavlova viridis, in response to elevated concentrations of cobalt （Co） and manganese （Mn）, especially with regard to the involvement of antioxidative defences against heavy metal-induced oxidative stress. In response to Co^2＋, lipid peroxidation was enhanced compared to the control, as an indication of the oxidative damage caused by metal concentration assayed in the microalgal cells but not Mn^2＋. Exposure of Pavlova viridis to the two metals caused changes in enzyme activities in a different manner, depending on the metal assayed： after Co^2＋ treatments, total superoxide dismutase （SOD） activity was irregular, although it was not significantly affected by Mn^2＋ exposure. Co^2＋ and Mn^2＋ stimulated the activities of catalase （CAT） and glutathione （GSH）, whereas, glutathione peroxidase （GPX） showed a remarkable increase in activity in response to Co^2＋ treatments and decreased gradually with Mn^2＋ concentration, up to 50 μmol/L, and then rose very rapidly, reaching to about 38.98% at 200 μmol/L Mn^2＋. These results suggest that an activation of some antioxidant enzymes was enhanced, to counteract the oxidative stress induced by the two metals at higher concentration.

关键词： antioxidant enzymes cobalt manganese malondialdehyde (MDA) Pavlova viridis

Deciphering a Million-Plus RSA Integer with Ultralow Local Field Coefficient h and Coupling Coefficient J of the Ising Model by D-Wave 2000Q

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Tsinghua Science and Technology 2024年第3期29卷 874-882页

作者： Chao Wang Qiaoyun hu Haonan Yao Sumin Wang zhi Pei Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication Shanghai UniversityShanghai 200444China

This work is the first to determine that a real quantum computer(including generalized and specialized)can decipher million-scale RSA relying solely on quantum algorithms,showing the real attack potential of D-Wave *** influence of different column widths on RSA factorization results is studied on the basis of a multiplication table,and the optimal column method is determined by traversal *** traversal experiment of integer factorization within 10000 shows that the local field and coupling coefficients are 75%–93%lower than the research of Shanghai University in 2020 and more than 85%lower than that of Purdue University in *** low Ising model parameters are crucial to reducing the hardware requirements,prompting factoring 1245407 on the D-Wave 2000Q real machine.D-Wave advantage already has more than 5000 qubits and will be expanded to 7000 qubits during 2023–2024,with remarkable improvements in decoherence and *** machine is expected to promote the solution of large-scale combinatorial optimization *** of the contributions of this paper is the discussion of the long-term impact of D-Wave on the development of post-quantum cryptography standards.

关键词： quantum annealing RSA D-Wave 2000Q post-quantum cryptography

Studies on the Voltammetric Behavior of Nicardipine Hydrochloride and its Voltammetric Determination at the Co/GC Modified Electrode

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Chemical Research in Chinese Universities 1999年第2期15卷 36-41页

作者： zhi Yao hu Jingbo LI Qilong huANG Qingquan Department of Chemistry Beijing Normal UniversityBeijing100875 National Institute for the Control of Pharmaceutical and Biological Products Beijing100050

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ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｔｅｃｈｎｉｑｕｅｏｆｉｏｎｉｍｐｌａｎｔａｔｉｏｎｈａｓｂｅｅｎｄｅｖｅｌｏｐｅｄａｓａｍｅａｎｓｏｆｉｎｔｒｏｄｕｃｔｉｎｇｆｏｒｅｉｇｎａｔｏｍｓｉｎｔｏｔｈｅｓｕｒｆａｃｅｌａｙｅｒｓｏｆａｓｏｌｉｄ．Ｔｈｉｓｔ...

关键词： Ion implantation Modified electrode Nicardipine Linearsweep voltammetry

Geochemistry of upper Permian siliceous rocks from the Lower Yangtze region, southeastern China:implications for the origin of chert and Permian ocean chemistry

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Petroleum Science 2019年第2期16卷 252-266页

作者： zhi-Wei Liao Wen-Xuan hu Xiu-Gen Fu Zhong-Ya hu State Key Laboratory of Coal Mine Disaster Dynamics and Control College of Resources and Environmental Science Chongqing University Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Mineral Shandong University of Science and Technology Key Laboratory of Sedimentary Basin and Oil and Gas Resources Ministry of Land and Resources State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of Geology and Palaeontology CAS) State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Institute of Energy Sciences Nanjing University

The Permian Chert Event is of great significance to understanding the geological evolution of the entire Permian; however,the origin of widespread chert formation is debated. We report new geochemical data from deep-marine siliceous rocks of the upper Permian Da-long Formation, Lower Yangtze region, southeastern China. Their geochemical results show that these thin-bedded siliceous rocks have a clear biologic origin, with rare to no evidence of hydrothermal influence. The values of Al/(Al + Fe + Mn) and Eu/Eu~* are 0.60-0.84(mean = 0.72) and 0.45-1.08(mean = 0.77), respectively, and Mn/Ti ratios are relatively low(mean = 0.72). The correlations of LaN/CeN, LaN/YbN, and Fe203/Ti02 with Al_2 O_3/(Al_2 O_3 + Fe_2 O_3), along with the Ce anomaly, indicate that the Da-long siliceous rocks were deposited at a transitional zone between a continental margin and the open ocean; i.e., relatively close to terrestrial sediment input and far from hydrothermal activity. The accumulation of chert is related to its unique paleogeographic location in an equatorial setting with many submarine *** upwelling and frequent local volcanism are the main factors that promoted the development of siliceous rocks in the studied area. Ocean acidification triggered by large-scale volcanism(Large Igneous Province) during the late Permian led to extensive silica precipitation and preservation.

关键词： Lower Yangtze region Da-long Formation Siliceous rock Biological chert Volcanism

Imaging atmospheric turbulence,using entropy to quantify turbulence strength

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Research in Astronomy and Astrophysics 2020年第11期20卷 259-262页

作者： Lu Feng zhi-Xia Shen Jing-Yao hu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Vertical profile of turbulence strength(Cn2)is one of the most important attributes for evaluating a site’s astronomical *** seeing is commonly used for describing turbulence strength,it can only represent the integral of all layers of the turbulence above the *** techniques which can be applied to produce Cn2,such as DIMM-MASS,SCIDAR,etc.,all rely on rather complex systems to do the *** this paper,we present an idea to evaluate the relative strength of turbulence with entropies of short exposure images taken at different conjugated heights of the *** experimental results are also presented in the paper.

关键词： techniques telescope site testing