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High Voltage 2019年第3期4卷 186-196页

作者： Panagiotis A.Karafotis Pavlos s.Georgilakis National Technical University of Athens(NTUA) School of Electrical and Computer Engineering9 Iroon Polytechniou StreetAthensGreece

The purpose of this paper is twofold:(i)to propose a methodology to accurately evaluate power quality indices,and(ii)to highlight the importance of power quality monitoring services at different voltage levels of three-phase power *** proposed methodology is based on wavelet packet transform(WPT)and is able to perform power quality analysis in three-phase power systems operating under stationary and non-stationary conditions,in the presence of both harmonics and *** test cases are examined:synthetic voltage and current waveforms including noise,simulated test systems,a modified IEEE 13-bus test feeder,as well as experimental *** obtained results in all cases demonstrate the accuracy and the effectiveness of the proposed WPT method and its superiority over fast Fourier transform to accurately evaluate power quality indices in case of non-stationary disturbances.

关键词： power stationary transform

Gamma-Ray Bursts: Afterglows and Central Engines

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Chinese Journal of Astronomy and Astrophysics 2001年第1期1卷 1-20页

作者： K.s.Cheng T.Lu DepartmentofPhysics UniversityofHongKongPokfulamRoadHongKong DepartmentofAstronomy NanjingUniversit

Gamma-ray bursts (GRBs) are the most intense transient gamma-ray events in the sky; this, together with the strong evidence (the isotropic and inhomogeneous distribution of GRBs detected by BAsTE) that they are located at cosmological distances, makes them the most energetic events ever known. For example, the observed radiation energies of some GRBs are equivalent to the total convertion into radiation of the mass energy of more than one solar mass. This is thousand times stronger than the energy of a supernova explosion. some unconventional energy mechanism and extremely high conversion efficiency for these mysterious events are required. The discovery of host galaxies and association with supernovae at cosmological distances by the recently launched satellite of BepposAX and ground based radio and optical telescopes in GRB afterglow provides further support to the cosmological origin of GRBs and put strong constraints on their central engine. It is the aim of this article to review the possible central engines, energy mechanisms, dynamical and spectral evolution of GRBs, especially focusing on the afterglows in multi-wavebands.

关键词： gamma-rays: bursts - shock waves - IsM: jets and outflows- radiation mechanisms: non-thermal

Charged analogue of well behaved neutral spheres:an algorithmic approach

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Chinese Physics C 2016年第4期40卷 34-42页

作者： s.Thirukkanesh F.C.Ragel Department of Mathematics Eastern UniversityChenkalady Sri Lanka Department of Physics Eastern UniversityChenkalady Sri Lanka

We establish a systematic algorithmic approach that generates new classes of solutions to the EinsteinMaxwell system in static spherically symmetric spacetime from well known uncharged solutions. A particular case is shown to satisfy all major physical features of a realistic charged star including the standard point-wise energy conditions of normal matter. The solution matches smoothly with the exterior Reissner-Nordstr¨om metric at the pressure free interface. The study, which is reported for a particular choice of gravitational potential, encourages similar approaches to study electrification of well known physically realistic uncharged models.

关键词： behaved realistic spheres matches symmetric smoothly satisfy exterior interior analogue

Role of the intrinsic charm content of the nucleon from various light-cone models on γ + c-jet production

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Chinese Physics C 2016年第12期40卷 37-45页

作者： s.Rostami Muhammad Goharipour Alireza Aleedaneshvar Faculty of Physics Semnan University

Having a precise knowledge of the charm quark component can lead to a better understanding of the fundamental structure of the nucleon. Furthermore, the charm quark distribution function plays an important role in the study of many processes which are sensitive to the charm quark content of the nucleon. In the standard global analysis of patton distribution functions （PDFs）, the charm quark distribution arises perturbatively through the splitting of the gluon into charm-anticharm pairs in the DGLAP evolution equations. Nevertheless, the existence of nonperturbative intrinsic charm quarks in the proton has also been predicted by QCD. In this paper, we study some phenomenological models within the light-cone framework to predict the nonperturbative intrinsic charm quark content of the nucleon. We investigate the impact of these models on the prediction ofγ-＋ c-jet production in pp collisions at the LHC and compare our results on pp→γ, ＋ c-jet with the experimental data of DO.

关键词： heavy quark PDFs intrinsic charm photon production collider phenomenology

Biostratigraphy and palaeoenvironment of deposition of Nsukka Formation,Anambra Basin,southeastern Nigeria

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Journal of Palaeogeography 2017年第1期6卷 45-59页

作者： s.A.Bankole A.O.Ola-Buraimo Department of Chemical and Geological sciences Al-Hikmah UniversityllorinNigeria Department of Geology Federal UniversityBimin KebbiNigeria

Biostratigraphy investigation of Nsukka Formation was carried out by subjecting weLt cutting samples obtained from Nzam-1 weLL to patynotogicat studies with the view towards determining the relative geologic age and pataeoenvironment of deposition of the sediments. sampLes were treated in the Laboratory through digestion with hydrofluoric acid, sieving with 5 μm, oxidation with Nitric acid and mounting of the sLides into sections with DPX mountant. A fairLy high abundance and diversity of miospores were recovered, white the interval （847-1372 m） contains distinctive and diagnostic patynomorphs which are stratigraphicatty important. A spinizonocolpites baculatus assemblage zone was established based on the basal occurrence of s. baculatus, spinizonocolpites echinatus, Constructipollenites ineffectus, Periretisyncolpites sp. Periretisyncolpites giganteus, Monocolpites sp 1, Foveotriletes margaritae, syncolporites marginatus, and Longapertites marginatus. The upper part of the intervat is marked by association of Anacolosidites luidonisis （at top）, Mauritiidites crassibaculatus, Retistephanocolpites williamsi, Proteacidites dehaani, Echitriporites trianguliformis, Proxapertites cursus, Retidiporites magdalenensis, s. baculatus, Retitricolpites gigeonetti, F. margaritae and Araucariadtes sp. The Nsukka Formation is dated as Late Maastrichtian based on the cooccurrence of recovered index fossits. Importantly, Cretaceous-Tertiary （K/T） boundary is marked by high fossil content in the Maastrichtian sediments compared to paucity in patynomorph that characterises the overtying Pateocene facies. Pataeoenvironment of the anatyzed section varies atternatety from marginaL marine to continental setting based on the presence of land-derived miospores and dinoflagettates.

关键词： Biostratigraphy Palaeoenvironment Assemblage Gonyaulacacean/Peridinacean ratio Index fossil Anambra Basin

Limsup Results and LIL for Partial sum Processes of a Gaussian Random Field

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Acta Mathematica sinica,English series 2008年第9期24卷 1497-1506页

作者： Yong-Kab CHOI Mikls CsRG Department of Mathematics and RINs Gyeongsang National University Jinju 660-701 Republic of Korea school of Mathematics and statistics Carleton University 1125 Colonel By DriveOttawa K1S 5B6 Canada

Let {ξ j ; j ∈ ℤ+ d be a centered stationary Gaussian random field, where ℤ+ d is the d-dimensional lattice of all points in d-dimensional Euclidean space ℝd, having nonnegative integer coordinates. For each j = (j ... 详细信息

Let {ξsUB> j sUB>; j ∈ ℤsUB>+sUB>sUP> d sUP>be a centered stationary Gaussian random field, where ℤsUB>+sUB>sUP> d sUP>is the d-dimensional lattice of all points in d-dimensional Euclidean space ℝsUP>dsUP>, having nonnegative integer coordinates. For each j = (j sUB>1 sUB>, ..., jd) in ℤsUB>+sUB>sUP> d sUP>, we denote |j| = j sUB>1 sUB>... j sUB>d sUB>and for m, n ∈ ℤsUB>+sUB>sUP> d sUP>, define s(m, n] = ΣsUB> msUB>ζsUB> j sUB>, σsUP>2sUP>(|n−m|) = Es sUP>2 sUP>(m, n], s sUB>n sUB>= s(0, n] and s sUB>0 sUB>= 0. Assume that σ(|n|) can be extended to a continuous function σ(t) of t > 0, which is nondecreasing and regularly varying with exponent α at b ≥ 0 for some 0 some additional conditions, we study limsup results for increments of partial sum processes and prove as well the law of the iterated logarithm for such partial sum processes.

关键词： stationary Gaussian random field regularly varying function large deviation probability law of the iterated logarithm

Geochemistry of Kestelek Colemanite Deposit, Bursa, Turkey

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Journal of Earth science 2017年第1期28卷 63-77页

作者： sükrü Koc Ozge Kavrazh ismail Kocak Faculty of Department of Geological Engineering Ankara University Ankara 06100 Turkey Graduate school of Natural and Applied sciences Ankara University Ankara 06100 Turkey Department of Geological Engineering Bozok University Yozgat 66100 Turkey

The Kestelek borate deposit has been the subject of geological and mineralogical research over the last decades, but major and trace element geochemistry of this deposit was first investigated in the present study. A total of 22 samples collected from surface exposures and different depths of deposit in boreholes（e.g., lower, middle and upper） comprise the material of this study. Major, trace and REE element analyses of samples were conducted with ICP-Ms and ICP-Es methods. The Kestelek borate deposit of Miocene age was formed in playa lakes in an intermountain closed basin which was developed in volcanically and seismically active areas associated with growth faults and grabens affected the whole Anatolia at the beginning of Paleogene. Only colemanite was found as the borate mineral accompanied in lesser amount by calcite, aragonite, smectite, illite, chlorite, corrensite, heulandite and quartz. In colemanite samples, all major elements, except for Ca, show depletion trends with respect to average of earth crust and andesite. For the trace elements, Li, Cs, sb, As, sr and se are characterized by significantly high concentrations. Evaluation of element concentrations and geochemical characteristics reveal that As, Cs, sb and Li are of detrital origin, se together with B and Ca are of non-detrital and sr is indicative of both detrital and non-detrital origin. REE distributions indicate that at least two different depositional regimes prevail in the environment. Corrensite, a clay mineral forming in lake waters, is derived from volcanism. Negative Ce and positive Eu anomalies are indicative of contribution from hydrothermal solutions and fluids.

关键词： borate mineralogy geochemistry REE Kestelek Turkey.

A data-driven approach to π^0,η and η＇ single and double Dalitz decays

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Chinese Physics C 2018年第2期42卷 89-105页

作者： Rafel Escribano sergi Gonzàlez-solís Crup de Fisica Tebrica Departament de Fisica Universitat Autbnoma de Barcelona E-08193 Bellaterra (Barcelona) Spain Institut de Fisica d'Altes Energies (IFAE) The Barcelona Institute of Science and Technology (BIST) Campus UAB E-08193 Bellaterra (Barcelona) Spain CAs Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China

The dilepton invariant mass spectra and integrated branching ratios of the single and double Dalitz decays P→l^＋l^-γ and P→l^＋l^-l^＋l^-（P=π^0,η,η＇;l=e or μ） are predicted by means of a data-driven approach based on the use of rational approximants applied to π^0,η and η＇ transition form factor experimental data in the space-like region.

关键词： electromagnetic processes and properties phenomenological models transition form factor

Acrylamide: the new dilemma in food safety

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中国药理学与毒理学杂志 2006年第3期20卷 164-165页

作者： s sRIANUJATA Institute of Nutrition Mahidol University salaya Putthamonthon Nakhonpathom 73170 Thailand

Acrylamide has been brought to the world attention in 2002 with the information that it was found contaminated in many heat treated carbohydrate rich foods. This creates a lot of concern worldwide since the appearance of Aflatoxins many decades ago. The dilemma occurs as the heat treated carbohydrate rich foods are being consumed by population around the world while the high in complex carbohydrate diet is being promoted by international organizations as FAO and WHO in the effort for the prevention of some chronic diseases.

关键词： dilemma coffee developmental

An Intelligent Gestational Diabetes Diagnosis Model Using Deep stacked Autoencoder

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Computers, Materials & Continua 2021年第12期69卷 3109-3126页

作者： A.sumathi s.Meganathan BVijila Ravisankar sRC SASTRA Deemed to be UniversityKumbakonamTamil Nadu612001India Consultant Obstetrician and Gynecologist Anbu Hospital and Nalam ClinicKumbakonamTamil Nadu612001India

Gestational Diabetes Mellitus(GDM)is one of the commonly occurring diseases among women during *** Glucose Tolerance Test(OGTT)is followed universally in the diagnosis of GDM diagnosis at early pregnancy which is costly and ***,there is a need to design an effective and automated GDM diagnosis and classification *** recent developments in the field of Deep Learning(DL)are useful in diagnosing different *** this view,the current research article presents a new outlier detection with deep-stacked Autoencoder(OD-DsAE)model for GDM diagnosis and *** goal of the proposed OD-DsAE model is to find out those mothers with high risks and make them undergo earlier diagnosis,monitoring,and treatment compared to low-risk *** presented ODDsAE model involves three major processes namely,preprocessing,outlier detection,and *** the first step i.e.,data preprocessing,there exists three stages namely,format conversion,class labelling,and missing value replacement using k-nearest neighbors(KNN)*** are superior values which considerably varies from other data ***,it might represent the variability in measurement,experimental errors or novelty ***,Hierarchical Clustering(HC)-based outlier detection technique is incorporated in OD-DsAE model,and thereby classification performance can be *** proposed model was simulated using Python 3.6.5 on a dataset collected by the researcher themselves.A series of experiments was conducted and the results were investigated under different *** experimental outcomes inferred that the OD-DsAE model has outperformed the compared methods and achieved high precision of 96.17%,recall of 98.69%,specificity of 89.50%,accuracy of 96.18%,and F-score of 97.41%.

关键词： Gestational diabetes mellitus data classification outlier detection deep learning hierarchical clustering