检索结果-南通市图书馆

Intrinsic Photoconductivity of Few-layered ZrS2 Phototransistors via Multiterminal Measurements

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Semiconductor Science and Information Devices 2019年第2期1卷 19-28页

作者： Rukshan M.Tanthirige Carlos Garcia Saikat Ghosh Frederick Jackson II Jawnaye Nash Daniel Rosenmann Ralu Divan liliana stan Anirudha V.Sumant Stephen A.McGill Paresh C.ay Nihar R.Pradhan Layered Materials and Device Physics Laboratory Department of ChemistryPhysics and Atmospheric ScienceJackson State UniversityJacksonMS 39217USA National High Magnetic Field Laboratory TallahasseeFL 32310USA Kunming University of Science and Technology Kunming 650500China Center for Nanoscale Materials Argonne National Laboratory9700 S-Cass AvenueLemontIL-60439USA

We report intrinsic photoconductivity studies on one of the least examined layered compounds,***-atomic layer ZrS2 field-effect transistors were fabricated on the Si/SiO2 substrate and photoconductivity measurements were performed using both two-and four-terminal configurations under the illumination of 532 nm laser *** measured photocurrent as a function of the incident optical power at several source-drain(bias)*** observe a significantly large photoconductivity when measured in the multiterminal(four-terminal)configuration compared to that in the two-terminal *** an incident optical power of 90 nW,the estimated photosensitivity and the external quantum efficiency(EQE)measured in two-terminal configuration are 0.5 A/W and 120%,respectively,under a bias voltage of 650 *** the same conditions,the four-terminal measurements result in much higher values for both the photoresponsivity(R)and EQE to 6 A/W and 1400%,*** significant improvement in photoresponsivity and EQE in the four-terminal configuration may have been influenced by the reduction of contact resistance at the metal-semiconductor interface,which greatly impacts the carrier mobility of low conducting *** suggests that photoconductivity measurements performed through the two-terminal configuration in previous studies on ZrS2 and other 2D materials have severely underestimated the true intrinsic properties of transition metal dichalcogenides and their remarkable potential for optoelectronic applications.

关键词： Field-effect transistors Zirconium sulphide Phototransistor Responsivity Quantum efficiency

Reproducibility of deposition and industrial applications of stable superhard nanocomposites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2004年第Z1期14卷 19-24页

作者： stan Veprek Department for Chemistry Technical University Munich Lichtenbergstr. 4 D-85747 Garching b. Munich Germany

After a brief introduction regarding the different approaches to superhard coatings we shall concentrate on the problem of the reproducibility of the deposition of superhard and thermally very stable nanocomposites according to the design principle published by Veprek and Reiprich in 1995. It will be shown that either the choice of inappropriate deposition conditions, in contradiction to our design principle, or impurities in the coatings are the reason for the lack of reproducibility of our earlier results by many other workers. We shall also briefly summarize the recent industrial applications.

关键词： superhard nanocomposite reproducibility of deposition industrial application

OPTIMAL HIERARCHY STRUCTURES FOR MULTI-ATTRIBUTE-CRITERIA DECISIONS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2009年第2期22卷 228-242页

作者： stan LIPOVETSKY GfK Custom Research North America

A problem of a hierarchy structure optimization is *** structures arewidely used in the Analytic Hierarchy Process,conjoint analysis,and various other methods of multiplecriteria decision *** problem consists in finding a structure that needs a minimum number ofpair comparisons for a given total number of the *** an optimal hierarchy,the minimumefforts are needed for eliciting data and synthesizing the local preferences across the hierarchy to getthe global priorities or *** estimation techniques are developed and numerical *** and numerical results suggest optimal ways of priority evaluations for practicalmanagerial decisions in a complex environment.

关键词： Analytic Hierarchy Process conjoint analysis hierarchy optimization pair comparisons.

Existence of Positive Solutions to Semipositone Singular Dirichlet Boundary Value Problems

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2006年第6期22卷 1891-1914页

作者： Svatoslav stan■K Department of Mathematical Analysis Faculty of SciencePalack■University

The paper presents the conditions which guarantee that for some positive value of μ there are positive solutions of the differential equation （Ф（x＇））＇＋μQ（t, x, x＇） = 0 satisfying the Dirichlet boundary conditions x（0） = x（T） = 0. Here Q is a continuous function on the set [0, T] × （0, ∞） ~ （R ／ {0}） of the semipositone type and Q is singular at the value zero of its phase variables.

关键词： existence positive solution semipositone singular problem Dirichlet boundary conditions Ф-Laplacian

A cognitive model＇s view of animal cognition

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2011年第4期57卷 499-513页

作者： Sidney D'MELLO stan FRANKLIN Department of Psychology University of Memphis Memphis TN 38152 USA Institute of Intelligent Systems University of Memphis Memphis TN 38152 USA

Although it is a relatively new field of study, the animal cognition literature is quite extensive and difficult to synthesize. This paper explores the contributions a comprehensive, computational, cognitive model can make toward organizing and assimilating this literature, as well as toward identifying important concepts and their interrelations. Using the LIDA model as an example, a framework is described within which to integrate the diverse research in animal cognition. Such a framework can provide both an ontology of concepts and their relations, and a working model of an animal＇s cognitive processes that can compliment active empirical research. In addition to helping to account for a broad range of cognitive processes, such a model can help to comparatively assess the cognitive capabilities of different animal species. After deriving an ontology for animal cognition from the LIDA model, we apply it to develop the beginnings of a database that maps the cognitive facilities of a variety of animal species. We conclude by discussing future avenues of research, particularly the use of computational models of animal cognition as valuable tools for hypotheses generation and testing [Current Zoology 57 （4）： 499-513, 2011].

关键词： Cognitive models Computational models LIDA Ontology Taxonomy

Express analysis for prioritization:Best-Worst Scaling alteration to System 1

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Management Analytics 2020年第1期7卷 12-27页

作者： stan Lipovetsky Minneapolis MinnesotaUSA

The work considers modification of the Best–Worst Scaling(BWS)to the so-called System 1(S1)approach.S1 was described by *** as a spontaneous and automatic reaction by an unconsciousway in which human decision-makers choose among multiple *** of S1 can be seen as a simplified BWS for data eliciting and express analysis of prioritization between many compared *** S1,a respondent picks the items with which she feels“happy”,and those can be one,several,all,or none items in a *** of utilities is performed by multinomial-logit modeling with different optimization criteria which produce parameters of the models and choice probabilities of the *** examples by marketing research data are encouraging and demonstrating that spontaneous choice decisions can make S1 approach very fast,efficient,and convenient for express analysis of items prioritization,especially for big data.

关键词： System 1 BWS max diff MNLutility choice probability prioritization

High temperature oxidation of inoculated high Si/SiMo ductile cast irons in air and combustion atmospheres

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2024年第5期21卷 555-562页

作者： Iuliana stan Mihai Chisamera Robert Lascu Codrut Cariga Eduard Stefan Stelian stan Denisa Anca Iulian Riposan National University of Science and Technology POLITEHNICA Bucharest Materials Science and Engineering Faculty313 Splaiul IndependenteiSector 6060042 BucharestRomania

The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry air and combustion gas containing water vapour(natural gas burning).The oxidation is influenced by the gas atmosphere type,the iron alloying system,and the inoculating elements depending on the heating *** weight gain increases from 0.001%-0.1%(400°C)to 0.05%-0.70%(600°C)and up to 0.10%-2.15%(800°C).No particular effects of the considered influencing factors are found when heating at 400°C,while at 600°C,mainly the oxidation gas atmosphere type shows a visible *** the highest heating temperature of 800°C,a limited increase of the weight gain is found for dry air atmosphere(up to 0.25%),but it drastically increases for combustion atmospheres(0.65%-2.15%).The water vapour presence in the combustion atmosphere is an important oxidising factor at 600-800°*** alloying system appears to influence the oxidation behavior mainly at a heating temperature of 800°C in the combustion atmosphere,as evidenced by the lower weight gain in 5.25%silicon cast *** effects of inoculating elements increase with the heating temperature,with Ca and Ba-FeSi inoculation generally showing better *** inoculated with CaRE-FeSi exhibit a higher degree of *** results are in good relationship with the previous reported data:Ca-Ba-inoculation system appears to be better than simple Ca for improving the graphite parameters,while RE-bearing inoculant negatively affects the compactness degree of graphite particles in high-Si ductile *** the lower compactness degree is typical for graphite nodules in high-Si ductile irons,which negatively affects the oxidation resistance,it is necessary to employ specific metallurgical treatments to improve nodule ***,in particular,is a potential method to achieve this improvement.

关键词： ductile iron spheroidal graphite Si/SiMo oxidation air/combustion atmospheres FeSiCaMgRE treatment Ca,Ca-Ba,Ca-RE inoculation structure characteristics

Recognition of rock anisotropy using integrated seismic approach-A case in Strzegom and Podlesna,Poland

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1759-1767页

作者： Iwona stan-Kłeczek Artur Marciniak University of Silesia Faculty of Natural SciencesSosnowiecPoland Institute of Geophysics of Polish Academy of Sciences WarsawPoland

This paper presents the integration of seismic refraction and multichannel analysis of surface wave(MASW)measurements to investigate the anisotropy of P-and S-wave ***,synthetic forward modelling is presented as a tool for supporting seismic anisotropy *** geophysical measurements of cracks allowed to recognise the fracturing of a granite rock mass in a Paleozoic granite quarry(Strzegom,Poland)and a dolomite rock mass in a Triassic dolomite quarry(Podlesna,Poland).Application of the forward modelling supports the interpretation of seismic methods,simplifying data processing and verifying the final results based on data from difficult seismic *** a result of direct measurements,two crack systems were determined in granite rock mass:NNE-SSW and NNW-SSE,and two in dolomite rock mass:NNE-SSW and ***,the numerical results show the relationship between the highest values of P-and S-wave velocities and separated crack systems which allowed an unequivocal interpretation of the direction of stress,resulting in the *** obtained information is promising to be helpful in mining exploration for optimising excavation works.

关键词： Fracturing Anisotropy Seismic refraction Multichannel analysis of surface wave(MASW) Forward modelling

Performance of heavy ductile iron castings for windmills

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2010年第2期7卷 163-170页

作者： Iulian Riposan Mihai Chisamera Stelian stan POLITEHNICA University of Bucharest 313 Spl.Independentei RO-060042 BucharestRomania

The main objective of the present paper is to review the specific characteristics and performance obtaining conditions of heavy ductile iron(DI) castings,typically applied in windmills industry,such as hubs and rotor *** requirements for high impact properties in DI at low temperatures are part of the ENGJS-400-18U-LT(SRN 1563) commonly referred to as GGG 40.3(DIN 1693).Pearlitic in-uence factor(Px) and antinodularising action factor(K1) were found to have an important in-uence on the structure and mechanical properties,as did Mn and P content,rare earth(RE) addition and inoculation *** presence of high purity pig iron in the charge is extremely beneficial,not only to control the complex factors Px and K1,but also to improve the 'metallurgical quality' of the iron melt.A correlation of C and Si limits with section modulus is very important to limit graphite nodule *** and surface-degenerated graphite are the most controlled graphite morphologies in windmills *** paper concluded on the optimum iron chemistry and melting procedure,Mg-alloys and inoculants peculiar systems,as well as on the practical solutions to limit graphite degeneration and to ensure castings of the highest integrity,typically for this field.

关键词： heavy ductile iron castings windmills parts chemistry structure treatments control