Advances in Natural Science最新文献_第4页

Effects of Foundation Models on Jack-up Site Assessment 基础模型对自升式场地评价的影响

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/J.ANS.1715787020120504.688

Z. Jian, Tan Wen-xian, Su Shi-jie, G. Chao

{"title":"Effects of Foundation Models on Jack-up Site Assessment","authors":"Z. Jian, Tan Wen-xian, Su Shi-jie, G. Chao","doi":"10.3968/J.ANS.1715787020120504.688","DOIUrl":"https://doi.org/10.3968/J.ANS.1715787020120504.688","url":null,"abstract":"In order to investigate effects of different foundation models on jack-up site assessment, numerical simulation of a jack-up is presented based on fix joint, pin joint, linear springs and elastic-plastic model. The hull, leg, hull-leg connection is modelled using equivalent beam, beam element, spring element, respectively. Environmental loads, such as steady current, wind, wave, inertial load and buoyancy, are also included in the numerical model. Static and natural frequency extraction analysis of the jack-up is then performed in elevated condition. Finally, static and natural response rules are proposed for the four foundation models. The results show that, the horizontal hull displacement, maximum leg stress, loads on spudcan B and horizontal moment on spudcan A decrease as the rotational stiffness increases, while the natural frequency, vertical load and horizontal load on spudcan A increase with the increasing rotational stiffness. And the responses for elastic-plastic model are close to the pin joint. The proposed modelling and analyzing method is effective and reliable, which could provide guidance for jack-up development and assessment. Key words: Jack-up; Fix joint; Pin joint; Linear springs; Elastic-plastic model; Numerical simulation","PeriodicalId":7348,"journal":{"name":"Advances in Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84632675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Curriculum Reform of C Language Programming and Cultivation of Computational Thinking C语言程序设计课程改革与计算思维的培养

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/6086

Yuxin Zhang, Yan Ding

引用次数: 2

National Spatial Data Infrastructure in Botswana – An Overview 博茨瓦纳国家空间数据基础设施概述

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/J.ANS.1715787020120504.1953

Lopang Maphale, Lucy Phalaagae

{"title":"National Spatial Data Infrastructure in Botswana – An Overview","authors":"Lopang Maphale, Lucy Phalaagae","doi":"10.3968/J.ANS.1715787020120504.1953","DOIUrl":"https://doi.org/10.3968/J.ANS.1715787020120504.1953","url":null,"abstract":"The spatial data plays a vital role in any developmental activities whether it is natural resource management or socio-economi c development. Most land-related government departments in Botswana have over the years since independence in 1966 developed systems to support their principal areas of operations as regards to spatial data. The adequacy and currency of spatial data in government operations improved leading to a need for integrated systems. This has progressively led to issues of building a National Spatial Data Infrastructure (NSDI) and an initiative modeled around Federal Geographic Data Committee (FGDC) has been established. Several facilitative committees were set and several meetings held in attempt to develop the idea to a realizable level and integrate it into the greater workings of the national economy. This noble idea has stalled for some time now and it is the intention of this paper to report on how the idea was initiated in Botswana and look at the probable causes for its stalling. The paper will then go ahead and suggest what could be done to revitalize the idea by relating it to what is considered the best practices in Spatial Data Infrastructure (SDI) programmes globally.","PeriodicalId":7348,"journal":{"name":"Advances in Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79760612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Effect of External Electric Field upon Lower Alkanols 外加电场对低链烷烃的影响

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/J.ANS.1715787020120504.2019

J. Mazurkiewicz, P. Tomasik

{"title":"Effect of External Electric Field upon Lower Alkanols","authors":"J. Mazurkiewicz, P. Tomasik","doi":"10.3968/J.ANS.1715787020120504.2019","DOIUrl":"https://doi.org/10.3968/J.ANS.1715787020120504.2019","url":null,"abstract":"Applying the Monte Carlo method, molecules of methanol, ethanol and 1-butanol are brought to temperature of 300 K and under the influence of external electric field of 0.01 a.u their electronic spectra are simulated with HyperChem 8.0 involving ZINDO/S semiempirical method. Particular molecules differently react to the electric field applied as shown by the electronic spectra simulated in the range of 250-2.84 nm. Total energy of the methanol and ethanol molecules turn slightly more negative in the electric field whereas that energy found for 1-butanol more significantly turn to less negative. HyperChem 8.0 software is used together with the AM1 method for optimization of the conformation of the molecules of methanol, ethanol, 1-propanol and 1-butanol. Then polarizability, charge distribution, potential and dipole moment for molecules placed in the external electric field of 0.000, 0.001, 0.01 and 0.05 a.u. are calculated. External field induces a slightly field strength dependent polarizability of the molecules and the electron density redistribution at particular atoms. Total dipole moment (DM) for particular alkanols increases with the strength of the field applied. There is particularly sharp increase in DM at 0.05 a.u. field. Key words: Butanol; Computer simulations; Ethanol; Methanol; Propanol","PeriodicalId":7348,"journal":{"name":"Advances in Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89538348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

The Analysis About Vertical Differentiation, Cost Structure and the Stability of Collusion 垂直差异化、成本结构与合谋稳定性分析

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/6199

Huishuang He

引用次数: 0

The Reason of Photons Angular Distribution at Electron-Positron Annihilation in a Positron-Emission Tomograph 正电子发射层析成像中正电子湮灭时光子角分布的原因

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/6062

A. Volobuev, E. Mokin

引用次数: 1

Study on Jilin Province’s Population Growth Trend Model 吉林省人口增长趋势模型研究

Advances in Natural Science Pub Date : 2014-12-26 DOI: 10.3968/J.ANS.1715787020120504.ZJ001

Jin Yuzi