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Performance assessment of genetic programming(GP)and minimax probability machine regression(MPMR)for prediction of seismic ultrasonic attenuation

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Earthquake Science 2013年第2期26卷 147-150页

作者： Manoj Kumar Manav Mittal Pijush Samui National Institute of Rock Mechanics Kolar Gold Fields 563117 Karnataka India School of Mechanical and Building Science VIT University Centre for Disaster Mitigation and Management VIT University

The determination of seismic attenuation （s）（dB/cm） is a challenging task in earthquake science. This article employs genetic programming （GP） and minimax probability machine regression （MPMR） for prediction of s. GP is developed based on genetic algo- rithm. MPMR maximizes the minimum probability of future predictions being within some bound of the true regression function. Porosity （n）（%）, permeability （k）（millidarcy）, grain size （d）（μm）, and clay content （c）（%） have been considered as inputs of GP and MPMR. The output of GP and MPMR is s. The developed GP gives an equation for prediction of s. The results of GP and MPMR have been compared with the artificial neural net- work. This article gives robust models based on GP and MPMR for prediction of s.

关键词： Seismic attenuation Geneticprogramming Minimax probability machineregression Artificial neural network Prediction

Mining seismicity in the Witwatersrand Basin:monitoring,mechanisms and mitigation strategies in perspective

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Journal of Rock Mechanics and Geotechnical Engineering 2012年第3期4卷 228-249页

作者： K. L. Riemer R. J. Durrheim gold fields Gauteng South Africa University of the Witwatersrand & CSIR Centre for Mining Innovation Gauteng South Africa

The Kaapvaal Craton in South Africa hosts one of the largest gold placer deposits in the world. Mining in the Witwatersrand Basin here has been the source of about one third to one half of the gold ever produced in the world. gold was discovered in the Johannesburg area in 1886 and after 120 years of continuous operation, mining is currently approaching depths of 4 000 m. In spite of the challenges and risks that the industry has had to deal with including rock temperature, ventilation and water, one of the most feared hazards in the basin has been the threat from the ongoing occurrence of seismicity and rockbursts. The problem first manifested itself by way of the occurrence of tremors roughly twenty years after the commencement of mining operations. This paper traces the history of the approach to rockbursts and seismicity during the 120 year history of mining in the basin. It portrays a picture of the mining seismicity in terms of monitoring phases, mechanisms and mitigation strategies. The work of research organizations over the years is highlighted with a brief mention of current regulation strategies on the part of the mining inspectorate.

关键词： Witwatersrand Basin monitoring mechanisms mitigation prevention protection prediction

Meaningful comparison of photocatalytic properties of {001} and {101} faceted anatase TiO2 nanocrystals

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Science Bulletin 2016年第13期61卷 1003-1012页

作者： Yang Lu Yipeng Zang Haimin Zhang Yunxia Zhang Guozhong Wang Huijun Zhao Key Laboratory of Materials Physics Centre for Environmentaland Energy Nanomaterials Anhui Key Laboratory of Nanomaterials and Nanotechnology Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China University of Science and Technology of China Hefei 230026China Centre for Clean Environment and Energy Griffith UniversityGold Coast Campus Gold Coast QLD 4222 Australia

The facet-dependent photocatalytic performance of TiO_2 nanocrystals has been extensively investigated due to their promising applications in renewable energy and environmental fields. However, the intrinsic distinction in the photocatalytic oxidation activities between the {001}and {101} facets of anatase TiO_2 nanocrystals is still unclear and under debate. In this work, a simple photoelectrochemical method was employed to meaningfully quantify the intrinsic photocatalytic activities of {001} and{101} faceted TiO_2 nanocrystal photoanodes. The effective surface areas of photoanodes with different facets were measured based on the monolayer adsorption of phthalic acid on TiO_2 photoanode surface by an ex situ photoelectrochemical method, which were used to normalize the photocurrents obtained from different faceted photoanodes for meaningful comparison of their photocatalytic activities. The results demonstrated that the {001} facets of anatase TiO_2 nanocrystals exhibited much better photocatalytic activity than that of {101} facets of anatase TiO_2 nanocrystals toward photocatalytic oxidation of water and organic compounds with different functional groups(e.g.,–OH, –CHO, –COOH). Furthermore, the instantaneous kinetic constants of photocatalytic oxidation of pre-adsorbates on {001} faceted anatase TiO_2 photoanode are obviously greater than those obtained at {101} faceted anatase TiO_2 photoanode, further verifying the higher photocatalytic activity of {001} facets of anatase TiO_*** work provided a facile photoelectrochemical method to quantitatively determine the photocatalytic oxidation activity of specific exposed crystal facets of a photocatalyst, which would be helpful to uncover and meaningfully compare the intrinsic photocatalytic activities of different exposed crystal facets of a photocatalyst.

关键词： Anatase TiO2 Crystal facet Photocatalysis Structure-activity relationships

CALCULATION OF POWER LINE fields BETWEEN CIRCULAR CONDUCTORS

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第1期4卷 51-68页

作者： ANDREW SEAGAR SALAKCHIT NILBOWORN School of Engineering Griffith University Gold CoastQLD 4222Australia Department of Electrical Engineering Rajamangala University of Technology Srivijaya 1 Ratchadamnoennok Rd MuangSongkhla 90000Thailand

It is important to calculate the electric field at the surface of high voltage direct current power transmission lines,since it is this field which governs the onset of corona discharge and the power loss arising therefrom.A method is presented here to calculate the electric field based on an implementation of the boundary element method for conductors of strictly circular cross *** the circular geometry it is possible to resolve all integrals involved analytically.A Galerkin approach is adopted,giving the solution in the spatial frequency *** allows a controlled truncation of the system matrix by choice of which frequency components to *** transpires that the low frequency components are the most important *** test cases are used to quantify the accuracy of the solution with respect to truncation and distance from the *** is found that the accuracy increases with distance from the surface,but for all distances can be controlled by choosing an appropriate level of truncation.

关键词： Boundary element method transmission lines electric field Laplace’s equation.

医院内直接观察下治疗结核病时治疗卡对坚持规律治疗的作用

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国际结核病与肺部疾病杂志 1998年第1期 8-11页

作者： P.Sonnenberg M.H.Ross S.C.P.M.Shearer J.Murray 何广学 Department of Community Health University of the Witwatersrand gold fields of South Africa Johannesburg National Centre for Occupational Health Department of HealthJohamesburgSouth Africa

我们评价在结核病病房由病人和卫生工作者共同签字的治疗卡对坚持规律治疗的影响。通过检测每个病人的尿标本来估价坚持规律治疗情况,在干预之前和干预后2周、6周和16个月检测尿标本中异烟肼和利福平。干预前的坚持规律治疗率为62％,在... 详细信息

我们评价在结核病病房由病人和卫生工作者共同签字的治疗卡对坚持规律治疗的影响。通过检测每个病人的尿标本来估价坚持规律治疗情况,在干预之前和干预后2周、6周和16个月检测尿标本中异烟肼和利福平。干预前的坚持规律治疗率为62％,在短期、中期和长期干预后的坚持规律治疗率分别是88％、91％和93％(P=0.03,P=0.02,P<0.01)。医院内能够成功的实施直接观察下治疗的说法并不总是正确的。简单廉价的方法能够改善坚持规律治疗并对结核病控制产生影响。

关键词：结核病坚持规律治疗医院直接观察下治疗

The Tight Sandstone Reservoir in Pyramid Structure,Upper Paleozoic of Erdos Basin

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Acta Geologica Sinica(English Edition) 2015年第A01期89卷 104-105页

作者： WEI Xinshan LUO Shunshe SUN Liuyi REN Junfeng ZHAO Huitao LIU Xiaopeng National Engineering Laboratory for Exploration & Development of Low Permeability Oil/Gas fields Xi'anShaanxi 710018 China PetroChina Changqing Oilfield Company Xi 'an Shaanxi 710018 China Yangtze University Jingzhou Hubei 434023 China

Pyramid＇s Arabic meaning ＂cone＂, it is a square bottom spire of stone building in Pyramid, the ancient Egyptian burial tomb of the king and queen are the most typical. Because of its grand scale, its sides are composed of plurality of triangular or triangular surfaces which are connected to the top, the area is very small, even a spire shaped, resembling Chinese characters in ＂gold＂ word, so the image is translated as ＂Pyramid＂.

关键词： SANDSTONE PYRAMIDS BASINS (Geology) RESERVOIRS PALEOZOIC Era CHINA

Coupling model for waves propagating over a porous seabed

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Theoretical & Applied Mechanics Letters 2015年第2期5卷 85-88页

作者： C.C.Liao Z.Lin Y.Guo D.-S.Jeng Department of Civil Engineering Shanghai Jiao Tong University School of Engineering University of Aberdeen School of Engineering University of Bradford Griffith School of Engineering Griffith University Gold Coast Campus

The wave-seabed interaction issue is of great importance for the design of foundation around marine infrastructures. Most previous investigations for such a problem have been limited to uncoupled or one- way coupled methods connecting two separated wave and seabed sub models with the continuity of pressures at the seabed surface. In this study, a strongly coupled model was proposed to realize both wave and seabed processes in a same program and to calculate the wave fields and seabed response simultaneously. The information between wave fields and seabed fields were strongly shared and thus results in a more profound investigation of the mechanism of the wave-seabed interaction. In this letter, the wave and seabed models were validated with previous experimental tests. Then, a set of application of present model were discussed in prediction of the wave-induced seabed response. Numerical results show the wave-induced liquefaction area of coupled model is smaller than that of uncoupled model.

关键词： Coupled model Momentum source Internal wave-maker Seabed response Pore pressure Liquefaction

{001} facets dominated anatase TiO_(2) : Morphology, formation/etching mechanisms and performance

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Science China Chemistry 2013年第4期56卷 402-417页

作者： ZHANG HaiMin LIU XiaoLu LI YiBing LI Ying ZHAO HuiJun Centre for Clean Environment and Energy and Griffith School of EnvironmentGriffith UniversityGold Coast CampusQLD 4222Australia Key Laboratory of Materials Physics Hefei Key Laboratory of Nanomaterials and NanotechnologyInstitutes of Solid State PhysicsChinese Academy of SciencesHefei 230031China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China

Controllable growth of anatase TiO_(2)crystals with exposed high reactive crystal facets has aroused great attention in the fields of science and technology due to their unique structure-dependent ***,much effort has been paid to synthesize anatase TiO_(2)crystals with exposed high reactive{001}***,we review the recent progress in synthesizing{001}facets dominated anatase TiO_(2)crystals with different morphologies by various synthetic ***,our review is mainly focused on the formation/etching mechanisms of{001}facets dominated anatase TiO_(2)crystals based on our and other *** extensive application potentials of the anatase TiO_(2)crystals with exposed{001}facets have been summarized in this review such as photocatalysis,photoelectrocatalysis,solar energy conversion,lithium ion battery,and hydrogen generation Based on the current studies,we give some perspectives on the research *** believe that this comprehensive review on anatase TiO_(2)crystals with high reactive{001}facets can further promote the relative research in this field.

关键词： anatase TiO_(2) high reactive{001}facets crystal growth formation/etching mechanisms hydrothermal synthesis

THE PLASMA CONDITION FOR THE KINEMATICAL FORCE-FREE MAGNETIC FIELD

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Chinese Science Bulletin 1985年第5期30卷 588-592页

作者：李中元胡文瑞 University of Science and Technoloy of China Hefei Institute of Mechanics Academia Sinica Beijinghe force-free field describes the configuration of magnetic field in the solar chromosphere and coronal active region in the Earth's magnetosphere and even in the comet plasma. The force-free field has extensive applications in the solar physical or space physical environment. Generally the theoretical models of the force-free fields are constructed first and then compared with the observations. In the 50's Gold

The force-free field describes the configuration of magnetic field in the solar chromosphere and coronal active region, in the Earth’s magnetosphere, and even in the comet plasma. The force-free field has extensive applications in the solar physical or space physical environment. Generally, the theoretical models of the force-free fields are constructed first, and then, compared with the observations. In the 50’s,

关键词： comet rotation frozen Thema discus satisfy esses adient resultant momentum