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Annual Fluctuations and displacements of Inter Tropical Convergence Zone (ITCZ) within the Range of Atlantic Ocean-India

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Open Journal of Ecology 2017年第1期7卷 12-33页

作者： Hassan Lashkari Zainab Mohammadi Ghassem Keikhosravi Department of Synoptic Climatology Shahid Beheshti University Tehran Iran

Inter Tropical Convergence Zone (ITCZ) is one of the major systems in making the general circulation of atmosphere. Many climatologists believe that the starting point of the general circulation of atmosphere is from this system. It seems that the annual displacement of this system is coordinated with the sun. In this study we have tried to investigate the annual and seasonal displacement of this system within the range of Middle East, especially within the range of longitude of Iran in a long period of time (statistical period of 66 years). This is the first study in the field of ITCZ monthly and annual long-term changes in Iran. In this study, not only his exact position on Africa and South West Asia ITCZ is determined, it also shows the change in the period of 66 years. These results can also be used on regional climate changes. For this purpose topographic and surface level pressure maps are 1000 and 850 hpa and they were approximately extracted monthly for 12 months of the year from 1948 to 2013 and also they were extracted from the National Oceanic and Atmospheric Ad-ministration Site in America within the range of 30°west to 110°east, and they were extracted by using the flow map of location (ITCZ). Due to the sudden displacement in the ITCZ bar path in the two seasons of summer and winter, on the Middle East region, the direct impact of this displacement on sudden changes of seasons, the start and end of untimely rains, its impacts on agricultural products and water recourses of the country so all these reasons are essential that this phenomenon should be studied carefully. Studies have shown that ITCZ is not a coordinated solar system and its displacement is not coordinate with the apparent annual displacement of the sun. October is the only month of ITCZ that within the range of 10 northern degrees in all the ranges of longitude 20°west to 110°east has an approximate orbital shape. In 6 months of the year (from November to April) (ITCZ) wit

关键词： ITCZ Atlantic Ocean-India Annual Fluctuations displacements

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Double Beams to Measure Three-dimensional Rigid Body displacements

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Semiconductor Photonics and Technology 1997年第2期3卷 78-81页

作者： ZHOU Jian,CHEN Wenyi,ZHAO Hong TIAN Feng,TAN Yushan (Research Institute for Laser and Infrared Applications,Xi’an Jiaotong University,Xi’an 710049,CHN)

A new method for measuring 3-D rigid body displacements is proposed,in which two perpendicular beams are emitted onto two sensitive planes of PSDs being perpendicular to each *** method can be used to measure 1-D or 2-D displacements when ***,the experimental results are presented,which demonstrate that the new method has high accuracy,fast processing speed,high reliability,and easily being realized.

关键词： displacements Measurement Photodetector PSD

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Model test on sand retaining wall reinforced with denti-strip inclusions

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Science China(Technological Sciences) 2008年第12期51卷 2259-2269页

作者： ZHANG MengXi1 & ZHOU Huai1,2 1 Department of Civil Engineering,Shanghai University,Shanghai 200072,China 2 Shanghai Chengtou City Land(Group) Corporation,Shanghai 200438,China Department of Civil Engineering Shanghai University Shanghai Chengtou City Land (Group) Corporation

In conventional reinforced soil structures,the reinforcements are often laid hori-zontally in the *** this paper,a new concept of soil reinforced with denti-strip inclusions was proposed and a series of laboratory model tests were carried out on sand retaining wall reinforced with denti-strip *** the horizontal displacements of the facing,the lateral earth pressures acting on vertical elements were measured.A microscopic measurement was performed to investigate the deformation and progressive failure of the sand within model retaining *** on the image analytical technique,the bearing capability and interaction mechanism of reinforced sand retaining wall were *** model of the initial shear failure and potential failure surface were also put *** the experimental results,it is shown that denti-strip inclusions can increase the bearing capability of retaining wall significantly and restrict the facing displacements efficiently,as compared with conventional horizontal reinforcement.

关键词： denti-strip inclusions reinforced sand retaining wall model test horizontal facing displacements lateral earth pressure on denti-elements failure surface

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ON THE UPPER-LIMITS OF HOLOGRAPHIC, SPECKLE AND MOIRE INTERFEROMETRIES

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Science China Mathematics 1990年第3期33卷 308-316页

作者：方竞戴福隆 Peking University Beijing 100871 PRC Tsinghua University Beijing 100084 PRC

Based on the Fourier analysis and speckle statistics, and mainly focusing on the range of holographic interferometry, this paper presents the expressions of the maximum displacement measurable by holographic, speckle and moire interferometries. The relation among these three interferomtries is found from the spectrum analysis of the recording results, and the relation between the mean size of speckle and the displacement measurable by holographic interferometry is given through the mutual-correlation analysis. As two special situations of holographic interferometry, the upper-limits of the range of speckle and moire interferometries are presented.

关键词： spectrum analysis speckle statistics maximum measurable displacements

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Modeling of Geometric Variations Within Three-Dimensional Tolerance Zones

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Journal of Harbin Institute of Technology(New Series) 2018年第2期25卷 41-49页

作者： Heping Peng Wenlong Lu School of Electromechanical&Architectural Engineering Jianghan UniversityWuhan 430056China School of Mechanical Science&Engineering Huazhong University of Science and TechnologyWuhan 430074China

A tolerance modeling method of geometric variations within three-dimensional(3D) tolerance domain is *** to the classification method of feature variations and classes of invariance or symmetry in the new generation Geometrical Product Specifications(GPS) system,the proposed method is based on the Small Displacement Torsor(SDT) concept,and SDT is used to represent the geometric deviations between the nominal feature and the fitting feature. Furthermore,the variation zones of several kinds complex or irregular geometric features are constructed,and the corresponding tolerance modeling methods are discussed respectively. Finally,an example is presented to verify the efficiency of the presented method for modeling 3D dimensional and geometrical *** proposed modeling method based on the complete mathematical foundation conforms with the design philosophy and principle of the new generation GPS standards system.

关键词： geometrical product specifications(GPS) tolerance modeling feature geometric variations small displacements torsor(SDT)

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Mobility Pattern of Taxi Passengers at Intra-Urban Scale:Empirical Study of Three Cities

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Journal of Systems Science and Information 2017年第6期8卷 537-555页

作者： Mengqiao XU Ling ZHANG Wen LI Haoxiang XIA Faculty of Management and Economics Dalian University of TechnologyDalian 116024China

The study of human mobility patterns is of both theoretical and practical values in many aspects. For long-distance travel, a few research endeavors have shown that the displacements of human travels follow a power-law distribution. However, controversies remain regarding the issue of the scaling laws of human mobility in intra-urban areas. In this work, we focus on the mobility pattern of taxi passengers by examining five datasets of three metropolitans. Through statistical analysis, we find that the lognormal distribution with a power-law tail can best approximate both the displacement and the duration time of taxi trips in all the examined cities. The universality of the scaling laws of human mobility is subsequently discussed, in view of the analysis of the data. The consistency of the statistical properties of the selected datasets that cover different cities and study periods suggests that, the identified pattern of taxi-based intra-urban travels seems to be ubiquitous over cities and time periods.

关键词： human mobility pattern taxi travel displacements duration time

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Numerical Analysis of the Interaction between Shallow （Square, Circular and Strip） Foundations and Subsoil

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Journal of Civil Engineering and Architecture 2013年第7期7卷 875-886页

作者： L'ubos Hrustinec Department of Geotechnics Faculty of Civil Engineering Slovak University of Technology in Bratislava Bratislava 813 68Slovakia

In this paper, the effects of the stiffness of circular, square and strip foundation structures and bonding effects were analyzed. Presented analysis was oriented on the influence of stiffness system ＂foundation--subsoil＂ and bonds （bi-directional bond and one-directional bond with and without friction）. The results of numerical calculations have proved that the relative stiffness of system ＂foundation--subsoil＂ affect considerably the value and the distribution of contact stresses （vertical normal and shear stresses） in the foundation gap and value of the displacements （settlement, deflection and relative deformations） of foundation. From the numerical point of view, this problem was solved by deformation variant of the FEM （finite element method）. The numerically obtained results were presented in the graphical and tabular forms. Obtained results were qualitative and quantitative compared with one another. From the calculation results it is obvious that relative stiffness of the system ＂foundation structure--subsoil＂ substantially affects distribution of contact stresses in the foundation subsoil and displacements （settlement, deflection and relative deformations, flexibility） of foundation. In the case of flexible foundations, the bond on the contact surfaces must be considered during the calculation. On the other hand, the effects of friction on the contact surface between the foundation and subsoil affect the distribution of contact stresses and deformations only to smaller extent.

关键词： Shallow foundations contact stresses displacements stiffness of foundations FEM modeling.

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Serviceability Analysis of Non-Prismatic Timber Beams: Derivation and Validation of New and Effective Straightforward Formulas

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Open Journal of Civil Engineering 2017年第1期7卷 32-62页

作者： Giuseppe Balduzzi Georg Hochreiner Josef Füssl Ferdinando Auricchio Institute for Mechanics of Materials and Structures (IMWS) Vienna University of Technology Vienna Austria Department of Civil Engineering and Architecture (DICAr) University of Pavia Pavia Italy

This paper provides innovative and effective instruments for the simplified analysis of serviceability limit states for pitched, kinked, and tapered GLT beams. Specifically, formulas for the evaluation of maximal horizontal and vertical displacements are derived from a recently-proposed Timoshenko-like non-prismatic beam model. Thereafter, the paper compares the proposed serviceability analysis formulas with other ones available in literature and with highly-refined 2D FE simulations in order to demonstrate the effectiveness of the proposed instruments. The proposed formulas lead to estimations that lie mainly on the conservative side and the errors are smaller than 10% (exceptionally up to 15%) in almost all of the cases of interest for practitioners. Conversely, the accuracy of the proposed formulas decreases for thick and highly-tapered beams since the beam model behind the proposed formulas cannot tackle local effects (like stress concentrations occurring at bearing and beam apex) that significantly influence the beam behavior for such geometries. Finally, the proposed formulas are more accurate than the ones available in literature since the latter ones often provide non-conservative estimations and errors greater than 20% (up to 120%).

关键词： Serviceability Analysis Non-Prismatic Timber Beams Tapered Beams Pitched Beams Maximal displacements

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Infilled Reinforced Concrete Beams for Sustainable Construction

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Journal of Civil Engineering and Architecture 2013年第11期7卷 1369-1374页

作者： Patel Rakesh Dubey Sheo Kumar Pathak Krishna Kant Department of Civil Engineering Maulana Azad National Institute of Technology Bhopa1462051 India Department of Civil and Environmental Engineering National Institute of Technical Teachers' Training and Research Bhopal462002 India

This paper presents a study carried out on infilled reinforced concrete beams for sustainable construction. In reinforced concrete beams, less stressed concrete below neutral axis can be replaced by some light weight material to reduce the weight of the structure and also achieve the economy. The used infilled material is brick. Sustainability can be achieved by replacing the partially used concrete. By saving concrete, the authors save cement, which reduces the green house gases emissions. So it is considered as environment friendly. Since infilled beam acts like a layered member, there needs a theory to analyze it. Method of initial functions is used for the analysis of the infilled RC （reinforced concrete） beams. This method is successfully applied on infilled beam. Results show that physical conditions are verified for infilled beam.

关键词： Initial functions infilled beams brick masonry displacements stresses

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A displacement-based back-analysis method for rock mass modulusand horizontal in situ stress in tunneling-Illustrated with a case study

A displacement-based back-analysis method for rock mass modu...

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中国科学院地质与地球物理研究所2006学术年会

作者： L.Q.Zhang~a,Z.Q.Yue~b,Z.F.Yang~a,J.X.Qi~b,F.C.Liu~b (a Institute of Geology and Geophysics,Chinese Academy of Sciences,P.O.Box 9825, Beijing 100029,PR China) (b Department of Civil Engineering,The University of Hong Kong,Pokfulam Road,Hong Kong,PR China) (c Beijing Hydroelectric Investigation and Design Institute,Beijing,PR China)

This paper presents a displacement based back-analysis method for the determination of rock mass modulus(E) and the horizontal in situ stress(P) perpendicular to the axis line of the tunnel excavation in hard and intact rock *** rock mass is assumed to respond in an isotropic and linear elastic ***,the method is a best-fit solution of back-analysis by comparing the measured displacements near a tunnel face during excavation with those calculated using a three-dimensional finite element *** method can be applied efficiently and effectively by iterative algorithms such as direct search technique and damping least square *** particular,a three-dimensional finite element pattern technique(3-D FEPT) is used to compute the theoretical displacements for saving computation *** method is further illustrated with a case *** case study deals with a test adit at Zhanghewan Pumped Storage Power Station in Hebei Province,North *** is shown that the back-analyzed results of E and P are reliable and representative for the actual rock masses.

关键词： Back-analysis displacements Modulus In situ stresses 3-D FEPT Field tests

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