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Study of the Efficiency of Vertical Drains by an FEM Method in Soil Treatment for Road Projects: Case of the Development and Bitumination Works of the ROCADE Porto-Novo in Benin
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作者 Cheikh Diallo Diène Vitouley Kossi Ghyslain Joël +1 位作者 Mamadou Tine Apanda Mbongote Johnny 《Open Journal of Civil Engineering》 2024年第3期435-455,共21页
This article aims to study the efficiency of coupled vertical drains for the treatment of long-lasting compressible clay soils for the road project platform of the ring road of Porto Novo, capital of Benin. The experi... This article aims to study the efficiency of coupled vertical drains for the treatment of long-lasting compressible clay soils for the road project platform of the ring road of Porto Novo, capital of Benin. The experimental data allowed us to estimate a consolidation of 29% in 9 months, justifying the drainage of the soil. In order to study the efficiency of drainage, a FEM model was proposed simulating different scenarios. These include a drainless road, pavements equipped with vertical drains with meshes of 0.5 m 0.5 m, 1 m 1 m and 1.5 m 1.5 m respectively and horizontal drains. The results expressed in terms of variations in vertical stresses, effective stresses and shear deformations revealed significant variations in pavement performance depending on the mesh size of the vertical drains. The configuration with a mesh of 0.5 m 0.5 m showed the least deformations, thus indicating a reduction in deformations and better stress distribution. However, the other mesh configurations showed variable results, underlining the importance of choosing the right mesh for the specific project conditions. 展开更多
关键词 PAVEMENT vertical Drains horizontal Drains Modelling Plaxis2D ROCADE de Porto-Novo
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An Integrated Scheduling Algorithm for the Same Equipment Process Sequencing Based on the Root-Subtree Vertical and Horizontal Pre-Scheduling
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作者 Zhiqiang Xie Haikun Teng +1 位作者 Anak Agung Ayu Putri Ardyanti Xu Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期179-200,共22页
Given the existing integrated scheduling algorithms,all processes are ordered and scheduled overall,and these algorithms ignore the influence of the vertical and horizontal characteristics of the product process tree ... Given the existing integrated scheduling algorithms,all processes are ordered and scheduled overall,and these algorithms ignore the influence of the vertical and horizontal characteristics of the product process tree on the product scheduling effect.This paper presents an integrated scheduling algorithm for the same equipment process sequencing based on the Root-Subtree horizontal and vertical pre-scheduling to solve the above problem.Firstly,the tree decomposition method is used to extract the root node to split the process tree into several Root-Subtrees,and the Root-Subtree priority is set from large to small through the optimal completion time of vertical and horizontal pre-scheduling.All Root-Subtree processes on the same equipment are sorted into the stack according to the equipment process pre-start time,and the stack-top processes are combined with the schedulable process set to schedule and dispatch the stack.The start processing time of each process is determined according to the dynamic start processing time strategy of the equipment process,to complete the fusion operation of the Root-Subtree processes under the constraints of the vertical process tree and the horizontal equipment.Then,the root node is retrieved to form a substantial scheduling scheme,which realizes scheduling optimization by mining the vertical and horizontal characteristics of the process tree.Verification by examples shows that,compared with the traditional integrated scheduling algorithms that sort the scheduling processes as an overall,the integrated scheduling algorithmin this paper is better.The proposed algorithmenhances the process scheduling compactness,reduces the length of the idle time of the processing equipment,and optimizes the production scheduling target,which is of universal significance to solve the integrated scheduling problem. 展开更多
关键词 horizontal and vertical pre-scheduling the priority of the Root-Subtree the equipment process pre-start time the dynamic start time strategy of the equipment process
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Three-dimensional crustal movement and the activities of earthquakes,volcanoes and faults in Hainan Island,China 被引量:9
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作者 Yaxuan Hu Ming Hao +1 位作者 Lingyun Ji Shangwu Song 《Geodesy and Geodynamics》 2016年第4期284-294,共11页
Hainan Island is a seismic active region, where Qiongshan M7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast p... Hainan Island is a seismic active region, where Qiongshan M7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast part of the island. Here is also a magmatic active region. The lava from about 100 volcanoes covered more than 4000 km^2. The latest eruptions occurred on Ma'anling-Lei Huling volcanoes within 10,000 years. The neotectonic movement has been determined by geological method in the island and its adjacent areas. In the paper, the present-day 3D crustal movement is obtained by using Global Positioning System (GPS) data observed from 2009 to 2014 and leveling observations measured in 1970s and 1990s respectively. The results show the horizontal movement is mainly along SEE direction relative to the Eurasian Plate. The velocities are between 4.01 and 6.70 mm/a. The tension rate near the NSB is less than I mm/a. The vertical movement shows the island uplifts as a whole with respect to the reference benchmark Xiuyinggang. The average uplifting rate is 2.4 mm/a. The rates are 2-3 mm/a in the northwest and 3-5mm/a in the northwest. It shows the deformation pattern of the southwest island is upward relative to the northeast, which is different from the result inferred from the coastal change and GPS. Haikou and its adjacent region present a subsidence in a long time. The southern part of the middle segment of the Wangwu-Wenjiao fault uplifts relative to the northern. Meanwhile, the western part uplifts relative to the eastern NSB. The vertical crustal motion and the two normal faults nearly correspond to the terrain. The NSB is located along the Puqiangang-Dazhibo fault, which is assessed as a segmented fault with a dip of 80°-90° and party exposed. The 3D deformations and other studies reveal the present activities of earthquakes, volcanoes and the faults. The small earthquakes will still occur in the NS belt and the volcanoes are not active now. 展开更多
关键词 Hainan Island horizontal movement vertical movement EARTHQUAKE VOLCANO FAULT Seismic belt
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Sensitivity of WRF simulated typhoon track and intensity over the South China Sea to horizontal and vertical resolutions 被引量:5
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作者 Zhiyuan Wu Changbo Jiang +2 位作者 Bin Deng Jie Chen Xiaojian Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第7期74-83,共10页
To determine the grid resolutions of the WRF model in the typhoon simulation,some sensitivity analysis of horizontal and vertical resolutions in different conditions has been carried out.Different horizontal resolutio... To determine the grid resolutions of the WRF model in the typhoon simulation,some sensitivity analysis of horizontal and vertical resolutions in different conditions has been carried out.Different horizontal resolutions(5,10,20,30 km),nesting grids(15 and 5 km),different vertical resolutions(35-layers,28-layers,20-layers)and different top maximum pressures(1 000,2 000,3 500,5 000 Pa)had been used in the mesoscale numerical model WRF to simulate the Typhoon Kai-tak.The simulation results of typhoon track,wind speed and sea level pressure at different horizontal and vertical resolutions have been compared and analyzed.The horizontal and vertical resolutions of the model have limited effect on the simulation effect of the typhoon track.Different horizontal and vertical resolutions have obvious effects on typhoon strength(defined by wind speed)and intensity(defined by sea level pressure,SLP),especially for sea level pressure.The typhoon intensity simulated by the high-resolution model is closer to the real situation and the nesting grids can improve computational accuracy and efficiency.The simulation results affected by vertical resolution using 35-layers is better than the simulation results using 20-layers and 28-layers simulations.Through comparison and analysis,the horizontal and vertical resolutions of WRF model are finally determined as follows:the two-way nesting grid of 15 and 5 km is comprehensively determined,and the vertical layers is 35-layers,the top maximum pressure is 2 000 Pa. 展开更多
关键词 sensitivity analysis TYPHOON track and INTENSITY horizontal and vertical RESOLUTIONS TYPHOON Kai-tak WRF
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Urban Three-dimensional Expansion and Its Driving Forces——A Case Study of Shanghai,China 被引量:20
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作者 SHI Longyu SHAO Guofan +4 位作者 CUI Shenghui LI Xuanqi LIN Tao YIN Kai ZHAO Jingzhu 《Chinese Geographical Science》 SCIE CSCD 2009年第4期291-298,共8页
Urban expansion is a phenomenon of urban space increase,and an important measuring index of the process of urbanization.Taking Shanghai as an example,the changes of urban average height and built-up area were studied ... Urban expansion is a phenomenon of urban space increase,and an important measuring index of the process of urbanization.Taking Shanghai as an example,the changes of urban average height and built-up area were studied to represent city's vertical and horizontal increases respectively,and statistical methods were used to analyze the driving forces of urban expansion.The research drew following conclusions:1) The urban expansion process of Shanghai from 1985 to 2006 had a clear periodic feature,and could be divided into three stages:vertical expansion in dominance,coordinated vertical and horizontal expansion,and horizontal expansion in dominance.2) The average height and quantity of buildings in core city were significantly bigger than those in suburbs,but the changing speed of the latter was faster.And 3) urbanization process was the major driving force for the city's horizontal expansion,while industrial structure improvement was the key driving factor for the vertical expansion.Those two driving forces were simultaneously affected by city's political factors. 展开更多
关键词 urban expansion three-dimensional space URBANIZATION urban vertical expansion urban horizontal ex-pansion SHANGHAI China
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Experimental Study on Bubble Pulse Features Under the Combined Action of Horizontal and Vertical Walls 被引量:5
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作者 王诗平 初文华 张阿漫 《China Ocean Engineering》 SCIE EI CSCD 2014年第3期293-301,共9页
The pulse features of a bubble have a close connection with the boundary condition. When a bubble moves near a rigid wall, it will be attracted by the Bjerknes force of the wall, and a jet pointing at the wall will be... The pulse features of a bubble have a close connection with the boundary condition. When a bubble moves near a rigid wall, it will be attracted by the Bjerknes force of the wall, and a jet pointing at the wall will be generated. In real application, the bubble may move under the combined action of walls in different directions when it forms at the corner of a pipe or at the bottom of a dam. The motion of the bubble shows complex and nonlinear characteristics under these conditions. In order to investigate the bubble pulse features near complex walls, a horizontal wall and a vertical wall are put into the experimental water tank synchronously, and an electric circuit with 200 voltages is designed to generate discharge bubbles, and then experimental study on the bubble pulse features under the combined action of horizontal and vertical walls is carried out. The influences of the combined action of two walls on the bubble shape, pulse period, moving trace and inside jet are obtained by changing the distances from bubble center to the two walls. It aims at providing references for the relevant theoretical and numerical research. 展开更多
关键词 BUBBLE combined action horizontal and vertical walls experimental study
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Research and application on three-dimensional seismic and vibration isolation for building 被引量:5
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作者 魏陆顺 周福霖 +1 位作者 谭平 任珉 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第1期62-66,共5页
This paper presents the study of a three-dimensional(3D) isolation system.Firstly,the authors investigated the effects of an innovative 3D isolator,which was composed of a connecting plate,a rubber pad for vibration i... This paper presents the study of a three-dimensional(3D) isolation system.Firstly,the authors investigated the effects of an innovative 3D isolator,which was composed of a connecting plate,a rubber pad for vibration isolation in the vertical direction and a horizontal rubber bearing for seismic isolation in both horizontal directions.Secondly,the authors designed such a vibration isolation system and installed it underneath two specific residential buildings which were built directly over an existing subway communication hub platform in Beijing.These buildings required good performance vibration and seismic isolation system to reduce the impact from the running of nearby subway trains.Finally,in situ tests were conducted for both the isolated and the non-isolated buildings for the purpose of comparison.The test results showed that the maximum acceleration response level of the isolated superstructure is reduced by 10% as compared to that of the platform.The maximum attenuation of vibration reaches up to 25 dB.The 3D system explored in this paper is very effective in control and suppression of building vibration induced by earthquakes or running of trains. 展开更多
关键词 three-dimensional seismic and vibration isolator vertical vibration isolation horizontal seismic isolation engineering application
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Accelerating BP-Based Iterative Low-Density Parity-Check Decoding by Modified Vertical and Horizontal Processes 被引量:2
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作者 陈婧文 仰枫帆 +1 位作者 罗琳 THO Le-Ngoc 《Journal of Southwest Jiaotong University(English Edition)》 2009年第4期275-282,共8页
Two modified BP algorithms related to vertical and horizontal processes are proposed to accelerate iterative low-density parity- check (LDPC) decoding over an additive white Gaussian noise (AWGN) channel, where th... Two modified BP algorithms related to vertical and horizontal processes are proposed to accelerate iterative low-density parity- check (LDPC) decoding over an additive white Gaussian noise (AWGN) channel, where the newly updated extrinsic information is immediately used in the current decoding round. Theoretical analysis and simulation results demonstrate that both the modified approaches provide significant performance improvements over the traditional BP algorithm with almost no additional decoding complexity. The proposed algorithm with modified horizontal process offers even better performance than another algorithm with the modified horizontal process. The two modified BP algorithms are very promising in practical communications since both can achieve an excellent trade-off between the performance and decoding complexity. 展开更多
关键词 LDPC codes Iterative decoding BP algorithm Extrinsic information horizontal process vertical process
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A NOVEL METHOD FOR CALCULATING VERTICAL VELOCITY:A RELATIONSHIP BETWEEN HORIZONTAL VORTICITY AND VERTICAL MOVEMENT 被引量:7
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作者 丁治英 赵向军 +1 位作者 高松 罗亚丽 《Journal of Tropical Meteorology》 SCIE 2016年第2期208-219,共12页
The present work provides a novel method for calculating vertical velocity based on continuity equations in a pressure coordinate system.The method overcomes the disadvantage of accumulation of calculating errors of h... The present work provides a novel method for calculating vertical velocity based on continuity equations in a pressure coordinate system.The method overcomes the disadvantage of accumulation of calculating errors of horizontal divergence in current kinematics methods during the integration for calculating vertical velocity,and consequently avoids its subsequent correction.In addition,through modifications of the continuity equations,it shows that the vorticity of the vertical shear vector(VVSV) is proportional to-ω,the vertical velocity in p coordinates.Furthermore,if the change of ω in the horizontal direction is neglected,the vorticity of the horizontal vorticity vector is proportional to-ω.When ω is under a fluctuating state in the vertical direction,the updraft occurs when the vector of horizontal vorticity rotates counterclockwise;the downdraft occurs when rotating clockwise.The validation result indicates that the present method is generally better than the vertical velocity calculated by the ω equation using the wet Q-vector divergence as a forcing term,and the vertical velocity calculated by utilizing the kinematics method is followed by the O'Brien method for correction.The plus-minus sign of the vertical velocity obtained with this method is not correlated with the intensity of d BZ,but the absolute error increases when d BZ is >=40.This method demonstrates that it is a good reflection of the direction of the vertical velocity. 展开更多
关键词 horizontal vorticity vertical velocity continuity equation Q-vector vorticity of vertical shear vector
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Present three-dimensional crustal deformation in Hainan Island 被引量:3
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作者 Hu Yaxuan Hu Jiuchang Hao Ming 《Geodesy and Geodynamics》 2014年第2期32-37,共6页
Hainan Island,located at the southeast edge of the Eurasian Plate,is affected by the motion of multiple plates,with its northeast edge mainly dilatating and its western margin presently compressing. By analyzing the G... Hainan Island,located at the southeast edge of the Eurasian Plate,is affected by the motion of multiple plates,with its northeast edge mainly dilatating and its western margin presently compressing. By analyzing the GPS rates during 1999- 2007 in Hainan and its adjacent region,we determined horizontal movement rates of 3. 0-21. 1 mm /a at the west of 104°E,evidently affected by the Indian Plate extrusion.Their directions are SE-SN-SW from east to west and are separated by the main fault. The principal strains have the same characteristics. The stations east of 104°E move mainly in the SEE direction. The eastward rates are 2. 1-8. 5 mm /a and northward rates are 0. 4- 2. 7 mm /a. The GPS rates during 2009- 2013 show that stations at the edge of the island move SEE relative to the Eurasian Plate,with rates relative to the mean benchmark,indicating that there are small relative movements between stations,whereas QION station,located in the middle,moves in the NW direction at a greater rate. Vertical differential movement is apparent in the northeast zone of the island. Upwelling of mantle plume material possibly influences the local stress.Three-dimensional GPS rates indicate that,at present,inherited crustal movement is dominant in Hainan. 展开更多
关键词 horizontal movement vertical movement principal strain crustal movement background Hainan aera
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Vertical and horizontal displacements of a reservoir slope due to slope aging effect,rainfall,and reservoir water 被引量:1
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作者 Dongzhen Jia Ye Zhou +3 位作者 Xiufeng He Nan Xu Zhixiang Yang Minfeng Song 《Geodesy and Geodynamics》 CSCD 2021年第4期266-278,共13页
Landslides are common hazards in reservoir areas and significantly affect dam operation and human lives.For the prevention and management of landslides,accurate assessment of the factors influencing their generation i... Landslides are common hazards in reservoir areas and significantly affect dam operation and human lives.For the prevention and management of landslides,accurate assessment of the factors influencing their generation is essential.This study evaluated the key external factors influencing horizontal and vertical displacements of Luobogang Reservoir Slope in Hanyuan County,China.Displacements had been monitored by a surface-displacement-monitoring system consisting of 118 GPS stations during 2012-2015.To identify the external driving factors,their influence zones,and slope responses,we analyzed 32 months of displacement measurements and other multi-source datasets using the empirical orthogonal function.Overall,the results show that slope aging effect,rainfall,and reservoir water levels are three main driving factors.For horizontal displacement,aging effect is the most critical factor and predominantly affects the edges of landslides,the gob cave,and the public building zones.The secondary factor is the reservoir water level,which mainly acts on the boundary between the slope and reservoir water surface.The closer the slope zone is to the reservoir water,the more significant the impact is.Regarding vertical displacement,the most important factor is rainfall.The vertical displacement caused by rainfall accounts for 56.76% of the total vertical displacements.However,rainfall induces elastic displacements that generally cause less damage to the slope.The secondary factor is aging effect,and the vertical displacement caused by aging effect accounts for 9.42%.However,seven individual zones are highly affected by slope aging effect,which is consistent with the distribution of public buildings. 展开更多
关键词 Reservoir slope horizontal and vertical displacements Influencing factors Aging effect Reservoir water level
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Separation performance of horizontal and vertical polyethersulfone hollow fiber UF modules 被引量:1
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作者 Alsalhy Qusay Fadhel 许振良 杨晓天 《Journal of Shanghai University(English Edition)》 CAS 2006年第2期173-178,共6页
The effect of hollow fiber module positions ( horizontal and vertical) on separation performance for PVA solution by using polyethersulfone (PES) hollow fiber ultrafiltration (UF) membrane with the molecular wei... The effect of hollow fiber module positions ( horizontal and vertical) on separation performance for PVA solution by using polyethersulfone (PES) hollow fiber ultrafiltration (UF) membrane with the molecular weight cut-off (MWCO) 30 000 has been discussed. Experimental results illustrated that the suitable operation conditions for PVA solution were as follows: trans-membrane pressure 2.1 bar, solution temperature 75℃ and feed velocity 0.32 m/s. Under these suitable operation conditions, the permeate flux is from 36.8 L/(m^2 ·h·bar) to 42.9 L/(m^2 ·h·bar) for the horizontal module and from 39.8 L/(m^2 ·h·bar) to 66.6 L/(m^2 ·h·bar) for the vertical module. Besides, the Separation performance of PES hollow fiber UF membrane was better by using vertical hollow fiber module than by using horizontal hollow fiber module. When the trans-membrane pressure increased from 1 bar to 2.1 bar, solution temperature from 50 ℃ to 75 ℃, feed solution velocity from 0.16 m/s to 0.32 m/s, the PVA rejection would increase from 95.8% to 99.7%, 95.4 96 to 98.6 %, 95.8 96 to 99.2 96 for horizontal module respectively, and from 98.8 96 to 99.8 %, 98.6 96 to 99.4 96, 98.5 96 to 99.4 96 for vertical module respectively. Therefore, PVA rejection in PES hollow fiber UF process was more than 98.5 96 for vertical module, and it is suitable for PVA recovery from wastewater. 展开更多
关键词 hollow fiber UF membrane POLYETHERSULFONE polyvinyl alcohol horizontal module vertical module.
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The Dynamic Behavior of a Discrete Vertical and Horizontal Transmitted Disease Model under Constant Vaccination 被引量:7
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作者 Mingshan Li Xiumin Liu Xiaoliang Zhou 《International Journal of Modern Nonlinear Theory and Application》 2016年第4期171-184,共15页
In this paper, a class of discrete vertical and horizontal transmitted disease model under constant vaccination is researched. Under the hypothesis of population being constant size, the model is transformed into a pl... In this paper, a class of discrete vertical and horizontal transmitted disease model under constant vaccination is researched. Under the hypothesis of population being constant size, the model is transformed into a planar map and its equilibrium points and the corresponding eigenvalues are solved out. By discussing the influence of coefficient parameters on the eigenvalues, the hyperbolicity of equilibrium points is determined. By getting the equations of flows on center manifold, the direction and stability of the transcritical bifurcation and flip bifurcation are discussed. 展开更多
关键词 vertical and horizontal Transmission VACCINATION Center Manifold Transcritical Bifurcation Flip Bifurcation
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Three-dimensional crustal deformation before and after the Wenchuan earthquake in Guanzhong and adjacent regions 被引量:1
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作者 Hu Yaxuan Qin Shanlan Hao Ming 《Geodesy and Geodynamics》 2015年第1期16-24,共9页
The recent plethora of GPS observations compensates for the 20-year-old lack in vertical displacement data for the Guanzhong region. The 2001—2007 three-dimensional(3D) crustal deformation data suggest regional mov... The recent plethora of GPS observations compensates for the 20-year-old lack in vertical displacement data for the Guanzhong region. The 2001—2007 three-dimensional(3D) crustal deformation data suggest regional movement with a horizontal velocity of 3—7 mm/a,predominantly from SSE in the west to SE in the east, and vertical inherited movement with velocity of -7 mm/a to 4 mm/a. After the Wenchuan earthquake, the GPS data suggest that the effect of the earthquake on the regional deformation is greater in the west than the east.The horizontal displacement increased during 2007—2008; however, the reverse was observed in 2008—2009. The vertical displacement in the western part of the region increased in 2008 and has been gradually returning to normal since 2009; however, in the eastern part,the effect of the earthquake remains. 展开更多
关键词 horizontal movement vertical movement Guanzhong area Wenchuan earthquake Geodynamics GPS(Global Position System)
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Airline Alliance Revenue Distribution Considering Horizontal and Vertical Competition
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作者 Le Meilong Fang Yuan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第S1期20-26,共7页
Considering the existence of multi-level fares in the alliance,and the existence of horizontal competition and vertical competition at the same time,this paper intends to maximize the revenue of airline alliance and f... Considering the existence of multi-level fares in the alliance,and the existence of horizontal competition and vertical competition at the same time,this paper intends to maximize the revenue of airline alliance and fairly distribute the revenue to member airlines.Firstly,a model is built under the centralized mechanism,in which all airlines in the alliance are regarded as a whole.By solving the model,the shadow price of each flight leg on the code-sharing route is gotten.It is used to calculate the proportion of the revenue distribution.Then,the centralized model is decomposed into the single airline model by the proportion.The seat allocation among airlines and distributed revenue can be gotten by solving the model.Three typical examples are designed to test it.The results show that,the model can effectively reflect the managerial principal of the airline alliance,that is maximizing total revenue and fairly distributing the revenue among member airlines. 展开更多
关键词 AIRLINE alliance REVENUE management PROPORTION of REVENUE distribution vertical COMPETITION horizontal COMPETITION
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RULE OF TRANSIENT PHREATIC FLOW SUBJECTED TO VERTICAL AND HORIZONTAL SEEPAGE
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作者 陶月赞 席道瑛 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第1期59-65,共7页
In a semi-infinite aquifer bounded by a channel, a transient flow model is constructed for phreatic water subjected to vertical and horizontal seepage. Based on the first linearized Boussinesq equation, the analytical... In a semi-infinite aquifer bounded by a channel, a transient flow model is constructed for phreatic water subjected to vertical and horizontal seepage. Based on the first linearized Boussinesq equation, the analytical solution of the model is obtained by Laplace transform. Having proven the transformation between the analytical solution and some relevant classic formulas, suitable condition for each of these formulas is demonstrated. On the base of the solution, the variation of transient flow process caused by the variables, such as vertical infiltration intensity, fluctuation range of river stage, aquifer parameters such as transmissivity and specific yield, and the distance from calculating point to channel boundary, are analyzed quantitatively one by one. Lagging effect will happen to the time, when phreatic water gets its maximum fluctuation velocity, response to the varying of the variables stated above. The condition for some variables to form equivalent lagging effect is demonstrated. Corresponding to the mathematical charac teristics of the analytical solution, the physical implication and the fluctuation rule of groundwater level are discussed. 展开更多
关键词 channel boundary semi-infinite aquifer vertical seepage horizontal seepage transient phreatic flow
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INTERACTIONS OF MULTIPLE TYPHOONS AND RELATIONSHIPS OF HORIZONTAL AND VERTICAL VORTICITY
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作者 丁治英 邢蕊 +1 位作者 徐海明 高勇 《Journal of Tropical Meteorology》 SCIE 2017年第1期25-36,共12页
Three typhoons, Goni, Morakot and Etau which were generated in Western Pacific in 2009, are successfully simulated by the WRF model. The horizontal and vertical vorticity and their interaction are analyzed and diagnos... Three typhoons, Goni, Morakot and Etau which were generated in Western Pacific in 2009, are successfully simulated by the WRF model. The horizontal and vertical vorticity and their interaction are analyzed and diagnosed by using the simulation results. It is shown that their resultant vectors had a fixed pattern in the evolution process of the three typhoons: The horizontal vorticity converged to the tropical cyclone(TC) center below 900 h Pa level, flowed out from it at around 900 to 800 h Pa, and flowed in between 800 h Pa and 700 h Pa. If multiple maximum wind speed centers showed up, the horizontal vorticity converged to the center of the typhoon below the maximum wind speed center and diverged from the TC center above the maximum wind speed center. At low levels, the three typhoons interacted with each other through vertical circulation generated by the vortex tube. This circulation was mainly generated by the eastward or westward horizontal vorticity vectors. Clouds and precipitation were generated on the ascending branch of the vertical circulation. The vortex tubes often flowed toward the southwest of the right TC from the northeast of the left TC. According to the full vorticity equation, the horizontal vorticity converted into the vertical vorticity near the maximum wind speed center below 850 h Pa level, and the period of most intense conversion was consistent with the intensification period of TC, while the vorticity advection was against the intensification. The vertical vorticity converted into the horizontal vorticity from 800 h Pa to 600 h Pa, and the wind speed decreased above the maximum wind speed region at low levels. 展开更多
关键词 atmospheric science TYPHOON horizontal and vertical vorticity numerical simulation interaction
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Heat Transfer by Natural Convection from a Vertical and Horizontal Surfaces Using Vertical Fins
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作者 H. R GOSHAYESHI F. AMPOFO 《Energy and Power Engineering》 2009年第2期85-89,共5页
Natural convective heat transfer from a heated horizontal and vertical surfaces directly exposed into air which vertical fins, attached to a surface, project vertically downwards has been numerically studied. It has b... Natural convective heat transfer from a heated horizontal and vertical surfaces directly exposed into air which vertical fins, attached to a surface, project vertically downwards has been numerically studied. It has been assumed that the fins are everywhere at the temperature of the surface. The governing equations, written in dimensionless form, have been solved using the finite element procedure. The results show that vertical plate with vertical fins gives the best performance for natural cooling. 展开更多
关键词 natural CONVECTION horizontal and vertical plate FINS Nusselt number
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On the physical significance and use of a set of horizontal and vertical helicity budget equations
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作者 FU Shenming MAI Zi +1 位作者 SUN Jianhua TANG Huan 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第6期417-423,共7页
For better understanding the variation of helicity and its governing mechanisms,based on the primary momentum equation under the local Cartesian coordinate,a set of horizontal and vertical helicity equations are deriv... For better understanding the variation of helicity and its governing mechanisms,based on the primary momentum equation under the local Cartesian coordinate,a set of horizontal and vertical helicity equations are derived in this study.On this basis,a storm-relative helicity budget equation is derived,the main factors that govern the variation of helicity are discussed,and the key mechanisms underlying the helicity variation are illustrated by using schematic images.Both scale analysis and real case diagnosis are used to compare the relative importance of di erent factors on the variation of helicity.For a meso-α system,it is found that:(i)horizontal helicity is much larger than vertical helicity,and they show signi cantly di erent variation mechanisms;(ii)for the vertical helicity,the vertical perturbation pressure gradient force,buoyancy,the diver-gence-related e ect,and the conversion between vertical and horizontal helicity govern its variation(whereas,the conversion is negligible for the evolution of horizontal helicity);and(iii)baroclinity is crucial for the variation of horizontal helicity,but it is only of secondary importance for the vertical helicity variation. 展开更多
关键词 horizontal helicity vertical helicity baroclinity kinetic energy
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Impacts of Horizontal and Vertical Resolutions on the Microphysical Structure and Boundary Layer Fluxes of Typhoon Hato(2017)
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作者 ZHAO Yang-jie LI Jiang-nan +1 位作者 LI Fang-zhou RUAN Zi-xi 《Journal of Tropical Meteorology》 SCIE 2021年第1期10-23,共14页
We set four sets of simulation experiments to explore the impacts of horizontal resolution(HR)and vertical resolution(VR)on the microphysical structure and boundary layer fluxes of tropical cyclone(TC)Hato(2017).The s... We set four sets of simulation experiments to explore the impacts of horizontal resolution(HR)and vertical resolution(VR)on the microphysical structure and boundary layer fluxes of tropical cyclone(TC)Hato(2017).The study shows that higher HR tends to strengthen TC.Increasing VR in the upper layers tends to weaken TC,while increasing VR in the lower layers tends to strengthen TC.Simulated amounts of all hydrometeors were larger with higher HR.Increasing VR at the upper level enhanced the mixing ratios of cloud ice and cloud snow,while increasing VR at the lower level elevated the mixing ratios of graupel and rainwater.HR has greater impact on the distributions of hydrometeors.Higher HR has a more complete ring structure of the eyewall and more concentrated hydrometeors along the cloud wall.Increasing VR at the lower level has little impact on the distribution of TC hydrometeors,while increasing VR at the upper level enhances the cloud thickness of the eyewall area.Surface latent heat flux(SLHF)is influenced greatly by resolution.Higher HR leads to larger water vapor fluxes and larger latent heat,which would result in a stronger TC.A large amount of false latent heat was generated when HR was too high,leading to an extremely strong TC,VR has a smaller impact on SLHF than HR.But increasing VR at the upper-level reduces the SLHF and weakens TC,and elevating VR at the lower-level increases the SLHF and strengthens TC.The changes in surface water vapor flux and SLHF were practically identical and the simulation results were improved when HR and VR were more coordinated.The friction velocity was greater with higher VR.Enhancing VR at the lower level increased the friction velocity,while increasing VR at the upper level reduced it. 展开更多
关键词 tropical cyclone horizontal resolution vertical resolution WRF
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