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A seismic modeling analysis of wide and narrow 3D observation systems for channel sand bodies 被引量:4
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作者 狄帮让 徐秀仓 魏建新 《Applied Geophysics》 SCIE CSCD 2008年第4期294-300,共7页
The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utili... The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utilize 3D physical seismic modeling experiments. A 3D channel sand body physical seismic model is constructed and two acquisition systems are designed with wide azimuth (16 lines) and narrow azimuth (8 lines) to model 3D seismic data acquisition and processing seismic work flows. From analysis of migrated time slice data with high quality and small size, we conclude that when the overlying layers are smooth and lateral velocities have little change, both wide and narrow azimuth observation systems in 3D acquisition can be used for obtaining high precision imaging and equivalent resolution of the channel sand body. 展开更多
关键词 Wide and narrow azimuth observation systems seismic imaging physicalseismic modeling time slice RESOLUTION
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RBF neural network regression model based on fuzzy observations 被引量:1
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作者 朱红霞 沈炯 苏志刚 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期400-406,共7页
A fuzzy observations-based radial basis function neural network (FORBFNN) is presented for modeling nonlinear systems in which the observations of response are imprecise but can be represented as fuzzy membership fu... A fuzzy observations-based radial basis function neural network (FORBFNN) is presented for modeling nonlinear systems in which the observations of response are imprecise but can be represented as fuzzy membership functions. In the FORBFNN model, the weight coefficients of nodes in the hidden layer are identified by using the fuzzy expectation-maximization ( EM ) algorithm, whereas the optimal number of these nodes as well as the centers and widths of radial basis functions are automatically constructed by using a data-driven method. Namely, the method starts with an initial node, and then a new node is added in a hidden layer according to some rules. This procedure is not terminated until the model meets the preset requirements. The method considers both the accuracy and complexity of the model. Numerical simulation results show that the modeling method is effective, and the established model has high prediction accuracy. 展开更多
关键词 radial basis function neural network (RBFNN) fuzzy membership function imprecise observation regression model
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3D Geometry-Based UAV-MIMO Channel Modeling and Simulation 被引量:15
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作者 Rubing Jia Yiran Li +1 位作者 Xiang Cheng Bo Ai 《China Communications》 SCIE CSCD 2018年第12期64-74,共11页
A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) ... A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) channel is proposed in this paper. The channel characteristics, including space-time correlation function(STCF), Doppler power spectral density(DPSD), level crossing rate(LCR) and average fade duration(AFD), are derived based on the single sphere reference model for a non-isotropic environment. The corresponding sum-of-sinusoids(SoS) simulation models including both the deterministic model and statistical model with finite scatterers are also proposed for practicable implementation. The simulation results illustrate that the simulation models well reproduce the channel characteristics of the single sphere reference model with sufficient simulation scatterers. And the statistical model has a better approximation of the reference model in comparison with the deterministic one when the simulation trials of the stochastic model are sufficient. The effects of the parameters such as flight height, moving direction and Rice factor on the characteristics are also studied. 展开更多
关键词 UAV-MIMO geometry-based model CHANNEL CHARACTERISTICS simulation model
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The in situ observation of modelled sea ice drift characteristics in the Bohai Sea 被引量:5
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作者 Yu Yan Wei Gu +1 位作者 Yingjun Xu Qian Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第3期17-25,共9页
Sea ice drift is mainly controlled by ocean currents, local wind, and internal ice stress. Information on sea ice motion, especially in situ synchronous observation of an ice velocity, a current velocity, and a wind s... Sea ice drift is mainly controlled by ocean currents, local wind, and internal ice stress. Information on sea ice motion, especially in situ synchronous observation of an ice velocity, a current velocity, and a wind speed, is of great significance to identify ice drift characteristics. A sea ice substitute, the so-called "modelled ice", which is made by polypropylene material with a density similar to Bohai Sea ice, is used to complete a free drift experiment in the open sea. The trajectories of isolated modelled ice, currents and wind in the Bohai Sea during non-frozen and frozen periods are obtained. The results show that the currents play a major role while the wind plays a minor role in the free drift of isolated modelled ice when the wind is mild in the Bohai Sea. The modelled ice drift is significantly affected by the ocean current and wind based on the ice–current–wind relationship established by a multiple linear regression. The modelled ice velocity calculated by the multiple linear regression is close to that of the in situ observation, the magnitude of the error between the calculated and observed ice velocities is less than12.05%, and the velocity direction error is less than 6.21°. Thus, the ice velocity can be estimated based on the observed current velocity and wind speed when the in situ observed ice velocity is missing. And the modelled ice of same thickness with a smaller density is more sensitive to the current velocity and the wind speed changes. In addition, the modelled ice drift characteristics are shown to be close to those of the real sea ice, which indicates that the modelled ice can be used as a good substitute of real ice for in situ observation of the free ice drift in the open sea, which helps solve time availability, safety and logistics problems related to in situ observation on real ice. 展开更多
关键词 Bohai SEA modelled ICE in SITU observation SEA ICE DRIFT
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Experimental Model and Analytic Solution for Real-time Observation of Vehicle's Additional Steer Angle 被引量:3
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作者 ZHANG Xiaolong LI Liang +2 位作者 PAN Deng CAO Chengmao SONG Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期340-347,共8页
The current research of real-time observation for vehicle roll steer angle and compliance steer angle(both of them comprehensively referred as the additional steer angle in this paper) mainly employs the linear vehi... The current research of real-time observation for vehicle roll steer angle and compliance steer angle(both of them comprehensively referred as the additional steer angle in this paper) mainly employs the linear vehicle dynamic model, in which only the lateral acceleration of vehicle body is considered. The observation accuracy resorting to this method cannot meet the requirements of vehicle real-time stability control, especially under extreme driving conditions. The paper explores the solution resorting to experimental method. Firstly, a multi-body dynamic model of a passenger car is built based on the ADAMS/Car software, whose dynamic accuracy is verified by the same vehicle's roadway test data of steady static circular test. Based on this simulation platform, several influencing factors of additional steer angle under different driving conditions are quantitatively analyzed. Then ε-SVR algorithm is employed to build the additional steer angle prediction model, whose input vectors mainly include the sensor information of standard electronic stability control system(ESC). The method of typical slalom tests and FMVSS 126 tests are adopted to make simulation, train model and test model's generalization performance. The test result shows that the influence of lateral acceleration on additional steer angle is maximal (the magnitude up to 1°), followed by the longitudinal acceleration-deceleration and the road wave amplitude (the magnitude up to 0.3°). Moreover, both the prediction accuracy and the calculation real-time of the model can meet the control requirements of ESC This research expands the accurate observation methods of the additional steer angle under extreme driving conditions. 展开更多
关键词 VEHICLE ADAMS model additional steer SVM real-time observation
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ASYMPTOTIC NORMALITY OF PARAMETERSESTIMATION IN EV MODEL WITH REPLICATEDOBSERVATIONS 被引量:3
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作者 张三国 陈希孺 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期107-114,共8页
This paper based on the essay [1], studies in case that replicated observations are available in some experimental points., the parameters estimation of one dimensional linear errors-in-variables (EV) models. Asymptot... This paper based on the essay [1], studies in case that replicated observations are available in some experimental points., the parameters estimation of one dimensional linear errors-in-variables (EV) models. Asymptotic normality is established. 展开更多
关键词 errors-in-variables model asymptotic normality replicated observations
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Evaluation of Simulated CO_2 Concentrations from the CarbonTracker-Asia Model Using In-situ Observations over East Asia for 2009–2013 被引量:2
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作者 Samuel Takele KENEA Young-Suk OH +6 位作者 Jae-Sang RHEE Tae-Young GOO Young-Hwa BYUN Shanlan LI Lev D.LABZOVSKII Haeyoung LEE Robert F.BANKS 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第6期603-613,共11页
The CarbonTracker(CT) model has been used in previous studies for understanding and predicting the sources, sinks, and dynamics that govern the distribution of atmospheric CO_2 at varying ranges of spatial and tempora... The CarbonTracker(CT) model has been used in previous studies for understanding and predicting the sources, sinks, and dynamics that govern the distribution of atmospheric CO_2 at varying ranges of spatial and temporal scales. However, there are still challenges for reproducing accurate model-simulated CO_2 concentrations close to the surface, typically associated with high spatial heterogeneity and land cover. In the present study, we evaluated the performance of nested-grid CT model simulations of CO_2 based on the CT2016 version through comparison with in-situ observations over East Asia covering the period 2009–13. We selected sites located in coastal, remote, inland, and mountain areas. The results are presented at diurnal and seasonal time periods. At target stations, model agreement with in-situ observations was varied in capturing the diurnal cycle. Overall, biases were less than 6.3 ppm on an all-hourly mean basis, and this was further reduced to a maximum of 4.6 ppm when considering only the daytime. For instance, at Anmyeondo, a small bias was obtained in winter, on the order of 0.2 ppm. The model revealed a diurnal amplitude of CO_2 that was nearly flat in winter at Gosan and Anmyeondo stations, while slightly overestimated in the summertime. The model's performance in reproducing the diurnal cycle remains a challenge and requires improvement. The model showed better agreement with the observations in capturing the seasonal variations of CO_2 during daytime at most sites, with a correlation coefficient ranging from 0.70 to 0.99. Also, model biases were within-0.3 and 1.3 ppm, except for inland stations(7.7 ppm). 展开更多
关键词 model EVALUATION in-situ observations CarbonTracker EAST ASIA
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Design of task priority model and algorithm for imaging observation problem 被引量:3
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作者 WU Jian LU Fang +2 位作者 ZHANG Jiawei YANG Jinghui XING Lining 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第2期321-334,共14页
In the imaging observation system, imaging task scheduling is an important topic. Most scholars study the imaging task scheduling from the perspective of static priority, and only a few from the perspective of dynamic... In the imaging observation system, imaging task scheduling is an important topic. Most scholars study the imaging task scheduling from the perspective of static priority, and only a few from the perspective of dynamic priority. However,the priority of the imaging task is dynamic in actual engineering. To supplement the research on imaging observation, this paper proposes the task priority model, dynamic scheduling strategy and Heuristic algorithm. At first, this paper analyzes the relevant theoretical basis of imaging observation, decomposes the task priority into four parts, including target priority, imaging task priority, track, telemetry & control(TT&C)requirement priority and data transmission requirement priority, summarizes the attribute factors that affect the above four types of priority in detail, and designs the corresponding priority model. Then, this paper takes the emergency tasks scheduling problem as the background, proposes the dynamic scheduling strategy and heuristic algorithm. Finally, the task priority model,dynamic scheduling strategy and heuristic algorithm are verified by experiments. 展开更多
关键词 IMAGING observation system IMAGING TASK PRIORITY TASK PRIORITY model dynamic SCHEDULING strategy HEURISTIC algorithm
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Pattern-Moving-Based Parameter Identification of Output Error Models with Multi-Threshold Quantized Observations 被引量:2
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作者 Xiangquan Li Zhengguang Xu +1 位作者 Cheng Han Ning Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1807-1825,共19页
This paper addresses a modified auxiliary model stochastic gradient recursive parameter identification algorithm(M-AM-SGRPIA)for a class of single input single output(SISO)linear output error models with multi-thresho... This paper addresses a modified auxiliary model stochastic gradient recursive parameter identification algorithm(M-AM-SGRPIA)for a class of single input single output(SISO)linear output error models with multi-threshold quantized observations.It proves the convergence of the designed algorithm.A pattern-moving-based system dynamics description method with hybrid metrics is proposed for a kind of practical single input multiple output(SIMO)or SISO nonlinear systems,and a SISO linear output error model with multi-threshold quantized observations is adopted to approximate the unknown system.The system input design is accomplished using the measurement technology of random repeatability test,and the probabilistic characteristic of the explicit metric value is employed to estimate the implicit metric value of the pattern class variable.A modified auxiliary model stochastic gradient recursive algorithm(M-AM-SGRA)is designed to identify the model parameters,and the contraction mapping principle proves its convergence.Two numerical examples are given to demonstrate the feasibility and effectiveness of the achieved identification algorithm. 展开更多
关键词 Pattern moving multi-threshold quantized observations output error model auxiliary model parameter identification
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Preliminary results on kinematic model of tectonic blocks derived from high precision GPS observations in Southwest China 被引量:1
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作者 黄立人 马青 +2 位作者 朱文耀 程宗颐 熊永清 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第1期27-34,共8页
In the paper, the kinematic model of tectonic blocks in southwest China is studied based on the precision GPS observations carried out under the major subject of 'Studies on Current Crustal Movement and Geodynamic... In the paper, the kinematic model of tectonic blocks in southwest China is studied based on the precision GPS observations carried out under the major subject of 'Studies on Current Crustal Movement and Geodynamics' which belongs to the State Climbing Project. It is believed that at present, the data of high precision GPS observation may provide convincing information related to the horizontal movement of tectonic blocks in the Chinese mainland. The preliminary results obtained from the kinematic model have given some direct evidences for the research of dynamic mechanism of crustal deformation in the Chinese mainland and on the basis of which, the kinematic characteristics and their relations to the seismicity and seismic risk in the reobserved region are analysed. The preliminary observation results are encouraging. 展开更多
关键词 GPS observation Southwest China tectonic block kinematic model
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Modified Observation Model in Tightly-Coupled INS/GPS Integration 被引量:1
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作者 Guochao Fan Dan Song Chengdong Xu 《Journal of Beijing Institute of Technology》 EI CAS 2017年第1期16-28,共13页
The conventional Kalman filter(CKF)is widely used in tightly-coupled INS/GPS integrated navigation systems.The linearization accuracy of the CKF observation model is one of the decisive factors of the estimation acc... The conventional Kalman filter(CKF)is widely used in tightly-coupled INS/GPS integrated navigation systems.The linearization accuracy of the CKF observation model is one of the decisive factors of the estimation accuracy and therefore navigation accuracy.Additionally,the conventional observation model(COM)used by the filter may be divergent,which would result into some terrible accuracies of INS/GPS integration navigation in some cases.To improve the navigation accuracy,the linearization accuracy of the COM still needs further improvement.To deal with this issue,the observation model is modified with the linearization of the range and range rate equations in this paper.Compared with COM,the modified observation model(MOM)further considers the difference between the real user position and the position calculated by SINS.To verify the advantages of this model,INS/GPS integrated navigation simulation experiments are conducted with the usage of COM and MOM respectively.According to the simulation results,the positions(velocities)calculated using COM are divergent over time while the others using MOM are convergent,which demonstrates the higher linearization accuracy of MOM. 展开更多
关键词 INS/GPS integration LINEARIZATION modified observation model (MOM) conventionalobservation model (COM)
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Quantum Realities and Observer-Dependent Universes: An Advanced Observer Model
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作者 Joseph Hon Cheung Wong 《Journal of Quantum Information Science》 CAS 2024年第3期69-121,共53页
This paper presents a novel observer model that integrates quantum mechanics, relativity, idealism, and the simulation hypothesis to explain the quantum nature of the universe. The model posits a central server transm... This paper presents a novel observer model that integrates quantum mechanics, relativity, idealism, and the simulation hypothesis to explain the quantum nature of the universe. The model posits a central server transmitting multi-media frames to create observer-dependent realities. Key aspects include deriving frame rates, defining quantum reality, and establishing hierarchical observer structures. The model’s impact on quantum information theory and philosophical interpretations of reality are examined, with detailed discussions on information loss and recursive frame transmission in the appendices. 展开更多
关键词 Quantum Mechanics observer model Frame Rates Quantum Reality Hierarchical observers Information Theory Simulation Hypothesis Recursive Frame Transmission Information Loss
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A 3D Geometry-Based Scattering Model for Vehicleto-Vehicle Wideband MIMO Relay-Based Cooperative Channels 被引量:1
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作者 Xiaolin Liang Xiongwen Zhao +2 位作者 Shu Li Qi Wang Wenbing Lu 《China Communications》 SCIE CSCD 2016年第10期1-10,共10页
In this paper, a three-dimensional(3D) geometry- based stochastic scattering model(GBSSM) for wideband multi-input multi-output(MIMO) vehicle-to-vehicle(V2V) relay-based cooperative fading channel based on geometrical... In this paper, a three-dimensional(3D) geometry- based stochastic scattering model(GBSSM) for wideband multi-input multi-output(MIMO) vehicle-to-vehicle(V2V) relay-based cooperative fading channel based on geometrical three-cylinder is proposed. Non-line-of-sight(NLOS) propagation condition is assumed in amplify-and-forward(AF) cooperative networks from the source mobile station(S) to the destination mobile station(D) via the mobile relay station(R). We extend the proposed narrowband model to wideband and also introduce the carrier frequency and bandwidth into the model. To avoid complicated procedure in deriving the analytical expressions of the channel parameters and functions, the channel is realized first. By using the realized channel matrix, the channel properties are further investigated. 展开更多
关键词 geometry-based scattering model MIMO relay-based cooperative communication vehicle-to-vehicle(V2V) WIDEBAND
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Integrating Quantum Mechanics and the Advanced Observer Model: A New Paradigm for Reality Construction
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作者 Joseph H. C. Wong 《Journal of Quantum Information Science》 2024年第4期158-195,共38页
This paper introduces a groundbreaking synthesis of fundamental quantum mechanics with the Advanced Observer Model (AOM), presenting a unified framework that reimagines the construction of reality. AOM highlights the ... This paper introduces a groundbreaking synthesis of fundamental quantum mechanics with the Advanced Observer Model (AOM), presenting a unified framework that reimagines the construction of reality. AOM highlights the pivotal role of the observer in shaping reality, where classical notions of time, space, and energy are reexamined through the quantum lens. By engaging with key quantum equations—such as the Schrödinger equation, Heisenberg uncertainty principle, and Dirac equation—the paper demonstrates how AOM unifies the probabilistic nature of quantum mechanics with the determinism of classical physics. Central to this exploration is the Sequence of Quantum States (SQS) and Constant Frame Rate (CFR), which align with concepts like quantum superposition, entanglement, and wave function collapse. The model’s implications extend to how observers perceive reality, proposing that interference patterns between wave functions form the foundation of observable phenomena. By offering a fresh perspective on the interplay between determinacy and indeterminacy, AOM lays a robust theoretical foundation for future inquiry into quantum physics and the philosophy of consciousness. 展开更多
关键词 Advanced observer model (AOM) Quantum Mechanics Reality Construction Sequence of Quantum States (SQS) Constant Frame Rate (CFR) Wave Function Collapse Quantum Superposition Quantum Entanglement observer Effect Determinacy vs. Indeterminacy ħ/CFR model
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Bridging Classical and Quantum Realms: The Conceptual and Theoretical Framework of the Advanced Observer Model
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作者 Joseph H. C. Wong 《Journal of Quantum Information Science》 2024年第4期123-157,共35页
This paper presents the Advanced Observer Model (AOM), a groundbreaking conceptual framework designed to clarify the complex and often enigmatic nature of quantum mechanics. The AOM serves as a metaphorical lens, brin... This paper presents the Advanced Observer Model (AOM), a groundbreaking conceptual framework designed to clarify the complex and often enigmatic nature of quantum mechanics. The AOM serves as a metaphorical lens, bringing the elusive quantum realm into sharper focus by transforming its inherent uncertainty into a coherent, structured ‘Frame Stream’ that aids in the understanding of quantum phenomena. While the AOM offers conceptual simplicity and clarity, it recognizes the necessity of a rigorous theoretical foundation to address the fundamental uncertainties that lie at the core of quantum mechanics. This paper seeks to illuminate those theoretical ambiguities, bridging the gap between the abstract insights of the AOM and the intricate mathematical foundations of quantum theory. By integrating the conceptual clarity of the AOM with the theoretical intricacies of quantum mechanics, this work aspires to deepen our understanding of this fascinating and elusive field. 展开更多
关键词 Advanced observer model AOM DETERMINACY INDETERMINACY Reverse Engineering observer-observed Interaction Quantum Wave Function Probability Density Function PDF Probability Space Potential Space Quantum Computing Quantum Information Processing Static Configuration SC Dynamic Configuration DC Sequence of Quantum States SQS Perceptual Sequence of observations PSO Theory of Relativity Lorentz Transformation
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Towards a Unified Theory of Everything: Integrating Discrete Time Evolution and Classical-Quantum Dynamics in the Advanced Observer Model (AOM)
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作者 Joseph H. C. Wong 《Journal of Quantum Information Science》 2024年第4期196-233,共38页
This paper introduces the Advanced Observer Model (AOM), a novel framework that integrates classical mechanics, quantum mechanics, and relativity through the observer’s role in constructing reality. Central to the AO... This paper introduces the Advanced Observer Model (AOM), a novel framework that integrates classical mechanics, quantum mechanics, and relativity through the observer’s role in constructing reality. Central to the AOM is the Static Configuration/Dynamic Configuration (SC/DC) conjugate, which examines physical systems through the interaction between static spatial configurations and dynamic quantum states. The model introduces a Constant Frame Rate (CFR) to quantize time perception, providing a discrete model for time evolution in quantum systems. By modifying the Schrödinger equation with CFR, the AOM bridges quantum and classical physics, offering a unified interpretation where classical determinism and quantum uncertainty coexist. A key feature of the AOM is its energy scaling model, where energy grows exponentially with spatial dimensionality, following the relationshipE∝(π)n. This dimensional scaling connects the discrete time perception of the observer with both quantum and classical energy distributions, providing insights into the nature of higher-dimensional spaces. Additionally, the AOM posits that spacetime curvature arises from quantum interactions, shaped by the observer’s discrete time perception. The model emphasizes the observer’s consciousness as a co-creator of reality, offering new approaches to understanding the quantum-classical transition. While speculative, the AOM opens new avenues for addressing foundational questions in quantum mechanics, relativity, dimensionality, and the nature of reality. 展开更多
关键词 Quantum Mechanics Schrödinger Equation Constant Frame Rate (CFR) Advanced observer model (AOM) Relativistic Physics Classical-Quantum Transition Wave Function Discrete Time Evolution Spacetime Geometry Unified Theory Quantum-Classical Unification observer-Dependent Reality Energy Scaling
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Observations of Passenger Flow and Verification of a Crowd Dynamics Model
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作者 YUAN Jianping FANG Zheng +2 位作者 LO Siuming XIE Lilin HUANG Danguang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第2期195-200,共6页
This paper reports observations of passenger flow in the Wuchang railway station in Wuhan, China during the Chinese Traditional Spring Festival in 2006. The data collected are used to verify a crowd dynamics model pre... This paper reports observations of passenger flow in the Wuchang railway station in Wuhan, China during the Chinese Traditional Spring Festival in 2006. The data collected are used to verify a crowd dynamics model previously developed. The crowd dynamics model is based on simulating the global movement of each individual under the influence of the surrounding crowd, and the good agreement between the predictions and observations validates the prediction model. The crowd dynamics model suggests that the crowd movement speed is dominated by two factors: the front-back inter-person effect, and the pedestrian's self-motive. The first effect gives logarithmic relationship between the crowd speed and crowd density. The second factor depends on the individual motive driven with which people try to divorce themselves from the control of the crowd movement. The prediction model are helpful to guide the design of public traffic systems for effective crowd dispersal. 展开更多
关键词 crowd dynamics model observation mathematical modeling EVACUATION traffic planning
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基于Observation Nudging高精度深远海风资源模拟方法研究
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作者 吴春雷 王尼娜 +3 位作者 赵岩 黄伟 董雪 刘树洁 《能源工程》 2024年第6期107-115,共9页
为提升深远海区域风资源评估的准确性,将Observation Nudging方法应用于中尺度气象模型WRF中,通过同化多个近海激光雷达数据来改进风速模拟效果。通过对比未同化的CTRL模型、常用的Grid Nudging方法(GN模型)和Observation Nudging方法(O... 为提升深远海区域风资源评估的准确性,将Observation Nudging方法应用于中尺度气象模型WRF中,通过同化多个近海激光雷达数据来改进风速模拟效果。通过对比未同化的CTRL模型、常用的Grid Nudging方法(GN模型)和Observation Nudging方法(ON模型),系统评估了ON模型在风速模拟、风廓线精度及风能密度估算方面的优势。研究表明,ON模型显著提升了5%的风速模拟相关性,并降低了均方根误差和平均绝对误差。此外,ON模型在风力机关键运行高度(50m~150m)区域风廓线的模拟精度较高,并在风能密度评估中较CTRL模型误差降低了3%。尽管Observation Nudging能有效提升局地模拟精度,但对近海表面风廓线的物理约束能力有待改进。其次,GN模型在小尺度特征刻画上存在不足,因而不适合用于风资源的细化分析。总之,ON模型在缺乏观测的深远海区域具有较强的工程应用潜力,可为风电场合理规划提供有力支持。 展开更多
关键词 深远海风资源评估 WRF模式 ON模型 GN模型 风模拟
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Experimental Observation of the Ground-State Geometric Phase of Three-Spin XY Model
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作者 周辉 李兆凯 +3 位作者 王恒岩 陈宏伟 彭新华 杜江峰 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期1-5,共5页
The geometric phase has become a fundamental concept in many fields of physics since it was revealed. Recently, the study of the geometric phase has attracted considerable attention in the context of quantum phase tra... The geometric phase has become a fundamental concept in many fields of physics since it was revealed. Recently, the study of the geometric phase has attracted considerable attention in the context of quantum phase transition, where the ground state properties of the system experience a dramatic change induced by a variation of an external parameter. In this work, we experimentally measure the ground-state geometric phase of the three-spin XY model by utilizing the nuclear magnetic resonance technique. The experimental results indicate that the geometric phase could be used as a fingerprint of the ground-state quantum phase transition of many-body systems. 展开更多
关键词 of on it in Experimental observation of the Ground-State Geometric Phase of Three-Spin XY model is been that
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Applying the Distributed Hydrological Model for Tropical Monsoon Basins by Using Earth Observation Data (Case Studies: Kone and Ba River Basins)
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作者 Phan Thi Thanh Hang 《Journal of Geoscience and Environment Protection》 2019年第1期23-37,共15页
Due to the limitation of data sources, the application of Distributed Hydrological Models (DHMs) using earth observation data to research water resources is necessary. In this study, the BTOPMC (Block-wise use of TOPM... Due to the limitation of data sources, the application of Distributed Hydrological Models (DHMs) using earth observation data to research water resources is necessary. In this study, the BTOPMC (Block-wise use of TOPMODEL) model was applied for 2 basins in the tropical monsoon region. This is the first time that the land cover map of the CCI (Climate Change Initiative Land Cover Team) was prepared for input data instead of IGBP (International Geosphere-Biosphere Programme) land cover map as proposed in the demo version of the BTOPMC model. The calibration and validation results showed that the Nash-Sutcliffe coefficients for daily stream discharge were 77.5% and 68.7% at Cung Son station (Ba basin). The Nash-Sutcliffe coefficients for daily stream discharge were 79.4% and 69.0% at Binh Tuong station (Kone basin), respectively. Because of a stop in measuring the discharge at Binh Tuong station in 2007, this model was applied to simulate discharge during the period of 2008-2015. Furthermore, the effect of land cover on discharge at Cung Son station was considered. The annual discharge in 2010 at Cung Son decreased 8 m3/s in the comparison between two scenarios (land cover of 2000 and 2010). According to this result, it is possible to propose a wide application range of the DHMs model to the tropical monsoon river basins using earth observation data. 展开更多
关键词 Distributed HYDROLOGICAL model TROPICAL MONSOON DISCHARGE Land COVER Earth observation Data
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