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关于日文汉字“行”字的唐音考察 被引量:4
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作者 张升余 《外语教学》 CSSCI 北大核心 2011年第4期41-46,共6页
日文汉字"行"字的唐音"アン(an)"无声母,这个音究竟是[xing]还是[hng?]通过唐音资料考察,结合中国语音韵变化进行对比分析得出结论:1)"行"字「アン」是中世唐音。它是浙江方言庚韵音,不是唐韵... 日文汉字"行"字的唐音"アン(an)"无声母,这个音究竟是[xing]还是[hng?]通过唐音资料考察,结合中国语音韵变化进行对比分析得出结论:1)"行"字「アン」是中世唐音。它是浙江方言庚韵音,不是唐韵a音;2)近世唐音的音韵系统与中世唐音区分明显,中世唐音以浙江方言为主;近世唐音以南京官话为主;3)明清以前浙江方言保留中古音,匣母字均呈现零声母;4)宋代浙江方言音中白话读开口,文言读齐齿的现象比较明显。 展开更多
关键词 “行”字 中世唐音 近世唐音 零声母
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THREE-DIMENSIONAL TRAJECTORY OPTIMIZATION WITH DIRECT METHOD 被引量:1
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作者 沈春林 刘国刚 +1 位作者 吴文海 李丽荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期118-122,共5页
The principle of direct method used in optimal control problem is introduced. Details of applying this method to flight trajectory generation are presented including calculation of velocity and controls histories. And... The principle of direct method used in optimal control problem is introduced. Details of applying this method to flight trajectory generation are presented including calculation of velocity and controls histories. And capabilities of flight and propulsion systems are considered also. Combined with digital terrain map technique, the direct method is applied to the three dimensional trajectory optimization for low altitude penetration, and simplex algorithm is used to solve the parameters in optimization. For the small number of parameters, the trajectory can be optimized in real time on board. 展开更多
关键词 direct optimization method trajectory optimization low altitude penetration simplex algorithm
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Evaluation of fatigue property of asphalt mixtures based on digital image correlation method 被引量:6
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作者 蒋继望 倪富健 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期216-223,共8页
In order to evaluate the accumulative of tensile strain in the process of fatigue failure, the digital image correlation(DIC) method was utilized to characterize the tensile strain development of asphalt mixtures in... In order to evaluate the accumulative of tensile strain in the process of fatigue failure, the digital image correlation(DIC) method was utilized to characterize the tensile strain development of asphalt mixtures in the indirect tensile(IDT)fatigue test. Three typical hot mix asphalt(HMA) mixtures with varying nominal maximum aggregate sizes were tested at four stress levels. During the tests, a digital camera was mounted to capture the displacement/strain fields on the surface of the specimen by recording the real-time change of speckle position. The results indicate that the vertical deformation curve can barely evaluate the fatigue performance accurately due to the non-negligible local deflection near the loading point. However, based on the analysis of strain fields,the optimal fatigue cracking zone is determined as a 40mm×40mm rectangle in the middle of the specimens. Also, a reasonable fatigue model based on the tensile strain curves calculated by DIC is proposed to predict the fatigue lives of asphalt mixtures. 展开更多
关键词 asphalt mixtures fatigue behavior digital image correlation indirect tensile fatigue test
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Hysteresis model of magnetostrictive actuators and its numerical realization 被引量:3
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作者 TANG Zhi-feng LV Fu-zai XIANG Zhan-qin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第7期1059-1064,共6页
This paper presents two numerical realization of Preisach model by Density Function Method (DFM) and F Function Method (FFM) for a giant magnetostrictive actuator (GMA). Experiment and simulation showed that FFM is be... This paper presents two numerical realization of Preisach model by Density Function Method (DFM) and F Function Method (FFM) for a giant magnetostrictive actuator (GMA). Experiment and simulation showed that FFM is better than DFM for predicting precision of hysteresis loops. Lagrange bilinear interpolation algorithm is used in Preisach numerical realization to enhance prediction performance. A set of hysteresis loops and higher order reversal curves are predicted and experimentally verified. The good agreement between the measured and predicted curves shows that the classical Preisach model is effective for modelling the quasi-static hysteresis of the GMA. 展开更多
关键词 MAGNETOSTRICTIVE ACTUATOR HYSTERESIS Density Function Method (DFM) F Function Method (FFM)
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Theoretical and Experimental Study on Ground Coupled Heat Pump with Vertical Spiral Coil 被引量:4
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作者 李新国 周倩 +2 位作者 赵军 朱强 胡璟 《Transactions of Tianjin University》 EI CAS 2003年第2期123-126,共4页
The numeric al simulation study on the temperature distribution of underground field for the ground coupled heat pump (GCHP) with vertical spira l coil was carried out by using finite element. The distribution and rec... The numeric al simulation study on the temperature distribution of underground field for the ground coupled heat pump (GCHP) with vertical spira l coil was carried out by using finite element. The distribution and recovery of undergroun d field temperature under different operation ratio and the optimal operation ratio were simulated.The performance parameters, i.e. inlet and outlet temperature of the ground spiral coil in heating and cooling modes were tested, the heat extracted or emitted by the heat pump to the ground was calculated, and the coefficients of performance (COP) of GCHP at heat ing and cooling modes were analyzed. 展开更多
关键词 ground coupled heat pump (GCHP) vert ic al spiral coil underground temperature distribution optimal operation ratio
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Vector form Intrinsic Finite Element Method for the Two-Dimensional Analysis of Marine Risers with Large Deformations 被引量:3
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作者 LI Xiaomin GUO Xueli GUO Haiyan 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期498-506,共9页
Robust numerical models that describe the complex behaviors of risers are needed because these constitute dynamically sensitive systems. This paper presents a simple and efficient algorithm for the nonlinear static an... Robust numerical models that describe the complex behaviors of risers are needed because these constitute dynamically sensitive systems. This paper presents a simple and efficient algorithm for the nonlinear static and dynamic analyses of marine risers. The proposed approach uses the vector form intrinsic finite element(VFIFE) method, which is based on vector mechanics theory and numerical calculation. In this method, the risers are described by a set of particles directly governed by Newton's second law and are connected by weightless elements that can only resist internal forces. The method does not require the integration of the stiffness matrix, nor does it need iterations to solve the governing equations. Due to these advantages, the method can easily increase or decrease the element and change the boundary conditions, thus representing an innovative concept of solving nonlinear behaviors, such as large deformation and large displacement. To prove the feasibility of the VFIFE method in the analysis of the risers, rigid and flexible risers belonging to two different categories of marine risers, which usually have differences in modeling and solving methods, are employed in the present study. In the analysis, the plane beam element is adopted in the simulation of interaction forces between the particles and the axial force, shear force, and bending moment are also considered. The results are compared with the conventional finite element method(FEM) and those reported in the related literature. The findings revealed that both the rigid and flexible risers could be modeled in a similar unified analysis model and that the VFIFE method is feasible for solving problems related to the complex behaviors of marine risers. 展开更多
关键词 marine riser vector form intrinsic finite element (VFIFE) static analysis dynamic analysis geometric nonlinearity
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Analysis of steel-concrete composite structure with overlap slab of Xingguang bridge 被引量:5
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作者 叶梅新 黄琼 吴芹芹 《Journal of Central South University of Technology》 EI 2007年第1期120-124,共5页
Finite element modeling methods of steel-concrete composite structure with overlap slab were investigated. A two-step finite element method was presented. It was applied to analyze an extra long span composite bridge.... Finite element modeling methods of steel-concrete composite structure with overlap slab were investigated. A two-step finite element method was presented. It was applied to analyze an extra long span composite bridge. The conversion of structure system and the mechanical behavior of the bridge were analyzed with two different construction methods. The stresses of steel beams, precast slabs and in-situ-place concrete under the total load were compared. The results show that steel-concrete composite structure with overlap slab has many advantages, the construction method that the top in-situ concrete and the concrete in construction joints are cast respectively is rather reasonable than the one that the top in-situ concrete and the concrete in construction joints are cast at the same time, and the two-step finite element method is affective to such large-scale structures. 展开更多
关键词 composite structure numerical method two-step finite element method mechanical behavior
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Neighborhood fusion-based hierarchical parallel feature pyramid network for object detection 被引量:3
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作者 Mo Lingfei Hu Shuming 《Journal of Southeast University(English Edition)》 EI CAS 2020年第3期252-263,共12页
In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid... In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid network(FPN)and deconvolutional single shot detector(DSSD),where the bottom layer of the feature pyramid network relies on the top layer,NFPN builds the feature pyramid network with no connections between the upper and lower layers.That is,it only fuses shallow features on similar scales.NFPN is highly portable and can be embedded in many models to further boost performance.Extensive experiments on PASCAL VOC 2007,2012,and COCO datasets demonstrate that the NFPN-based SSD without intricate tricks can exceed the DSSD model in terms of detection accuracy and inference speed,especially for small objects,e.g.,4%to 5%higher mAP(mean average precision)than SSD,and 2%to 3%higher mAP than DSSD.On VOC 2007 test set,the NFPN-based SSD with 300×300 input reaches 79.4%mAP at 34.6 frame/s,and the mAP can raise to 82.9%after using the multi-scale testing strategy. 展开更多
关键词 computer vision deep convolutional neural network object detection hierarchical parallel feature pyramid network multi-scale feature fusion
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Digital Forensic Analysis on Runtime Instruction Flow
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作者 Li Juanru Gu Dawu Deng Chaoguo Luo Yuhao 《China Communications》 SCIE CSCD 2010年第6期112-119,共8页
Computer system's runtime information is an essential part of the digital evidence. Current digital forensic approaches mainly focus on memory and I/O data, while the runtime instructions from processes are often ign... Computer system's runtime information is an essential part of the digital evidence. Current digital forensic approaches mainly focus on memory and I/O data, while the runtime instructions from processes are often ignored. We present a novel approach on runtime instruction forensic analysis and have developed a forensic system which collects instruction flow and extracts digital evidence. The system is based on whole-system emulation technique and analysts are allowed to define analysis strategy to improve analysis efficiency and reduce overhead. This forensic approach and system are applicable to binary code analysis, information retrieval and matware forensics. 展开更多
关键词 digital forensics dynamic analysis instruction flow virtual machine EMULATION
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Energy Efficient Multi-Antenna UAV-Enabled Mobile Relay 被引量:8
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作者 Qingheng Song Fuchun Zheng 《China Communications》 SCIE CSCD 2018年第5期41-50,共10页
In this paper, we study an energy efficient multi-antenna unmanned aerial vehicle(UAV)-enabled half-duplex mobile relaying system under Rician fading channels. By assuming that the UAV follows a circular trajectory at... In this paper, we study an energy efficient multi-antenna unmanned aerial vehicle(UAV)-enabled half-duplex mobile relaying system under Rician fading channels. By assuming that the UAV follows a circular trajectory at fixed altitude and applying the decode-and-forward relaying strategy, we maximize the energy efficiency by jointly designing beamforming, power allocation, circular radius and flight speed, subject to the sum transmit power constraint on source node and UAV relay node. First, we maximize the end-to-end signal-to-noise ratio by jointly designing beamforming and statistical power allocation. Based on the obtained beamforming and power allocation results, we then obtain a semi closed-form expression of energy efficiency, and finally maximize energy efficiency by optimizing flight speed and circular radius, allowing optimal circular radius to be obtained via numerical computation. Numerical results demonstrate that the proposed scheme can effectively enhance the system energy efficiency. 展开更多
关键词 UAV mobile relay energy efficiency statistical power allocation circular radius flight speed
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日语常用汉字与汉语现行汉字比较
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作者 石黑章予 《语言历史论丛》 2013年第1期254-275,共22页
日本《常用汉字表》在2010年有了修改,因为颁布不久,所以至今日本《常用汉字表》和中国《现代汉语常用字表》的对比研究都是依据1981年颁布的《常用汉字表》中的1945个汉字。本文依据日本《常用汉字表》(2010)进行汉字分类,对比中国官... 日本《常用汉字表》在2010年有了修改,因为颁布不久,所以至今日本《常用汉字表》和中国《现代汉语常用字表》的对比研究都是依据1981年颁布的《常用汉字表》中的1945个汉字。本文依据日本《常用汉字表》(2010)进行汉字分类,对比中国官方发行的《中日韩常用汉字对比分析》,用《常用汉字表》里的修改部分做了一个Excel字表,在字形上和读音上对日本常用汉字和中国现行汉字进行了对比。 展开更多
关键词 2010年《常用汉表》 日本汉 中国汉 形差异
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Normalized Design of Multi-channel LIF Digital Receiver
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作者 方航锋 郁发兴 汪海航 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第1期68-72,共5页
A design method for parallel processing application on multi-channel low-intermediate-frequency(LIF) digital receiver was presented. It is based on the DSP sub-array with a simple topology and operation timing to eval... A design method for parallel processing application on multi-channel low-intermediate-frequency(LIF) digital receiver was presented. It is based on the DSP sub-array with a simple topology and operation timing to evaluate and determine the processing capability and then construct the parallel processing array for multi-channel signals according to the restriction of operation timing. Using this method, the design of multi-channel digital receiver may be simplified. Finally, a design example was used to show how to apply this method. 展开更多
关键词 parallel processing digital receiver low intermediate frequency(LIF)
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New Changes of Mobile Banking Industry and Mobile Terminal-Bank Account Problem Solving Model in the Digital Era
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作者 Liu Jian 《International Journal of Technology Management》 2014年第7期5-8,共4页
In the digital era, the mobile-empowered customers have new power in the palms of their hands, which means that their shoppingand buying behaviors are being totally transformed by the ability to buy anything at any ti... In the digital era, the mobile-empowered customers have new power in the palms of their hands, which means that their shoppingand buying behaviors are being totally transformed by the ability to buy anything at any time from any place. Bank account is the base camp ofmoney in economic activity, therefore who wins the mobile terminal who embraces bank accounts, who embraces bank accounts who achievesthe world, for the winner can master customer resource and business foundation. This passage focuses on the issue that how to create bankaccounts on mobile terminal for mobile banking industry in the digital era, introduced the developing background of mobile banking industry,analyzed the main challenges mobile banking industry faces, and finally concluded a workable mobile terminal-bank account problem solvingmodel from strategy level, technical level and marketing level. 展开更多
关键词 Mobile Terminal Mobile Banking Industry Create Bank Accounts
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Forward Position Analysis of 5-DOF Parallel Mechanism 被引量:1
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作者 齐明 梅江平 《Transactions of Tianjin University》 EI CAS 2006年第6期434-437,共4页
A systematic method for the forward kinematics of a five degrees of freedom (5-DOF) parallel mechanism with the legs' topology 4-UPS/UPU, is developed. Such mechanism is composed of a movable platform connected to ... A systematic method for the forward kinematics of a five degrees of freedom (5-DOF) parallel mechanism with the legs' topology 4-UPS/UPU, is developed. Such mechanism is composed of a movable platform connected to the base by four identical 6-DOF active limbs plus one active limb with its DOF being exactly the same as the specified DQF of the movable platform. Three translational and two rotational DOFs can be achieved. Firstly, a set of polynomial equations of forward position analysis is formulated based on the architecture of the mechanism. Then the system of equations is degraded from five-dimensional to three-dimensional by means of analytic elimination. Method of least squares and Gauss-Newton algorithm are used to construct the objective function and to solve it, respectively. Example shows that through 4-time iteration within 16 ms the ohjective, function converaes to the provided error tolerance. 10^-4. 展开更多
关键词 parallel machines forward kinematics 5-DOF numerical analysis
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China's Electricity Industry at the Crossroads: New Challenges for Developing the Right Model of Regulation
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作者 Anastassios Gentzoglanis 《Chinese Business Review》 2012年第1期75-91,共17页
China is facing important challenges stemming from increasing rates of urbanization and aging population. To pursue its "harmonious society" objective without disrupting its path to development major overhauls are n... China is facing important challenges stemming from increasing rates of urbanization and aging population. To pursue its "harmonious society" objective without disrupting its path to development major overhauls are necessary in education, health, social security and above all in public services, particularly in electricity. China's electricity industry is at the crossroads. To meet the challenges, new models of regulation should be developed and applied. This paper examines the current state of the Chinese electricity industry and the burden it imposes on its public finances. It also reviews and critically examines the existing FIT (Europe) and RPS (USA) models of regulation and of promotion of renewable energies and advances on whether they are advantageous for China. It is argued that the electricity industry has already undergone important reforms but cross subsidies still exist, equivalent to 1.5% of China's GDP. Drastic rate rebalancing policies will create sustainability problems and a deterioration of China's public finances. To avoid such negative results, China has to further reform its electricity industry gradually and use wisely FIT-type programs to bring renewables into the grid and fulfill the Kyoto Protocol 展开更多
关键词 alternative models of regulation China's public finances cross subsidies FIT and RPS programs regulation of electricity industry renewable energy
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AN ADAPTIVELY TRAINED KERNEL-BASED NONLINEAR REPRESENTOR FOR HANDWRITTEN DIGIT CLASSIFICATION 被引量:12
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作者 Liu Benyong Zhang Jing 《Journal of Electronics(China)》 2006年第3期379-383,共5页
In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recentl... In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recently presented nonlinear classifier for optimal pattern representation, so that its generalization ability may be evaluated in time-variant situation and a sparser representation is obtained for computationally intensive tasks. The addressed techniques are applied to handwritten digit classification to illustrate the feasibility for pattern recognition. 展开更多
关键词 Pattern recognition Handwritten digit recognition Incremental learning Sparse representation Kernel-based Nonlinear Representor (KNR)
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Analysis of the Mechanical Behavior of Bovine Hoof Horn Using Digital Image Correlation
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作者 ZHANG Dong-sheng AROLA Dwayne LUO miao 《Chinese Journal of Biomedical Engineering(English Edition)》 2006年第3期103-112,共10页
In this study Digital Image Correlation (DIC) was adopted to evaluate the mechanical properties of bovine hoof horn. Using specific process, tensile specimens comprised of Zones 4 and 5 of the sole were excised from t... In this study Digital Image Correlation (DIC) was adopted to evaluate the mechanical properties of bovine hoof horn. Using specific process, tensile specimens comprised of Zones 4 and 5 of the sole were excised from the claws of the front and rear hooves of a mature Black Angus cow. After extraction the specimens were conditioned to obtain horn with relative moisture content of either 0% (dry) or 100% (wet) and then subjected to uniaxial tension to failure. The average elastic modulus (E) of all "dry" and "wet" hoof horn was 2870 ± 460 MPa and 102 ± 34 MPa respectively. Similarly, the average proportional limit stress (σ) was 29.0 ± 4.8 MPa and 1.4 ± 0.3 MPa respectively. Although the mechanical properties were dependent on distance from the dermal-epidermal junction, the influence of moisture on mechanical behavior was far greater. 展开更多
关键词 Digital image correlation Bovine hoof STIFFNESS STRENGTH
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Characteristics of Digital Broadcasting Technology and Its Development Research
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作者 Mo YANG 《International Journal of Technology Management》 2014年第11期7-9,共3页
Driven by the rapid development of agricultural science and technology, many techniques have been developed rapidly, especially the development of broadcasting technology which earth-shaking changes have taken place. ... Driven by the rapid development of agricultural science and technology, many techniques have been developed rapidly, especially the development of broadcasting technology which earth-shaking changes have taken place. The advent of digital broadcasting technology makes the broadcast technology enter a new stage. With its low energy consumption and large coverage area, digital broadcasting technology was widely welcomed by the broadcast television industry. This paper analyzes digital audio broadcasting, multimedia digital broadcasting and digital AM broadcasting, and further concretely elaborates the application prospects of digital broadcasting technology. 展开更多
关键词 shock digital broadcasting TECHNOLOGY CHARACTERISTICS APPLICATION
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Acquisition of Directional Parameters in Aerial Images Based on DEM Data
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作者 LIPingxiang YUJie BIANFuling 《Geo-Spatial Information Science》 2005年第1期23-27,共5页
This paper develops a method which can be used to assist aerial navigation by determining the spatial position and posture of the aerial photographic plane. After the method, aerial images match known DEM to capture t... This paper develops a method which can be used to assist aerial navigation by determining the spatial position and posture of the aerial photographic plane. After the method, aerial images match known DEM to capture the spatial position and posture. Some aerial images and terrain data are used to testify our method. Compared with those of analytic and stereo mappers, the results by our method are correspondent to real measurements well. 展开更多
关键词 aerial navigation aerial images DEM data
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Study on V_P/ V_S Variation Behavior in the Shanxi Region by the Wadati Single Station and Multi-earthquake Method
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作者 Weng Zhaoqiang Liang Xiangjun +2 位作者 Wu Haoyu Liu Linfei Li Li 《Earthquake Research in China》 CSCD 2015年第4期514-526,共13页
Based on arrival time data of seismic phases of ML≥2. 0 earthquakes measured at Shanxi Digital Seismic Network for the period from January 2001 to October 2014,V_P/ V_S in the Shanxi region is calculated using the Wa... Based on arrival time data of seismic phases of ML≥2. 0 earthquakes measured at Shanxi Digital Seismic Network for the period from January 2001 to October 2014,V_P/ V_S in the Shanxi region is calculated using the Wadati single station and multi-earthquake method,and an investigation is conducted into the variation behavior of V_P/ V_S in the Shanxi region before and after the three earthquakes of MS≥4. 5 in 2010. Our study finds that abnormal V_P/ V_S appeared earlier at distant stations before all of the three earthquakes,which is at the time range from 6 months to 1 year before the earthquakes,and later at near stations,at the time range 10 days to 2 months before earthquakes. Therefore,it s possible to narrow down the scope of the location in earthquake prediction from the distant and near station data. The calculations of Dongshan seismic station indicate that the size of the residual of the origin time has impact on the detail of V_P/ V_S variation,thus,appropriate thresholds should firstly be set for the residuals of origin time at each seismic station in practical application,to ensure scientific and steady V_P/ V_S calculations. 展开更多
关键词 Wadati single station and multi-earthquake method VP/ VS Shanxi region
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