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制取固定式腭弓精确工作模的方法
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作者 梁华 陈巧玲 沈璇 《实用口腔医学杂志》 CAS CSCD 北大核心 2006年第4期498-498,共1页
关键词 固定式 腭弓 上颌第一磨牙 固定矫治器 取模方法 临床
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计算机汉字库开发液晶汉字显示数据的方法 被引量:5
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作者 田会方 张洪昌 《武汉理工大学学报(信息与管理工程版)》 CAS 2005年第4期83-86,共4页
控制技术的发展要求在仪器设备中越来越需要利用液晶来显示各种控制参数,针对这一目的,论述了汉字的编码规则,以及如何利用计算机中的汉字库,制作针对不同液晶控制器的汉字显示数据库。
关键词 汉字库 显示数据 取模方法 液晶控制器
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印模材衬垫法修复全口义齿69例分析
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作者 冯静 王绍升 《中国社区医师(医学专业)》 2003年第6期23-23,共1页
关键词 全口义齿修复 材衬垫法 取模方法 效果
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计算机汉字库研究及其在液晶显示系统上的应用
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作者 宋亚岚 孙巍 张洪昌 《教育技术导刊》 2008年第3期83-84,共2页
论述了汉字的编码规则,以及如何利用计算机中的汉字库,制作针对不同液晶控制器的汉字显示数据库。
关键词 汉字库 显示数据 取模方法 液晶控制器
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Modified method for extraction of watershed boundary with digital elevation modeling 被引量:5
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作者 王殿中 郝占庆 熊在平 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期283-286,共4页
Boundary extraction of watershed is an important step in forest landscape research. The boundary of the upriver wa-tershed of the Hunhe River in the sub-alpine Qingyuan County of eastern Liaoning Province, China was e... Boundary extraction of watershed is an important step in forest landscape research. The boundary of the upriver wa-tershed of the Hunhe River in the sub-alpine Qingyuan County of eastern Liaoning Province, China was extracted by digital elevation modeling (DEM) data in ArcInfo8.1. Remote sensing image of the corresponding region was applied to help modify its copy according to Enhanced Thematic Mapper (ETM) image抯 profuse geomorphological structure information. Both the DEM-dependent boundary and modified copy were overlapped with county map and drainage network map to visually check the effects of result. Overlap of county map suggested a nice extraction of the boundary line since the two layers matched precisely, which indicated the DEM-dependent boundary by program was effective and precise. Further upload of drainage network showed discrepancies between the boundary and the drainage network. Altogether, there were three sections of the extraction result that needed to correct. Compared with this extraction boundary, the modified boundary had a better match to the drainage network as well as to the county map. Comprehensive analysis demonstrated that the program extraction has generally fine precision in position and excels the digitized result by hand. The errors of the DEM-dependant extraction are due to the fact that it is difficult for program to recognize sections of complex landform especially altered by human activities, but these errors are discernable and adjustable because the spatial resolution of ETM image is less than that of DEM. This study result proved that application of remote sensing information could help obtain better result when DEM method is used in extraction of watershed boundary. 展开更多
关键词 Forested watershed Boundary extraction Digital elevation modeling (DEM) Enhanced thematic mapper (ETM)
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Snake Model for the Extraction of Loess Shoulder-line from DEMs 被引量:6
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作者 YAN Shi-jiang TANG Guo'an +1 位作者 LI Fa-yuan ZHANG Lei 《Journal of Mountain Science》 SCIE CSCD 2014年第6期1552-1559,共8页
Shoulder lines are the most important landform demarcations for geographical analysis,soil erosion modeling and land use planning in the Loess Plateau area of China.This paper proposes an automatic,effective and accur... Shoulder lines are the most important landform demarcations for geographical analysis,soil erosion modeling and land use planning in the Loess Plateau area of China.This paper proposes an automatic,effective and accurate method of determining loess shoulder line from DEMs by integrating a hydrological D8 algorithm and a snake model.The watershed boundary line is adopted as the initial contour which evolves to identify the exact position of loess shoulder-line by the guidance of an external force of snake model from DEMs.Experiments show that the method overcomes the difficulties in both threshold selection for edge detection and the disconnecting issues in former extraction approaches.The accuracy evaluation of shoulder-line maps from the two test sites of the loess plateau area show obvious improvements in the extraction.The average contour matching distance of the new method is 12.0 m on 5 m resolution DEM,and shows improvement in the accuracy and continuity.The comparisons of accuracy evaluations of the two test sites show that the snake model method performs better in the loess plain area than in the area with high gully density. 展开更多
关键词 Snake model DEM loess shoulder-line
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Extraction and Analysis of Gully Head of Loess Plateau in China Based on Digital Elevation Model 被引量:17
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作者 ZHU Hongchun TANG Guoan +1 位作者 QIAN Kejian LIU Haiying 《Chinese Geographical Science》 SCIE CSCD 2014年第3期328-338,共11页
In China′s Loess Plateau area, gully head is the most active zone of a drainage system in gully areas. The differentiation of loess gully head follows geospatial patterns and reflects the process of the loess landfor... In China′s Loess Plateau area, gully head is the most active zone of a drainage system in gully areas. The differentiation of loess gully head follows geospatial patterns and reflects the process of the loess landform development and evolution of its drainage system to some extent. In this study, the geomorphic meaning, basic characteristics, morphological structure and the basic types of loess gully heads were systematically analysed. Then, the loess gully head′s conceptual model was established, and an extraction method based on Digital Elevation Model(DEM) for loess gully head features and elements was proposed. Through analysing the achieved statistics of loess gully head features, loess gully heads have apparently similar and different characteristics depending on the different loess landforms where they are found. The loess head characteristics reflect their growth period and evolution tendency to a certain degree, and they indirectly represent evolutionary mechanisms. In addition, the loess gully developmental stages and the evolutionary processes can be deduced by using loess gully head characteristics. This study is of great significance for development and improvement of the theoretical system for describing loess gully landforms. 展开更多
关键词 Loess Plateau loess gully head Digital Elevation Model (DEM) loess landform evolution feature extraction STATISTICALANALYSIS
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Field analysis of metallogenic information and its application 被引量:3
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作者 毛先成 胡超 +3 位作者 周尚国 张宝一 汪凡云 曾文波 《Journal of Central South University》 SCIE EI CAS 2011年第1期196-207,共12页
Focusing on the issue to deal with inadequate extraction of metallogenic information especially geological information,a new method of extracting metallogenic information based on field model,i.e.the field analysis me... Focusing on the issue to deal with inadequate extraction of metallogenic information especially geological information,a new method of extracting metallogenic information based on field model,i.e.the field analysis method of metallogenic information,was proposed.In addition,a case study by using the method of the extraction of metallogenic information from the west Guangxi and southeast Yunnan district as an example was performed.The representation method for the field models of metallogenic information,including the metallogenic influence field model and the metallogenic distance field model,was discussed by introducing the concept of the field theory,based on the characteristic analysis of the distance gradualness and the influence superposition of metallogenic information.According to the field theory superposition principle and the spatial distance analysis method,the mathematical models for the metallogenic influence field and the metallogenic distance field of point,line and area geological bodies were derived out by using parameter equation and calculus.Based on the metallogenic background analysis,the metallogenic information field models of synsedimentary faults and manganese sedimentary basins were built.The relationship between the metallogenic information fields and the manganese mineralization distribution was also investigated by using the method of metallogenic information field analysis.The instance study indicates that the proposed method of metallogenic information field analysis is valid and useful for extracting the ore-controlling information of synsedimentary faults and manganese sedimentary basins in the study area,with which the extraction results are significant both statistically and geologically. 展开更多
关键词 metallogenic information field model metallogenic prognosis manganese ore
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A simple method to extract glacier length based on Digital Elevation Model and glacier boundaries for simple basin type glacier 被引量:3
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作者 JI Qin YANG Tai-bao +3 位作者 HE Yi QIN Yan DONG Jun HU Fan-sheng 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1776-1790,共15页
Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit freque... Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit frequent temporal change. In this paper, we describe a new Arc GIS-based method that can derive glacier flow lines for determining glacier length based on digital elevation model and glacier outlines. This method involves(1) extraction of the highest and lowest points on a glacier,(2) calculation of 10-m contour lines on the glacier from 10 m to 100 m height, and(3) connection of the midpoints of each contour line with the highest and the lowest points in order to create a flow line, which is subsequently smoothed. In order to assess the reliability of this method, we tested the algorithm's results against flow lines calculated using field measurements, analysing data from the Chinese Glacier Inventory, and manual interpretation. These data showed that the new automated method is effective in deriving glacier flow lines when contour lines are relatively large; in particular, when they are between 70 m and 100 m. Nonetheless, a key limitation of the algorithm is the requirement to automatically delete repeated and closed curves in the pre-treatment processes. In addition to calculating glacier flow lines for derivation of glacier length, this method also can be used to effectively determine glacier terminus change. 展开更多
关键词 Glacier length Flow lines Glacier boundary DEM Arc GIS
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A robust feature extraction approach based on an auditory model for classification of speech and expressiveness 被引量:5
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作者 孙颖 V.Werner 张雪英 《Journal of Central South University》 SCIE EI CAS 2012年第2期504-510,共7页
Based on an auditory model, the zero-crossings with maximal Teager energy operator (ZCMT) feature extraction approach was described, and then applied to speech and emotion recognition. Three kinds of experiments were ... Based on an auditory model, the zero-crossings with maximal Teager energy operator (ZCMT) feature extraction approach was described, and then applied to speech and emotion recognition. Three kinds of experiments were carried out. The first kind consists of isolated word recognition experiments in neutral (non-emotional) speech. The results show that the ZCMT approach effectively improves the recognition accuracy by 3.47% in average compared with the Teager energy operator (TEO). Thus, ZCMT feature can be considered as a noise-robust feature for speech recognition. The second kind consists of mono-lingual emotion recognition experiments by using the Taiyuan University of Technology (TYUT) and the Berlin databases. As the average recognition rate of ZCMT approach is 82.19%, the results indicate that the ZCMT features can characterize speech emotions in an effective way. The third kind consists of cross-lingual experiments with three languages. As the accuracy of ZCMT approach only reduced by 1.45%, the results indicate that the ZCMT features can characterize emotions in a language independent way. 展开更多
关键词 speech recognition emotion recognition zero-crossings Teager energy operator speech database
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Analysis of characteristic functions for equivalent circuit model in monolithic transformer 被引量:1
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作者 吴忠洁 Lu Jingxue +1 位作者 Huang Fengyi Jiang Nan 《High Technology Letters》 EI CAS 2012年第2期124-127,共4页
A model of monolithic transformers is presented, which is analyzed with characteristic functions. A closed- form analytical approach to extract all the model parameters for the equivalent circuit of Si-based on-chip t... A model of monolithic transformers is presented, which is analyzed with characteristic functions. A closed- form analytical approach to extract all the model parameters for the equivalent circuit of Si-based on-chip transformers is proposed. A novel de-coupling technique is first developed to reduce the complexity in the Y parameters for the transformer, and the model parameters can then be extracted analytically by a set of characteristic functions. Simulation based on the extracted parameters has been carried out for transformers with different structures, and good accuracy is obtained compared to a 3-demensional full-wave numerical electro- magnetic field solver. The presented approach will be very useful to provide a scalable and wide-band compact circuit model for Si-based RF transformers. 展开更多
关键词 TRANSFORMER parameter extraction compact model radio frequency integrate circuit((RFIC)
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Vibration-based feature extraction of determining dynamic characteristic for engine block low vibration design 被引量:2
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作者 杜宪峰 李志军 +3 位作者 毕凤荣 张俊红 王霞 邵康 《Journal of Central South University》 SCIE EI CAS 2012年第8期2238-2246,共9页
In order to maintain vibration performances within the limits of the design, a vibration-based feature extraction method for dynamic characteristic using empirical mode decomposition (EMD) and wavelet analysis was p... In order to maintain vibration performances within the limits of the design, a vibration-based feature extraction method for dynamic characteristic using empirical mode decomposition (EMD) and wavelet analysis was proposed. The proposed method was verified experimentally and numerically by implementing the scheme on engine block. In the implementation process, the following steps were identified to be important: 1) EMD technique in order to solve the feature extraction of vibration signals; 2) Vibration measurement for the purpose of confirming the structural weak regions of engine block in experiment; 3) Finite element modeling for the purpose of determining dynamic characteristic in time region and frequency region to affirm the comparability of response character corresponding to improvement schemes; 4) Adopting a feature index oflMF for structural improvement based on EMD and wavelet analysis. The obtained results show that IMF of signal is more sensitive to response character corresponding to improvement schemes. Finally, examination of the results confirms that the proposed vibration-based feature extraction method is very robust, and focuses on the relative merits of modification and full-scale structural optimization of engine, together with the creation of new low-vibration designs. 展开更多
关键词 feature extraction dynamic characteristic finite element model empirical mode decomposition diesel engine block
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Research on the Automatic Pattem Abstraction and Recognition Methodology for Large-scale Database System based on Natural Language Processing 被引量:1
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作者 RongWang Cuizhen Jiao Wenhua Dai 《International Journal of Technology Management》 2015年第9期125-127,共3页
In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connec... In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connection between nodes, data across different nodes and even regional distribution are well recognized. In order to reduce data redundancy and model design of the database will usually contain a lot of forms we combine the NLP theory to optimize the traditional method. The experimental analysis and simulation proves the correctness of our method. 展开更多
关键词 Pattern Abstraction and Recognition Database System Natural Language Processing.
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A Parametric Autoregressive Model for the Extraction of Electric Network Frequency Fluctuations in Audio Forensic Authentication
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作者 Tarek E. Gemayel Martin Bouchard 《Journal of Energy and Power Engineering》 2016年第8期504-512,共9页
This paper proposes a new method for extracting ENF (electric network frequency) fluctuations from digital audio recordings for the purpose of forensic authentication. It is shown that the extraction of ENF componen... This paper proposes a new method for extracting ENF (electric network frequency) fluctuations from digital audio recordings for the purpose of forensic authentication. It is shown that the extraction of ENF components from audio recordings is realizable by applying a parametric approach based on an AR (autoregressive) model. The proposed method is compared to the existing STFT (short-time Fourier transform) based ENF extraction method. Experimental results from recorded electrical grid signals and recorded audio signals show that the proposed approach can improve the time resolution in the extracted ENF fluctuations and improve the detection of tampering with short alterations in longer audio recordings. 展开更多
关键词 Audio forensic authentication electric network frequency fluctuations autoregressive modeling tampering anddiscontinuity detection.
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Intrinsic mode characteristic analysis and extraction in underwater cylindrical shell acoustic radiation 被引量:4
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作者 LIU QingYu FANG ShiLiang +3 位作者 CHENG Qiang CAO Jin AN Liang LUO XinWei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第7期1339-1345,共7页
Target dimension is important information in underwater target classification. An intrinsic mode characteristic extraction method in underwater cylindrical shell acoustic radiation was studied in this paper based on t... Target dimension is important information in underwater target classification. An intrinsic mode characteristic extraction method in underwater cylindrical shell acoustic radiation was studied in this paper based on the mechanism of shell vibration to gain the information about its dimension instead of accurate inversion processing. The underwater cylindrical shell vibration and acoustic radiation were first analyzed using mode decomposition to solve the wave equation. The characteristic of acoustic radiation was studied with different cylindrical shell lengths, radii, thickness, excitation points and fine structures. Simulation results show that the intrinsic mode in acoustic radiation spectrum correlates closely with the geometry dimensions of cylindrical shells. Through multifaceted analysis, the strongest intrinsic mode characteristic extracted from underwater shell acoustic radiated signal was most likely relevant to the radiated source radius. Then, partial information about unknown source dimension could be gained from intrinsic mode characteristic in passive sonar applications for underwater target classification. Experimental data processing results verified the effectiveness of the method in this paper. 展开更多
关键词 cylindrical shell mode decomposition acoustic radiation characteristic
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Application of Kinetic Models in Describing Soil Potassium Release Characteristics and Their Correlations with Potassium Extracted by Chemical Methods 被引量:8
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作者 A. R. HOSSEINPUR H. R. MOTAGHIAN 《Pedosphere》 SCIE CAS CSCD 2013年第4期482-492,共11页
Potassium (K) release characteristics in soil play a significant role in supplying available K. Information on K-release characteristics in soils of central Iran is limited. The objectives of this study were to dete... Potassium (K) release characteristics in soil play a significant role in supplying available K. Information on K-release characteristics in soils of central Iran is limited. The objectives of this study were to determine K release characteristics and correlations of K release rate constants with K extracted by different chemical methods in surface soils of ten calcareous soils of central Iran. The kinetics of K release in the soils was determined by successive extraction with 0.01 mol L-1 CaC12 in a period of 2-2017 h at 25±1℃. Soil K was extracted by distilled water, 0.5 mol L-1 MgNO3, 0.002 mol L-1 SrC12, 0.1 mol L-1 BaC12, 0.01 mol L-1 CaC12, 1 mol L-1 NaC1, 1 mol L-1 boiling HNO3, 1 mol L-1 NH4OAC, Mehlich 1, 0.002 mol L-1 SrC12 + 0.05 mol L-1 citric acid, and ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA). A plot of cumulative amounts of K released showed a discontinuity in slope at 168 h. Thus, two equations were applied to two segments of the total reaction time (2-168 and 168-2 017 h). Cumulative amounts of K released ranged from 55 to 299 mg kg-1 in 2-168 h and from 44 to 119 mg kg-1 in 168-2 017 h. Release kinetics of K in the two time segments conformed fairly well to parabolic diffusion, simplified Elovich, and power function models. There was a wide variation in the K release rate constants. Increasingly higher average concentrations of soil K were extracted by distilled water, Mehlich 1, SrC12, CaC12, SrC12 + citric acid, AB-DTPA, MgNO3, NaCI, NH4OAc, BaCI2, and HNO3. Potassium release rate constants were significantly correlated with K extracted. The results of this study showed that information obtained from mathematical modeling in two reaction time segments can help to estimate the K-supplying power of soils. 展开更多
关键词 chemical extraction calcareous soils mathematical modeling release rate constant time segments
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THE MODIFIED METHOD OF CHARACTERISTICS WITH FINITE ELEMENT OPERATOR-SPLITTING PROCEDURES FOR COMPRESSIBLE MULTICOMPONENT DISPLACEMENT PROBLEM 被引量:1
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作者 YUAN Yirang (Institute of Mathematics, Shandong University, Jinan 250100, China) 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2003年第1期30-45,共16页
For the three-dimensional compressible multicomponent displacement problem we put forward the modified method of characteristics with finite element operator-splitting procedures and make use of operator-splitting,cha... For the three-dimensional compressible multicomponent displacement problem we put forward the modified method of characteristics with finite element operator-splitting procedures and make use of operator-splitting,characteristic method,calculus of variations,energy method,negative norm estimate,two kinds of test functions and the theory of prior estimates and techniques.Optimal order estimates in L^2 norm are derived for the error in the approximate solution.These methods have been successfully used in oil-gas resources estimation,enhanced oil recovery simulation and seawater intrusion numerical simulation. 展开更多
关键词 Multicomponent displacement 3-dimensional compressibility OPERATOR-SPLITTING characteristics finite element optimal order L2 error estimates.
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