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A Semi-Quantitative Analysis of Essential Micronutrient in Folium Lycii Using Laser-Induced Breakdown Spectroscopy Technique 被引量:3
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作者 孙对兄 苏茂根 +2 位作者 董晨钟 张大成 马新文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第4期478-481,共4页
Abstract In this paper, the capabilities of laser-induced breakdown spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Bas... Abstract In this paper, the capabilities of laser-induced breakdown spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Based on homogeneous plasma assumption, nine of essential micronutrients in folium lycii are identified. Using Saha equation and Boltzmann plot method electron density and plasma temperature are obtained, and their relative concentration (Ca, Mg, A1, Si, Ti, Na, K, Li, and Sr) are obtained employing a semi-quantitative method. 展开更多
关键词 PLASMA LIBS folium lycii semi-quantitative analysis
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Subspace Semi-supervised Fisher Discriminant Analysis 被引量:5
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作者 YANG Wu-Yi LIANG Wei +1 位作者 XIN Le ZHANG Shu-Wu 《自动化学报》 EI CSCD 北大核心 2009年第12期1513-1519,共7页
关键词 费希尔判别分析法 鉴别分析 离散度 降维方法
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LOCAL CORRELATION DISCRIMINANT ANALYSIS AND ITS SEMI-SUPERVISED EXTENSION 被引量:1
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作者 Chen Caikou Shi Jun 《Journal of Electronics(China)》 2011年第3期289-296,共8页
Considering limitations of Linear Discriminant Analysis (LDA) and Marginal Fisher Analysis (MFA), a novel discriminant analysis called Local Correlation Discriminant Analysis (LCDA) is proposed in this paper. The main... Considering limitations of Linear Discriminant Analysis (LDA) and Marginal Fisher Analysis (MFA), a novel discriminant analysis called Local Correlation Discriminant Analysis (LCDA) is proposed in this paper. The main idea behind LCDA is to use more robust similarity measure, correlation metric, to measure the local similarity between image data. This results in better classifi-cation performance. In addition, to further improve the discriminant power of LCDA, we extend LCDA to semi-supervised case, which can make use of both labeled and unlabeled data to perform dis-criminant analysis. Extensive experimental results on ORL and AR face databases demonstrate that the proposed LCDA and its semi-supervised version are superior to Principal Component Analysis (PCA), LDA, CEA, and MFA. 展开更多
关键词 semi-supervised learning Correlation metric Discriminant analysis Face recognition
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Structural Stress Monitoring and FEM Analysis of the Cutting Operation of the Main Bracket of A Semi-Submersible Platform 被引量:1
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作者 KOU Yu-feng YANG Jian-min +3 位作者 XU Sheng-wen PENG Tao LIU Jun WU Zhuo-wei 《China Ocean Engineering》 SCIE EI CSCD 2019年第6期649-659,共11页
For a semi-submersible platform in repair, the eight old main brackets which connect columns with pontoons need to be replaced by new ones. In order to ensure the safety of the cutting operation of the old main bracke... For a semi-submersible platform in repair, the eight old main brackets which connect columns with pontoons need to be replaced by new ones. In order to ensure the safety of the cutting operation of the old main bracket and calculate the initial stress condition of new main bracket, the structural stress monitoring of eight key spots is carried out, and then the calibrated finite element model is established according to the field monitoring results. Before cutting the main bracket and all associated structures, eight rectangular rosettes were installed, and a tailored cutting scheme was proposed to release the initial stress, in which the main bracket and associated column and pontoon plates were partly cut. During the cutting procedure, the strains of the monitoring spots were measured, and then the structural stress of the monitored spots were obtained. The stress variation characteristics at different spots during the initial cutting operation were shown and the initial stress condition of the monitored spots was figured out. The loading and support conditions of the semi-submersible platform were calibrated based on the measured initial stress condition, which made the finite element model more credible. The stress condition with the main bracket and associated structures being entirely cut out is analyzed by the Finite Element Method (FEM), which demonstrates the cutting operation to be safe and feasible. In addition, the calibrated finite element model can be used to calculate the initial stress condition of the new main bracket, which will be very helpful for the long-term stress monitoring on the main bracket. 展开更多
关键词 semi-submersible platform main bracket cutting operation field stress monitoring FEM analysis
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Can semi-quantitative evaluation of uncertain (type II) time-intensity curves improve diagnosis in breast DCE-MRI? 被引量:1
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作者 Roberta Fusco Salvatore Filice +9 位作者 Vincenza Granata Ylenia Mandato Annamaria Porto Massimiliano D’Aiuto Massimo Rinaldo Maurizio Di Bonito Mario Sansone Carlo Sansone Antonio Rotondo Antonella Petrillo Petrillo 《Journal of Biomedical Science and Engineering》 2013年第3期418-425,共8页
Objective/Background: Qualitative assessment of uncertain (type II) time-intensity curves (TICs) in breast DCE-MRI is problematic and operator dependent. The aim of this work is to evaluate if a semi-quantitative asse... Objective/Background: Qualitative assessment of uncertain (type II) time-intensity curves (TICs) in breast DCE-MRI is problematic and operator dependent. The aim of this work is to evaluate if a semi-quantitative assessment of uncertain TICs could improve overall diagnostic performance. Methods: In this study 49 lesions from 44 patients were retrospectively analysed. Per each lesion one region-of-interest (ROI)- averaged TIC was qualitatively evaluated by two radiologists in consensus: all the ROIs resulted in type II (uncertain) TIC. The same TICs were semi-quantitatively re-classified on the basis of the difference between the signal intensities of the last-time-point and of the peak: this difference was classified according to two different cut-off ranges (±5% and ±3%). All patients were cytological or histological biopsy proven. Fisher test and McNemar test were performed to evaluate if results were statistically significant (p < 0.05). Results: Using ±5% cut-off 16 TICs were reclassified as type III and 12 as type I while 21 were reclassified again as type II. Using ±3% 22 TICs were reclassified as type III and 16 as type I while 11 were reclassified again as type II. The semi-quantitative classification was compared to the histological-cytological results: the sensitivity, specificity, positive and negative predictive values obtained with ±3% were 77%, 91%, 91% and 78% respectively while using ±5% were 58%, 96%, 94% and 68% respectively. Using the ±5% cut-off 26/28 (93%) TICs were correctly reclassified while using the ±3% cut-off 34/38 (90%) TICs were correctly reclassified (p < 0.05). Conclusions: Semi-quantitative methods in kinetic curve assessment on DCE-MRI could improve classification of qualitatively uncertain TICs, leading to a more accurate classification of suspicious breast lesions. 展开更多
关键词 BREAST Cancer Dynamic CONTRAST Enhanced-MRI Time Intensity CURVE TRACER Kinetics semi-quantitative analysis
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Semi-supervised learning based probabilistic latent semantic analysis for automatic image annotation 被引量:1
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作者 Tian Dongping 《High Technology Letters》 EI CAS 2017年第4期367-374,共8页
In recent years,multimedia annotation problem has been attracting significant research attention in multimedia and computer vision areas,especially for automatic image annotation,whose purpose is to provide an efficie... In recent years,multimedia annotation problem has been attracting significant research attention in multimedia and computer vision areas,especially for automatic image annotation,whose purpose is to provide an efficient and effective searching environment for users to query their images more easily. In this paper,a semi-supervised learning based probabilistic latent semantic analysis( PLSA) model for automatic image annotation is presenred. Since it's often hard to obtain or create labeled images in large quantities while unlabeled ones are easier to collect,a transductive support vector machine( TSVM) is exploited to enhance the quality of the training image data. Then,different image features with different magnitudes will result in different performance for automatic image annotation. To this end,a Gaussian normalization method is utilized to normalize different features extracted from effective image regions segmented by the normalized cuts algorithm so as to reserve the intrinsic content of images as complete as possible. Finally,a PLSA model with asymmetric modalities is constructed based on the expectation maximization( EM) algorithm to predict a candidate set of annotations with confidence scores. Extensive experiments on the general-purpose Corel5k dataset demonstrate that the proposed model can significantly improve performance of traditional PLSA for the task of automatic image annotation. 展开更多
关键词 automatic image annotation semi-supervised learning probabilistic latent semantic analysis(PLSA) transductive support vector machine(TSVM) image segmentation image retrieval
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FINITE LAYER ANALYSIS FOR SEMI-INFINITE SOILS (Ⅱ)——SPECIAL CASES AND NUMERICAL EXAMPLES
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作者 卢文达 杨正文 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第11期987-993,共7页
In the present paper reductions of the finite layer mathod once studied in detail by the authors for the elastodvnamics of transverse isotropic bodies are given to several special cases. Two-dimensional problems, axis... In the present paper reductions of the finite layer mathod once studied in detail by the authors for the elastodvnamics of transverse isotropic bodies are given to several special cases. Two-dimensional problems, axisymmetric problems and static problems are discussed, respectively, and this finite layer method is also generalized to the problems in which materials possess viscous properties. Two numerical examples have been presented for the axisymmetric case. From these two examples it can be concluded that the finite layer method can be used to analyse semi-infinite layered soils and to deal with the problem of the interaction between soils and structures. 展开更多
关键词 semi-infinite soils finite layer method numerical analysis
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Modal Correlation Based Analysis on Dynamic Characters of a Commercial Semi-Trailer's Chassis Frames
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作者 冯慧华 左正兴 +1 位作者 廖日东 龙凯 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期140-145,共6页
In order to evaluate two different schemes' structural dynamic characters, dynamic response analysis of a commercial truck's main chassis frames is carried out. On the basis of correlation study between the tested a... In order to evaluate two different schemes' structural dynamic characters, dynamic response analysis of a commercial truck's main chassis frames is carried out. On the basis of correlation study between the tested and calculated modal results, the assembled frames' finite element analysis (FEA) models with sufficient precision are built up. Random response analysis in frequency domain is carried out with these FEA models, RMS values of yon Mises and main principle stresses of these two frames are obtained. It shows that the analysis resuits of the distributing tendency and concrete value ranges are coincident very well with test results. And from the results, it could be concluded that frames of scheme A endures relative better loading conditions and should be adopted as the final scheme. 展开更多
关键词 semi-TRAILER chassis frame random response modal correlation finite element analysis
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SEMI-ANALYTICAL AND SEMI-NUMERICAL METHOD FOR DYNAMIC ANALYSIS OF FOUNDATION
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作者 龚文惠 谢洪阳 王元汉 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第5期607-615,共9页
A semi-analytical and semi-numerical method is proposed for the dynamic analysis of foundations. The Lamb's solution and the approximate formulae were used to establish the relation of the contact force and deflectio... A semi-analytical and semi-numerical method is proposed for the dynamic analysis of foundations. The Lamb's solution and the approximate formulae were used to establish the relation of the contact force and deflection between the foundation and soil. Therefore, the foundation can be separated from soil and analyzed by FEM as for the static cases. The plate can be treated as that the known forces are acting on the upper surface, and the contact pressure from soil can be represented as the deflection. So that only the plate needs to be divided into elements in the analysis. By this method, a series of vibration problems, including various shapes and rigidities of foundations, different excitation frequencies, were analyzed. Furthermore, it can be used for the embedded foundation. The numerical examples show that this method has simplicity, highly accurate and versatile. It is an effective method for the dynamic analysis of foundations. 展开更多
关键词 dynamic analysis of foundation foundation plate FREQUENCY semi-analytical method finite element method
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Consideration of transient heat conduction in a semi-infinite medium using homotopy analysis method
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作者 A. Rezania A. Ghorbali +1 位作者 G. Domairry H. Bararnia 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第12期1625-1632,共8页
In the current work, transient heat conduction in a semi-infinite medium is considered for its many applications in various heat fields. Here, the homotopy analysis method (HAM) is applied to solve this problem and ... In the current work, transient heat conduction in a semi-infinite medium is considered for its many applications in various heat fields. Here, the homotopy analysis method (HAM) is applied to solve this problem and analytical results are compared with those of the exact and integral methods results. The results show that the HAM can give much better approximations than the other approximate methods: Changes in heat fluxes and profiles of temperature are obtained at different times and positions for copper, iron and aluminum. 展开更多
关键词 homotopy analysis method semi-infinite medium conduction transient heat transfer integral methods temperature profile
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Error Analysis and Its Offset on the NC Lathe Machine in Cutting a Semi-Sphere Surface
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作者 ZHENG Yu-cai LI Cheng-zhi LIU Chang-rong LIU Tao GUO Xiu-hua 《International Journal of Plant Engineering and Management》 2007年第4期221-226,共6页
This paper analyzed the errors that occurred by leaving the shape of the cutting edge out of consideration on a NC lathe machine in cutting a semi-sphere surface and brought forward a method to offset these errors and... This paper analyzed the errors that occurred by leaving the shape of the cutting edge out of consideration on a NC lathe machine in cutting a semi-sphere surface and brought forward a method to offset these errors and the correct calculated formula for some parameters on the basis of experiments. It has increased the manufacturing accuracy of the semi-sphere surface on the NC lathe machine. 展开更多
关键词 NC lathe machine semi-sphere error analysis
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A LAYERED NUMERICAL MODEL FOR SIMULATING THE GENERATION AND PROPAGATION OF INTERNAL TIDES OVER CONTINENTAL SLOPE II STABILITY ANALYSIS 被引量:1
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作者 杜涛 方国洪 方欣华 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第3期252-257,共6页
The stability, accuracy, and dispersion of a semi implicit finite difference scheme for the numerical solution of external mode were carefully analyzed in this study. The stability analysis was implemented with the vo... The stability, accuracy, and dispersion of a semi implicit finite difference scheme for the numerical solution of external mode were carefully analyzed in this study. The stability analysis was implemented with the von Neumann method and proved that the scheme is unconditionally stable. Study of their accuracy showed that the finite difference equations were consistent with the differential equations with second order accuracy. The Eulerian Lagrangian discretization of the convective terms was also discussed. The existence of dispersion was proved to be unfavorable for the achievement of the real solution. 展开更多
关键词 stability analysis external mode semi IMPLICIT finite DIFFERENCE scheme
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An Emotion Analysis Method Using Multi-Channel Convolution Neural Network in Social Networks 被引量:2
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作者 Xinxin Lu Hong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期281-297,共17页
As an interdisciplinary comprehensive subject involving multidisciplinary knowledge,emotional analysis has become a hot topic in psychology,health medicine and computer science.It has a high comprehensive and practica... As an interdisciplinary comprehensive subject involving multidisciplinary knowledge,emotional analysis has become a hot topic in psychology,health medicine and computer science.It has a high comprehensive and practical application value.Emotion research based on the social network is a relatively new topic in the field of psychology and medical health research.The text emotion analysis of college students also has an important research significance for the emotional state of students at a certain time or a certain period,so as to understand their normal state,abnormal state and the reason of state change from the information they wrote.In view of the fact that convolutional neural network cannot make full use of the unique emotional information in sentences,and the need to label a large number of highquality training sets for emotional analysis to improve the accuracy of the model,an emotional analysismodel using the emotional dictionary andmultichannel convolutional neural network is proposed in this paper.Firstly,the input matrix of emotion dictionary is constructed according to the emotion information,and the different feature information of sentences is combined to form different network input channels,so that the model can learn the emotion information of input sentences from various feature representations in the training process.Then,the loss function is reconstructed to realize the semi supervised learning of the network.Finally,experiments are carried on COAE 2014 and self-built data sets.The proposed model can not only extract more semantic information in emotional text,but also learn the hidden emotional information in emotional text.The experimental results show that the proposed emotion analysis model can achieve a better classification performance.Compared with the best benchmark model gram-CNN,the F1 value can be increased by 0.026 in the self-built data set,and it can be increased by 0.032 in the COAE 2014 data set. 展开更多
关键词 Emotion analysis model emotion dictionary convolution neural network semi supervised learning deep learning pooling feature feature mapping
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Isolation, Identification and Tissue Expression Profile Analysis of One Novel Differentially Expressed Sequence Tag in the Longissimus dorsi Muscle from Meishan, Meishan × Large White Hybrid and Large White Pigs 被引量:2
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作者 LIUYong-gang XIONGYuan-zhu DENGChang-yan 《Agricultural Sciences in China》 CAS CSCD 2004年第11期856-861,共6页
In order to detect the molecular mechanism of heterosis in pigs, the mRNA differential display technique was performed to investigate the differences of gene expression in the Longissimus dorsi tissue from Meishan, ... In order to detect the molecular mechanism of heterosis in pigs, the mRNA differential display technique was performed to investigate the differences of gene expression in the Longissimus dorsi tissue from Meishan, Meishan × Large White hybrid and Large White pigs with nine 3'-end anchored primers in combination with ten 5'-end arbitrary primers and nearly 3000 reproducible bands were examined. One novel expressed sequence tag (EST4, GenBank accession number: AY553914) that was differentially expressed in Meishan, Meishan× Large White hybrid and Large White pigs was isolated from the Longissimus dorsi muscle tissue and identified through semi-quantitative RT-PCR. BLAST analysis revealed that the 350 bp long EST (EST4) was not homologous to any of the known porcine genes. Tissue expression profile analyses showed that the EST4 was expressed in most of tissues.LIU Yong-gang, Ph D candidate 展开更多
关键词 mRNA differential display semi-quantitative RT-PCR Tissue expression profile analysis
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Probabilistic Approach to Risk Analysis of Chemical Spills at Sea
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作者 Magda Bogalecka Krzysztof Kolowrocki 《International Journal of Automation and computing》 EI 2006年第2期117-124,共8页
Risk analysis of chemical spills at sea and their consequences for sea environment are discussed. Mutual interactions between the process of the sea accident initiating events, the process of the sea environment threa... Risk analysis of chemical spills at sea and their consequences for sea environment are discussed. Mutual interactions between the process of the sea accident initiating events, the process of the sea environment threats, and the process of the sea environment degradation are investigated. To describe these three particular processes, the separate semi-Markov models are built. Furthermore, these models are jointed into one general model of these processes interactions. Moreover, some comments on the method for statistical identification of the considered models are proposed. 展开更多
关键词 Risk analysis dangerous chemicals sea accidents semi-Markov processes.
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3D analysis of functionally graded material plates with complex shapes and various holes
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作者 曹志远 唐寿高 程国华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第1期13-18,共6页
In this paper, the basic formulae for the semi-analytical graded FEM on FGM members are derived. Since FGM parameters vary along three space coordinates, the parameters can be integrated in mechanical equations. There... In this paper, the basic formulae for the semi-analytical graded FEM on FGM members are derived. Since FGM parameters vary along three space coordinates, the parameters can be integrated in mechanical equations. Therefore with the parameters of a given FGM plate, problems of FGM plate under various conditions can be solved. The approach uses 1D discretization to obtain 3D solutions, which is proven to be an effective numerical method for the mechanical analyses of FGM structures. Examples of FGM plates with complex shapes and various holes are presented. 展开更多
关键词 functionally graded material semi-analytical method complex shape 3D analysis HOLE
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Cloning,Expression and Bioinformatic Analysis of Dorsal Gene in Delia antique
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作者 Huimin WEI Yujuan ZHANG +1 位作者 Bin CHEN Shuang REN 《Plant Diseases and Pests》 CAS 2012年第2期28-32,共5页
[ Objective ] The aim was to explore the relationship between the Dorsal and diapause development of Delia araiqua. [ Method ] The full-length cDNA of Dorsal in D. antiqua was cloned through RACE. The similarity among... [ Objective ] The aim was to explore the relationship between the Dorsal and diapause development of Delia araiqua. [ Method ] The full-length cDNA of Dorsal in D. antiqua was cloned through RACE. The similarity among deduced amino acid sequence of Dorsal cDNA and the Dorsals of other 14 insect species were compared, and the phylogenetic analysis of these Dorsals was conducted. The expression level of Dorsal gene in winter-, summer- and non-diapausing pupae was analyzed. [ Result] The full-length of Dorsal cDNA sequence, 2 412 bp, was obtained with ORF 1974 bp, which coded 657 amino acids with predicted Mw 72.9 kDa and PI 8.5. The result of similarity comparison indicated that the DaDorsal was most related to those of Drosophlia melanogaster and Drosophlia pseudoobscura. The result of semi-quantitative RT-PCR analysis showed the expression level of Dorsal gene increased in characteristic duration of winter-, summer- and non- diapansing pupae, especially at the late diapanse, which might imply its relationship to D. antiqua diapause and development. [ Conclusion] The study lays the foundation for further study on gene function of Dorsal in insect diapause and development. 展开更多
关键词 DORSAL Delia ant/qua RACE Sequence analysis Phylogenetic analysis semi-quantitative RT-PCR
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Performance analysis of ultra-wideband based wireless sensor networks in indoor office LOS environment
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作者 吴宣利 罗超 +2 位作者 杨孝宗 孙陆宽 曹阳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第5期101-106,共6页
By analyzing the indoor office LOS channel model defined by IEEE 802.15.4a standard and deducing the variance for intra-symbol interference (IASI), inter-symbol interference (ISI) and multiuser interference (MUI), per... By analyzing the indoor office LOS channel model defined by IEEE 802.15.4a standard and deducing the variance for intra-symbol interference (IASI), inter-symbol interference (ISI) and multiuser interference (MUI), performance analysis model for ultra-wideband (UWB) based wireless sensor networks (WSN) is proposed, and the bit error rate (BER) formulation is also obtained. The comparison of performance analysis model with and without intra-symbol interference shows that the intra-symbol interference cannot be neglected and such interference will significantly decrease the system performance. In order to verify the proposed performance analysis model and BER formulation, the semi-definite programming (SDP) algorithm is used to obtain the pulses complying with the spectrum requirement of China and IEEE 802.15.4a standard, and by using such pulses, simulations and theoretical analysis are compared, the comparison results show the validity of the proposed performance analysis model and BER formulation. 展开更多
关键词 ULTRA-WIDEBAND IEEE 802.15.4a BER performance analysis semi-definite programming
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Kernel Dimensionality Reduction Evaluation on Various Dimensions of Effective Subspaces for Cancer Patient Survival Analysis
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作者 Ito Wasito Yoon Chin Soon S.Z. Mohd Hashim 《通讯和计算机(中英文版)》 2011年第8期619-623,共5页
关键词 生存分析 子空间 癌症病人 内核 尺寸 DNA微阵列 基因分类 评价
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EVOLUTION FILTRATION PROBLEMS WITH SEAWATER INTRUSION: TWO-PHASE FLOW DUAL MIXED VARIATIONAL ANALYSIS 被引量:1
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作者 Gonzalo ALDUNCIN 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1142-1162,共21页
Tow-phase flow mixed variational formulations of evolution filtration problems with seawater intrusion are analyzed. A dual mixed fractional flow velocity-pressure model is considered with an air-fresh water and a fre... Tow-phase flow mixed variational formulations of evolution filtration problems with seawater intrusion are analyzed. A dual mixed fractional flow velocity-pressure model is considered with an air-fresh water and a fresh water-seawater characterization. For analysis and computational purposes, spatial decompositions based on nonoverlapping multidomains, above and below the sea level, are variationally introduced with internal boundary fluxes dualized as weak transmission constraints. Further, parallel augmented and exactly penalized duality algorithms, and proximation semi-implicit time marching schemes, are established and analyzed. 展开更多
关键词 two-phase flow in coastal aquifers fractional two-phase flow dual mixed variational analysis macro-hybrid variational formulations augmented exactly penalized duality algorithms proximation semi-implicit time marching schemes
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