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多分次立体定向放射治疗在椎体转移肿瘤治疗中的作用及应用前景 被引量:2
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作者 杨昊 马林 《中国医学装备》 2016年第5期151-155,共5页
椎体转移肿瘤的立体定向放射治疗可以给予靶区适形的高剂量,同时形成陡峭的剂量梯度,有利于保护周围正常组织,特别是脊髓。与常规放射治疗相比较,立体定向放射治疗提高肿瘤局部控制率并有利于缓解症状,成为椎体转移瘤术后辅助治疗及根... 椎体转移肿瘤的立体定向放射治疗可以给予靶区适形的高剂量,同时形成陡峭的剂量梯度,有利于保护周围正常组织,特别是脊髓。与常规放射治疗相比较,立体定向放射治疗提高肿瘤局部控制率并有利于缓解症状,成为椎体转移瘤术后辅助治疗及根治性治疗新的治疗模式。尽管该技术在临床中应用越来越广泛,但目前仍没有优化的分割方案。文献评阅表明基于放射生物、物理以及临床方面的相关研究,多分次立体定向放射治疗在临床中具有一定的优势。 展开更多
关键词 椎体转移 立体定向放射治疗 多分次 分割方案
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HIERARCHIC GREY QUASI-PREFERRED ANALYSIS MODEL AND ITS APPLICATION
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作者 李炳军 刘思峰 任盈盈 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期78-83,共6页
The grey quasi-preferred analysis (GQPA) is one of important methods for realizing system analysis to conquer the limitations of the existing GQPA model, without any considerations to the difference of the different b... The grey quasi-preferred analysis (GQPA) is one of important methods for realizing system analysis to conquer the limitations of the existing GQPA model, without any considerations to the difference of the different behavioral factor′s importance. It could not be used to analyze the complex system with multi-hierarchy correlation factors, the weighted synthetic method for calculating abstract incidence degrees between the system beha-vioral characteristics and correlative factors in different hierarchies is given out,and the hierarchic grey quasi-preferred analysis (HGQPA) model is established. The effectiveness of the HGQPA model is tested by the scientific-technical system of Jiangsu Province. The depth and the range of the application of GQPA are developed, and the HGQPA model is regarded as a new approach to systemically analyze the complex systems with multi-hierarchy correlation factors. 展开更多
关键词 multi-hierarchy quasi-preferred analysis MODEL grey system
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APPLICATION OF IMPROVED EMD IN VIBRATION SIGNAL FEATURE EXTRACTION OF VEHICLE
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作者 辛江慧 安木金 +1 位作者 张雨 任成龙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期193-198,共6页
In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD ... In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD is applied to the feature extraction of vehicle vibration signals. First, the multi-autocorrelation method is adopted in each input signal,so the noise is reduced effectively. Then, EMD is used to deal with these signals,and the intrinsic mode functions (IMFs) are obtained. Finally, for obtaining the feature information of these signals, the Hilbert transformation and the spectrum analysis are performed in some IMFs. Theoretical analysis and ex- periment verify the effectiveness of the method, which are valuable reference for the same engineering problems. 展开更多
关键词 empirical mode decomposition (EMD) vehicle vibration signal multi-autocorrelation feature ex- traction
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Multiple attenuation using λ–f domain high-resolution Radon transform 被引量:5
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作者 李志娜 李振春 +1 位作者 王鹏 徐强 《Applied Geophysics》 SCIE CSCD 2013年第4期433-441,511,共10页
The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed the 2- fdomain high-resolution Radon transform based on t... The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed the 2- fdomain high-resolution Radon transform based on the fast and modified parabolic Radon transform presented by Abbad. The introduction of a new variable 2 makes the transform operator frequency-independent. Thus, we need to calculate the transform operator and its inverse operator only once, which greatly improves the computational efficiency. Besides, because the primaries and multiples are distributed on straight lines with different slopes in the 2-fdomain, we can easily choose the filtering operator to suppress the multiples. At the same time, the proposed method offers the advantage of high-resolution Radon transform, which can greatly improve the precision of attenuating the multiples. Numerical experiments suggest that the multiples are well suppressed and the amplitude versus offset characteristics of the primaries are well maintained. Real data processing results further verify the effectiveness and feasibility of the method. 展开更多
关键词 λ-f domain high resolution parabolic Radon transform multiple attenuation
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Analyses of Multiplicity and Stability Patterns of Agglomeration Controlled Precipitation with Both Primary and Secondary Nucleations 被引量:2
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作者 尹秋响 张美景 王静康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第2期202-207,共6页
The possibility of multiplicity in an isothermal continuous mixed suspension-mixed product removalcrystallizer is explored using the bifurcation theory. A process involving agglomeration controlled precipitationis con... The possibility of multiplicity in an isothermal continuous mixed suspension-mixed product removalcrystallizer is explored using the bifurcation theory. A process involving agglomeration controlled precipitationis considered in which secondary nucleation occurs simultaneously with primary nucleation. The determinantequations for the existence of multiple steady states are developed and the multiplicity boundaries dependent on thephysical and kinetic properties and operational parameters of the process are obtained by resolving these determinantequations. The number of steady states in the precipitator for various multiplicity regions is determined and thelinear stability of these steady states is analyzed by using the Routh criterion. 展开更多
关键词 PRECIPITATION mixed suspension-mixed product removal crystallizer AGGLOMERATION MULTIPLICITY sta- bility
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Study on Self-Affine Fractal and Multi-Fractal Features of Geomorphic System in the Tianshan Area of Xinjiang Region, China
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作者 Li Meng, Zhu Lingren and Long HaiyingSeismological Bureau of Xinjiang Uygur Autonomous Region, Urumqi 830011, China 《Earthquake Research in China》 2003年第3期256-264,共9页
In this paper, we use the standard deviation method and the fixed mass method to study the self affine fractal and multi fractal features along two topographic profiles across different tectonic geomorphic elements in... In this paper, we use the standard deviation method and the fixed mass method to study the self affine fractal and multi fractal features along two topographic profiles across different tectonic geomorphic elements in the Tianshan area of Xinjiang region, China. The results show that in the studied scaling range, the two profiles display different scaling fractal features, and the form and value range of multi fractal spectra D q also show different characteristics. The study suggests that the landforms are not completely random, but are deterministically random. The fractal dimension values in different scaling ranges express the mode, intensity and spatial dimension of the endogenic and exogenic processes. Meanwhile, a boundary point between the macroscopic and microscopic scales of geomorphic process is suggested to be about 5 km. These results are of significance in quantitative study of geomorphic dynamics. 展开更多
关键词 TIANSHAN GEOMORPHOLOGY Self affine fractal Multiple fractal Dynamics
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Multilevel Pattern Mining Architecture for Automatic Network Monitoring in Heterogeneous Wireless Communication Networks 被引量:8
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作者 Zhiguo Qu John Keeney +2 位作者 Sebastian Robitzsch Faisal Zaman Xiaojun Wang 《China Communications》 SCIE CSCD 2016年第7期108-116,共9页
The rapid development of network technology and its evolution toward heterogeneous networks has increased the demand to support automatic monitoring and the management of heterogeneous wireless communication networks.... The rapid development of network technology and its evolution toward heterogeneous networks has increased the demand to support automatic monitoring and the management of heterogeneous wireless communication networks.This paper presents a multilevel pattern mining architecture to support automatic network management by discovering interesting patterns from telecom network monitoring data.This architecture leverages and combines existing frequent itemset discovery over data streams,association rule deduction,frequent sequential pattern mining,and frequent temporal pattern mining techniques while also making use of distributed processing platforms to achieve high-volume throughput. 展开更多
关键词 automatic network monitoring sequential pattern mining episode discovery module
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A Multi-Level Authorization Based Tenant Separation Mechanism in Cloud Computing Environment
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作者 Wei Ma Zhen Han +1 位作者 Xiaoyong Li Jiqiang Liu 《China Communications》 SCIE CSCD 2016年第5期162-171,共10页
Separation issue is one of the most important problems about cloud computing security. Tenants should be separated from each other based on cloud infrastructure and different users from one tenant should be separated ... Separation issue is one of the most important problems about cloud computing security. Tenants should be separated from each other based on cloud infrastructure and different users from one tenant should be separated from each other with the constraint of security policies. Learning from the notion of trusted cloud computing and trustworthiness in cloud, in this paper, a multi-level authorization separation model is formally described, and a series of rules are proposed to summarize the separation property of this model. The correctness of the rules is proved. Furthermore, based on this model, a tenant separation mechanism is deployed in a real world mixed-critical information system. Performance benchmarks have shown the availability and efficiency of this mechanism. 展开更多
关键词 separation cloud computing multi-level authorization model security model
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Analytic Expression of Arbitrary Matrix Elements for Boson Exponential Quadratic Polynomial Operators
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作者 XU Xiu-Wei REN Ting-Qi LIU Shu-Yan MA Qiu-Ming LIU Sheng-Dian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期41-44,共4页
Making use of the transformation relation among usual, normal, and antinormal ordering for the multimode boson exponential quadratic polynomial operators (BEQPO's)I we present the analytic expression of arbitrary m... Making use of the transformation relation among usual, normal, and antinormal ordering for the multimode boson exponential quadratic polynomial operators (BEQPO's)I we present the analytic expression of arbitrary matrix elements for BEQPO's. As a preliminary application, we obtain the exact expressions of partition function about the boson quadratic polynomial system, matrix elements in particle-number, coordinate, and momentum representation, and P representation for the BEQPO's. 展开更多
关键词 Boson exponential quadratic polynomial operator matrix element P representation partition function of Boson quadratic polynomial system
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Alunite processing method selection using the AHP and TOPSIS approaches under fuzzy environment 被引量:3
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作者 Alizadeh Shahab Salari Rad Mohammad Mehdi Bazzazi Abbas Aghajani 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1017-1023,共7页
Alunite is the most important non bauxite resource for alumina. Various methods have been proposed and patented for processing alunite, but none has been performed at industrial scale and no technical,operational and ... Alunite is the most important non bauxite resource for alumina. Various methods have been proposed and patented for processing alunite, but none has been performed at industrial scale and no technical,operational and economic data is available to evaluate methods. In addition, selecting the right approach for alunite beneficiation, requires introducing a wide range of criteria and careful analysis of alternatives.In this research, after studying the existing processes, 13 methods were considered and evaluated by 14 technical, economic and environmental analyzing criteria. Due to multiplicity of processing methods and attributes, in this paper, Multi Attribute Decision Making methods were employed to examine the appropriateness of choices. The Delphi Analytical Hierarchy Process(DAHP) was used for weighting selection criteria and Fuzzy TOPSIS approach was used to determine the most profitable candidates. Among 13 studied methods, Spanish, Svoronos and Hazan methods were respectively recognized to be the best choices. 展开更多
关键词 Alunite Mineral processing methods Multi Attribute Decision Making Delphi Analytical Hierarchy Process (DAHP)Fuzzy TOPSIS
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Use of Multi-criteria Decision Analysis Methods for Water Supply Problems: A Framework for Improved Rainwater Harvesting
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作者 Omolara Lade David Oloke Ezekiel Chinyio Michael Fullen 《Journal of Environmental Science and Engineering(A)》 2012年第7期909-917,共9页
Several conflicting objectives are considered in decision-making. MCDA (multi-criteria decision analysis) methods are developed to facilitate better decision making by decision-makers. Water supply problems are comp... Several conflicting objectives are considered in decision-making. MCDA (multi-criteria decision analysis) methods are developed to facilitate better decision making by decision-makers. Water supply problems are complex problems with multiple decision making and criteria. Hence, the use of multi-criteria decision analysis is very appropriate for solving these problems. Multi-criteria decision analysis can be divided into three main groups: value measurement models, goals, aspiration and reference level models and outranking models. The methods listed have been applied to water supply problems, especially in the evaluation of alternative water supply strategies. Each method has its advantages and limitations. A good alternative for concluding a better-suited method for water supply problems is to apply more than one method, either in combination to make use of the strengths of both methods, or in parallel to obtain a broader decision basis for the decision maker. Previous studies of MCDA in water supply planning have usually considered water supply networks with only one water service delivery. Advanced water supply sources with multiple water service delivery systems have been neglected. This is an on-going study in which analytical hierarchical multi-criteria decision analysis methods are proposed for solving water supply problems and a framework for improved rainwater harvesting systems will be developed. 展开更多
关键词 Water supply multiple-criteria decision analysis sustainability.
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A method for choice of optimum scale on land use monitoring in Tarim River Basin
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作者 赵金 陈曦 +2 位作者 包安明 张超 史婉丽 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期340-350,共11页
Optimal scale is one of the important issues in ecology and geography.Based on land-use data of the Tarim River Basin in Xinjiang of China in the 1950s,regarding the area of land use types as the parameter in scale se... Optimal scale is one of the important issues in ecology and geography.Based on land-use data of the Tarim River Basin in Xinjiang of China in the 1950s,regarding the area of land use types as the parameter in scale selecting,the histograms of the patches in area are charted.Then,by reinforcing the normalized scale variances(NSV) with 3 landscape indi-ces,the scale characteristics of land use in the Tarim River Basin can be summarized.(1) NSV in the Tarim River up to a maximum at scale of 1:50,000 which is considered appropriate for the Tarim River.(2) Diversity indices of saline land are consistent with NSV's.Diversity indices and NSV of sandy land showed that the appropriate scale is in the same scale domain.There is a significant difference between diversity indices and NSV of forestland and shrub-land.(3) Fractal dimension of sandy land and saline land showed a hierarchical structure at a scale of 1:10,000.Fractal dimension of forestland and shrubland are distributed under the same hierarchical structure in the region. 展开更多
关键词 appropriate scale land use monitoring normalized scale variance landscape indices Tarim River Basin
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Ecological and Economic System Health Assessment Based on Fuzzy Set Pair Analysis:A Case Study of Northwest Region,China 被引量:1
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作者 Chen Junfei Zhou Xiaolan Wang Huimin 《Chinese Journal of Population,Resources and Environment》 2012年第3期107-115,共9页
Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more an... Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system. 展开更多
关键词 ecological and economic system (EES) health assess-ment fuzzy analytic hierarchy process (FAHP) set pair analysis(SPA) Pressure-State-Response (PSR)
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ON FUNCTIONAL DECOMPOSITION OF MULTIVARIATE POLYNOMIALS WITH DIFFERENTIATION AND HOMOGENIZATION
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作者 Shangwei ZHAO Ruyong FENG Xiao-Shan GAO 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第2期329-347,共19页
This paper gives a theoretical analysis for the algorithms to compute functional decomposition for multivariate polynomials based on differentiation and homogenization which were proposed by Ye, Dai, and Lam (1999) ... This paper gives a theoretical analysis for the algorithms to compute functional decomposition for multivariate polynomials based on differentiation and homogenization which were proposed by Ye, Dai, and Lam (1999) and were developed by Faugere, Perret (2006, 2008, 2009). The authors show that a degree proper functional decomposition for a set of randomly decomposable quartic homoge- nous polynomials can be computed using the algorithm with high probability. This solves a conjecture proposed by Ye, Dal, and Lam (1999). The authors also propose a conjecture which asserts that the decomposition for a set of polynomials can be computed from that of its homogenization and show that the conjecture is valid with high probability for quartic polynomials. Finally, the authors prove that the right decomposition factors for a set of polynomials can be computed from its right decomposition factor space. 展开更多
关键词 Cryptosystem analysis functional decomposition homogeneous polynomials multivariatepolynomial right factor space.
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Building Communication Capacity for Good Governance: A Multi-leveled Analysis
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作者 Zhang Li 《Fudan Journal of the Humanities and Social Sciences》 2011年第1期108-123,共16页
This paper stresses the role of media and communication in promoting good governance by presenting a multi-leveled analytical approach to issues and cases both nationally and internationally. The study draws policy im... This paper stresses the role of media and communication in promoting good governance by presenting a multi-leveled analytical approach to issues and cases both nationally and internationally. The study draws policy implications for the Chinese government as regards to integrating building communication capacity into governance agenda. Even though there is a growing attention on implementing communication programs into policies, the study on the role of the media and communication in governance has not been dearly conceptualized. This 15aper analyses the role of media and communication in promoting good governance from the levels of state governments, civil society and the general public, respectively. It argues that strong communication capacity at the governmental level increases governance effectiveness through helping to build consensus in policy-making and promote development policies; strong communication capacity of the civil society expands the development results when the NGOs work together with the mass media to promote their activities and prioritize development goals through media's agenda-setting and framing functions; and strong communication capacity strengthens the voice of the public and empower them to hold the government account through the media's watch-dog role. The paper concludes that improving communication capacity is essential to achieve good governance for the Chinese government. 展开更多
关键词 good governance media and communication governance effectiveness civil society public empowerment
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Multiple weighted estimates for commutators of multilinear fractional integral operators 被引量:2
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作者 CHEN SongQing WU HuoXiong 《Science China Mathematics》 SCIE 2013年第9期1879-1894,共16页
Multilinear commutators and iterated commutators of multilinear fractional integral operators with BMO functions are studied. Both strong type and weak type endpoint weighted estimates involving the multiple weights f... Multilinear commutators and iterated commutators of multilinear fractional integral operators with BMO functions are studied. Both strong type and weak type endpoint weighted estimates involving the multiple weights for such operators are established and the weak type endpoint results are sharp in some senses. In particular, we extend the results given by Cruz-Uribe and Fiorenza in 2003 and 2007 to the multilinear setting. Moreover, we modify the weak type of endpoint weighted estimates and improve the strong type of weighted norm inequalities on the multilinear commutators given by Chen and Xue in 2010 and 2011. 展开更多
关键词 multilinear fractional integrals COMMUTATORS maximal operators multiple weights A P q weighted norm inequalities
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OPTIMAL HIERARCHY STRUCTURES FOR MULTI-ATTRIBUTE-CRITERIA DECISIONS 被引量:2
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作者 Stan LIPOVETSKY 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第2期228-242,共15页
A problem of a hierarchy structure optimization is considered.Hierarchical structures arewidely used in the Analytic Hierarchy Process,conjoint analysis,and various other methods of multiplecriteria decision making.Th... A problem of a hierarchy structure optimization is considered.Hierarchical structures arewidely used in the Analytic Hierarchy Process,conjoint analysis,and various other methods of multiplecriteria decision making.The problem consists in finding a structure that needs a minimum number ofpair comparisons for a given total number of the alternatives.For an optimal hierarchy,the minimumefforts are needed for eliciting data and synthesizing the local preferences across the hierarchy to getthe global priorities or utilities.Special estimation techniques are developed and numerical simulationsperformed.Analytical and numerical results suggest optimal ways of priority evaluations for practicalmanagerial decisions in a complex environment. 展开更多
关键词 Analytic Hierarchy Process conjoint analysis hierarchy optimization pair comparisons.
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A multi-class large margin classifier
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作者 Liang TANG Qi XUAN +2 位作者 Rong XIONG Tie-jun WU Jian CHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第2期253-262,共10页
Currently there are two approaches for a multi-class support vector classifier(SVC). One is to construct and combine several binary classifiers while the other is to directly consider all classes of data in one optimi... Currently there are two approaches for a multi-class support vector classifier(SVC). One is to construct and combine several binary classifiers while the other is to directly consider all classes of data in one optimization formulation. For a K-class problem(K>2),the first approach has to construct at least K classifiers,and the second approach has to solve a much larger op-timization problem proportional to K by the algorithms developed so far. In this paper,following the second approach,we present a novel multi-class large margin classifier(MLMC). This new machine can solve K-class problems in one optimization formula-tion without increasing the size of the quadratic programming(QP) problem proportional to K. This property allows us to construct just one classifier with as few variables in the QP problem as possible to classify multi-class data,and we can gain the advantage of speed from it especially when K is large. Our experiments indicate that MLMC almost works as well as(sometimes better than) many other multi-class SVCs for some benchmark data classification problems,and obtains a reasonable performance in face recognition application on the AR face database. 展开更多
关键词 MULTI-CLASSIFICATION Support vector machine (SVM) Quadratic programming (QP) problem Large margin
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The dynatomic periodic curves for polynomial z→z^d+c are smooth and irreducible
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作者 GAO Yan OU YaFei 《Science China Mathematics》 SCIE 2014年第6期1175-1192,共18页
We prove here the smoothness and the irreducibility of the periodic dynatomic curves(c,z)∈C2such that z is n-periodic for zd+c,where d 2.We use the method provided by Buff and Lei where they proved the conclusion for... We prove here the smoothness and the irreducibility of the periodic dynatomic curves(c,z)∈C2such that z is n-periodic for zd+c,where d 2.We use the method provided by Buff and Lei where they proved the conclusion for d=2.The proof for smoothness is based on elementary calculations on the pushforwards of specific quadratic differentials,following Thurston and Epstein,while the proof for irreducibility is a simplified version of Lau-Schleicher’s proof by using elementary arithmetic properties of kneading sequence instead of internal addresses. 展开更多
关键词 dynatomic curve IRREDUCIBLE Multibrot set
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Integral closure of a quartic extension
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作者 TAN ShengLi XIE DaJun 《Science China Mathematics》 SCIE CSCD 2015年第3期553-564,共12页
Let R be a Noetherian unique factorization domain such that 2 and 3 are units,and let A=R[α]be a quartic extension over R by adding a rootαof an irreducible quartic polynomial p(z)=z4+az2+bz+c over R.We will compute... Let R be a Noetherian unique factorization domain such that 2 and 3 are units,and let A=R[α]be a quartic extension over R by adding a rootαof an irreducible quartic polynomial p(z)=z4+az2+bz+c over R.We will compute explicitly the integral closure of A in its fraction field,which is based on a proper factorization of the coefficients and the algebraic invariants of p(z).In fact,we get the factorization by resolving the singularities of a plane curve defined by z4+a(x)z2+b(x)z+c(x)=0.The integral closure is expressed as a syzygy module and the syzygy equations are given explicitly.We compute also the ramifications of the integral closure over R. 展开更多
关键词 algebraic invariants quartic extension integral closure DISCRIMINANT SYZYGY
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