Dissimilarity learning for nominal data

Defining a good distance (dissimilarity) measure between patterns is of crucial importance in many classification and clustering algorithms. While a lot of work has been performed on continuous attributes, nominal attributes are more difficult to handle. A popular approach is to use the value difference metric (VDM) to define a real-valued distance measure on nominal values. However, VDM treats the attributes separately and ignores any possible interactions among attributes. In this paper, we propose the use of adaptive dissimilarity matrices for measuring the dissimilarities between nominal values. These matrices are learned via optimizing an error function on the training samples. Experimental results show that this approach leads to better classification performance. Moreover, it also allows easier interpretation of (dis)similarity between different nominal values.     

Discretization and fitting of nominal data for autonomous robots

This paper presents methodologies to discretize nominal robot paths extracted from 3-D CAD drawings. Behind robot path discretization is the ability to have a robot adjusting the traversed paths so that the contact between robot tool and work-piece is properly maintained. In addition, a hybrid force/motion control system based on Fuzzy-PI control is proposed to adjust robot paths with external sensory feedback. All these capabilities allow to facilitate the robot programming process and to increase the robot’s autonomy.     

A measure of variance for hierarchical nominal attributes

The need for measuring the dispersion of nominal categorical attributes appears in several applications, like clustering or data anonymization. For a nominal attribute whose categories can be hierarchically classified, a measure of the variance of a sample drawn from that attribute is proposed which takes the attribute’s hierarchy into account. The new measure is the reciprocal of “consanguinity”: the less related the nominal categories in the sample, the higher the measured variance. For non-hierarchical nominal attributes, the proposed measure yields results consistent with previous diversity indicators. Applications of the new nominal variance measure to economic diversity measurement and data anonymization are also discussed.     

A hierarchical semantic-based distance for nominal histogram comparison

We propose a new distance called Hierarchical Semantic-Based Distance (HSBD), devoted to the comparison of nominal histograms equipped with a dissimilarity matrix providing the semantic correlations between the bins. The computation of this distance is based on a hierarchical strategy, progressively merging the considered instances (and their bins) according to their semantic proximity. For each level of this hierarchy, a standard bin-to-bin distance is computed between the corresponding pair of histograms. In order to obtain the proposed distance, these bin-to-bin distances are then fused by taking into account the semantic coherency of their associated level. From this modus operandi, the proposed distance can handle histograms which are generally compared thanks to cross-bin distances. It preserves the advantages of such cross-bin distances (namely robustness to histogram translation and histogram bin size issues), while inheriting the low computational cost of bin-to-bin distances. Validations in the context of geographical data classification emphasize the relevance and usefulness of the proposed distance.     

结合半监督与主动学习的复杂名词短语识别

为克服传统的全监督机器学习模型的训练依赖于大量的标注样本的弱点,给出一种半监督学习和主动学习相结合的算法。根据主动学习选择策略选择最有价值的句子来标注,结合半监督来充分利用未标注的句子。结合汉语语料的特点,改进主动学习选择策略。实验结果表明,与采用随机选择标注样本相比,在使用相同数目的训练样本的情况下,该算法可以使学习器的F-score调高10.2%,在分类器到达相同性能的情况下,人工标注量可以减少32%,学习器对标注样本的需求得到了有效降低。     

ARCADE: A prediction method for nominal variables

The main problem considered in this paper consists of binarizing categorical (nominal) attributes having a very large number of values (20⁴ in our application). A small number of relevant binary attributes are gathered from each initial attribute. Let us suppose that we want to binarize a categorical attribute v with L values, where L is large or very large. The total number of binary attributes that can be extracted from v is 2^L−1− 1, which in the case of a large L is prohibitive. Our idea is to select only those binary attributes that are predictive; and these shall constitute a small fraction of all possible binary attributes. In order to do this, the significant idea consists in grouping the L values of a categorical attribute by means of an hierarchical clustering method. To do so, we need to define a similarity between values, which is associated with their predictive power. By clustering the L values into a small number of clusters (J), we define a new categorical attribute with only J values. The hierarchical clustering method used by us, AVL, allows to choose a significant value for J. Now, we could consider using all the 2^L−1− 1 binary attributes associated with this new categorical attribute. Nevertheless, the J values are tree-structured, because we have used a hierarchical clustering method. We profit from this, and consider only about 2 × J binary attributes. If L is extremely large, for complexity and statistical reasons, we might not be able to apply a clustering algorithm directly. In this case, we start by “factorizing” v into a pair (v², v²), each one with about √L(v) values. For a simple example, consider an attribute v with only four values m₁,m₂, m₃,m₄. Obviously, in this example, there is no need to factorize the set of values of v, because it has a very small number of values. Nevertheless, for illustration purposes, v could be decomposed (factorized) into 2 attributes with only two values each; the correspondence between the values of v and (v², v²) would be     

7.

基于互信息的分类属性数据特征选择算法     

顾文强  李志华 《计算机工程与应用》2014,50(16):135-139

提出了一种针对分类属性数据特征选择的新算法。通过给出一种能够直接评价分类属性数据特征选择的评价函数新定义,重新构造能实现分类属性数据信息量、条件互信息、特征之间依赖度定义的计算公式,并在此基础上,提出了一种基于互信息较大相关、较小冗余的特征选择（MRLR）算法。MRLR算法在特征选择时不仅考虑了特征与类标签之间的相关性,而且还考虑了特征之间的冗余性。大量的仿真实验表明,MRLR算法在针对分类属性数据的特征选择时,能获得冗余度小且更具代表性的特征子集,具有较好的高效性和稳定性。     

8.

Online check and recovery techniques for dependable embeddedprocessors     

Pflanz  M. Vierhaus  H.T. 《Micro, IEEE》2001,21(5):24-40

Efficient online check and fast recovery techniques for embedded systems aim to detect single or multiple errors within the same clock cycle in which they occur. It is argued that such techniques can enable fast error correction; detection of illegal states, micro- rollback for transient and permanent faults; and prioritized, controlled recovery     

9.

AGREE,a package for computing nominal scale agreement     

Roel Popping 《Computational statistics & data analysis》1984,2(2):182-185

     

10.

Color set selection for nominal coding by Hopfield networks     

P. Campadelli  P. Mora  R. Schettini 《The Visual computer》1995,11(3):150-155

The specification of high contrast color sets is a fundamental step towards the optimal use of color to represent qualitative data. The problem is formulated here as a combinatorial optimization problem on graphs, and a Hopfield neural network of analog neurons is designed to find approximate solutions. The network's performance, heuristically evaluated, appears satisfactory. The simplicity, versatility, and robustness of the algorithm make it a valid tool in nominal color coding.     

11.

A unified framework for consistency check     

Bing Liu 《国际智能系统杂志》1995,10(8):691-713

Constraint Satisfaction Problem (CSP) involves finding values for variables to satisfy a set of constraints. Consistency check is the key technique in solving this class of problems. Past research has developed many algorithms for such a purpose, e.g., node consistency, are consistency, generalized node and arc consistency, specific methods for checking specific constraints, etc. In this article, an attempt is made to unify these algorithms into a common framework. This framework consists of two parts. the first part is a generic consistency check algorithm, which allows and encourages each individual constraint to be checked by its specific consistency methods. Such an approach provides a direct way of practical implementation of the CSP model for real problem-solving. the second part is a general schema for describing the handling of each type of constraint. the schema characterizes various issues of constraint handling in constraint satisfaction, and provides a common language for expressing, discussing, and exchanging constraint handling techniques. © 1995 John Wiley & Sons, Inc.     

12.

一种用于立体图像匹配的改进稀疏匹配算法     

陈佳坤  罗谦  曾玉林 《微机发展》2011,(10):63-65,69

立体匹配有着广泛的应用前景,是计算机视觉领域的研究热点。立体匹配是立体视觉中最为关键和困难的一步,它的目标是计算标识匹配像素位置的视差图。文中提出的立体匹配算法基于置信传播（Belief Propagation,BP）。左图像首先经过非均匀采样,得到一个内容自适应的网格近似表示。算法的关键是使用基于置信传播的立体匹配算法,匹配稀疏的左图像和右图像得到稀疏视差图。通过左图像得到网格,稀疏视差图可以经过简单的插值得到稠密视差图。实验结果表明,该方法与现有稀疏立体匹配技术相比在视差图质量上平均有40％的提高。     

13.

Robust MPC for tracking zone regions based on nominal predictions     

A. Ferramosca  D. Limon  A.H. González  I. Alvarado  E.F. Camacho 《Journal of Process Control》2012,22(10):1966-1974

This paper deals with the problem of robust tracking of target sets using a model predictive control (MPC) law. Real industries applications often require a control strategy in which some system outputs are controlled within specified ranges or zones (zone control), while some others variables – possibly including input variables – are steered to fixed target or setpoint. From a theoretical point of view, the control objective of this kind of problem can be seen as a target set (in the output space) instead of a target point, since inside the zones there are no preferences between one point or another. This problem is particularly interesting in case of additive disturbances which might push the outputs out of the zones. In this work, a stable robust MPC formulation for constrained linear systems, based on nominal predictions is presented. The main features of this controller are the use of nominal predictions, restricted constraints and the concept of distance from a point to a set as offset cost function. The controller ensures both recursive feasibility and local optimality. The properties of the controller are shown in a simulation test, in which we consider a subsystem of an industrial FCC system.     

14.

Scoring and selecting terms for text categorization   总被引：1，自引：0，他引：1  

Montanes  E. Diaz  I. Ranilla  J. Combarro  E.F. Fernandez  J. 《Intelligent Systems, IEEE》2005,20(3):40-47

We propose a set of (machine learning) ML-based scoring measures for conducting feature selection. We've tested these measures on documents from two well-known corpora, comparing them with other measures previously applied for this purpose. In particular, we've analyzed which measure obtains the best overall classification performance in terms of properties such as precision and recall, emphasizing to what extent some statistical properties of the corpus affects performance. The results show that some of our measures outperform the traditional measures in certain situations.     

15.

中文名词性谓词语义角色标注的特征研究   总被引：1，自引：0，他引：1  

徐靖  李军辉  朱巧明  李培峰 《计算机应用》2011,31(6):1671-1674

在语义角色标注中,相对于动词性谓词,名词性谓词与其角色之间的结构更灵活和复杂。为了更好地捕获这些结构化信息,通过对名词性谓词语义角色标注相关特征集的研究,探索了新的单词特征和句法特征,用于名词性谓词语义角色标注。基于正确句法树和正确谓词识别,中文名词性谓词语义角色标注的F1值达到了73.99,优于目前国内外的同类系统;基于自动句法树和自动谓词识别,性能F1值为57.16。最后,讨论了使用动词性谓词的特征实例来提高名词性谓词SRL的准确率,然而性能的提高并不是很明显。     

16.

Parametric synchronizations in mobile nominal calculi     

Roberto Bruni  Ivan Lanese   《Theoretical computer science》2008,402(2-3):102

We present and compare P-PRISMA and F-PRISMA, two parametric calculi that can be instantiated with different interaction policies, defined as synchronization algebras with mobility of names (SAMs). In particular, P-PRISMA is based on name transmission (P-SAM), like π-calculus, and thus exploits directional (input–output) communication only, while F-PRISMA is based on name fusion (F-SAM), like Fusion calculus, and thus exploits a more symmetric form of communication. However, P-PRISMA and F-PRISMA can easily accommodate many other high-level synchronization mechanisms than the basic ones available in π-calculus and Fusion, hence allowing for the development of a general meta-theory of mobile calculi. We define for both the labeled operational semantics and a form of strong bisimilarity, showing that the latter is compositional for any SAM. We also discuss reduction semantics and weak bisimilarity. We give several examples based on heterogeneous SAMs, we investigate the case studies of π-calculus and Fusion calculus giving correspondence theorems, and we show how P-PRISMA can be encoded in F-PRISMA. Finally, we show that basic categorical tools can help to relate and to compose SAMs and PRISMA processes in an elegant way.     

17.

Unsupervised learning with mixed numeric and nominal data   总被引：1，自引：0，他引：1  

Li  C. Biswas  G. 《Knowledge and Data Engineering, IEEE Transactions on》2002,14(4):673-690

Presents a similarity-based agglomerative clustering (SBAC) algorithm that works well for data with mixed numeric and nominal features. A similarity measure proposed by D.W. Goodall (1966) for biological taxonomy, that gives greater weight to uncommon feature value matches in similarity computations and makes no assumptions about the underlying distributions of the feature values, is adopted to define the similarity measure between pairs of objects. An agglomerative algorithm is employed to construct a dendrogram, and a simple distinctness heuristic is used to extract a partition of the data. The performance of the SBAC algorithm has been studied on real and artificially-generated data sets. The results demonstrate the effectiveness of this algorithm in unsupervised discovery tasks. Comparisons with other clustering schemes illustrate the superior performance of this approach     

18.

行为级模型功能比对验证的自动方法学     

廖璐  候春源  李跃平  王美  刘欢艳  黄丞权  徐南南  董丽霞 《电子技术应用》2019,45(8):63-67

在混合信号芯片设计领域,Verilog/Systemverilog/VHDL等行为级模型被广泛应用于描述模拟和混合信号模块的电路特性,用以帮助实现更快速全面的全芯片功能验证。为了保证正确、有效和全面的全芯片功能验证,电路模块的行为级模型和晶体管级设计之间的功能比对验证(Behavior vs.Schematic,BVS)非常关键。在此之前,利用现有的EDA工具,只能进行逻辑状态的BVS矢量检查,而不能进行实数类型的矢量检查。为了更好地描述模拟和混合信号模块的行为特性,采用了Wreal模型和SV-UDT(Systemverilog-User Defined Type),因此对EDA工具提出了新的要求,需要其支持实数类型的矢量检查。本文描述了一种行为级模型功能比对验证的自动方法学,基于Cadence XPS仿真器的矢量检查功能,可以同时实现逻辑状态和实数类型的自动比对检查。实数类型矢量检查是向EDA供应商Cadence提出的一种新的概念和需求,且已经在XPS仿真器中成功实现。     

19.

Capture-avoiding substitution as a nominal algebra     

Murdoch J. Gabbay  Aad Mathijssen 《Formal Aspects of Computing》2008,20(4-5):451-479

Substitution is fundamental to the theory of logic and computation. Is substitution something that we define on syntax on a case-by-case basis, or can we turn the idea of substitution into a mathematical object? We give axioms for substitution and prove them sound and complete with respect to a canonical model. As corollaries we obtain a useful conservativity result, and prove that equality-up-to-substitution is a decidable relation on terms. These results involve subtle use of techniques both from rewriting and algebra. A special feature of our method is the use of nominal techniques. These give us access to a stronger assertion language, which includes so-called ‘freshness’ or ‘capture-avoidance’ conditions. This means that the sense in which we axiomatise substitution (and prove soundness and completeness) is particularly strong, while remaining quite general.     

20.

On the existence of nominal plants     

AHMED K. EL-SAKKARY 《International journal of control》2013,86(5):2093-2095

In this paper we consider single-input single-output (SISO) linear time-invariant systems represented by their ‘meromorphic’ transfer functions, k(s). We assume that k(s) is representative of a given set of uncertainty containing k, and we would like to introduce conditions for determining if a nominal plant exists for k, which would then be used for both analysis and design. It is shown that uncertainty sets representing marginally stable (or unstable) dipoles do not possess nominal plants. Some concluding remarks and suggestions for future research are provided.     

基于互信息的分类属性数据特征选择算法

提出了一种针对分类属性数据特征选择的新算法。通过给出一种能够直接评价分类属性数据特征选择的评价函数新定义,重新构造能实现分类属性数据信息量、条件互信息、特征之间依赖度定义的计算公式,并在此基础上,提出了一种基于互信息较大相关、较小冗余的特征选择（MRLR）算法。MRLR算法在特征选择时不仅考虑了特征与类标签之间的相关性,而且还考虑了特征之间的冗余性。大量的仿真实验表明,MRLR算法在针对分类属性数据的特征选择时,能获得冗余度小且更具代表性的特征子集,具有较好的高效性和稳定性。     

Online check and recovery techniques for dependable embeddedprocessors

Efficient online check and fast recovery techniques for embedded systems aim to detect single or multiple errors within the same clock cycle in which they occur. It is argued that such techniques can enable fast error correction; detection of illegal states, micro- rollback for transient and permanent faults; and prioritized, controlled recovery     

Color set selection for nominal coding by Hopfield networks

The specification of high contrast color sets is a fundamental step towards the optimal use of color to represent qualitative data. The problem is formulated here as a combinatorial optimization problem on graphs, and a Hopfield neural network of analog neurons is designed to find approximate solutions. The network's performance, heuristically evaluated, appears satisfactory. The simplicity, versatility, and robustness of the algorithm make it a valid tool in nominal color coding.     

A unified framework for consistency check

Constraint Satisfaction Problem (CSP) involves finding values for variables to satisfy a set of constraints. Consistency check is the key technique in solving this class of problems. Past research has developed many algorithms for such a purpose, e.g., node consistency, are consistency, generalized node and arc consistency, specific methods for checking specific constraints, etc. In this article, an attempt is made to unify these algorithms into a common framework. This framework consists of two parts. the first part is a generic consistency check algorithm, which allows and encourages each individual constraint to be checked by its specific consistency methods. Such an approach provides a direct way of practical implementation of the CSP model for real problem-solving. the second part is a general schema for describing the handling of each type of constraint. the schema characterizes various issues of constraint handling in constraint satisfaction, and provides a common language for expressing, discussing, and exchanging constraint handling techniques. © 1995 John Wiley & Sons, Inc.     

一种用于立体图像匹配的改进稀疏匹配算法

立体匹配有着广泛的应用前景,是计算机视觉领域的研究热点。立体匹配是立体视觉中最为关键和困难的一步,它的目标是计算标识匹配像素位置的视差图。文中提出的立体匹配算法基于置信传播（Belief Propagation,BP）。左图像首先经过非均匀采样,得到一个内容自适应的网格近似表示。算法的关键是使用基于置信传播的立体匹配算法,匹配稀疏的左图像和右图像得到稀疏视差图。通过左图像得到网格,稀疏视差图可以经过简单的插值得到稠密视差图。实验结果表明,该方法与现有稀疏立体匹配技术相比在视差图质量上平均有40％的提高。     

Robust MPC for tracking zone regions based on nominal predictions

This paper deals with the problem of robust tracking of target sets using a model predictive control (MPC) law. Real industries applications often require a control strategy in which some system outputs are controlled within specified ranges or zones (zone control), while some others variables – possibly including input variables – are steered to fixed target or setpoint. From a theoretical point of view, the control objective of this kind of problem can be seen as a target set (in the output space) instead of a target point, since inside the zones there are no preferences between one point or another. This problem is particularly interesting in case of additive disturbances which might push the outputs out of the zones. In this work, a stable robust MPC formulation for constrained linear systems, based on nominal predictions is presented. The main features of this controller are the use of nominal predictions, restricted constraints and the concept of distance from a point to a set as offset cost function. The controller ensures both recursive feasibility and local optimality. The properties of the controller are shown in a simulation test, in which we consider a subsystem of an industrial FCC system.     

Scoring and selecting terms for text categorization

We propose a set of (machine learning) ML-based scoring measures for conducting feature selection. We've tested these measures on documents from two well-known corpora, comparing them with other measures previously applied for this purpose. In particular, we've analyzed which measure obtains the best overall classification performance in terms of properties such as precision and recall, emphasizing to what extent some statistical properties of the corpus affects performance. The results show that some of our measures outperform the traditional measures in certain situations.     

中文名词性谓词语义角色标注的特征研究

在语义角色标注中,相对于动词性谓词,名词性谓词与其角色之间的结构更灵活和复杂。为了更好地捕获这些结构化信息,通过对名词性谓词语义角色标注相关特征集的研究,探索了新的单词特征和句法特征,用于名词性谓词语义角色标注。基于正确句法树和正确谓词识别,中文名词性谓词语义角色标注的F1值达到了73.99,优于目前国内外的同类系统;基于自动句法树和自动谓词识别,性能F1值为57.16。最后,讨论了使用动词性谓词的特征实例来提高名词性谓词SRL的准确率,然而性能的提高并不是很明显。     

Parametric synchronizations in mobile nominal calculi

We present and compare P-PRISMA and F-PRISMA, two parametric calculi that can be instantiated with different interaction policies, defined as synchronization algebras with mobility of names (SAMs). In particular, P-PRISMA is based on name transmission (P-SAM), like π-calculus, and thus exploits directional (input–output) communication only, while F-PRISMA is based on name fusion (F-SAM), like Fusion calculus, and thus exploits a more symmetric form of communication. However, P-PRISMA and F-PRISMA can easily accommodate many other high-level synchronization mechanisms than the basic ones available in π-calculus and Fusion, hence allowing for the development of a general meta-theory of mobile calculi. We define for both the labeled operational semantics and a form of strong bisimilarity, showing that the latter is compositional for any SAM. We also discuss reduction semantics and weak bisimilarity. We give several examples based on heterogeneous SAMs, we investigate the case studies of π-calculus and Fusion calculus giving correspondence theorems, and we show how P-PRISMA can be encoded in F-PRISMA. Finally, we show that basic categorical tools can help to relate and to compose SAMs and PRISMA processes in an elegant way.     

Unsupervised learning with mixed numeric and nominal data

Presents a similarity-based agglomerative clustering (SBAC) algorithm that works well for data with mixed numeric and nominal features. A similarity measure proposed by D.W. Goodall (1966) for biological taxonomy, that gives greater weight to uncommon feature value matches in similarity computations and makes no assumptions about the underlying distributions of the feature values, is adopted to define the similarity measure between pairs of objects. An agglomerative algorithm is employed to construct a dendrogram, and a simple distinctness heuristic is used to extract a partition of the data. The performance of the SBAC algorithm has been studied on real and artificially-generated data sets. The results demonstrate the effectiveness of this algorithm in unsupervised discovery tasks. Comparisons with other clustering schemes illustrate the superior performance of this approach     

行为级模型功能比对验证的自动方法学

在混合信号芯片设计领域,Verilog/Systemverilog/VHDL等行为级模型被广泛应用于描述模拟和混合信号模块的电路特性,用以帮助实现更快速全面的全芯片功能验证。为了保证正确、有效和全面的全芯片功能验证,电路模块的行为级模型和晶体管级设计之间的功能比对验证(Behavior vs.Schematic,BVS)非常关键。在此之前,利用现有的EDA工具,只能进行逻辑状态的BVS矢量检查,而不能进行实数类型的矢量检查。为了更好地描述模拟和混合信号模块的行为特性,采用了Wreal模型和SV-UDT(Systemverilog-User Defined Type),因此对EDA工具提出了新的要求,需要其支持实数类型的矢量检查。本文描述了一种行为级模型功能比对验证的自动方法学,基于Cadence XPS仿真器的矢量检查功能,可以同时实现逻辑状态和实数类型的自动比对检查。实数类型矢量检查是向EDA供应商Cadence提出的一种新的概念和需求,且已经在XPS仿真器中成功实现。     

Capture-avoiding substitution as a nominal algebra

Substitution is fundamental to the theory of logic and computation. Is substitution something that we define on syntax on a case-by-case basis, or can we turn the idea of substitution into a mathematical object? We give axioms for substitution and prove them sound and complete with respect to a canonical model. As corollaries we obtain a useful conservativity result, and prove that equality-up-to-substitution is a decidable relation on terms. These results involve subtle use of techniques both from rewriting and algebra. A special feature of our method is the use of nominal techniques. These give us access to a stronger assertion language, which includes so-called ‘freshness’ or ‘capture-avoidance’ conditions. This means that the sense in which we axiomatise substitution (and prove soundness and completeness) is particularly strong, while remaining quite general.     

On the existence of nominal plants

In this paper we consider single-input single-output (SISO) linear time-invariant systems represented by their ‘meromorphic’ transfer functions, k(s). We assume that k(s) is representative of a given set of uncertainty containing k, and we would like to introduce conditions for determining if a nominal plant exists for k, which would then be used for both analysis and design. It is shown that uncertainty sets representing marginally stable (or unstable) dipoles do not possess nominal plants. Some concluding remarks and suggestions for future research are provided.