A hybrid recommendation technique based on product category attributes

Recommender systems are powerful tools that allow companies to present personalized offers to their customers and defined as a system which recommends an appropriate product or service after learning the customers’ preferences and desires. Extracting users’ preferences through their buying behavior and history of purchased products is the most important element of such systems. Due to users’ unlimited and unpredictable desires, identifying their preferences is very complicated process. In most researches, less attention has been paid to user’s preferences varieties in different product categories. This may decrease quality of recommended items. In this paper, we introduced a technique of recommendation in the context of online retail store which extracts user preferences in each product category separately and provides more personalized recommendations through employing product taxonomy, attributes of product categories, web usage mining and combination of two well-known filtering methods: collaborative and content-based filtering. Experimental results show that proposed technique improves quality, as compared to similar approaches.     

Multi-level differential surface representation based on local transformations

One crucial issue of multi-resolution surface representations is how to effectively record and reconstruct geometric details among surface levels. Standard multi-resolution techniques encode details directly as local displacements in the vertices, and may produce unplausible results when the base level endures large deformations. In this paper we propose an alternative detail representation and reconstruction scheme, based on local transformations on a per-triangle basis. While more storage is required, recording details as local transformations favors global coupling of geometric details and allows for large-scale surface manipulations. By modeling the scale components of the surface modifications as a set of deforming factors, we achieved detail-preserving reconstruction results naturally under very large deformations. Comprehensive experimental results verify the efficiency and robustness of our approach. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

A hybrid scheme for action representation

Strong deficiencies are present in symbolic models for action representation and planning, regarding mainly the difficulty of coping with real, complex environments. These deficiencies can be attributed to several problems, such as the inadequacy in coping with incompletely structured situations, the difficulty of interacting with visual and motorial aspects, the difficulty in representing low-level knowledge, the need to specify the problem at a high level of detail, and so on. Besides the purely symbolic approaches, several nonsymbolic models have been developed, such as the recent class of subsym-bolic techniques. A promising paradigm for the modeling of reasoning, which combines features of both symbolic and analogical approaches, is based on the construction of analogical models of the reference for the internal representations, as introduced by Johnson-Laird. In this work, we propose a similar approach to the problem of knowledge representation and reasoning about actions and plans. We propose a hybrid approach, symbolic and analogical, in which the inferences are partially devolved to measurements on analogical models generated starting from the symbolic representation. the interaction between the symbolic and the analogical level is due to the fact that procedures are connected to some symbols, allowing generating, updating, and verifying the mental model. the hybrid model utilizes, for the symbolic component, a representation system based on the distinction between terminological and assertional knowledge. the terminological component adopts a SI-Net formalism, extended by temporal primitives. the assertional component is a subset of first-order logics. the analogical representation is a set of concurrent procedures modeling parts of the world, action processes, simulations, and metaphors based on force fields concepts. A particular case study, regarding the problem of the assembly of a complex object from parts, is taken as an experimental paradigm. © 1993 John Wiley Sons, Inc.     

基于本体的工艺准备信息表达方法研究

为了实现工艺准备过程中信息的集成与共享,提出了将本体思想应用于工艺准备过程.建立了面向本体技术的工艺准备信息模型,描述了工艺准备领域本体及其结构,并给出了领域本体的形式化定义.为了解决领域本体一致性问题,给出了领域本体相似性计算方法,并设计了领域本体合并规则,最后通过一个应用实例验证了方法的有效性.     

基于混合染色体的带钢缺陷图像分类方法研究

为了保证带钢缺陷分类的实时性和准确性,提出了一种基于混合染色体的带钢缺陷图像分类方法。该方法不仅优化了支持向量机SVM中核函数参数、惩罚因子,并且对核函数、输入的特征向量进行了选择。除此之外,该方法融合了遗传算法和SVM,用遗传算法优化影响SVM的核函数参数、惩罚因子、输入特征和核函数;同时,用SVM建立的分类模型的分类准确率限制遗传算法的进化方向,彼此制约和促进,最终确定最优分类模型。实验结果表明,基于混合染色体的带钢缺陷图像分类方法建立的分类模型能实时、准确地对带钢缺陷图像进行分类。     

A novel hybrid approach based on sub-pattern technique and whitened PCA for face recognition

Recently, in a task of face recognition, some researchers presented that independent component analysis (ICA) Architecture I involves a vertically centered principal component analysis (PCA) process (PCA I) and ICA Architecture II involves a whitened horizontally centered PCA process (PCA II). They also concluded that the performance of ICA strongly depends on its involved PCA process. This means that the computationally expensive ICA projection is unnecessary for further process and involved PCA process of ICA, whether PCA I or II, can be used directly for face recognition. But these approaches only consider the global information of face images. Some local information may be ignored. Therefore, in this paper, the sub-pattern technique was combined with PCA I and PCA II, respectively, for face recognition. In other words, two new different sub-pattern based whitened PCA approaches (which are called Sp-PCA I and Sp-PCA II, respectively) were performed and compared with PCA I, PCA II, PCA, and sub-pattern based PCA (SpPCA). Then, we find that sub-pattern technique is useful to PCA I but not to PCA II and PCA. Simultaneously, we also discussed what causes this result in this paper. At last, by simultaneously considering global and local information of face images, we developed a novel hybrid approach which combines PCA II and Sp-PCA I for face recognition. The experimental results reveal that the proposed novel hybrid approach has better recognition performance than that obtained using other traditional methods.     

A hybrid recommendation system based on profile expansion technique to alleviate cold start problem

Multimedia Tools and Applications - Recommender systems are one of the information filtering tools which can be employed to find interest items of users. Collaborative filtering is one of the...     

Slantlet based hybrid watermarking technique for medical images

Multimedia Tools and Applications - Watermarking techniques are widely used for copyright protection, confidentiality and integrity issues in medical field. Reversibility, robustness, embedding...     

A circuit representation technique for automated circuit design

We present a method of automatically generating circuit designs using evolutionary search and a set of circuit constructing primitives arranged in a linear sequence. This representation has the desirable property that virtually all sets of circuit-constructing primitives result in valid circuit graphs. While this representation excludes certain circuit topologies, it is capable of generating a rich set of them including many of the useful topologies seen in hand-designed circuits. Our system allows circuit size (number of devices), circuit topology, and device values to he evolved. Using a parallel genetic algorithm and circuit simulation software, we present experimental results as applied to three analog filter and two amplifier design tasks. In all tasks, our system is able to generate circuits that achieve the target specifications. Although the evolved circuits exist as software models, detailed examinations of each suggest that they are electrically well behaved and thus suitable for physical implementation. The modest computational requirements suggest that the ability to evolve complex analog circuit representations in software is becoming more approachable on a single engineering workstation     

基于拓扑反变的路面裂纹检测技术

为了提高公路的养护效率,减少维护成本,实现路面裂纹检测智能化,本文根据路面裂纹的多个本征属性,构建复杂数据集的度量空间,组成拓扑空间,推导路面裂纹原始空间到目标空间的拓扑反变关系。利用拓扑反变关系实现裂纹数据集的特征提取,为路面裂纹的识别奠定基础,且根据此方法设计出了系统的主要结构组成。最后通过实验分析了这种新的路面裂纹检测方法的去噪性能和识别能力。     

基于Wasserstein GAN的文档表示模型

文档表示模型可以将非结构化的文本数据转化为结构化数据,是多种自然语言处理任务的基础,而目前基于词的模型在文档表示任务中有着无法直接表示文档的缺陷。针对此问题,基于生成对抗网络GAN可以使用两个神经网络进行对抗学习,从而很好地学习到原始数据分布的特点,提出了文档表示模型WADM,使用去噪自编码器作为其判别网络,由其隐层直接得到文档的分布表示。实验表明,WADM能够准确抽取文档特征,相比基于词的模型具有更强的文档表示能力。     

Constrained optimization based on hybrid evolutionary algorithm and adaptive constraint-handling technique

A novel approach to deal with numerical and engineering constrained optimization problems, which incorporates a hybrid evolutionary algorithm and an adaptive constraint-handling technique, is presented in this paper. The hybrid evolutionary algorithm simultaneously uses simplex crossover and two mutation operators to generate the offspring population. Additionally, the adaptive constraint-handling technique consists of three main situations. In detail, at each situation, one constraint-handling mechanism is designed based on current population state. Experiments on 13 benchmark test functions and four well-known constrained design problems verify the effectiveness and efficiency of the proposed method. The experimental results show that integrating the hybrid evolutionary algorithm with the adaptive constraint-handling technique is beneficial, and the proposed method achieves competitive performance with respect to some other state-of-the-art approaches in constrained evolutionary optimization.     

A hybrid,decidable, logic-based knowledge representation system1

The major problem with using standard first-order logic as a basis for knowledge representation systems is its undecidability. A variant of first-order tautological entailment, a simple version of relevance logic, has been developed that has decidable inference and thus overcomes this problem. However, this logic is too weak for knowledge representation and must be strengthened. One way to strengthen the logic is to create a hybrid logic by adding a terminological reasoner. This must be done with care to retain the decidability of the logic as well as its reasonable semantics. The result, a stronger decidable logic, is used in the design of a hybrid, decidable, logic-based knowledge representation system.     

Selectively meshed surface representation

Surface rendering is an important technique for volume visualization. Any surface rendering algorithm has two phases—surface generation and rendering. We present a new surface rendering algorithm, which focuses on constructing the surface in a manner that speeds up the rendering phase. The motivation behind this is to reduce the response time for surface manipulations such as interactive rotations. We utilize a MC-like (Marching Cubes) approach to calculate the intersection points and their normals for each cube. But we dynamically link the intersection points to form triangles within the cube according to the locations of the last and the next visited neighboring cubes so that a good meshed surface can be generated. The difficulty with such an approach is that thousands of special cases need to be considered. But, we have found that the occurrence of five specific configurations out of the 14 basic MC cube configurations account for over 95% of all the cubes intersected by the iso-surface in most data sets. We process cubes belonging to these five configurations in a mesh mode, and the rest are processed in a non-mesh mode. As a result, the number of special cases are reduced substantially. Then a very careful analysis of the five configurations for mesh processing leads to just 136 cases, which makes the algorithm very simple. Test results show that the rendering time is almost halved compared to the time required for the rendering of a non-meshed surface generated by MC.     

A technique for precise depth representation in stereoscopic display

In observing a virtual 3D object displayed stereoscopically on a large screen, there is often a difference between the calculated depth and the perceived depth. This paper presents a method for reducing such differences of depth. To do this, we modify both the viewing position and the screen position in the stereoscopic calculation. The optimal amount of modification was determined from sample values of depth differences. The effectiveness of the proposed method is discussed on the merits of the experimental results. This technique decreased the average difference from 4.3 mm to 1.3 mm.     

Advanced Geometric Modeler with Hybrid Representation

An advanced geometric modeler GEMS4.0 has been developed,in which feature representation is used at the highest level abstraction of a product model.Boundary representation is used at the bottom level,while CSG model is adopted at the median level.A BRep data structure capable of modeling non-manifold is adopted.UNRBS representation is used for all curved surfaces,Quadric surfaces have dual representations consisting of their geometric data such as radius,center point,and center axis.Boundary representation of free form surfaces is easily built by sweeping and skinning method with NURBS geometry.Set operations on curved solids with boundary representation are performed by an evaluation process consisting of four steps.A file exchange facility is provided for the conversion between product data described by STEP and product information generated by GEMS4.0.     

基于核稀疏表示的属性选择算法

为解决高维数据在分类时造成的“维数灾难”问题,提出一种新的将核函数与稀疏学习相结合的属性选择算法。具体地,首先将每一维属性利用核函数映射到核空间,在此高维核空间上执行线性属性选择,从而实现低维空间上的非线性属性选择;其次,对映射到核空间上的属性进行稀疏重构,得到原始数据集的一种稀疏表达方式;接着利用L 1范数构建属性评分选择机制,选出最优属性子集;最后,将属性选择后的数据用于分类实验。在公开数据集上的实验结果表明,该算法能够较好地实现属性选择,与对比算法相比分类准确率提高了约3%。