激光光条中心线提取研究综述

激光光条中心线提取在视觉测量、三维重建等领域具有重要的作用.介绍了不同类型的中心线提取模型,并且回顾了这些模型的转变和创新.具体来说,根据模型采用的核心算法,将中心线提取模型分为传统提取模型和基于深度学习的提取模型;传统中心线提取模型又分为极值模型、灰度重心模型、曲线拟合模型、基于Hessian矩阵的Steger模型和...     

Power series generalized nonlinear models

We introduce in this paper a new class of discrete generalized nonlinear models to extend the binomial, Poisson and negative binomial models to cope with count data. This class of models includes some important models such as log-nonlinear models, logit, probit and negative binomial nonlinear models, generalized Poisson and generalized negative binomial regression models, among other models, which enables the fitting of a wide range of models to count data. We derive an iterative process for fitting these models by maximum likelihood and discuss inference on the parameters. The usefulness of the new class of models is illustrated with an application to a real data set.     

支持装备维修训练的虚拟样机模型研究

按照层次化建模和按需求剪裁的思路,建立了一种新的虚拟样机模型框架,包括层次模型、外观模型、状态模型、功能模型、交互模型、关联关系模型和信息模型七部分。这种虚拟样机模型框架可以支持装备虚拟维修训练的各个环节,简化虚拟样机建模工作的复杂性和工作量。     

Constrained interactivity for relating multiple representations in science: When virtual is better than real

Virtual models are increasingly used in science education, especially in spatially demanding domains. However, few studies have directly compared the effectiveness of virtual and concrete models, or systematically characterized differences between them. Here, we compared students' accuracy and efficiency using virtual and concrete models to align and produce different representations in the domain of organic chemistry. Naïve undergraduate students learned the conventions of different molecular representations (diagrams and models) and then performed tasks that involved matching models to diagrams and using models to complete diagrams. The results indicated similar levels of accuracy for virtual and concrete models and greater efficiency for virtual models. Students preferred virtual models, but rated the usability of the two model types about equally. The efficiency benefit associated with using virtual models can be explained by their constrained interactivity, which prevented students from making task-irrelevant manipulations and increased the salience of the task-relevant information in the models.     

AR 型非线性时间序列模型的稳定性分析

在工程中,振幅依赖指数自回归模型、门限自回归模型和多项式自回归模型等一类具有ＡＲ型的非线性时间序列模型具有广泛的应用,为此给出了ＡＲ型非线性时间序列模型的稳定性条件及极限环存在条件,并对一些特殊模型进行了讨论。     

RH真空炉外精炼过程的优化

本文论述了过程计算机系统实现RH真空精炼的过程优化原理和模型。简要介绍了数学模型的基本概念，重点描述了RH真空处理数学模型中的状态模型和过程预测模型，以及控制系统的结构、软件配置及实现的功能。     

Protection of 3D models using cross recovery

This paper proposes a cross recovery scheme to protect a group of 3D models. The lost or damaged models can be reconstructed using the mutual support of the survived authenticated models. In the encoding phase, we convert a group of n given models (called host models) into n stego* models. The n stego* models would still preserve the appearance of the n host models. In the decoding phase, we divide the received models into two groups: authenticated vs. non-authenticated. Then, we rebuild the recovered models of the non-authenticated group by the mutual support of any t authenticated models (t < n is a given parameter). The experimental results show that the visual quality of our stego* models is very similar to that of the host models, and the size of the stego* models is also very similar to that of the host models. Moreover, after hacker’s attack or disk crash, if the number of attacked or crashed stego* models is not larger than n ? t, then the damaged or lost models can be recovered, and the recovered models still have acceptable quality. We also provide an equation which can estimate the suitable size of the recovered model in advance.     

Dual models for possibilistic regression analysis

Upper and lower regression models (dual possibilistic models) are proposed for data analysis with crisp inputs and interval or fuzzy outputs. Based on the given data, the dual possibilistic models can be derived from upper and lower directions, respectively, where the inclusion relationship between these two models holds. Thus, the inherent uncertainty existing in the given phenomenon can be approximated by the dual models. As a core part of possibilistic regression, firstly possibilistic regression for crisp inputs and interval outputs is considered where the basic dual linear models based on linear programming, dual nonlinear models based on linear programming and dual nonlinear models based on quadratic programming are systematically addressed, and similarities between dual possibilistic regression models and rough sets are analyzed in depth. Then, as a natural extension, dual possibilistic regression models for crisp inputs and fuzzy outputs are addressed.     

力/触觉再现中柔性物体可视化物理形变模型研究进展

力/触觉再现技术的出现,为虚拟现实开辟了全新的应用领域,促使基于物理意义的柔性物体形变建模成为一个研究热点.系统地讨论了近年来基于物理意义的柔性物体形变建模方法,分析了基于直接构建的模型、基于连续介质力学的模型和其他相关模型的基本思想和优缺点.对这些建模方法的性能进行了细致的比较,并探讨了柔性物体物理形变建模的未来发展趋势.     

Solving Infinite Horizon Growth Models with an Environmental Sector

This paper concerns computational models in environmental economics andpolicy, particularly so-called integrated assessment models. For themost part, such models are simply extensions of standard neoclassicalgrowth models, extended by including the environment and pollutiongeneration. We review the structure of integrated assessment models,distinguishing between finite horizon and infinite horizon models, bothdeterministic and stochastic. We present a new solution algorithm forinfinite horizon integrated assessment models, relying on a neural netapproximation of the value function within an iterative version of theBellman equation.     

A uniform approach for access control and business models with explicit rule realization

Access control is an important part of security in software, such as business applications, since it determines the access of users to objects and operations and the constraints of this access. Business and access control models are expressed using different representations. In addition, access control rules are not generally defined explicitly from access control models. Even though the business model and access control model are two separate modeling abstractions, they are inter-connected as access control is part of any business model. Therefore, the first goal is to add access control models to business models using the same fundamental building blocks. The second goal is to use these models and define general access control rules explicitly from these models so that the connection between models and their realizations are also present. This paper describes a new common representation for business models and classes of access control models based on the Resource–Event–Agent (REA) modeling approach to business models. In addition, the connection between models and their represented rules is clearly defined. We present a uniform approach to business and access control models. First, access control primitives are mapped onto REA-based access control patterns. Then, REA-based access control patterns are combined to define access control models. Based on these models, general access control rules are expressed in Extended Backus–Naur Form.     

基于极限学习机的组合软件可靠性模型研究

针对单一软件可靠性模型适应性不强和数据驱动模型稳定性较差的问题,本文选取3种典型软件可靠性模型作为基模型,利用极限学习机对基模型的预测结果进行加权优化,得到组合软件可靠性模型,实现经典软件可靠性模型和人工智能算法的有机结合。通过对3组失效数据进行仿真实验,并与单一模型、基于其他神经网络算法的组合模型以及数据驱动模型的预测结果进行对比,验证了本文模型能够有效地提升预测精度和模型的适应性。     

Usability of concrete and virtual models in chemistry instruction

Virtual models are increasingly common in the modern science classroom, however little is known about the relative effectiveness of virtual and concrete models. We developed a virtual modeling system and tested the benefit of haptic cue fidelity, controlling for many other perceptual differences between concrete and virtual models. In two studies we directly compared performance of students using this virtual model and using concrete models for tasks in the domain of organic chemistry. Students used either virtual or concrete models to match diagrams of molecules or compare the structures of molecules represented by models and diagrams. The results indicated similar levels of accuracy and similar ratings of usability for virtual and concrete models but no effect of haptic cue fidelity. Greater efficiency with virtual models was observed when students matched diagrams and models, and this efficiency transferred to later use of concrete models. The efficiency benefit is attributed to interactive constraints of the hand-held interface to the virtual model, which helped students identify task-relevant information in the model and limited them to performing the most task-relevant interactions with the models.     

时空数据模型的研究与进展

时态地理信息系统(TGIS)以表达、管理和分析动态变化的地理现象为目的,其核心是时空数据库,因此对时空数据库的理论基础——时空数据模型的研究十分必要。目前的时空数据模型主要有简单模型、时空联合模型、时空属三域模型、基于对象/特征的模型和基于事件/过程的模型等。首先对这些模型进行了回顾,对其优缺点和侧重点进行了分析对比,然后在此基础上对时空数据模型的进一步研究方向进行了剖析。     

Affect prediction from physiological measures via visual stimuli

This study aims to predict different affective states via physiological measures with three types of computational models. An experiment was designed to elicit affective states with standardized affective pictures when multiple physiological signals were measured. Three data mining methods (i.e., decision rules, k-nearest neighbours, and decomposition tree) based on the rough set technique were then applied to construct prediction models from the extracted physiological features. We created three types of prediction models, i.e., gender-specific (male vs. female), culture-specific (Chinese vs. Indian vs. Western), and general models (participants with different genders and cultures as samples), and direct comparisons were made among these models. The best average prediction accuracies in terms of the F₁ measures (the harmonic mean of precision and recall) were 60.2%, 64.9%, 63.5% for the general models with 14, 21, and 42 samples, 78.0% for the female models, 75.1% for the male models, 72.0% for the Chinese models, 73.0% for the Indian models, and 76.5% for the Western models, respectively. These results suggested that the specific models performed better than did the general models.     

Composite performance and dependability analysis

Composite performance and dependability analysis is gaining importance in the design of complex, fault-tolerant systems. Markov reward models are most commonly used for this purpose. In this paper, an introduction to Markov reward models including solution techniques and application examples is presented. Extensions of Markov reward models to semi-Markov reward models are also mentioned. A brief discussion of how task completion time models and models of queues with breakdowns and repairs relate to Markov reward models is also given.     

Do Markov-switching models capture nonlinearities in the data?: Tests using nonparametric methods

Markov-switching models have become popular alternatives to linear autoregressive models. Many papers which estimate nonlinear models make little attempt to demonstrate whether the nonlinearities they capture are of interest or if the models differ substantially from the linear option. By simulating the models and nonparametrically estimating functions of the simulated data, we can evaluate if and how the nonlinear and linear models differ.     

Web浏览预测的Markov模型综述

Web访问模式挖掘研究的一个重要议题是Web浏览预测,Markov模型是一种经典的Web浏览预测模型.本文首先介绍了基本Markov浏览预测模型,包括基本Markov浏览行为模型,模型的学习训练及其在Web浏览预测问题中的应用;然后重点分析了扩展的Markov浏览预测模型,包括一序组合预测模型、高序模型、混合模型、隐Mark-ov模型、连续时间Markov模型等,综述了各种扩展模型所考虑的浏览预测问题的本质出发点、模型的学习方法及预测方法,最后分析了Markov浏览预测模型有待进一步研究的问题.     

Stability and stabilizability of fuzzy-neural-linear controlsystems

This paper discusses stability analysis of fuzzy-neural-linear (FNL) control systems which consist of combinations of fuzzy models, neural network (NN) models, and linear models. The authors consider a relation among the dynamics of NN models, those of fuzzy models and those of linear models. It is pointed out that the dynamics of linear models and NN models can be perfectly represented by Takagi-Sugeno (T-S) fuzzy models whose consequent parts are described by linear equations. In particular, the authors present a procedure for representing the dynamics of NN models via T-S fuzzy models. Next, the authors recall stability conditions for ensuring stability of fuzzy control systems in the sense of Lyapunov. The stability criteria is reduced to the problem of finding a common Lyapunov function for a set of Lyapunov inequalities. The stability conditions are employed to analyze stability of FNL control systems. Finally, stability analysis for four types of FNL control systems is demonstrated