考虑遮挡的视频车辆跟踪

为了对遮挡情况下的运动车辆进行跟踪,提出一种基于分块的车辆跟踪算法。该算法将目标车辆以可重叠的方式划分为若干大小一致的子块。在分块的基础上估计所有子块的运动矢量,检测噪声运动矢量并进行调整,以减少运动矢量估计的误差,然后对子块进行移位以实现车辆跟踪。为了处理车辆间的遮挡现象建立了马尔可夫随机场描述子块之间的关系,利用欧氏距离定义块的邻域,并基于块的直方图构建能量函数,最后利用模拟退火法对能量函数进行优化,以对遮挡区域进行分割。实验结果表明,该算法能够对遮挡车辆进行准确跟踪。     

Estimation of a Nonlinear Intervention Phase Trajectory for Multiple-Baseline Design Data

A multilevel logistic model for estimating a nonlinear trajectory in a multiple-baseline design is introduced. The model is applied to data from a real multiple-baseline design study to demonstrate interpretation of relevant parameters. A simple change-in-levels (ΔLevels) model and a model involving a quadratic function (Quadratic) for the nonlinear intervention phase data were also estimated. In addition, a simulation study was conducted to assess Markov chain Monte Carlo estimation of the logistic model and compare its trajectory recovery with use of the ΔLevels and Quadratic models. While most of the logistic model's parameter values were recovered well, trajectory recovery was very reasonable using the simpler Quadratic model. Results are discussed along with recommendations for practitioners and directions for future research.     

Different Argentine Rural Extensionists' Mindsets and Their Practical Implications

Purpose: This paper reflects upon the practice of Argentine rural extensionists working in the extension public system through the process of identifying different rural extensionists' types of mindsets and comparing them with transfer of technology extension approach, dialogical processes of horizontal knowledge exchange, participatory perspectives and innovation system approach.

Design/Methodology/approach: A quali-quantitative investigation was conducted. Surveys containing closed and open questions were sent via email to rural extensionists. This allowed the researcher to identify their beliefs about different issues connected to extension practice. The sample was incidental (n = 219; 143 men, 76 women). Qualitative data was categorized and quantified. Finally, a two-steps cluster analysis was implemented.

Findings: Two types of rural extensionists' mindsets were identified, one of which relates to the transfer of technology approach and other to the dialogical/horizontal model, yet neither of them fitting the ideal of the most important extension institution of the country, which supports an innovation system approach.

Practical implications: Extensionists' practices and institutional ideals do not coincide. Reflexive training processes are required to make beliefs about rural extension explicit in order to build a contextually suitable extension proposal. Originality/Value: Through a quali-quantitative approach to the issue of rural extensionists' mindsets, this paper contributes to a better understanding of Argentine rural extensionists' practices.     

高职酒店管理专业“校企合作”新模式探索

校企合作是我国目前重要的高职人才培养模式,同时也是实现高校与企业共赢的途径。随着社会经济的发展,酒店行业、企业对校企合作人才培养模式提出了新的要求,本研究提出了校企共建、股份共赢、合作培养"第三方"人才、改革"2+1"模式等新的合作模式探索。     

Digital body preservation: Technique and applications

High-fidelity anatomical models can be produced with three-dimensional (3D) scanning techniques and as such be digitally preserved, archived, and subsequently rendered through various media. Here, a novel methodology—digital body preservation—is presented for combining and matching scan geometry with radiographic imaging. The technique encompasses joining layers of 3D surface scans in an anatomical correct spatial relationship. To do so, a computed tomography (CT) volume is used as template to join and merge different surface scan geometries by means of nonrigid registration into a single environment. In addition, the use and applicability of the generated 3D models in digital learning modalities is presented. Finally, as computational expense is usually the main bottleneck in extended 3D applications, the influence of mesh simplification in combination with texture mapping on the quality of 3D models was investigated. The physical fidelity of the simplified meshes was evaluated in relation to their resolution and with respect to key anatomical features. Large- and medium-scale features were well preserved despite extensive 3D mesh simplification. Subtle fine-scale features, particular in curved areas demonstrated the major limitation to extensive mesh size reduction. Depending on the local topography, workable mesh sizes ranging from 10% to 3% of the original size could be obtained, making them usable in various learning applications and environments.     

“信息系统管理的关键问题＂研究模式的发展与特征术——以1980—2012年关键问题研究报告的内容分析为基础

始于1980年的“信息系统管理的关键问题”研究在管理信息系统学科已经形成了较为完整的研究体系和研究模式。文章采用内容分析法对世界范围内29次最具代表性的相关研究进行梳理,将其32年的发展历史概括为奠基期、改良期和重塑期,并以此为基础,总结出关键问题研究模式的重要特征。     

基于马尔可夫模型的风险型客户预测与管理

客户是企业的重要资产之一,是企业实现利润的源泉。客户关系的发展形成一个完整的生命周期,处于生命周期形成阶段的客户往往要消耗较多的资源却甚少为企业创造价值,企业的投入具有风险性。本文对风险型客户发展过程中的特点进行分析,同时提出基于马尔科夫模型的风险型客户预测方法,掌握风险型客户在市场竞争过程中的市场占有率信息,从而为企业的战略决策提供支持。     

Business models for sustainable technologies: Exploring business model evolution in the case of electric vehicles

Sustainable technologies challenge prevailing business practices, especially in industries that depend heavily on the use of fossil fuels. Firms are therefore in need of business models that transform the specific characteristics of sustainable technologies into new ways to create economic value and overcome the barriers that stand in the way of their market penetration. A key issue is the respective impact of incumbent and entrepreneurial firms’ path-dependent behaviour on the development of such new business models. Embedded in the literature on business models, this paper explores how incumbent and entrepreneurial firms’ path dependencies have affected the evolution of business models for electric vehicles. Based on a qualitative analysis of electric vehicle projects of key industry players over a five-year period (2006–2010), the paper identifies four business model archetypes and traces their evolution over time. Findings suggest that incumbent and entrepreneurial firms approach business model innovation in distinctive ways. Business model evolution shows a series of incremental changes that introduce service-based components, which were initially developed by entrepreneurial firms, to the product. Over time there seems to be some convergence in the business models of incumbents and entrepreneurs in the direction of delivering economy multi-purpose vehicles.     

基于移动平均-马尔可夫链模型的上海市机场旅客吞吐量预测研究

为了更多的挖掘数据的信息,本文将移动平均与马尔可夫链模型结合,对马尔可夫链模型进行改进,以拟合结果为动态基准线来构建动态的马尔可夫链,并进行预测及平稳分布研究.利用上海市机场2008年1月至2013年10月的各月数据进行模型拟合,将拟合结果作为动态基准线,进行系统状态划分,确定状态转移概率矩阵.预测未来4个月的中值和区间,并根据马尔可夫链的遍历性和稳定性求出状态的平稳分布.实证表明,该方法的预测精度更高,并且具有较强的适用性和泛化性,具有较强的实用价值.