How practice produces suboptimal heuristics that render backup instruments ineffective

The operation of machines typically requires attention to instruments that signal the state of the machine. One safeguard against primary instrument malfunction is to provide backup instruments, but this works only if the operators react to malfunction by switching attention to the backups. Little is known about the effect of negative outcomes or feedback on allocation of attention to backup instruments. Four experiments demonstrated that prior practice causes operators of a simulated machine to adapt to instrument malfunction by changing to a suboptimal decision rule rather than by reallocating attention to a different set of instruments. This fallacy appears linked to the operators' failures to notice feedback that they should switch during the simulations and operators' failures to correctly interpret outcome feedback following the simulations. The results raise theoretical questions and warn interface designers not to overrate backup instruments.     

How practice produces suboptimal heuristics that render backup instruments ineffective

The operation of machines typically requires attention to instruments that signal the state of the machine. One safeguard against primary instrument malfunction is to provide backup instruments, but this works only if the operators react to malfunction by switching attention to the backups. Little is known about the effect of negative outcomes or feedback on allocation of attention to backup instruments. Four experiments demonstrated that prior practice causes operators of a simulated machine to adapt to instrument malfunction by changing to a suboptimal decision rule rather than by reallocating attention to a different set of instruments. This fallacy appears linked to the operators' failures to notice feedback that they should switch during the simulations and operators' failures to correctly interpret outcome feedback following the simulations. The results raise theoretical questions and warn interface designers not to overrate backup instruments.     

Relevance feedback revisited: dealing with content and structure in XML documents

Relevance feedback (RF) is a technique that allows to enrich an initial query according to the user feedback. The goal is to express more precisely the user’s needs. Some open issues arise when considering semi-structured documents like XML documents. They are mainly related to the form of XML documents which mix content and structure information and to the new granularity of information. Indeed, the main objective of XML retrieval is to select relevant elements in XML documents instead of whole documents. Most of the RF approaches proposed in XML retrieval are simple adaptation of traditional RF to the new granularity of information. They usually enrich queries by adding terms extracted from relevant elements instead of terms extracted from whole documents. In this article, we describe a new approach of RF that takes advantage of two sources of evidence: the content and the structure. We propose to use the query term proximity to select terms to be added to the initial query and to use generic structures to express structural constraints. Both sources of evidence are used in different combined forms. Experiments were carried out within the INEX evaluation campaign and results show the effectiveness of our approaches.     

What artificial experts can and cannot do

One's model of skill determines what one expects from neural network modelling and how one proposes to go about enhancing expertise. We view skill acquisition as a progression from acting on the basis of a rough theory of a domain in terms of facts and rules to being able to respond appropriately to the current situation on the basis of neuron connections changed by the results of responses to the relevant aspects of many past situations. Viewing skill acquisition in this ways suggests how one can avoid the problem currently facing AI of how to train a network to make human-like generalizations. In training a network one must progress, as the human learner does, from rules and facts to wholistic responses. As to future work, from our perspective one should not try to enhance expertise as in traditional AI by attempting to construct improved theories of a domain, but rather by improving the learner's access to the relevant aspects of a domain so as to facilitate learning from experience.     

关于Web Page的语义挖掘研究

关于Web Page语义挖掘的目的主要是在现有网络挖掘的基础上对挖掘内容加上语义的表述从而达到提高挖掘的效果.主要先处理挖掘的数据源,然后对数据进行语义标注,建立本体,将本体实例化,形成语义数据库,利用现有的挖掘算法实现挖掘结果.最终得到相对于现有挖掘效果得到提高的结论.     

六足仿生机器人的设计与实现

所述六足仿生机器人基于SoC FPGA平台实现,结合了机械结构设计、六足步态控制、蓝牙传输技术、弯曲传感器、OpenCL图像处理加速、VR显示等诸多技术。ARM部分作为主控,存储摄像头视频图像,并调用FPGA模块对图像处理加速,通过路由器架设的局域网向VR眼镜输出视频流信息。FPGA部分用于接收蓝牙信号,驱动机器人手臂运动,摄像头拍摄角度切换以及六足行进。实际操作时操作者需佩戴自制的数据手套和VR眼镜。操作数据手套上的方向按键可控制机器人移动。数据手套的每个手指上安装有弯曲传感器,用于控制机械手臂跟随人手实时运动。VR眼镜中放置一个智能手机作为显示终端,实时显示机器人摄像头获取的画面。经过多次实际测试,操作者佩戴VR眼镜及数据手套均可远程操控机器人抓取置于复杂地形中的水瓶。     

Using a fuzzy approach to support financial analysis in the corporate acquisition process

In the global market place, many companies have had to adapt their strategies to meet significant challenges. A strategy adopted by some companies has been international expansion via acquisitions. The need for expert knowledge to determine an appropriate company to acquire has been complicated by the sheer size of the global market place. The costs associated with this in relation to time and personnel have created the need for a computerised expert system to be developed. This paper endeavours to show how a proposed fuzzy based system can assist in the identification of a company for acquisition. The authors discuss the manipulation of the magnitude of fuzzy membership functions to communicate priorities within the system. The fuzzy system is designed to assist financial experts in identifying a suitable company for acquisition in the corporate acquisition process. This includes the deliberate weighting of certain inputs and results above others in the decision-making process. The system attempts to learn and simulate the human precedence given to particular financial statistics in company analysis. The system uses the magnitude of the fuzzy membership functions to reflect the human precedence given to each financial ratio. This enables a particular company's strengths and weakness to be considered while concurrently considering their significance and relevance to the acquiring organisation. The system will enable a larger number of companies to be analysed in a more time and cost-effective manner. The development of this system is intended to illustrate that a fuzzy system can aid the financial experts of an acquiring organisation in the global acquisition process.     

Spreadsheet application to labor determination

During the test phase of new products in the fast food industry many factors have to be analyzed in order to ensure a smooth, full introduction into all the restaurants in the system. The impact of the new product on sales, service, inventory, quality, profit, and labor must be evaluated prior to system wide introduction. Arriving at a full and detailed answer to labor questions, involves the use of product cannibalization or attrition information, product preparation standards development, computer simulation to develop labor guidelines, as well as data collection for validation of the simulation results. An alternative to using computer simulation to develop labor guidelines is to use a spreadsheet application that enables the determination of the distribution of kitchen labor. This spreadsheet will determine the labor requirements at different sales levels prior to the product introduction in the test restaurants, as well as to system wide introduction. The first inputs to the spreadsheet use financial projections to develop initial labor guidelines for test restaurants to use. The next stage uses actual sales and cannibalization figures to determine labor guidelines prior to the rollout of the new product into all the restaurants in the system.     

Habituation effects in computer security warning

Security warning is a form of computer dialog communication used to inform the users on the risks of allowing random applications to run on a computer system. Accordingly, it is specifically designed to impersonate a legitimate security alerting function (e.g., notify, warn, and advice) to a user about the consequence effect of an action. However, most of the computer users tend to ignore those security warnings conveying the same message over and over again. This eventually leads to habituation. Considering the fact that there is a significant lack of focus paid to address this issue, the main objective of this article is to describe and summarize the related studies on users’ habituation to the security warnings. This article presents a systematic literature review to explore the current key issues, challenges, and the possible solutions related to habituation effects in security warnings. It is expected that this article could contribute to a more complete understanding of the habituation effects in security warnings and eventually bring benefits to the research communities or general publics.     

Applicant preferences for Web-based versus traditional job postings

The purpose of the current study was to assess the extent to which applicants preferred Web-based job postings to traditional paper-based materials. An integration of the traditional recruitment literature as well as the burgeoning literature related to the use of computer technology led to the development of two primary study hypotheses. First, applicants were expected to prefer Web-based job postings to more traditional paper postings. Second, applicants were expected to prefer jobs posted on Web pages of higher quality to those posted on pages of lower quality. Data collected from 92 undergraduate students provided support for the second hypothesis. Contrary to the first hypothesis, however, paper postings were preferred to those in a Web-based format. A discussion of the implications of these findings is presented along with recommendations for future research in the area.     

遗传规划算法在化合物设计、筛选研究中的应用

采用计算机科学中新兴的遗传规划算法思想，结合化学物质的本质特点，运用进化操作来实现化合物的合成设计和筛选。文中针对算法运用讨论了函数集、终止集问题，通过计算元素组成的字符串的化合价的结果来确定适应度函数，既符合化学学科的本质规律，又满足了算法的要求。通过复制、交换和突变操作，经过多代次的进化终止，取得了满意的结果。文章还针对其实用性，从化学本质出发，提出了建议和研究方向。可以说本文是遗传规划在化学化合物合成筛选中运用的成功探索，同时也为进一步研究打下了坚实的基础。     

基于随机游走的医学超声图像分割

医学超声图像不可避免地存在斑点噪声、弱边界等问题,很难达到满意的分割效果。随机游走算法对噪声具有鲁棒性,对弱边界有良好的提取能力。将此算法应用于医学超声图像分割,通过融合区域信息与用户指定的种子点信息,借助于电路模拟以及组合Dirichlet问题,可以得到每个非种子点到标记了目标点或者背景点的概率,并对其赋予概率中最大的种子点所对应的标记,从而实现图像的分割。实验结果表明,该方法对医学超声图像的分割是有效的。此算法通过求解稀疏的、对称的、正定的线性方程的系统来获得Dirichlet问题的解,使计算速度大为提高。     

A Closed-Loop Automatic Data-Mining Approach for Preventive Network Monitoring

As telecommunication networks grow in size and complexity, monitoring systems need to scale up accordingly. Alarm data generated in a large network are often highly correlated. These correlations can be explored to simplify the process of network fault management, by reducing the number of alarms presented to the network-monitoring operator. This makes it easier to react to network failures. But in some scenarios, it is highly desired to prevent the occurrence of these failures by predicting the occurrence of alarms before hand. This work investigates the usage of data mining methods to generate knowledge from historical alarm data, and using such knowledge to train a machine learning system, in order to predict the occurrence of the most relevant alarms in the network. The learning system was designed to be retrained periodically in order to keep an updated knowledge base.     

Retinal adaptation to non-uniform fields: average luminance or symbol luminance?

Various lighting and video display terminal design recommendations have been based on the assumption that the eye adapts to the average luminance of the field being viewed. Other evidence suggests that for irregular patterns the eye adapts to a level biased toward the peak luminance in the field being viewed. Subjects in this study adapted to uniform fields of varying average luminance and to two test patterns, one of which (dots) had a peak luminance equal to the brightest uniform field and an average luminance equal to the least bright uniform field. Time, to respond to a test pattern following adaptation to dots was intermediate between the two extreme uniform fields, but closer to that of the brighter field which had an average luminance equal to the test pattern's peak luminance. For that reason, proposed lighting differences based on image polarity or recommendations of positive image polarity do not appear to be warranted.     

Virtual surfaces and the influence of cues to surface shape on grasp

This research compared grasps to real surfaces with grasps to virtual surfaces, and used virtual surfaces to examine the role of cues to surface shape in grasp. The first experiment investigated the kinematics of overhand grasps to real and virtual objects. The results showed that, compared with grasps to real surfaces, grasps to virtual objects were different in the deceleration phase of the grasp movement and were more variable in their endpoint position. The second experiment used several measures to examine the relationship between the visual perception of a surface and the decision to grasp the surface with either an over-or underhand grasp. It was found that visual perception of the surface was consistent with the grasping decision. The third experiment used virtual surfaces to examine how the removal of visual cues to shape affected the decision to switch from over- to underhand grasp. Results showed that the orientation at which the decision switched was dependent on the visual information content. Overall, the results showed that subtle differences existed between the reach to grasp movements towards real and virtual surfaces and that the decision to choose between grasp types was dependent on the visual information used to depict the virtual surface. These results are discussed in relation to the design and use of input devices to enable manipulation of three-dimensional objects in virtual worlds.     

图像-文本相关性挖掘的Web图像聚类方法

为了实现Web图像检索结果的聚类,提出了一种Web图像的图聚类方法.首先定义了两种类型关联:单词与图像结点之间的异构链接以及单词结点之间的同构链接.为了克服传统的TF-IDF方法不能直接反映单词与图像之间的语义关联局限性,提出并定义了单词可见度(visibility)这一属性,并将其集成到传统的tf-idf模型中以挖掘单词-图像之间关联的权重.根据LDA(latent Dirichlet allocation)模型,单词-单词之间关联权重通过一个定义的主题相关度函数来计算.最后,应用复杂图聚类和二部图协同谱聚类等算法验证了在图模型上引入两种相关性关联的有效性,达到了改进了Web图像聚类性能的目的.     

提高计算机信息系统维护效率的策略探讨

计算机信息系统提升了整个信息时代的高速运转,帮助人们完场信息的采集、处理、存储、传输、检索等工作。如何帮助计算机用户节约更多的时间,是计算机信息系统维护工作需要继续改善的问题,抓住时间的时效性,提高信息的使用价值,就体现在这里。本为,问们将就如何提高计算机信息系统维护效率问题进行一系列的探讨分析。     

The integration of theory and practice in teaching designing for the screen

Future typographic and graphic designers will need to be able to design for a range of media, both to secure their role and to provide the necessary design expertise in technological environments. This paper proposes an approach to teaching which introduces theoretical issues within a practical design project to encourage the development of general concepts that can be transferred to different technologies. A specific project on designing for the screen is described, which is taught as part of a BA degree in Typography & Graphic Communication. In the context of this project, reasons for introducing theory are proposed, examples of the nature of the theory are given, and the methods used to introduce material are illustrated. A detailed account of one student's implementation of this project is used to demonstrate how theoretical issues can provide direction in a design task. However, careful consideration needs to be given to how theory and practice are integrated to encourage students to look beyond the short-term benefits of specific training to the development of more general knowledge.     

Three stage trade credit policy in a three-layer supply chain–a production-inventory model

The main purpose of this paper is to investigate the optimal replenishment lot size of supplier and optimal production rate of manufacturer under three levels of trade credit policy for supplier–manufacturer–retailer supply chain. The supplier provides a fixed credit period to settle the accounts to the manufacturer, while the manufacturer gives a fixed credit period to settle the account to the retailer and the retailer, in turn, also offers a credit period to each of its customers to settle the accounts. We assume that the supplier supplies the raw material to the manufacturer and sends back the defective raw materials to the outside supplier after completion of inspection at one lot with a sales price. The system always produces good items in the model. Also, we consider the idle times of supplier and manufacturer. Finally, numerical examples are provided to illustrate the behaviour and application of the model with graphical simulation.     

Interacting with team oriented plans in multi-robot systems

Team oriented plans have become a popular tool for operators to control teams of autonomous robots to pursue complex objectives in complex environments. Such plans allow an operator to specify high level directives and allow the team to autonomously determine how to implement such directives. However, the operators will often want to interrupt the activities of individual team members to deal with particular situations, such as a danger to a robot that the robot team cannot perceive. Previously, after such interrupts, the operator would usually need to restart the team plan to ensure its success. In this paper, we present an approach to encoding how interrupts can be smoothly handled within a team plan. Building on a team plan formalism that uses Colored Petri Nets, we describe a mechanism that allows a range of interrupts to be handled smoothly, allowing the team to efficiently continue with its task after the operator intervention. We validate the approach with an application of robotic watercraft and show improved overall efficiency. In particular, we consider a situation where several platforms should travel through a set of pre-specified locations, and we identify three specific cases that require the operator to interrupt the plan execution: (i) a boat must be pulled out; (ii) all boats should stop the plan and move to a pre-specified assembly position; (iii) a set of boats must synchronize to traverse a dangerous area one after the other. Our experiments show that the use of our interrupt mechanism decreases the time to complete the plan (up to 48 % reduction) and decreases the operator load (up to 80 % reduction in number of user actions). Moreover, we performed experiments with real robotic platforms to validate the applicability of our mechanism in the actual deployment of robotic watercraft.