动态环境下机器人多目标路径规划蚂蚁算法

研究了一种新颖的动态复杂不确定环境下的机器人多目标路径规划蚂蚁算法。该方法首先根据蚂蚁觅食行为对多个目标点的组合进行优化,规划出一条最优的全局导航路径。在此基础上,机器人按照规划好的目标点访问顺序根据多蚂蚁协作局部路径算法完成局部路径的搜索。机器人每前进一步都实时地进行动态障碍物运动轨迹预测以及碰撞预测,并重新进行避碰局部路径规划。仿真结果表明,即使在障碍物非常复杂的地理环境,用该算法也能使机器人沿一条全局优化的路径安全避碰的遍历各个目标点,效果十分令人满意。     

The New About News: How Print,Online, Free,and Mobile Coconstruct New Audiences in Italy,France, Spain,the UK,and Germany

This paper presents cross‐national research on news readership diversification. We compare written news (print and free newspapers, online and mobile news services) audiences in the 5 most populous and industrialized European countries (Italy, France, Spain, the UK and Germany). Outlining a sociodemographic portrait of these different news users is important in order to understand the changes undergone inside the world of written news. We draw on a telephone survey carried out in 2009, using a representative population sample (N=7,255). The survey considers sociodemographic variables, including a range of social activities and attitudinal variables, television, computer, and mobile phone ownership, and Internet access and use. Findings show a rich, but volatile relationship between written news, audience behaviors, and community participation.     

Hazard: an expert system for screening environmental chemicals on carcinogenicity

Abstract: The purpose of this paper is to design an expert system or an intelligent procedure' that purports to screen hazard potentials of environmental chemicals on the basis of structure-activity relationships in the study of chemical carcinogenesis, particularly with respect to analysing the current state of known structural information about chemical carcinogens and predicting the possible carcinogenicity of untested chemicals An analysis of a computerised database of known carcinogens (knowledge base) is being performed using the structure-activity trees in order to test the validity of the tree as a classification scheme (inference engine) and to evaluate trends or patterns that may exist between chemical structure and specificity for target tissue, route of administration, and animal species. Practical applications of the structure-activity tree depend on its eventual validation as a predictor of carcinogenic activity.     

Determining Stakeholder Needs in the Workplace: How Mobile Technologies Can Help

Mobile technologies offer exciting new opportunities to improve important requirements processes. However, providing usable, useful mobile requirements engineering (RE) tools is challenging due to mobile devices' limitations and limited knowledge on successfully using mobile RE tools in the field. You can use the reported lessons learned as an initial guide to develop and use mobile RE tools successfully. We believe that mobile RE tools will complement rather than replace traditional approaches, and the combination of context-aware and conventional elicitation and negotiation approaches has the potential to improve the quality of requirements. Evaluation studies also revealed several issues, including biases arising from the limited information available on mobile devices; integrated training, process guidance, and tool support for analysts; and guidance for end users to discover and document their own requirements. Further work in the mobile RE field is needed to address these issues. Mobile RE tools help elicit stakeholder heeds in the workplace. The authors discuss lessons learned that practitioners can adopt and use in their work     

Mobile applications in an aging society: Status and trends

Today, many countries, including several European states, the USA, and Japan, are aging; both the number and the percentage of elderly people are increasing. To create a cohesive and inclusive intergenerational society, technological products and services must be adapted to the needs and preferences of these citizens. Mobile phones are promising tools to improve the quality of life for the elderly. This work presents a review of the status of mobile functionalities and applications that can satisfy the requirements and needs of older people and improve their quality of life. This analysis of the state of the art enables us to identify the strengths and weaknesses of the current systems as well as discover trends and promising future lines of research. This paper outlines several needs that should be met to improve the quality of research in this area. This work provides a basis for researchers, designers, and mobile phone service providers to think about the existing needs of the elderly, the developing trends in the field and the opportunities that mobile applications offer to improve the quality of life of the elderly and to support a cohesive and inclusive society.     

Mobile Search for a Black Hole in an Anonymous Ring

In this paper we address the problem of mobile agents searching for a highly harmful item (called a black hole) in a ring network. The black hole is a stationary process that destroys visiting agents upon their arrival without leaving any observable trace of such a destruction. The task is to have at least one surviving agent able to unambiguously report the location of the black hole. We consider different scenarios and in each situation we answer some computational as well as complexity questions. We first consider agents that start from the same home base (co-located). We prove that two such agents are necessary and sufficient to locate the black hole; in our algorithm the agents perform O(n log n) moves (where n is the size of the ring) and we show that such a bound is optimal. We also consider time complexity and show how to achieve the optimal bound of 2n - 4 units of time using n - 1 agents. We generalize our technique to establish a trade-off between time and number of agents. We then consider the case of agents that start from different home bases (dispersed) and we show that if the ring is oriented, two dispersed agents are still necessary and sufficient. Also in this case our algorithm is optimal in terms of number of moves (Θ(n log n)). We finally show that if the ring is unoriented, three agents are necessary and sufficient; an optimal algorithm follows from the oriented case.     

Traversable Region Estimation for Mobile Robots in an Outdoor Image

This paper describes a novel method to estimate appropriate traversable regions from an outdoor scene image. The traversable regions output by the proposed method reflect the common sense of people. For example, a candidate traversable region is “a paved road somewhat distant from the side ditch.” The input to the traversable region estimation is one color image. First, category is assigned to each pixel in the image. The categorization result is then input to the region estimator. Finally, the traversable region are estimated on the input image. An important aspect of this method is the application of two score functions in region estimation process. One score function places high value on categories selected as traversable paths by subjects. The other function places high value on categories that are not selected as traversable regions but are adjacent to categories with traversable paths. A combination of these two functions produces feasible estimation results. The effectiveness of the combined score functions was evaluated by experiments and a questionnaire.     

移动多媒体通信中一种自适应TuCM功率控制

为了解决自适应TuCM对时延敏感的问题,文章对截短信道倒置功率控制算法进行改进,提出了一种改进的功率控制算法。并利用数学拟合方法,对算法中参数ξ的选定进行了理论分析与实验仿真。结果表明,通过选择合适的参数ξ,采用改进的功率控制算法能够降低咱适应TuCM对时延的要求。     

ICA:一种基于混合智能算法的移动Agent路由算法

遗传算法具有快速随机的全局搜索能力,但对于系统中反馈信息利用却无能为力,求精确解效率低.改进型ACS(antcolony system)算法不仅具有分布式并行全局搜索能力,而且在很大程度上避免了候选解陷入局部极小并导致系统收敛到这一伪最优解从而停止进化的可能性,但存在初期信息匮乏,求解速度慢的缺点.为了改善移动Agent系统的迁移性能和执行效率,本文提出一种基于由遗传算法和改进型ACS算法组成的混合智能算法的移动Agent路由算法.该路由算法是汲取两种智能算法的优点,克服各自的缺陷.通过对TAP问题的仿真实验表明该算法取得了较好的效果.     

IDC：手机网络游戏迎来爆发期

随着中国智能手机市场的快速发展,大屏幕、高分辨率、全触屏技术改善了用户基于手机进行游戏操作的体验;3G网络的大规模建设使用户通过移动网络接入互联网的速度得到了大幅提升,为用户玩手机网络游戏奠定了网络基础;手机网络游戏开发商在近几年不断加大对手机网络游戏的研发投入,手机网络游戏的品质也得到了较大改进。在三方因素促进下,中国手机网络游戏用户数量大幅增长,     

IDC:手机网络游戏迎来爆发期

随着中国智能手机市场的快速发展,大屏幕、高分辨率、全触屏技术改善了用户基于手机进行游戏操作的体验;3G网络的大规模建设使用户通过移动网络接入互联网的速度得到了大幅提升,为用户玩手机网络游戏奠定     

Mobile phones as medical devices in mental disorder treatment: an overview

Mental disorders can have a significant, negative impact on sufferers’ lives, as well as on their friends and family, healthcare systems and other parts of society. Approximately 25 % of all people in Europe and the USA experience a mental disorder at least once in their lifetime. Currently, monitoring mental disorders relies on subjective clinical self-reporting rating scales, which were developed more than 50 years ago. In this paper, we discuss how mobile phones can support the treatment of mental disorders by (1) implementing human–computer interfaces to support therapy and (2) collecting relevant data from patients’ daily lives to monitor the current state and development of their mental disorders. Concerning the first point, we review various systems that utilize mobile phones for the treatment of mental disorders. We also evaluate how their core design features and dimensions can be applied in other, similar systems. Concerning the second point, we highlight the feasibility of using mobile phones to collect comprehensive data including voice data, motion and location information. Data mining methods are also reviewed and discussed. Based on the presented studies, we summarize advantages and drawbacks of the most promising mobile phone technologies for detecting mood disorders like depression or bipolar disorder. Finally, we discuss practical implementation details, legal issues and business models for the introduction of mobile phones as medical devices.     

The Demand for Post‐Katrina Disaster Aid: SBA Disaster Loans and Small Businesses in Mississippi

Following Hurricane Katrina, the United States government provided billions of dollars in loans to repair the damage caused by the hurricane. However, the specifics surrounding demand for these loans and the process of application and approval for Small Business Administration (SBA) loans have yet to be fully examined. We analyse the demand of small businesses for such loans and delve into the factors which are associated with success in obtaining loan funds following disaster. Results indicate several factors are important in all of the stages of the loan process: the income of the business, whether the business had insurance or received money in an insurance claim and the gender of the business owner.     

Snap Target: Investigating an Assistance Technique for Mobile Magic Lens Interaction With Large Displays

Modern handheld devices can act as “magic lenses” for public displays and enable camera-based real-time interaction with their contents, thus allowing for manifold interactive applications in public space. To learn more about the characteristics of common techniques and to provide guidelines for new ones, a comparative user study was conducted. With regard to two basic task types (selection and translation) and two typical devices (smartphone and tablet), three interaction techniques in-depth were evaluated: direct touch-based input (Touch), cross-hair targeting (Target), and a new technique based on a dynamic cross-hair on the screen that snaps to visible nearby screen objects (Snap Target). The study results indicate that successful interaction with the Touch technique strongly depends on the usage context: Although Touch enables fast selection, it incurs many errors when small targets have to be selected on a smartphone. Target supports such difficult selections better, but Snap Target proved to be most robust in both investigated task types. Also, users stated that they felt best supported by the latter technique. Cross-hair-based techniques, especially Snap Target, were found to be well suitable for scenarios where several device types need to be supported under similar conditions. Implications and further work are discussed.     

Communication-Aware Mobile Relaying via an AUV for Minimal Wait Time: A Broad Learning-Based Solution

<正>Dear Editor,This letter studies the communication-aware mobile relaying via an autonomous underwater vehicle(AUV) for minimal wait time. Compared with the analysis-based channel prediction solution, the proposed discrete Kirchhoff approximation solution has a higher estimation accuracy.     

How to Overcome Disorientation in Mobile Phone Menus: A Comparison of Two Different Types of Navigation Aids

The current study was concerned with the basic question of how to overcome users' disorientation when navigating through hierarchical menus in small-screen technical devices, as for example mobile phones. In these devices, menu functions are typically organized in a tree structure. Two different navigation aids were implemented into a computer simulation of a real mobile phone (Siemens S45®). The interface of the first navigation aid (the "category" aid) showed the name of the current category as well as a list of its contents. The interface of the other navigation aid (the "tree" aid) was identical to the first except that it also showed the parents and parent–parents of the current of the category and it indented the subcategories to emphasize the hierarchical structure. For the study, 16 younger (23–28 years) and 16 older adults (46–60 years) had to solve 9 common phone tasks twice consecutively to measure learnability. To gain further insight into user characteristics modulating navigation performance and possibly interacting with the utility of the navigation aids, we assessed users' verbal memory and spatial abilities. Dependent variables were task effectiveness (number of tasks solved) and efficiency (time on task, number of returns in menu hierarchy, and returns to the top). The results reveal a consistent and significant advantage of the tree aid for both age groups, an advantage that was larger for users with lower spatial abilities and older adults. In general, older adults had lower verbal memory and spatial abilities, which were found to account for their lower navigation performance. We assume that the strong advantage of the tree aid is due to the spatial information on the menu structure, which thus conveys survey knowledge. This allows users to form an adequate mental representation of the menu. It is recommended to add a navigation aid providing survey knowledge into the displays of small-screen devices to achieve better overall performance.     

Motion Planning Strategy for Finding an Object with a Mobile Manipulator in Three-Dimensional Environments

In this paper, we investigate the problem of minimizing the average time required to find an object in a known three-dimensional environment. We consider a 7-d.o.f. mobile manipulator with an 'eye-in-hand' sensor. In particular, we address the problem of searching for an object whose unknown location is characterized by a known probability density function. We present a discrete formulation, in which we use a visibility-based decomposition of the environment. We introduce a sample-based convex cover to estimate the size and shape of visibility regions in three dimensions. The resulting convex regions are exploited to generate trajectories that make a compromise between moving the manipulator base and moving the robotic arm. We also propose a practical method to approximate the visibility region in three dimensions of a sensor limited in both range and field of view. The quality and success of the generated paths depend significantly on the sensing robot capabilities. In this paper, we generate searching plans for a mobile manipulator equipped with a sensor limited in both field of view and range. We have implemented the algorithm and present simulation results.