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1.
The mobile botnet is a collection of compromised mobile devices that can remotely receive commands from the botmaster. Exploiting unique features of mobile networks and smartphones, mobile botnets pose a severe threat to mobile users, because smartphones have become an indispensable part of our daily lives and carried a lot of private information. With the development of cloud computing technologies, botmaster can utilize ubiquitous cloud technologies to construct robust and scalable C&C (command and control) channel for mobile botnet. In this paper, we propose Cloudbot, a novel mobile botnet, which outperforms existing mobile botnets in terms of robustness, controllability, scalability, and stealthiness. Although the basic idea of using cloud technologies seems straightforward, we explore the design space of exploiting such services and tackle several challenging issues to overcome the limitations of existing mobile botnets. We have implemented CloudBot by exploiting popular push services and cloud storage services, and evaluated it through extensive experiments. The results demonstrate not only the feasibility of CloudBot but also its advantages, such as stealthiness, robustness, and performance.  相似文献   

2.
In a context-aware ubiquitous learning environment, learning systems can detect students’ learning behaviors in the real-world with the help of context-aware (sensor) technology; that is, students can be guided to observe or operate real-world objects with personalized support from the digital world. In this study, an optimization problem that models the objectives and criteria for determining personalized context-aware ubiquitous learning paths to maximize the learning efficacy for individual students is formulated by taking the meaningfulness of the learning paths and the number of simultaneous visitors to each learning object into account. Moreover, a Heuristic Algorithm is proposed to find a quality solution. Experimental results from the learning activities conducted in a natural science butterfly-ecology course of an elementary school are also given to depict the benefits of the innovative approach.  相似文献   

3.
The advancement of wireless and mobile technologies has enabled students to learn in an environment that combines learning resources from both the real world and the digital world. Although such an approach has been recognized as being innovative and important, several problems have been revealed in practical learning activities. One major problem is owing to the lack of proper learning strategies or tools for assisting the students to acquire knowledge in such a complex learning scenario. Students might feel excited or engaged when using the mobile devices to learn in the real context; nevertheless, their learning achievements could be disappointing. To deal with this problem, this study presents a mobile learning system that employs Radio Frequency Identification (RFID) technology to detect and examine real-world learning behaviors of students. This study also utilizes each student’s responses from a two-tier test (i.e., multiple-choice questions in a two-level format) to provide personalized learning guidance (called two-tier test guiding, T3G). The experimental results from a natural science course of an elementary school show that this innovative approach is able to improve the learning achievements of students as well as enhance their learning motivation.  相似文献   

4.
Among the severe instructional shortcomings of lectures is their lack of interactivity. To overcome these problems, the learning environment of the interactive lecture is introduced, in which students and lecturer interact by using mobile computers in a wireless network. In an experimental study, 44 students participated in interactive and in conventional lecture meetings. A quiz service that allowed question to be posted, students’ answers to be evaluated, and the results to be presented graphically, was implemented on mobile computers. The participants rated the interactive condition better, also reporting higher levels of attention, activity and perceived learning success for this condition. Objective measures indicated a slight but insignificant difference toward better learning results in the interactive condition.  相似文献   

5.
Mobile and wireless communication technologies not only enable anytime and anywhere learning, but also provide the opportunity to develop learning environments that combine real-world and digital-world resources. Nevertheless, researchers have indicated that, without effective tools for helping students organize their observations in the field, the mobile learning performance could be disappointing. To cope with this problem, this study proposes an interactive concept map-oriented approach for supporting mobile learning activities. An experiment has been conducted on an elementary school natural science course to evaluate the effectiveness of the proposed method. The experimental results show that the proposed approach not only enhances learning attitudes, but also improves the learning achievements of the students.  相似文献   

6.
Contextual patterns in mobile service usage   总被引:3,自引:1,他引:2  
Mobile services differ from other services because of their temporal and spatial attributes. Mobile services additionally differ from each other in their value-added to the end-user. Some services—such as emailing and voice—are more business oriented. On the other hand, various free-time oriented services are provided in new smartphones, such as imaging and music playback. The present paper studies how mobile services are used in different contexts. For this, the paper develops a specialized algorithm that can be used with handset-based usage data acquired straight from end-users in an established panel study process. Educated guesses can be drawn on the user context based on the developed algorithm. In the present exercise usage contexts were divided into home, office and “on the move”. The algorithm is used with exemplary data from Finland and the UK covering 324 consumers in 2006. More than 70% of contextual use cases are correctly classified based on raw data. According to exemplary results particularly multimedia services are used “on the move”, whereas legacy mobile services experience more evenly distributed usage across all contexts. The algorithm that identifies context based on raw data provides a new angle to mobile end-user research. In the future, the accuracy of the algorithm will be improved with the integration of seamless cell-id logging and GPS data.  相似文献   

7.
The portability and immediate communication properties of mobile devices influence the learning processes in interacting with peers, accessing resources and transferring data. For example, the short message and browsing functions in a cell phone provide users with timely and adaptive information access. Although many studies of mobile learning indicate the pedagogical potential of mobile devices, the screen size, computational power, battery capacity, input interfaces, and network bandwidth are too restricted to develop acceptable functionality for the entire learning processes in a handheld device. Therefore, mobile devices can be adopted to fill the gap between Web-based learning and ubiquitous mobile learning. This study first creates a website, providing functions enabling learning to take place anytime and anywhere with any available learning device, for ubiquitous learning according to various properties of mobile devices. Nowadays, learners’ behaviors on a website can be recorded as learning portfolios and analyzed for behavioral diagnosis or instructional planning. A student model is then built according to the analytical results of learning portfolios and a concept map of the learning domain. Based on the student model and learners’ available learning devices, three modules are developed to build a ubiquitous learning environment to enhance learning performance via learning status awareness, schedule reminders and mentor recommendation. Finally, an experiment is conducted with 54 college students after implementation of the ubiquitous learning website. Experimental results indicate that the proposed system can enhance three learning performance indicators, namely academic performance, task accomplishment rates, and learning goals achievement rates.  相似文献   

8.
9.
Using ubiquitous computing in interactive mobile marketing   总被引:2,自引:1,他引:1  
Unique features of handheld devices, including their mobility, personalization and location-awareness engender new types of applications for mobile commerce, such as mobile advertising. Mobile marketing and advertising applications deliver promotional information to consumers based on their preferences and location. In this paper, we present SMMART, a context-aware, adaptive and personalized m-commerce application designed to deliver targeted promotions to the users of mobile devices about the products they like while guarding the users’ identity and protecting them from any unsolicited messages. Promotions distributed by SMMART are personalized by performing intelligent matching of the user’s shopping interests to current promotions available at a retail site. SMMART can adapt to changing preferences of its user by inconspicuously monitoring his or her shopping habits. We describe a fully functional prototype of SMMART built for Pocket PCs running Windows CE with .NET Compact Framework. This paper also presents a study demonstrating end-user usability and economic viability of SMMART.  相似文献   

10.
Context-aware ubiquitous learning (u-learning) is an innovative approach that integrates wireless, mobile, and context-awareness technologies to detect the situation of learners in the real world and provide adaptive support or guidance accordingly. In this paper, a context-aware u-learning environment is developed for guiding inexperienced researchers to practice single-crystal X-ray diffraction operations. Experimental results showed that the benefits of this innovative approach are that it is “systematic”, “authentic”, and “economical”, which implies the potential of applying it to complex science experiments, such as physics, chemistry or biotechnology experiments, for graduate and PhD students in colleges, or research workers in research institutes.  相似文献   

11.
Open learning environments, such as Massive Open Online Courses (MOOCs), often lack adequate learner collaboration opportunities; they are also plagued by high levels of drop-out. Introducing project-based learning (PBL) can enhance learner collaboration and motivation, but PBL does not easily scale up into MOOCS. To support definition and staffing of projects, team formation principles and algorithms are introduced to form productive, creative, or learning teams. These use data on the project and on learner knowledge, personality and preferences. A study was carried out to validate the principles and the algorithms. Students (n = 168) and educational practitioners (n = 56) provided the data. The principles for learning teams and productive teams were accepted, while the principle for creative teams could not. The algorithms were validated using team classifying tasks and team ranking tasks. The practitioners classify and rank small productive, creative and learning teams in accordance with the algorithms, thereby validating the algorithms outcomes. When team size grows, for practitioners, forming teams quickly becomes complex, as demonstrated by the increased divergence in ranking and classifying accuracy. Discussion of the results, conclusions, and directions for future research are provided.  相似文献   

12.
In this paper we describe a novel approach for interactive cinema based on context-aware narration using handheld computers. The paper describes both the artistic approach and the ubiquitous computing framework developed to realize the scenario. This framework has been used in various projects, including the described video production course at the ISNM, where five interactive cinema concepts have been developed and shown during a public demonstration. In our approach, a new type of user experience has been established by placing the viewer inside the movie’s physical locations during playback. Moreover, the developed ubiquitous computing framework provides a foundation for future work in the area of ad-hoc, service-oriented Ubicomp scenarios.  相似文献   

13.
针对无线传感器网络面向移动汇聚节点的自适应路由问题,为实现路由过程中对节点能量以及计算、存储、通信资源的优化利用,并对数据传输时延和投递率等服务质量进行优化,提出一种基于强化学习的自适应路由方法,设计综合的奖赏函数以实现对能量、时延和投递率等多个指标的综合优化。从报文结构、路由初始化、路径选择等方面对路由协议进行详细设计,采用汇聚节点声明以及周期性洪泛机制加速收敛速度,从而支持汇聚节点的快速移动。理论分析表明基于强化学习的路由方法具备收敛快、协议开销低以及存储计算需求小等特点,能够适用于能量和资源受限的传感器节点。在仿真平台中通过性能评估和对比分析验证了所述自适应路由算法的可行性和优越性。  相似文献   

14.
With the realization that more research is needed to explore external factors (e.g., pedagogy, parental involvement in the context of K-12 learning) and internal factors (e.g., prior knowledge, motivation) underlying student-centered mobile learning, the present study conceptually and empirically explores how the theories and methodologies of self-regulated learning (SRL) can help us analyze and understand the processes of mobile learning. The empirical data collected from two elementary science classes in Singapore indicates that the analytical SRL model of mobile learning proposed in this study can illuminate the relationships between three aspects of mobile learning: students’ self-reports of psychological processes, patterns of online learning behavior in the mobile learning environment (MLE), and learning achievement. Statistical analyses produce three main findings. First, student motivation in this case can account for whether and to what degree the students can actively engage in mobile learning activities metacognitively, motivationally, and behaviorally. Second, the effect of students’ self-reported motivation on their learning achievement is mediated by their behavioral engagement in a pre-designed activity in the MLE. Third, students’ perception of parental autonomy support is not only associated with their motivation in school learning, but also associated with their actual behaviors in self-regulating their learning.  相似文献   

15.
An approach to learning mobile robot navigation   总被引:1,自引:0,他引:1  
This paper describes an approach to learning an indoor robot navigation task through trial-and-error. A mobile robot, equipped with visual, ultrasonic and laser sensors, learns to servo to a designated target object. In less than ten minutes of operation time, the robot is able to navigate to a marked target object in an office environment. The central learning mechanism is the explanation-based neural network learning algorithm (EBNN). EBNN initially learns function purely inductively using neural network representations. With increasing experience, EBNN employs domain knowledge to explain and to analyze training data in order to generalize in a more knowledgeable way. Here EBNN is applied in the context of reinforcement learning, which allows the robot to learn control using dynamic programming.  相似文献   

16.
Mobile and ubiquitous learning are increasingly attracting academic and public interest, especially in relation to their application in higher education settings.The systematic analysis of 36 empirical papers supports the view that knowledge gains from instructionist learning designs are facilitated by distributed and more frequent learning activities enabled by push mechanisms. They also lend themselves to the activation of learners during classroom lectures. In addition, and as a particular advantage of mobile technology, “hybrid” designs, where learners create multimodal representations outside the classroom and then discussed their substantiated experiences with peers and educators, helped to connect learning in formal and more informal and personalized learning environments.Generally, empirical evidence that would favour the broad application of mobile and ubiquitous learning in higher education settings is limited and because mobile learning projects predominantly take instructionist approaches, they are non-transformatory in nature. However, by harnessing the increasing access to digital mobile media, a number of unprecedented educational affordances can be operationalised to enrich and extend more traditional forms of higher education.  相似文献   

17.
Abstract  The general aim of this study was to develop a platform-adaptive learning environment (xTask) and to evaluate its use. The software environment can be accessed by PC's or mobile devices, such as PDA's or Communicator. The empirical part of the study was carried out during May 2002 with 10 students between 21 and 50 years of age participating in a course on mobile device usability. In the study the xTask interface proved functional. The working processes show clearly that there were phases when the work was efficient with mobile devices, but students also felt that mobile devices were not ready to be the only platform for learning. They preferred PC's with wired networks, but admitted that PDA's could be used to support aspects of the learning processes. Generally, mobile technologies can bring some added value for network based learning, but they cannot replace traditional computers.  相似文献   

18.
The advancement of mobile and wireless communication technologies has encouraged an increasing number of studies concerning mobile learning, in which students are able to learn via mobile devices without being limited by space and time; in particular, the students can be situated in a real-world scenario associated with the learning content. Although such an approach seems interesting to the students, researchers have emphasized the need for well-designed learning support in order to improve the students’ learning achievements. Therefore, it has become an important issue to develop methodologies or tools to assist the students to learn in a mobile learning environment. Based on this perspective, this study proposes a formative assessment-based approach for improving the learning achievements of students in a mobile learning environment. A mobile learning environment has been developed based on this approach, and an experiment on a local culture course has been conducted in southern Taiwan to evaluate its effectiveness. The experimental results show that the proposed approach not only promotes the students’ learning interest and attitude, but also improves their learning achievement.  相似文献   

19.
Wireless network is crucial for the Mobile Transparent Computing (MTC), in which a mobile device without any Operating System (OS) support needs to load the demanded OSes and applications through accessing the wireless network connection. In this paper, a lightweight approach based on the Boot Management System (BMS) was proposed to ensure the wireless network connection before booting OS. In BMS, the Virtual File System (VFS) technology was used to drive the wireless network card and establish a stable network connection. A prototype of the BMS was tested on ARM11 hardware platform and the results demonstrate the validity of the BMS.  相似文献   

20.
ObjectiveCreate a visual mobile end user development framework, named Puzzle, which allows end users without IT background to create, modify and execute applications, and provides support for interaction with smart things, phone functions and web services.MethodsDesign of an intuitive visual metaphor and associated interaction techniques for supporting end user development in mobile devices with iterative empirical validation.ResultsOur results show that the jigsaw is an intuitive metaphor for development in a mobile environment and our interaction techniques required a limited cognitive effort to use and learn the framework. Integration of different modalities and usage of smart things was relevant for users.ConclusionPuzzle has addressed the main objective. The framework further contributes to the research on mobile end user development in order to create an incentive for users to go beyond consuming content and applications to start creating their own applications.PracticeUsage of a mobile end user development environment has the potential to create a shift from the conventional few-to-many distribution model of software to a many-to-many distribution model. Users will be able to create applications that fit their requirements and share their achievements with peers.ImplicationsThis study has indicated that the Puzzle visual environment has the potential to enable users to easily create applications and stimulate exploration of innovative scenarios through smartphones.  相似文献   

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