跨平台框架下基于移动感知的智慧公交应用研究

为了解决在没有城市实时公交车数据的情况下实现智慧公交实时报站与到站提醒服务,提出利用开源的公交线路信息与移动终端的感知数据融合的解决方案。设计了基于Haversine的最近站点自动生成算法和基于心跳包机制的站点实时监测与到站提醒算法;通过优化距离计算公式降低地理空间距离计算的时间复杂度,从而提升算法的性能;最后利用移动跨平台框架APPCan实现智慧公交APP。     

可信移动平台身份管理框架

针对网络用户身份管理难题及现有的身份管理方案存在的不足,基于可信移动平台完整性校验、保护存储、域隔离和访问控制以及远程平台校验等安全特性,提出了可信移动平台身份管理方案和协议;构建了对应于口令、证书、指纹等认证方式的身份矩阵;实现了多种方式的身份认证、身份认证审计记录,主密钥、审计密钥、平台AIK私钥的加密存储,以及移动平台的可信验证、加密身份的还原和服务提供者身份标志的查找定位,并实现了身份信息和认证数据的加密传输;进行了安全性分析,结果表明该方案在保护用户身份信息安全的前提下,大大减轻了用户身份管理的     

面向移动平台的消息通讯服务设计与实现

由于移动平台网络和能耗方面的限制,应用开发者实现并维护一个移动端与服务器端可靠的、低能耗的消息通讯服务代价较高.面向移动平台的消息通讯服务为移动应用提供了即时的、可靠的消息通讯.同时结合移动端上下文信息丰富的特点,消息通讯服务提供了上下文情景感知的消息通讯方式.实验表明了此服务的可行性和低能耗特点.     

一种基于突变流量的在野黑产应用采集方法

随着经济社会的快速发展,互联网黑色产业(也称互联网地下产业,以下简称网络黑产)对人民群众的生产生活带来的影响也在快速扩大.近年来,移动互联网的兴起使以诈骗、博彩和色情为主的网络黑产移动应用(APP)变得更加猖獗,亟待采取有效措施进行管控.目前研究人员针对黑产应用的研究较少,其原因是由于执法部门持续对传统黑产应用分发渠道的打击,已有的通过基于搜索引擎和应用商店的采集方法的效果不佳,缺乏大规模具有代表性的在野黑产应用数据集已经成为开展深入研究的一大掣肘.为此,本文尝试解决在野黑产应用大规模采集的难题,为后续深入全面分析黑产应用及其生态提供数据支撑.本文提出了一种基于突变流量分析的黑产应用批量捕获方法,以黑产应用分发的关键途径为抓手,利用其具有的突变和伴随流量特点,批量快速发现正处于传播阶段的新兴在野黑产应用,为后续实时分析和追踪提供数据基础.在测试中,本方法成功获取了3,439条应用下载链接和3,303个不同的应用.捕获的移动应用中,不但有91.61%的样本被标记为恶意软件,更有98.14%的样本为首次采集发现的零天应用.上述结果证明了本文提出的方法在黑产应用采集方面的有效性.     

oDect: an RFID‐based object detection API to support applications development on mobile devices

The RFID technology is becoming ever more popular in the development of ubiquitous computing applications. A full exploitation of the RFID potential requires the study and implementation of human–computer interaction (HCI) modalities to be able to support wide usability by the target audience. This implies the need for programming methodologies specifically dedicated to support the easy and efficient prototyping of applications to have feedback from early tests with users. On the basis of our field‐working experience, we have designed oDect, a high‐level language and platform‐independent application programming interface (API), ad hoc designed to meet the needs of typical applications for mobile devices (smart phones and PDAs). oDect aims at allowing application developers to create their prototypes focusing on the needs of the final users, without having to care about the low‐level software that interacts with the RFID hardware. Further, in an end‐user developing (EUD) approach, oDect provides specific support for the application end‐user herself to cope with typical problems of RFID applications in detecting objects. We describe in detail the features of the API and discuss the findings of a test with four programmers, where we analyse and evaluate the use of the API in four sample applications. We also present results of an end‐user test, which investigated strengths and weaknesses of the territorial agenda (TA) concept. The TA is an RFID‐based citizen guide that aids—through time‐ and location‐based reminders—users in their daily activities in a city. The TA directly exploits EUD features of oDect, in particular concerning the possibility of linking detected objects with custom actions. Copyright © 2008 John Wiley & Sons, Ltd.     

基于Android平台的移动图书馆设计与开发

设计并实现了基于Android平台的移动图书馆系统,研究了其系统架构、关键技术、功能模块、开发环境和系统运行界面。系统由客户端和服务器端两部分构成,采用分层设计的理念,有效地降低了各个模块之间的耦合性,明确各个模块的职责,进而增强了系统的可扩展性。     

An application framework for developing collaborative handheld decision-making tools

This paper describes an application framework supporting collaborative handheld decision-making (CHDM). The main characteristics of the framework are: (1) extensive usage of visual elements and gestures; and (2) independence from specific decision-making methods, processes and tasks. The research departed from the analysis and systematisation of several CHDM scenarios, highlighting repeatable behaviour across multiple decision-making contexts. From these scenarios, we distilled a coherent set of common functional requirements organised in three main categories: process, macro- and micro-functionality. The proposed framework has been validated at length through the development of several CHDM tools. Six different tools are described in the paper. The main contribution of this work is a common foundation for developing CHDM tools.     

手机游戏开发架构的研究

传统手机游戏开发架构中存在着3个亟待解决的问题:一是单个服务器资源易于衰竭;二是多线程间的同步和互斥耗费资源严重;三是服务器不能弹性地管理线程资源.为解决这些问题,提出了一种新的手机游戏开发架构,并详细说明这一架构中的负荷迁徙模块、基于I/O完成端口的线程池模块和消息模块.该架构较好地解决了传统开发架构中单个服务器资源易于衰竭,多线程间的同步和互斥所引起巨大的系统资源开销,及服务器不能弹性地管理线程资源等问题.实验结果表明,新的架构具有较好的效果.     

A new open source platform for lowering the barrier for environmental web app development

The interactive nature of web applications or “web apps” makes them a well-suited medium for conveying complex scientific concepts to lay audiences and creating decision support tools that harness cutting edge modeling techniques and promote the work of environmental scientists and engineers. Despite this potential, the technical expertise required to develop web apps represents a formidable barrier—even for scientists and engineers who are skilled programmers. This paper describes four hurdles that contribute to this barrier and introduces an approach to overcoming these hurdles. We present an open source implementation of this approach, a development and hosting environment for environmental web apps called Tethys Platform. Several case studies are provided that demonstrates how the approach, as implemented within Tethys Platform, successfully lowers the barrier to web app development in the environmental domain.     

Experiences developing architectures for realizing thin‐client diagram editing tools

Diagram‐centric applications such as software design tools, project planning tools and business process modelling tools are usually ‘thick‐client’ applications running as stand‐alone desktop applications. There are several advantages to providing such design tools as Web‐based or even PDA‐ and mobile‐phone‐based applications. These include ease of access and upgrade, provision of collaborative work support and Web‐based integration with other applications. However, building such thin‐client diagram editing tools is very challenging. We have developed several thin‐client diagram editing applications realized as a set of plug‐in extensions to a meta‐tool for visual design environment development. In this paper, we discuss key user interaction and software architecture issues, illustrate examples of interacting with our thin‐client diagram editing tools, describe our design and implementation approaches, and present the results of several different evaluations of the resultant applications. Our experiences will be useful for those interested in developing their own thin‐client diagram editing architectures and applications. Copyright © 2007 John Wiley & Sons, Ltd.     

Voices of youth in reconceptualising and repositioning the role of mobile learning for sustainable development

ABSTRACT

This qualitative study explores youth’ perception of opportunities for mobile learning (M-Learning) as a means to achieve Sustainable Development Goals (SDGs). Data were collected through the qualitative case study of a M-Learning project called the 8th e-ICON World Contest hosted by Korean Ministry of Education and the Hawaii Department of Education. Drawing on youth’ insights and their knowledge as a basis for exploring the potential of M-Learning, the study recommends three areas for the integration of M-Learning with a view to achieving SDGs as follows: (1) M-Learning for improving access to education; (2) M-Learning for improving the quality of education; (3) M-Learning for building and scaling up collective partnership. The study also confirms that youth could play an active role in utilising opportunities of M-Learning to address the current educational development agenda and suggests how M-Learning can be conceptualized as a development intervention.     

A generic framework for constructing cross‐realm C2C‐PAKA protocols based on the smart card

A cross‐realm client‐to‐client password‐authenticated key agreement (C2C‐PAKA) protocol allows network clients from different realms managed by different servers to agree on a session key in an authentic manner based on easily memorizable passwords. In this paper, we present a generic framework for constructing a cross‐realm C2C‐PAKA protocol from any secure smart card‐based password authentication (PA‐SC) protocol. The security proof of our construction can be derived from the underlying PA‐SC protocol employing the same assumptions. Our generic framework appears to be the first one with provable security. In addition, compared with similar protocols, the instantiation of our construction achieves improved efficiency. Copyright © 2010 John Wiley & Sons, Ltd.     

Novel wide‐beam cross‐dipole CP antenna for GNSS applications

A wide‐beam circularly polarized (CP) cross‐dipole antenna for GNSS applications is proposed in this article. This cross‐dipole antenna is fed by a coaxial cable, on which the slots is added to optimize the impedance matching. These two pairs of dipole arms are designed with different lengths to obtain the circularly polarized radiation. Enhanced wide‐beam CP radiation characteristics can be achieved by curving the dipole arms and adjusting the distance between the arms and the metallic ground plane. The study of proposed antenna performance with different geometric parameters has been conducted. The final antenna exhibits a good impedance bandwidth (IBW) of ～13.1% (1.50‐1.71 GHz), and the 3‐dB axial‐ratio bandwidth is over 7% (1.52‐1.64 GHz). Broad pattern coverage of more than 140°, pure CP radiation at all designed bands and a wide 3 dB axial‐ratio beamwidth (ARBW) of nearly 150° makes this antenna an excellent candidate for satellite communications and navigation systems.     

基于HTML5的移动应用开发研究

随着科技的不断发展,智能化的移动设备被广泛应用,移动互联网在人们生活中扮演着越来越重要的角色。为了满足人们对智能移动设备的要求,适应不断发展的Web技术的应用需求,各种基于HTML5技术的移动应用大量涌现。本文首先从HTML5技术的新特征入手,介绍了移动应用开发的现状,进而分析HTML5在移动应用开发上的应用,最后将这种技术应用于中小学学习资源平台的建设和开发,指出了HTML5给移动学习和与开发者带来的新机遇与挑战。     

移动位置服务应用平台研究与开发

提出了一种移动位置服务的体系结构,开发、设计了其中的关键部件移动位置服务网关和位置服务应用平台,给出了实现位置服务的应用程序设计流程。经过实际测试表明,系统能够应用于移动通信网络为用户提供位置服务。     

Multi-task deep neural networks for just-in-time software defect prediction on mobile apps

With the development of smartphones, mobile applications play an irreplaceable role in our daily life, which characteristics often commit code changes to meet new requirements. This characteristic can introduce defects into the software. To provide immediate feedback to developers, previous researchers began to focus on just-in-time (JIT) software defect prediction techniques. JIT defect prediction aims to determine whether code commits will introduce defects into the software. It contains two scenarios, within-project JIT defect prediction and cross-project JIT defect prediction. Regardless of whether within-project JIT defect prediction or cross-project JIT defect prediction all need to have enough labeled data (within-project JIT defect prediction assumes that have plenty of labeled data from the same project, while cross-project JIT defect prediction assumes that have sufficient labeled data from source projects). However, in practice, both the source and target projects may only have limited labeled data. We propose the MTL-DNN method based on multi-task learning to solve this question. This method contains the data preprocessing layer, input layer, shared layers, task-specific layers, and output layer. Where the common features of multiple related tasks are learned by sharing layers, and the unique features of each task are learned by the task-specific layers. For verifying the effectiveness of the MTL-DNN approach, we evaluate our method on 15 Android mobile apps. The experimental results show that our method significantly outperforms the state-of-the-art single-task deep learning and classical machine learning methods. This result shows that the MTL-DNN method can effectively solve the problem of insufficient labeled training data for source and target projects.     

EPE‐Mobile—A framework for early performance estimation of mobile applications

Considering the constrained resources of mobile devices, a thorough performance evaluation of a mobile application is crucial. However, performance evaluation in the mobile domain is still a manual and time‐consuming task. The diversity of mobile devices only increases the complexity of this task. We propose EPE‐Mobile, a framework to automate early performance estimation in mobile applications. It is composed of a configurable library of basic operations and an engine that automatically creates a synthetic program based on the specification of a new app. The synthetic program that EPE‐Mobile generates provides feedback for mobile developers at the first design stages and before the actual implementation of a new application. The fast evaluation can also guide developers in optimizing their applications or in choosing devices with the best trade‐off between cost and performance to run a given application. Finally, developers can reuse the data collection infrastructure of the framework to collect performance data during all development stages. We validate the proposed framework using 4 applications from the Android Play Store. Based on their specifications, 4 synthetic programs were generated and executed on different devices. We compared the results to those obtained from the execution of the actual applications in the same devices. Experimental results show that it is possible to create synthetic applications with similar behavior to that of real applications and, thus, classify devices based on the actual application needs. The framework uses aspect‐oriented programming to collect the metrics of interest. This approach provides increased modularity and separation of concerns, thus facilitating the improvement of the framework itself, by adding other metrics or basic operations.     

3G移动互联网客户服务平台架构设计

随着各种智能手机的普及使用,传统的电话呼叫中心结合分布众多的营业厅模式已经无法满足3G移动手机用户多样化的服务需求。3G移动互联网客户服务平台将建立一个基于3G移动互联网的客户服务体系,通过3G移动互联网的方式向用户提供贴心服务,以文字、图片、演示视频、对讲、在线视频等服务方式远程指导、解答、协助解决用户在使用产品过程中遇到的实际困难和问题。     

Two‐parallax‐barriers‐based autostereoscopic liquid‐crystal display without cross‐talk

Abstract— An autostereoscopic liquid‐crystal display (LCD) consists of two parallax barriers and an LCD including a liquid‐crystal panel, and a backlight panel is proposed. Parallax barrier 1 is located between the backlight panel and the liquid‐crystal panel, and Parallax barrier 2 is located between the liquid‐crystal panel and viewers. The operation principle of the autostereoscopic display and the calculation equations for the parallax barriers are described in detail. The autostereoscopic LCD was developed and produces high‐quality stereoscopic images without cross‐talk at the optimal viewing distance and less cross‐talk than a conventional one based on one parallax barrier at other viewing distances.     

面向移动平台人脸检测的FaceYoLo算法

针对移动平台上人脸检测实时性不强的问题,提出了一种基于深度学习的FaceYoLo实时人脸检测算法。首先,在YoLov3检测算法的基础上,加入快速消化卷积层（RDCL）缩小输入空间,然后加入多尺度卷积层（MSCL）丰富不同检测尺度的感受野,最后加入中心损失和致密化策略加强模型的泛化能力和鲁棒性。实验结果表明,在GPU上测试时,该算法较YoLov3算法在速度上提高至原来的8倍,每幅图像的处理速度可达0.002 8 s;精度提高了2.1个百分点;在Android平台上测试时,该算法较最好的MobileNet模型在检测速率上从5 frame/s提升到10 frame/s。通过实验结果可知,该算法能有效提高人脸检测在移动平台上的实时性能。