Energy-efficient mobile web in a bundle

The mobile Internet that was a huge hype ten years ago is finally here. We have a wealth of mobile devices that allow us to enjoy and consume Internet content from any number of web sites and services. With faster processors and radio links, our use of the Internet and the traffic mobile users generate grows at a tremendous pace. In this development, we still have a huge challenge to tackle: energy efficiency. When ten years ago one would recharge his personal mobile device once a week, we now do that daily; Smart phones today are not able to carry enough energy to allow us several days of usage time. The focus on this paper is to present and analyse one solution to help us in our daily lives. We implement and study a scheme where web content, a page, is delivered as a whole to a mobile device, instead of sending each individual object of the page separately. Combined with RRC state based header compression and selective content compression, our proposal allows the radio to keep in low power state for longer durations, and as a consequence brings huge energy savings. Download times also decrease, thus bringing increased Quality of Experience.     

Advanced mobile and wearable systems

The recent spectacular progress in the microelectronic, information, communication, material and sensor technologies created a big stimulus towards development of smart communicating cyber-physical systems (CPS) and Internet of Things (IoT). CPS and IoT are undergoing an explosive growth to a large degree related to advanced mobile systems like smart automotive and avionic systems, mobile robots and wearable devices. The huge and rapidly developing markets of sophisticated mobile cyber-physical systems represent great opportunities, but these opportunities come with a price of unusual system complexity, as well as, stringent and difficult to satisfy requirements of many modern applications. Specifically, smart cars and various wearable systems to a growing degree involve big instant data from multiple complex sensors or other systems, and are required to provide continuous autonomous service in a long time. In consequence, they demand a guaranteed (ultra-)high performance and/or (ultra-)low energy consumption, while requiring a high reliability, safety and security. To adequately address these demands, sophisticated embedded computing and embedded design technologies are needed. After an introduction to modern mobile systems, this paper discusses the huge heterogeneous area of these systems, and considers serious issues and challenges in their design. Subsequently, it discusses the embedded computing and design technologies needed to adequately address the issues and overcome the challenges in order to satisfy the stringent requirements of the modern mobile systems.     

Program-based dynamic precision selection framework with a dual-mode unified shader for mobile GPUs

To extend the life of battery-driven mobile devices while maintaining image quality, this work proposes a Program-based Dynamic Precision Selection (PDPS) framework with a dual-mode unified shader. Since fixed-point arithmetic can be performed faster and more energy-efficiently than floating-point arithmetic on power-limited devices, the use of fixed-point rather than floating-point rendering is a critical concern. The proposed PDPS framework is composed of a runtime profile-based mechanism for automatically determining the precision of each shading program in fixed-point arithmetic. Additionally, a scene change detection mechanism is developed to recalculate the rendering precision whenever a 3D scene changes. The results reveal an average 18% reduction in energy and 35% faster performance under fixed-point rendering. The degradation in rendered image quality under the proposed PDPS cannot be detected by the naked eye, and the PSNR is an average of 15% better than that achieved using related approach.     

Energy-efficient localization and target tracking via underwater mobile sensor networks

Underwater mobile sensor networks (UMSNs) with free-floating sensors are more suitable for understanding the immense underwater environment. Target tracking, whose performance depends on sensor localization accuracy, is one of the broad applications of UMSNs. However, in UMSNs, sensors move with environmental forces, so their positions change continuously, which poses a challenge on the accuracy of sensor localization and target tracking. We propose a high-accuracy localization with mobility prediction (HLMP) algorithm to acquire relatively accurate sensor location estimates. The HLMP algorithm exploits sensor mobility characteristics and the multi-step Levinson-Durbin algorithm to predict future positions. Furthermore, we present a simultaneous localization and target tracking (SLAT) algorithm to update sensor locations based on measurements during the process of target tracking. Simulation results demonstrate that the HLMP algorithm can improve localization accuracy significantly with low energy consumption and that the SLAT algorithm can further decrease the sensor localization error. In addition, results prove that a better localization accuracy will synchronously improve the target tracking performance.     

一种简单无线供电车灯装置的设计

随着科学技术的日益发展,汽车制造行业也逐渐成熟,对于汽车中供电车灯的关注度正在逐步提高,而非接触供电车灯的研究是汽车制造业更为关注的课题。本文对非接触供电车灯的原理以及设计作了较为详细的阐释,并用ARM微处理器作为非接触供电车灯的无线反馈稳压电路的处理单元,利用Protel DXP2004设计出原边和副边的PCB板,采用编程工具Keil u Vison4编写原边电路的发射程序。最后对于这种车灯的性能做出了分析,并预测其将成为汽车行业发展的一种前景。     

Application design for wearable and context-aware computers

To effectively integrate wearable computers into ubiquitous computing environments, we must address several important challenges. How do we develop social and cognitive application models? How do we integrate input from multiple sensors and map them to users' social and cognitive states? How do we anticipate user needs? How do we interact with users? To address mobile-application design challenges, the authors created four user interface models that map problem-solving capabilities to application requirements.     

Improving the efficiency and reliability of wearable based mobile eHealth applications

In this paper we address the support of wearable mHealth applications in LTE and future 5G networks following a holistic approach that spans across the elements of a mobile network. The communication requirements change from one application to another so we propose a measurement methodology to facilitate the selection of the user equipment to fulfil these requirements. We also discuss a new network architecture to support traffic prioritization, RAN programmability, low latency and group communications to over-the-top applications. Our proposal is validated using several realistic experimentation platforms and the results show that mHealth systems can benefit from our approach.     

一种可穿戴式近红外光谱成像系统的前端设计

提出了一种连续波多通道可穿戴式功能近红外光谱成像系统的前端设计,用于实时同步监测脑功能活动。在该系统中,选择性能良好驱动简单的双波长LED作为光源,光源驱动电路采用可编程集成芯片,实现光源调制及时分复用,有效区分来自不同通道的信号,同时也去除了环境光等背景噪声的干扰。并利用光电二极管、ADS1299和GS1011完成信号的采集处理以及传输,实现一款低功耗、高精度、无线传输的功能近红外光谱成像系统前端。     

Human-centered design of a wearable kinesthetic haptic device for surgical teleoperation

Artificial Life and Robotics - This paper describes the design and performance evaluation of a flexible wearable haptic device that aims to realize full kinesthetic haptic feedback for application...     

Issues in the design and use of wearable computers

Wearable computers are fully functional, self-powered, self-contained computers that allow the user to access information anywhere and at any time. In this paper, design issues for wearable computers are discussed, including power considerations, use of input devices, image registration, and the use of wearable computers for the design of smart spaces. Application areas for wearable computers are presented, including medicine, manufacturing, maintenance, and as personal assistants. Finally, future research directions for wearable computers are indicated.     

Interaction on-the-go: a fine-grained exploration on wearable PROCAM interfaces and gestures in mobile situations

Wearable projector and camera (PROCAM) interfaces, which provide a natural, intuitive and spatial experience, have been studied for many years. However, existing hand input research into such systems revolved around investigations into stable settings such as sitting or standing, not fully satisfying interaction requirements in sophisticated real life, especially when people are moving. Besides, increasingly more mobile phone users use their phones while walking. As a mobile computing device, the wearable PROCAM system should allow for the fact that mobility could influence usability and user experience. This paper proposes a wearable PROCAM system, with which the user can interact by inputting with finger gestures like the hover gesture and the pinch gesture on projected surfaces. A lab-based evaluation was organized, which mainly compared two gestures (the pinch gesture and the hover gesture) in three situations (sitting, standing and walking) to find out: (1) How and to what degree does mobility influence different gesture inputs? Are there any significant differences between gesture inputs in different settings? (2) What reasons cause these differences? (3) What do people think about the configuration in such systems and to what extent does the manual focus impact such interactions? From qualitative and quantitative points of view, the main findings imply that mobility impacts gesture interactions in varying degrees. The pinch gesture undergoes less influence than the hover gesture in mobile settings. Both gestures were impacted more in walking state than in sitting and standing states by all four negative factors (lack of coordination, jittering hand effect, tired forearms and extra attention paid). Manual focus influenced mobile projection interaction. Based on the findings, implications are discussed for the design of a mobile projection interface with gestures.     

校正数据库模式在手机定位系统中的实现

介绍一种基于Windows Mobile操作系统的手机定位系统解决方案,其中GPS适用在障碍物较少的区域,基站定位作为位置信息采集的有力补充,同时采用校正数据库的模式来实现经纬度校正。本方案能有效纠正手机定位中的地图偏移,提高信号的稳定性,保障定位精度,并且没有额外增加手机的制造成本。     

无线供能移动边缘计算系统的安全卸载优化

针对能量受限的多用户移动边缘计算（MEC）系统存在恶意窃听节点的问题,提出一种联合无线能量传输（WPT）和MEC的安全部分计算卸载方案。该方法以系统接入点（AP）能耗最小化为优化目标,在计算延迟、安全卸载和能量捕获约束条件下,联合优化AP能量传输协方差矩阵、本地CPU频率、用户卸载比特数、用户卸载时间分配以及用户传输功率。针对AP能耗最小化问题为非凸问题,首先采用凸差分算法（DCA）将原始非凸问题转换为凸问题,然后采用拉格朗日对偶法以半封闭形式获得问题最优解。当计算任务数为5×10⁵比特时,与本地计算和安全全部计算卸载方法相比,安全部分卸载方案的能量消耗分别降低了61.3%和84.4%;当窃听节点距离超过25 m时,安全部分卸载方案所消耗的能量远小于本地计算和安全全部计算卸载。仿真实验结果表明,在保证物理层安全卸载的情况下,所提方案能够有效降低AP能耗、提高系统性能增益。     

The autonomous mobile robot SENARIO: a sensor aided intelligentnavigation system for powered wheelchairs

The SENARIO project is develoing a sensor-aided intelligent navigation system that provides high-level navigational aid to users of powered wheelchairs. The authors discuss new and improved technologies developed within SENARIO concerning task/path planning, sensing and positioning for indoor mobile robots as well as user interface issues. The autonomous mobile robot SENARIO, supports semi- or fully autonomous navigation. In semi-autonomous mode the system accepts typical motion commands through a voice-activated or standard joystick interface and supports robot motion with obstacle/collision avoidance features. Fully autonomous mode is a superset of semi-autonomous mode with the additional ability to execute autonomously high-level go-to-goal commands. At its current stage, the project has succeeded in fully supporting semi-autonomous navigation, while experiments on the fully autonomous mode are very encouraging     

可穿戴式的功能近红外光谱成像系统的前端设计

针对脑部血氧非侵入式无损血氧检测,设计了一款多通道的可穿戴式功能近红外光谱成像系统的前端。采用超低功耗无线片上系统(System on a Chip,So C)芯片作为控制中心以及无线传送模块,借用时分复用技术实现光源驱动,利用高灵敏度的光电传感器以及高分辨率的模数转换芯片实现信号采集,实现一款体积小、功耗低、精度高、无线数传、可实时检测脑部血氧浓度的系统前端。给出了光源驱动与信号采集扩展方案,使得系统可以自由配置成更多通道采集系统。     

基于ZigBee的可穿戴心电监护系统设计

提出了一种可穿戴式心电医疗监护系统设计方案,该方案利用ZigBee技术将若干可穿戴心电检测终端根据需求构建相应结构的无线传感器网络,由服务主机完成数据汇总、存储、显示等一系列信息化管理功能。无线传感器网络节点主要由心电监测芯片BMD101、STC微处理器和CC2530无线收发模块等构成。设计作品结果表明,该方案可行,并获得第十四届广东省电子设计大赛三等奖。     

一种新的移动Agent保护方案研究与设计

随着移动Agent技术在分布式计算中的应用,移动Agent系统在安全和软件工程两方面面临着巨大的挑战。为了防止恶意或未授权的第三方实体的攻击,研究了保护移动Agent数据和代码的方法。设计了一种全新的移动Agent结构,由封装了所有要在特定主机平台上执行的代码的数据和负责传送并处理这些数据的显示代码构成,这种数据代码分离结构与其他已有的移动Agent结构互不影响,因而提高了移动Agent平台之间的互操作性。同时描述了公钥解密和Agent验证机制,实现了保护数据免受篡改代码引起的攻击,以及通过进一步改进数据的结构,实现了保护代码免受注入恶意数据引起的攻击。     

Fitts’ 模型在移动与可穿戴计算交互中的可用性研究*

近年来移动计算与可穿戴计算范式已进入高速发展期,此类计算范式通常采用基于手持小屏幕与头戴显示器的受限视场显示技术以及基于多点触摸的指点输入技术。然而此类受限视场显示设备将引起交互过程中的变视场及微目标问题,这些问题可能又将导致人机交互绩效的显著变化,进而影响其交互绩效的传统研究工具——Fitts’模型的可用性。通过人机交互实验,分别针对变视场条件及微目标条件对基于指点交互的人机绩效进行了定量分析,并基于此对Fitts’模型在移动与可穿戴计算中的可用性进行了研究。结果表明传统 Fitts’模型不能适用于显示     

Energy-efficient mobile target detection in Wireless Sensor Networks with random node deployment and partial coverage

This paper addresses the problem of engineering energy-efficient target detection applications, using unattended Wireless Sensor Networks (WSNs) with random node deployment and partial coverage, for long-lasting surveillance of areas of interest. As battery energy depletion is a crucial issue, an effective approach consists in switching on and off, according to proper duty cycles, sensing and communication modules of wireless sensor nodes. Making these modules work in an intermittent fashion has an impact on (i) the latency of notification transmission (depending on the communication duty cycle), (ii) the probability of missed target detection (depending on the number of deployed nodes, the sensing duty cycle, and the number of incoming targets), and (iii) the delay in detecting an incoming target. In order to optimize the system parameters to reach given performance objectives, we first derive an analytical framework which allows us to evaluate the probability of missed target detection (in the presence of either single or multiple incoming targets), the notification transmission latency, the detection delay, and the network lifetime. Then, we show how this “toolbox” can be used to optimally configure system parameters under realistic performance constraints.