Effectiveness Analysis of DVFS and DPM in Mobile Devices

The demand for high-performance embedded processors in multimedia mobile electronics is growing and their power consumption thus increasingly threatens battery lifetime.It is usually believed that the dynamic voltage and frequency scaling (DVFS) feature saves significant energy by changing the performance levels of processors to match the performance demands of applications on the fly.However,because the energy efficiency of embedded processors is rapidly improving,the effectiveness of DVFS is expected to change.In this paper,we analyze the benefit of DVFS in state-of-the-art mobile embedded platforms in comparison to those in servers or PCs.To obtain a clearer view of the relationship between power and performance,we develop a measurement methodology that can synchronize time series for power consumption with those for processor utilization.The results show that DVFS hardly improves the energy efficiency of mobile multimedia electronics,and can even significantly worsen energy efficiency and performance in some cases.According to this observation,we suggest that power management for mobile electronics should concentrate on adaptive and intelligent power management for peripheral devices.As a preliminary design,we implement an adaptive network interface card (NIC) speed control that reduces power consumption by 10% when NIC is not heavily used.Our results provide valuable insights into the design of power management schemes for future mobile embedded systems.     

An OSGi-based flexible and adaptive pervasive cloud infrastructure

There is a trend that different computing paradigms such as cloud computing, pervasive, and mobile computing are converging with each other. Due to this convergence, there arise unprecedented complexities, such as huge number of computing devices, flexibilities and adaptation of service infrastructure （infrastructure elasticity） for fitting dynamics of large smart city applications, expectations of powerful computing and storage capabilities on handhold devices, and so on. Therefore, a supporting infrastructure is needed, which can flexibly switch services at run time and can be used to enhance capabilities for small devices through component/service migrations. In this paper, we propose an elastic open service gateway initiative （OSGi）-based pervasive cloud （OSGi-PC） infrastructure which can make use of both the cloud computing capabilities and the component flexibilities from OSCi. OSGi-PC provides flexible management of component migrations between small devices themselves and powerful nodes in between, which is remaining a critical challenge for enabling mobile clouds. We have evaluated the OSGi-PC in terms of performance for adaptive service provision, and power consumption during service adaptation, performance and power consumption for component migrations in different scenarios, which show the usability of OSGi-PC.     

Employing computational intelligence to generate more intelligent and energy efficient living spaces

Our living environments are being gradually occupied with an abundant number of digital objects that have networking and computing capabilities. After these devices are plugged into a network, they initially advertise their presence and capabilities in the form of services so that they can be discovered and, if desired, exploited by the user or other networked devices. With the increasing number of these devices attached to the network, the complexity to configure and control them increases, which may lead to major processing and communication overhead. Hence, the devices are no longer expected to just act as primitive stand-alone appliances that only provide the facilities and services to the user they are designed for, but also offer complex services that emerge from unique combinations of devices. This creates the necessity for these devices to be equipped with some sort of intelligence and self-awareness to enable them to be self-configuring and self-programming. However, with this ＂smart evolution＂, the cognitive load to configure and control such spaces becomes immense. One way to relieve this load is by employing artificial intelligence （AI） techniques to create an intelligent ＂presence＂ where the system will be able to recognize the users and autonomously program the environment to be energy efficient and responsive to the user＇s needs and behaviours. These AI mechanisms should be embedded in the user＇s environments and should operate in a non-intrusive manner. This paper will show how computational intelligence （CI）, which is an emerging domain of AI, could be employed and embedded in our living spaces to help such environments to be more energy efficient, intelligent, adaptive and convenient to the users.     

SeaHttp: A Resource-Oriented Protocol to Extend REST Style for Web of Things

Web of Things （WoT） makes it possible to connect tremendous embedded devices to web in Representational State Transfer （REST） style. Some lightweight RESTful protocols have been proposed for the WoT to replace the HTTP protocol running on embedded devices. However, they keep the principal characteristic of the REST style. In particular, they support one-to-one requests in the client-server mode by four standard RESTful methods （GET, PUT, POST, and DELETE）. This characteristic is however inconsistent with the practical networks of embedded devices, which typically perform a group operation. In order to meet the requirement of group communication in the WoT, we propose a resource-oriented protocol called SeaHttp to extend the REST style by introducing two new methods, namely BRANCH and COMBINE respectively. SeaHttp supports parallel processing of group requests by means of splitting and merging them. In addition SeaHttp adds spatiotemporal attributes to the standard URI for naming a dynamic request group of physical resource. Experimental results show that SeaHttp can reduce average energy consumption of group communication in the WoT by 18.5%, compared with the Constrained Application Protocol （CoAP）.     

Bitstream decoding and SEU-induced failure analysis in SRAM-based FPGAs

Reconfigurable SRAM-based FPGAs are highly susceptible to radiation induced single-event upsets (SEUs) in space applications.The bit flip in FPGAs configuration memory may alter user circuit permanently without proper bitstream reparation,which is a completely different phenomenon from upsets in traditional memory devices.It is important to find the relationship between a programmable resource and corresponding control bit in order to understand the impact of this effect.In this paper,a method is proposed to decode the bitstream of FPGAs from Xilinx Corporation,and then an analysis program is developed to parse the netlist of a specific design to get the configuration state of occupied programmable logic and routings.After that,an SEU propagation rule is established according to the resource type to identify critical logic nodes and paths,which could destroy the circuit topological structure.The decoded relationship is stored in a database.The database is queried to get the sensitive bits of a specific design.The result can be used to represent the vulnerability of the system and predict the on orbit system failure rate.The analysis tool was validated through fault injection and accelerator irradiation experiment.     

A Privacy Taxonomy for the Management of Ubiquitous Environments

Pervasive and ubiquitous environments must handle the detection and management of users, devices and services, while guaranteeing the privacy of both the users and the environment itself. Current techniques for handling privacy found in the literature treating the subject in various ways, while concentrating on the device management, communication protocols, user profiles and environmental access. This paper examines a control model for privacy in pervasive environments from the perspective of the environment. A prototype was devised and tested to validate the generic model of privacy which was also used to compare taxonomic concepts in the literature. Moreover, the prototype was devised and tested to validate the generic model of privacy for control and manage various users, devices and environments and so on. The prototype was based on Percontrol （a system for pervasive user management）, which was only intended to identify users using Wi-Fi, and now it is capable of managing temperature, luminosity and other preferences, measured by a WSN （wireless sensor network） embedded to Percontrol, and the data treatment is done by an ANN （artificial neural network）. Results confirmed the viability of device detection with Wi-Fi, Bluetooth and RFID （radio frequency identification） for an increases slight of the latency in registering new devices on the system.     

Real-time manifold regularized context-aware correlation tracking

Despite the demonstrated success of numerous correlation filter(CF)based tracking approaches,their assumption of circulant structure of samples introduces significant redundancy to learn an effective classifier.In this paper,we develop a fast manifold regularized context-aware correlation tracking algorithm that mines the local manifold structure information of different types of samples.First,different from the traditional CF based tracking that only uses one base sample,we employ a set of contextual samples near to the base sample,and impose a manifold structure assumption on them.Afterwards,to take into account the manifold structure among these samples,we introduce a linear graph Laplacian regularized term into the objective of CF learning.Fortunately,the optimization can be efficiently solved in a closed form with fast Fourier transforms(FFTs),which contributes to a highly efficient implementation.Extensive evaluations on the OTB100 and VOT2016 datasets demonstrate that the proposed tracker performs favorably against several state-of-the-art algorithms in terms of accuracy and robustness.Especially,our tracker is able to run in real-time with 28 fps on a single CPU.     

A Chain Datatype in Z

We present results about a general-purpose chain datatype specified in the Z notation and mechanised using the Z/Eves theorem prover. Our particular interest comes from its use in the specification and refinement of operating system kernels for embedded real-time devices as part of a pilot project within the international Grand Challenge in Verified Software, and to contribute to the Verified Software Repository. We show—at afairly high level—the sort of dogged work that is needed to get a body of results together to form a basis for future projects. Our work discusses important hidden and missing properties in the specification of the chain datatype and its relation to kernel design.     

Design of Objects Tracking System Based on ARM Embedded Platform

In recent years, according to the need of intelligent video surveillance system increasing rapidly in metropolitan cities ,a design based on $3C2440 microprocessor and embedded Linux operating system is adopted for real-time video target tracking. However, it is very challenging as embedded systems usually afford limited processing power and limited resources. Therefore, to address this problem, a real-time tracking algorithm using multi-features based on compressive sensing is proposed and implemented The algorithm uses multiple matrix as the projection matrix of the compressive sensing and the compressed date as the multiple features to extract useful information needed by tracking process. Functions and libraries in OpenCV which were developed by Intel Corporation are utilized for building the tracking algorithms. It is tested with variant video sequences and the results show that the algorithm achieves stable tracking for the target moved of the light changed.     

Improvements to the Control Techniques of Sequential Inference Machines——from Instructions to Hardware Organization

Nondeterminism of PROLOG execution requires that a block of control information or a choicepoint for each procedure call be stored when there are other candidate clauses to be used.Whenthe currently selected clause fails,the bindings made by the clause must be undone and the storedchoice point is reactivated,and then another clause of the candidate ones is chosen to run on it.Storing and reactivating choice points and undoing account for the great overhead are required tocontrol PROLOG execution,which is quite different from conventional programs.This paper focuses on the techniques used in Sequential PROLOG Engine(SPE)to reduce theoverhead of control operations.The control instructions of SPE store no more choice points thanthe necessary.Its architecture takes the approaches of analysing the potential parallelism in the con-trol operations and developing a fraction of it due to the cost-effect consideration.The results ofexecuting two sample programs on SPE in the form of hand timings are presented,which favor theapproach.     

Linux平台下支持触摸屏的Qt／Embedded移植

随着嵌入式的发展,触摸屏以友善的人机交互性、操作简单灵活、输入速度快,已逐渐取代键盘,成为嵌入式系统的主流输入设备;而Qt作为跨平台的图形用户界面工具包诞生以后,已经扩展到了包括便携式设备在内的几乎当今程序设计的所有领域。以S3C2416为例,介绍了在Linux平台下支持触摸屏的Qt／Embedded移植的详细过程,包括系统环境介绍、带触摸屏库的Qt／Embedded的编译、Linux文件系统设置等,并挑选了一个demo程序对移植情况进行了检验。最后对支持触摸屏的嵌入式系统作了初步展望。     

基于Linux的嵌入式GUI系统设计分析

随着技术的发展,嵌入式系统要求使用图形化界面便于用户的操作。本文从系统体系结构出发,讨论了GUI设计中涉及的几个重要方面,包括消息循环、多窗口管理、控件／控件类和输入／输出抽象层的基本概念和设计要点。     

基于Qt／Embedded的GUI应用程序的实现

随着当前各种手持设备、无线设备及信息家电等嵌入式产品的迅猛发展,相应的嵌入式软硬件设计技术也在发生深刻的变化。如今越来越多的嵌入式终端需要一个图形化的人机接口面,GUI应用程序的设计是嵌入式系统设计的一个关键技术,能极大地提高人机交互的效率。介绍了嵌入式LinuxGUI的发展概况,描述了Qt／Embedded的开发环境,并结合实例阐述了基于QT／Embedded的GUI应用程序的开发过程以及如何将应用程序添加到Qtopia。     

基于Qt/E嵌入式GUI设计的研究与实现

随着嵌入式系统在信息家电、移动通信、手持设备以及工业控制等众多领域的广泛应用,Qt便携式电子设备应用程序的开发正日益成为嵌入式GUI开发的主流。本文介绍了Qt/E的基本模型及Qtopia应用平台的基本概况,基于Qt/E的嵌入式GUI开发环境的搭建,并结合X86和开发板阐述了基于Qt/E的嵌入式GUI设计及实现方法。     

基于Qt/Embedded的嵌入式GUI的研究与构建

嵌入式系统在手机、PDA等手持信息设备领域的应用出现了强劲的发展势头。而一个十分友好的图形用户界面(GUI)是嵌入式系统设计的关键技术之一,针对这种GUI的开发应用软件有很多,Qt/E是其中比较流行的一种。首先分析了Qt/E的运行机制及特点,并详细阐述其在基于ARM的嵌入式Linux系统下的移植方法,最后使用一个简单的应用程序来说明Qt/Embedded的嵌入式GUI的开发流程。     

基于Linux的中低端嵌入式GUI的开发

本文介绍了Linux下嵌入式GUI的发展及其在系统中的作用，研究了嵌入式GUI的设计思想，着重阐述了如何在中低端设备上实现windows风格的多进程多窗口剪切，提出了如何借助Z序和树型结构实现多窗口的管理，最后分析了所设计的GUI特点。     

基于嵌入式Linux系统的掌上Emap的设计

本文对基于嵌入式Linux系统下不同的图形用户界面(GUI)进行了综合的介绍和比较,并根据Emap的工作原理,提出了在嵌入式Linux系统下的掌上PDA上运行Emap的一种实现模型,具有较强的实用价值。     

SkyEye模拟器的LCD及TouchScreen模拟模块的设计、实现与验证

本文首先描述了开放源码的嵌入或硬件仿真环境SkyEye的总体架构,然后对SkyEye模拟器的LCD及TouchScreen模拟模块的设计、实现与验证过程进行了深入的阐述,并且分析比较了LCD模拟的不同实现方式。开源嵌入式GUI系统—MiniGUI和Linux 操作系统在SkyEye 模拟器上的成功运行说明了SkyEye 模拟器的LCD及TouchScreen模拟模块的设计实现是正确和可靠的。     

基于QT/E的嵌入式图形支持系统

面向消费电子的嵌入式技术迅速发展，对图形支持系统提出了更高的要求。该文给出了一种资源受限系统的轻型高效的嵌入式图形系统解决方案，结合数字电视应用的具体需求，阐述了该系统的体系结构、移植技术和实现方法。该图形支持系统已经成功运行于目标平台，证明了技术方案是可行有效的。 关键词：     

KVM在基于构件的嵌入式操作系统上的移植和研究

新信息家电时代的到来,嵌入式操作系统已经发挥了重要的作用,目的就是在资源有限的移动设备和家电产品上提供给用户稳定而丰富的使用功能。特别在目前手机移动开发上,Java技术提供给用户多种应用服务,所以发展空间比较大。介绍在中国自主知识产权的基于CAR构件技术的智能手机操作系统ElaME (Elastos Mobile Edition)上,嵌入式Java虚拟机的移植和研究,考虑如何实现KVM的本地接口和图形界面等。