关键词： 移动计算   电池续航时间预测   机器学习  

摘要： 如今,智能手机已成为人们日常生活中重要的组成部分.然而,在智能手机软硬件能力高速发展的同时,智能手机的电池能力却未能取得突破性的进展.这导致电池的续航能力经常会成为用户使用智能手机时的体验瓶颈.为了提高用户使用体验的优良感受,一种可行的方法是为用户提供电池续航时间预测.准确的电池续航时间预测能够帮助用户更加高效地规划其使用,从而能够改善其使用体验.由于缺乏高质量数据的支持,现有的电池续航时间预测方法通常比较简单,较难在真实场景下发挥实际用途.为了解决这一问题,基于一组细粒度大规模真实用户数据集,提出了一个智能手机电池续航时间预测模型.为了验证模型的效果,基于51名用户21个月内的细粒度使用数据进行了实验验证.结果显示:用户在发起查询时的使用行为、在当前会话内的使用行为以及其历史使用习惯上,均能够不同程度地帮助电池续航时间预测.总体来说,所提出的模型能够显著提升预测准确度.

关键词： Middleware   Sensors   Predictive models   Context modeling   Machine learning   Servers   Mobile applications   Anticipatory computing   mobile middleware   mobile sensing   prediction  

摘要： Ubiquitous computing is moving from context-awareness to context-prediction. In order to build truly anticipatory systems developers have to deal with many challenges, from multimodal sensing to modeling context from sensed data, and, when necessary, coordinating multiple predictive models across devices. Novel expressive programming interfaces and paradigms are needed for this new class of mobile and ubiquitous applications. In this paper we present FutureWare, a middleware for seamless development of mobile applications that rely on context prediction. FutureWare exposes an expressive API to lift the burden of mobile sensing, individual and group behavior modeling, and future context querying, from an application developer. We implement FutureWare as an Android library, and through a scenario-based testing and a demo app we show that it represents an efficient way of supporting anticipatory applications, reducing the necessary coding effort by two orders of magnitude.

关键词： smart cricket ball   performance analysis   mobile computing   skill performance   precession   gyroscope   spin rate   torque   wrist-spin   finger-spin   efficiency  

摘要： Introduction: Profiling of cricket bowlers is performed with motion analyses systems that require the placement of markers on the bowler's body and on the ball. Conventional smart balls such as cricket and baseballs provide only one speed and one spin rate datum at the release point, which is insufficient for biomechanical profiling. Method: In this study, we used an advanced smart cricket ball that measures the angular velocity at 815 Hz and calculates four further physical performance parameters (resultant torque, spin torque, power and angular acceleration) and five new skill parameters (precession, normalised precession, precession torque, efficiency and ratio of angular acceleration to spin rate), which we used for profiling and talent identification of spin bowlers. Results: The results showed that the spin rate is a function of physical (torque) and skill proficiency, namely how efficiently the torque is converted to angular velocity rather than being wasted for precession. The kind of delivery also influences the efficiency, as finger-spin deliveries were less efficient than wrist-spin ones by 6.8% on average;and topspin deliveries were generally more efficient than backspin ones by 15% on average. We tested three bowlers in terms of physical and skill performance during a 10-over spell, revealing that some parameters can improve or decline. When profiling a topspinner, we detected from the performance parameters a lower skill performance than expected, because there was an initial arm motion for backspin delivery before releasing the ball with a topspin. After training intervention, the skill parameters improved significantly (the efficiency increased from 39% to 59%). Conclusions: The advanced smart cricket ball is a classic example of mobile computing for sport performance analysis that can conducted indoors as well as outdoors, generating instant data from 10 performance parameters that provide critical feedback to the coach and bowler.

关键词： 创新体验   移动计算   云计算   三重价值   战略拓展   企业创新创业   微软   生产力  

摘要： 微软:要做中国企业创新创业的强劲引擎9月17日,荣耀与微软宣布深化战略合作,充分发挥双方在移动计算、云计算、个人计算及生产力应用等领域的优势技术与资源,携手打造全场景融合的创新体验,共同推动荣耀“1+8+N”战略拓展全球市场。对于荣耀而言,微软的助力可以带来三重价值:一是推动“1+8+N”战略,二是面向未来创新,三是拓展全球市场。

关键词： Self consistent field methods   Functions and functionals   Numerical linear algebra   Electronic correlation   Moller-Plesset perturbation theory   Fullerenes   Basis sets   Nuclear magnetic resonance   Mathematical crystallography   Coupled-cluster methods  

摘要： We report on a formulation and implementation of a scheme to compute nuclear magnetic resonance (NMR) shieldings at second-order Moller-Plesset (MP2) perturbation theory using gauge-including atomic orbitals (GIAOs) to ensure gauge-origin independence and Cholesky decomposition (CD) to handle unperturbed and perturbed two-electron integrals. We investigate the accuracy of the CD for the derivatives of the two-electron integrals with respect to an external magnetic field and for the computed NMR shieldings, before we illustrate the applicability of our CD-based GIAO-MP2 scheme in calculations involving up to about 100 atoms and more than 1000 basis functions.

关键词： 移动计算机   GPS定位技术   掌上电脑(PDA)  

摘要： 为了全面提升测绘工作的精准性,要结合移动计算平台应用要求,建立完整的控制方案,维持全球定位系统(Global Positioning System,GPS)定位技术的应用结构,发挥高精度、低成本的行业优势,为数据采集和应用管理效率的提升提供保障。本文简要分析基于掌上电脑(Personal Digital Assistant,PDA)的GPS信号接收和处理技术,并着重探讨了移动计算机平台下GPS定位技术的应用方案。

关键词： 移动计算   GPU   微架构   CPU架构   ARM   移动图形   发布会  

摘要： 在上一期的文章中,我们介绍了ARM Cortex-X2、Cortex-A710和Cortex-A510三款全新微架构,它们的出现进一步推高了移动计算CPU的性能上限。而在本次发布会上,除了新的CPU架构之外,ARM还发布了全新的GPU架构以及片上架构。在本文中,我们就来一起了解一下这些内容。

关键词： 群智感知   位置隐私   差分隐私   移动计算   城市计算  

摘要： 群智感知中,如何保护用户的地理位置隐私是核心问题之一。传统地理位置隐私保护方法通常需要对攻击者的先验知识进行假设,才能保证相应的保护效果。近期,一种新型的地理位置隐私保护机制,即"本地化差分隐私",被引入群智感知中,对用户的位置隐私进行保护。与传统方法相比,它能够在无需可信第三方的情况下,从理论上提供与攻击者先验知识无关的隐私保护效果。通过分析现有群智感知研究中与地理位置本地化差分隐私机制相关的工作,提出将地理位置本地化差分隐私机制融入不同群智感知应用的通用流程,并总结了流程中各个技术难点的可能解决方案。同时,指出了群智感知中地理位置本地化差分隐私机制相关研究的未来机遇,期望吸引更多的科研人员关注和投入这一研究方向。

关键词： 移动通信   移动终端  

ISBN: (纸本)9787115561268

摘要： 本书共两个部分，分别介绍移动计算理论和移动应用开发技术。在移动计算理论部分，主要介绍移动计算的基本概念、移动计算环境的要素、移动终端的发展、无线网络技术，以及无线定位技术。在移动应用开发技术部分，介绍基于Android操作系统的移动应用开发，主要包括界面开发、资源管理、数据存取、消息与服务、感知与多媒体，以及操作系统与通信。此外，本书还给出Android开发的命名规范，介绍常用的开发工具ADB和SQLite3。最后，本书还提供5个移动应用实验供读者练习。