An Adaptive Location Detection scheme for energy-efficiency of smartphones

Global Positioning System (GPS) is widely used for the Location-Based Service (LBS) of smartphones. However, GPS dramatically increases the power consumption of a smartphone due to heavy computation overhead. Cell-tower Based Localization (CBL) can be an alternative solution to perform LBS in an energy-efficient way; but its adoption is limited due to the low positioning accuracy. This paper presents a new location estimation scheme for smartphones called Adaptive Location Detection (ALD). ALD adaptively detects the location of a smartphone considering the category of applications executed, movement pattern of a user, and the battery level. Specifically, ALD categorizes applications according to the required level of positioning accuracy, and then adaptively utilizes GPS and CBL. ALD also takes different actions according to the movement pattern of a user and the remaining battery level of the smartphone. To assess the effectiveness of the proposed scheme, we perform simulations under five location based applications and six scenarios. The evaluation results show that ALD reduces the energy consumption of GPS by 49.5% on average. Nevertheless, it satisfies the accuracy requirement of each situation.     

Kernelized correlation tracker on smartphones

This paper shows the implementation of a KC tracker (high-speed kernelized correlation tracker) on an Android smartphone. The image processing part is implemented with the Android-NDK in C/C++. Some parts of the tracking algorithm, which can be parallelized very well, are partitioned and calculated on the GPU with OpenGL ES and OpenCL. Other parts, such as the Discrete Fourier Transform (DFT), are calculated on the CPU (partly with the ARM-NEON features). With these hardware acceleration steps we could reach real-time performance (at least 20–30 FPS) on up-to-date smartphones, such as Samsung Galaxy S4, S5 or Google Nexus 5.Beyond that, we present some new color features and compare their tracking quality to the HOG features using the KC tracker and show that their tracking quality is mostly superior compared to the HOG features.If an object gets lost by the tracker which is the case e.g. if the object is totally hidden or outside the viewing range, there should be a possibility to perform a re-detection. In this paper, we show a basic approach to determine the tracking quality and search for the tracking object in the entire images of the subsequent video-frames.     

State of the art and future developments of the Augmented Reality for measurement applications

Augmented Reality (AR) is a technology that enriches the sensorial perception of a person by adding virtual contents directly on the user’s surrounding environment. The modern AR platforms, such as smartphones and head-mounted displays, are moving the application fields of this technology from research centers to a wide range of application domains. The aims of the paper are to highlight the role of measurements in an AR system and the AR as support to the measurements. In the first part, the evolution of AR concept and platforms that can implement AR systems, are presented. An AR system requires measurements of user and objects position and orientation, for this reason, several tracking systems and some calibration procedures are described. A survey of applications using the AR as user interface of measurement system is presented. Furthermore, future trends for researches oriented on the development of calibration procedures for tracking systems are discussed.     

An Exploratory Research on the Correlation Between Screen Time and Walking

With the revolution of information technology greatly changing contemporary’s lifestyle, smartphone becomes a necessity to more and more people, and individuals’ screen time is increasing as people are spending more time on the virtual world. Through literature review, this paper proposes a hypothesis that there is a correlation between smartphone screen time and walking step counts, which is verified through an exploratory research: data of walking step counts and screen usage were widely collected by online and onsite questionnaires, and the analyses reveal that 1) when daily screen time ranges from 4.99 to 15.25 hours, it is negatively correlated with daily walking step counts; 2) the respondents’ average daily screen time is 6.3 hours, more of which (2.8 hours) is spent on social Apps, and their average daily walking step counts are 6,750 (takes nearly 0.8 hour); 3) daily screen time and walking step counts at weekends are less than those on weekdays; 4) people with higher education level, higher income, or younger age use screen less daily; people with higher education level, lower exercise frequency, or younger age walk less daily, so these factors are likely to affect the correlation between daily screen time and daily walking step counts. The correlation of both behaviors and the affecting factors need to be further clarified, and the impact of physical environmental elements on walking also requires more attention.     

College students' cell phone use and attachment to parents and peers

College students spend hours each day using their cell phones. A common motivation for this behavior is the maintenance of social relations. Yet depending on cell phone use behavior, cell phone use could potentially strengthen or weaken social relations. We investigated this possibility with a survey (N = 493) assessing students' perceptions of important social relations (i.e., Inventory of Parent and Peer Attachment) and various cell phone use behaviors. The relationship between cell phone use and Parent Attachment was modeled with three regression equations, one for each Parent Attachment subscale (i.e., communication, trust, alienation). These subscales were the criterion variables. Each regression equation contained the same predictor variables: total daily cell phone use, calling, texting, and problematic use. Anxiety and self-esteem were control variables. The relationship between cell phone use and Peer Attachment was modeled similarly. Regression equations were estimated simultaneously using the Seemingly Unrelated Regression technique. For males: calling, texting and total daily use were not related to parent or peer attachment; problematic use was negatively related to parent and peer attachment. For females: calling was positively related to parental attachment and texting to peer attachment; problematic use was negatively related to parent and peer attachment. Implications are discussed.     

A vicious circle between children’s non-communicative smartphone use and loneliness: Parents cannot do much about it

Children are increasingly using their own smartphones for communicative and non-communicative purposes. In fact, studies showed that different ways of using the smartphone might influence loneliness, and as a consequence, loneliness might also enhance further engagement with the smartphone. In this context, parents play an important role because they can regulate children’s smartphone use. The present study tested the moderating role of active and restrictive parental mediation on the relations between different types of smartphone use and children’s loneliness. We conducted a two-wave panel survey among 10- to 14-year-old children and their parents, resulting in total of 384 parent–child pairs at Time 2. Our results revealed that non-communicative use at Time 1 increased loneliness at Time 2. We also found a reciprocal influence, that is, loneliness at Time 1 increased children’s non-communicative use at Time 2. We found no moderating influence of active and restrictive parental mediation on the relations between children’s smartphone use and loneliness. Our findings are discussed against the background of the poor-get-poorer effect regarding smartphone use.     

Decoupling data-at-rest encryption and smartphone locking with wearable devices

Smartphones store sensitive and confidential data, e.g., business related documents or emails. If a smartphone is stolen, such data are at risk of disclosure. To mitigate this risk, modern smartphones allow users to enable data encryption, which uses a locking password to protect the data encryption key. Unfortunately, users either do not lock their devices at all, due to usability issues, or use weak and easy to guess 4-digit PINs. This makes the current approach of protecting confidential data-at-rest ineffective against password guessing attackers. To address this problem we design, implement and evaluate the Sidekick system — a system that uses a wearable device to decouple data encryption and smartphone locking. Evaluation of the Sidekick system revealed that the proposal can run on an 8-bit System-on-Chip, uses only 4 Kb/20 Kb of RAM/ROM, allows data encryption key fetching in less than two seconds, while lasting for more than a year on a single coin-cell battery.     

Power management techniques in smartphone-based mobility sensing systems: A survey

The rapidly enhancing sensing capabilities of smartphones are enabling the development of a wide range of innovative mobile sensing applications that are impacting on everyday life of mobile users. However, supporting long-term sensing applications is challenging because of their key requirements for continuous access to embedded sensors for gathering raw data, which can deplete the device’s battery in a few hours. This problem is expected to remain in the near future because the improvements on the capacity of batteries are coming at a slower pace than those advances in computing and sensing capabilities. The research community has highlighted the need for power-aware and context-aware sensing techniques deployed at different levels of mobile platforms for making a more efficient use of energy resources. Previous studies have analyzed the optimization of power consumption in mobile devices over different critical axes, like data transmission, computing, and hardware design. However, a comprehensive study focused in the challenges of power-aware smartphone-based sensing and strategies for addressing them has not been produced yet. This survey aims to fill this void with a particular focus on mobility sensing systems (e.g., human activity recognition, location-based services), presenting a comprehensive review of relevant strategies aimed at solving this issue. Also, this survey defines a taxonomy for such solutions, highlighting their strengths and limitations. Finally, most relevant open challenges and trends are discussed for providing insights for future research in the field.     

我国移动芯片技术及产业发展若干问题研究

近几年来,移动互联网的发展突飞猛进,带动智能终端成为集成电路产业的新市场,开放式、水平化分工的发展模式为我国移动芯片的发展提供良好契机,也成为带动集成电路产业突破的又一切入点。立足于此大发展的背景,在梳理、对比、分析移动芯片产业发展现状、趋势及特色的同时,重点探讨我国移动芯片技术及产业发展的若干问题,并对我国未来发展提出相关建议。     

我国移动智能终端操作系统平台发展研究

分析移动智能终端操作系统平台发生的一系列技术变革,探讨操作系统平台对于移动互联网产业发展的重大战略意义,揭示当前全球移动智能终端操作系统平台发展格局走向。结合我国产业发展实际,明确了我国发展操作系统平台存在的重大机遇与面临的紧迫形势,指出当前我国操作系统产业面临的三大问题,在此基础上提出发展我国移动智能终端操作系统应借鉴Android运作模式,以"公共平台+差异化"方式采用Android兼容技术路线组织研发,并建议由政府引导透过资本纽带快速形成产业链合力,有效推动我国该产业整体快速发展。