Web data are experiencing a proliferation of video content for mobile platforms. This is accompanied by new advances in heterogeneous general purpose processor (GPP) cores embedded in mobile devices ...which offer a great opportunity to enhance both performance and energy efficiency of software (SW) video decoding. On the other hand, hardware (HW) video accelerators are more energy-efficient but are not flexible and their time-to-market is significant. In this context, this paper proposes a characterization methodology to investigate the performance and power consumption of two video decoding approaches on mobile platforms. The first one uses a HW decoder intellectual property (HDIP) in addition to a GPP (for the control). The second one is SW-based and uses only a heterogeneous multi-core GPP. The objective is to study the behavior of both video decoding approaches by comparing them and to understand why and in which case it is worth relying on the GPP rather than the HDIP. We also derive the optimal GPP configuration (number of cores and their frequency) that minimizes the energy consumption for a given video bit-stream on a given platform. The proposed methodology was applied on the HEVC video codec standard. In some state-of-the-art work figures, the SW video decoding consumes up to 1000× more energy than HDIPs. Our results show that, for video resolutions of 1080p and lower and at the operating system perspective point of view, the HEVC SW decoding consumes on average less than 4× more energy (mJ/Frame) than the HW one. Then, the more we scale up the resolution, the more we get the advantage of using the HW video decoding. Furthermore, the HEVC HW and SW decoders consume effectively less than 30% and 50% of the global power consumption of the tested platforms, respectively.
To address the problems of conventional mobile platforms for mobile manipulators, this article proposes the design and control of a new type of mobile platform, whose locomotion method is based on ...constant rotation. The proposed mobile platform is actuated by three conventional wheels, each of which is connected to the main body by a single-DOF passive planar motion mechanism. By rotating the platform during locomotion, multidirectional translation can be realized by avoiding singular configurations. The proposed mobile platform offers benefits in terms of high maneuverability, high precision, and low vibration. In this article, the mechanism and kinematics of the proposed mobile platform are first presented. Based on the singularity analysis, applicable locomotion methods and the design conditions of the planar motion mechanism are discussed. An example of the proposed mobile platform is introduced, and its kinematic characteristics and approximate model are then presented. To achieve obstacle and tip-over avoidance, a trajectory tracking control system based on model predictive control and a path planner was also developed. Finally, experiments using the prototype are presented. The results verify the effectiveness of the developed mobile platform and its control strategies.
•A real-time, interactive, and easy-to-use virtual pottery design system, which is available as Apps in Android and Apple stores.•A large amount of pre-collected classic models and painting ...decorations for design reference.•Offers a platform for flexible and personalized manufacture via interactive components and industrial constraints.
We present Wowtao, an easy-to-use pottery manufacture system to take digital creativity into the real world. Our approach is able to create customized pottery virtually on mobile phones or tablet computers interactively and quickly. Our work takes integration of the customer in product personalization into consideration to support personal design in pottery manufacture field.
Different from other virtual pottery design systems, our approach simulates the entire physical pottery design process, such as modeling, painting, seals, firing and customization, and provides the ability to have the designed results fabricated by real artists or a 3D printer. To make the designed results manufacturable by artists, our approach imposes some industrial constraints (both geometry and decorations) when the user designs his/her personalized potteries. Our method only requires simple and intuitive interactions, so even novices can follow the workflow to create pretty potteries easily. We optimize the design process to perform real-time operations. Our informal user study shows that a first-time user typically masters the operations within 10 minutes, and can construct interesting and satisfactory 3D pottery models within minutes.
According to the requirements and characteristics of mobile Internet content security audit, designed and implemented the mobile Internet content security audit system. The system captured and ...processed data through a data acquisition proxy server for mobile user network access, and then set keywords by matching rules, finally carried out the content audit through the single mode and multi pattern matching algorithm.
The digital divide in rural areas is an important social issue, especially in developing countries. Although Internet and broadband penetration have increased in the world generally, there are many ...obstacles for rural China to get access to ICT (Information and Communication Technology) and its services. The mobile platform is regarded as a novel and effective tool to reduce the digital divide. Based on a case of one mobile platform, namely WeCountry in Chinese rural areas, this study illustrates how a mobile platform bridges the digital divide and helps rural areas achieve social inclusion. Results show that: (1) the mobile platform mainly acts on the digital capability divide elimination, and it has to guide and increase users’ usage capability; (2) the mobile platform can empower villagers in structural, psychological, and resource dimensions, achieving political inclusion, social participation inclusion, and economic inclusion; (3) platform providers and government are key organizations during the divide elimination process. This paper concludes with theoretical and practical implications.
We explore the task of Android malware detection based on dynamic analysis of application activity sequences using deep learning techniques. We show that analyzing a sequence of the activities is ...informative for detecting malware, but that analyzing longer sequences does not necessarily lead to a more accurate model. In the real-world scenario, the number of malware is low compared to that of harmless applications. Our dataset has more than 180,000 samples, two-thirds of which are malware. This dataset is significantly larger than other datasets used in previous studies. We mimic real-world cases by randomly sampling a small portion of malware samples. Using the state-of-the-art model BERT, we show that it is possible to achieve desired malware detection performance with an extremely unbalanced dataset. We find that our BERT based model achieves an F1 score of 0.919 with just 0.5% of the examples being malware, which significantly outperforms current state-of-the-art approaches. The results validate the effectiveness of our proposed method in dealing with highly imbalanced datasets.
Recently, it is becoming increasingly possible to apply aerial transportation systems to real-world applications. However, current researches on cable-suspended transportation systems present ...practical limitations due to the fixed-length cable. With the introduction of the cable adjustment mechanism, various complicated tasks, such as limited space crossing, offshore sample collection, and even landing the payload on a mobile platform, can be accomplished by actively changing the distance between the quadrotor and the payload. In order to complete the aforementioned tasks, a trajectory tracking control method is in urgent need for the variable-length-cable-suspended aerial transportation systems. To this end, an adaptive tracking control approach with the consideration of unknown resistance coefficients is designed in this paper. Subsequently, Lyapunov techniques and Barbalat's Lemma are utilized to prove the convergence for the equilibrium point of the closed-loop system. Finally, hardware experiments are meticulously conducted based on a self-built experimental platform, which verify the satisfactory performance of the proposed method in anti-swing aerial transportation and payload landing onto the mobile platform.
The article discusses a new mobile robotic platform with an autonomous stabilization system for reconnaissance operations. A developed 3D model of a mobile robotic platform with an autonomous ...stabilization system for reconnaissance operations is presented. The main stages of designing a model of a movable mounting block for optical sensors of a mobile platform are described. The modularity and functionality of the optical sensor mounting block is ensured. The mounting block provides several options for mounting cameras: two cameras or one camera at the same time. Such modularity makes it possible to change the variability of the equipment on the camera mounting block. The optical sensor mounting block consists of several parts: the base, the main frame, the auxiliary mount, the camera mount, and the thermal imager mount. Drawings of 3D models of each constituent element are given. The description of the process of preparation of the technology for manufacturing a prototype of a movable mount for optical sensors based on 3D printing by FDM technology is given. Using the example of a cylindrical base for a block of optical sensors, all the features of setting up 3D printing technology are described.
Large lightweight slender links mounted on mobile robots enlarge their workspace. This work presents one of these robots that has been endowed with 4 legs to improve its static stability—which is put ...at risk by the large link—and help in the positioning of the link. The efficiency of this system depends on its accuracy in positioning and orientating the end-effector placed at the tip of the link, which is compromised by vibrations that appear in the link during the movement and permanent deflections caused by gravity. A relatively simple control scheme that combines a feedback control of the pose of the mobile platform with a feedforward term that orientates the link is proposed. It uses three legs as actuators; and feeds back measurements of the extensions of the three legs and the orientation of the platform given by an inertial sensor placed in the upper part of the mobile platform. Based on the flatness property of a simplified dynamic model of the link, its dynamics can be easily inverted, being used to implement the proposed feedforward term. Since such feedforward term is used, extra sensors to measure the deflection of the link are not needed, and since the legs are used to move the link, extra actuators mounted on the link are neither needed. All this allows us to reduce the weight and the volume of the payload carried by the mobile platform. Results obtained through a finite elements software and experimentation of the real prototype show the good performance attained with the proposed control strategy.
To prevent unauthorized apps from retrieving the sensitive data, Android framework enforces a permission based access control. However, it has long been known that, to bypass the access control, ...unauthorized apps can intercept the Intent objects which are sent by authorized apps and carry the retrieved sensitive data. We find that there is a new (previously unknown) attack surface in Android framework that can be exploited by unauthorized apps to violate the access control. Specifically, we discover that part of Intent objects that are sent by Android framework and carry sensitive data can be received by unauthorized apps, resulting in the leak of sensitive data. In this paper, we conduct the first systematic investigation on the new attack surface namely the Intent based leak of sensitive data in Android framework. To automatically uncover such kind of vulnerability in Android framework, we design and develop a new tool named LeakDetector, which finds the Intent objects sent by Android framework that can be received by unauthorized apps and carry the sensitive data. Applying LeakDetector to 10 commercial Android systems, we find that it can effectively uncover the Intent based leak of sensitive data in Android framework. Specifically, we discover 36 exploitable cases of such kind of data leak, which can be abused by unauthorized apps to steal the sensitive data, violating the access control. At the time of writing, 16 of them have been confirmed by Google, Samsung, and Xiaomi, and we received bug bounty rewards from these mobile vendors.
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