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Computers, Volume 7, Issue 4 (December 2018)

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Open AccessArticle Run-Time Mitigation of Power Budget Variations and Hardware Faults by Structural Adaptation of FPGA-Based Multi-Modal SoPC
Received: 13 July 2018 / Revised: 5 October 2018 / Accepted: 7 October 2018 / Published: 11 October 2018
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Abstract
Systems for application domains like robotics, aerospace, defense, autonomous vehicles, etc. are usually developed on System-on-Programmable Chip (SoPC) platforms, capable of supporting several multi-modal computation-intensive tasks on their FPGAs. Since such systems are mostly autonomous and mobile, they have rechargeable power sources and
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Systems for application domains like robotics, aerospace, defense, autonomous vehicles, etc. are usually developed on System-on-Programmable Chip (SoPC) platforms, capable of supporting several multi-modal computation-intensive tasks on their FPGAs. Since such systems are mostly autonomous and mobile, they have rechargeable power sources and therefore, varying power budgets. They may also develop hardware faults due to radiation, thermal cycling, aging, etc. Systems must be able to sustain the performance requirements of their multi-task multi-modal workload in the presence of variations in available power or occurrence of hardware faults. This paper presents an approach for mitigating power budget variations and hardware faults (transient and permanent) by run-time structural adaptation of the SoPC. The proposed method is based on dynamically allocating, relocating and re-integrating task-specific processing circuits inside the partially reconfigurable FPGA to accommodate the available power budget, satisfy tasks’ performances and hardware resource constraints, and/or to restore task functionality affected by hardware faults. The proposed method has been experimentally implemented on the ARM Cortex-A9 processor of Xilinx Zynq XC7Z020 FPGA. Results have shown that structural adaptation can be done in units of milliseconds since the worst-case decision-making process does not exceed the reconfiguration time of a partial bit-stream. Full article
(This article belongs to the Special Issue Reconfigurable Computing Technologies and Applications)
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Open AccessArticle Ontology Middleware for Integration of IoT Healthcare Information Systems in EHR Systems
Received: 14 September 2018 / Revised: 28 September 2018 / Accepted: 4 October 2018 / Published: 8 October 2018
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Abstract
Healthcare sectors have been at the forefront of the adoption and use of IoT technologies for efficient healthcare diagnosis and treatment. Because healthcare IoT sensor technology obtains health-related data from patients, it needs to be integrated with the electronic healthcare records (EHR) system.
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Healthcare sectors have been at the forefront of the adoption and use of IoT technologies for efficient healthcare diagnosis and treatment. Because healthcare IoT sensor technology obtains health-related data from patients, it needs to be integrated with the electronic healthcare records (EHR) system. Most EHR systems have not been designed for integration with IoT technology; they have been designed to be more patient-centric management systems. The use of the IoT in EHR remains a long-term goal. Configuring IoT in EHR can enhance patient healthcare, enabling health providers to monitor their patients outside of the clinic. To assist physicians to access data resources efficiently, a data model that is semantic and flexible is needed to connect EHR data and IoT data that may help to provide true interoperability and integration. This research proposes a semantic middleware that exploits ontology to support the semantic integration and functional collaborations between IoT healthcare Information Systems and EHR systems. Full article
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Open AccessArticle Distance-Constrained Outage Probability Analysis for Device-to-Device Communications Underlaying Cellular Networks with Frequency Reuse Factor of 2
Received: 10 September 2018 / Revised: 5 October 2018 / Accepted: 5 October 2018 / Published: 6 October 2018
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Abstract
Device-to-device (D2D) communication is affirmed as one of the dynamic techniques in improving the network throughput and capacity and reducing traffic load to the evolved Node B (eNB). In this paper, we propose a resource allocation and power control technique in which two-pairs
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Device-to-device (D2D) communication is affirmed as one of the dynamic techniques in improving the network throughput and capacity and reducing traffic load to the evolved Node B (eNB). In this paper, we propose a resource allocation and power control technique in which two-pairs of D2D users can simultaneously share same uplink cellular resource. In this case, interference between D2D users and cellular users is no longer insignificant so it must be properly handled. The proposed scheme considers fractional frequency reuse (FFR) scheme as a promising method that can relatively reduce the intra-cell interference. The main objective of the proposed scheme is to maximize the D2D communication throughput and overall system throughput by minimizing outage probability. Hence, we formulate an outage probability problem and overall system throughput optimization problem while guaranteeing minimum allowable signal-to-interference-plus-noise ratio (SINR). For fair distribution of cellular resources to multiple D2D pairs, we used Jain's fairness index (JFI) method. Simulation is conducted in MATLAB and our simulation results demonstrate that the proposed scheme achieves remarkable system performance as compared with existing methods. Full article
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Open AccessArticle An Empirical Study on Security Knowledge Sharing and Learning in Open Source Software Communities
Received: 19 July 2018 / Revised: 20 September 2018 / Accepted: 28 September 2018 / Published: 1 October 2018
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Abstract
Open source software (OSS) security has been the focus of the security community and practitioners over the past decades. However, the number of new vulnerabilities keeps increasing in today’s OSS systems. With today’s increasingly important and complex OSS, lacking software security knowledge to
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Open source software (OSS) security has been the focus of the security community and practitioners over the past decades. However, the number of new vulnerabilities keeps increasing in today’s OSS systems. With today’s increasingly important and complex OSS, lacking software security knowledge to handle security vulnerabilities in OSS development will result in more breaches that are serious in the future. Learning software security is a difficult and challenging task since the domain is quite context specific and the real project situation is necessary to apply the security concepts within the specific system. Many OSS proponents believe that the OSS community offers significant learning opportunities from its best practices. However, studies that specifically explore security knowledge sharing and learning in OSS communities are scarce. This research is intended to fill this gap by empirically investigating factors that affect knowledge sharing and learning about software security and the relationship among them. A conceptual model is proposed that helps to conceptualize the linkage between socio-technical practices and software security learning processes in OSS communities. A questionnaire and statistical analytical techniques were employed to test hypothesized relationships in the model to gain a better understanding of this research topic. Full article
(This article belongs to the Special Issue Software Security and Assurance)
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Open AccessFeature PaperArticle Performance Evaluation of HARQ Schemes for the Internet of Things
Received: 20 August 2018 / Revised: 14 September 2018 / Accepted: 21 September 2018 / Published: 25 September 2018
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Abstract
Hybrid Automatic Repeat reQuest (HARQ) techniques are widely employed in the most important wireless systems, e.g., the Long Term Evolution (LTE) cellular standard, to increase the reliability of the communication. Despite these schemes have been widely studied in literature in the past several
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Hybrid Automatic Repeat reQuest (HARQ) techniques are widely employed in the most important wireless systems, e.g., the Long Term Evolution (LTE) cellular standard, to increase the reliability of the communication. Despite these schemes have been widely studied in literature in the past several years, the recent results obtained by Polyanskiy, Poor, and Verdú on the finite-blocklength regime disclosed new possibilities for the research on HARQ schemes. Indeed, new communications trends, which are usually part of the Internet of Things (IoT) paradigm, are characterized by very short packet sizes and a high reliability requirement and, therefore, they call for efficient HARQ techniques. In many scenarios, the energy efficiency of the communication plays a key role as well. In this paper, we aim at providing a comprehensive performance comparison of various kinds of HARQ schemes in the context of short-packet transmissions with energy constraints. We derive optimal power allocation strategies and we show that a minimum 50% energy saving can be achieved after very few transmission attempts if we enable packet combining at the receiver side. Full article
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Open AccessArticle Connecting Smart Objects in IoT Architectures by Screen Remote Monitoring and Control
Received: 22 August 2018 / Revised: 14 September 2018 / Accepted: 22 September 2018 / Published: 24 September 2018
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Abstract
Electronic visual display enabled by touchscreen technologies evolves as one of the universal multimedia output methods and a popular input intermediate with touch–interaction. As a result, we can always gain access of an intelligent machine by obtaining control of its display contents. Since
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Electronic visual display enabled by touchscreen technologies evolves as one of the universal multimedia output methods and a popular input intermediate with touch–interaction. As a result, we can always gain access of an intelligent machine by obtaining control of its display contents. Since remote screen sharing systems are also increasingly prevalent, we propose a cross-platform middleware infrastructure which supports remote monitoring and control functionalities based on remote streaming for networked intelligent devices such as smart phone, computer and smart watch, etc. and home appliances such as smart refrigerator, smart air-conditioner and smart TV, etc. We aim to connect all these devices with display screens, so as to make possible remote monitoring and controlling a certain device by whichever one (usually the nearest one) of display screens among the network. The system is a distributed network consisting of multiple modular nodes of server and client, and is compatible to prevalent operating systems such as Windows, macOS, Unix-like/Linux and Android, etc. Full article
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