304 research outputs found

    SAMI: Service-Based Arbitrated Multi-Tier Infrastructure for Mobile Cloud Computing

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    Mobile Cloud Computing (MCC) is the state-ofthe- art mobile computing technology aims to alleviate resource poverty of mobile devices. Recently, several approaches and techniques have been proposed to augment mobile devices by leveraging cloud computing. However, long-WAN latency and trust are still two major issues in MCC that hinder its vision. In this paper, we analyze MCC and discuss its issues. We leverage Service Oriented Architecture (SOA) to propose an arbitrated multi-tier infrastructure model named SAMI for MCC. Our architecture consists of three major layers, namely SOA, arbitrator, and infrastructure. The main strength of this architecture is in its multi-tier infrastructure layer which leverages infrastructures from three main sources of Clouds, Mobile Network Operators (MNOs), and MNOs' authorized dealers. On top of the infrastructure layer, an arbitrator layer is designed to classify Services and allocate them the suitable resources based on several metrics such as resource requirement, latency and security. Utilizing SAMI facilitate development and deployment of service-based platform-neutral mobile applications.Comment: 6 full pages, accepted for publication in IEEE MobiCC'12 conference, MobiCC 2012:IEEE Workshop on Mobile Cloud Computing, Beijing, Chin

    An improved port knocking authentication framework for mobile cloud computing

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    The latest developments in mobile cloud computing (MCC) have changed user's priorities for computing. However, the change towards MCC brings new challenges to cloud service providers and administrators. Authentication is one among the challenges categorized in the classification of security issues for MCC. Port knocking authentication method eliminates user's collaboration during the authentication process. Thus, such technique has the potential to be applied on the MCC environment which can ensure reliable communication. However, current port knocking authentication techniques lack of addressing the issue of knock-sequence length. It is challenging to deploy appropriate length sequence for port knocking authentication for the reason that shorter length knock sequence degrades security, whereas, deploying longer length sequence involves performance issues in terms of time and buffer management. This paper proposes a dynamic length port knocking authentication framework which addresses the issue of security degradation and optimizes performance in terms of time up and buffer managment. We employ MikroTik RouterOS for the evaluation of the proposed technique. Analysis of the results shows that dynamic length port knocking authentication technique improves performance in terms of time up to 23% and buffer management up to 28% by reducing the imposed load. Furthermore, by deploying dynamic length (DL) and pool of length (PoL), the proposed method reveals high security, which decreases the probability of hacking knock-sequence near to zero for a number of parallel authentication requests. Hence, dynamic length port knocking authentication technique provides an optimal solution for reliable communication in MCC

    When surgeons are rarer than resources - our experience with improving access to thoracic surgery in an urban setting: A special report

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    With progressive globalisation enabled by technology, there is an increased interest in finding viable solutions to the myriad health problems faced by developing countries. In countries like Pakistan, occasionally the challenge is not a dearth of material resources but rather unavailability of expertise. The current paper was planned to share a model that was successfully implemented in the urban setting of Karachi, Pakistan, from 2012 onwards which significantly improved access to thoracic surgery for underprivileged individuals. Our model focussed on a qualified thoracic surgeon reviving a defunct thoracic surgical unit thereby optimising the use of resources already available in the community. The key to efficient outcomes was direct managerial control by the surgeon who first educated himself in the various processes involved. The model, with its challenges and solutions, has good potential for adaptation in other urban settings in the developing worl

    Simple methods for enhancing bandwidth of a rectangular microstrip patch antenna

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    IoT Based Real Time Early Age Concrete Compressive Strength Monitoring

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    Concrete Strength determination has been an expensive and hectic job due to its orthodox methodology of measuring concrete strength where cylinders are filled with concrete. Its strength is measured using the crushing of concrete (Compression Test). A significant amount of waste is generated while performing this test multiple times during the execution of the project. The present study proposes a new IoT-based framework comprising a low-cost sensor and a window dashboard to estimate and monitor the real-time early-age concrete strength. This system will significantly help the construction industry to avoid the onsite laboratory testing of concrete for strength. In this study, a temperature sensor, along with an ESP32 microprocessor, is used to acquire and transmit the recorded temperature in real time to a cloud database. The window application developed load data from the cloud database and presented it as figures and graphs related to concrete strength with time. The strength calculated using the developed sensor was compared with the actual strength determined using a compression test for the same mix design, which showed a significant match. The project is a contribution toward the non-destructive testing of concrete. By knowing the concrete strength of any structural member in advance, the practitioners can make decisions well before time to avoid delays in the project

    Repair of ascending aortic pseudoaneurysm eroding through the sternum

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    In reoperation for an ascending aortic pseudoaneurysm eroding through the sternum, a left ventricular vent allows careful unhurried sternal division under deep hypothermic circulatory arrest. We repaired ascending aortic pseudoaneurysms in 2 patients who had undergone aortic valve implantation 6 and 21 months earlier. A minithoracotomy was made in the left 5th intercostal space, and a vent was placed in the left ventricular apex. Repair was accomplished with a bovine pericardial patch reinforced with a Teflon felt strip. Both patients made an uneventful recovery with good functional status at discharge at the 8- and 18-month follow-up
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