416 research outputs found

    Strength, water absorption and thermal comfort of mortar bricks containing crushed ceramic waste

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    This present study investigated the crushed ceramic waste utilisation as sand replacement in solid mortar bricks. The percentage of crushed ceramic waste used were 0% (CW0), 10% (CW10), 20% (CW20) and 30% (CW30) from the total weight of sand. The dimension prescribed of mortar bricks are 215 mm x 102.5 mm x 65 mm as followed accordance to MS 2281:2010 and BS EN 771-1:2011+A1:2015. Four (4) tests were conducted on mortar bricks namely crushing strength, water absorption, compressive strength of masonry units and thermal comfort. The incorporation of ceramic waste in all designated mortar bricks showed the increment of crushing strength between 23% and 46% at 28 days of curing and decrement water absorption between 34% and 44% was recorded corresponding to control mortar bricks. The prism test of masonry units consists of mortar bricks containing ceramic waste indicated the high increment of compressive strength at about 200% as compared to mortar brick without ceramic waste. The thermal comfort test of ceramic mortar bricks were also showed the good insulation with low interior temperature. Therefore, the ceramic waste can be utilised as a material replacement to fine aggregate in mortar brick productions due to significant outcomes performed

    Hybrid cargo-level tracking system for logistics

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    In this paper, we propose a hybrid cargo-level tracking system for logistics. We highlight the special system requirements, discuss the design issues and identify the design principles. Then we propose an innovative hybrid system. As far as we know, this is the first system that exploits both infrastructure-based and infrastructure-less positioning schemes for practical cargo-level tracking. Compared with existing systems, the proposed system provides a ubiquitous cargo-level tracking solution with enhanced availability, reliability, and lower total costs. © 2010 IEEE.published_or_final_versionThe 71st IEEE Vehicular Technology Conference (VTC2010-Spring), Taipei, Taiwan, 16-19 May 2010. In Proceedings of 71st IEEE-VTC (Spring), 2010, p. 1-

    Goodbye, ALOHA!

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    ©2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The vision of the Internet of Things (IoT) to interconnect and Internet-connect everyday people, objects, and machines poses new challenges in the design of wireless communication networks. The design of medium access control (MAC) protocols has been traditionally an intense area of research due to their high impact on the overall performance of wireless communications. The majority of research activities in this field deal with different variations of protocols somehow based on ALOHA, either with or without listen before talk, i.e., carrier sensing multiple access. These protocols operate well under low traffic loads and low number of simultaneous devices. However, they suffer from congestion as the traffic load and the number of devices increase. For this reason, unless revisited, the MAC layer can become a bottleneck for the success of the IoT. In this paper, we provide an overview of the existing MAC solutions for the IoT, describing current limitations and envisioned challenges for the near future. Motivated by those, we identify a family of simple algorithms based on distributed queueing (DQ), which can operate for an infinite number of devices generating any traffic load and pattern. A description of the DQ mechanism is provided and most relevant existing studies of DQ applied in different scenarios are described in this paper. In addition, we provide a novel performance evaluation of DQ when applied for the IoT. Finally, a description of the very first demo of DQ for its use in the IoT is also included in this paper.Peer ReviewedPostprint (author's final draft

    Embedded System for Construction Material Tracking Using Combination of Radio Frequency and Ultrasound Signal

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    This study created a framework for integrating the latest innovations in wireless sensor network that automate tracking and monitoring construction assets, e.g. equipment, materials, and labor in construction sites. This research constitutes one of the few studies to incorporate emerging information and sensor network technologies with the construction industry, which has been slow to migrate away from legacy processes. The presented research works introduce a new prototype framework of an automated tracking system that will address the needed shift from the time-and labor-intensive legacy systems to sensor- and network-based collaboration and communication systems for construction processes. Software and hardware architecture for the new tracking system was developed using the combination of ultrasound and radio signals. By embedding the external ultrasound device with a MICAZ platform, enhancements to networking flexibility and wireless communication was observed over the previous technologies used in the construction material tracking systems. Feasibility study and testbed experiment on the position estimation were implemented to verify the localization algorithm presented in this dissertation. Cost benefit analysis based on quantitative approach implied that the presented framework can save the implementation cost of material tracking by up to 64 percent in a typical construction project. In addition to cost savings, the use of sensor-based tracking system can provide the intangible, comprehensive benefits in communication, labor utilization, document management, and resource management. It is hoped that the present work will describe a system that can effectively be used in a range of applications for tracking and monitoring purposes and will present a clear path that engineers can take to use existing wireless sensor technology in their particular applications. The cost of such hardware will decrease rapidly, thereby permitting large numbers of application scenarios to be possible in many construction sites with improved energy consumption, hardware performance, durability, and safety

    Federated Sensor Network architectural design for the Internet of Things (IoT)

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    An information technology that can combine the physical world and virtual world is desired. The Internet of Things (IoT) is a concept system that uses Radio Frequency Identification (RFID), WSN and barcode scanners to sense and to detect physical objects and events. This information is shared with people on the Internet. With the announcement of the Smarter Planet concept by IBM, the problem of how to share this data was raised. However, the original design of WSN aims to provide environment monitoring and control within a small scale local network. It cannot meet the demands of the IoT because there is a lack of multi-connection functionality with other WSNs and upper level applications. As various standards of WSNs provide information for different purposes, a hybrid system that gives a complete answer by combining all of them could be promising for future IoT applications. This thesis is on the subject of `Federated Sensor Network' design and architectural development for the Internet of Things. A Federated Sensor Network (FSN) is a system that integrates WSNs and the Internet. Currently, methods of integrating WSNs and the Internet can follow one of three main directions: a Front-End Proxy solution, a Gateway solution or a TCP/IP Overlay solution. Architectures based on the ideas from all three directions are presented in this thesis; this forms a comprehensive body of research on possible Federated Sensor Network architecture designs. In addition, a fully compatible technology for the sensor network application, namely the Sensor Model Language (SensorML), has been reviewed and embedded into our FSN systems. The IoT as a new concept is also comprehensively described and the major technical issues discussed. Finally, a case study of the IoT in logistic management for emergency response is given. Proposed FSN architectures based on the Gateway solution are demonstrated through hardware implementation and lab tests. A demonstration of the 6LoWPAN enabled federated sensor network based on the TCP/IP Overlay solution presents a good result for the iNET localization and tracking project. All the tests of the designs have verified feasibility and achieve the target of the IoT concept

    A Survey on Facilities for Experimental Internet of Things Research

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    International audienceThe initial vision of the Internet of Things (IoT) was of a world in which all physical objects are tagged and uniquelly identified by RFID transponders. However, the concept has grown into multiple dimensions, encompassing sensor networks able to provide real-world intelligence and goal-oriented collaboration of distributed smart objects via local networks or global interconnections such as the Internet. Despite significant technological advances, difficulties associated with the evaluation of IoT solutions under realistic conditions, in real world experimental deployments still hamper their maturation and significant roll out. In this article we identify requirements for the next generation of the IoT experimental facilities. While providing a taxonomy, we also survey currently available research testbeds, identify existing gaps and suggest new directions based on experience from recent efforts in this field

    From serendipity to sustainable Green IoT: technical, industrial and political perspective

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    Recently, Internet of Things (IoT) has become one of the largest electronics market for hardware production due to its fast evolving application space. However, one of the key challenges for IoT hardware is the energy efficiency as most of IoT devices/objects are expected to run on batteries for months/years without a battery replacement or on harvested energy sources. Widespread use of IoT has also led to a largescale rise in the carbon footprint. In this regard, academia, industry and policy-makers are constantly working towards new energy-efficient hardware and software solutions paving the way for an emerging area referred to as green-IoT. With the direct integration and the evolution of smart communication between physical world and computer-based systems, IoT devices are also expected to reduce the total amount of energy consumption for the Information and Communication Technologies (ICT) sector. However, in order to increase its chance of success and to help at reducing the overall energy consumption and carbon emissions a comprehensive investigation into how to achieve green-IoT is required. In this context, this paper surveys the green perspective of the IoT paradigm and aims to contribute at establishing a global approach for green-IoT environments. A comprehensive approach is presented that focuses not only on the specific solutions but also on the interaction among them, and highlights the precautions/decisions the policy makers need to take. On one side, the ongoing European projects and standardization efforts as well as industry and academia based solutions are presented and on the other side, the challenges, open issues, lessons learned and the role of policymakers towards green-IoT are discussed. The survey shows that due to many existing open issues (e.g., technical considerations, lack of standardization, security and privacy, governance and legislation, etc.) that still need to be addressed, a realistic implementation of a sustainable green-IoT environment that could be universally accepted and deployed, is still missing

    A wireless network system for automated tracking of construction materials on project sites

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    This paper presents a new prototype framework of automated tracking and monitoring system for construction materials. Previous technologies such as RFID and GPS deployed in construction material tracking have been reviewed and signal strength‐based localisation has been examined. As an emerging network standard for industrial applications, brief specifications of ZigBee™ protocol have been described. We introduce a ZigBee‐based tracking system architecture using hybrid techniques of RF and ultrasound to improve positioning accuracy and cost benefit. Finally, feasibility analysis and application scenario have been examined to present the possible deployment framework in construction area. Santrauka Straipsnyje aprašomas naujas automatizuotos statybinių medžiagų stebėsenos sistemos modelis. Apžvelgiamos tokios technologijos, kaip RFID ir GPS, anksčiau naudotos stebint statybines medžiagas, ir nagrinėjamas signalo stiprumu pagrįstas lokalizavimas. Aprašoma tinklo standarto ZigBee™ protokolo, naudojamo pramonėje, specifikacija. Pateikiama ZigBee tipo stebėjimo sistema, naudojanti RF ir ultragarso technologiją, skirtą pozicionavimo tikslumui gerinti ir jo kainai mažinti. Be to, pateikiama sistemos galimybių analizė ir taikymo sistema, nagrinėjanti galimą šios sistemos naudojimą statyboje. First Published Online: 14 Oct 2010 Reikšminiai žodžiai: ZigBee, daviklių tinklas, stebėjimas, kontrolė, statybinės medžiagos, lokalizavimo technika
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