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Article
Publication date: 22 June 2012

Kerri Stone and Tracy Camp

Localization is a fundamental problem in wireless sensor networks. In many applications, sensor location information is critical for data processing and meaning. While the…

Abstract

Purpose

Localization is a fundamental problem in wireless sensor networks. In many applications, sensor location information is critical for data processing and meaning. While the global positioning system (GPS) can be used to determine mote locations with meter precision, the high hardware cost and energy requirements of GPS receivers often prohibit the ubiquitous use of GPS for location estimates. This high cost (in terms of hardware price and energy consumption) of GPS has motivated researchers to develop localization protocols that determine mote locations based on cheap hardware and localization algorithms. The purpose of this paper is to present a comprehensive review of wireless sensor network localization techniques, and provide a detailed overview for several distance‐based localization algorithms.

Design/methodology/approach

To provide a detailed summary of wireless sensor network localization algorithms, the authors outline a tiered classification system in which they first classify algorithms as distributed, distributed‐centralized, or centralized. From this broad classification, the paper then further categorizes localization algorithms using their protocol techniques. By utilizing this classification system, the authors are able to provide a survey of several wireless sensor network localization algorithms and summarize relative algorithm performance based on the algorithms' classification.

Findings

There are numerous localization algorithms available and the performance of these algorithms is dependent on network configuration, environmental variables, and the ranging method implemented. When selecting a localization algorithm, it is important to understand basic algorithm operation and expected performance. This tier‐based algorithm classification system can be used to gain a high‐level understanding of algorithm performance and energy consumption based on known algorithm characteristics.

Originality/value

Localization is a widely researched field and given the quantity of localization algorithms that currently exist, it is impossible to present a complete review of every published algorithm. Instead, the paper presents a holistic view of the current state of localization research and a detailed review of ten representative distance‐based algorithms that have diverse characteristics and methods. This review presents a new classification structure that may help researchers understand, at a high‐level, the expected performance and energy consumption of algorithms not explicitly addressed by our work.

Details

International Journal of Pervasive Computing and Communications, vol. 8 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

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Article
Publication date: 2 May 2017

Kirubaveni Savarimuthu, Radha Sankararajan and Sudha Murugesan

The purpose of this paper is to present the design of a piezoelectric vibration energy generator with a power conditioning circuit to power a wireless sensor node…

Abstract

Purpose

The purpose of this paper is to present the design of a piezoelectric vibration energy generator with a power conditioning circuit to power a wireless sensor node. Frequency and voltage characterization of the piezoelectric energy harvester is performed. A single-stage AC–DC power converter that integrates the rectification and boosting circuit is designed, simulated and implemented in hardware.

Design/methodology/approach

The designed power conditioning circuit incorporates bridgeless boost rectification, a lithium ion battery as an energy storage unit and voltage regulation to extract maximum power from PZT-5H and to attain higher efficiency. The sensor node is modelled in active and sleep states on the basis of the power consumption. Dynamic modelling of the lithium ion battery with its state of charging and discharging is analysed.

Findings

The test result shows that the energy harvester produces a maximum power of 65.9 mW at the resonant frequency of 21.4 Hz. The designed circuit will operate even at a minimum input voltage of 0.5 V. The output from the harvester is rectified, boosted to a 7-V DC output and regulated to 3.3 V to the power C_Mote wireless sensor node. The conversion efficiency of the circuit is improved to 70.03 per cent with a reduced loss of 19.76 mW.

Originality/value

The performance of the energy harvester and the single-stage power conditioning circuit is analysed. Further, the design and implementation of the proposed circuit lead to an improved conversion efficiency of 70.03 per cent with a reduced loss of 19.76 mW. The vibration energy harvester is integrated with a power conditioning circuit to power a wireless sensor node C_Mote. The piezoelectric vibration energy harvester is implemented in real time to power C_Mote.

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Article
Publication date: 1 February 2004

E. Grant, K.A. Luthy, J.F. Muth, L.S. Mattos, J.C. Braly, A. Seyam, T. Ghosh, A. Dhawan and K. Natarajan

This research deals with the production of electronic textiles (e‐textiles) demonstrators. Initially, the research dealt with the creation of 4×5 microphone array on a…

Abstract

This research deals with the production of electronic textiles (e‐textiles) demonstrators. Initially, the research dealt with the creation of 4×5 microphone array on a large area conformal textile substrate. Once the interface electronics were connected to the 4×5 microphone array, this system became an effective acoustic array. Here, a new acoustic eight microphone array design has been designed, fabricated and tested. Changes were made to improve microphone array performance, and to optimize the associated software for data capture and analysis. This new design was based on UC‐Berkeley mote microcomputer technology. The mote‐based system addresses the issue of scaling acoustic arrays, to allow for distributing microphones over large‐areas, and to allow performance comparisons to be made with the original 4×5 microphone acoustic array.

Details

International Journal of Clothing Science and Technology, vol. 16 no. 1/2
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 31 December 2006

Terry D. May, Shaun H. Dunning, George A. Dowding and Jason O. Hallstrom

Wireless sensor networks (WSNs) will profoundly influence the ubiquitous computing landscape. Their utility derives not from the computational capabilities of any single…

Abstract

Wireless sensor networks (WSNs) will profoundly influence the ubiquitous computing landscape. Their utility derives not from the computational capabilities of any single sensor node, but from the emergent capabilities of many communicating sensor nodes. Consequently, the details of communication within and across single hop neighborhoods is a fundamental component of most WSN applications. But these details are often complex, and popular embedded languages for WSNs provide only low‐level communication primitives. We propose that the absence of suitable communication abstractions contributes to the difficulty of developing large‐scale WSN applications. To address this issue, we present the design and implementation of a Remote Procedure Call (RPC) abstraction for nesC and TinyOS, the emerging standard for developing WSN applications. We present the key language extensions, operating system services, and automation tools that enable the proposed abstraction. We illustrate these contributions in the context of a representative case study, and analyze the overhead introduced when using our approach. We use these results to draw conclusions regarding the suitably of our work to resource‐constrained sensor nodes.

Details

International Journal of Pervasive Computing and Communications, vol. 2 no. 4
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 1 May 1998

Brian H. Kleiner

Presents a special issue, enlisting the help of the author’s students and colleagues, focusing on age, sex, colour and disability discrimination in America. Breaks the…

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Abstract

Presents a special issue, enlisting the help of the author’s students and colleagues, focusing on age, sex, colour and disability discrimination in America. Breaks the evidence down into manageable chunks, covering: age discrimination in the workplace; discrimination against African‐Americans; sex discrimination in the workplace; same sex sexual harassment; how to investigate and prove disability discrimination; sexual harassment in the military; when the main US job‐discrimination law applies to small companies; how to investigate and prove racial discrimination; developments concerning race discrimination in the workplace; developments concerning the Equal Pay Act; developments concerning discrimination against workers with HIV or AIDS; developments concerning discrimination based on refusal of family care leave; developments concerning discrimination against gay or lesbian employees; developments concerning discrimination based on colour; how to investigate and prove discrimination concerning based on colour; developments concerning the Equal Pay Act; using statistics in employment discrimination cases; race discrimination in the workplace; developments concerning gender discrimination in the workplace; discrimination in Japanese organizations in America; discrimination in the entertainment industry; discrimination in the utility industry; understanding and effectively managing national origin discrimination; how to investigate and prove hiring discrimination based on colour; and, finally, how to investigate sexual harassment in the workplace.

Details

Equal Opportunities International, vol. 17 no. 3/4/5
Type: Research Article
ISSN: 0261-0159

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Article
Publication date: 4 December 2017

Zainab Riaz, Erika A. Parn, David J. Edwards, Muhammad Arslan, Charles Shen and Feniosky Pena-Mora

This research aims to investigate the integration of real-time monitoring of thermal conditions within confined work environments through wireless sensor network (WSN…

Abstract

Purpose

This research aims to investigate the integration of real-time monitoring of thermal conditions within confined work environments through wireless sensor network (WSN) technology when integrated with building information modelling (BIM). A prototype system entitled confined space monitoring system (CoSMoS), which provides an opportunity to incorporate sensor data for improved visualization through new add-ins to BIM software, was then developed.

Design/methodology/approach

An empirical study was undertaken to compare and contrast between the performances (over a time series) of various database models to find a back-end database storage configuration that best suits the needs of CoSMoS.

Findings

Fusing BIM data with information streams derived from wireless sensors challenges traditional approaches to data management. These challenges encountered in the prototype system are reported upon and include issues such as hardware/software selection and optimization. Consequently, various database models are explored and tested to find a database storage that best suits the specific needs of this BIM-wireless sensor technology integration.

Originality value

This work represents the first tranche of research that seeks to deliver a fully integrated and advanced digital built environment solution for automating the management of health and safety issues on construction sites.

Details

Journal of Engineering, Design and Technology, vol. 15 no. 6
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 1 April 2005

Li‐teh Sun

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the…

Abstract

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the American preemptive invasion and occupation of Afghanistan and Iraq and the subsequent prisoner abuse, such an existence seems to be farther and farther away from reality. The purpose of this work is to stop this dangerous trend by promoting justice, love, and peace through a change of the paradigm that is inconsistent with justice, love, and peace. The strong paradigm that created the strong nation like the U.S. and the strong man like George W. Bush have been the culprit, rather than the contributor, of the above three universal ideals. Thus, rather than justice, love, and peace, the strong paradigm resulted in in justice, hatred, and violence. In order to remove these three and related evils, what the world needs in the beginning of the third millenium is the weak paradigm. Through the acceptance of the latter paradigm, the golden mean or middle paradigm can be formulated, which is a synergy of the weak and the strong paradigm. In order to understand properly the meaning of these paradigms, however, some digression appears necessary.

Details

International Journal of Sociology and Social Policy, vol. 25 no. 4/5
Type: Research Article
ISSN: 0144-333X

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Article
Publication date: 14 July 2021

Sakshi Garg, Deepti Mehrotra, Sujata Pandey and Hari Mohan Pandey

This paper aims to determine the network efficient topology for low power and lossy networks (LLNs) using routing protocol for LLN (RPL) with respect to the increase in…

Abstract

Purpose

This paper aims to determine the network efficient topology for low power and lossy networks (LLNs) using routing protocol for LLN (RPL) with respect to the increase in network size and propose a novel approach to overcome the shortcomings of the existing models.

Design/methodology/approach

The authors have used Contiki OS/Cooja simulator to conduct experiments on primarily four topologies (star, bus/linear, ring/eclipse and random). They have implemented RPL protocol using Sky motes for each topology from 10, 20, 30 and up to 70 nodes. Consequently, after 24 h of experimentation, the readings have been noted and, alongside, a comprehensive comparative analysis has been performed based on the network density and metric parameters: packet delivery ratio (PDR), expected transmission (ETX) and power consumption. Further, a hybrid model is proposed where the additional factors of mobility, multiple sink and a combination of static and mobile nodes are introduced. The proposed model is then compared with the star model (all static nodes and star topology) and the dynamic model (all mobile nodes) to analyze the efficiency and network performance for different network sizes (28, 36, 38 and 44 nodes). The mobility is introduced using BonnMotion tool in Contiki OS.

Findings

Simulation results have shown that the star topology is most network efficient when compared with bus/linear, ring/eclipse and random topologies for low density and high scalable network. But when the same setup is compared with the proposed hybrid model, the proposed model shows a significant improvement and gives the best and efficient network performance with highest PDR (average improvement approximately 44.5%) and lowest ETX (average improvement approximately 49.5%) comparatively.

Practical implications

Also, these findings will benefit the deployment of smart devices used in advanced metering infrastructure, road side units and in various industrial applications such as traffic monitoring system, electronic toll collection and traffic analysis in the smart grid infrastructure.

Originality/value

The impact of topology is significant and detailed analysis is required to understand the impact of different topologies of the nodes in the network for the present and the future scenarios. As very few research studies have discussed this gap, this research paper is quintessential and shall open novel future potential direction. Also, the proposed approach of hybrid model with mobility has not been considered in the literature yet.

Details

International Journal of Pervasive Computing and Communications, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1742-7371

Keywords

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Book part
Publication date: 11 May 2007

William S. Keeton, Philip W. Mote and Jerry F. Franklin

Climate change during the next century is likely to significantly influence forest ecosystems in the western United States, including indirect effects on forest and…

Abstract

Climate change during the next century is likely to significantly influence forest ecosystems in the western United States, including indirect effects on forest and shrubland fire regimes. Further exacerbation of fire hazards by the warmer, drier summers projected for much of the western U.S. by climate models would compound already elevated fire risks caused by 20th century fire suppression. This has potentially grave consequences for the urban–wildland interface in drier regions, where residential expansion increasingly places people and property in the midst of fire-prone vegetation. Understanding linkages between climate variability and change, therefore, are central to our ability to forecast future risks and adapt land management, allocation of fire management resources, and suburban planning accordingly. To establish these linkages we review previous research and draw inferences from our own retrospective work focused on 20th century climate–fire relationships in the U.S. Pacific Northwest (PNW). We investigated relationships between the two dominant modes of climate variability affecting the PNW, which are Pacific Decadal Oscillation (PDO) and El Niño/Southern Oscillation (ENSO), and historic fire activity at multiple spatial scales. We used historic fire data spanning most of the 20th century for USDA Forest Service Region 6, individual states (Idaho, Oregon, and Washington), and 20 national forests representative of the region's physiographic diversity. Forest fires showed significant correlations with warm/dry phases of PDO at regional and state scales; relationships were variable at the scale of individual national forests. Warm/dry phases of PDO were especially influential in terms of the occurrence of very large fire events throughout the PNW. No direct statistical relationships were found between ENSO and forest fires at regional scales, although relationships may exist at smaller spatial scales. However, both ENSO and PDO were correlated with summer drought, as estimated by the Palmer Drought Severity Index (PDSI), and PDSI was correlated with fire activity at all scales. Even moderate (±0.3°C decadal mean) fluctuations in PNW climate over the 20th century have influenced wildfire activity based on our analysis. Similar trends have been reported for other regions of the western U.S. Thus, forest fire activity has been sensitive to past climate variability, even in the face of altered dynamics due to fire suppression, as in the case of our analysis. It is likely that fire activity will increase in response to future temperature increases, at the same or greater magnitude as experienced during past climate variability. If extreme drought conditions become more prevalent we can expect a greater frequency of large, high-intensity forest fires. Increased vulnerability to forest fires may worsen the current fire management problem in the urban–wildland interface. Adaptation of fire management and restoration planning will be essential to address fire hazards in areas of intermingled exurban development and fire-prone vegetation. We recommend: (1) landscape-level strategic planning of fire restoration and containment projects; (2) better use of climatic forecasts, including PDO and ENSO related predictions; and (3) community-based efforts to limit further residential expansion into fire-prone forested and shrubland areas.

Details

Living on the Edge
Type: Book
ISBN: 978-1-84950-000-5

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Article
Publication date: 30 January 2019

Erika A. Parn, David Edwards, Zainab Riaz, Fahad Mehmood and Joseph Lai

This paper aims to report upon the further development of a hybrid application programming interface (API) plug-in to building information modelling (BIM) entitled…

Abstract

Purpose

This paper aims to report upon the further development of a hybrid application programming interface (API) plug-in to building information modelling (BIM) entitled confined spaces safety monitoring system “CoSMoS”. Originally designed to engineer-out environmental hazards associated with working in a building’s confined spaces (during the construction phase of a building’s life-cycle), this second generation version is expanded upon to use archival records to proactively learn from data generated within a sensor network during the building’s operations and maintenance (O&M) phase of asset management (AM).

Design/methodology/approach

An applied research methodological approach adopted used a two-phase process. In phase one, a conceptual model was created to provide a “blueprint map” to integrate BIM, sensor-based networks and data analytics (DA) into one integral system. A literature review provided the basis for the conceptual model’s further development. In phase two, the conceptual model was transposed into the prototype’s development environment as a proof of concept using primary data accrued from a large educational building.

Findings

An amalgamation of BIM, historical sensor data accrued and the application of DA demonstrate that CoSMoS provides an opportunity for the facilities management (FM) team to monitor pertinent environmental conditions and human behaviour within buildings that may impact upon occupant/worker safety. Although working in confined spaces is used to demonstrate the inherent potential of CoSMoS, the system could readily be expanded to analyse sensor-based network’s historical data of other areas of building performance, maintenance and safety.

Originality/value

This novel prototype has automated safety applications for FM during the asset lifecycle and maintenance phase of a building’s O&M phase of AM. Future work is proposed in several key areas, namely, develop instantaneous indicators of current safety performance within a building; and develop lead indicators of future safety performance of buildings.

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