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Article
Publication date: 12 June 2017

Priyadarshi Biplab Kumar and Dayal R. Parhi

Being an interdisciplinary research area, biomechanics has gained interest among researchers. Biomechanics deals with integration of mechanical phenomenon with the…

Abstract

Purpose

Being an interdisciplinary research area, biomechanics has gained interest among researchers. Biomechanics deals with integration of mechanical phenomenon with the structural and functional aspects of biological systems. Biological systems being very much complex provide a very intricate platform for their analysis. In case of damages created by accidents or sport malfunctions, artificial implants are used for the replacement of bones. These implants may cause incompatibility with the human body, depending on their design and characterization. So, this research aims to analyze the vibrational characteristics of a human femur bone and to predict the safe ranges of frequencies of operation.

Design/methodology/approach

The current research is aimed at vibrational characterization of a human femur bone. The model of the femur bone is prepared using SOLIDWORKS software. The material properties of the femur are collected from the available literature and provided with the CAD model. The model is imported to the ANSYS software. Loading patterns as applied on the human body are also applied to the prepared model. Suitable boundary conditions are chosen for normal sitting and standing positions. The natural frequencies of the femur bone and other vibrational parameters are found out.

Findings

The first data obtained from the ANSYS software are the natural frequencies and mode shapes of vibration. Other data include the stress distributions, strain distributions, deformation patterns and potential zones of damage. The frequencies and mode shapes enable the safe ranges of human operation and the frequency range to be followed in the designing of implants. The stress distributions enable to know the potential zones of damage so that those areas can be given focus during strength considerations.

Research limitations/implications

The current investigations take into account only normal sitting and walking conditions. This work can be included under static loadings. This can also be extended toward dynamic loading conditions. In the dynamic loading, walking and running conditions can be taken into account. This work focuses on the safe designing of the artificial implants and their compatibility with the human body. This can also be extended toward role of dynamic forces in the damaged bone formation and the role of implant’s characteristics for healing of bones.

Practical implications

Bone damage and ligament fracture are common nowadays due to increasing number of accidents, which may be vehicular or sports. In case of any damage to the skeletal parts, some artificial implant is used to support the damaged part and to help in the process of healing. The designing of the implants must be compatible with the human body. The natural frequencies and mode shapes give an idea that the vibrational parameters of the implant material must fall in the same range as the actual bone. The stress distribution and potential zone damage emphasize on strength considerations.

Originality/value

The current method is a novel approach toward implant designing. Here an analysis of vibrational parameters of the human femur bone is performed. Those parameters include natural frequencies, mode shapes, principal normal stress distributions, principal shear stress distributions, maximum shear elastic strains and total deformation. These parameters reflect an idea about behavior of the femur bone under actual loading conditions. This analysis enables an implant designer to focus on material properties and strength considerations of the implants which are to be used in case of bone damage.

Details

World Journal of Engineering, vol. 14 no. 3
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 16 March 2015

Yingping Hong, Ting Liang, Pinggang Jia, Wenyi Liu, Qiulin Tan, Chen Li, Tingli Zheng, Binger Ge and Jijun Xiong

Physical contact and traditional sensitive structure Physical contact and traditional pressure-sensitive structures typically do not operate well in harsh environments…

Abstract

Purpose

Physical contact and traditional sensitive structure Physical contact and traditional pressure-sensitive structures typically do not operate well in harsh environments. This paper proposes a high-temperature pressure measurement system for wireless passive pressure sensors on the basis of inductively coupled LC resonant circuits.

Design/methodology/approach

This paper begins with a general introduction to the high-temperature pressure measurement system, which consists of a reader antenna inductively coupled to the sensor circuit, a readout unit and a heat insulation unit. The design and fabrication of the proposed measurement system are then described in detail.

Findings

A wireless passive pressure sensor without an air channel is fabricated using high-temperature co-fired ceramics (HTCC) technology and its signal is measured by the designed measurement system. The designed heat insulation unit keeps the reader antenna in a safe environment of 159.5°C when the passive sensor is located in a 900°C high-temperature zone continuously for 0.5 h. The proposed system can effectively detect the sensor’s resonance frequency variation in a high bandwidth from 1 to 100 MHz with a frequency resolution of 0.006 MHz, tested from room temperature to 500°C for 30 min.

Originality/value

Expensive and bulky equipment (impedance analyzers or network analyzers) restrict the use of the readout method outside the laboratory environment. This paper shows that a novel readout circuit can replace the laboratory equipment to demodulate the measured pressure by extracting the various sensors’ resonant frequency. The proposed measurement system realizes automatic and continuous pressure monitoring in a high-temperature environment with a coupled distance of 2.5 cm. The research finding is meaningful for the measurement of passive pressure sensors under a wide temperature range.

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Book part
Publication date: 11 May 2007

Austin Troy and Roger G. Kennedy

This book is divided into four parts: (1) Institutions and policy, (2) The economics of hazards, (3) Community involvement, and (4) Management and ecology. The first…

Abstract

This book is divided into four parts: (1) Institutions and policy, (2) The economics of hazards, (3) Community involvement, and (4) Management and ecology. The first section contains four chapters that cover the issue of wildfire from historical and institutional perspectives. “Forest fire history: learning from disaster” by Roger Kennedy (Chapter 2) addresses the pressures and politics giving rise to the current situation. “Fire Policy in the Urban–Wildland Interface in the United States: What are the Issues and Possible Solutions?” (Chapter 3) by Scott Stephens and Brandon Collins provides a summary of the problems associated with wildfire hazards in UWI communities, discusses fuels-treatment options for local governments and property owners, and analyzes challenges to planning, drawing on experiences from Australia. “Wildfire hazard mitigation as “safe” smart growth” (Chapter 4) by Robert Paterson looks at how smart growth principals are being adapted to fire-safe land use planning and zoning, including a discussion of the role of regional coordination and state-level planning requirements. “Practical and institutional constraints on adopting wide-scale prescribed burning: lessons from the mountains of California” (Chapter 5) by Kurt Menning details the problems of fuel accumulation due to suppression, the potential power of prescribed burning as a management tool, and the social and regulatory obstacles to implementing wide-scale prescribed burning programs.

Details

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

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Article
Publication date: 9 November 2012

Hendrik Kolbe, Annette Muetze and Kay Hameyer

The purpose of this paper is to contribute toward the modelling of the microscopic interaction between high‐frequency discharge bearing currents and rolling element…

Abstract

Purpose

The purpose of this paper is to contribute toward the modelling of the microscopic interaction between high‐frequency discharge bearing currents and rolling element bearings in the contact zone. It also aims to develop a reduced model that can serve as a starting point for further developments.

Design/methodology/approach

The complexity of an ideal comprehensive model is identified and analysed. Based thereon, a reduced model is developed.

Findings

The true system is highly complex and cannot be solved in a single‐step approach. The proposed reduced model allows the explanation of the melting of the bearing surfaces under the influence of the high‐frequency currents. It also provides a starting point for the development of an extended model.

Research limitations/implications

The model excludes the dynamic rolling movement of the bearing. The development of the frosting and fluting observed on the bearing running surfaces can only be explained in parts.

Practical implications

The melting of the bearing race surface can be modelled and thereby explained. The proposed model forms a good basis for further work toward an extended model to explain the high‐frequency bearing current bearing damage mechanism.

Originality/value

The paper offers a method to model the microscopic interaction between high‐frequency discharge bearing currents and rolling element bearings in the contact zone. This phenomenon has not yet been modelled to this extent. Such a model – and the understanding brought forth from it – allows the reduction in the cost for safe operation of modern variable speed drive systems.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 18 October 2011

Jungguk Kim, Agus Budiyono, Dong‐Min Kim, Ho‐Geun Song and Doo‐Hyun Kim

The purpose of this paper is to introduce a new danger‐aware Operational Flight Program (OFP) for the unmanned helicopter's auto‐navigation based on the well‐known…

Abstract

Purpose

The purpose of this paper is to introduce a new danger‐aware Operational Flight Program (OFP) for the unmanned helicopter's auto‐navigation based on the well‐known time‐triggered message‐triggered object (TMO) model.

Design/methodology/approach

In this design with the TMO, the danger‐awareness means two things. First, an unmanned helicopter maneuvers on safe altitudes to avoid buildings or mountains when navigating to the target position. It is assumed that minimum safe altitudes are given on evenly spaced grids and on the center points of every four adjacent grids. A three‐dimensional (3D) path‐finding algorithm using this safe‐altitude information is proposed. Second, a helicopter automatically avoids a zone with very high temperature caused by a fire.

Findings

Since the auto‐flight control system requires componentized real‐time processing of sensors and controllers, the TMO model that has periodic and sporadic threads as members, has been used in designing the OFP. It has been found that using the TMO scheme is a way to construct a very flexible, well‐componentized and timeliness‐guaranteed OFP.

Practical implications

As the RTOS, RT‐eCos has been used. It was developed a few years ago based on the eCos3.0 to support the real‐time thread model of the TMO scheme. To verify this navigation system, a hardware‐in‐the‐loop simulation (HILS) system also has been developed.

Originality/value

Designing an OFP by using the real‐time object model TMO and the proposed 3D safe path finding algorithm is a whole new effective deadline‐based approach. And the developed OFP can be used intensively in the phase of disaster response and recovery.

Details

Aircraft Engineering and Aerospace Technology, vol. 83 no. 6
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 7 November 2016

Fahim Ullah, Bilal Ayub, Siddra Qayyum Siddiqui and Muhammad Jamaluddin Thaheem

The purpose of this paper is to investigate the critical decision factors of public–private partnership (PPP) concession which is complex due to a number of uncertain and…

Abstract

Purpose

The purpose of this paper is to investigate the critical decision factors of public–private partnership (PPP) concession which is complex due to a number of uncertain and random variables. To identify critical factors contributing to determination of concession period, this study reviews the published literature. It also identifies countries contributing most in PPP research. As a whole, it provides a mutually beneficial scenario by formulating a decision-making matrix.

Design/methodology/approach

This paper reviews the literature published during the period 2005-2015. A two-staged methodology is followed on retrieved scholarly papers: first, countries contributing to PPP are identified along with authors and affiliated institutions. Second, using frequency analysis of shortlisted critical factors, yearly appearance and stakeholders affected, a decision matrix is formulated.

Findings

The most contributing country toward PPP research is China, followed by the USA both in terms of country- and author-based contribution. In total, 63 factors are identified that affect PPP concession out of which, 8 per cent are highly critical and 21 per cent are marginally critical for decision-making.

Practical implications

Critical factors of PPP concession period will be identified with the help of decision-making matrix. This will help in adequate resource allocation for handling critical factors ensuring project success. Researchers may also understand the research trends in the past decade to usher ways for future improvements.

Originality/value

This paper reports findings of an original and innovative study, which identifies critical success factors of PPP concession period and synthesizes them into a decision-making matrix. Many of the previous studies have identified and ranked the critical factors but such a synthesis has not been reported.

Details

Journal of Financial Management of Property and Construction, vol. 21 no. 3
Type: Research Article
ISSN: 1366-4387

Keywords

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Article
Publication date: 1 March 2003

A. Babini, R. Borsari, A. Fontanini, F. Dughiero and M. Forzan

In the paper a 3D finite element method (FEM) model of induction sealing of multilayer packaging material will be presented. A parametrical analysis of the model has been…

Abstract

In the paper a 3D finite element method (FEM) model of induction sealing of multilayer packaging material will be presented. A parametrical analysis of the model has been performed in order to evaluate the behaviour of the system as regards the power supply frequency and insertion of high permeability materials in particular zones of the inductor. Some considerations about the difficulty of implementing the FEM model will be discussed. A comparison with experimental results has been done in order to understand the reliability of the numerical model.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 22 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

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Abstract

Details

The Handbook of Road Safety Measures
Type: Book
ISBN: 978-1-84855-250-0

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Book part
Publication date: 20 June 2017

David Shinar

Abstract

Details

Traffic Safety and Human Behavior
Type: Book
ISBN: 978-1-78635-222-4

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Abstract

Details

Automated Information Retrieval: Theory and Methods
Type: Book
ISBN: 978-0-12266-170-9

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