Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Selected Works

PDF

Analysis

Articles 1 - 30 of 51

Full-Text Articles in Physical Sciences and Mathematics

Pathway Variation Analysis (Pva): Modelling And Simulations, Nagesh Shukla, Sudi Lahiri, Darek Ceglarek Nov 2015

Pathway Variation Analysis (Pva): Modelling And Simulations, Nagesh Shukla, Sudi Lahiri, Darek Ceglarek

Nagesh Shukla

Maintaining a care pathway within a hospital to provide complex care to patients is associated with challenges related to variations from the pathway. This occurs due to ineffective decision-making processes, unclear process steps, the interactions, conflicting performance measures for speciality units, and the availability of resources. These variations from the care pathway or standard care delivery processes lead to longer patient waiting times and lower patient throughput. Traditional approaches to improve the pathway focus primarily on reducing variations within the care pathway such as bottlenecks or throughput within the pathway rather than examining variations from the care pathway. In this …

Go to article

Data-Driven Modeling And Analysis Of Household Travel Mode Choice, Nagesh Shukla, Jun Ma, Rohan Wickramasuriya Denagamage, Nam N. Huynh Apr 2015

Data-Driven Modeling And Analysis Of Household Travel Mode Choice, Nagesh Shukla, Jun Ma, Rohan Wickramasuriya Denagamage, Nam N. Huynh

Nagesh Shukla

One of the important problems studied in the area of travel behavior analysis is travel mode choice which is one of the four crucial steps in transportation demand estimation for urban planning. State of the art models in travel demand modelling can be classified as trip based; tour based; and activity based. In trip based approach, each individual trips is modelled as independent and isolated trips i.e. no connections between different trips. In tour based approach, trips that start and end from the same location (home, work, etc) and trips within a tour are dependent on each other. In past …

Go to article

Using Social Network Analysis To Evaluate Health - Related Adaptation Decision Making In Cambodia, Kathryn Bowen, Damon Alexander, Fiona Miller, Dany Va Mar 2014

Using Social Network Analysis To Evaluate Health - Related Adaptation Decision Making In Cambodia, Kathryn Bowen, Damon Alexander, Fiona Miller, Dany Va

Dany Va

Climate change adaptation in the health sector requires decisions across sectors, levels of government, and organisations. The networks that link these different institutions, and the relationships among people within these networks, are therefore critical influences on the nature of adaptive responses to climate change in the health sector. This study uses social network research to identify key organisational players engaged in developing health-related adaptation activities in Cambodia. It finds that strong partnerships are reported as developing across sectors and different types of organisations in relation to the health risks from climate change. Government ministries are influential organisations, whereas donors, development …

Go to article

Critical Phenomena And Estimation Of The Spontaneous Magnetization By A Magnetic Entropy Analysis In Mn0.96nb0.04coge Alloy, Jyotish C. Debnath, A M. Strydom, P Shamba, Jianli Wang, S X. Dou Mar 2014

Critical Phenomena And Estimation Of The Spontaneous Magnetization By A Magnetic Entropy Analysis In Mn0.96nb0.04coge Alloy, Jyotish C. Debnath, A M. Strydom, P Shamba, Jianli Wang, S X. Dou

Shi Xue Dou

Magnetic and magnetocaloric properties of the alloy Mn0.96Nb0.04CoGe have been investigated.

Go to article

Monitoring People Using Location-Based Social Networking And Its Negative Impact On Trust: An Exploratory Contextual Analysis Of Five Types Of "Friend" Relationships, Sarah Jean Fusco, Katina Michael, Anas Aloudat, Roba Abbas Mar 2014

Monitoring People Using Location-Based Social Networking And Its Negative Impact On Trust: An Exploratory Contextual Analysis Of Five Types Of "Friend" Relationships, Sarah Jean Fusco, Katina Michael, Anas Aloudat, Roba Abbas

Professor Katina Michael

Location based social networking (LBSN) applications are part of a new suite of social networking tools. LBSN is the convergence between location based services (LBS) and online social networking (OSN). LBSN applications offer users the ability to look up the location of another “friend” remotely using a smart phone, desktop or other device, anytime and anywhere. Users invite their friends to participate in LBSN and there is a process of consent that follows. This paper explores the potential impact of LBSN upon trust in society. It looks at the willingness of individuals to share their location data with family, friends, …

Go to article

Doing Discourse Analysis, Gordon R. Waitt Jul 2013

Doing Discourse Analysis, Gordon R. Waitt

Gordon Waitt

My hope in writing this chapter is to generate enthusiasm for geographical research employing discourse analysis. My intention is to provide some advice on doing discourse analysis to facilitale the design of research. I first outline why some geographers have been inspired by this approach. I suggest how Foucauldian discourse analysis is a break from other critical methods applied to textual analysis, including content analysis, semiology, and iconography. The theoretical underpinnings of the method provided by Michel Foucault, a French poststructuralist philosopher, is a key source of difference. I therefore condense Michel Foucault's contribution to discourse analysis by sketching out …

Go to article

Intergrain Connectivity Of Mgb2 Ceramics Studied By Impedance Analysis, C.C Wang, C Wang, Rong Zeng, S X. Dou Jun 2013

Intergrain Connectivity Of Mgb2 Ceramics Studied By Impedance Analysis, C.C Wang, C Wang, Rong Zeng, S X. Dou

Shi Xue Dou

First, by using of the conventional Rowell analysis, we demonstrated that the addition of nano BN particles can effectively eliminate MgO and pores in MgB2 resulting in a very high density and good connectivity of BN-doped MgB2. Then, another method—low-frequency dielectric impedance analysis—was introduced to characterize the properties of the grain boundaries of MgB2. A comparative impedance study was performed in the frequency range from 100 Hz to 100 MHz on pure and nano BN-doped MgB2. The study revealed some following interesting results: (1) a dielectric resonance around frequency of 108 in both samples was observed, which was argued to …

Go to article

Wearable Technology For The Real-Time Analysis Of Sweat During Exercise, D Morris, B Schazmann, Y Wu, C Fay, Stephen T. Beirne, C Slater, King-Tong Lau, Gordon G. Wallace, Dermot Diamond Mar 2013

Wearable Technology For The Real-Time Analysis Of Sweat During Exercise, D Morris, B Schazmann, Y Wu, C Fay, Stephen T. Beirne, C Slater, King-Tong Lau, Gordon G. Wallace, Dermot Diamond

Gordon Wallace

-Textile based sensors which can be used to measure the chemical composition of bodily fluids represents a major advancement in the area of wearable technology. BIOTEX is an EU funded project aiming to develop such sensors with a particular interest in monitoring perspiration. A textile based fluid handling system has been developed for sample collection and transport. Sodium, conductivity and pH sensors have also been developed. This paper details the integration and testing of these sensors. Results show that the developed system can collect and analyze sweat in real time during exercise and transmit this data wirelessly to a remote …

Go to article

Texture Analysis Using Partially Ordered Markov Models, Jennifer Davidson, Ashit Talukder, Noel A. Cressie Feb 2013

Texture Analysis Using Partially Ordered Markov Models, Jennifer Davidson, Ashit Talukder, Noel A. Cressie

Professor Noel Cressie

Texture is a phenomenon in image data that continues to receive wide-spread interest due to its broad range of applications. The paper focuses on but one of several ways to model textures, namely, the class of stochastic texture models. the authors introduce a new spatial stochastic model called partially ordered Markov models, or POMMs. They show how POMMs are a generalization of a class of models called Markov mesh models, or MMMs, that allow an explicit closed form of the joint probability, just as do MMMs. While POMMs are a type of Markov random field model (MRF), the general MRFs …

Go to article

A Spatial Analysis Of Multivariate Output From Regional Climate Models, Stephan Sain, Reinhard Furrer, Noel A. Cressie Feb 2013

A Spatial Analysis Of Multivariate Output From Regional Climate Models, Stephan Sain, Reinhard Furrer, Noel A. Cressie

Professor Noel Cressie

Climate models have become an important tool in the study of climate and climate change, and ensemble experiments consisting of multiple climate-model runs are used in studying and quantifying the uncertainty in climate-model output. However, there are often only a limited number of model runs available for a particular experiment, and one of the statistical challenges is to characterize the distribution of the model output. To that end, we have developed a multivariate hierarchical approach, at the heart of which is a new representation of a multivariate Markov random field. This approach allows for flexible modeling of the multivariate spatial …

Go to article

A Spatial Analysis Of Variance Applied To Soil-Water Infiltration, C Gotway, Noel A. Cressie Feb 2013

A Spatial Analysis Of Variance Applied To Soil-Water Infiltration, C Gotway, Noel A. Cressie

Professor Noel Cressie

A spatial analysis of variance uses the spatial dependence among the observations to modify the usual interference procedures associated with a statistical linear model. When spatial correlation is present, the usual tests for presence of treatment effects may no longer be valid, and erroneous conclusions may result from assuming that the usual F ratios are F distributed. This is demonstrated using a spatial analysis of soil-water infiltration data. Emphasis is placed on modeling the spatial dependence structure with geostatistical techniques, and this spatial dependence structure is then used to test hypotheses about fixed effects using a nested linear model. -Authors

Go to article

Bayesian Hierarchical Analysis Of Minefield Data, Noel A. Cressie, Andrew B. Lawson Feb 2013

Bayesian Hierarchical Analysis Of Minefield Data, Noel A. Cressie, Andrew B. Lawson

Professor Noel Cressie

Based on remote sensing of a potential minefield, point locations are identified, some of which may not be mines. The mines and mine-like objects are to be distinguished based on their point patterns, although it must be emphasized that all we see is the superposition of their locations. In this paper, we construct a hierarchical spatial point-process model that accounts for the different patterns of mines and mine-like objects and uses posterior analysis to distinguish between them. Our Bayesian approach is applied to COBRA image data obtained from the NSWC Coastal Systems Station, Dahlgren Division, Panama City, Florida. 2003 Copyright …

Go to article

A Robust-Resistant Spatial Analysis Of Soil Water Infiltration., Noel A. Cressie, R Horton Feb 2013

A Robust-Resistant Spatial Analysis Of Soil Water Infiltration., Noel A. Cressie, R Horton

Professor Noel Cressie

Concentrates on estimating the spatial correlations between soil water infiltration observations, with special emphasis on resistant methods to remove nonstationarity. After this removal, robust semivariogram estimators are used to examine the spatial dependencies for various tillage treatments. There is some indication that infiltration characteristics inherit different types of spatial dependency, depending on the tillage treatment applied.-from Authors

Go to article

Location And Tracking Of Mobile Devices: Überveillance Stalks The Streets, Katina Michael, Roger Clarke Dec 2012

Location And Tracking Of Mobile Devices: Überveillance Stalks The Streets, Katina Michael, Roger Clarke

Professor Katina Michael

During the last decade, location-tracking and monitoring applications have proliferated, in mobile cellular and wireless data networks, and through self-reporting by applications running in smartphones that are equipped with onboard global positioning system (GPS) chipsets. It is now possible to locate a smartphone-user's location not merely to a cell, but to a small area within it. Innovators have been quick to capitalise on these location-based technologies for commercial purposes, and have gained access to a great deal of sensitive personal data in the process. In addition, law enforcement utilise these technologies, can do so inexpensively and hence can track many …

Go to article

A Mathematical Model For The Biological Treatment Of Industrial Wastewater In A Reactor Cascade, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy Dec 2012

A Mathematical Model For The Biological Treatment Of Industrial Wastewater In A Reactor Cascade, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy

Associate Professor Annette Worthy

Many industrial processes, particularly in the food industry, produce slurries or wastewaters containing high concentrations of biodegradable organic materials. Before these contaminated wastewaters can be discharged the concentration of the biodegradable organic pollutant must be reduced. One way to do this is to pass the wastewater through a bioreactor containing biomass which grows through consumption of the pollutant. Anaerobic conditions are often favoured for the processing of waste materials with high levels of biodegradable organic pollutants as these can be removed with low investment and operational costs. We investigate the steady state effluent concentration leaving a cascade of two reactors. …

Go to article

Towards Knowledge Management In Sports Event Management: Context Analysis Of Malaysian Biannual Games With Commonkads, Azizul Rahman Abdul Ghaffar, Ghassan Beydoun, Jun Shen, William Tibben Dec 2012

Towards Knowledge Management In Sports Event Management: Context Analysis Of Malaysian Biannual Games With Commonkads, Azizul Rahman Abdul Ghaffar, Ghassan Beydoun, Jun Shen, William Tibben

Dr William Tibben

Context Analysis (CA) is typically used as an early phase preceding the development of a knowledge-based systems in order to indicate how the system should interact with its environment and the various stakeholders. We undertake a detailed context analysis of business processes of the Malaysian Games (MG)to highlight blind spots of the process and enable the identification of an initial sports event knowledge management (KM) framework. Firstly, our CommonKADS driven analysis highlights how we can improve the business process and enable the organization to develop, distribute and apply its knowledge resources effectively. Secondly, the paper highlights specific features about the …

Go to article

Power Quality Survey Factor Analysis Using Multivariable Linear Regression (Mvlr), Chandana Herath, Victor J. Gosbell, Sarath Perera, David A. Stirling Dec 2012

Power Quality Survey Factor Analysis Using Multivariable Linear Regression (Mvlr), Chandana Herath, Victor J. Gosbell, Sarath Perera, David A. Stirling

Dr David Stirling

During the past two decades, there has been a considerable number of Power Quality (PQ) monitoring programs completed throughout the world. The information collected during these surveys can provide a detailed picture of the expected electrical environment help utilities to plan their future networks in relation to power quality performance. The mass of data gathered for a sample of sites of a large-scale power quality (PQ) survey of this nature has the potential to reveal good and bad influences on power quality if an appropriate procedure for analysis can be determined. If it is known which characteristics are more important …

Go to article

Power Quality Data Analysis Using Unsupervised Data Mining, Ali Asheibi, David A. Stirling, Sarath Perera, D A. Robinson Dec 2012

Power Quality Data Analysis Using Unsupervised Data Mining, Ali Asheibi, David A. Stirling, Sarath Perera, D A. Robinson

Dr David Stirling

The rapid increase in the size of databases required to store power quality monitoring data has demanded new techniques for analysing and understanding the data. One suggested technique to assist in analysis is data mining. Data mining is a process that uses a variety of data analysis tools to identify hidden patterns and relationships within large samples of data. This paper presents several data mining tools and techniques that are applicable to power quality data analysis to enable efficient reporting of disturbance indices and identify network problems through pattern recognition. This paper also presents results of data mining techniques applied …

Go to article

Power Quality Data Analysis Using Unsupervised Data Mining, Ali Asheibi, David A. Stirling, Sarath Perera, D A. Robinson Dec 2012

Power Quality Data Analysis Using Unsupervised Data Mining, Ali Asheibi, David A. Stirling, Sarath Perera, D A. Robinson

Dr Duane Robinson

The rapid increase in the size of databases required to store power quality monitoring data has demanded new techniques for analysing and understanding the data. One suggested technique to assist in analysis is data mining. Data mining is a process that uses a variety of data analysis tools to identify hidden patterns and relationships within large samples of data. This paper presents several data mining tools and techniques that are applicable to power quality data analysis to enable efficient reporting of disturbance indices and identify network problems through pattern recognition. This paper also presents results of data mining techniques applied …

Go to article

Kinetic Analysis Of Oleic Acid Esterification Using Lipolytic Enzyme As Catalyst, Mohd S. Mahmud, James W. Ryan, Cyrus Cooper, Tomasz Safinski, Mark I. Nelson, Harvinder S. Sidhu, Soji A. Adesina Dec 2012

Kinetic Analysis Of Oleic Acid Esterification Using Lipolytic Enzyme As Catalyst, Mohd S. Mahmud, James W. Ryan, Cyrus Cooper, Tomasz Safinski, Mark I. Nelson, Harvinder S. Sidhu, Soji A. Adesina

Associate Professor Mark Nelson

This paper deals with the esterification kinetics of oleic acid (OA) using ethanol (EtOH) over acrylic-supported lipase from Aspergillus niger (Novozym 435) as catalyst. The reaction was carried out in a stirred 500 mL Pyrex glass reactor at 45oC under conditions with negligible external and internal transport resistances. Reaction runs in a microaqueous medium employed OA: EtOH ratio, b, between 0.01 to 2.0 without initial addition of water. The rate dependency on reactant concentration has a maximum at b=0.9, just below the stoichiometric ratio, and was therefore described by a Michaelis- Menten kinetic expression implicating irreversible surface reaction between adsorbed …

Go to article

Autoignition Of Hydrocarbons In A Batch Reactor: Analysis Of A Reduced Model, Mark I. Nelson, E Balakrishnan Dec 2012

Autoignition Of Hydrocarbons In A Batch Reactor: Analysis Of A Reduced Model, Mark I. Nelson, E Balakrishnan

Associate Professor Mark Nelson

n the late 1960s Gray and Yang developed the first reduced kinetic model for the oxidation of hydrocarbon fuels that qualitatively described many features observed experimentally. Since then a number of reduced kinetic models have been proposed in the literature. In this contribution we analyse the steady-state behaviour of one such scheme. The chemical component of the model contains four chemical species undergoing six reactions. By making a pool-chemical approximation this system is reduced to three coupled non-linear differential equations: a temperature equation and equations for two reactive chemical intermediates. It is shown that any steady-state solution of this model …

Go to article

A Fundamental Analysis Of Continuous Flow Bioreactor And Membrane Reactor Models With Non-Competitive Product Inhibition. Iii. Linear Inhibition, Mark I. Nelson, Wei X. Lim Dec 2012

A Fundamental Analysis Of Continuous Flow Bioreactor And Membrane Reactor Models With Non-Competitive Product Inhibition. Iii. Linear Inhibition, Mark I. Nelson, Wei X. Lim

Associate Professor Mark Nelson

The steady-state production of a product produced through the growth of microorganisms in a continuous flow bioreactor is presented. A generalised reactor model is used in which both the classic well-stirred bioreactor and the idealised membrane bioreactor are considered as special cases. The reaction is assumed to be governed by Monod growth kinetics subject to non-competitive product inhibition. Inhibition is modelled as a decreasing linear function of the product concentration with a finite cut-off. This reaction scheme is well documented in the literature, although a stability analysis of the governing equations has not previously been presented. The steady-state solutions for …

Go to article

Towards Knowledge Management In Sports Event Management: Context Analysis Of Malaysian Biannual Games With Commonkads, Azizul Rahman Abdul Ghaffar, Ghassan Beydoun, Jun Shen, William Tibben Dec 2012

Towards Knowledge Management In Sports Event Management: Context Analysis Of Malaysian Biannual Games With Commonkads, Azizul Rahman Abdul Ghaffar, Ghassan Beydoun, Jun Shen, William Tibben

Associate Professor Ghassan Beydoun

Context Analysis (CA) is typically used as an early phase preceding the development of a knowledge-based systems in order to indicate how the system should interact with its environment and the various stakeholders. We undertake a detailed context analysis of business processes of the Malaysian Games (MG)to highlight blind spots of the process and enable the identification of an initial sports event knowledge management (KM) framework. Firstly, our CommonKADS driven analysis highlights how we can improve the business process and enable the organization to develop, distribute and apply its knowledge resources effectively. Secondly, the paper highlights specific features about the …

Go to article

Dynamic Modelling Of Hydroelectric Turbine-Generator Unit Connected To A Hvdc System For Small Signal Stability Analysis, Yin Chin Choo, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, Michael Negnevitsky Dec 2012

Dynamic Modelling Of Hydroelectric Turbine-Generator Unit Connected To A Hvdc System For Small Signal Stability Analysis, Yin Chin Choo, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, Michael Negnevitsky

Dr Ashish Agalgaonkar

This paper presents the linearised small-signal dynamic modelling of hydroelectric turbine-generator (TG) unit with CIGRE first high-voltage direct current (HVDC) benchmark system in the synchronously rotating D-Q reference frame for small-signal stability analysis. The interaction behaviour between the hydroelectric unit and the dynamics and control of HVDC system is investigated utilising eigen-analysis,participation factor analysis and by conducting sensitivity studies. The computation of eigenvalues and eigenvectors for small signal stability analysis provides an invaluable insight onto the power system dynamic behaviour by characterising the damping and frequency of the system oscillatory modes. Theconsequences of different operating conditions, such as active and …

Go to article

The Fourier Spectrum Analysis Of Optical Feedback Self-Mixing Signal Under Weak And Moderate Feedback, Xiaojun Zhang, Jiangtao Xi, Yanguang Yu, Joe F. Chicharo Dec 2012

The Fourier Spectrum Analysis Of Optical Feedback Self-Mixing Signal Under Weak And Moderate Feedback, Xiaojun Zhang, Jiangtao Xi, Yanguang Yu, Joe F. Chicharo

Dr Yanguang Yu

The spectrum characteristics of self-mixing signals observed in optical feedback self-mixing interferometry (OFSMI) is studied in this paper. The purpose is to provide guidance for the design of pre-processing techniques for eliminating noise or disturbance. The influence of two important parameters of the OFSMI system on the spectrum, that is, the optical feedback factor and the linewidth enhancment factor, are measured by means of Discrete Fourier transform (DFT). The simulated results show that, at a weak feedback, the OFSMI signals are strictly band limited in nature, with the cut-off frequencies being the vibration frequency and the fringe frequency respectively. Also …

Go to article

Online Grocery Systems Design Through Task Analysis, Mark Freeman, Alison Freeman Dec 2012

Online Grocery Systems Design Through Task Analysis, Mark Freeman, Alison Freeman

Dr Mark Freeman

Purpose – Modelling users’ interactions online is envisaged to allow developers to increase the usability of online systems and will aid system developers in building better systems to meet users’ needs, hereby creating better system design processes. Design/methodology/approach – The normative task model that was developed in this paper was created through an expert review of 14 online grocery stores, using a reverse engineering technique to model the features of the stores’ ordering process. Findings – The research identified three main areas of user experience when undertaking the process of adding a product to an online trolley: attempting to retrieve …

Go to article

Molecular Dynamics Analysis Of Apolipoprotein-D - Lipid Hydroperoxide Interactions: Mechanism For Selective Oxidation Of Met-93, Aaron J. Oakley, Surabhi Bhatia, Heath Ecroyd, Brett Garner Dec 2012

Molecular Dynamics Analysis Of Apolipoprotein-D - Lipid Hydroperoxide Interactions: Mechanism For Selective Oxidation Of Met-93, Aaron J. Oakley, Surabhi Bhatia, Heath Ecroyd, Brett Garner

Heath Ecroyd

Background: Recent studies suggest reduction of radical-propagating fatty acid hydroperoxides to inert hydroxides by interaction with apolipoprotein-D (apoD) Met93 may represent an antioxidant function for apoD. The nature and structural consequences of this selective interaction are unknown. Methodology/Principal Findings: Herein we used molecular dynamics (MD) analysis to address these issues. Longtimescale simulations of apoD suggest lipid molecules are bound flexibly, with the molecules free to explore multiple conformations in a binding site at the entrance to the classical lipocalin ligand-binding pocket. Models of 5s- 12s- and 15s hydroperoxyeicosatetraenoic acids were created and the lipids found to wrap around Met93 thus …

Go to article

Fault Analysis Of The Katan Family Of Block Ciphers, Shekh Faisal Abdul-Latip, Mohammad Reza Reyhanitabar, Willy Susilo, Jennifer Seberry Dec 2012

Fault Analysis Of The Katan Family Of Block Ciphers, Shekh Faisal Abdul-Latip, Mohammad Reza Reyhanitabar, Willy Susilo, Jennifer Seberry

Professor Willy Susilo

In this paper, we investigate security of the KATAN family of block ciphers against differential fault attacks. KATAN consists of three variants with 32, 48 and 64-bit block sizes, called KATAN32, KATAN48 and KATAN64, respectively. All three variants have the same key length of 80 bits. We assume a single-bit fault injection model where the adversary is supposed to be able to corrupt a single random bit of the internal state of the cipher and this fault induction process can be repeated (by resetting the cipher); i.e., the faults are transient rather than permanent. First, we show how to identify …

Go to article

Security Analysis Of Michael: The Ieee 802.11i Message Integrity Code, Jianyong Huang, Jennifer Seberry, Willy Susilo, Martin W. Bunder Dec 2012

Security Analysis Of Michael: The Ieee 802.11i Message Integrity Code, Jianyong Huang, Jennifer Seberry, Willy Susilo, Martin W. Bunder

Professor Willy Susilo

The latest IEEE 802.11i uses a keyed hash function, called Michael, as the message integrity code. This paper describes some properties and weaknesses of Michael. We provide a necessary and sufficient condition for finding collisions of Michael. Our observation reveals that the collision status of Michael only depends on the second last block message and the output of the block function in the third last round. We show that Michael is not collision-free by providing a method to find collisions of this keyed hash function. Moreover, we develop a method to find fixed points of Michael. If the output of …

Go to article

Fault Analysis Of The Katan Family Of Block Ciphers, Shekh Faisal Abdul-Latip, Mohammad Reza Reyhanitabar, Willy Susilo, Jennifer Seberry Dec 2012

Fault Analysis Of The Katan Family Of Block Ciphers, Shekh Faisal Abdul-Latip, Mohammad Reza Reyhanitabar, Willy Susilo, Jennifer Seberry

Dr Reza Reyhanitabar

In this paper, we investigate security of the KATAN family of block ciphers against differential fault attacks. KATAN consists of three variants with 32, 48 and 64-bit block sizes, called KATAN32, KATAN48 and KATAN64, respectively. All three variants have the same key length of 80 bits. We assume a single-bit fault injection model where the adversary is supposed to be able to corrupt a single random bit of the internal state of the cipher and this fault induction process can be repeated (by resetting the cipher); i.e., the faults are transient rather than permanent. First, we show how to identify …

Go to article

Next Last