Physical Sciences and Mathematics Commons^™

Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy

Dr Deogratias Harorimana

ICT for Poverty Alleviation in Pacific Island Nations: Study of ICTs4D in Fiji There has been a vague and little knowledge on the role or potential of Information and Communications Technologies (ICTs) in relation to addressing poverty in Fiji. This may be probably due to the newness of the technology in the South Pacific Region as a whole but also probably due to the fact that only 9.7% of the current Fiji 931,000 populations are internet users (ITC Figures 2011). This paper reports on finding how ICTs is contributing towards poverty alleviation in Fiji. On the basis of reviewed best …

Terrain Constrained Stereo Correspondence, Gabrielle Inglis, Chris Roman

Christopher N. Roman

There is a persistent need in the oceanographic community for accurate three dimensional reconstructions of seafloor structures. To meet this need underwater mapping techniques have expanded to include the use of stereo vision and high frequency multibeam sonar for mapping scenes 10's to 100's of square meters in size. Both techniques have relative advantages and disadvantages that depend on the task at hand and the desired accuracy. In this paper, we develop a method to constrain the often problematic stereo correspondence search to small sections of the image that correspond to estimated ranges along the epipolar lines calculated from coregistered …

Application Of Structured Light Imaging For High Resolution Mapping Of Underwater Archaeological Sites, Chris Roman, Gabrielle Inglis, James Rutter

Christopher N. Roman

This paper presents results from recent work using structured light laser profile imaging to create high resolution bathymetric maps of underwater archaeological sites. Documenting the texture and structure of submerged sites is a difficult task and many applicable acoustic and photographic mapping techniques have recently emerged. This effort was completed to evaluate laser profile imaging in comparison to stereo imaging and high frequency multibeam mapping. A ROV mounted camera and inclined 532 nm sheet laser were used to create profiles of the bottom that were then merged into maps using platform navigation data. These initial results show very promising resolution …

An Estate Dilemma - Inaccessible Assets Hiding Behind Passwords And Encryption, Douglas J. Henderson

DOUGLAS J HENDERSON

Every person living in the modern world holds valuable assets, data, or information in digital mediums. Digital mediums include not only digital hardware storage mediums in personal possession (like external hard drives and internal hard drives within laptop and desktop computers, personal digital assistants, cell phones, and the like), but also those only accessible through a network. Because so much is held in digital mediums, when an individual dies or becomes incapacitated, another person must know how to access the incapacitated person’s digital assets and other important information (this person is known herein as the ‘Responsible Party’). There are potential …

Performance Of Java Middleware - Java Rmi, Jaxrpc, And Corba, N. A. B. Gray

Associate Professor Neil Gray

Developers of distributed Java systems can now choose among Java-RMI, CORBA, and Web-Service (JAXRPC) middleware technologies. Performance is one factor that has to be considered in choosing the appropriate technology for a particular application. The results presented in this paper show that the nature of response data has a greater impact on relative performance than has been allowed for in most previous studies. Relative performances of the technologies as measured on simple requests and responses are not representative of the behaviour that can be expected in practical applications.

Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Dr Guilin Wang

In a (t, n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. In this article, we discuss the implementation and comparison of some threshold proxy signature schemes that are based on the RSA cryptosystem. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et …

Proxy Signature Scheme With Multiple Original Signers For Wireless E-Commerce Applications, Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Dr Guilin Wang

In a proxy signature scheme, a user delegates his/her signing capability to another user in such a way that the latter can sign messages on behalf of the former. We propose an efficient and secure proxy signature scheme with multiple original signers. Our scheme is suitable for wireless electronic commerce applications, since the overheads of computation and communication are low. As an example, we present an electronic air ticket booking scheme for wireless customers.

Diseñando Colisiones De Satélites En La Guerra Cibernética Encubierta, Jan Kallberg

Jan Kallberg

La guerra concentrada en la red depende de la red de información global para capacidades de combate conjuntas.3 La capa fundamental crea la capacidad de combate global como la columna vertebral espacial de la red de información donde los haberes espaciales son el elemento decisivo. EE.UU. depende de las capacidades espaciales para su éxito y la seguridad nacional de EE.UU. se basa hoy en día en un número limitado de satélites muy utilizados. Estos satélites son cruciales para la disuasión estratégica, la vigilancia, la recopilación de inteligencia y las comunicaciones militares. Si la disuasión estratégica falla, los satélites forman parte …

Contextual Effects In Modeling For Small Domain Estimation, Mohammad-Reza Namazi-Rad, David G. Steel

Professor David Steel

Many different Small Area Estimation (SAE) methods have been proposed to overcome the challenge of findingreliable estimates for small domains. Often, the required data for various research purposes are available at differentlevels of aggregation. Based on the available data, individual-level or aggregated-level models are used in SAE.However, parameter estimates obtained from individual and aggregated level analysis may be different, in practice.This may happen due to some substantial contextual or area-level effects in the covariates which may be misspecifiedin individual-level analysis. If small area models are going to be interpretable in practice, possible contextualeffects should be included. Ignoring these effects leads …

Embedding Distributed Learning Algorithms In Wireless Ad-Hoc Control Networks, A. Desmet, F. Naghdy, M. Ros

Dr Montserrat Ros

With the advances in soft computing techniques and agent technologies, the concept of home ambient intelligence is becoming more and more realistic. Living in a building that adapts itself to the users and assists them in reducing their energy consumption is now within reach. The main technical barrier comes from hardware: servers and industrial control networks do not fit in a house. With the availability of dedicated wireless solutions and low-cost small computation units, the platform to implement task distribution in a control network is now feasible and cost efficient. This paper explores the possibilities of fitting a distributed learning …

The Return Of Dr. Strangelove: How Austerity Makes Us Stop Worrying And Love The Bomb…And Cyber War, Jan Kallberg, Adam Lowther

Jan Kallberg

With sequestration looming—generating significant cuts to defense spending—the United States may find itself increasingly relying on nuclear and cyber deterrence as an affordable way to guarantee national sovereignty and prevent major conflict. While earlier defense planning and acquisitions were based on economic conditions that no longer exist, Congress’ options to balance the budget by cutting defense spending are politically palatable because far fewer American are “defense voters” than “social welfare voters,” according to a number of recent public opinion surveys.

Scaling Bayesian Network Parameter Learning With Expectation Maximization Using Mapreduce, Erik B. Reed, Ole J. Mengshoel

Ole J Mengshoel

Mapreduce For Bayesian Network Parameter Learning Using The Em Algorithm, Aniruddha Basak, Irina Brinster, Ole J. Mengshoel

Ole J Mengshoel

Atollgame: A Companion Modelling Experience In The Pacific, A Dray, Pascal Perez, Christophe Le Page, Patrick D'Aquino, Ian White

Professor Pascal Perez

Multi-Agent Systems (MAS) have been developed to study the interaction between societies and the environment. Here we use MAS in conjunction with a Companion Modelling (ComMod) approach to develop a Negotiation Support System for groundwater management in Tarawa, Republic of Kiribati. In agreement with the complex and dynamic nature of the processes under study, the ComMod approach requires a permanent and iterative confrontation between theories and field circumstances. Therefore, it is based on repetitive back and forth steps between the model and the field situation. The methodology applied in Tarawa relies on 3 successive stages. First, a Global Targeted Appraisal …

Complex Science For A Complex World: An Introduction, Pascal Perez, David Batten

Professor Pascal Perez

No abstract provided.

Safe Water For People In Low, Small Island Pacific Nations: The Rural-Urban Dilemma, Ian White, Tony Falkland, Taboia Metutera, Mourongo Katatia, Tererei Abete-Reema, Marc Overmars, Pascal Perez, Anne Dray

Professor Pascal Perez

The issue of ensuring that growing communities in small island countries have access to safe water and adequate sanitation is examined in Kiribati, whose islands are spread over three million square kilometres in the central Pacific. Its coral island communities have water supply and sanitation problems among the most difficult in the world. Formulaic developed-world approaches, models, techniques and toolboxes that do not consider the social and cultural context have had little success. Changes in approach at the international, national and local levels are called for, and the resourcing of village-level water and sanitation committees would return ownership and control …

A Spatial Agent-Based Model To Explore Scenarios Of Adaptation To Climate Change In An Alpine Tourism Destination, Stefano Balbi, Pascal Perez, Carlo Giupponi

Professor Pascal Perez

A vast body of literature suggests that the European Alpine region may be one of the most sensitive to climate change impacts. Adaptation to climate change of Alpine socioecosystems is increasingly becoming an issue of interest for the scientific community while the people of the Alps are often unaware of or simply ignore the problem. ClimAlpTour is a European research project of the Alpine Space Programme, bringing together institutions and scholars from all countries of the Alpine arch, in view of dealing with the expected decrease in snow and ice cover, which may lead to a rethinking of tourism development …

Simreef And Reefgame: Gaming For Integrated Reef Research And Management, Deborah Cleland, Anne Dray, Pascal Perez, Rollan Geronimo

Professor Pascal Perez

As threats to coastal and ocean systems grow in scale and complexity, the calls for new approaches to research and management grow in volume. The Modeling and Decision Support Working Group (MDSWG) of the CRTR Program has developed two participatory gaming tools that address the need for integrative approaches to coral reef management. SimReef is a regional model and role-play game aimed at policy makers and industry representatives. It simulates coastal development trajectories and trade-offs between environmental, social and economic concerns. ReefGame is a local-level model and board game that helps local people and reef managers explore interactions between livelihoods, …

The Atollgame Experience: From Knowledge Engineering To A Computer-Assisted Role Playing Game, A Dray, Pascal Perez, Natalie Jones, Christophe Le Page, Patrick D'Aquino, Ian White, Titeem Auatabu

Professor Pascal Perez

This paper presents the methodology developed to collect, understand and merge viewpoints coming from different stakeholders in order to build a shared and formal representation of the studied system dealing with groundwater management in the low-lying atoll of Tarawa (Republic of Kiribati). The methodology relies on three successive stages. First, a Global Targeted Appraisal focuses on social group leaders in order to collect different standpoints and their articulated mental models. These collective models are partly validated through Individual Activities Surveys focusing on behavioural patterns of individual islanders. Then, these models are merged into a single conceptual one using qualitative analysis …

Towards An Art And Science Of Decision Aiding For Water Management And Planning: A Participatory Modelling Process, Katherine A. Daniell, Ian White, Nils Ferrand, Alexis Tsoukias, Stewart Burn, Pascal Perez

Professor Pascal Perez

Planning and management of water resources are faced with increasingly high levels of complexity, uncertainty and conflict. Traditional technical and top-down management strategies have proved inadequate, forcing a move to more "integrated" forms of management, planning and decision making that can include stakeholders and communities, as well as technical experts and policy makers. These integrated forms of management require not only good technical or scientific ability, but a range of "art-like" skills including communication, creativity and the capacity to acknowledge and integrate diverse points of view. However, processes designed to aid such inter-organisational or multi-stakeholder decisionmaking are rare and in …

An Ontology-Based Simulation Model Exploring The Social Contexts Of Psychostimulant Use Among Young Australians, Pascal Perez, Anne Dray, Paul Dietze, David Moore, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan L. Hudson, Lisa Maher, Gabriele Bammer

Professor Pascal Perez

The principal anthropogenic factors driving reef degradation have been known for years, if not decades. Overfishing, sedimentation and nutrient loads are just some of the key impacts of human activities in and around reef communities. Therefore, the future of reefs does not rely on generating new knowledge, but rather on implementing and integrating the knowledge we already have. This will require creating effective links between researchers, managers and communities to promote mutual learning, negotiation and collaborative action for reef management. Combining agent-based models and role-play games, through a technique known as Companion Modelling (ComMod), creates a dynamic and interactive setting …

Waypoints On A Journey Of Discovery: Mental Models In Human Environment Interactions, Timothy Lynam, Raphael Mathevet, Michel Etienne, Samantha Stone-Jovicich, Anne Leitch, Nathalie Jones, Helen Ross, Derick Du Toit, Sharon Pollard, Harry Biggs, Pascal Perez

Professor Pascal Perez

Although the broad concept of mental models is gaining currency as a way to explore the link between how people think and interact with their world, this concept is limited by a theoretical and practical understanding of how it can be applied in the study of human-environment relationships. Tools and processes are needed to be able to elicit and analyze mental models. Because mental models are not directly observable, it is also important to understand how the application of any tools and processes affects what is measured. Equally important are the needs to be clear on the intent of the …

Embracing Social Uncertainties With Complex Systems Science, Pascal Perez

Professor Pascal Perez

Human ecosystems are real-life systems characterized by very strong and longterm interactions between human communities and their environment; as such they constitute an expansion of the ecological concept of ecosystem. According to Stepp and colleagues (2003), human ecosystems not only process matter and energy flows, but - and more specifically - information flows as well. Therefore, they display very specific characteristics due to our ability to communicate and learn from others, creating the conditions for co-evolutionary processes in which chance lends a hand to necessity. Bradbury (2006) argues that, until recently, human beings had been able to adapt to changes …

Evaluating Participatory Modeling: Developing A Framework For Cross-Case Analysis. Socio-Economics And The Environment In Discussion (Seed), Natalie A. Jones, Pascal Perez, Thomas G. Measham, Gail J. Kelly, Patrick D'Aquino, Katherine Daniell, Anne Dray, Nils Ferrand

Professor Pascal Perez

Participatory modeling is increasingly recognised as an effective way to assist collective decision-making processes in the domain of natural resource management. This paper introduces a framework for evaluating projects that have adopted a participatory modeling approach. This framework – known as the ‘Protocol of Canberra’ – was developed through a collaboration between French and Australian researchers engaged in participatory modeling and evaluation research. The framework seeks to assess the extent to which different participatory modeling practices reinforce or divert from the theoretical assumptions they are built upon. The paper discusses the application of the framework in three case-studies, two from …

Agents, Idols, And Icons, Pascal Perez

Professor Pascal Perez

Since the early 1960s, Artificial Intelligence has cherished the ambition to design an artificial cognitive machine able to reproduce intimate aspects of human behaviour. Distributed Artificial Intelligence and its most recent avatars—Multi- Agent Systems—have developed the concept towards social interactions and societal dynamics, attracting the attention of sociologists and ethnographers who found new ways to elaborate or validate their theories. But populations of cognitive agents aren’t the real thing, despite the efforts of their designers. Furthermore, one must cautiously examine the rationale behind these often incredibly complex arrangements of algorithms, in order to assess the usefulness of such exercises. As …

Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar

Srinivas Sridhar

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal surface plasmon modes. A quantitative model based on effective medium theory is in excellent agreement with experimental data, and points to specific composite configurations and wavelength regimes where such structures can have applications as negative refraction media for imaging.

Possible Room-Temperature Ferromagnetism In Hydrogenated Carbon Nanotubes, Adam L. Friedman, Hyunkyung Chun, Yung Joon Jung, Don Heiman, Evan R. Glaser, Latika Menon

Yung Joon Jung

We find that ferromagnetism can be induced in carbon nanotubes (CNTs) by introducing hydrogen. Multiwalled CNTs grown inside porous alumina templates contain a large density of defects resulting in significant hydrogen uptake when annealed at high temperatures. This hydrogen incorporation produces H-complex and adatom magnetism which generates a sizable ferromagnetic moment and a Curie temperature near TC=1000  K. We studied the conditions for the incorporation of hydrogen, the temperature-dependent magnetic behavior, and the dependence of the ferromagnetism on the size of the nanotubes.

Possible Room-Temperature Ferromagnetism In Hydrogenated Carbon Nanotubes, Adam L. Friedman, Hyunkyung Chun, Yung Joon Jung, Don Heiman, Evan R. Glaser, Latika Menon

Donald Heiman

We find that ferromagnetism can be induced in carbon nanotubes (CNTs) by introducing hydrogen. Multiwalled CNTs grown inside porous alumina templates contain a large density of defects resulting in significant hydrogen uptake when annealed at high temperatures. This hydrogen incorporation produces H-complex and adatom magnetism which generates a sizable ferromagnetic moment and a Curie temperature near TC=1000  K. We studied the conditions for the incorporation of hydrogen, the temperature-dependent magnetic behavior, and the dependence of the ferromagnetism on the size of the nanotubes.

Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar

Donald Heiman

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal surface plasmon modes. A quantitative model based on effective medium theory is in excellent agreement with experimental data, and points to specific composite configurations and wavelength regimes where such structures can have applications as negative refraction media for imaging.

Negative Index Metamaterials Based On Metal-Dielectric Nanocomposites For Imaging Applications, L. Menon, W. T. Lu, A. L. Friedman, S. P. Bennett, D. Heiman, S. Sridhar

Latika Menon

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal surface plasmon modes. A quantitative model based on effective medium theory is in excellent agreement with experimental data, and points to specific composite configurations and wavelength regimes where such structures can have applications as negative refraction media for imaging.