Tolling, Capacity Selection and Equilibrium Problems with Equilibrium Constraints

An Equilibrium problem with an equilibrium constraint is a mathematical construct that can be applied to private competition in highway networks. In this paper we consider the problem of finding a Nash Equilibrium regarding competition in toll pricing on a network utilising 2 alternative algorithms. In the first algorithm, we utilise a Gauss Siedel fixed point approach based on the cutting constraint algorithm for toll pricing. In the second algorithm, we extend an existing sequential linear complementarity approach for finding Nash equilibrium subject to Wardrop Equilibrium constraints. Finally we consider how the equilibrium may change between the Nash competitive equilibrium and a collusive equilibrium where the two players co-operate to form the equivalent of a monopoly operation

OATS - Open Source Assistive Technology - a way forward

The global Assistive Technology(AT)and Alternative and Augmentative Communication (AAC) software field, while expanding all the time, remains small land very specialised. AT is a relatively under funded field with its players widely spread across the globe. Open sourcing, if managed sensibly and creatively could offer the AT field an inexpensive opportunity to create, share, and above all disseminate good products that have high AT end user value but no (or relatively little)commercial interest or return. Open sourcing offers great potential for AT software users, however currently there are a number of barriers that stop its use in AT situations. It is generally difficult to find on the Internet and there are no specific areas dedicated to developing or downloading AT software. Open source software can also be unfriendly to install, often obliging the user to download many different packages before it can be used. This project is investigating the viability of the open source model for the future development of AT software. The OATS project removes these barriers to Open Source AT software: users will have a single point of contact for obtaining open source software and developers will have a forum to write software to meet the needs of specific users. The potential uses and market factors involved with Open Source AT software will be investigated and the underlying concepts promoted. Open Sourcing is a well-established and growing method of software development and it has potential to be beneficial within the Assistive Technology field. Open Source development allows multiple developers to work on software simultaneously even on different sides of the world it also encourages a very close relationship between the user and the developer. Many developers are looking to use their skills on interesting, challenging and worthwhile projects and offer a potential resource for the field that has not so far been utilised. Open Source also allows customisation to software œ an important aspect when working with such a diverse range of users as exist within the Assistive Technology community. Further to this, Open Source promotes common standards œ something very much lacking in existing Assistive Technology software œ and could allow better portability for users between programs. The main deliverable of this project is a website where users can find appropriate software to meet their needs and Open Source developers can find exciting and interesting projects. This software 'Repository' has a user-friendly web interface to allow users to browse the software and download/installitwith ease. The second part of the website, the 'Forge', allows software developers to find motivating, interesting and useful projects. The 'Forge' also provides a wide range of Open Source development tools including Subversion CVS (a tool to enable 'source code' to be stored on-line and for multiple developers to access it)and Trac(a project management tool and bug-tracking system). The site is developed using Plone - a powerful content management system that allows users control over their own project areas and provides a range of tools such as polls, noticeboards, FAQs etc. The website is fully accessible and meets the W3C WAI guidelines. To summarise the OATS project and website offers: - Downloadable Open Source AT software that is of sufficient quality to disseminate widely. - A 'forge' for the development of new Open Source AT software based on specific user needs. - A searchable list of links to other related websites - A discussion forum to promote discussion between end users, AT professionals and Open Source developers. And, in the longer term, itcouldalso provide: - Specific solutions to individual needs by 'tuning' existing applications - End users with help to develop solutions themselve

Contentment or containment? Consumption and the lesbian and gay community in Singapore

This article explores how gay men and lesbians in Singapore appear content to prioritise availability of consumer goods and services, lifestyle comfort and the availability of artistic representations over civil and political rights and social/political change. Contentment here acts as a powerful strategy of political and social containment of gays and lesbians who continue exist under the shadow of governmental erasure, censorship and oppression

OATS - Open Source Assistive Technology - a way forward

The global Assistive Technology(AT)and Alternative and Augmentative Communication (AAC) software field, while expanding all the time, remains small land very specialised. AT is a relatively under funded field with its players widely spread across the globe. Open sourcing, if managed sensibly and creatively could offer the AT field an inexpensive opportunity to create, share, and above all disseminate good products that have high AT end user value but no (or relatively little)commercial interest or return. Open sourcing offers great potential for AT software users, however currently there are a number of barriers that stop its use in AT situations. It is generally difficult to find on the Internet and there are no specific areas dedicated to developing or downloading AT software. Open source software can also be unfriendly to install, often obliging the user to download many different packages before it can be used. This project is investigating the viability of the open source model for the future development of AT software. The OATS project removes these barriers to Open Source AT software: users will have a single point of contact for obtaining open source software and developers will have a forum to write software to meet the needs of specific users. The potential uses and market factors involved with Open Source AT software will be investigated and the underlying concepts promoted. Open Sourcing is a well-established and growing method of software development and it has potential to be beneficial within the Assistive Technology field. Open Source development allows multiple developers to work on software simultaneously even on different sides of the world it also encourages a very close relationship between the user and the developer. Many developers are looking to use their skills on interesting, challenging and worthwhile projects and offer a potential resource for the field that has not so far been utilised. Open Source also allows customisation to software œ an important aspect when working with such a diverse range of users as exist within the Assistive Technology community. Further to this, Open Source promotes common standards œ something very much lacking in existing Assistive Technology software œ and could allow better portability for users between programs. The main deliverable of this project is a website where users can find appropriate software to meet their needs and Open Source developers can find exciting and interesting projects. This software 'Repository' has a user-friendly web interface to allow users to browse the software and download/installitwith ease. The second part of the website, the 'Forge', allows software developers to find motivating, interesting and useful projects. The 'Forge' also provides a wide range of Open Source development tools including Subversion CVS (a tool to enable 'source code' to be stored on-line and for multiple developers to access it)and Trac(a project management tool and bug-tracking system). The site is developed using Plone - a powerful content management system that allows users control over their own project areas and provides a range of tools such as polls, noticeboards, FAQs etc. The website is fully accessible and meets the W3C WAI guidelines. To summarise the OATS project and website offers: - Downloadable Open Source AT software that is of sufficient quality to disseminate widely. - A 'forge' for the development of new Open Source AT software based on specific user needs. - A searchable list of links to other related websites - A discussion forum to promote discussion between end users, AT professionals and Open Source developers. And, in the longer term, itcouldalso provide: - Specific solutions to individual needs by 'tuning' existing applications - End users with help to develop solutions themselve

Reflections on developing a tool for creating visual representations of learning designs: towards a visual language for learning designs

Over the past four years we have been developing CompendiumLD, a software tool for designing learning activities using a flexible visual interface. It has been developed as a tool to support lecturers, teachers and others involved in education to help them articulate their ideas and map out a design or learning sequence. CompendiumLD is a specialised version of Compendium, a tool for managing connections between information and ideas, which has been applied in many domains including the mapping of discussions and arguments. As most of the core knowledge mapping facilities provided by Compendium are included within CompendiumLD, it can be used for learning design, and applied it to other information mapping and modelling problems. Evidence gathered since CompendiumLD’s first release has shown the many conditions in which it is likely to be applied and appreciated by users, and that the need for visualising learning designs as a solution to understanding how all components of planned learning and teaching fit together may continue to grow. Furthermore, the use of technology is making the process of creating courses more complex. We explore these challenges and conclude with some reflections on the developments in visual representation needed to further facilitate the modelling of today and tomorrow’s complex learning situations

Representing the Process of Machine Tool Calibration in First-order Logic

Machine tool calibration requires a wide range of measurement techniques that can be carried out in many different sequences. Planning a machine tool calibration is typically performed by a subject expert with a great understanding of International standards and industrial best-practice guides. However, it is often the case that the planned sequence of measurements is not the optimal. Therefore, in an attempt to improve the process, intelligent computing methods can be designed for plan suggestion. As a starting point, this paper presents a way of converting expert knowledge into first-order logic that can be expressed in the PROLOG language. It then shows how queries can be executed against the logic to construct a knowledge-base of all the different measurements that can be performed during machine tool calibration

The Iron K Line Profile of IRAS 18325-5926

IRAS 18325-5926 is an X-ray bright, Compton-thin, type-2 Seyfert galaxy and it was the first Seyfert 2 in which the presence of a broad Fe K-alpha emission line was claimed. However, although the structure of the Fe line appears broad, there is tentative evidence that it may comprise multiple lines. Nevertheless, previous analyses have only consisted of fitting standalone broad components to the Fe K band. Here, we have analyzed all available X-ray CCD data from Suzaku, XMM-Newton and ASCA to fully investigate the nature of the emission complex by testing broad-band physical models and alternative hypotheses. We find that both a model consisting of broad, blurred reflection from an ionized accretion disc and a model consisting of cold, neutral reflection plus narrow emission lines from highly-ionized photoionized gas (log \xi = 3.5) offer statistically comparable fits to the data although the true reality of the Fe line cannot currently be determined with existing data. However, it is hoped that better quality data and improved photon statistics in the Fe K band will allow a more robust distinction between models to be made.Comment: Accepted by MNRAS; 13 pages; 10 figures; 2 table

Effective three-body interactions via photon-assisted tunneling in an optical lattice

We present a simple, experimentally realizable method to make coherent three-body interactions dominate the physics of an ultracold lattice gas. Our scheme employs either lattice modulation or laser-induced tunneling to reduce or turn off two-body interactions in a rotating frame, promoting three-body interactions arising from multi-orbital physics to leading-order processes. This approach provides a route to strongly-correlated phases of lattice gases that are beyond the reach of previously proposed dissipative three-body interactions. In particular, we study the mean-field phase diagram for spinless bosons with three- and two- body interactions, and provide a roadmap to dimer states of varying character in 1D. This new toolset should be immediately applicable in state-of-the-art cold atom experiments.Comment: 11 pages, 6 figure