Critical slip and time dependence in sea ice friction

Recent research into sea ice friction has focussed on ways to provide a model which maintains much of the clarity and simplicity of Amonton's law, yet also accounts for memory effects. One promising avenue of research has been to adapt the rate- and state- dependent models which are prevalent in rock friction. In such models it is assumed that there is some fixed critical slip displacement, which is effectively a measure of the displacement over which memory effects might be considered important. Here we show experimentally that a fixed critical slip displacement is not a valid assumption in ice friction, whereas a constant critical slip time appears to hold across a range of parameters and scales. As a simple rule of thumb, memory effects persist to a significant level for 10 s. We then discuss the implications of this finding for modelling sea ice friction and for our understanding of friction in general.

Managing a duopolistic water market with confirmed proposals. An experiment

We report results from experimental water markets in which owners of two different sources of water supply water to households and farmers. The final water quality consumed by each type of consumer is determined through mixing of qualities from two different resources. We compare the standard duopolistic market structure with an alternative market clearing mechanism inspired by games with confirmed strategies (which have been shown to yield collusive outcomes). As in the static case, complex dynamic markets operating under a confirmed proposals protocol yield less efficient outcomes because coordination among independent suppliers has the usual effects of restricting output and increasing prices to the users. Our results suggest that, when market mechanisms are used to allocate water to its users, the rule of thumb used by competition authorities can also serve as a guide towards water market regulation.

Trans/national dis/connections: silenced networks and strained belongings with reference to Albinia Catherine MacKay and Una Marson

This paper seeks to examine the particular operations of gender and cultural politics that both shaped and restrained possible 'networked' interactions between Jamaican women and their British 'motherlands' during the first forty years of the twentieth century. Paying particular attention to the poetry of Albinia Catherine MacKay (a Scots Creole) and the political journalism of Una Marson (a black Jamaica), I shall seek to examine why both writers speak in and of voices out of place. MacKay's poems work against the critical pull of transnational modernism to reveal aesthetic and cultural isolation through a model of strained belonging in relation to both her Jamaica home and an ancestral Scotland. A small number of poems from her 1912 collection that are dedicated to the historical struggle between the English and Scots for the rule of Scotland and cultural self-determination, some of which are written in a Scottish idiom, may help us to read the complex cultural negotiations that silently inform the seemingly in commensurability of location and locution revealed in these works. In contrast, Marson's journalism, although less known even than her creative writings, is both politically and intellectually radical in its arguments concerning the mutual articulation of race and gender empowerment. However, Marson remains aware of her inability to articulate these convictions with force in a British context and thereby of the way in which speaking out of place also silences her.

Biorefinery strategies for upgrading Distillers’ Dried Grains with Solubles (DDGS)

Distillers’ Dried Grains with Solubles (DDGS) is the major by-product of bioethanol and distillery plants. Due to its high content of proteins, water-soluble vitamins and minerals, DDGS has been long marketed as animal feed for livestock. EU legislation on liquid biofuels could raise the demand on bioethanol production in Europe, with a resulting increase in DDGS availability. DDGS contains a spectrum of complex organic macromolecules, particularly polysaccharides, in addition to proteins and vitamins, and its use as a starting raw material within a biomass-based biorefining strategy could lead to the development of multi-stream processes for the production of commodities, platform molecules or speciality chemicals, with concomitant economic benefits and waste reduction for bioethanol plants. The present review aims to outline the compositional characteristics of DDGS and evaluate its potential utilisation as a starting material for the production of added-value products. Parameters of influence on the chemical and physical characteristics of DDGS are discussed. Moreover, various pre-treatment strategies are outlined in terms of efficient DDGS fractionation into several added value streams. Additional processing steps for the production of medium and high added value compounds from DDGS are evaluated and their potential applications in the food and chemical industry sector are identified.

Glastonbury Abbey: archaeological investigations 1904-79

This volume reports on the results of the Glastonbury Abbey Archaeological Archive Project, a collaboration between the University of Reading and the Trustees of Glastonbury Abbey, funded principally by the Arts and Humanities Research Council. The project has reassessed and reinterpreted all known archaeological records from the 1908–79 excavations and made the complete dataset available to the public through a digital archive hosted by the Archaeology Data Service (http://dx.doi.org/10.5284/1022585). The scope of the project has included the full analysis of the archaeological collections of Glastonbury Abbey by thirty-one leading specialists, including chemical and compositional analysis of glass and metal and petrological analysis of pottery and tile, and a comprehensive geophysical survey conducted by GSB Prospection Ltd. For the first time, it has been possible to achieve a framework of independent dating based on reassessment of the finds and radiocarbon dating of surviving organic material from the 1950s excavations. The principal aim of the Glastonbury Abbey Archaeological Project was to set aside previous assumptions based on the historical and legendary traditions and to provide a rigorous reassessment of the archive of antiquarian excavations. This research has revealed that some of the best known archaeological ‘facts’ about Glastonbury are themselves myths perpetuated by the abbey’s excavators.

A photographic journey through Vietnam

This degree project consists of “A photographic journey through Vietnam”. One month was spent in Vietnam where the different aspects of the Vietnamese life were documented in images. The journey began in Hanoi and descended down the country to Ho Chi Minh City.The report describes the compositional elements of photography and makes an attempt to describe what a “good” image is. Furthermore it explains what equipment that is necessary for such a journey and how you can interact with the local population.When the journey came to an end, a photographic book consisting of 200 images was created. The report details the used workflow step by step. Finally the author has commented 20 of the selected images regarding their photographic composition.

Combates entre la memoria y la historia de Chile : Conflictos sobre el pasado reciente

The reestablishment of democracy in Chile has seen an intense debate about the events of the recent past, especially on the issue of human rights. From the very beginning, the Concertacion Government has been determined to discover the truth of the repression carried out by the national security forces with a series of commissions that have gathered the testimonies of victims and their relatives. These efforts have been resisted by conservative sectors linked to the dictatorship and the Armed Forces. There has been intense conflict in the media during the past 20 years about events that occurred during the rule of Salvador Allende and the Military Regime. In this regard, a great diversity of information has been produced which, together with the debate evoked, has enabled historians not only to rigorously and thoroughly reconstruct the operation of the state terror but also to explain how a significant sector of Chile’s civil society allowed that situation. This article presents, on one hand, different methodological tools in order to study the recent past and, on the other hand, the social discussion on how to do it.

Al-Mahdi - Gestalt och budskap : En litteraturstudie jämförande sudanesisk Mahdi och indisk Mahdi inom islam

Followers of three world religions, Judaism, Christianity and Islam are waiting for the Messiah. Muslims are even waiting for aspiritual leader al-Mahdi. Two different persons claimed the title of al-Mahdi, at the end of the nineteenth century. Theyappeared almost at the same time, at the totally different places of the earth, with a completely different message and underthe rule of the British colonial power. The aim of the study is to compare the both religious figures, Mirza Ghulam Ahmadfrom India and Muhammad Ahmad from Sudan regarding their different messages, to illustrate the social, political andreligious factors that lead to the entirely different profile and image of these two men and how their organizations havedeveloped after their death up till today. The result shows that the Sudanese Mahdi Muhammad Ahmad claimed hisMahdiship in the year 1881. He became a political leader in a time when Sudan was under the rule of a colonial power. Hetook advantage of the religion for personal purposes and tried to liberate his native country Sudan. The contemporaryMuslim clergy criticized him for his claim because the content of the Hadith traditions did not support his claim ofMahdiship. He maintained his sole right for the interpretation of religion and of the laws of Sharia. He made changes even inthe chief pillars of Islam by asserting that Jehad with sword was more imperative than the pilgrimage journey to Mecca. Heasserted that the Prophet Muhammad himself had entrusted him to launch the holy war against the non-believers. He hadimmense ambitions which were never fulfilled since he suddenly died four years after his claim for Mahdiship, in June 1885.This day his followers are organized as a political party in Sudan with a modest roll in the Sudanese politics. The IndianMahdi Mirza Ghulam Ahmad claimed in 1889 to be Mahdi, Mujaddid, Muhaddas, Messiah and a Prophet at a time of socialand political peace, though Islam as a religion was firmly pushed by the Hindu and Christian missionaries. He had no politicalambitions at all and was utterly loyal to the British colonial power. His mission was to crush the Cross and to demonstrateIslam’s excellence over all the religions of the world through overwhelming arguments. He proclaimed that Jesus was humanand a Prophet and not the son of God. Jesus survived from the cross and died a natural death after he had lived for manyyears. Ahmad claimed that God had commanded him to put stop to the religious wars. The contemporary Muslim clergyblamed him for being an imposter, melancholic and hypochondriac who had self invented the divine revelations. He died year1908, nineteen years after his claim and the communion he found is established today in more than hundred countries of theworld. Reasons for the breakdown of mission of the Sudanese Mahdi were that his objectives were political and he challengedthe colonial power with the sword. Another decisive factor was his sudden death merely four years after the beginning of hismission. Reasons for the success of Indian Mahdi were that his objectives were purely religious and he was wholly loyal to theforeign government. He survived nineteen years after the beginning of his mission which made it possible for him to create acommunion based on solid grounds. His followers continued on the same path and never engaged in local politics where everthey lived. For further studies it will be of great interest to study the life of Mirza Ghulam Ahmad and objectively examine thearguments he presented in support of his divine appointment. Furthermore it is enriching to study the organization andactivities of the Ahmadiyya Muslim community to explore if they are in accordance with the basic principles of Ahmad.

Describing Web Service Architectures through Design-by-Contract

Architectural description languages (ADLs) are used to specify a high-level, compositional view of a software application, specifying how a system is to be composed from coarse-grain components. ADLs usually come equipped with a formal dynamic semantics, facilitating specification and analysis of distributed and event-based systems. In this paper, we describe the TrustME, an ADL framework that provides both a process and a structural view of web service-based systems. We use Petri-net descriptions to give a dynamic view of business workflow for web service collaboration. We adapt the approach of Schmidt to define a form of Meyer's design-by-contract for configuring workflow architectures. This serves as a configuration-level means of constructing safer, more robust systems.

An Architectural Description Language for Enterprise Computing

Architectural description languages (ADLs) are used to specify high-level, compositional view of a software application. ADLs usually come equipped with a rigourous state-transition style semantics, facilitating specification and analysis of distributed and event-based systems. However, enterprise system architectures built upon newer middleware (implementations of Java’s EJB specification, or Microsoft’s COM+/ .NET) require additional expressive power from an ADL. The TrustME ADL is designed to meet this need. In this paper, we describe several aspects of TrustME that facilitate specification and anlysis of middleware-based architectures for the enterprise.

Trust-By-Contract: Modelling, Analysing and Predicting Behaviour in Software Architectures

Architecture description languages (ADLs) are used to specify high-level, compositional views of a software application. ADL research focuses on software composed of prefabricated parts, so-called software components. ADLs usually come equipped with rigorous state-transition style semantics, facilitating verification and analysis of specifications. Consequently, ADLs are well suited to configuring distributed and event-based systems. However, additional expressive power is required for the description of enterprise software architectures – in particular, those built upon newer middleware, such as implementations of Java’s EJB specification, or Microsoft’s COM+/.NET. The enterprise requires distributed software solutions that are scalable, business-oriented and mission-critical. We can make progress toward attaining these qualities at various stages of the software development process. In particular, progress at the architectural level can be leveraged through use of an ADL that incorporates trust and dependability analysis. Also, current industry approaches to enterprise development do not address several important architectural design issues. The TrustME ADL is designed to meet these requirements, through combining approaches to software architecture specification with rigorous design-by-contract ideas. In this paper, we focus on several aspects of TrustME that facilitate specification and analysis of middleware-based architectures for trusted enterprise computing systems.

Stratified resolution

We introduce a calculus of stratified resolution, in which special attention is paid to clauses that "define" relations. If such clauses are discovered in the initial set of clauses, they are treated using the rule of definition unfolding, i.e. the rule that replaces defined relations by their definitions. Stratified resolution comes with a powerful notion of redundancy: a clause to which definition unfolding has been applied can be removed from the search space. To prove the completeness of stratified resolution with redundancies, we use a novel combination of Bachmair and Ganzingerâ??s model construction technique and a hierarchical construction of orderings and least fixpoints.

Testing unit root based on partially adaptive estimation

This paper proposes unit tests based on partially adaptive estimation. The proposed tests provide an intermediate class of inference procedures that are more efficient than the traditional OLS-based methods and simpler than unit root tests based on fully adptive estimation using nonparametric methods. The limiting distribution of the proposed test is a combination of standard normal and the traditional Dickey-Fuller (DF) distribution, including the traditional ADF test as a special case when using Gaussian density. Taking into a account the well documented characteristic of heavy-tail behavior in economic and financial data, we consider unit root tests coupled with a class of partially adaptive M-estimators based on the student-t distributions, wich includes te normal distribution as a limiting case. Monte Carlo Experiments indicate that, in the presence of heavy tail distributions or innovations that are contaminated by outliers, the proposed test is more powerful than the traditional ADF test. We apply the proposed test to several macroeconomic time series that have heavy-tailed distributions. The unit root hypothesis is rejected in U.S. real GNP, supporting the literature of transitory shocks in output. However, evidence against unit roots is not found in real exchange rate and nominal interest rate even haevy-tail is taken into a account.

O estado necessário para a democracia possível na América latina

Uma democracia consolidada pressupõe um estado capaz, e para ambos é necessária uma nação forte e uma sociedade civil ativa. Diversas democracias na América Latina não alcançaram tais requisitos porque não completaram suas respectivas revoluções capitalistas, e o excedente econômico continua dependendo do controle direto do estado. Este fato demonstra que a qualidade das democracias varia de país para país, e prevê que as democracias possíveis nos países mais pobres serão necessariamente democracias limitadas. Desde que a democracia tornou-se uma justificativa para pressões e intervenções externas, é um erro incluir no conceito de democracia mais do que as necessidades mínimas, práticas. Por outro lado, para melhorar a democracia é necessário aumentar a capacidade do estado não apenas para assegurar o respeito às leis, mas também para promover o desenvolvimento econômico e social.

Democracia e revolução capitalista

A democracia tornou-se o regime preferido apenas no século XX. Para entender esse processo, um método puramente de escolha racional não é suficiente. O autor busca um novo fato histórico que levou a essa mudança de preferência e o encontra na Revolução Capitalista. Por parte dos capitalistas, a democracia é p regime político que melhor assegura os direitos de propriedade e o cumprimento de contratos. Por parte dos trabalhadores, é o regime que garante que os salários cresçam mais proporcionalmente em relação aos lucros. No plano internacional, atualmente, os principais países não têm inimigos dentre ou outros estados-nação. Aos poucos, a Política de globalização substitui o antigo sistema a Diplomacia de Equilíbrio de Poderes a medida em que a globalização é regulamentada, e o império da lei emerge no plano internacional. Globalização é inerentemente injusta para com os países pobres e em desenvolvimento, que são incapazes de competir em um mundo onde a competição prevalece em toda a parte. Tais países são simplesmente excluídos do sistema ou, frustrados, recorrem ao terrorismo. Através do debate e argumentação, será possível criar um sistema internacional legal menos injusto. E através dele, há esperança de que a idéia de um governo internacional deixe de ser mera utopia.