Littérature scientifique sur le sujet « Majorca (Spain) – Boundaries »

The ground state behavior of the biaxial spin-1/2 chain with free open edges is studied. Using the exact Bethe ansatz solution we show that there can exist boundary bound states for many finite values of the exchange coupling constants. The non-trivial interaction between spins produces charging of the vacua of the model and boundary bound states. Our theory also describes the behavior of the spinless fermion chain with pairing (the Kitaev chain) and an interaction between fermions at neighboring sites for free open boundaries. Therefore, the simple case of noninteracting fermions simplest boundary states are Majorana edge modes.

Defence date: 21 January 2000
Examining board: Jean-Pierre Amalric (supervisor) ; Gérard Delille ; Roebrt Rowland ; Bernard Vincent
PDF of thesis uploaded from the Library digitised archive of EUI PhD theses completed between 2013 and 2017

The last twenty years have been a time of intense public debates on social policy in India. There have also been major initiatives, such as the National Rural Employment Guarantee Act, as well as resilient inertia in some fields. This book brings together some of Jean Drèze's contributions to these debates, along with other short essays on social development. The essays span the gamut of critical social policies, from education and health to poverty, nutrition, child care, corruption, employment, and social security. There are also less predictable topics such as the caste system, corporate power, nuclear disarmament, the Gujarat model, the Kashmir conflict, and universal basic income. The book aims at enlarging the boundaries of social development, towards a broad concern with the sort of society we want to create. The concluding essay, on public-spiritedness and solidarity, argues that the cultivation of enlightened social norms is an integral part of development. "Jholawala" has become a disparaging term for activists in the Indian business media. This book affirms the learning value of collective action combined with sound economic analysis. In his detailed introduction, the author argues for an approach to development economics where research and action are complementary and interconnected.

The purpose of this chapter is to provide a conceptual/theoretical analysis of intranets and knowledge management in virtual organizations for both academics and practitioners. Virtual organizations are a major part of the new business models that have recently emerged. Intranets are introduced as a tool for managing knowledge in virtual, as well as traditional, organizations. The chapter begins with an overview of knowledge management and how it relates to virtual organizations, including a discussion of the forces creating the need for knowledge management and some of the components of knowledge management. The chapter then introduces intranets as a tool and methodology for managing knowledge, especially in virtual organizations. It discusses a number of key issues related to intranets and knowledge management, including the intranet’s ability to span geographic and temporal boundaries, to share information, to facilitate communication and to become a collaborative work space. Other issues discussed include methods for dealing with information overload, the ability of intranets to help provide identity and cohesion for virtual teams, and so forth. The chapter gives clear examples of how intranets are a vital knowledge management tool in virtual organizations, as well as in other new business models. Finally, the chapter ends with a discussion of future trends in intranets in connection with knowledge management in virtual organizations.

In the nineteenth century and the first half of the twentieth century, political and economic power was concentrated in just a few countries. Having eclipsed the most mighty early modern empires—those of Spain and Portugal, the Ottoman Empire, The Netherlands, and the Scandinavian countries— Britain, France, the Russian, and the Austro-Hungarian Empires became the major European powers. Later, these were joined by the newly formed countries of Germany and Italy, together with the United States of America and Japan. In these countries elites drew their might not only from the industrial revolution but also from the economic exploitation of their ever-increasing colonies. Colonialism, a policy by which a state claims sovereignty over territory and people outside its own boundaries, often to facilitate economic domination over their resources, labour, and markets, was not new. In fact, colonialism was an old phenomenon, in existence for several millennia (Gosden 2004). However, in the nineteenth century capitalism changed the character of colonialism in its search for new markets and cheap labour, and the imperial expansion of the European powers prompted the control and subjugation of increasingly large areas of the world. From 1815 to 1914 the overseas territories held by the European powers expanded from 35 per cent to about 85 per cent of the earth’s surface (Said 1978: 41; 1993: 6). To this enlarged region areas of informal imperialism (see Part II of this book) could be added. However, colonialism and informal colonialism were not only about economic exploitation. The appropriation of the ‘Other’ in the colonies went much further, and included the imposition of an ideological and cultural hegemony throughout each of the empires. The zenith of this process of colonization was reached between the 1860s and the First World War, in the context of an increasingly exultant nationalism. In a process referred to as ‘New Imperialism’, European colonies were established in all the other four continents, mainly in areas not inhabited by populations with political forms cognate to the Western powers. In the case of Africa, its partition would be formally decided at an international meeting—the Berlin Conference of 1884–5.

The university is one of Europe’s great gifts to the world. There had been sophisticated centres of learning in Classical Athens and Alexandria, in China, and then in North Africa and Spain during the Islamic world’s scientific flowering. But it is Europe’s universities which gave birth to the humanism of the Renaissance, drove the Reformation, led the rise of empirical science, and promoted the emergence of critical history. They are still extending the boundaries of knowledge today, as part of a global enterprise which is heavily influenced by the European model. They emerged in the twelfth century. The first wave of a dozen or so, including Bologna, Paris, and Oxford, already comprised different types of university, reflecting their different origins depending on which came first, the chicken or the egg, the teacher or the student. In Bologna, reputed to have been founded in 1088 and hence Europe’s oldest university, the student is thought to have come first. Groups of students were looking for training to get qualifications that would help them practise medicine or law and employed teachers to help them. There ‘the lecturing staff had to submit to a competitive trial to win the custom of their fee paying consumers . . . teaching was viewed as a commodity like any other and it was logical that new students should sample lecture courses before making their academic purchase’. They were mature students who had probably already started work and knew what extra training they needed to advance in their profession. By contrast in Northern Europe the university began with teachers setting up universities: they had much younger students who were more dependent on them. (They were called masters, reflecting the origins of the model in apprenticeships.) These universities tended to be less vocational as the routes into professions such as the law or medicine were instead via apprenticeships. Towns gave these new institutions a mixed welcome—and sometimes still do. Tensions between town and gown boiled over into violence. Universities looked to the Church, the major countervailing power of the time, for protection from hostile locals.

The architecture, conventionally implemented in marine installations, for the distribution of electrical power is the Radial scheme. In a Radial scheme, power is routed to each consumer directly from a centrally positioned source, such as a switchboard or an MCC. Since the consumers are dispersed in a large, highly complex, three dimensional environment, implementation of a Radial scheme results in many cables spanning over large distances of the ship. An alternative strategy is to introduce power into major portions of the vessel via a power bus and hang consumers locally from the bus. Such major portions of the vessel where the power bus brings power in, are termed “Zones”. The boundaries of the electrical Zones are defined such that they coincide with the fire-tight and watertight zonings, and also with the demarcation lines of construction modules. In the Zonal scheme, only the power bus needs to span the ship, while consumers in each Zone are fed radially in a localized environment and hence require only short cable runs, which also lend themselves well for pre-fit into each construction module.

Major factors affecting the reliability of railroad or transit systems are assigned at the design stage of a project. After the design of the system has been finalized changes that can be implemented to improve the reliability are generally of the second order level and subsequently have a lesser effect. An area that has traditionally been a source of unreliable operation for railroad and transit systems has been the interfaces between the various systems. The system-to-system interfaces cover the whole of the range of areas in a railroad or transit system and are often visible to the passengers using the railroad or transit system. The interfaces to be controlled have a wide variety of characteristics and features. These interfaces can consist of mechanical issues like for the platform and vehicle interface. The interfaces can also be mainly electrical in nature as with the control of conducted interference currents at the vehicle power supply interface to achieve compatibility. Interfaces may also be a mixture of mechanical and electrical characteristics. Railroad and transit systems are becoming more sophisticated, it is now common for a rail vehicle to have multiple microprocessors on board to control the various systems needed for a modern rail vehicle. Similar technologies are also being applied to different systems of a railroad or transit system. For example the technology required to control a vehicle propulsion system is very similar to that required by the modern regenerative substation. Modern integrated systems are also spreading across the traditional system boundaries. For example an integrated passenger information system for an LRT or Metro system would span vehicles, stations, train control and communication systems. A key factor to improving the reliability of a railroad or transit system is early and effective control of the system interfaces and having the appropriate organization(s) responsible for the interface. This paper will explore the factors that would need to be considered for appropriate management of the interfaces. It will relate the management of the interfaces to the types of contract mechanisms that can be used for procurement of equipment and consider the associated advantages and risks.

Harlequin ducks (Histrionicus histrionicus) are sea ducks that migrate inland each spring to nest along fast-flowing mountain streams. They are considered one of the most imperiled duck species in North America and occur in two distinct populations on the Atlantic and Pacific coasts. The Pacific coast population includes Washington State, where harlequin ducks breed in the Olympic, Cascade, and Selkirk Mountains. This species is designated as a Management Priority Species by the National Park Service within North Cascades National Park Service Complex (NOCA). This report summarizes harlequin duck surveys conducted during 15 years across a 27-year period (1990 and 2017) on major streams within NOCA, and incidental observations collected from 1968–2021. The primary objectives of these surveys were to 1) document the distribution and abundance of harlequin duck observations within NOCA boundaries, 2) describe productivity (number of broods and brood size), 3) describe breeding chronology of harlequin ducks, and 4) describe habitat characteristics of breeding streams. Sixty-eight stream surveys over 15 years resulted in observations of 623 individual harlequin ducks comprising various demographics, including single adults, pairs, and broods. In addition, we collected 184 incidental observations of harlequin ducks from visitors and staff between 1968–2021. Harlequin ducks were observed on 22 separate second- to sixth-order streams throughout NOCA across the entire 53-year span of data, both incidentally and during harlequin duck surveys by Park staff. Harlequin ducks were detected on 8 of the 13 streams that were actively surveyed. Excluding recounts, 88.7% (n = 330) of individual harlequin duck observations during surveys occurred in the Stehekin River drainage. Between all surveys and incidental observations, 135 unpaired females without broods were sighted across all NOCA waterways. Thirty-nine broods were recorded between NOCA surveys and incidental observations, with a mean brood size of 3.61 (± 1.44 SD; range = 2–10). Breeding pairs were recorded as early as April 5 and were seen on streams until June 15, a period of less than seven weeks (median: May 2), but most pairs were observed within a 3-week span, between April 26 and May 17. Single females (unpaired with a male, with (an)other female(s), or with a brood) were observed on streams between April 26 and August 25 (median: July 3), though most observations were made within a 5-week period between June 12 and July 19. Habitat data collected at adult harlequin duck observation sites indicate that the birds often used stream reaches with features that are characteristic of high-energy running water. While adults occupied all instream habitat types identified, non-braided rapids and riffles were used most frequently, followed by pools and backwaters. Larger instream substrate sizes (cobbles and boulders) were present at most observation sites. Adult harlequin ducks were more often found at locations that lacked visible drifting or lodged woody debris, but drift debris was a slightly more abundant debris type. The presence of gravel bars and at least one loafing site was common. Adult harlequin ducks were more often observed in association with vegetation that offered some cover over the channel, but not where banks were undercut. The average channel width at adult observation sites was 34.0 m (range: 6-80 m; n = 114) and 27.6 m (± 15.7 m; range: 10-60 m; n = 12) at brood observation sites. Compared to adult harlequin duck sites, broods were observed more frequently in low velocity habitat (pools, backwaters), but rarely in rapids. Cobble and boulder substrates were still the most dominant substrate type. Contrary to adult ducks, broods were observed most often observed in meandering stream channels, a morphology indicative of low gradient, low velocity stream reaches. Most broods were observed in stream reaches with gravel bars, loafing sites, and...