Solitons are non-dissipative, nontrivial solutions of partial differential equations. In many cases their stability is well understood, e.g. there can be topological reasons that prevent a... Show moreSolitons are non-dissipative, nontrivial solutions of partial differential equations. In many cases their stability is well understood, e.g. there can be topological reasons that prevent a localised lump of energy to dissolve and become dissipative. However, there are very persistent, soliton-like objects even when there is no obvious conservation law that would guarantee stability and explain longevity. This thesis considers such solutions, called oscillons, that appear in variety of nonlinear scalar theories. In essence, they are persistent oscillations of the field around the (local) minimum of the potential. A numerical study of oscillons in two spatial dimensions is presented. Use of absorbing boundary conditions in the numerical grid enables the study of radiation losses over a long period of time and permits quantitative approach to the lifetime of oscillons. Furthermore, it is shown that oscillons are emitted by collapsing domains, which way they could come into being in nature, e.g. in the conditions met in the very early Universe. Show less
This volume is an archaeobotanical study of agricultural practices in the Moselle valley and the Meuse-Demer-Scheldt regions during the Bronze Age and Early Iron Age. It is split into three parts:... Show moreThis volume is an archaeobotanical study of agricultural practices in the Moselle valley and the Meuse-Demer-Scheldt regions during the Bronze Age and Early Iron Age. It is split into three parts: The Framework, The Botanical Research, and The Analysis, with the core of the book being focused on 24 sites, mainly in and around Lorraine. Show less
Bibliometric maps of science are landscapes of scientific research fields created by quantitative analysis of bibliographic data. In such maps the 'cities' are, for instance, research topics.... Show moreBibliometric maps of science are landscapes of scientific research fields created by quantitative analysis of bibliographic data. In such maps the 'cities' are, for instance, research topics. Topics with a strong cognitive relation are in each other's vicinity and topics with a weak relation are distant from each other. These maps have several domains of application. As a policy supportive tool they can be applied to overview the structure of a research field and to monitor its evolution. This book contributes to the development of this application of bibliometric maps. Show less
Rockets or launch vehicles, though sharing the same technology, have both military and civil applications: they can be used as missiles or as 'ordinary' transportation vehicles. As a consequence,... Show moreRockets or launch vehicles, though sharing the same technology, have both military and civil applications: they can be used as missiles or as 'ordinary' transportation vehicles. As a consequence, national security and foreign policy considerations stand in the way of the international launch industry becoming a normal service industry subject to free trade (GATS) principles. This dissertation discusses this conflict between national security and trade interests and the way it affects the United States launch trade relations with China, Russia and Europe. It also analyzes the extent to which the respective U.S. laws, policies and practices, in particular those relating to the export of satellites and launchers, restrict the development of these and other countries' commercial launch activities, and it reviews the prospects for a - GATS or space law-based - liberalization of the international trade in launch services. Show less
De wetgever gaat er steeds meer toe over in regelgeving te verwijzen naar (technische) normalisatienormen die via zelfregulering zijn opgesteld. Deze zogeheten NEN-normen worden in Nederland... Show moreDe wetgever gaat er steeds meer toe over in regelgeving te verwijzen naar (technische) normalisatienormen die via zelfregulering zijn opgesteld. Deze zogeheten NEN-normen worden in Nederland vastgesteld en gepubliceerd door de Stichting Nederlandse Normalisatie-Instituut (NNI). Door de verwijzing in regelgeving naar private normalisatienormen vindt een koppeling plaats tussen zelfregulering en wetgeving. Er wordt, met andere woorden, een link gelegd tussen privaat- en publiekrecht. In dit boek is de publiekrechtelijke status van deze normalisatienormen onderzocht, om vervolgens vast te kunnen stellen of de (grond) wettelijke bekendmakingsvoorschriften op deze normen van toepassing zijn en of deze in de praktijk ook worden toegepast. De auteur meent dat dit eerste wél het geval is en het laatste niet. Daarnaast is onderzocht wat de auteursrechtelijke status is van de 'verwezen' normalisatienormen. Artikel 11 Auteurswet sluit namelijk onder meer wetten en verordeingen uit van auteursrecht. Dit onderzoek is van belang omdat het NNI het auteursrecht voorbehoudt op de NEN-normen, waarvoor tot nu toe hoge prijzen worden berekend. Een dergelijk onderzoek naar de status van 'verwezen' normalisatienormen is in Nederland - in tegenstelling tot in Duitsland - tot op heden uitgebleven. Dit boek geeft een kritische rechtsvergelijkende analyse van de (juridische ) problemen die verwijzing naar normalisatienormen in regelgeving oproept. Show less