Vehicle emission control technology-- a correlation of emissions in relation to source

Imperial Users onl

Robust tuning procedures of dead-time compensating controllers

This paper describes tuning procedures for dead-time compensating controllers (DTC). Both stable and integrating processes are considered. Simple experiments are performed to obtain process models as well as bounds on the allowable bandwidth for stability. The DTC's used have few parameters with clear physical interpretation so that manual tuning is possible. Furthermore, it is shown how the DTC's can be made robust towards dead-time variations. </p

The struggle for western integration

The study deals with the military integration of Iceland into the Western Alliance, 1945-60. It focuses on several turning points in Iceland’s relations with the United States and NATO during the First Cold War: the debate over the withdrawal of U.S. troops in 1945-46; Iceland’s entry into NATO in 1949; the arrival of U.S. troops in 1951; the demand for the revocation of the U.S.-Icelandic Defence Treaty in 1956, and the stabilization in the bilateral relationship in 1959-60. It will be argued that two central theories capture the dynamics of Iceland’s relationship with the United States during this period. The national security thesis and the “Empire by Invitation” thesis. The purpose is to address four key problems. First, the study assesses the military importance of Iceland during this period. Secondly, it explores how ideological affinity, especially anti-Communism, shaped U.S.-Icelandic cooperation. Thirdly, it attempts to detect the international and domestic sources of Iceland’s policy toward the U.S. Finally, it examines the political forces that contested U.S. influence in Iceland

Microalgae production and maintenance optimization via mixed-integer model predictive control

This paper studies the joint production and maintenance scheduling in microalgae manufacturing systems comprised of multiple machines, which are subject to coupled production demand agreements and operational maintenance constraints. Namely, there are some microalgae production demands to be met over a given horizon, and the maintenance of each microalgae manufacturing unit must be done before a given deadline. Moreover, the number of units whose maintenance can be done simultaneously over the same day is limited, and the units that undergo maintenance cannot contribute to microalgae production during their maintenance day. To solve the considered problem, we design a mixed-integer nonlinear model predictive controller, which is implemented in two optimization stages. The former regards a mixed-integer model predictive control problem, while the latter considers a nonlinear model predictive control problem. The proposed approach allows us to decouple the mixed-integer and nonlinear parts of the whole problem, and thus provides more flexibility on the optimization solvers that can be employed. In addition, the first stage also evaluates the attainability of the demand agreements, and provides a mechanism to minimally adjust such constraints so that their satisfaction can be guaranteed at the second stage. The overall model predictive control approach is based on experimental data collected at VAXA Technologies Ltd., and the effectiveness of the proposed method is validated through numerical simulations including multiple manufacturing units and uncertainties.Juan Martinez-Piazuelo gratefully acknowledges the Universitat Politècnica de Catalunya and Banco Santander for the financial support of his predoctoral grant FPI-UPC. In addition, the authors would like to thank VAXA Technologies Ltd. as well as the project PID2020-115905RB-C21 (L-BEST) funded by MCIN/ AEI /10.13039/501100011033 for supporting this research.Peer ReviewedPostprint (published version

Territorial nationalism and Arctic geopolitics: Iceland as an Arctic Coastal state

This paper explores the cultural and political significance of being acknowledged and recognized as an “Arctic coastal state”. Using Iceland as a case study, we consider how coastal state status had grown in significance as the Arctic Ocean has been re-imagined more as a polar Mediterranean and less as a frozen desert. By drawing on Michael Billig’s work on banal nationalism and popular geopolitics, the manner in which the ideas and practices associated with a “coastal state” are reproduced in elite and everyday contexts. However, we conclude by noting that thus far this appeal to Iceland as “coastal state” has gained greater traction within the Icelandic Foreign Ministry and Parliament, and it remains to be seen whether it will have a more popular resonance with Icelandic citizens. Whatever the future, it is a timely reminder that terms such as “coastal state” are caught up in national and even circumpolar identity projects

Medieval Iceland, Greenland, and the New Human Condition: A case study in integrated environmental humanities

This paper contributes to recent studies exploring the longue durée of human impacts on island landscapes, the impacts of climate and other environmental changes on human communities, and the interaction of human societies and their environments at different spatial and temporal scales. In particular, the paper addresses Iceland during the medieval period (with a secondary, comparative focus on Norse Greenland) and discusses episodes where environmental and climatic changes have appeared to cross key thresholds for agricultural productivity. The paper draws upon international, interdisciplinary research in the North Atlantic region led by the North Atlantic Biocultural Organization (NABO) and the Nordic Network for Interdisciplinary Environmental Studies (NIES) in the Circumpolar Networks program of the Integrated History and Future of People on Earth (IHOPE). By interlinking analyses of historically grounded literature with archaeological studies and environmental science, valuable new perspectives can emerge on how these past societies may have understood and coped with such impacts. As climate and other environmental changes do not operate in isolation, vulnerabilities created by socioeconomic factors also beg consideration. The paper illustrates the benefits of an integrated environmental-studies approach that draws on data, methodologies and analytical tools of environmental humanities, social sciences, and geosciences to better understand long-term human ecodynamics and changing human-landscape-environment interactions through time. One key goal is to apply previously unused data and concerted expertise to illuminate human responses to past changes; a secondary aim is to consider how lessons derived from these cases may be applicable to environmental threats and socioecological risks in the future, especially as understood in light of the New Human Condition, the concept transposed from Hannah Arendt's influential framing of the human condition that is foregrounded in the present special issue. This conception admits human agency's role in altering the conditions for life on earth, in large measure negatively, while acknowledging the potential of this self-same agency, if effectively harnessed and properly directed, to sustain essential planetary conditions through a salutary transformation of human perception, understanding and remedial action. The paper concludes that more long-term historical analyses of cultures and environments need to be undertaken at various scales. Past cases do not offer perfect analogues for the future, but they can contribute to a better understanding of how resilience and vulnerability occur, as well as how they may be compromised or mitigated

Maritime activity in the High North : current and estimated level up to 2025 : MARPART Project Report 1

This report analyzes the current commercial and governmental activity in the sea regions north of the Polar Circle from the Northern Sea Route to the North West Passage. The study embraces sea and coastal areas of the North West of Russia, Northern Norway and around Svalbard, Iceland and Greenland. It includes an overview of types of vessels and other objects involved in different activities, and the volume of traffic connected to different types of activities, such as fisheries, petroleum, tourism, navy and research. Furthermore, this report estimates the maritime activity level in the area the next ten years, or until 2025, and the potential development of the regional preparedness system

Maritime activity and risk patterns in the High North : MARPART Project Report 2

This report provides a discussion on dominating risk factors, risk types and probability of unwanted incidents in the Arctic region. It also provides a coarse-grained evaluation of the potential consequences of different incidents in the northern sea areas of Russia, Norway, Greenland, and Iceland. The risk assessment build upon statistics on vessel activity, case studies of real incidents, and expert evaluation of defined situations of hazard and accident (DSHA). The evaluations of this study may serve as a platform for more detailed assessments, and as input for discussions on priority areas in respect to safety measures and emergency preparedness. In the Marpart Project, the risk assessments have a special role as input into the analyses of emergency management capabilities, and the need for special government efforts in cross-border cooperation