10 research outputs found

    Feasibility study for a numerical aerodynamic simulation facility. Volume 1

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    A Numerical Aerodynamic Simulation Facility (NASF) was designed for the simulation of fluid flow around three-dimensional bodies, both in wind tunnel environments and in free space. The application of numerical simulation to this field of endeavor promised to yield economies in aerodynamic and aircraft body designs. A model for a NASF/FMP (Flow Model Processor) ensemble using a possible approach to meeting NASF goals is presented. The computer hardware and software are presented, along with the entire design and performance analysis and evaluation

    Utility system integration and optimization models for nuclear power management.

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    Massachusetts Institute of Technology. Dept. of Nuclear Engineering. Thesis. 1973. Ph.D.Some pages numbered as leaves. Vita.Bibliography: p. 578-582.Ph.D

    Utility system integration and optimization models for nuclear power management

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    "Issued: June 1973."VitaAlso issued as a Ph. D. thesis by the first author and supervised by the second author, MIT, Dept. of Nuclear Engineering, 1973Includes bibliographical references (pages 578-582)A nuclear power management model suitable for nuclear utility systems optimization has been developed for use in multi-reactor fuel management planning over periods of up to ten years. The overall utility planning model consists of four sub-models: (1) Refueling and Maintenance Model (RAMM), (2) System Integration Model (SIM), (3) System Optimization Model (SOM), and (4) CORE Simulation and Optimization Models (CORSOM's). The SIM and SOM sub-models were developed in this study and are discussed in detail; full-scale computerized versions of each (SYSINT and SYSOPT, respectively) are evaluated as part of the methods development research. The RAMM generates feasible, mutually exclusive nuclear refueling-fossil maintenance schedules. These are evaluated in detail by the rest of the model. Using the Booth-Baleriaux probabilistic utility system model, the SIM integrates the characteristics of the utility's plants into a representation which meets the necessary operating constraints.Scheduling of system nuclear production and detailed fossil production is done for each time period (few weeks) making up the multi-year planning horizon. Utilizing a network programming model, the SOM optimizes the detailed production schedules of the nuclear units so as to produce the required system nuclear energy at minimum system cost. CORSOM's are utilized to optimize reload parameters (batch size and enrichment) and to generate the individual reactor fuel costs and nuclear incremental costs. These incremental costs are then used by the SOM's iterative gradient optimization technique known as the method of convex combinations. The SYSINT model is shown to be remarkably fast, performing the Booth-Baleriaux simulation for a single time period on a system with over 45 generating units in less than 2.5 seconds on an IBM-370 model 155 computer. SYSOPT converged to optimum solutions in roughly ten iterations.Immediate reduction of iterations by roughly half is estimated by merely increasing piecewise-linearization of the network objective function. Overall model computational requirements are limited by available CORSOM's, which require 99% of the computational effort (over 3 minutes per reactor per SOM iteration). Nuclear incremental costs (~ 0.8-1.6 /MWH)areshowntobelessthanfossilincrementalcosts(>2.0/MWH) are shown to be less than fossil incremental costs (> 2.0 /MWH) for the foreseeable future. Thus, nuclear power should always be operated so as to supply customer demands with a minimum use of the more expensive fossil energy. For the same reason, the lengthening of nuclear irradiation cycles (in terms of both energy and time) more than pays for itself by reducing the total cost of fossil replacement energy. Idealized nuclear production schedules yield constant nuclear incremental costs regardless of reactor unit and time. One of the key input parameters is the fossil thermal energy cost.M.I.T. DSR Project no. 72107Work Sponsored by Commonwealth Edison Company, Chicago, Illinoi

    Geophysical risk: earthquakes

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    Report on active and planned spacecraft and experiments

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    Information is presented, concerning active and planned spacecraft and experiments known to the National Space Science Data Center. The information included a wide range of disciplines: astronomy, earth sciences, meteorology, planetary sciences, aeronomy, particles and fields, solar physics, life sciences, and material sciences. These spacecraft projects represented the efforts and funding of individual countries as well as cooperative arrangements among different countries

    WATER SAFETY MANAGEMENT, LEGIONELLA PREVENTION AND RISK MANAGEMENT IN HOSPITALS: A FRAMEWORK FOR ESTATES AND FACILITIES MANAGEMENT IN ENGLAND

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    This study is the first to evaluate water safety and Legionella prevention from a management level perspective. It is an organisation’s duty to prevent any harm or risks potentially threatening the health of people. For that, certain processes are essential to be applied. They should be known by the people responsible and those, who are involved in any process serving to maintain health and safety, and to reduce known hazards. This thesis’s purpose is to create a significant contribution to knowledge by creating the first ever suggested framework for England. It makes a distinct and original contribution to knowledge as it is easy to understand and provides schemes and docu-ment templates for reference and for application. The specific aim of this research is to systematically identify the present situation of water safety and Legionella prevention in water systems in healthcare organisations, i.e. hospitals and hospital trusts in England. It seeks to create a framework guiding management processes to people re-sponsible to identify and better understand roles and processes to properly take action for the prevention of water system related infections caused by Legionella. The focus of the research lies in organisational structures from the point of view of Estates and Facilities Management. It anal-yses the current state of the process of Legionella prevention with a focus in England and with a different way of looking at the problem. In research papers the topic is neither very prevalent nor easily accessible at management levels. Methodology is built on a mixed methods research de-sign and a multilevel triangulation approach. An embedded design applies cases for analysis, that have been empirically collected during an exploratory first phase with cases in the UK, Germany and Switzerland. A consecutive country-specific phase fosuing the research more specific was applied for England. Data from interviews and documents was collected and analysed during the exploratory phase, which had a focus on taxonomy and to explore job descriptions and factors in hospitals that have a thematic connection to Legionella, risk management and water systems for the purpose of water safety management. This phase was also necessary to test the fluency of the procedures selected for data collection and verify and confirm the case strategy chosen. Re-search of the following phase collected and analysed data from interviews, a survey and docu-ments. The specific focus of this phase was to find patterns, define coding structures, build cate-gories, analyse and compare content by applying cycles of content analysis to find levels of ab-straction to create a draft version of a framework, which underwent a validation step in a final fo-cus group by experts in the field of risk management and water safety. Throughout the research process, the findings present a systematically reviewed and analysed picture of procedures of water safety management. It applies stakeholder analysis as well as pro-cess analysis, demonstrating levels of collaboration, risk management procedures, process man-agement, quality management, environmental management and knowledge management. The dissemination of the research’s output is a framework titled “Water safety management, Le-gionella prevention and risk management in hospitals: a framework for Estates and Facilities Man-agement in England”. It aims at closing the gap between theory and practice and complies with best practice. It translates given obligations into the professional field of Estates and Facilities Management and should be made available for transferring knowledge

    Scheduling dynamic positioned tankers with variable travel time for offshore offoading operations

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    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia de Automação e Sistemas, Florianópolis, 2015.A operação de campos de petróleo em alto mar implica na transferência de óleo que acumula em Unidades Flutuantes de Produção, Armazenamento e Descarregamento (FPSOs em inglês) para terminais em terra. Uma frota de Petroleiros Dinamicamente Posicionados (DPTs em inglês), ou navios aliviadores, é utilizada para a transferência de óleo das plataformas flutuantes até os terminais terrestres, onde depois o petróleo é transportado em grandes petroleiros ou por dutos até as refinarias. O escalonamento de uma frota de navios aliviadores, que minimiza os custos operacionais e que atenda às restrições do sistema, consiste em um problema complexo. Este trabalho propõe uma formulação em Programação Linear Inteira Mista (MILP em inglês) que avança em relação à trabalhos anteriores pela contabilização de tempos de viagem variáveis entre plataformas e terminais terrestres. As viagens dos navios aliviadores são modeladas como caminhos em um grafo direcionado tendo o terminal terrestre, plataformas flutuantes e pontos de controle como nós, enquanto os arcos representam os possíveis movimentos e operações de carregamento/descarregamento dos navios aliviadores. Do ponto de vista econômico, a frota de navios aliviadores deve ser escalonada para maximizar a produção de petróleo nas plataformas flutuantes enquanto minimiza os custos gerados pelas viagens. A combinação da formulação MILP com um solver constitui uma ferramenta para auxiliar os engenheiros na tomada de decisões. Este problema pode ser resolvido diariamente utilizando a estratégia de rolling-horizon para responder a eventos inesperados. No capítulo 1 apresentamos o problema do Planejamento do Suprimento de Petróleo que envolve desde a produção de óleo e gás nas plataformas até o atendimento da demanda do mercado com os subprodutos beneficiados nas refinarias. O escalonamento de navios aliviadores constitui um subproblema da cadeia produtiva de petróleo e possui uma importância tática dentro do planejamento das operações. No capítulo 2 discutimos alguns conceitos importantes no campo da otimização. Primeiro definimos o que é otimização e o que é um modelo de otimização utilizando como exemplo o Problema da Mochila. Em seguida, apresentamos o conceito de Programação Inteira (IP) e Programação Linear Inteira Mista (MILP) e fazemos uma breve discussão sobre algoritmos para a solução de IPs e MILPs. Também introduzimos o conceito de relaxação e sua relevância na solução de problemas de otimização. Uma seção é dedicada para a introdução de conceitos relacionados com problemas de escalonamento e roteamento e por último apresentamos alguns métodos de otimização dinâmica como o rolling-horizon e relax-and-fix. No capítulo 3, apresentamos primeiro uma formulação prévia do problema que considera os tempos de viagem entre as plataformas e os terminais terrestres como fixos e em seguida, propomos uma nova formulação que considera os tempos de viagem variáveis. Uma revisão da literatura é feita com o intuito de relacionar o modelo proposto com outros trabalhos. O capítulo termina com resultados teóricos obtidos a partir do novo modelo. No capítulo 4 desenvolvemos a relaxação Lagrangeana do problema que origina o problema Dual Lagrangeano. Em seguida, apresentamos os algoritmos utilizados para a solução do problema dual e finalizamos o capítulo desenvolvendo a decomposição da função Dual Lagrangeana que quebra a função dual em diversas funções, uma para cada navio aliviador e plataforma, permitindo assim computação paralela. No Capítulo 5 definimos uma instância exemplo com campos de petróleo, terminais terrestres e navios aliviadores, no qual as análises computacionais são feitas. A primeira análise consiste em comparar os limites obtidos pela relaxação Lagrangeana e a relaxação linear do problema. Os métodos do subgradiente e de geração de restrições sob demanda foram utilizados para a solução do problema Dual Lagrangeano. Em seguida, comparamos a solução estática, onde o problema é resolvido para todo o horizonte de planejamento, com a solução dinâmica obtida utilizado as heurísticas de rolling-horizon e relax-and-fix. Estas em geral fornecem soluções sub-ótimas mas respondem de forma satisfatória às grandes instâncias e incertezas do problema. Fechando o capítulo, a estratégia de rolling-horizon é avaliada em um simulador que gera perturbações para variáveis do modelo. No capítulo 6 concluímos a dissertação com uma análise geral e contribuições do trabalho e propomos algumas direções para pesquisas futuras. Abstract : The logistics of operating oil fields off the coast entails transferring oil that accumulates in Floating Production Storage and Offloading Units (FPSOs) to onshore terminals. A fleet of Dynamically Positioned Tankers (DPTs), or shuttle tankers, is deployed for transferring oil from the floating platforms to onshore terminals, where the oil is transported in large tanker ships or by pipelines to refineries. The scheduling of a fleet of shuttle tankers that minimizes the operating costs while satisfying the system constraints consists of a complex problem. To this end, this work proposes a formulation in Mixed-Integer Linear Programming (MILP) that advances previous works by accounting for variable time travel between floating platforms and the onshore terminal. The trips of the shuttle tankers are modeled as paths in a directed graph having the onshore terminal, floating platforms, and control points as nodes and arcs representing possible moves and offloading operations for the shuttle tankers. As a business case, the fleet of shuttle tankers should be scheduled to maximize oil production from the floating platforms while factoring in the transportation costs. The combination of the MILP formulation with an optimization solver constitutes a tool to aid operations engineers in making advised decisions. This formulation can be systematically solved daily in a rolling-horizon framework to respond to unanticipated events

    Algorithms and Applications for non-coding RNAs in Aging

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    Gene expression is a complex molecular process governing fate and function of most eukaryotic cells. The fundamental mechanism, namely that genetic material of a cell is compactly stored on chromosomal DNA and at times being transcribed into messenger-RNA to facilitate on-demand protein biosynthesis, is widely known. However, the interplay of biochemical regulatory pathways underlying an individual’s disease phenotype development remains incompletely understood. Intriguingly, the ∼ 20.000 protein-coding genes only account for 2% of the human genome, triggering profound questions on the purpose of remaining segments. In recent years it became apparent that non-coding RNAs essentially tune the observed gene expression circuits. In particular the small non-coding RNAs such as microRNAs, turned out to be regulatory players by switching on and off protein translation of target messenger-RNAs. Several thousand mammalian microRNAs have been discovered so far but little is known about their impact on the transcriptome, which likely depends on contextual variables like cell type identity, cellular and tissue environment or phase of activation. Previous efforts demonstrated that gene expression programs in human and mouse undergo gradual changes along the life trajectory with amplification at higher ages. In parallel, age-related diseases are currently accumulating in our globally aging population, posing a serious challenge to our society and healthcare systems. Neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease show steadily rising incidence rates with several million people already affected. Both are caused by pathological protein accumulation in selectively vulnerable neurons and brain regions. Notably, these neurological disorders do not appear all of a sudden in an individual but are believed to originate after long asymptomatic phases of subtle aberrant changes on the cellular level, turning early diagnosis into an intricate affair. Yet, no single comprehensive model to explain aging associated changes in gene expression exists and certainly any such model must take into account the role of microRNAs and other important non-coding RNAs. With the advent of ultra-high-throughput sequencing techniques and unprecedented computational power, the screening of microRNAs and their targets from human biofluids and tissues became not only affordable but scalable. To deal with the increasing complexity of molecular studies, novel bioinformatics-driven approaches are needed to generate reproducible and comprehensive conclusions from large-scale data sets. Here, the role of small non-coding RNAs in governing gene expression changes observed in complex age-related diseases is explored with the aid of new methods and databases as well as several thousand RNA profiling samples. This cumulative doctoral thesis comprises eight peer-reviewed publications. Basic research covers a comprehensive review on most target prediction tools and a novel experimental and computational workflow for microRNA-target pathway identification. In addition, with miRPathDB 2.0 the so-far largest database on enriched microRNA pathways for human and mouse is presented. Moreover, the new versatile web tool miEAA 2.0 allows rapid annotation of statistically enriched molecular properties and functions for large lists of microRNAs from ten species. The lessons learned from web-based tool development were condensed in an invited summary and survey article on scientific web server availability along with best practices for developers. The here presented toolkit was used in three applied research studies to investigate the association between microRNAs and their target pathways in the context of aging as well as the to date largest Parkinson’s disease biomarker discovery framework. Circulating microRNAs obtained low-invasively from whole-blood samples bear diagnostic and prognostic value in Alzheimer’s and Parkinson’s disease patients, which was discovered using machine learning models. Furthermore, selected microRNA families were found to systematically target entire signaling pathways as to effectively silence gene expression. Indeed, these pathways are affected in prevalent neurodegenerative disorders. Taken together, the published candidate signatures and validated targets are pivotal for subsequent experimental perturbation in microRNA or gene knockout studies. In future efforts, large-scale single-cell studies will be required to further dissect disease and cell-type specificity of aging disease biomarker candidates and their long-term effect on gene expression, possibly indicating early neuropathological hallmarks.Genexpression ist ein komplexer molekularer Prozess, der das Überleben und die Funktion der meisten eukaryotischen Zellen entscheidend beeinflusst. Der zugrunde liegende Mechanismus, nämlich, dass das genetische Material einer Zelle kompakt in chromosomaler DNA vorliegt und je nach Bedarf in messenger-RNA zur Proteinbiosynthese genutzt wird, ist weitgehend bekannt. Allerdings ist das Zusammenspiel der regulatorischen Pfade im Hintergrund der phenotypischen Veränderungen von erkrankten Individuen nur wenig verstanden. Interessanterweise machen die fast 20.000 protein-kodierenden Gene nur in etwa 2% des menschlichen Erbgutes aus. In den letzten Jahren hat man festgestellt, dass nicht-kodierende RNAs eine essentielle Rolle bei der Einstellung der beobachteten Genexpressionsschaltkreise spielen. Insbesondere kleine nicht-kodierende RNAs wie microRNAs, stellten sich als zuvor unterschätzte regulatorische Einheiten heraus, die die Translation von Ziel-messenger-RNA in Proteine an und ausschalten. Mehrere tausend microRNAs wurden bisher bei Säugetieren entdeckt, trotzdem ist immer noch wenig über ihren Einfluss auf das Transkriptom bekannt, ein Zusammenhang der wahrscheinlich vom Kontext wie Zelltypidentität, dem zelluären Umfeld sowie dem umgebenden Gewebe, und den Aktivierungsphasen abhängt. Frühere Forschungsarbeiten haben bereits gezeigt, dass das Genexpressionsprogramm im Menschen und in der Maus sukzessiven Änderungen im Laufe des Lebens unterworfen ist, welche sich im höheren Alter verstärken. Zur gleichen Zeit akkumulieren Fälle von altersbedingten Krankheiten in unserer immer älter werdenden, globalen Population, was ernstzunehmende Herausforderungen für unsere Gesellschaft sowie unser Gesundheitssystem mit sich bringt. Neurodegenerative Krankheiten wie Morbus Alzheimer und Morbus Parkinson zeigen eine kontinuierlich ansteigende Inzidenz, wobei bereits mehrere millionen Menschen weltweit betroffen sind. Besonders für diese Krankheiten ist, dass sie bei einem Menschen nicht spontan oder plötzlich entstehen, sondern vermutlich nach langer Zeit der asymptomatischen Phase aufgrund schleichender, abnormaler Veränderungen auf zellulärer Ebene entstehen, was eine frühe Diagnose überaus schwierig gestaltet. Bisher existiert noch kein verständliches Modell das die altersassoziierten Veränderungen der Genexpression erklären kann, wobei jedes darauf ausgerichtete Modell mit Bestimmtheit die Rolle der microRNAs und anderen wichtigen nicht-kodierenden RNAs zwangsläufig in Betracht ziehen muss. Mit dem Aufkommen der Sequenzierung im Ultrahochdurchsatzverfahren und der unübertroffenen Leistung moderner Computersysteme, wurde die Untersuchung von microRNAs und ihren Zielgenen anhand von Proben menschlicher Flüssigkeiten und Geweben nicht nur möglich gemacht, sondern kann entsprechend hochskaliert werden. Um mit der zunehmenden Komplexität molekularer Studien Schritt zu halten, braucht es neue Ansätze der Bioinformatik um reproduzierbare und nachvollziehbare Schlüsse aus großen Datensätzen gewinnen zu können. Im Rahmen dieser Arbeit wurden kleine nicht-kodierende RNAs hinsichtlich ihrer Rolle der Genregulation in komplexen altersbedingten Krankheiten anhand neuer Methoden und Datenbanken sowie mehreren tausend Proben der RNA-Sequenzierung untersucht. Diese kumulative Dissertationsarbeit umfasst acht von unabhängigen Experten begutachtete (peer-reviewed), wissenschaftliche Publikationen. Die Grundlagenforschung enthält einen umfassenden Übersichtsartikel zu fast allen Methoden der Vorhersage von microRNA Zielgenen sowie ein neuartiges Protokoll bestehend aus Labormethoden und computergestützen Berechnungen zur Identifikation von durch microRNAs regulierte Genpfade. Zusätzlich wird mit miRPathDB 2.0 die bisher größte Datenbank zu signifikant angereicherten microRNA Zielpfaden präsentiert. Des Weiteren, bietet die neue und vielseitige, web-basierte Software miEAA 2.0 die Möglichkeit der rasanten Annotation statistisch angereicherter, molekularer Eigenschaften sowie bekannter Funktionen einer gegebenen Liste an microRNAs von zehn Spezies. Die durch web-basierte Softwareentwicklung zuvor angelernten Fähigkeiten sowie daraus resultierende Empfehlungen für nachfolgende Entwickler wurden kurz und bündig in einem eingeladenen Übersichtsartikel zum Thema Verfügbarkeit wissenschaftlicher Software im Internet veröffentlicht. Die hier präsentierten Werkzeuge wurden gezielt in drei Studien zur angewandten Forschung genutzt um die Assoziation zwischen microRNAs und ihren Zielpfaden im Kontext der allgemeinen Altersforschung sowie im Rahmen der bisher größten Studie zur Entdeckung von Biomarkern der Parkinson Krankheit zu untersuchen. Im Blutkreislauf zirkulierende microRNAs, die anhand von Vollblutproben extrahiert wurden, zeigen diagnostisches und prognostisches Potential bei Alzheimer und Parkinson Patienten, was mit Methoden des maschinellen Lernens entdeckt werden konnte. Überdies konnte herausgefunden werden, dass bestimmte microRNA Familien systematisch Signalwege blockieren können, um die Genexpression herunterzufahren. Tatsächlich sind diese Pfade auch in neurodegenerativen Krankheiten betroffen. Insgesamt sind die hier publizierten Signaturen von Kandidaten-microRNAs und einiger validierter Zielgene herausragend dazu geeignet in weiteren Studien anhand von gezielter Ausschaltung im Labor genauer untersucht zu werden. In zukünftigen Forschungsprojekten sollten groß angelegte Untersuchungen vieler einzelner Zellen im Vordergrund stehen, um zu verstehen wie spezifisch für Krankheit oder Zelltyp die hier genannten Biomarker-Kandidaten für altersbedingte Krankheiten sind. Auch wird es wichtig sein die Langzeiteffekte von dysregulierten microRNAs auf die Genexpression zu verstehen, die möglicherweise frühzeitig neuropathologische Kennzeichen widerspiegeln

    African Handbook of Climate Change Adaptation

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    This open access book discusses current thinking and presents the main issues and challenges associated with climate change in Africa. It introduces evidences from studies and projects which show how climate change adaptation is being - and may continue to be successfully implemented in African countries. Thanks to its scope and wide range of themes surrounding climate change, the ambition is that this book will be a lead publication on the topic, which may be regularly updated and hence capture further works. Climate change is a major global challenge. However, some geographical regions are more severly affected than others. One of these regions is the African continent. Due to a combination of unfavourable socio-economic and meteorological conditions, African countries are particularly vulnerable to climate change and its impacts. The recently released IPCC special report "Global Warming of 1.5º C" outlines the fact that keeping global warming by the level of 1.5º C is possible, but also suggested that an increase by 2º C could lead to crises with crops (agriculture fed by rain could drop by 50% in some African countries by 2020) and livestock production, could damage water supplies and pose an additonal threat to coastal areas. The 5th Assessment Report produced by IPCC predicts that wheat may disappear from Africa by 2080, and that maize— a staple—will fall significantly in southern Africa. Also, arid and semi-arid lands are likely to increase by up to 8%, with severe ramifications for livelihoods, poverty eradication and meeting the SDGs. Pursuing appropriate adaptation strategies is thus vital, in order to address the current and future challenges posed by a changing climate. It is against this background that the "African Handbook of Climate Change Adaptation" is being published. It contains papers prepared by scholars, representatives from social movements, practitioners and members of governmental agencies, undertaking research and/or executing climate change projects in Africa, and working with communities across the African continent. Encompassing over 100 contribtions from across Africa, it is the most comprehensive publication on climate change adaptation in Africa ever produced

    УСТОЙЧИВО РАЗВИТИЕ И СОЦИАЛНО- ИКОНОМИЧЕСКА КОХЕЗИЯ ПРЕЗ XXI ВЕК – ТЕНДЕНЦИИ И ПРЕДИЗВИКАТЕЛСТВА

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    Международната научно-практическа конференция е организирана в изпълнение проект НФ-2-2021 „Устойчиво развитие и социално-икономическа кохезия през XXI век – тенденции и предизвикателства“, финансиран със средства по Наредба на МОН за насърчаване на научно-изследователската дейнос
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