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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

[pt] MODELO DE OTIMIZAÇÃO PARA AVALIAÇÃO DO SUPRIMENTO DE GASOLINA E DIESEL NA REGIÃO NORDESTE DO BRASIL / [en] OPTIMIZATION MODEL FOR EVALUATING THE SUPPLY OF GASOLINE AND DIESEL IN THE BRAZIL S NORTHEAST REGION

THIAGO DIAS DE OLIVEIRA 07 April 2015 (has links)
[pt] O aumento expressivo no consumo de combustíveis no Brasil trouxe grandes desafios para a cadeia de suprimento no país. Ao longo dos últimos cinco anos (2009-2013), o mercado brasileiro de gasolina e diesel cresceu 62,8 porcento e 32,0 porcento, respectivamente. Porém, os investimentos em produção e infraestrutura não acompanharam este crescimento, tornando estes desafios cada vez maiores. Na região Nordeste do país, que é suprida majoritariamente por cabotagem, a infraestrutura para movimentação dos derivados de petróleo está aquém daquela necessária, trazendo ineficiências à cadeia de suprimentos e aumentando significativamente os custos envolvidos nas operações. Para avaliação do suprimento desta região, foi proposto um modelo de programação matemática que considera todas as restrições que impactam diretamente o suprimento de gasolina e diesel, identificando inclusive aquelas restrições que são ocasionadas por outros agentes da cadeia, como por exemplo, insuficiência de tancagem dos clientes, restrição de calados dos portos e elevadas taxas de ocupação dos portos públicos, aumentando os custos de sobrestadia. Para complementar a análise, alternativas para direcionamento de investimento dos distribuidores de forma eficiente, minimizando os custos da cadeia de suprimento, foram avaliadas. O modelo também foi utilizado na discussão dos níveis de serviço praticados pela Petrobras no atendimento da demanda de gasolina e diesel nos polos da região. O trabalho teve uma abordagem da cadeia de suprimento voltada para o planejamento tático, se mostrando como uma ferramenta eficiente para suporte à tomada de decisões. / [en] The significant increase of fuel consumption in Brazil has brought major challenges to the supply chain in the country. Over the last five years (2009- 2013), the Brazilian market for gasoline and diesel has increased 62.8 percent and 32.0 percent, respectively. However, investments in production and infrastructure have not kept up this growth, increasing the challenges. In the Northeast region of the country, which is supplied largely by coastal shipping, the infrastructure for the petroleum products movement falls short of what is needed bringing several inefficiencies to the supply chain and significantly increasing the costs involved in operations. To assess the supply of this region, a mathematical programming model was proposed which considers all the constraints that directly impact the supply gasoline and diesel, including identifying those constraints that are caused by other actors in the chain, such as insufficient costumer s tankage, draught restriction of ports and high occupancy rates of public ports, raising the cost of demurrage. To complement the analysis, alternative scenarios to allocate the distributor s investments efficiently were evaluated to minimize the costs of the supply chain. The proposed model was also used to discuss the service levels committed by Petrobras in meet the demand for gasoline and diesel at the region. The study had an approach to supply chain oriented for tactical planning, showing as an efficient tool to support decision making.
162

Detection and Analysis of Anomalies in Tactical Sensor Systems through Structured Hypothesis Testing / Detektion och analys av avikelser i taktiska sensorsystem genom strukturerad hypotesprövning

Ohlson, Fredrik January 2023 (has links)
The project explores the domain of tactical sensor systems, focusing on SAAB Gripen’s sensor technologies such as radar, RWR (Radar Warning Receiver), and IRST (InfraRed Search and Track). The study employs structured hypothesis testing and model based diagnostics to examine the effectiveness of identifying and isolating deviations within these systems. The central question addressed is whether structured hypothesis testing reliably detects and isolates anomalies in a tactical sensor system. The research employs a framework involving sensor modeling of radar, RWR, and IRST, alongside a sensor fusion model, applied on a linear target tracking model as well as a real target flight track obtained from SAAB Test Flight and Verification. Test quantities are derived from the modeled data, and synthetic faults are intentionally introduced into the system. These test quantities are then compared to predefined thresholds, thereby facilitating structured hypothesis testing. The robustness and reliability of the diagnostics model are established through a series of simulations. Multiple scenarios with varied fault introductions across different sensor measurements are examined. Key results include the successful creation of a tactical sensor model and sensor fusion environment, showcasing the ability to introduce and detect faults. The thesis provides arguments supporting the advantages of model based diagnosis through structured hypothesis testing for assessing sensor fusion data. The results of this research are applicable beyond this specific context, facilitating improved sensor data analysis across diverse tracking scenarios, including applications beyond SAAB Gripen. As sensor technologies continue to evolve, the insights gained from this thesis could offer guidance for refining sensor models and hypothesis testing techniques, ultimately enhancing the efficiency and accuracy of sensor data analysis in various domains. / Denna rapport undersöker området inom taktiska sensorsystem och fokuserar på SAAB Gripens sensorteknik, såsom radar, RWR (Radar Warning Receiver) och IRST (InfraRed Search- and Track). Studien använder strukturerad hypotesprövning och modellbaserad diagnostik för att undersöka effektiviteten av att identifiera och isolera avvikelser inom dessa system. Den centrala frågan som behandlas är om strukturerad hypotesprövning tillförlitligt upptäcker och isolerar avvikelser i ett taktiskt sensorsystem. För att tackla denna utmaning används sensormodellering av radar, RWR och IRST, tillsammans med en sensorfusionsmodell som appliceras på en linjär målspårningsmodell samt verklig målflygbana erhållen från SAAB. Testkvantiteter härleds från den resulterande datan, och syntetiska fel introduceras avsiktligt i systemet. Dessa testskvantiteter jämförs sedan med fördefinierade trösklar vilket lägger grunden för strukturerad hypotesprövning. Tillförlitligheten och pålitligheten hos diagnostikmodellen etableras genom en serie av simuleringar bestående av flera scenarier med varierade felintroduktioner över olika sensorinmätningar. Huvudresultat inkluderar skapandet av en taktisk sensormodell och en sensorfusionsmiljö, som visar förmågan att introducera och upptäcka fel på ett effektivt sätt. Avhandlingen ger argument som stödjer fördelarna med modellbaserad diagnostik genom strukturerad hypotestestning för bedömning av sensorfusionsdata. Resultaten av denna forskning är tillämpliga utanför detta specifika sammanhang, vilket underlättar förbättrad sensordataanalys över olika spårningsscenarier, inklusive applikationer bortom SAAB Gripen. I takt med att sensorteknologier fortsätter att utvecklas kan insikterna från denna avhandling ge vägledning för att förbättra sensormodeller och hypotestestningstekniker, vilket i slutändan förbättrar effektiviteten och noggrannheten för sensordataanalys inom olika områden.
163

Современные методики и оценка технико-тактических действий хоккеистов при вбрасывании шайбы : магистерская диссертация / Modern techniques and evaluation of technical and tactical actions of hockey players when throwing the puck

Деменьшин, Е. В., Demenshin, E. V. January 2018 (has links)
The master's thesis discusses and solves the issues of technical and tactical training of hockey players. The program and methods of improving the technical and tactical actions of athletes when throwing the puck in hockey. The efficiency of the applied technique is proved. / В магистерской диссертации рассматриваются и решаются вопросы технико-тактической подготовки хоккеистов. Разработана программа и методика совершенствования технико-тактических действий спортсменов при вбрасывании шайбы в хоккее. Доказана эффективность примененной методики.
164

Användningen av gaturum som katalysator för förändring : En fallstudie av Härnösand kommuns arbete i stadskärnan för ett minskat bilberoende / The use of street space as a catalyst for change : A case study of Härnösand municipality's work in the city center to reduce car dependency

Hagardt, Beatrice January 2023 (has links)
Bilen är fortfarande ett samhällsproblem som allt fler städer vill komma bort ifrån och istället värna om den mänskliga dimensionen. Gaturummen anses därför vara den plats i staden som ska leda förändringen, ritbordet och kartan är numera negligerade. Denna studie undersöker med hjälp av sex kvalitativa intervjuer Härnösands kommuns arbete med att reducera biltrafiken i gaturummet för att skapa ett gaturum för människor och minskad biltrafik. Resultatet visar att Street Moves är svaret på planeringens svårigheter i de centrala delarna av Härnösands bildominans, gestaltning och acceptans från medborgarna för att få legitimitet i att driva förändring i gaturummet. Slutsatsen är att arbetssättet med Street Moves är gynnsamt och eftersträvansvärt samtidigt som medborgarna som ett verktyg förblir kontradiktoriskt / The car has long been and is still a societal problem that more cities want to get away from and protect the human dimension instead. The street spaces are considered as places in the city that will lead to change to a more sustainable development, the drawing board and map are now neglected. This study examines Härnösand municipality's work to reduce car traffic in the street space to create spaces for people while reducing car traffic. Six qualitative interviews have been conducted. The result shows that Street Moves, a project that is the answer to the difficulties of planning in the city of Härnösand's to reduce car dependency, and to work with conformation and acceptance from citizens, to gain legitimacy in driving change in the street space. The conclusion is that the approach with Street Moves is beneficial and desirable, while citizens as a tool remain adversarial.
165

Tactical control of unmanned aerial vehicle swarms for military reconnaissance / Taktisk styrning av autonom och obemannad luftfarkostssvärm

Maxstad, Isak January 2021 (has links)
The use of unmanned aerial vehicles (UAVs) is well established in the military sector with great advantages in modern warfare. The concept of using UAV swarms has been discussed over two decades, but is now seeing its first real system used by the Israel defence forces. There is no exact definition what a swarm is, but it is proposed that it should satisfy the following three requirements. A swarm should have limited human control, the number of agents in a swarm should be at least three and the agents in the swarm should cooperate to perform common tasks. The complexity of controlling multiple autonomous UAVs gives way to the problem of how to take advantage of the operators cognitive and tactical abilities to control a swarm to effectively conduct military reconnaissance missions. The method of using behaviour trees as a control structure was derived from previous work in swarm systems. A behaviour tree is a structured way of organising and prioritising actions of autonomous systems. Behaviour trees are similar to finite state machines (FSMs) with the advantages of being modular, reactive, and with better readability. Three different behaviour trees with increasing complexity was created and simulated in the game engine Unity. A fourth more real life behaviour tree was created and used as a basis for discussing the strength and weaknesses of using behaviour trees against previous work. Using behaviour tree as a unifying structure for creating a swarm that integrates the tactical abilities of an operator with the strength of an autonomous swarm seems promising. The proposed method of using behaviour trees i suggested to be used as a platform for discussing the swarm desired functions and to create a common vision for both operators and engineers how a swarm should function. / Användning av drönare är väletablerad inom det militära och ger stora fördelar i dagens moderna krigsföring. Idén om att använda en svärm av drönare har diskuterats under de senaste två decennierna, men först nu sett sin första riktiga system som använts av Israels försvarsmakt. Det finns ingen exakt definition av vad en svärm är, men det har föreslagits att en svärm ska uppfylla de följande tre kraven. En svärm ska ha begränsad mänsklig interaktion, antalet agenter ska vara minst tre och svärmen ska samarbeta för att lösa gemensamma uppgifter. Svårigheterna med att styra en autonom svärm ger upphov till hur man ska utnyttja en operatörs kognitiva och taktiska förmåga för att styra en autonom drönarsvärm för att effektivt utföra militära spaningsuppdrag. Utifrån tidigare arbete inom styrning av svärmar verkade beteende träd som en lovande metod. Beteendeträd är ett strukturerat sätt att organisera och prioritera beteenden för ett autonomt system. Beteendeträd har många likheter med ändliga tillståndsmaskiner, men fördelarna att vara modulära, responsiva och mer lättläsliga. Tre olika beteendeträd med ökande komplexitet skapades och deras funktionalitet simulerades i Unity. Ett fjärde mer verklighetstroget beteendeträd skapades och användes som underlag för att diskutera beteendeträds styrkor och svagheter i jämförelse med tidigare arbeten. Användningen av beteendeträd för att förena den mänskliga operatören med det autonoma systemet verkar lovande. Den föreslagna metoden att använda beteendeträd för att styra en svärm är tänkt att användas som ett gemensamt underlag för att möjliggöra att operatörer och ingenjörer kan ha en gemensam bild hur en svärm ska fungera.
166

Collaborative applications used in a wireless environment at sea for use in Coast Guard Law Enforcement and Homeland Security missions

Klopson, Jadon E., Burdian, Stephen V. 03 1900 (has links)
Approved for public release, distribution is unlimited / This thesis analyzes the potential impact of incorporating wireless technologies, specifically an 802.11 mesh layer architecture and 802.16 Orthogonal Frequency Division Multiplexing, in order to effectively and more efficiently transmit data and create a symbiotic operational picture between Coast Guard Cutters, their boarding teams, Coast Guard Operation Centers, and various external agencies. Two distinct collaborative software programs, Groove Virtual Office and the Naval Postgraduate School's Situational Awareness Agent, are utilized over the Tactical Mesh and OFDM network configurations to improve the Common Operating Picture of involved units within a marine environment to evaluate their potential impact for the Coast Guard. This is being done to increase the effectiveness and efficiency of Coast Guard units while they carry out their Law Enforcement and Homeland Security Missions. Through multiple field experiments, including Tactical Network Topology and nuclear component sensing with Lawrence Livermore National Laboratory, we utilize commercial off the shelf (COTS) equipment and software to evaluate their impact on these missions. / Lieutenant Commander, United States Coast Guard / Lieutenant, United States Coast Guard
167

The disparity surrounding the integration of Joint Fires an argument for a Joint Fires Observer (Airborne) (JFO(A)) /

Phillippi, David M. January 2008 (has links)
Thesis (Master of Military Studies)-Marine Corps Command and Staff College, 2008. / Title from title page of PDF document (viewed on: Jan 12, 2010). Includes bibliographical references.
168

Building a simulation toolkit for wireless mesh clusters and evaluating the suitability of different families of ad hoc protocols for the Tactical Network Topology

Karapetsas, Konstantinos 03 1900 (has links)
Approved for public release, distribution is unlimited / Wireless mesh networking has emerged as the successor of the traditional ad hoc networks. New technological advances, the standardization of protocols and interfaces and the maturity of key components have made it possible for current mesh research groups to set goals that are really close to the world's expectations. The objective of this research is to design and implement a simulation toolkit for wireless mesh clusters that can be used as an additional performance evaluation technique for the Tactical Network Topology program of Naval Postgraduate School. This toolkit is implemented in the OPNET simulation environment and it incorporates various nodes running different ad hoc routing protocols. Furthermore, the investigation of a suitable combination of protocols for the Tactical Network Topology is achieved by creating scenarios and running a number of simulations using the mesh toolkit. / Captain, Hellenic Air Force
169

Analysis of hardware requirements for airborne tactical mesh networking nodes / An analysis of tactical mesh networking hardware requirements for airborne mobile nodes

Milicic, Gregory J. 03 1900 (has links)
Approved for public release, distribution is unlimited / Wireless mesh mobile ad hoc networks (MANETs) provide the military with the opportunity to spread information superiority to the tactical battlespace in support of network-centric warfare (NCW). These mesh networks provide the tactical networking framework for providing improved situational awareness through ubiquitous sharing of information including remote sensor and targeting data. The Naval Postgraduate School's Tactical Network Topology (TNT) project sponsored by US Special Operations Command seeks to adapt commercial off the shelf (COTS) information technology for use in military operational environments. These TNT experiments rely on a variety of airborne nodes including tethered balloon and UAVs such as the Tern to provide reachback from nodes on the ground to the Tactical Operations Center (TOC) as well as to simulate the information and traffic streams expected from UAVs conducting surveillance missions and fixed persistent sensor nodes. Airborne mesh nodes have unique requirements that can be implemented with COTS technology including single board computers and compact flash. / Lieutenant, United States Navy
170

Tactical decision aid for unmanned vehicles in maritime missions

Duhan, Daniel P. 03 1900 (has links)
Approved for public release; distribution is unlimited / An increasing number of unmanned vehicles (UV) are being incorporated into maritime operations as organic elements of Expeditionary and Carrier Strike Groups for development of the recognized maritime picture. This thesis develops an analytically-based planning aid for allocating UVs to missions. Inputs include the inventory of UVs, sensors, their performance parameters, and operational scenarios. Operations are broken into mission critical functions: detection, identification, and collection. The model output assigns aggregated packages of UVs and sensors to one of the three functions within named areas of interest. A spreadsheet model uses conservative time-speed-distance calculations, and simplified mathematical models from search theory and queuing theory, to calculate measures of performance for possible assignments of UVs to missions. The spreadsheet model generates a matrix as input to a linear integer program assignment model which finds the best assignment of UVs to missions based on the user inputs and simplified models. The results provide the mission planner with quantitatively-based recommendations for unmanned vehicle mission tasking in challenging scenarios. / Lieutenant, United States Navy

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