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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.
61

Brukarinflytande inom LSS : En intervjustudie om personalens upplevelser av brukarinflytande på verksamhetsnivå / User influence within LSS : An interview study of the staff's experiences of user influence at the organizational level

Ruka, Ejla, Ruka, Eljesa January 2022 (has links)
Syftet med studien är att undersöka personalens upplevelser av att möjliggöra brukarinflytande på verksamhetsnivå inom LSS. Inflytande på verksamhetsnivå innebär att kunna påverka beslut som verksamheten handhar med. Områden som studien har sitt fokus på är aktiviteter som genomförs på fritiden och att förändra lokaler på boendet. Det som arbetet kommer att belysa är hur personalen arbetar för att ge brukaren inflytande, samt vilka svårigheter och begränsningar personalen upplever med att tillgodose brukarens önskemål om aktiviteter och lokalanpassning. I resultatet av denna studie framgår det att svårigheter som bristande engagemang påverkar personalens möjligheter med att uppnå brukarinflytande. Det framgår även i resultatet att personalen upplever sitt handlingsutrymme begränsat med att tillgodose brukarens önskemål. De element som utgör en begränsning i personalens handlingsutrymme är främst brukarnas ekonomi, bemanning och arbetsschemat. / The purpose of the study is to investigate the staff’s experiences of enabling user influence at the organizational level within LSS. Influence at the organizational level means being able to affect decisions that the o handles. Areas that the study focuses on are activities that are implemented in leisure time and changing premises at the accommodation. What the work will emphasize on is how the staff works to give the user influence, and what difficulties and limitations the staff experience in satisfying the user’s desires for activities and local adaptation. The results of this study show that difficulties such as lack of commitment affect the staff’s opportunities to achieve user influence. It also appears from the results that the staff experience their room for maneuver limited in satisfying the user’s desires. The elements that constitute a limitation in the staff’s room for maneuver are mainly the users’ finances, staffing and work schedule.
62

Using Augmented Reality For Studying Left Turn Maneuver At Un-signalized Intersection And Horizontal Visibility Blockage

Moussa, Ghada 01 January 2006 (has links)
Augmented reality "AR" is a promising paradigm that can provide users with real-time, high-quality visualization of a wide variety of information. In AR, virtual objects are added to the real-world view in a real time. Using the AR technology can offer a very realistic environment for driving enhancement as well as driving performance testing under different scenarios. This can be achieved by adding virtual objects (people, vehicles, hazards, and other objects) to the normal view while driving in a safe controlled environment. In this dissertation, the feasibility of adapting the AR technology into traffic engineering was investigated. Two AR systems; AR Vehicle "ARV" system and Offline AR Simulator "OARSim" system were built. The systems' outcomes as well as the on-the-road driving under the AR were evaluated. In evaluating systems' outcomes, systems were successfully able to duplicate real scenes and generate new scenes without any visual inconsistency. In evaluating on-the-road driving under the AR, drivers' distance judgment, speed judgment, and level of comfort while driving were evaluated. In addition, our systems were used to conduct two traffic engineering studies; left-turn maneuver at un-signalized intersection, and horizontal visibility blockage when following a light truck vehicle. The results from this work supported the validity of our AR systems to be used as a surrogate to the field-testing for transportation research.
63

Design, Modeling, Guidance And Control Of A Vertical Launch Surface To Air Missile

Tekin, Raziye 01 September 2010 (has links) (PDF)
The recent interests in the necessity of high maneuverability and vertical launching triggered namely the unconventional control design techniques that are effective at high angle of attack flight regimes. For most of missile configurations, this interest required thrust vector control together with conventional aerodynamic control. In this study, nonlinear modeling and dynamical analysis of a surface to air missile with both aerodynamic and thrust vector control is investigated. Aerodynamic force and moment modeling of the presented missile includes the challenging high angle of attack aerodynamics behavior and the so called hybrid control, which utilizes both tail fins and jet vanes as control surfaces. Thrust vector and aerodynamic control effectiveness is examined during flight envelope. Different autopilot designs are accomplished with hybrid control. Midcourse and terminal guidance algorithms are implemented and performed on target sets including maneuverable targets. A different initial turnover strategy is suggested and compared with standard skid-to-turn maneuver. Comparisons of initial roll with aerodynamic and thrust vector control are examined. Afterwards, some critical maneuvers and hybrid control ratio is studied with a real coded genetic algorithm. Rapid turnover for low altitude targets, intercept maneuver analysis with hybrid control ratio and lastly, engagement initiation maneuver optimization is fulfilled.
64

Tracking military maneuver training disturbance with low cost GPS devices

Denker, Phillip Michael January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Stacy L. Hutchinson / Military training lands are a vital resource for national security and provide crucial habitat for a number of threatened and endangered species. Military land managers must manage the land in accordance with federal environmental policy and regulation, while simultaneously providing the lands needed for training military forces. Off road maneuver training can cause significant environmental damage including removal of vegetation, compaction of soils, increased erosion, loss of habitat, and degradation of the landscape to a point of not being useful for continued military training. Various techniques have been developed to help the military land managers determine a sustainable training level for the landscape. Many of these techniques have limitations in the spatial resolution of data collected and the ability to provide timely and accurate assessments of training disturbance. Advancements in GPS and GIS technology over the past two decades have shown the potential to fill this knowledge gap. In this study low cost civilian off the shelf (COTS) GPS devices were accuracy tested to determine their capability to provide reliable and accurate military vehicle locations during training (1.93 m CEP, 4.625m 2dRMS). The GPS data collected from COTS devices on three battalion training exercises at Fort Riley, KS were processed in a GIS and statistically analyzed to compare and contrast several off road maneuver metrics (speed, turning radius, distance traveled) by vehicle type tracked, and by platoon in order to determine if units or vehicle types could reliably explain the variation in these metrics. Lastly, a method of mapping the relative environmental disturbance was developed and mapped for the same data sets. Wheel sinkage was used as a measure of disturbance, it was calculated at each GPS point based on vehicle type and soil conditions then mapped in using a fishnet grid for Fort Riley, Kansas.
65

Methods for Improving Radar Maneuver Detection for Tangentially Moving Targets

Ali, Qurban 21 February 2017 (has links) (PDF)
This master thesis has been done in the field of Advanced Driver Assistance Systems and presents a method to assist cross traffic at road junctions. An accurate tracking of crossing objects is necessary in order to assist traffic at road junctions. At Continental, the stable tracking of crossing objects is available, but the system still gives false alarms for non-colliding objects (e.g. Target Braking at crossroads). Hence the main focus of this thesis is on the reduction of false alarms for non colliding objects. Radar based Maneuver Detection function has been developed for Crossing Emergency Brake Assist system, which uses radar measurement parameters to detect the maneuvering of target objects in order to differentiate between collision and non-collision cases. Different crossing scenarios have been created in a Matlab environment and the algorithm is tested. Secondly, the algorithm is tested by using the measurement data from real recordings and evaluation is made. The proposed algorithm has reliably detected the non-collided objects (in normal cases) and helped in reducing the false alarm rate significantly.
66

Development of an Intuitive Grader Control

Forsell, Hanna, Åkebäck, Malin January 2012 (has links)
This project has been carried out in cooperation with Volvo Construction Equipment. A new control intended to give an intuitive understanding for the new generation of operators of how to handle the motor grader has been developed. The project includes parts of the development process, idea to finished concept. The project started with a thorough study of the functions of motor graders not only those built by Volvo but also those from the biggest competitors. Interviews were made with operators about today’s and future controls of graders. In comparison the competitors seem to offer better controls both from ergonomic and cognitive points of view. Hitherto too little interest has been focused by design engineers in problems of the operators. Operators are exposed to wear and tear when driving the graders and they also have difficulties driving the machines all because of the design of the manoeuvring device. From the start to the final concept a great variety of people has been involved in this project e.g. young and old operators, scientists and constructors resulting in a large spread of ideas. The final concept is a new thinking control with respect to the combination of functionality, ergonomics and intuitivety. / Detta projekt har gjorts i samarbete med Volvo Construction Equipment. En ny kontroll har utvecklats som syftar till att ge en intuitiv förståelse för nästa generations väghyvelförare om hur väghyveln hanteras. Projektet inkluderar delar av designprocessen, idé till färdigt koncept. Projektet inleddes med en grundlig studie av väghyvelns funktioner, inte bara de som Volvo tillhandahåller utan även konkurrenternas. Intervjuer hölls med operatörer med frågor om dagens manövrering och framtida lösningar. I jämförelse förefaller det som att konkurrenterna tillhandahåller bättre lösningar på kontrollen ur ergonomiska och kognitiva perspektiv. Tidigare har de problem som operatören upplever inte varit i fokus i produktutvecklingsprocessen. Operatörer riskerar förslitningsskador när de kör väghyveln. De har, på grund av utformningen av styrenheten, även svårigheter att manövrera väghyveln samtidigt som de kör. Redan från start har en stor variation av människor varit inblandade i projektet t.ex. yngre och äldre förare, forskare och konstruktörer. Detta har resulterat i en stor spridning av idéer. Slutkonceptet är en nytänkande kontroll med avseende på kombination av funktionalitet, ergonomi och intuitivitet.
67

Physics based prediction of aeromechanical loads for the UH-60A rotor

Marpu, Ritu Priyanka 12 April 2013 (has links)
Helicopters in forward flight experience complex aerodynamic phenomena to various degrees. In low speed level flight, the vortex wake remains close to the rotor disk and interacts with the rotor blades to give rise to blade vortex interaction phenomena. In high speed flight, compressibility effects dominate leading to the formation of shocks. If the required thrust is high, the combination of high collective pitch and cyclic pitch variations give rise to three-dimensional dynamic stall phenomena. Maneuvers further exacerbate the unsteady airloads and affect rotor and hub design. The strength and durability of the rotor blades and hub components is dependent on accurate estimates of peak-to-peak structural loads. Accurate knowledge of control loads is important for sizing the expensive swash-plate components and assuring long fatigue life. Over the last two decades, computational tools have been developed for modeling rotorcraft aeromechanics. In spite of this progress, loads prediction in unsteady maneuvers which is critical for peak design loads continues to be a challenging task. The primary goal of this research effort is to investigate important physical phenomena that cause severe loads on the rotor in steady flight and in extreme maneuvers. The present work utilizes a hybrid Navier-Stokes/free-wake CFD methodology coupled to a finite element based multi-body dynamics analysis to systematically study steady level and maneuvering flight conditions. Computational results are presented for the UH-60A rotor for a parametric sweep of speed and thrust conditions and correlated with test data at the NFAC Wind Tunnel. Good agreement with test data has been achieved using the current methodology for trim settings and integrated hub loads, torque, and power. Two severe diving turn maneuvers for the UH-60A recorded in the NASA/Army Airloads Flight Tests Database have also been investigated. These maneuvers are characterized by high load factors and high speed flight. The helicopter experiences significant vibration during these maneuvers. Mean and peak-to-peak structural loads and extensive stall phenomena including an advancing side stall phenomena have been captured by the present analyses.
68

Close Air Support i moderna operationer

Nellsjö, Jonas January 2008 (has links)
De svenska insatsförbanden anpassas för de konflikter som är normgivande idag. Konceptuellt innebärdetta att doktriner och metoder måste utvecklas för att möta utvecklingen på dagens stridsfält. Denkonceptuella utvecklingen är förhållandevis billig jämfört med den tekniska, vilket innebär attförmågeutvecklingen mer anpassas till de materiella förutsättningarna som råder. Plattformar för CloseAir Support symboliserades under 80- och 90-talet av tungt beväpnade och särskilt anpassade flygplanoch helikoptrar som verkade i nära anslutning till markförbandens strid. Idag representeras dessaplattformar av andra flygsystem som sedan tidigare är utvecklade utifrån andra kravprofiler. Dennaobservation ligger till grund för undersökningen och formulerar därmed uppsatsens problem.Har innebörden av konceptet Close Air Support på senare tid förändrats och på så vis öppnat förandra typer av flygsystem att utöva detta koncept?Uppsatsens syfte är att undersöka hur Close Air Support tillämpats under tre moderna operationer föratt därmed finna orsaker till hur konceptet utvecklats till vad det representerar idag. Dessutom syftaruppsatsen till att klarlägga begreppets innebörd och därmed bidra med kunskap inom konceptet förClose Air Support.Undersökningen analyserar Close Air Support historiska ursprung och teorierna bakom kombineradevapen. Denna analys lägger grunden till den fallstudie som omfattar tre militära operationergenomförda efter 1990. Studien fokuseras mot samordning, plattformar och operativ och taktisk effekt.Avslutande diskussion påvisar att samordning av Close Air Support tillämpats olika under de studeradeoperationerna. De förutsättningar som råder för dagens konflikter möjliggör att användningsområdenför olika vapensystem kan utökas. Detta är en av förklaringarna till varför andra typer avstridsflygsystem idag utnyttjas för Close Air Support. Studien har visat att CAS som koncept inteförändrats. Däremot har Close Air Support tillämpats olika beroende på de operativa förutsättningarnasom rådde inför respektive operationUppsatsen föreslår tre områden inom ämnet som kan vara föremål för djupare analys. / The Swedish Armed Forces are transforming to be able to conduct military operations in today’sstandard conflicts. To meet the demands that the new type of conflict represents the transformationrequires a development of new doctrines and tactical manuals. .Developments of new weapon systems are proportionately much more expensive than conceptualdevelopments. The armed forces’ combat capability must be adapted to existing military technologicalconditions. During the 1980s and 1990s Close Air Support aircrafts were represented by heavily armedand armoured fixed- and rotary-wing aircrafts which carried out CAS missions in close proximity tofriendly forces. These CAS platforms are today, more or less, represented by traditional fighter andstriker aircrafts. This observation will form the basis of this research and thereby formulate thescientific question.Has the significance of Close Air Support been changed and is it therefore made it possible to useother combat aircrafts for Close Air Support missions?The purpose of this thesis is to examine how Close Air Support has been put in practise in threemodern operations and to ascertain how this has developed the concept to what it is today.Furthermore the thesis will also clarify the significance of the concept and thereby contribute withknowledge to the concept of Close Air Support.The research will analyze the concept’s historical origin and the theory behind combined arms. Thisanalysis will form the basis for the following case studies, which comprise three military operationscarried out after 1990. The research will focus on coordination, platforms and operational and tacticaleffects.The final discussion will show that coordination of CAS has been executed differently during the threestudied operations. Today’s conflicts make it possible to use weapon systems in an extended role. Thiswill explain why different combat aircraft could be used in a CAS role. The research shows that theCAS concept hasn’t changed. However, CAS has been performed in different ways depending on theoperational circumstances within each operation.The thesis suggests three new research areas within the subject that could be appropriate for furtherexaminations. / Avdelning: ALB - Slutet Mag 3 C-upps. Hylla: Upps. ChP 06-08
69

Robust Motion Planning in the Presence of Uncertainties using a Maneuver Automaton

Topsakal, Julide Julie 18 April 2005 (has links)
One of the basic problems which have to be solved by Unmanned Automated Vehicles (UAV) involves the computation of a motion plan that would enable the system to reach a target given a set of initial conditions in presence of uncertainties on the vehicle dynamics and in the environment. Recent research efforts in this area have relied on deterministic models. To address the problem of inevitable uncertainties, a low-level control layer is typically used to ensure proper robust trajectory tracking. Such decision-tracking algorithms correct model disturbances a posteriori, while the whole movement planning is done in a purely deterministic fashion. We argue that the decision making process that takes place during movement planning, as performed by experienced human pilots, is not a purely deterministic operation, but is heavily influenced by the presence of uncertainties and reflects a risk-management policy. This research aims at addressing these uncertainties and developing an optimal control strategy that would account for the presence of system uncertainties. The underlying description of UAV trajectories will be based on a modeling language, the Maneuver Automaton, that takes into full account the vehicle dynamics, and hence guarantees flyable and trackable paths and results in a discretized solution space. Two optimal control problems, a nominal problem omitting uncertainties and a robust problem addressing the presence of uncertainties, will be defined and compared throughout this work. The incorporation of uncertainties, will ensure that the generated motion planning policies will maximize the probability to meet mission goals, weighing risks against performance.
70

Pansarvärnshelikoptrar : Ett instrument för manöverkrigföring? / Anti-tank helicopters : A means for maneuver warfare?

Ekstedt, Anders January 2012 (has links)
Mellan år 1987 och 2000 fanns ett beväpnat helikopterförband inom arméflyget. Dessa två pansarvärnshelikopterkompanier användes för att bekämpa stridsfordon. Efter nedläggningen har Sverige inte haft en helikopter med beväpning för annat än egenskydd. Uppsatsen syftar till att utifrån William S. Linds teori om manöverkrigföring utvärdera om pansarvärnshelikopterkompanierna framgångsrikt bidrog till att besegra motståndaren. Det framkommer att pansarvärnshelikopterkompaniernas taktik väl stämmer överrens med Linds teori vilket pekar på att bestyckade helikoptrar är ett mycket användbart instrument inom manöverkrigföringen. / Between 1987 and 2000 there was an armed helicopter unit in the Swedish armed forces. These two anti-tank helicopter companies where used to destroy armored vehicles. After the companies disbandment there has been no helicopter in the Swedish armed forces with any armament except for self protection. The purpose of this thesis is to evaluate the Swedish anti-tank helicopter companies, based on William S. Lind’s theory of maneuver warfare. In conclusion, the tactics of the anti-tank helicopter companies correlate to a great deal with the theory of Lind, implicating that armed helicopters are very useful within maneuver warfare.

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