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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.
231

Spirometri med en smarttelefon : Utveckling av en app för att mäta rotationshastigheten till en spirometerprototyp för smarttelefoner / Spirometry with a smartphone : Development of an application for calculating the rotation velocity of a spirometry prototype for smartphones

Andersson, Andreas January 2017 (has links)
Målet med detta examensarbete har varit att utveckla en app med en algoritm för att mäta rotationshastigheten hos en prototyp för en spirometerlösning till en låg kostnad för smart- telefoner. En förstudie har gjorts av smarttelefoners användbarhet för att mäta hälsotillstånd och vilka alternativa lösningar och algoritmer som finns för att mäta rörelsedetektion. I detta arbete har en app med en algoritm utvecklats för att detektera rörelser och mäta rotations- hastigheten hos spirometerprototypens turbin filmad med en smarttelefonkamera. För att metoden ska fungera är det viktigt att rotationshastigheten understiger hälften av kamerans fps (bilder per sekund). Rotationshastigheten hos turbinen måste därför begränsas och det behövs en kamera som klarar minst 120 fps för att fånga rörelserna i prototypens turbin.Arbetet har resulterat i en fungerande algoritm för att bestämma turbinens rotationshastighet. Den utvecklade algoritmen detekterar topparna i en PPG (photoplethysmogram). För att minska beräkningstiden och för att öka noggrannheten analyserar algoritmen färgintensiteten i ett begränsat område, ett s.k. ROI (Region of Interest) i varje bild. Det finns stora möjligheter att använda denna algoritm för att fortsätta utvecklingen av detta alternativa sätt att utföra spirometritester. / The goal with this bachelor thesis was to develop an application with an algorithm to measure the rotation speed of a prototype, as a low-cost solution for measuring spirometry with a smartphone. In a pilot study it was investigated how a smartphone can be used to measure health and what algorithms there are to detect motion in videos. After the pilot study an app with the function to record a video by using the camera of a smartphone and then use an algorithm to detect the rotation speed in the spirometry-prototype’s turbine was developed. To make it work it is important that the rotation speed is low enough so it does not exceed half of the cameras fps. Therefore, to capture the rotation speed of the spirometry-prototype’s turbine the rotation needs to be limited and a smartphone with a camera with at least 120 fps is required.The result of this work is an algorithm that can measure the rotation speed in the spirometry prototype turbine. The algorithm is detecting the peaks in a PPG. To minimize the computation time and to increase the accuracy the algorithm analyses the colour intensity over a ROI in every frame. There is great potential to use this algorithm to further develop this alternative method of measuring spirometry.
232

Design and Tests of a Biofeedback Based Weight Bearing Rehabilitation Device / Design och test av en biofeedback-baserad viktbärande rehabiliteringsenhet

Setiawan, Stanley January 2019 (has links)
As upper-limb rehabilitation devices development continue to grow, lower limb rehabilitation devices have limited development. Thus a device that measures weight bearing of heel and forefoot during gait and also produces auditory feedback at certain thresholds were made in this project. The device was constructed based on an ARM-Core microcontroller and was supported by 5 force sensing resistor sensors for each foot. Communications between the modules and the computer as the GUI were established using an UART interface. For testing, sensors were placed beneath the foot using a stretchable cloth so each different subjects’ pressure points were correctly placed. The biofeedback used for this device was by enabling a buzzer and LED embedded to the designed board that turns on when heel strike or push off reached acertain threshold. Testing were divided into phase one and two. From phase one, it was concluded that both push off and heel strike event can have a reading exceeding 8.5% of the body weight. It was then used as a threshold for the biofeedback event. During the biofeedback tests, improvements in the subjects’ walking pattern and reading were noted. Results suggest that biofeedback can change the behavior of the subject. / I takt med att utvecklingen av rehabilitationsapparater i övre extremiteterna fortsätter att växa, har rehabiliteringsanordningar för nedre extremiteterna begränsad utveckling. Således gjordes en anordning som mäter viktbearbetning av häl och framfot under gång och också ger hörselåterkoppling vid vissa trösklar i detta projekt. Enheten var konstruerad baserad på en ARM-Core mikrokontroller och stöds av 5 kraftsavkännande motståndssensorer för varje fot. Kommunikation mellan modulerna och datorn som GUI upprättades medhjälp av ett UART-gränssnitt. För testning placerades sensorer under foten meden töjbar duk så att varje olika försöks tryckpunkter placerades korrekt. Den biofeedback som användes för den här enheten var genom att aktivera en summer och LED inbäddad i det konstruerade kortet som slås på när hälslaget eller skjutstoppet nådde en viss tröskel. Testningen delades in i fas en och två. Frånfas ett drogs slutsatsen att både push off och hälstreffhändelse kan ha en avläsningsom överstiger 8.5% av kroppsvikt. Den användes sedan som en tröskelför biofeedback-händelsen. Under biofeedback-testen noterades förbättringar i försökspersonernas gångmönster och läsning. Resultaten tyder på att biofeedback kan förändra beteendet hos ämnet.
233

Framtagning av extern borstmodul för robotar avsedda för undervattensrengöring / Production of external brush module for robots intended for underwater cleaning

Stenberg, Nina, Pachacama Guallichico, Oscar January 2019 (has links)
Weda AB är ett svenskt miljöteknikföretag som utvecklar produkter avsedda för undervattensrengöring. B600 är en av Wedas undervattensrengöringsrobotar som används inom den offentliga sektorn. B600 består av en kraftfull pump och kombineras med två roterande valsborstar både bak och fram. Valsborstarna är avsedda för att bara föra in smuts i pumpen under städning, vilket gör att B600 saknar idag skrubbeffekt för effektivare städning. Detta examensarbete är en fortsättning på de tidigare projekten genomförda åt Weda AB utförda på Kungliga Tekniska Högskolan (KTH). Målet är att ta fram ett lösningsförslag samt en fungerande prototyp av en extern borstmodul, samt eventuellt vidareutveckla åtgärder mot de brister som dök upp i de tidigare projekten och effektivisera städning på B600. Projektet består av fyra faser vilka är problemdefinition, förundersökning, konceptutveckling och utvärdering. Problemdefinitionsfasen innehar problembeskrivning, målformulering och avgränsningar. För att komma fram till ett lösningsförslag utifrån kundkrav och kundbehov identifieras produktspecifikationer. Genom att använda Quality Function Deployment (QFD) upprättades produktspecifikationer som var väsentliga för att kunna tillfredsställa kundkraven och för att veta vilka utgångspunkter detta projekt ska inrikta sig mot. Förundersökningsfas beskriver kortfattat om de tidigare projekten utförda på KTH samt presenterar olika material och olika tillverkningsprocesser inför produktion. Konceptutvecklingsfas omfattar CAD-modellering av lösningsförslag, prototypframtagning samt prototyptestning som säkerställer om lösningsförslaget kommer att fungera i verkligheten. Sista fasen utvärdering analyserar resultaten utifrån prototyptestning. / Weda AB is a Swedish environmental technology company that develops products intended for under-water cleaning. The B600 is one of Wedas underwater cleaning robots used in the public sector. B600 consist of a powerful pump and is combined with two rotating roller brushes, one on the front and the other one on the back. The roller brushes are intended to insert only dirt into the pump during the cleaning, which means that the B600 does not have today a scrubbing effect for more efficient cleaning. This thesis is a continuation of previous projects carried out at Weda AB and performed at the Royal Institute of Technology (KTH). The goal is to develop a proposal solution and a functional prototype of an external brush module that will further develop previous insufficiencies and streamline cleaning on the B600. The project consists of four phases which are planning, preliminary research, concept development and evaluation. The planning phase covers up problem description, goal definitions and delimitations set to minimize the scope of the project. To arrive at a proposal solution based on customer requirements and customer needs, identifies product specifications. By using Quality Function Deployment (QFD), product specifications were established which were essential to satisfy the customer requirements and to know which points of departure this project should focus on. Preliminary investigation describes briefly about previous projects performed at the KTH and presents various materials and different manufacturing processes that can be used at the production. Concept development phase includes CAD-modeling of the proposal solution, prototype development and prototype testing that ensures whether the proposal solution will work in reality. The final phase evaluation analyzes the results based on prototype tests.
234

Design and Development of a Canine behaviour analysis device / Utveckling och konstruktion av en beteendeanalysanordning för hundar

Jacob, Allan, Papadopoulos, Jannis January 2017 (has links)
Denna uppsats är ett projekt där målet var att utveckla en beta-prototyp för en beteendeanalysanordning för hundar. Enheten använder rörelsespårningssensorer för att analysera och förutsäga dess beteende. Examensarbetet började med att analysera kundsegmentet och definiera designriktningen baserat på den grunden. Detta följdes sedan av konceptutveckling, realisering och utvärdering. Detta inkluderade traditionella designmetoder och designförfaranden där designerna utvärderades och modellerades. Detta var en mycket iterativ designprocess som följdes av Moldflow-analyser. Prototyper gjordes vid KTH: s Prototypcenter, där olika versioner tillverkades i FDM-skrivare och validerades. Beta-prototypen producerades senare med SLA-skrivare och validerades med avseende på vattentäthet. Dropptest simulerades med ANSYS för att bestämma deformationen av enheten när de släpps och resultaten pekar på att enheten med god marginal befinner sig inom acceptabelt deformationsintervall. Moldflowanalyserna belyste aspekter av designen som krävde ytterligare modifieringar för att förbättra produktens tillverkningsbarhet. / This thesis is a project where the aim was to develop a beta prototype for a behaviour analysis device for dogs. The device uses motion tracking sensors to analyse and predict its behaviour. The thesis project started with understanding the customer segment and defining the design direction on that basis. This was then followed by concept generation, realisation and evaluation. This included traditional design methodologies and design procedures where the designs were evaluated and modelled. This was a highly iterative design process which was followed by FEA and Moldflow analyses. Prototypes were made at the KTH prototyping centre, where various versions were made in FDM printers and validated. The beta prototype was later produced using SLA printers and validated for waterproofing. Drop test was simulated with Ansys to determine the amount of deformation in the device when dropped, the results point out that the device is well within an acceptable deformation range. The Moldflow analyses highlighted aspects of the design that required further modifications to improve the manufacturability of the device.
235

Critical Success Factors For Evolutionary Acquisition Implementation

Bjorn, Brig J 01 January 2012 (has links)
Due to extensive challenges to the efficient development and fielding of operationally effective and affordable weapon systems, the U.S. employs a complex management framework to govern defense acquisition programs. The Department of Defense and Congress recently modified this process to improve the levels of knowledge available at key decision points in order to reduce lifecycle cost, schedule, and technical risk to programs. This exploratory research study employed multiple methods to examine the impact of systems engineering reviews, competitive prototyping, and the application of a Modular Open Systems Approach on knowledge and risk prior to funding system implementation and production. In-depth case studies of two recent Major Defense Acquisition Programs were conducted to verify the existence and relationships of the proposed constructs and identify potential barriers to program success introduced by the new process. The case studies included program documentation analysis as well as interviews with contractor personnel holding multiple roles on the program. A questionnaire-based survey of contractor personnel from a larger set of programs was executed to test the case study findings against a larger data set. The study results indicate that while some changes adversely affected program risk levels, the recent modifications to the acquisition process generally had a positive impact on levels of critical knowledge at the key Milestone B decision point. Based on the results of this study it is recommended that the Government improve its ability to communicate with contractors during competitive phases, particularly with regard to requirements management, and establish verifiable criteria for compliance with the iii Modular Open Systems Approach. Additionally, the Government should clarify the intent of competitive prototyping and develop a strategy to better manage the inevitable gaps between program phases. Contractors are recommended to present more requirements trade-offs and focus less on prototype development during the Technology Development phases of programs. The results of this study may be used by policy makers to shape future acquisition reforms; by Government personnel to improve the implementation of the current regulations; and by contractors to shape strategies and processes for more effective system development. This research may be used by the Government to improve the execution of acquisition programs under this new paradigm. The defense industrial base can use this research to better understand the impacts of the new process and improve strategic planning processes. The research methodology may be applied to new and different types of programs to assess improvement in the execution process over time.
236

A context-aware application mobility approach

Johansson, Dan January 2012 (has links)
Over the last two decades, mobile computing has gone from being a mere vision to becoming a reality, ubiquitously present in our everyday lives. There are different types of mobility, from user and terminal mobility, to mobility of services and sessions. This thesis is mainly about application mobility { the ability for an application to migrate between different host devices during its execution. The aim of this thesis work is to explore and advance the area of application mobility. The thesis approaches this goal through focusing on three research issues: Architectural considerations for application mobility; Context-awareness support and application adaptability; and Concept exploration.The contributions of this thesis include the identification of requirements for application mobility and a proposal for a decentralized, global scale architecture for application mobility, building on the peer-to-peer paradigm. Several prototypes of systems allowing application mobility are deployed, manifesting concepts such as decentralized system layout, context-awareness, context quality and global scope. Evaluations are both quantitative and qualitative. Other contributions of this thesis are the design and evaluation of a framework building on cloud and peer-to-peer technology to enable mobile sessions and an exploration of the concept of application mobility. / Sense Smart City, MOSA - mobil och öppen tjänste-access, NIMO - Nordic Interaction and Mobility Research Platform
237

Exploring electromagnetic induction as a power source for interactive human-powered devices

Gonzalez Rabal, Elena January 2020 (has links)
In the last decade, we have seen an increasing interest in the designing of interactive technology that is limited in energy usage to our bodily capabilities. This field is commonly referred to as Human-Power Interaction (HPI). The aim of HPI is to create battery-free devices that are powered solely from human interactions. Therefore, it is important that power generation and interactivity are aligned and not separated tasks. In this paper, a novel way of providing human power to interactive devices has been investigated using electromagnetic induction. The focus has been to explore and play with the fundamental principles of electromagnetic induction with the intention of evaluating its potential as a new type of interactive power generation. With the help of a physical prototype and an application to demonstrate its capabilities, the results show that electromagnetic induction could potentially be considered as a relatively easy way to build human-powered sources for interactive devices using this principle. / Under det senaste decenniet har vi sett ett ökande intresse för utformningen av interaktiv teknik som är begränsad i energianvändningen till det av våra kroppsliga förmågor. Detta fält kallas vanligen Human-Power Interaction (HPI). Målet med HPI är att skapa batterifria enheter som drivs enbart från mänskliga interaktioner. Därför är det viktigt att kraftproduktion och interaktivitet är anpassade till varandra och inte separerade aktiviteter. I denna rapport har ett nytt sätt att tillhandahålla mänsklig kraft till interaktiva enheter undersökts med hjälp av elektromagnetisk induktion. Fokus har varit att utforska och leka med de grundläggande principerna för elektromagnetisk induktion i avsikt att utvärdera dess potential som en ny typ av interaktiv kraftproduktion. Med hjälp av en fysisk prototyp och en tillämpning för att demonstrera dess förmåga, visar resultaten att elektromagnetisk induktion potentiellt kan ses som ett relativt enkelt sätt att bygga människodrivna källor för interaktiva enheter med denna princip.
238

The influence of lateral foot displacement on cycling efficiency and maximal cycling power

Harper, Sara Anne 13 May 2014 (has links)
No description available.
239

Developing a Model System to Probe Biological Mechanisms of Post-Translational Modifications that Destabilize the Nucleosome

Beasley, Miranda L. January 2014 (has links)
No description available.
240

IDENTICAL CONSTITUENT COMPOUNDING: A CONCEPTUAL INTEGRATION-BASED MODEL

Benjamin, Brandon Lee 31 May 2018 (has links)
No description available.

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