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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.
11

Samarbeid uten fellesskap : Om individuelle planer i kommunalt psykisk helsearbeid

Hansen, Gunnar Vold January 2007 (has links)
This thesis is about the implementation of individual plans in the municipal mental health sector. Persons with need for long-term and coordinated services are entitled to have an individual plan. The objectives of an individual plan are to see that the service provides user participation, individual adaptation, comprehension and coordination. The purpose of this thesis is to see if an individual plan really contributes to reaching these objectives. It is possible to see individual plans as a tool based on the ideology of New Public Management (NPM). As such, their basis is rational-instrumental logic. Mental health is, however, a sector recognized for different knowledge bases, indefinite relations between cause and result, and users with vague and complex needs. The reason for choosing this field of investigation is to see what happens when a sector recognized for ambiguity meets products designed upon a rational-instrumental logic. The study shows that it is difficult to achieve user participation and individual adaptations. The reason for this is first of all insignificant resources in the municipal sector. The service providers are mostly positive to user participation and user involvement. This is, however, difficult to achieve as long as the users do not understand the reason for an individual plan and they lack concrete goals for their lives. The prospect of making a comprehensive and coordinated service is only to a small extent dependent on individual plans. Instead it seems as if factors like how the municipality is organized, professional boundaries and insight into rehabilitation ideology and cooperation, account for how comprehensive and coordinated the service becomes. The individual plan should be administered by a service provider with overall responsibility to follow up the work (a coordinator). My results show that this coordinator usually has a very important role in assisting the users in getting the service they need. Often the plan is followed by a team meeting where the different service providers together meet the user. For some of the users, these meetings are an arena where they can influence decisions about the service.
12

Abstract Measure

Bridges, Robert Miller January 1957 (has links)
This study of abstract measure covers classes of sets, measures and outer measures, extension of measures, and planer measure.
13

The Design of a Uniplanar Printed Triple Band-Rejected UWB Antenna using Particle Swarm Optimization and the Firefly Algorithm

Mohammed, Husham J., Abdullah, Abdulkareem S., Ali, R.S., Abd-Alhameed, Raed, Abdulraheem, Yasir I., Noras, James M. 31 August 2015 (has links)
Yes / A compact planar monopole antenna is proposed for ultra-wideband applications. The antenna has a microstrip line feed and band-rejected characteristics and consists of a ring patch and partial ground plane with a defective ground structure of rectangular shape. An annular strip is etched above the radiating element and two slots, one C-shaped and one arc-shaped, are embedded in the radiating patch. The proposed antenna has been optimized using bio-inspired algorithms, namely Particle Swarm Optimization and the Firefly Algorithm, based on a new software algorithm (Antenna Optimizer). Multi-objective optimization achieves rejection bands at 3.3 to 3.7 GHz for WiMAX, 5.15 to 5.825 GHz for the 802.11a WLAN system or HIPERLAN/2, and 7.25 to 7.745 GHz for C-band satellite communication systems. Validated results show wideband performance from 2.7 to 10.6 GHz with S11 ˂ -10 dB. The antenna has compact dimensions of 28 × 30 mm2. The radiation pattern is comparatively stable across the operating band with a relatively stable gain except in the notched bands. / This work was supported in part by the United Kingdom Engineering and Physical Science Research Council (EPSRC) under Grant EP/E022936A, TSB UK under grant application KTP008734 and the Iraqi Ministry of Higher Education and Scientific Research.
14

FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard / FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard

Marques Novo, Francisco José, Saraiva Rézio, Henrique Manuel January 2004 (has links)
<p>In the last decades, high speed cutting has become an attractive technology in the wood industry. The possibility of reducing global costs in addiction with an increase in productivity, were the main reasons for the enlargement of the use of this technology. </p><p>As usual, these advantages are accompanied by disadvantages that should be carefully analyzed. If on the one hand cutting forces are reduced with increasing cutting speeds, on the other hand, the centrifugal forces affecting the tool are higher. Exposed to such high loads, there is a considerable risk of tool failure that embeds hazards for both machine and workers. </p><p>To prevent the risk of accidents and to guarantee safety in use, security standards have been implemented in industrial fields, imposing specific experimental tests, with defined procedure modes. Accordingly with these standards, the results obtained through the tests should fall inside limited ranges. The experimental tests suggested on the European Standards are intended to simulate the real working conditions of a rotating cutting tool, where extreme centrifugal forces are imposed by the high values of speed. Although their main importance, these destructive tests aren’t always practicable. It happens, for instance, with tools produced in small batch sizes, or as an ascertainment for the fail-critical speed during the development stage, or even due to physical incompatibilities between the tool and the laboratory testmachines. </p><p>The high value of weight associated with the cutting tool prototype developed and patented by Verktygs Larsson AB was an impediment to run the laboratorial tests specified by the standards, forcing the company to find a new way to assure the safety requirements of their product. </p><p>The main goal of this project was the development of an alternative method based on finite element theory to perform a safety analysis to the prototype of a wood cutter. This tool is used as a component in high speed planers. </p><p>In addiction to this primary objective, some considerations were made about other available models, with increased dimensions or even with different parameters. If there was the need, design changes could be assumed in order to guarantee that the tool reached the requisites of the safety standards. Considering an optimization effort, material changes would also be considered, to aim in the direction of reducing the tool weight and the consequent centrifugal forces.</p>
15

FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard / FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard

Marques Novo, Francisco José, Saraiva Rézio, Henrique Manuel January 2004 (has links)
In the last decades, high speed cutting has become an attractive technology in the wood industry. The possibility of reducing global costs in addiction with an increase in productivity, were the main reasons for the enlargement of the use of this technology. As usual, these advantages are accompanied by disadvantages that should be carefully analyzed. If on the one hand cutting forces are reduced with increasing cutting speeds, on the other hand, the centrifugal forces affecting the tool are higher. Exposed to such high loads, there is a considerable risk of tool failure that embeds hazards for both machine and workers. To prevent the risk of accidents and to guarantee safety in use, security standards have been implemented in industrial fields, imposing specific experimental tests, with defined procedure modes. Accordingly with these standards, the results obtained through the tests should fall inside limited ranges. The experimental tests suggested on the European Standards are intended to simulate the real working conditions of a rotating cutting tool, where extreme centrifugal forces are imposed by the high values of speed. Although their main importance, these destructive tests aren’t always practicable. It happens, for instance, with tools produced in small batch sizes, or as an ascertainment for the fail-critical speed during the development stage, or even due to physical incompatibilities between the tool and the laboratory testmachines. The high value of weight associated with the cutting tool prototype developed and patented by Verktygs Larsson AB was an impediment to run the laboratorial tests specified by the standards, forcing the company to find a new way to assure the safety requirements of their product. The main goal of this project was the development of an alternative method based on finite element theory to perform a safety analysis to the prototype of a wood cutter. This tool is used as a component in high speed planers. In addiction to this primary objective, some considerations were made about other available models, with increased dimensions or even with different parameters. If there was the need, design changes could be assumed in order to guarantee that the tool reached the requisites of the safety standards. Considering an optimization effort, material changes would also be considered, to aim in the direction of reducing the tool weight and the consequent centrifugal forces.
16

A Study of Two Problems in Nonlinear Dynamics Using the Method of Multiple Scales

Reddy, Basireddy Sandeep January 2015 (has links) (PDF)
This thesis deals with the study of two problems in the area of nonlinear dynamics using the method of multiple scales. Accordingly, it consists of two parts. In the first part of the thesis, we explore the asymptotic stability of a planar two-degree- of-freedom robot with two rotary (R) joints following a desired trajectory under feedback control. Although such robots have been extensively studied and there exists stability and other results for position control, there are no analytical results for asymptotic stability when the end of the robot or its joints are made to follow a time dependent trajectory. The nonlinear dynamics of a 2R planar robot, under a proportional plus derivative (PD) and a model based computed torque control, is studied. The method of multiple scales is applied to the two nonlinear second-order ordinary deferential equations which describes the dynamics of the feedback controlled 2R robot. Amplitude modulation equations, as a set of four first order equations, are derived. At a fixed point, the Routh-Hurwitz criterion is used to obtain positive values of proportional and derivative gains at which the controller is asymptotically stable or indeterminate. For the model based control, a parameter representing model mismatch is incorporated and again controller gains are obtained, for a chosen mismatch parameter value, where the controller results in asymptotic stability or is indeterminate. From numerical simulations with gain values in the indeterminate region, it is shown that for some values and ranges of the gains, the non- linear dynamical equations are chaotic and hence the 2R robot cannot follow the desired trajectory and be asymptotically stable. The second part of the thesis deals with the study of the nonlinear dynamics of a rotating flexible link, modeled as a one dimensional beam, undergoing large deformation and with geometric nonlinearities. The partial deferential equation of motion is discretized using a finite element approach to yield four nonlinear, non-autonomous and coupled ordinary deferential equations. The equations are non-dimensional zed using two characteristic velocities – the speed of sound in the material and a speed associated with the trans- verse bending vibration of the beam. The method of multiple scales is used to perform a detailed study of the system. A set of four autonomous equations of the first-order are derived considering primary resonance of the external excitation with one of the natural frequencies of the model and one-to-one internal resonance between two different natural frequencies of the model. Numerical simulations show that for certain ranges of values of these characteristic velocities, the slow flow equations can exhibit chaotic motions. The numerical simulations and the results are related to a rotating wind turbine blade and the approach can be used for the study of the nonlinear dynamics of a single link flexible manipulator. The second part of the thesis also deals with the synchronization of chaos in the equations of motion of the flexible beam. A nonlinear control scheme via active nonlinear control and Lyapunov stability theory is proposed to synchronize the chaotic system. The proposed controller ensures that the error between the controlled and the original system asymptotically go to zero. A numerical example using parameters of a rotating power generating wind turbine blade is used to illustrate the theoretical approach.
17

Inaktuella detaljplaners påverkan på utveckling och hållbarhetsfrågor : En fallstudie i Sollefteå kommun

Settlin, Settlin January 2022 (has links)
Sollefteå kommun är en landsbygdskommun som stått relativt still i exploateringen under många år men som nu blivit aktuell för en rad olika större etableringar. Detta har inneburit att många äldre detaljplaner finns kvar, och kan komma att bromsa utvecklingen. Kommunen har som mål att växa befolkningsmässigt med hållbarhet som utgångspunkt och därför bör det finnas en bra struktur för hur hinder som inaktuella detaljplaner medför kan undvikas. Syftet med denna studie är att förstå vilka problem en inaktuell detaljplan kan leda till, om de förhindrar utveckling samt om hållbarhetsarbetet kan påverkas. Vilka konsekvenser får eventuellt upphävande och ersättning av planerna? Detaljplaner i Sollefteå kommun har studerats och intervjuer med berörda resurser gjorts för att få en bild av hur det ser ut idag och i vilken omfattning problemen uppstår. Den äldsta gällande planen är nära 100 år gammal och därmed framtagen för ett helt annat typ av samhälle. Det visar sig att en del hållbarhetsaspekter alltid funnits med i detaljplaner men idag ställs högre krav i dem och kunskapsläget är bättre. Det medför att en nyare och aktuell detaljplan kan främja arbetet mot att nå vissa miljömål. En svårighet är att en plan får definitionen som inaktuell först när hindren uppstår och de är på så sätt svåra att förebygga. Något som kan konstateras är att en inaktuell detaljplan kan hålla tillbaka utvecklingen samt göra åtgärder både dyrare och mer tidskrävande än nödvändigt. / relatively still in the development for many years, but which has now become relevant for several different major establishments. This has meant that many older detailed plans remain and may slow down development. The municipality's goal is to grow in terms of population with sustainability as a guideline. Therefore, there should be a good structure for how obstacles caused by outdated detailed plans can be avoided. The purpose of this study is to understand what problems an outdated detailed plan can lead to, whether they prevent development and whether sustainability work can be affected. What are the consequences of any revocation and compensation of the plans? Detailed plans in Sollefteå municipality have been studied and interviews with relevant resources have been done to get a good view of ​​what it looks like today and to what extent the problems arise. The oldest current plan is almost 100 years old and developed for a completely different type of society. It turns out that some sustainability aspects have always been included in detailed plans, but today higher demands are placed on them, and the state of knowledge is better. This means that a newer and current detailed plan can promote the work towards achieving certain environmental goals. One difficulty is that a plan is defined as outdated just when obstacles arise, and the problems are therefore difficult to prevent. Something that can be stated is that not updated detailed plans can hold back development and make measures both more expensive and more time-consuming than necessary. / <p>2022-06-21</p>
18

Brandskydd under byggtid med BIM : Förbättringsmöjligheter för brandskyddet under byggtid i skedesstyrda APD-planer med BIM

Lundblad Roth, Rebecka, Jerräng Carlstedt, Ludwig January 2018 (has links)
Vid en brand på byggarbetsplatsen finns det risk för personskador, skador på egendom och att byggproduktionen hamnar i ett driftstopp som kan bli kostsamt. Det finns brister vid planeringen av brandskyddet under byggtid (BUB) och vid olika arbetsmoment på byggarbetsplatsen. Planeringen av BUB behöver förbättras utefter hur en byggarbetsplats, och således brandrisker, förändras under byggproduktionen. Ett förslag på hur detta skulle kunna förbättras är att BUB är med i produktionsplaneringen och redovisas på arbetsplatsdispositionsplaner (APD-planer). Arbetsmoment som kan vara en brandrisk borde också planeras tillsammans med BUB för en brandsäkrare byggarbetsplats. Brandskyddsprojektering är idag till stor del inte inkluderat i det digitala arbetssättet som Building Information Modeling (BIM) innebär. Att brandkonsulten inte är med och arbetar i BIM leder till att de fördelar som finns med samverkan mellan olika discipliner inte kan utnyttjas. Den forskning som finns rörande brandskydd i BIM idag fokuserar på projektering av den färdiga byggnaden och hur brandskydd ska kunna inkluderas i BIM. Det finns idag ingen forskning som berör både brandskydd på byggarbetsplatsen och BIM-projektering av byggarbetsplatsen. Detta leder till ett kunskapsglapp mellan BIM som arbetssätt på byggarbetsplatsen och planering av BUB. På grund av de påträffade problemområdena syftade studien till att undersöka förbättringsmöjligheter för brandskyddet under byggtid. Detta genom att kartlägga förutsättningar och tillämpbara områden där BUB kan inkluderas i arbetet med APD-planer och tidsberoende BIM-modeller. Målet med studien var att framta ett underlag till framtida arbetsmetoder där BUB, APD-planer och BIM på byggarbetsplatser används tillsammans. För att uppfylla syftet utfördes en litteraturstudie och en intervjustudie. Litteraturstudien gjordes för att granska publicerat material rörande BUB, byggarbetsplatsplanering med APD-planer samt BIM på byggarbetsplatsen och BIM med hänsyn till brandskydd. Intervjustudien gjordes för att få en inblick i hur personer använder sig av BUB, APD-planer och BIM på byggarbetsplatser (i praktiken). Den information som framkom från teoretisk kunskap och praktiska erfarenheter analyserades för att kartlägga förutsättningar och tillämpbara områden där BUB kan inkluderas i arbetet med APD-planer och tidsberoende BIM-modeller. Detta för att kunna överbrygga gapet som finns mellan BUB, APD-planer och användandet av BIM på byggarbetsplatser. De identifierade områden som framtagits är planering, kommunikation samt kontroll och uppföljning. För att kunna arbeta med BUB och skedesstyrda APD-planer i BIM inom de identifierade områdena finns det krav på vissa grundläggande förutsättningar. För att kunna ta fram APD-planer och göra dessa skedesstyrda i BIM-modellen krävs det utbildning för att få nödvändig kunskap och kompetens hos både projekteringen och produktionen. Det kommer också krävas ett tidigt samarbete mellan produktionen och projekteringen för att täcka alla kompetensområden som behövs vid planering av produktionen av en byggnad med BIM. För att kunna projektera APD-planer i BIM är det även en förutsättning att alla discipliner arbetar i BIM-modellen. Saknas det information, exempelvis landskap, går det inte att göra fullständiga APD-planer över byggområdet i BIM. Att ta fram skedesstyrda APD-planer där BUB inkluderas i en BIM-modell har i denna studie visat sig vara fördelaktigt inom flera områden. Att planera BUB tillsammans med APD-planer ivgör att brandskyddet på byggarbetsplatsen kan planeras med hänsyn till produktionen och att kraven går att genomföra utan att produktionen blir lidande. Med skedesstyrda APD-planer i en BIM-modell blir det möjligt att visualisera förändringarna på byggarbetsplatsen och på så vis även förutspå vilka brandrisker som uppkommer under olika skeden i byggnationen. BUB inkluderat i en BIM-modell kan vara ett verktyg för att förbättra kommunikationen på byggarbetsplatsen. Detta genom att informationen som läggs in blir mer projektspecifik vilket leder till att BUB blir lättare att förmedla, tydligare att följa och mer förståelig. Med bättre information och ökad kunskap om BUB kan kontroll och uppföljning utföras effektivare och därmed förbättra brandskyddet genom att kontrollerna utförs med en högre kvalité. Detta ger förhoppningen om att brandskydd under byggtid blir en större del av planering och projektering av byggarbetsplatsen samt leder till en säkrare byggarbetsplats. / In case of a fire at a construction site there is a risk of personal injury, property damage and stop in the building production that may be costly. There are shortcomings in the planning of fire safety at the construction site and at different construction methods. The planning of fire safety at construction sites are also in need of improvements according to how a construction site, and thus risks of fire, change during construction production. This by planning the fire safety along with the production of the building and that the fire safety is presented on workplace disposition plans. Fire protection design is mostly not included in the digital work method that Building Information Modeling (BIM) implies. The fact that the fire consultant is not involved with and works in BIM means that the benefits of collaboration between different disciplines cannot be utilized. The research on fire protection in BIM today focuses on the design of the completed building and how fire protection can be included in BIM. There is currently no research regarding both fire safety at the construction site and BIM modelling of the construction site. This leads to a gap between BIM as a working method at the construction site and the planning of fire safety. Because of mentioned problem areas, the study’s purpose was to investigate improvements for fire safety on construction sites. This by mapping out conditions and applicable areas where fire safety can be included in the planning of workplace disposition plans in time-dependent BIM models. The aim of the study was to provide a basis for future work methods in which fire safety, workplace disposition plans and BIM at construction sites are used together. To fulfill the purpose, a literature study and an interview study were conducted. The literature study was conducted to review published material regarding fire safety, construction site planning with workplace disposition plans, BIM at the construction site and BIM with fire safety design. Interviews were conducted to gain an insight into how people use fire safety documents, workplace disposition plans and BIM on construction sites (in practice). The information derived from theoretical knowledge and practical experience was analyzed to map the conditions and applicable areas where fire safety can be included in the planning of workplace disposition plans and time-dependent BIM models. This to bridge the gap between fire safety, workplace disposition plans and the use of BIM on construction sites. The identified areas that have been established are planning, communication and control and follow-up. To be able to work with fire safety and workplace disposition plans in time-dependent BIM model within the identified areas, there are some basic conditions that needs to be fulfilled. To be able to develop workplace disposition plans and make these time-dependent in the BIM model, education is needed to get the necessary knowledge and skills in both the design and production. There also needs to be an early collaboration between production and design to cover all areas of expertise needed in planning the production of a building with BIM. To be able to design workplace disposition plans in BIM, it is also a prerequisite that all disciplines work in the BIM model. If there is no information, such as information of the landscape, it is not possible to complete workplace disposition plans over the whole construction site in BIM. To develop time-dependent workplace disposition plans where fire safety are included in a BIM model, this study has proven to be beneficial in several areas. Planning the fire safety together with workplace disposition plans allows the fire protection at the construction site to be planned viregarding production and that the fire safety requirements can be implemented without the production being compromised. Time-dependent workplace disposition plans in a BIM model make it possible to visualize the changes at the construction site, thus predicting fire risks during different stages of the construction. Fire safety included in a BIM model can be a tool for improving communication at the construction site. This is because the information about the fire safety on construction sites inserted becomes more project-specific, which means that the information about the fire safety requirements can be easier to convey, clearer to follow and more understandable. With better information and increased knowledge about fire safety on construction sites, control and follow-up can be performed more effectively and therefore improving the fire safety by performing the controls with a higher quality. This gives the hope that fire protection during construction will be a major part of planning and designing the construction site and that this will lead to a safer construction site.
19

Fabrication and Characterization of Planar-Structure Perovskite Solar Cells

Liu, Guoduan 01 January 2019 (has links)
Currently organic-inorganic hybrid perovskite solar cells (PSCs) is one kind of promising photovoltaic technology due to low production cost, easy fabrication method and high power conversion efficiency. Charge transport layers are found to be critical for device performance and stability. A traditional electron transport layer (ETL), such as TiO2 (Titanium dioxide), is not very efficient for charge extraction at the interface. Compared with TiO2, SnO2 (Tin (IV) Oxide) possesses several advantages such as higher mobility and better energy level alignment. In addition, PSCs with planar structure can be processed at lower temperature compared to PSCs with other structures. In this thesis, planar-structure perovskite solar cells with SnO2 as the electron transport layer are fabricated. The one-step spin-coating method is employed for the fabrication. Several issues are studied such as annealing the samples in ambient air or glovebox, different concentration of solution used for the samples, the impact of using filter for solutions on samples. Finally, a reproducible fabrication procedure for planer-structure perovskite solar cells with an average power conversion efficiency of 16.8%, and a maximum power conversion efficiency of 18.1% is provided.
20

Ung och arbetslös : -En studie om unga arbetslösas bakgrund, nuvarande situation och framtidsvision. / Young and unemployed : -A study of young unemployed people’s background, current situation and future vision.

Homsi, Ramona, Mecavica, Amra January 2014 (has links)
The purpose of this study is to increase understanding of the unemployed youth. To achievethat, we have investigated who the unemployed young people are, how their wellbeing isaffected and what they need for a change to take place. The study was conducted in amedium-sized Swedish city with the help of a method combination. The target population forthis study is people enrolled in “Job-guarantee for Youth” in spring 2014. The quantitativepart of the study was conducted using questionnaires and qualitatively through interviewswith seven young people in the group. The result shows that the social heritage is reflected inwhich education the young people have chosen and what future plans they have. Furthermore,the study shows that mental health is affected. The economy as well. / Syftet med den här studien är att öka förståelsen för arbetslösa ungdomar. För att uppnå detsyftet har vi undersökt vilka de arbetslösa är, hur de mår och vad de behöver för att enförändring ska kunna ske. Studien genomfördes i en medelstor svensk stad med hjälp av enmetodkombination. Målgruppen för vår studie är personer inskrivna i ”jobbgaranti förungdomar” under våren 2014. Den kvantitativa delen i studien genomfördes med hjälp avenkäter och den kvalitativa med hjälp av intervjuer med sju berörda personer i gruppen.Resultatet visar att det sociala arvet avspeglar sig i vilken utbildning de unga har valt ochvilka framtidsplaner dem har. Dessutom visar studien att den psykiska hälsan påverkasnegativt. Ekonomin likaså.

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