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41	Lean-verktyg i svenska tillverkande företag : -Några företags upplevda påverkan gällande driftsekonomin och miljöprestationer Alexander, Bång January 2020 (has links) Bakgrund & Problemdiskussion: Lean består av en mängd olika verktyg som är skapade för olika ändamål, i syfte att skapa sig konkurrensfördelar gentemot andra företag. Användandet av metoden kan innebära att det blir bättre kommunikation, större tillit eller förbättringar i driftsekonomin. På senare år har det även kommit ett förändrat krav på företagen gällande miljön, vilket gjort att de inte endast kan fokusera på hur de kan förbättra de operativa processerna. Företagen försöker därför kombinera de traditionella prestationsmålen (ex: kvalitet & effektivitet) med miljömål. Här har det visat sig att Lean:s tankesätt även kan användas för att förbättra miljöprestationerna och skaffa sig konkurrensfördelar genom det. Men det är långt ifrån alla företag som implementerat metoden som lyckats att få konkurrensfördelar. Vilket beror på att företagen har bristande kunskaper över vilken påverkan de olika lean-verktygen har. Syfte: Syftet med denna studien är att identifiera vilka lean-verktyg svenska tillverkande företag arbetar med samt hur företagen arbetar med dessa. Vidare avser studien att öka förståelse över vilken uppfattad påverkan företags arbete med lean-verktygen har på driftsekonomin och miljöprestationerna. Metod: Tillvägagångssättet utgår ifrån en komparativ flerfallsstudie med kvalitativ karaktär. Materialet är inhämtat från tre tillverkande företag. Intervjuerna är genomförda genom strukturerade frågor via mail, samt semi-strukturerade frågor via telefon. Den inhämtade datan är sedan analyserad för att finna likheter och skillnader mellan fallföretagen, men även gentemot tidigare forskningen. Slutsats: Utifrån denna studien visar det sig att företagen anpassar sitt användande av de olika lean-verktygen till sin verksamhet. Där användandet av lean-verktygen upplevs påverka att det blir ett större kundfokus i företagen. Arbetet med lean-verktygen upplevs även bidra till att det blivit bättre kvalitet på företagen produkter och processer, samt att flexibiliteten och pålitligheten kunnat förbättras. I denna studien visar det sig även att företag börjar tänka mer på hur deras processer och produkter påverkar miljön. Där arbetandet med lean-verktygen visat sig att företagens miljöprestationer kan förbättras. I denna studien visar det sig att användandet av lean-verktygen bidragit till att materialanvändningen kunnat reducerats. / Background and problem discussion: Lean consists of a variety of tools that have been created for different purposes, in order to create competitive advantages over other companies. The use of the method can mean that they become better communication, greater confidence or improvements in the operating economy. In recent years there has also been a changed demand for companies regarding the environment, which means that they can not focus only on how they can improve the unproductive processes. The companies are therefore trying to combine the traditional performance goals (eg: quality & efficiency) with environmental goals. Here it has been found that Lean's way of thinking can also be used to improve environmental performance and gain competitive advantages through it. But it is far from all companies that have implemented the method that managed to gain competitive advantage. This is because companies have a lack of knowledge about the impact of the various lean tools. Purpose: The purpose of this study is to identify which Lean tools Swedish manufacturing companies work with and how the companies work with them. Furthermore, the study aims to increase understanding of the perceived impact that companies' work with lean tools have on the operating economy and environmental performance. Method: The approach is based on a comparative multi-case study with qualitative character. Where the material is obtained from three manufacturing companies. The interviews were conducted through structured questions via mail, as well as semi-structured questions via telephone interviews. The collected data is then analyzed to find similarities and differences between the fall companies, but also against previous research. Conclusion: Based on this study, it appears that companies are adapting their use of the various lean tools to their business. Where the use of the lean tools is perceived to affect their becoming a greater customer focus in the companies. The work with the lean tools is also perceived to contribute to improving the quality of the companies products and processes, and that flexibility and reliability could be improved. In this study it also turns out that companies are starting to think more about how their processes and products affect the environment. Where working with the lean tools has shown that companies' environmental performance can be improved. In this study, it appears that the use of the lean tools has contributed to the reduction in material use. Lean Lean-tools Usage of lean-tools Perceived impact Operating Economy Flexibility Dependability Speed (Time in Processes) Quality Cost Environmental Impact Lean Lean-verktyg Användning av lean-verktyg Upplevd påverkan Driftsekonomi Flexibilitet Pålitlighet Hastighet (Tid i processerna) Kvalitet Kostnader Miljöpåverkan Business Administration Företagsekonomi
42	Load Control Aerodynamics in Offshore Wind Turbines / Aerodynamik av laststyrning i havsbaserade vindkraftverk Cantoni, Lorenzo January 2021 (has links) Due to the increase of rotor size in horizontal axis wind turbine (HAWT) during the past 25 years in order to achieve higher power output, all wind turbine components and blades in particular, have to withstand higher structural loads. This upscalingproblem could be solved by applying technologies capable of reducing aerodynamic loads the rotor has to withstand, either with passive or active control solutions. These control devices and techniques can reduce the fatigue load upon the blades up to 40% and therefore less maintenance is needed, resulting in an important money savings for the wind farm manager. This project consists in a study of load control techniques for offshore wind turbines from an aerodynamic and aeroelastic point ofview, with the aim to assess a cost effective, robust and reliable solution which could operate maintenance free in quite hostile environments. The first part of this study involves 2D and 3D aerodynamic and aeroelastic simulations to validate the computational model with experimental data and to analyze the interaction between the fluid and the structure. The second part of this study is an assessment of the unsteady aerodynamic loads produced by a wind gust over the blades and to verify how a trailing edge flap would influence the aerodynamic control parameters for the selected wind turbine blade. / På grund av ökningen av rotorstorleken hos horisontella vindturbiner (HAWT) under de senaste 25 åren, en design som har uppstod för att uppnå högre effekt, måste alla vindkraftkomponenter och blad stå emot högre strukturella belastningar. Detta uppskalningsproblem kan lösas genom att använda metoder som kan minska aerodynamiska belastningar som rotorn måste tåla, antingen med passiva eller aktiva styrlösningar. Dessa kontrollanordningar och tekniker kan minska utmattningsbelastningen på bladen med upp till 40 % och därför behövs mindre underhåll, vilket resulterar i viktiga besparingar för vindkraftsägaren. Detta projekt består av en studie av lastkontrolltekniker för havsbaserade vindkraftverk ur en aerodynamisk och aeroelastisk synvinkel, i syfte att bedöma en kostnadseffektiv, robust och pålitlig lösning som kan fungera underhållsfri i tuffa miljöer. Den första delen av denna studie involverar 2D- och 3D-aerodynamiska och aeroelastiska simuleringar för att validera beräkningsmodellen med experimentella data och för att analysera interaktionen mellan fluiden och strukturen. Den andra delen av denna studie är en bedömning av de ojämna aerodynamiska belastningarna som produceras av ett vindkast över bladen och för att verifiera hur en bakkantklaff skulle påverka de aerodynamiska styrparametrarna för det valda vindturbinbladet. Wind Turbine Offshore Blade Rotor Computational Fluid Dynamics Airfoil Aerodynamic Aeroelasticity Simulation Fluid Structure Interaction Loads Control Response Harmonics Vibration Damping Flutter Trailing Edge Flaps Wind Gust Lift Drag Unsteady Pressure Velocity Vindkraftverk offshore blad rotor beräkningsvätske-dynamik flygplatta aerodynamisk aeroelasticitet simulering vätska struktur interaktion belastningar kontroll respons övertoner vibrationer dämpning fladdring bakkant klaffar vindstöt lyft Drag ostadig tryck hastighet Energy Engineering Energiteknik
43	Analyzing and Reducing Compilation Times for C++ Programs Mivelli, Dennis January 2022 (has links) Software companies often choose to develop in C++ because of the high performance that the language offers. Facilitated by static compilation and powerful optimization options, runtime performance is paid for with compilation time. Although the trade-off is inevitable to some extent, building very large C++ programs from scratch can take up to several hours if extra care is not taken during development. This thesis analyzes compilation times for C++ programs and shows how they can be reduced with the help of design patterns, implementation hiding, and framework related fixes. The results presented prove that compilation times can be decreased significantly with no drawbacks to the maintainability of a program. An in-depth analysis of compilation times and dependencies has been conducted for two large software modules from a representative company. Both modules take over an hour of CPU time each to compile. The time consumption for different compiler activities, such as parsing, preprocessing, and runtime optimization tasks have been measured for the modules. The compilation times for unit tests and mocks which use the GoogleTest framework have been analyzed. A simple method that may reduce compilation times by up to 50% for programs that use GoogleTest is presented. A dependency metric has been created, based on the number of include statements found recursively throughout a program. The dependency metric was found to be connected to compilation time for the two analyzed modules. Other factors that can influence compilation times are also shown, such as runtime optimization options, and the use of templates. Experiments which show how a typical usage of templates can drastically increase compilation times are presented. In addition, a solution which allows templates to be used while avoiding code bloat across translation units is reviewed. The solution effectively rivals non-template code in terms of compilation time. The Pointer to Implementation (PImpl) and Dependency Injection design patterns have been used to refactor a small program. Both design patterns performed well, reducing the total compilation time and total compiler memory usage by 70%. A program that detects dependency cycles has been created, but no cycles were found in any of two modules from the representative company. C++ Compilation Build Dependencies File Dependencies File inclusions Time Speed Compilation time Build time Design patterns PImpl Bridge Dependency injection Pointer to implementation Mocking GoogleTest gMock large large-scale Reduce Reduce compilation times Reduce build times C++ Kompilering Byggtid Beroenden Filberoenden Filinkluderingar Tid Hastighet Kompileringstid Designmönster PImpl Bridge Dependency injection Pointer to implementation Mockning Mocking GoogleTest gMock Storskalig Minska kompileringstid Minska Computer Sciences Datavetenskap (datalogi)
44	Analysis of Accuracy for Engine and Gearbox Sensors Dogantimur, Erkan, Johnsson, Daniel January 2019 (has links) This thesis provides a standardized method to measure accuracy for engine and gearbox sensors. Accuracy is defined by ISO 5725, which states that trueness and precision need to be known to provide a metric for accuracy. However, obtaining and processing the data required for this is not straight forward. In this thesis, a method is presented that consists of two main parts: data acquisition and data analysis. The data acquisition part shows how to connect all of the equipment used and how to sample and store all the raw data from the sensors. The data analysis part shows how to process that raw data into statistical data, such as trueness, repeatability and reproducibility for the sensors. Once repeatability and reproducibility are known, the total precision can be determined. Accuracy can then be obtained by using information from trueness and precision. Besides, this thesis shows that measurement error can be separated into error caused by the sensors and error caused by the measurand. This is useful information, because it can be used to assess which type of error is the greatest, whether or not it can be compensated for, and if it is economically viable to compensate for such error. The results are then shown, where it is possible to gain information about the sensors’ performance from various graphs. Between Hall and inductive sensors, there were no superior winner, since they both have their strengths and weaknesses. The thesis ends by making recommendations on how to compensate for some of the errors, and how to improve upon the method to make it more automatic in the future. statistical analysis engine gearbox sensor sensors rotation rotational speed differential pressure performance characteristics trueness precision accuracy Hall inductive induction gauge pressure reference hysteresis bias noise linearity non-linearity DEWESoft DAQ wheel tooth teeth absolute rotary encoder matlab XOR Gray binary LabView sampling measurement measuring statistisk analys motor växellåda sensor sensorer rotation rotationell hastighet fart differentiell tryck prestanda karaktäristik trueness precision accuracy noggrannhet onoggrannhet Hall induktiv induktion tryckskillnad referens hysteres bias avstånd brus linjäritet linearitet olinear olinjär olinearitet olinjäritet DEWESoft DAQ sampling mätning hjul tand tänder absolut rotationsgivare givare matlab XOR Gray binär LabView Elektroteknik och elektronik
45	Dynamic Speed Adaptation for Curves using Machine Learning / Dynamisk hastighetsanpassning för kurvor med maskininlärning Narmack, Kirilll January 2018 (has links) The vehicles of tomorrow will be more sophisticated, intelligent and safe than the vehicles of today. The future is leaning towards fully autonomous vehicles. This degree project provides a data driven solution for a speed adaptation system that can be used to compute a vehicle speed for curves, suitable for the underlying driving style of the driver, road properties and weather conditions. A speed adaptation system for curves aims to compute a vehicle speed suitable for curves that can be used in Advanced Driver Assistance Systems (ADAS) or in Autonomous Driving (AD) applications. This degree project was carried out at Volvo Car Corporation. Literature in the field of speed adaptation systems and factors affecting the vehicle speed in curves was reviewed. Naturalistic driving data was both collected by driving and extracted from Volvo's data base and further processed. A novel speed adaptation system for curves was invented, implemented and evaluated. This speed adaptation system is able to compute a vehicle speed suitable for the underlying driving style of the driver, road properties and weather conditions. Two different artificial neural networks and two mathematical models were used to compute the desired vehicle speed in curves. These methods were compared and evaluated. / Morgondagens fordon kommer att vara mer sofistikerade, intelligenta och säkra än dagens fordon. Framtiden lutar mot fullständigt autonoma fordon. Detta examensarbete tillhandahåller en datadriven lösning för ett hastighetsanpassningssystem som kan beräkna ett fordons hastighet i kurvor som är lämpligt för förarens körstil, vägens egenskaper och rådande väder. Ett hastighetsanpassningssystem för kurvor har som mål att beräkna en fordonshastighet för kurvor som kan användas i Advanced Driver Assistance Systems (ADAS) eller Autonomous Driving (AD) applikationer. Detta examensarbete utfördes på Volvo Car Corporation. Litteratur kring hastighetsanpassningssystem samt faktorer som påverkar ett fordons hastighet i kurvor studerades. Naturalistisk bilkörningsdata samlades genom att köra bil samt extraherades från Volvos databas och bearbetades. Ett nytt hastighetsanpassningssystem uppfanns, implementerades samt utvärderades. Hastighetsanpassningssystemet visade sig vara kapabelt till att beräkna en lämplig fordonshastighet för förarens körstil under rådande väderförhållanden och vägens egenskaper. Två olika artificiella neuronnätverk samt två matematiska modeller användes för att beräkna fordonets hastighet. Dessa metoder jämfördes och utvärderades. Machine Learning Artificial Intelligence MachineLearning Machine-Learning AI ML MLP Neural Networks Multilayer-Perceptron RFB RBF-Network Vehicle Automation AutonomousVehicles Autonomous SelfDriving Self-Driving Self Driving Curve Speed Adaptation Adaption CSA ACC Adaptive Cruise Control Driving Style Driver Behavior Behaviour Sample Samples Distance Derivative Speed Velocity Curvature Road Inclination Lane Width Type Acceleration Longitudinal Lateral Data Training Test Validation Results Discussion Sustainability Ethics Ethical Sustainable Future Today Tomorrow Yesterday Robot Robotics System Systems Class Classes Bin Bins Tree One A Dynamic Using Time Delay Volvo Car Cars Corporation Zenuity School Computer Science Master Degree Project Thesis Paper Object GPS Map Length Research Advanced Машинное Обучение Искусственный Интеллект AI ML MLP RBF Автомобиль Машына Сеть Робот Водитель Заворот Дорога Сам Сама Едет Ехать Учить Учит Учится Автоматизация Адаптация Результат Один Одна Одно Вчера Сегодня Завтра Дерево Карта ГПС Информатика Компьютер Наука Научная Работа Школа Вольво Завод Транспорт Maskininlärning Artificiell Intelligens Inlärning Maskin AI ML MLP RBF Neural Neurala Nätverk Artificiella Automation Själv Självkörande Körande Bil Fordon Robot Robotik Körstil Stil Beteende Adaption Kurva Lutning Väg CSA ACC Farthållare Hastighet Fart Hållare Inclination Körfält Fält Spår Bredd Typ Acceleration Longitudinell Lateral Data Traingin Test Validation Resultat Diskussion Längd Hållbarhet Etik Etiskt Framtid Dåtid Idag Imorgon System Class Klass Classer Klasser Träd En Ett Fler Flera Dynamisk Använda Tid Fördröjning Tids Volvo Car Corporation Object Zenuity Skola Dator Vetenskap Forkning Avancerad Projekt Exjobb Examensarbete Betyg GPS Karta Computer Sciences Datavetenskap (datalogi)

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