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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.
281

Beräkningsmodell som avser transport av massor - Jämförelse kostnader och utsläppspåverkan orsakad av lastbilstransporter av schaktmassor till och från ett entreprenadprojekt / Calculation model concerning the transportation of excavation masses

Carlsson, Carl-Oscar, Forslund, Johan January 2020 (has links)
Skanska har identifierat ett problem med att Örebro kommun har hårda restriktioner kring deponier och mängden massor som får lossas där. Då byggtakten under lång tid varit hög i Örebro ser Skanska att många deponier kring Örebro börjar bli fulla. I de fall då närmsta deponi inte har möjlighet att ta emot schaktmassor, orsakar det längre transportsträckor av schaktmassorna till andra deponier. Syftet med denna studie är därför att skapa en beräkningsmodell som jämför olika transportalternativs inverkan på miljön och ekonomin.Beräkningsmodellen i denna rapport har framställts genom litteraturstudier samt intervjuer. En tillämpning av beräkningsmodellen appliceras på två exempel för att illustrera utsläpp och kostnader.Beräkningsmodellen avgränsas till att beräkna utsläpp och kostnader som genereras från transporter av schaktmassor mellan projekt, deponi och täkt.Med hjälp av den framtagna beräkningsmodellen har kostnader och utsläpp illustreras för projektet Marieberg Törsjö 3:14. Två exempel beräknas vilka båda utgår från Marieberg Törsjö 3:14. Antagna föroreningar i marken medför att klassningen av massorna skiljer sig i de två exemplen. Detta medför att regler kring omhändertagning av massorna, arbetssätt och de olika geografiska platserna för deponier och täkter skiljer sig mellan de olika exemplen.I rapporten har en fungerande beräkningsmodell utvecklats, den illustrerar utsläpp och kostnader kopplade till transporten av massorna. Beräkningsmodellen kan användas av företag för att illustrera miljöpåverkan som transporter mellan två olika deponier eller täkter ger upphov till, samt prisskillnaden som de olika alternativen genererar. / Skanska has identified a problem that Örebro municipality having severe restrictions on landfills and what masses may be unloaded there. Since the construction rate has been high in Örebro for a long time, Skanska sees that many landfills around Örebro are getting full. In some cases when the nearest landfill is no longer able to receive excavation masses, the company is forced to transport the excavation masses unnecessary distances to other landfills. The purpose of this study is therefore to create a calculation model that compares the impact of different transport alternatives on both the environment and the economy.The calculation model is developed through literature studies and interviews. The calculation tool will be applied to two examples to illustrate emissions and costs.The calculation model is limited to calculating emissions and costs generated from transport of excavation masses between projects, landfills and quarries.Using the theoretical model developed, costs and emissions have been illustrated for the project Marieberg Törsjö 3:14. The two examples based on Marieberg Törsjö 3:14 differ in the classification of the masses. This means that rules regarding the handling of the masses, working methods and the different geographical locations for landfills and quarries differ between the different examples.A conclusion from this study is a working calculation model has been developed that illustrates emissions and costs associated with the transport of the masses. The calculation model can be used by companies to illustrate the environmental impact that transport between two different landfills or quarries generates, as well as the price difference generated by the different alternatives.
282

Analýza vybraného podnikatelského subjektu pomocí vybraných metod / Analysis of the Selected Company by Using the Selective Methods

Vaníčková, Veronika January 2017 (has links)
This master´s thesis is focused on the analysis of the AUTOMARKET TRUCKS s.r.o. company with the suitable methods. Based on them there are suggestions to improve the current situation of the AUTOMARKET TRUCKS s.r.o. which was found from the analysis results.
283

Přínosy optimalizace řízení zásob a jejich skladování / The Benefits of Optimizing Inventory Management and Storage

Salvet, Zdeněk January 2011 (has links)
In this diploma thesis there is fisrtly introduced company for which single proposals are solved and the materiál standard, actual ways of storage and absences which are solved in the proposal as well. It is also important for storage to know technological processes of production and placing of production equipment. On the basis of teoretic findings there were solution proposed which optimise processes of storage and its control. Results are: better-arranged storage, increased capacity of the storage of base material and products and reengineering of gathering of information which are important for the control of storage.
284

Analýza ztráty zisku dopravní organizace v důsledku opravy po nehodě u vozidel nad 12 t celkové hmotnosti / Analysis of Profit Loss for a Transport Organization as a Result of Repair Work After an Accident Involving Vehicles with a Total Weight of over 12 t

Svozil, Milan January 2012 (has links)
This thesis, as a part of the overall project to determine general methodology for calculating lost profits, deals with technical and economic data of trucks, cost analysis and quantification of lost profits after an accident and subsequent mending. It focuses on vehicles with a total weight of over 12 tons. The thesis and its results are beneficial for the experts and forensic engineering experts who, based on documents can more easily determine a methodology for calculating lost profits. It simplifies and accelerates the settlement of claims for loss of profits and payments.
285

Digital mirrors : Supplementary information to increase driver’s awareness of surroundings / Digitala speglar : Kompletterande information för ökning av förarens medvetenhet om omgivningen

Payandehmehr, Bahare, Placzkowska, Marta January 2015 (has links)
Replacement of physical rear-view mirrors with digital offer new possibilities for vision enhancements and supplementary information that could facilitate driving. However, the invehicle support systems and information contribute to increased mental workload of the driver and inadequate Human Machine Interface (HMI) can lead to distraction and impaired driving performance. Therefore, it is crucial to explore what relevant information can be implemented and how it should be designed regarding cognitive ergonomics to promote human information processing. The aim of the project was to create one or more concepts for supplementary information that could be implemented in the digital mirrors in order to increase driver’s awareness of the surroundings and therefore contribute to improved road safety. The design process consisted of a pre-study regarding cognitive ergonomics followed by three iterations including user interaction, literature studies, concept generation and evaluation with respect to acquired theoretical knowledge and tests with professional truck drivers. This approach allowed for identification of user demands and development a refined user oriented solution. The final concept was evaluated in a driving simulator with ten truck drivers to investigate potential effects on driver performance regarding detection of obstacles in blind spots, vehicle control and subjective opinions considering perceived mental workload and user acceptance. The evaluation resulted in significantly improved detection rate of vehicles in blind spots with the developed concept. Longitudinal and lateral vehicle control was not affected hence, the additional information did not distract the drivers. Furthermore, the drivers perceived mental workload was not increased and the user acceptance was significantly improved after the test indicating that drivers’ expectations were met and furthermore exceeded. The results of the study suggest that supplementary information in digital mirrors can be beneficial for improving driver’s awareness of the surroundings and should be further investigated. / Ersättning av fysiska backspeglar i lastbilar skapar förutsättningar för kompletterande visuell information som kan bidra till säkrare körning. Informationskällor i fordon kan vara en bidragande faktor till ökad mental belastning hos förarna och bristfällig användargränssnitt kan leda till distraktion och nedsatt körprestation. Därmed är det väsentligt att undersöka vilken typ av visuell information som kan implementeras i de digitala speglarna samt hur den ska utformas med avseende på kognitiv ergonomi. Syftet med denna studie var att undersöka vilken relevant information som kan inkluderas i de digitala speglarna för att bidra till ökad medvetenhet om omgivningen hos förarna och därmed till ökad trafiksäkerhet. Utvecklingsprocessen bestod av en förundersökning av de ergonomiska aspekterna följd av tre iterationer bestående av användarundersökning, litteraturstudier, generation av koncept samt utvärdering utifrån erhållen teoretisk kunskap och användartester med yrkesförare. Denna metod möjliggjorde att identifiera användarkrav och utveckla en lösning anpassad efter förarnas behov. Det slutliga konceptet utvärderades i en körsimulator med tio lastbilschaufförer för att undersöka dess potentiella effekter på förarens prestationsförmåga med avseende på detektering av hinder i döda vinklar, fordonskontroll och subjektiva åsikter angående mental arbetsbelastning och användaracceptans. Resultaten påvisade signifikant förbättring av detektion av fordon i de döda vinklarna med det utvecklade konceptet. Kontrollen av fordonet påverkades ej vilket tyder på att informationen inte upplevdes som distraherande. Den subjektiva mentala belastningen ökades inte och användaracceptansen förbättrades signifikant efter testet vilket indikerar att förarnas förväntningar uppfylldes. Resultaten av studien tyder på att kompletterande information i digitala speglar kan vara fördelaktig för att förbättra förarnas medvetenhet om omgivningen och bör utredas vidare.
286

On Electrification of Heavy-Duty Trucks : A Grid Impact Analysis of Grid Integration of a High-Power Charging Station

Arvidsson, Maria January 2022 (has links)
The Swedish transport sector will need to undergo a major restructuring to achieve the established climate and environmental goals. The biggest change is that fossil fuels will be phased out and a larger part of the vehicle fleet will be electrified. This study deals with the electrification of heavy-duty trucks and how high-power charging stations affect the local electricity grid. Charging of heavy-duty trucks depends largely on the logistics of the transport system, which reduces the demand flexibility of power. High-power charging entails a risk of increased power peaks, which can affect the bus-voltage profiles, losses and loads on grid components. This thesis has been conducted as general study based on the case with the high-power charging station at Vädermotet in the area Hisingen of Gothenburg. The purpose was to build a generic model of the electricity grid at Hisingen and then investigate the consequences of high-power charging for the grid for two charging scenarios: the first scenario with four ABB Terra 360 chargers, and the second scenario with six ABB Terra 360 chargers and one MCS. The electricity network model and simulations were performed in PSS®SINCAL. The two charging scenarios, as well as the scenario before chargers were installed, were then simulated for three different system-load cases: maximum, average, and low load. The results showed that high-power charging of trucks had the biggest impacts for the voltage profiles during the case of low load. For the medium load and maximum load cases, the effect of the high-power charge decreased. Furthermore, electricity network losses increased for the low load case, but decreased slightly for the average and maximum load case. The reason was a more even load balance between the bus that connected the charging station to the grid and the rest of the network for the average and maximum load cases. In summary, the study indicated that grid implementation of a high-power charging station will have consequences for the local power system. However, the magnitude of the effects is not validated and can therefore only be regarded as indications. The outcome can be partly explained by the assumptions and simplifications of the model compared to the real system.
287

Self-Adaptive Algorithm for Warehouse Truck Speed Measurement with Accelerometer / Adaptiv algoritm för accelerometerlös mätning av hastighet av lagertruckar

Zhao, Shuqi January 2015 (has links)
Warehouse trucks are now a practical equipment for lifting and moving goods in warehouses. The working situation for warehouse trucks is complicated. Spilling of machine oil or liquid product leads to low friction coefficient of the floor. Warehouse floors are normally made of concrete. Smooth concrete floors easily become slippery with liquid on the surface. With several tons of load on the fork, the braking distance is longer. An Anti-lock Braking System(ABS) for the truck control system is needed concerning the safety of the operator and people surrounding the truck. The warehouse truck braking is realized by controlling the motor torque. In order to control the torque, the truck wheel slip ratio is needed. With an accurate slip ratio, the control system will have accurate information regarding the vehicle status. To calculate the slip ratio, both the vehicle speed and wheel speed is needed. The wheel speed is derived from the motor speed. The vehicle speed is the challenge of this project. For normal passenger vehicles, sensors are installed on the trailer wheel where no slip occurs. In this case, the requirement is to use a lower number of sensors. There are two reasons of this requirement. It reduces the installation complexity and the cost of the control system. According to the literature study, a sensorless ABS system is impossible realize. Without sensor, it is not possible to estimate the vehicle status. One accelerometer is used in this project. An algorithm is designed and implemented in MATLAB. This algorithm solves the problem with zero-point drifting. Additional features are also added to the algorithm. The algorithm is a self-adaptive algorithm. It operates independently of the installation position of the accelerometer, without additional sensors. The result of the experiment with real measurements is very good. Future work on how to rewrite the algorithm from MATLAB programming to C programming is suggested in the end. Methods of implementation of the algorithm are also recommended. / Lagertruckar är en praktisk utrustning för att lyfta och flytta gods på ett lager. Arbetssituationen för en lagertruck är komplicerad. Oljespill eller spill av vätskor i allmänhet innebär att friktionskoefficienten för golvet blir låg. En förklaring till att golvet påverkas mycket av spill är att ytan är mycket slät eftersom den vanligvis är ett obehandlat betonggolv. Med flera ton last på gaffeln kan bromssträckan bli avsevärt längre om golvet är halt. För att uppnå tillräcklig säkerhet för föraren och personer i truckens omgivning skulle ett anti-låsningssystem (ABS) för bromsfunktionen vara nödvändig. Bromsfunktionen hos lagertrucken ombesörjs genom styrning av motormomentet. För detta ändamål är det nödvändigt att känna till drivhjulets âslipâ. Om denna storhet är känd med god noggrannhet kan styrsystemet få god information om fordonets status. För att kunna bestämma drivhjulets âslipâ krävs information om såväl fordonets hastighet som drivhjulets varvtal. Drivhjulets varvatl kan bestämmas mha motorvarvtalet. Fordonets hastighet är utmaningen i detta arbete. För normala passagerarfordon installeras varvtalsgivare på ett hjul som inte har drivning, eftersom detta inte har något âslipâ. I detta fall krävs emellertid att ett lägre antal sensorer ska användas. Det finns två skäl till detta krav. För det första minskas komplexiteten av installationen och för det andra minskas kostnaden. Enligt litteraturstudien är det omöjligt att realisera ett sensorlöst ABS-system. Utan givare kan fordonets status inte bestämmas. I detta projekt används därför en accelerometer. En algoritm har tagits fram och implementerats i MATLAB. Denna algoritm löser problemet med s.k. âzero-point driftningâ. Ytterligare funktioner har också lagts till i algoritmen. Algoritmen är själv-uppdaterande. Den fungerar oberoende av positionen av acelerometern utan ytterligare sensorer. Resultatet av mätningen en mycket bra. I framtiden kan MATLAB-koden ersättas med C-kod. Metoder för implementering av algoritmen föreslås också.
288

Haul road defect identification and condition assessment using measured truck response

Hugo, Daniel 16 July 2008 (has links)
Mine haul road maintenance is traditionally done at scheduled intervals or after regular inspection. Both these methods can lead to unwarranted expenditure, either through over-maintaining the road, or failure to recognise significant deterioration, resulting in an increase in vehicle operating costs. Predictive maintenance management models for unpaved roads have been developed in recent years. These methods work well in a trivial environment where variables such as traffic volume can be predicted. However, many mining systems are too complex for such models to be effective. This work investigates the possibility of using haul truck response to aid haul road maintenance management. The approach adopted for the study was twofold: Firstly, can truck response data be used to recognise specific road defects, in terms of location, type and size? This is important since different defect types require different road maintenance strategies. Secondly, can road roughness be measured on a qualitative basis? With the emphasis on road defect reconstruction, a mathematical modelling approach was adopted. The truck was characterised in terms of its suspension and tyre properties. Dynamic truck response data was acquired during field measurements in which the vehicle was driven over defects of known dimensions. With these data sets available, mathematical modelling and simulation was possible. Quarter vehicle and seven degree of freedom vehicle models played a vital role in this work by laying a foundation in the use of haul truck response for the purpose of road defect reconstruction. A modelling methodology that is based on dynamic equilibrium of an independent front unsprung mass of the truck is proposed in which the vertical dynamic tyre force and eventually the road geometry is calculated. It is shown that defects can be reconstructed from measured truck response data with an accuracy sufficient to fulfil the requirements of defect recognition for road maintenance management purposes. Secondly, a preliminary investigation into the qualitative assessment of road condition via truck response measurements was conducted. The inherent response properties of the truck pertaining to road roughness measurement were studied and some correlation between measured suspension motion and road roughness measured with a high speed profilometer was found. / Dissertation (MEng (Mechanical))--University of Pretoria, 2005. / Mechanical and Aeronautical Engineering / MEng / Unrestricted
289

Strategic management of intellectual property in the field of vehicle autonomy and connectivity : A case study in the truck manufacturing field

Åkerblom, Philip January 2021 (has links)
The truck manufacturing field is expected to go through a disruptive change in the coming decade(s) due to a predicted implementation of autonomous (self-driving) heavy-duty vehicles. Here, companies face a challenge in that autonomous vehicles (AV) will include technologies and competences from multiple industries. This will most likely have an impact on how companies manage their intellectual property (IP) to protect their inventions if they wish to keep up with the changing market. To do this in the most optimal way, it is argued that a company’s IP-strategy needs to be incorporated into their business strategy. At the same time, studies show that companies are experiencing difficulties in extracting the full potential of their IP-management. Hence, this master thesis aims at investigating how a truck manufacturing company can adapt their IP-management policy in line with future developments within these emerging technologies and how their IP-strategy can become intertwined with their business strategy. Next to a literature review of these fields, the thesis conducts a qualitative case study of a truck manufacturer that intends to be part of this change based on 11 semi-structured interviews. From the empirical results, the company’s decision-making process regarding IP is identified, whereby this thesis suggests four points of improvement that could make their IP-management policy more effective. Further, this study presents three actions that can be taken in a company to incorporate their IP-strategy with their overall business strategy. The study ends with giving suggestions for future research and presenting six managerial implications that would come by implementing the suggestions made in this thesis.
290

Autonomous transportation for a Swedish production facility : Mapping the technological and regulatory hurdles

Fredriksson, Karl January 2021 (has links)
The technology of autonomous vehicles has the potential to provide a significant number of safety, efficiency and environmental benefits to those who are able to harness it. As such, it is only natural that the company which is the subject of this project should want to explore this field, since the company prides itself on being at the cutting edge of both environmental sustainability and technological advancement. This inquiry was therefore launched in order to amass a sufficient knowledge base to enable management to make informed decisions about the possible future implementation of autonomous trucks, specifically to handle the logistics flow between their production facility in Skellefteå, Sweden and the nearby harbour. The first step to achieving this objective consisted of an exploration of the state of autonomous vehicle technology as well as the regulatory framework in Sweden for operating such systems on public roadways. Information was gathered from a vast array of sources, including academic literature, official reports from various authorities, journalistic publications as well as interviews with individuals with competence or experience within this field. While the regulatory situation in Sweden at the moment offers no legal way to operate autonomous vehicles on public roads, it is possible to be granted permission to perform trials of this technology under certain conditions. An investigation was undertaken to determine whether this might be a viable option for the company’s case. As such, hazard analysis was performed on the proposed route in Skellefteå. The method for this was based off of methodology gained from sources who had previously executed safety cases for trials of autonomous technology. A list of potential hazards relevant to the operation of autonomous vehicles was composed, together with variables with which to measure their severity. The relevance and appropriate scope of these hazards and variables was then verified by discussing it with sources with competence in this field. The route was then travelled in order to observe the prevalence of the aforementioned variables. The information was completed and verified through various reports gathered from the Swedish Transport Administration and the Swedish Meteorological and Hydrological Institute. The result of the inquiry was that the autonomous technology on the market today is not sufficiently advanced to handle the specified application with an adequate level of safety. The route is also of limited use in establishing trials for testing of autonomous vehicles. While there are uses for autonomous transportation technology, great breakthroughs are needed before the technology reaches the level needed to handle such complex challenges as would be encountered on the proposed application. / Självkörande fordon är en teknologi som visar potential för betydande fördelar inom säkerhet, effektivitet och miljömässigt för dem som kan tygla den. Det framstår därför som naturligt att uppdragsgivaren till detta projekt skulle vara intresserad av denna teknik, då företaget är känt för att vara vid både miljö- och teknikfrågornas framkant. Därför lanserades detta utredningsarbete för att sammanställa tillräcklig kunskap för att kunna ta informerade beslut om en potentiell implementering av ett autonomt transportsystem från deras fabrik i Skellefteå till Skelleftehamn. Denna utredning började med att kartlägga hur autonoma fordonstekniken ser ut idag, samt de regulatoriska möjligheterna att driva autonoma system på allmän väg I Sverige. Informationen samlades från en mängd olika källor, inklusive akademisk litteratur, rapporter från officiella källor, journalistiska källor samt från intervjuer med personer som besitter kompentens och erfarenhet av ämnet. Emedan den regulatoriska situationen i Sverige för stunden inte medger något lagligt sätt att operera självkörande fordon på allmän väg så finns det möjlighet att få tillstånd att utföra försöksverksamhet med sådana fordon så länge vissa villkor uppfylls. En utredning genomfördes för att fastslå om sådan verksamhet skulle kunna vara relevant i företagets fall. I och med detta så utfördes en riskanalys på den föreslagna rutten i Skellefteå. Metoden för dess utförande baserades på metodologi som hämtades från källor som tidigare hade utfört säkerhetsbevisningar för försöksverksamhet på autonoma fordon. En lista av möjliga risker framtogs, tillsammans med mätpunkter vilka skulle kunna användas för att fastslå deras betydelse för autonom fordonteknologi. Dessa riskers relevans och lämpligheten av dess omfattning diskuterades därefter med källor med kompetens inom området. Sedan besöktes rutten för att observationer om mätpunkternas förekomst kunde utföras. Informationen kompletterades och verifierades därefter med information från ett antal rapporter från Trafikverket och Sveriges Meteorologiska och Hydrologiska Institut. Det man kommit fram till är att det idag inte finns något autonomt fordonssystem som är tillräckligt avancerat att klara rutten mellan fabriken och hamnen med god nog säkerhet. Rutten är dessutom av begränsat värde vad det gäller att testa sådana system. Även om det finns autonoma system i operation i dagsläget så ligger dock tekniken långt under den nivå som skulle behövas för att ta sig an de utmaningar som skulle uppstå I det föreslagna användningsområdet.

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