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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.
481

Integrating Weather Conditions in Truck Route Optimization : Maximizing Utilization and Cost-effectiveness

Stenbratt, Sigrid, Lundell, Paulina January 2023 (has links)
Abstract The focus of the thesis is researching how to optimize a certain route, highlighting theimportance of weather conditions in the context of optimizing truck routes. Additionally, itemphasizes the goals of maximizing human utilization and cost-effectiveness. The project teamconducted a survey on fuel habits, and the results showed that the participating companies lackeda defined strategy for the company's fuel habits or a specific approach for selecting fuelingcompanies. The project team developed an algorithm that assists drivers in selecting the mostoptimized routes while enabling companies to calculate these routes efficiently. Data wascollected on the fuel consumption associated with the loading and unloading of goods. The totalroute cost is calculated using a custom equation that includes the driver´s salary, the employer´ssocial security contribution, the cost of the truck when loading and unloading, and the wear onthe truck. The company naturally expects to generate a profit, and such profit margins may differamong companies. Therefore, the project team excluded this factor from the equation todetermine the route's cost. The findings showed that varying weather conditions did impactconsumption, thereby influencing the final cost. The algorithm that the project team made is asignificant milestone toward the completion of the final product. However, there are still a fewremaining steps to be taken in order to achieve the desired end result and future development.
482

Development of a Heavy Truck Vehicle Dynamics Model using Trucksim and Model Based Design of ABS and ESC Controllers in Simulink

Rao, Shreesha Yogish 11 July 2013 (has links)
No description available.
483

Sharing Sales and Service Networks with Competitors : A Multiple-case Study in the Heavy Truck Industry / Att dela sälj- och servicenätverk med konkurrenter

ENGBLOM, ALEXANDER, LUNDQUIST, EMMA January 2018 (has links)
In the heavy truck industry, sales and service networks play an important role. Investments in network infrastructure are costly, and to be profitable, there is a critical service volume to fulfil. This is especially challenging in new markets, where service demand is low and uncertain. A possible solution is to share sales and service networks with competitors. Simultaneous cooperation and competition, co-opetition, is a complex and contradictory phenomenon that has been previously researched, but with focus on cooperation in input activities like R&D. This thesis investigates co-opetition in output activities, in sales and services, by analysing how heavy truck companies could form competitor partnerships in sales and service networks. This is done by a literature review and a multiple case study. From the analysis, a framework for assessing and designing potential competitor partnerships is presented. The framework consists of seven factors that are significant for competitor partnership success in sales and service networks; cultural fit, noncompeting products, compatible goals, excess network capacity, dedicated salespersons, high commitment, and patient implementation. This thesis contributes to science by research on co-opetition research in output activities, and by a discussion on the meaning of competition, success and partnerships. / I tunga lastbilsbranschen spelar sälj- och servicenätverk en viktig roll. Investeringar i nätverken är dyra, och för att vara lönsamma krävs en viss servicevolym. Det är särskilt utmanande på nya marknader, där efterfrågan är låg och obestämd. En möjlig lösning är att dela sälj- och servicenätverk med konkurrenter. Simultant samarbete och konkurrens, så kallad co-opetition, är ett komplext och motsägande fenomen, som tidigare forskats på med fokus på samarbete inom utveckling. Denna uppsats undersöker co-opetition inom sälj, genom att titta på hur tunga lastbilsföretag kan ingå partnerskap inom sälj- och servicenätverk tillsammans med konkurrenter. Detta görs genom en litteraturgenomgång samt en flerfallstudie. Utifrån vår analys presenteras ett ramverk för att bedöma och utforma potentiella partnerskap med konkurrenter. Ramverket består av sju viktiga faktorer för framgångsrika partnerskap inom sälj- och servicenätverk tillsammans med konkurrenter; kulturell passform (cultural fit), icke-konkurrerande produkter, kompatibla mål, överbliven kapacitet i nätverket, dedikerade säljare, högt engagemang och tålmodig implementering. Uppsatsen bidrar till forskning inom co-opetition inom sälj och med diskussion kring begreppen konkurrens, framgång och partnerskap.
484

Traveling Salesman Problem with Single Truck and Multiple Drones for Delivery Purposes

Rahmani, Hoda 23 September 2019 (has links)
No description available.
485

Behavior of Adjacent Prestressed Concrete Box Beam Bridges Containing Ultra High Performance Concrete (UHPC) Longitudinal Joints

Semendary, Ali A. 13 July 2018 (has links)
No description available.
486

Exhaust Emissions Analysis for Ultra Low Sulfur Diesel and Biodiesel Garbage Trucks

Garimella, Venkata Naga Ravikanth January 2010 (has links)
No description available.
487

Analysis of the energy consumption of the powertrain and the auxiliary systems for battery-electric trucks / Analys av energiförbrukningen i drivlinan samt för hjälpsystemen för batterielektriska lastbilar

Song, Guanqiao January 2020 (has links)
The electrification of the truck is crucial to meet the strategic vision of the European Union (EU) to contribute to net-zero greenhouse gas emissions for all sectors of the economy and society. The battery-electric truck is very efficient to reduce the emissions and has also a lower Total Cost of Ownership (TCO) compared to diesel trucks. Thus, the energy consumption of the battery-electric truck needs to be analysed in detail, and the differences in the conventional powertrain, recuperation by regenerative braking during driving and charging during standing, need to be considered. This master thesis aims to analyse the energy consumption of the battery-electric truck during driving and standing charging. For driving cycle simulation the Vehicle Energy Consumption calculation TOol (VECTO) and MATLAB are used. Different variations, such as payload, rolling resistance, air drag, and Power Take Off (PTO), are considered in the driving cycle simulation. The driving cycle simulation is verified by calculating the energy balance and compared with the on-road test results. For the standing charging simulation, MATLAB is used to analyse the charging loss with different battery packs and charging speeds. The results are shown with the Sankey diagram and other illustrative tools. Seen from the simulation results, the usable energy of the battery pack is enough for the truck to complete the designed driving cycle. The main loss in the powertrain is the Power Electronic Converter (PEC) and the electric machine. To increase the range and reduce energy loss, using a higher efficiency PEC and electric machine is an efficient method. For the charging simulation, the current Combined Charging System (CCS) standard charging station can charge the battery-electric truck with adequate voltage and reasonable charging time. The main loss during the charging comes from the charging station. / Elektrificering av lastbilen är avgörande för att uppfylla Europeiska Unionens (EUs) strategiska vision att bidra till nettonollutsläpp av växthusgaser för alla sektorer i samhället. Den batterielektriska lastbilen är väldigt effektiv för att reducera utsläppen och är också mer ekonomisk med en lägre Total Cost of Ownership (TCO) jämfört med diesel lastbilar. Således behöver energiförbrukningen för den batterielektriska lastbilen analyseras i detalj, och skillnaderna i den konventionella drivlinan, återhämtning genom regenerativ bromsning under körning och laddning, måste övervägas. Detta examensarbete syftar till att analysera energiförbrukningen för den batterielektriska lastbilen under körning och laddning. För körcykelsimuleringar används the Vehicle Energy Consumption calculation TOol (VECTO) och MATLAB. Olika variationer, såsom nyttolast, rullmotstånd, luftmotstånd och Power Take Off (PTO), beaktas i körcykelsimuleringen. Körcykelsimuleringen verifieras genom att beräkna energibalansen som jämförs med experimentella testresultat utförda på väg. För laddningssimuleringen används MATLAB för att analysera laddningsförlusten med olika batteripaket och laddningshastigheter. Resultaten visas med Sankey diagram och andra illustrativa verktyg. Simuleringsresultaten visar att batteripaketets användbara energi är tillräckligt för att lastbilen ska kunna slutföra den planerade körcykeln. Den största förlusten i drivlinan är kopplat till the Power Electronic Converter (PEC) och den elektriska maskinen. För att öka räckvidden och minska energiförlusten är det ett effektivt sätt att en använda PEC och en elektrisk maskin med högre effektivitet. För laddningssimuleringen kan den nuvarande stationen med Combined Charging System (CCS) standard ladda batteriladdaren med tillräcklig spänning och med rimlig laddningstid. Huvudförlusten under laddningen kommer från laddstationen.
488

Improvement of Driver’s Climate Comfort in Larger Truck’s Cabin / Förbättring av förarens klimatkomfort i störrelastbilshytt

García, César January 2024 (has links)
The purpose of this thesis work is to improve the perceived climate comfort in larger truck cabins since the European commission’s new stronger carbon dioxide standards have introduced an update to the EU 96/53 directive. This directive increases the dimensions and weights of heavy truck motor vehicles, extending the driver’s cabin length by 500 mm in order to increment the truck’s energy efficiency and aerodynamics. This update was seen also as an enabler to improve the truck driver’s performance, comfort and preference towards Scania. Since the cabin of the truck is to be considered the place where the driver spends the most of its time, ensuring the driver’s comfort when resting inside means to ensure the accomplishment of their labor safely. One system used to provide comfort in the cabin when resting is the climate control unit. This unit creates an inner climate controlled environment by providing warm or cool air through an installed Heating Ventilation and Air Conditioning (HVAC) system. In order to introduce a new auxiliary unit, the design thinking methodology was chosen. This allowed to ground the proposed concepts on the actual needs of the final users. Based on their input, the aforementioned concepts were analyzed and downsized in order to prototype and test the selected ones. The final concepts of a 500 mm larger cabin were tested in a climate chamber under warm and cold conditions: 37°C and -15°C respectively. Then, these concepts were compared against the short cabin (current cabin) and the 500 mm larger cabin without any mounted prototype. During each test, a thermal manikin was placed in the cabin’s bed in order to obtain not only temperature readings, but also the estimated comfort that the user would sense under these circumstances. As it could be expected, the 500 mm larger cabin without any added concept presented a temperature degradation of the current HVAC system compared to the short cabin. The areas of temperature concentration (warm or cold) were identified, being the rear wall of the cabin the most affected. The implementation of the concepts compared to the larger cabin gave positive results, reducing the time to reach the set temperature in the HVAC system controls in both warm and cold environments. The analysis of the results lead to the conclusion that the enlargement of a truck creates a need to maintain or improve the behavior of its HVAC system. The implementation of an auxiliary unit to the main system in the rear of the cabin showed not only temperature enhancements, but also a thermal comfort improvement for the user, allowing it to rest and therefore, to fulfill its tasks with the best mental and physical conditions. / Syftet med det här examensarbetet är att förbättra den upplevda klimatkomforten i större lastbilshytter sedan EU-kommissionens nya hårdare koldioxidstandarder har medfört en uppdatering av EU-direktivet 96/53. Detta direktiv ökar dimensionerna och vikterna för tunga lastbilar och förlänger förarhyttens längd med 500 mm för att öka lastbilens energieffektivitet och aerodynamik. Denna uppdatering sågs också som en möjlighet att förbättra lastbilschaufförens prestation, komfort och inställning till Scania. Eftersom lastbilshytten är den plats där föraren tillbringar den största delen av sin tid, är det viktigt att säkerställa förarens komfort när han eller hon vilar i hytten för att kunna utföra sitt arbete på ett säkert sätt. Ett system som används för att ge föraren komfort när han eller hon vilar i hytten är klimatenhet. Denna enhet skapar en inre klimatkontrollerad miljö genom att tillföra varm eller kall luft via ett installerat HVAC-system (Heating Ventilation and Air Conditioning). För att introducera ett nytt hjälpenhet valdes metodiken design thinking. Detta gjorde det möjligt för de föreslagna koncepten att baseras på de faktiska behoven hos de slutliga användarna. Baserat på deras input, gjordes analyser av de tidigare nämnda koncepten för att sedan välja ut, prototypa och testa de utvalda. De slutliga koncepten med en 500 mm större hytt testades i en klimatkammare under varma och kalla förhållanden: 37°C respektive -15°C. Därefter jämfördes dessa koncept med den korta hytten (nuvarande hytt) och den 500 mm större hytten utan någon monterad prototyp. Under varje test placerades en klimatdocka i hyttens säng för att inte bara få temperaturavläsningar, utan också den uppskattade komfort som användaren skulle känna under dessa omständigheter. Som väntat uppvisade den 500 mm större hytten utan något extra koncept en temperaturförsämring av det nuvarande HVAC-systemet jämfört med den korta hytten. Områdena med varm eller kall temperatur identifierades och kabinens bakre vägg var den som påverkades mest. Implementeringen av koncepten jämfört med den större hytten gav positiva resultat, vilket minskade tiden för att nå den inställda temperaturen för HVAC-systemet i både varma och kalla miljöer. Analysen av resultaten ledde till slutsatsen att förstoringen av en lastbil skapar ett behov av att bibehålla eller förbättra beteendet hos dess HVAC-system. Implementeringen av en hjälpenhet till huvudsystemet i den bakre delen av hytten visade inte bara temperaturförbättringar, men också en förbättring av klimatkomforten för användaren, vilket gör att föraren den kan vila och därmed utföra sina uppgifter med de bästa mentala och fysiska förutsättningarna.
489

O mercado de caminhões no Brasil: um estudo econométrico dos determinantes das vendas de veículos

Gonçalves, Carlos Aurélio Bustamante 17 November 2016 (has links)
Submitted by Carlos Aurélio Bustamante Gonçalves (carlos.a.b.goncalves@gmail.com) on 2016-12-01T22:33:16Z No. of bitstreams: 1 carlos gonçalves - Dissertação - o mercado de caminhões no brasil -01122016.pdf: 3390001 bytes, checksum: df0eedc2484f2a8784dda76039181601 (MD5) / Rejected by Fabiana da Silva Segura (fabiana.segura@fgv.br), reason: Boa Noite, Prezado Carlos Peço corrigir alguns itens de formatação conforme segue: - Excluir o acento do nome Getulio nas páginas - Nome deve ser em maiúsculo (alternar, nas páginas que tiver o nome) - Titulo também em fonte maiúscula (alterar nas páginas que contém o título) - No rodapé permanece somente São Paulo - excluir o - SP - Linha de Pesquisa: Finanças e Economia de Empresas, alterar nas páginas que contém a lnha - Excluir na contra capa abaixo no nome do orientado FGV - EAESP - Folha de Assinaturas, alterar a linha de pesquisa e colocar a data de aprovação: 17/11/2016 Peço proceder com as alterações e submeter o trabalho novamente on 2016-12-01T23:28:13Z (GMT) / Submitted by Carlos Aurélio Bustamante Gonçalves (carlos.a.b.goncalves@gmail.com) on 2016-12-02T02:34:57Z No. of bitstreams: 1 carlos gonçalves - Dissertação - o mercado de caminhões no brasil -02122016.pdf: 3391454 bytes, checksum: 7cdcde7e62ecc28be15ec876866cca96 (MD5) / Approved for entry into archive by Fabiana da Silva Segura (fabiana.segura@fgv.br) on 2016-12-02T14:03:17Z (GMT) No. of bitstreams: 1 carlos gonçalves - Dissertação - o mercado de caminhões no brasil -02122016.pdf: 3391454 bytes, checksum: 7cdcde7e62ecc28be15ec876866cca96 (MD5) / Made available in DSpace on 2016-12-02T18:40:07Z (GMT). No. of bitstreams: 1 carlos gonçalves - Dissertação - o mercado de caminhões no brasil -02122016.pdf: 3391454 bytes, checksum: 7cdcde7e62ecc28be15ec876866cca96 (MD5) Previous issue date: 2016-11-17 / Este estudo trata do comportamento da demanda por caminhões novos no Brasil no período de 1996 a 2015 e da investigação dos fatores que a influenciam. Tal questão é relevante devido à escassez de estudos acerca deste tema, ainda que se trate do modo historicamente predominante de transporte de carga no país. O objetivo de pesquisa é determinar e quantificar os fatores que provocam o aumento ou diminuição das vendas de caminhão no Brasil. Para atingir este objetivo, foram construídos modelos econométricos a partir de dados secundários. Proxies utilizadas em outros modelos de demanda automotiva foram confirmadas e refinadas, enquanto novas proxies foram introduzidas com sucesso. Quanto aos resultados, este estudo inovou ao identificar três tipos de determinantes, e ao detalhar os efeitos e defasagens de suas influências: variáveis relacionadas especificamente ao mercado de caminhões, variáveis relacionadas ao PIB e variáveis relacionadas à confiança do comprador. Adicionalmente, realizou-se uma verificação da causalidade entre crédito e vendas, com o surpreendente resultado de que a influência ocorre no sentido de vendas para crédito. Com estes resultados, este estudo dissemina o conhecimento a respeito do comportamento do mercado a toda a cadeia produtiva, melhorando a qualidade das decisões e proporcionando aumento da eficiência para o sistema como um todo. / This is a study on the demand for new trucks in Brazil from 1996 to 2015, and an investigation on the factors that influence it. This topic is relevant due to the scarcity of studies concerning the subject, and due to the overwhelming domination of trucks in cargo transport in Brazil. It aims identify and quantify the variables that drive the sales of trucks. To reach this goal, econometric models were constructed based on secondary data. Variables usually adopted in other studies on automotive demand were confirmed and even refined and new variables were successfully introduced. This study innovates by identifying three groups of variables, and by detailing the effects and the lags of their influence: variables specific to the truck market, variables related to GDP, and variables related to the decision maker’s confidence. Additionally, a causality analysis involving credit and truck sales was performed, unexpectedly resulting in sales causing credit. Through these results, this study disseminates knowledge about the behavior of the truck market to the entire productive chain, contributing to evolve the quality of decisions and the efficiency of the entire system.
490

Complex Vehicle Modeling: A Data Driven Approach

Alexander Christopher Schoen (8068376) 31 January 2022 (has links)
<div> This thesis proposes an artificial neural network (NN) model to predict fuel consumption in heavy vehicles. The model uses predictors derived from vehicle speed, mass, and road grade. These variables are readily available from telematics devices that are becoming an integral part of connected vehicles. The model predictors are aggregated over a fixed distance traveled (i.e., window) instead of fixed time interval. It was found that 1km windows is most appropriate for the vocations studied in this thesis. Two vocations were studied, refuse and delivery trucks.</div><div><br></div><div> The proposed NN model was compared to two traditional models. The first is a parametric model similar to one found in the literature. The second is a linear regression model that uses the same features developed for the NN model.</div><div><br></div><div> The confidence level of the models using these three methods were calculated in order to evaluate the models variances. It was found that the NN models produce lower point-wise error. However, the stability of the models are not as high as regression models. In order to improve the variance of the NN models, an ensemble based on the average of 5-fold models was created. </div><div><br></div><div> Finally, the confidence level of each model is analyzed in order to understand how much error is expected from each model. The mean training error was used to correct the ensemble predictions for five K-Fold models. The ensemble K-fold model predictions are more reliable than the single NN and has lower confidence interval than both the parametric and regression models.</div>

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