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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.
51

Alocação e dimensionamento de frotas de veículos para apoio a maquinário agrícola de usinas sucroalcooleiras / A method to quantify the vehicles fleet to support the agricultural machines in sugar-cane industries

Ugo Leandro Diniz 12 September 2000 (has links)
As usinas sucroalcooleiras utilizam grandes áreas para o cultivo da cana-de-açúcar, conhecidas como fundos agrícolas. Nesses fundos agrícolas, as atividades são realizadas por uma grande quantidade de máquinas agrícolas diferentes. As necessidades dessas máquinas, como combustível, óleo lubrificante e outras, são supridas pelos comboios de manutenção. Este trabalho visa propor um método para alocação e dimensionamento da frota de comboios de manutenção para o atendimento às máquinas. Para tanto foi utilizado um Sistema de Informações Geográficas aplicado a transportes (SIG-T), denominado comercialmente por TransCAD. Um estudo de caso foi realizado na Usina da· Barra S.A., localizada no município de Barra Bonita, centro oeste do Estado de São Paulo. Diversas simulações de atendimento, com configurações diferentes de distribuição das máquinas, foram realizadas. O atendimento às situações reais de distribuição das máquinas também foi analisado, com o objetivo de confrontar os dados reais de atendimento com os resultados obtidos através da aplicação da metodologia proposta. Foram obtidas as rotas e, conseqüentemente, o número de comboios necessários para o atendimento no período de safra e de entressafra. Com relação à aplicação do TransCAD na roteirização, pode-se constatar uma redução de até 19,6% na distância total percorrida pela frota de comboios no primeiro turno de trabalho em um dos dias analisados. / The sugar-cane industries use large areas for the cultivation of the sugar-cane. In these areas, different agricultural machines carry out several activities. The basic needs of these machines, such as fuel, lubrication and others, are supplied by a fleet of vehicles. The objective of this work is to propose a method to analyze the number of vehicles to compose the fleet already mentioned, based on the application of a Geographical lnformation System (GIS), commercially denominated by TransCAD. A case study was done in the Usina da Barra S.A. company, located at Barra Bonita city, State of São Paulo. Several situations of attendance were simulated with different distribution of machines, based in the initial annual planning of the company. We also analyzed the attendance of real distribution of machines with the objective of comparing the results obtained through the application of the proposed method and the real operation. The routes were obtained and, consequently, the necessary number of vehicles for the attendance. In relation to the application of TransCAD in the routing, a reduction of 19,6% was verified in the total distance traveled by the fleet of vehicles.
52

Συγκριτική μελέτη της δομής και δυναμικής του αλιευτικού στόλου των κρατών-μελών και των εξαρτώμενων από την αλιεία περιοχών της Ε.Ε.

Πούλος, Κωνσταντίνος 23 October 2008 (has links)
Η παρούσα μελέτη έχει ως στόχο τη διερεύνηση της δυναμικής του αλιευτικού στόλου της Ελλάδας και άλλων κρατών-μελών της Ευρωπαϊκής Ένωσης (Ε.Ε.). Το εργαλείο που χρησιμοποιήθηκε για τη διερεύνηση είναι το Κοινό Αλιευτικό Μητρώο (Κ.Α.Μ., Community Fleet Register). Το Κ.Α.Μ. είναι μια βάση δεδομένων των εγγεγραμμένων αλιευτικών σκαφών της κάθε χώρας με στοιχεία που αφορούν τα τεχνικά χαρακτηριστικά τους (μήκος, ισχύς κινητήρα, χωρητικότητα, αλιευτικά εργαλεία) καθώς και άλλες σημαντικές πληροφορίες (έτος κατασκευής, ένταξης στο στόλο, απόσυρσης κ.α.). Επιπλέον, αποτελεί το μοναδικό κοινό και ταυτόχρονα αξιόπιστο εργαλείο αναφοράς μεταξύ των κρατών-μελών της Ε.Ε. Οι επιμέρους στόχοι της μελέτης θα μπορούσαν να συνοψιστούν στους παρακάτω: α) η μεταβολή στο χρόνο των κλάδων της αλιείας (μικρή, μέση, υπερπόντια) και των τεχνικών χαρακτηριστικών των σκαφών που τις απαρτίζουν, β) η διερεύνηση για τη μείωση της αλιευτικής πίεσης μέσω των διαφόρων μεταρρυθμιστικών μέτρων στα οποία έχει προβεί η κοινότητα (MAGP I-IV), γ) η ύπαρξη ή όχι κοινού προτύπου μείωσης στα διάφορα κράτη-μέλη και τέλος δ) η εξέλιξη της δυναμικής του στόλου στις πιο εξαρτώμενες από την αλιεία περιοχές και οι διαφορές που αυτές παρουσιάζουν σε σχέση με το γενικό μοντέλο κάθε κράτους-μέλους στο οποίο ανήκουν. Η μελέτη αυτή είναι σημαντική λόγω της εξέχουσας θέσης που κατέχει η Ελλάδα στον Ευρωπαϊκό αλιευτικό στόλο αλλά και της ιδιομορφίας της. Είναι χαρακτηριστικό ότι το 20% περίπου των σκαφών του κοινοτικού στόλου είναι νηολογημένο στην Ελλάδα, αλλά αντιστοιχεί σε λιγότερο από το 5% της συνολικής χωρητικότητας και το 8% της ισχύος κινητήρα. Επίσης, γίνεται προσπάθεια να αναδειχθούν οι διαφορές μεταξύ χωρών και ιδιαίτερα περιοχών με διαφορετικά επίπεδα εξάρτησης από την αλιεία. Παράλληλα όμως, μπορεί να συμβάλλει στην προσπάθεια του γενικότερου πλάνου διαχείρισης της αλιείας στην Ε.Ε., μέσω των διαφόρων μεταρρυθμιστικών μέτρων για τη μείωση της αλιευτικής πίεσης με στόχο τη σταθεροποίηση και τη διατήρηση των ιχθυαποθεμάτων. / The present study has as a main goal to investigate the fishing fleet dynamics of Greece and the Member States of European Union. The tool that was used to achieve this goal was the Community Fleet Register which is a database that contains all fishing vessels of each Member State. The data for each vessel are classified in those that concern technical characteristics of the vessel (length, engine power, vessel’s gross tonnage, fishing gears) and other types of data (construction year, commission year , decommission year). Furthermore, Community Fleet Register is the only common and accurate tool that can serve as reference database for vessels characteristics among the member states of E.U. the objectives of this study can be summarized into these: a) the change through time of the fishing fleet segments (small scale fishery, industrial fishery, b) the investigation about the reduction of fishing effort through the structural policies of E.U. from the start of Common Fisheries Policy, c) the presence or not of a common reduction profile among the Member States and d) the fleet dynamics of E.U. fisheries most dependent areas with the differences that may be appeared from the general model of each Member State they belong. The importance of this study consists in the leading role of Greece at Community’s. Fishing Fleet and simultaneously it’s significant structure. It is common knowledge that although approximately the 20% E.U.’ s fishing vessels are registered in Greece only 5% of total tonnage and 8% of total engine power are entitled in Greek fishing vessels. At the same time there is an effort to come up with the differences between the Member States with different fisheries dependence level. Ultimately, this study tries to contribute to the efforts of a holistic E.U. fisheries management, throughout the policies for the reduction of fishing effort, aiming to a sustainable and viable fisheries sector.
53

Lietuvos lengvųjų automobilių parko atnaujinimo politika: ekologinis požiūris / Renewal policy for Lithuanian car fleet: ecological approach

Vipartas, Tadas 25 June 2013 (has links)
Magistro baigiamajame darbe išanalizuota Lietuvos lengvųjų automobilių parko atnaujinimo politika ekologiniu požiūriu. Iškeltos Lietuvos lengvųjų automobilių parko atnaujinimo problemos bei pateikti pasiūlymai kaip šias problemas spręsti. Teorinėje dalyje teoriniu aspektu tiriamas lengvųjų automobilių parko atnaujinimo reikalingumas, apžvelgiant mokslinę literatūrą, nagrinėjami Europos Sąjungos ir Lietuvos teisės aktai, reglamentuojantys aplinkosauginių programų transporto srityje įgyvendinimą. Išanalizuoti svarbiausi su šiuo transporto sektoriumi susiję duomenys bei įvertinta lengvųjų automobilių parko atnaujinimo ekologiniu požiūriu situacija Lietuvoje, lyginant ją su ES šalimis. Trečioje dalyje atliekama statistinė duomenų ir lyginamoji situacijos analizė, nagrinėjamas ekspertų požiūris apie Lietuvos ir ES šalių lengvųjų automobilių parko atnaujinimo politiką. / In the Master’s Thesis, there is analyzed the renewal policy for Lithuanian car fleet under ecological approach. There are set renewal issues of Lithuanian car fleet and delivered proposals for the solution of the following issues. In the theoretical part under theoretical aspect there is researched the renewal necessity for the car fleet through the review of scientific literature and legal acts of the European Union and Lithuania, which regulate the implementation of environmental protection programmes in the field of transport. There are analyzed the most significant data related to the following transport sector and assessed the renewal situation of the car fleet in Lithuania under ecological approach and its comparison with the EU countries. In the third part there is carried out statistical analysis of data and comparative analysis of the situation, and analyzed experts’ approach towards the renewal policy of the car fleet in Lithuania and the EU countries.
54

An investigation into how work-related road safety can be enhanced

Banks, Tamara Dee January 2008 (has links)
Despite the facts that vehicle incidents continue to be the most common mechanism for Australian compensated fatalities and that employers have statutory obligations to provide safe workplaces, very few organisations are proactively and comprehensively managing their work-related road risks. Unfortunately, limited guidance is provided in the existing literature to assist practitioners in managing work-related road risks. The current research addresses this gap in the literature. To explore how work-related road safety can be enhanced, three studies were conducted. Study one explored the effectiveness of a range of risk management initiatives and whether comprehensive risk management practices were associated with safety outcomes. Study two explored barriers to, and facilitators for, accepting risk management initiatives. Study three explored the influence of organisational factors on road safety outcomes to identify optimal work environments for managing road risks. To maximise the research sample and increase generalisability, the studies were designed to allow data collection to be conducted simultaneously drawing upon the same sample obtained from four Australian organisations. Data was collected via four methods. A structured document review of published articles was conducted to identify what outcomes have been observed in previously investigated work-related road safety initiatives. The documents reviewed collectively assessed the effectiveness of 19 work-related road safety initiatives. Audits of organisational practices and process operating within the four researched organisations were conducted to identify whether organisations with comprehensive work-related road risk management practices and processes have better safety outcomes than organisations with limited risk management practices and processes. Interviews were conducted with a sample of 24 participants, comprising 16 employees and eight managers. The interviews were conducted to identify what barriers and facilitators within organisations are involved in implementing work-related road safety initiatives and whether differences in fleet safety climate, stage of change and safety ownership relate to work-related road safety outcomes. Finally, questionnaires were administered to a sample of 679 participants. The questionnaires were conducted to identify which initiatives are perceived by employees to be effective in managing work-related road risks and whether differences in fleet safety climate, stage of change and safety ownership relate to work-related road safety outcomes. Seven research questions were addressed in the current research project. The key findings with respect to each of the research questions are presented below. Research question one: What outcomes have been observed in previously investigated work-related road safety initiatives? The structured document review indicated that initiatives found to be positively associated with occupational road safety both during and after the intervention period included: a pay rise; driver training; group discussions; enlisting employees as community road safety change agents; safety reminders; and group and individual rewards. Research question two: Which initiatives are perceived by employees to be effective in managing work-related road risks? Questionnaire findings revealed that employees believed occupational road risks could best be managed through making vehicle safety features standard, providing practical driver skills training and through investigating serious vehicle incidents. In comparison, employees believed initiatives including signing a promise card commitment to drive safely, advertising the organisation’s phone number on vehicles and consideration of driving competency in staff selection process would have limited effectiveness in managing occupational road safety. Research question three: Do organisations with comprehensive work-related road risk management practices and processes have better safety outcomes than organisations with limited risk management practices and processes? The audit identified a difference among the organisations in their management of work-related road risks. Comprehensive risk management practices were associated with employees engaging in overall safer driving behaviours, committing less driving errors, and experiencing less fatigue and distraction issues when driving. Given that only four organisations participated in this research, these findings should only be considered as preliminary. Further research should be conducted to explore the relationship between comprehensiveness of risk management practices and road safety outcomes with a larger sample of organisations. Research question four: What barriers and facilitators within organisations are involved in implementing work-related road safety initiatives? The interviews identified that employees perceived six organisational characteristics as potential barriers to implementing work-related road safety initiatives. These included: prioritisation of production over safety; complacency towards work-related road risks; insufficient resources; diversity; limited employee input in safety decisions; and a perception that road safety initiatives were an unnecessary burden. In comparison, employees perceived three organisational characteristics as potential facilitators to implementing work-related road safety initiatives. These included: management commitment; the presence of existing systems that could support the implementation of initiatives; and supportive relationships. Research question five: Do differences in fleet safety climate relate to work-related road safety outcomes? The interviews and questionnaires identified that organisational climates with high management commitment, support for managing work demands, appropriate safety rules and safety communication were associated with employees who engaged in safer driving behaviours. Regression analyses indicated that as participants’ perceptions of safety climate increased, the corresponding likelihood of them engaging in safer driving behaviours increased. Fleet safety climate was perceived to influence road safety outcomes through several avenues. Some of these included: the allocation of sufficient resources to manage occupational road risks; fostering a supportive environment of mutual responsibility; resolving safety issues openly and fairly; clearly communicating to employees that safety is the top priority; and developing appropriate work-related road safety policies and procedures. Research question six: Do differences in stage of change relate to work-related road safety outcomes? The interviews and questionnaires identified that participants’ perceptions of initiative effectiveness were found to vary with respect to their individual stage of readiness, with stage-matched initiatives being perceived most effective. In regards to safety outcomes, regression analyses identified that as participants’ progress through the stages of change, the corresponding likelihood of them being involved in vehicle crashes decreases. Research question seven: Do differences in safety ownership relate to work-related road safety outcomes? The interviews and questionnaires revealed that management of road risks is often given less attention than other areas of health and safety management in organisations. In regards to safety outcomes, regression analyses identified that perceived authority and perceived shared ownership both emerged as significant independent predictors of self-reported driving behaviours pertaining to fatigue and distractions. The regression models indicated that as participants’ perceptions of the authority of the person managing road risks increases, and perceptions of shared ownership of safety tasks increases, the corresponding likelihood of them engaging in driving while fatigued or multitasking while driving decreases. Based on the findings from the current research, the author makes several recommendations to assist practitioners in developing proactive and comprehensive approaches to managing occupational road risks. The author also suggests several avenues for future research in the area of work-related road safety.
55

Terceirização da gestão de frotas leves corporativas no Brasil: identificação de variáveis entre 'ter' ou 'terceirizar' na gestão de frotas leves

Zini, David Martins 19 March 2018 (has links)
Submitted by David Martins Zini (zinibr@yahoo.com.br) on 2018-03-27T01:24:26Z No. of bitstreams: 1 Dissertação MPA_David Zini_Final.pdf: 2374573 bytes, checksum: 1c3b3306314290573dd52a0997d9bc07 (MD5) / Approved for entry into archive by Mayara Costa de Sousa (mayara.sousa@fgv.br) on 2018-03-28T18:28:10Z (GMT) No. of bitstreams: 1 Dissertação MPA_David Zini_Final.pdf: 2374573 bytes, checksum: 1c3b3306314290573dd52a0997d9bc07 (MD5) / Approved for entry into archive by Suzane Guimarães (suzane.guimaraes@fgv.br) on 2018-04-02T13:31:45Z (GMT) No. of bitstreams: 1 Dissertação MPA_David Zini_Final.pdf: 2374573 bytes, checksum: 1c3b3306314290573dd52a0997d9bc07 (MD5) / Made available in DSpace on 2018-04-02T13:31:45Z (GMT). No. of bitstreams: 1 Dissertação MPA_David Zini_Final.pdf: 2374573 bytes, checksum: 1c3b3306314290573dd52a0997d9bc07 (MD5) Previous issue date: 2018-03-19 / Na Gestão de Frotas Leves Corporativas no Brasil, o que é melhor ‒ terceirizar ou gerir a própria frota? Este trabalho propôs-se a identificar as variáveis mais relevantes no processo de decisão entre 'TER' ou 'TERCEIRIZAR' quanto à necessidade que algumas das empresas privadas brasileiras possuem em dispor de uma frota de veículos leves. Entre os diversos elementos envolvidos nesta lógica decisória, poder-se-ia destacar a capacidade de auferir desempenho comparativo; a assimetria da informação e o conhecimento sobre os custos reais da empresa. Neste estudo, pretendeu-se compreender o processo de tomada de decisão aplicado especificamente à Gestão da Frota de Veículos Leves das empresas privadas nacionais. Inclui-se neste conceito de Gestão de Frotas Leves, os veículos, as manutenções, a documentação e o monitoramento. Inicialmente, optou-se por analisar dados secundários referenciando a literatura sobre a teoria da firma, definição de fronteiras verticais, mercados competitivos, indústrias com baixo poder de barganha frente aos compradores e dificuldades para substituir produtos e soluções tradicionais. Na sequência, formatou-se uma pesquisa pelo método quantitativo-descritivo, sobre uma base de Gestores de Frotas Leves do Brasil, para identificarem-se os fatores mais relevantes na tomada de decisão entre terceirizar ou verticalizar este serviço. Finalmente, foram individualizados os aspectos mais relevantes nesta tomada de decisão empresarial e de que maneira eles seriam 'as variáveis' para preferência entre os modelos de contratação, bem como se propôs um modelo com nova abordagem ao mercado que, acredita-se, poderá desenvolver-se. / In the corporate light fleet management in Brazil context, what's the best choice, outsourcing or in-house management? The purpose of this study understands those more relevant variables on decision making process between 'buy' or 'make' regarding of Brazilian's private companies, which are demanding for light fleet vehicles. Among the different factor involved on this logical think we could highlight, capacity for major comparative performance, information asymmetric and well know of real firm's costs. This study intends to understand the decision-making process in Light Fleet Management on Brazilian private companies, which are included vehicles, maintenances, documentations handling, and controls. On the beginning, we are analyzing primary data from lecture on the classical theory of the firm, defining vertical frontiers of the firm, industries with low bargain power against buyers and difficulties for replacement traditional solutions. On the sequence, we do format a described - quantitative method of searching on the Brazilian Fleet Management base for identify the key factors on the decision-making process between outsourcing or in-house solution. Finally, we could identify more representative aspects of this managerial decision and how the 'variables' of preferences has been influenced those different contract models and proposed a new market approach with intention of leverage this industry.
56

Způsoby pořizování dopravních letadel a fleet management letecké společnosti / Airline Fleet Management and Airliner Acquisition Methods

Greguš, Adam January 2017 (has links)
The aim of this thesis is to work out a topic regarding airliner acquisition and financing methods. Fleet planning is an important decision-making process because acquiring an aircraft is a capital-intensive investment. There are different methods of acquiring and financing and each of them have its advantages and disadvantages which complies different operational, tactical and strategical needs of an airline. The aim is also to analyze and describe current and forecast situation within the airline industry both globally and regionally. The last part is dedicated to flight fleet management instruments, such as performance, operational, financial metrics and indicators that helps an airline to operate its fleet efficiently, and a case study based upon a real ACMI contract.
57

Developing an optimization model to determine AGV fleet size given the capacity of machines and vehicles in the production industry

Zaher, Milad, El Ghazzi, Ale January 2021 (has links)
Background: In the present competitive environment manufacturing firms have shifted their production from mass production to mass customization. In this line, a flexible manufacturing system (or FMS) has evolved to the changing requirements. The estimation of fleet size of AGVs has shown to be a critical decision to increase the efficiency of material handling systems by increasing throughput and reduce delay in manufacturing.[4] The initial investment cost and the total life cycle cost of AGV systems rely on the number of AGVs required.   Objectives: The objective of this study is to analyze the optimal fleet sizing of AGVs in terms of the capacity needs of machines/stations and the available capacity of the AGVs working in the production site. The aim of this study is to give potential users of AGVs an optimization model to consider when planning the optimal number of AGVs needed given their capacity needs.   Methods: The methodology presents our contribution to a general model for deciding fleet size with multiple AGV’s defined as a “big system”. In comparison to previous models, we consider how the capacity of AGV’s can change depending on several factors leading to congestion and delay. The study defines these factors, finds the cause behind them and categorizes them to be used as input variables for the model. The methodology explains the important factors needed for implementing the general model for specific cases when conducting the investigation. The final part of the methodology will discuss the reliability and validity of our approach.  Results: the result presents how the general model was applied at the manufacturing company of Emballator Växjöplast AB. The data gathered and information from the capacity analysis were used to measure the demand for transportation, the AGV capacity, and the factors affecting delay and congestion. The values were then used in the model to determine the optimal fleet size for the case. The result gave a high indication for accuracy and that the general model can be used in specific cases. Finally, we conducted an analysis of how delays and congestion affected the supply of transportation as fleet size increases. The result indicated that the optimal fleet size of AGVs that satisfy 35 machines/stations was 1,32 while the theoretical fleet size of AGVs was 1.3. This yielded a result of 98.84% accuracy in estimating the optimal fleet sizing of AGVs in terms of the capacity needs of machines/stations and the available capacity of the AGVs working in the production site. Conclusions: The result shows that the approach of analyzing the capacity needs of the production site and the capacity available to the AGV can accurately be used to estimate the optimal fleet sizing of AGVs. The implication of this study and the optimization model that considers capacity needs and capacity available rather than specific layout characteristics will allow users to cope with the changing requirements of mass customization. The users will consider their demand forecast and use the optimization model to help them plan the optimal fleet sizing of AGVs. / Bakgrund: I den nuvarande konkurrensenskraftiga miljön har tillverkningsföretag skiftat produktion från massproduktion till massanpassning. Därmed har flexible manufacturing system (eller FMS) växt fram till följd av de förändrade kraven. Estimation av fleet size av AGV har visat sig vara ett kritiskt beslut för att öka effektiviteten av materialhanteringssystem genom ökad genomströmning och minskad försening i produktionen.[4] Den initiala investeringskostnaden och den totala livscykelkostnaden beror på antalet AGVer som det finns behov av i produktionen.   Syfte: Syftet med här studien är att analysera det optimala antalet AGVer som det finns behov av i relation till kapacitetsbehovet hos maskiner/stationer och den tillgängliga kapaciteten hos AGV som arbetar i produktionsanläggningen. Målet med den här studien är att förse potentiella användare av AGV med en optimeringsmodell som de kan använda vid planering av antalet AGV som de har behov av givet deras kapacitetsbehov.   Metod: I metoden presenteras vårt bidrag till en generell modell för att bestämma antalet AGV: er för ett system med flera enheter som definieras som ett ”stort system”. Till skillnad från tidigare modeller, så tar vi hänsyn till flera faktorer som orsakar kongestion och fördröjningar. Studien definierar dessa faktorer, finner orsaken till dem, och kategoriserar dem för att kunna tillämpa dem i modellen. Metoden förklarar vikten av varför dess variabler är nödvändiga att mäta när den generella modellen tillämpas för specifika fall när man utför en utredning av fallet. Slutligen avslutas metoden med att diskutera dess trovärdighet och validitet.     Resultat: Resultatet presenterar hur den generella modellen tillämpats på ett produktionsföretag Emballator Växjöplast AB.  Datainsamlingen och information från kapacitet analysen har använts för att mäta transportbehovet, AGV: ens kapacitet och de påverkande faktorer som orsakar fördröjning och kongestion. Dessa värden användes sedan i den generella modellen för att avgöra det optimala antalet AGV: er för fallet. Resultatet indikerar tydligt på att det finns en hög precision av den generella modellen kan tillämpas för specifika fall. Slutligen utför vi en analys om hur fördröjningar och kongestion påverkar transportillförsen i samband med att antalet AGV: er ökar. Resultatet visar att det optimala antalet AGVer som det finns behov av för att förse kapacitetsbehovet av 35 maskiner/stationer var 1.32 medan det teoretiska svaret från optimeringsmodellen visade ett svar på 1.30 AGVer. Detta resulterade i en noggrannhet på 98.84% för att estimera antalet AGVer som det finns behov av givet kapacitetsbehovet från maskiner/stationer och den tillgängliga kapaciteten hos AGVerna som jobbar på produktionsanläggningen.   Slutsatser:  Resultatet av tillvägagångssättet som använts i denna studie, att analysera kapacitetsbehovet i produktionsanläggningen och den tillgängliga kapaciteten hos AGVerna, visade sig vara noggrann för att estimera det optimala behovet av AGVer. Detta innebär att optimeringsmodellen som presenteras i denna studie och som tar hänsyn till kapacitetbehovet snarare än de specifika layoutegenskaperna kommer göra det möjligt för användarna att kunna uppfylla de förändrade kraven på massanpassning. Användaren kommer kunna använda sin prognos på efterfrågan och i samspel med användning av optimeringsmodellen presenterad i denna studie kunna estimera det optimala antalet AGVer som det finns behov av.
58

Development and Assessment of Re-Fleet Assignment Model under Environmental Considerations / Utveckling och bedömning av metoder för allokering av flygplanstyper till rutter med hänsyn till miljöaspekter

Prashant, Prashant January 2020 (has links)
The imminent threat of global catastrophe due to climate change gets more real by each passing year. The Aviation trade association, IATA, claims that Aviation accounts for approximately 2% of the Greenhouse Gases (GHG) caused by human activities, and 3.5% of the total Radiative Forcing. With continuous increase in Aviation industry and subsequent drop in fossil fuel prices, these numbers are only expected to up with time. In Addition, these numbers do not include the effects of altitude of emission and many environmentalists believe that the number for some pollutants could be at least 2-3 times larger than IATA estimates. This rising concern engages the Aviation industry to investigate possible methods to alleviate their environmental impact.  The first part of this thesis provides a framework to support Airlines in monitoring their current environmental footprint during the process of scheduling. This objective is realised by developing a robust system for estimating the fuel consumed (ergo quantity of major Greenhouse Gases emitted) by a particular fleet type operating a certain leg, which is then employed in a Fleet Assignment (FA) Operation to reduce emissions and increase the Contribution. An emissions estimation model for Turbojet Aeroplane fleets is created for Industrial Optimizers AB’sMP2 software. The emissions estimation model uses historic fuel consumption data provided by ICAO for a given fleet type to estimate the quantity (in kg) of environmental pollutants during the Landing and Takeoff operation (below 3000 ft) and the Cruise, Climb and Descent operation (above 3000 ft).  The second part of this thesis concerns with assigning monetary weights to the pollutant estimates to calculate an emission cost. This emission cost is then added to MP2’s Fleet Assignment’s objective function as an additional Operational cost to perform a Contribution maximization optimization subjected to the legality constraints. The effects of these monetary weights levied on the results of Fleet Assignment are studied, and utilizing curve-fitting and mathematical optimization, monetary weights are estimated for the desired reduction in GHG emissions.  Finally, a recursive algorithm based on Newton-Raphson method is designed and tested for calculating pollutant weights for untested schedules. / Det omedelbara hotet om en global katastrof pga klimatförändringar blir mer och mer tydligt för varje år som går. IATA, den internationella flyghandelsorganisationen, hävdar att flyget står för runt 2% av växthusgaserna (GHG) som kommer från människans aktiviteter, och 3.5% av den totala avstrålningen. Med den kontinuerliga tillväxten av flygindustrin och prisminskningar av fossila bränslen så förväntas dessa andelar att öka. Dessutom så inkluderar inte dessa siffror effekten av att utsläppen sker på hög höjd, och många miljöaktivister tror att siffrorna för vissa utsläpp kan vara åtminstone 2-3 gånger högre än IATAs uppskattningar. Denna växande oro motiverar flygindustrin till att undersöka metoder för att begränsa dess miljöpåverkan.  Den första delen av denna rapport ger ett ramverk för att hjälpa flygbolag med att bevaka deras aktuella miljöavtryck under schemaläggningsprocessen. Detta mål realiseras genom att utveckla ett robust system för att uppskatta bränsleförbrukningen (och därmed kvantiteten av växthusgasutsläpp) av en specifik flygplanstyp på en given etapp, som sedan kan användas för att allokera flygplanstyper för att minska utsläppen och bidra till att förbättra miljön. En modell för att uppskatta utsläpp för flottor av turbojetflygplan har skapats för Industrial Optimizers AB programvara MP2. Modellen för att uppskatta utsläppen baseras på historiska data om bränsleförbrukning som tillhandahållits av ICAO för en given flygplanstyp som använts för att uppskatta kvantiteten (i kg) av föroreningar vid start (under 3000 fot) och vid sträckflygning, stigning och inflygning (över 3000 fot). Den andra delen av denna rapport handlar om att bestämma monetära vikter till föroreningsskattningarna för att beräkna utsläppskostnader som ska användas i MP2 s målfunktion för allokering av flygplanstyper. Detta ger en ytterligare driftskostnad att beakta i optimeringen för att få med miljöaspekterna och tillåtna lösningar. Effekten som dessa monetära vikter har på resultaten från optimeringen studeras, och genom att använda kurvanpassning och matematisk optimering, de monetära vikterna anpassas för att få den önskade minskningen i växthusgasutsläpp. Slutligen så har en rekursiv algoritm, baserad på Newon-Raphsons metod, designats och testats för att beräkna utsläppsvikter för scheman som inte använts för att beräkna vikterna
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Studies in Airline and Aviation Efficiency

Park, Yongha 10 August 2017 (has links)
No description available.
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Moving beyond connecting things : What are the factors telecommunication service providers need to consider when developing a Data-as-a-Service offering? / Steget vidare från uppkoppling av produkter: : Vilka faktorer bör IoT-operatörer ta hänsyn till vid utveckling av Data-as-a-Service tjänster?

GOHARI MOGHADAM, SHERVIN, ÅHLGREN, THOR January 2020 (has links)
The Internet of Things and connected devices has been getting more and more recognition in multiple industries the last few years. At the same time, the gathering of data is withholding a more central role for both companies and civilians. One type of Internet of Things is enabled by telecommunication Service Providers(TSP)providing SIMcards in devices, functioning by an advanced telecommunication infrastructure. This study aims to examine how these TSPs can leverage data generated by the communication infrastructure, by providing an additional data-as-a-service (DaaS) to current customers. The study was done at a global TSP within the area of SIM-fleet management/IoT enablement. The number of industries that are starting to connect devices are growing extensively, to get all types of information regarding the devices ranging from electricity-usage & geocoordinates to performance or other useful information. The data that is sent by the SIM-card belongs to the customer, and the TSPs does not access it. However, the telecommunication infrastructure generates data created by the communication of the devices, which is gathered by the TSP. Since a huge amount of data is attained by the TSP offering the infrastructure, the aim for this study is to examine eventual obstacles and opportunities of a DaaSoffering. How the data is to be delivered, customers connectivity-needs and how current insights streams are delivered are examples of subjects the study will examine. The work has its foundation in a theoretical reference frame and a qualitative empirical study. The theoretical reference provides a theoretical overview of the industry's development and earlier research within the area. It was created by conducting a literature study combined with reports provided by trade organizations and other stakeholders. The empirical study contains 6 interviews with employees at a global TSP, with an extensive history of connected devices. The two parts were then compiled in order to compare the result with the theoretical background. It appeared that a lot of the challenges of developing a DaaS from the result agreed with the theoretical reference frame. The customers' differences in connectivity-maturity was shown to pose a great challenge to standardize a DaaS-offering, and the clients analytical needs were dependent on the same premises. Furthermore DaaS is considered to have a great effect on the industry's future development, / Internet of Things och uppkopplade produkter har blivit ett allt vanligare begrepp inom flertalet branscher. Samtidigt har datainsamling blivit en mer central del av alltifrån affärsmodeller till något vanliga konsumenter har i åtanke. En variant av Internet of Things tillhandahålls genom SIM-kort i produkter, som tillhandahålls av operatörer, och funktionerar genom kommunikationsnätverk. Denna studie är en akademisk utredning kring hur dessa operatörer kan utnyttja data genererat från telekommunikations-infrastruktur till en tjänst för nuvarande kunder. Studien är utförd hos en global operatör inom området av SIM-fleet Management/IoT-enablement. Fler och fler industrier går mot att koppla upp produkter för att få information kring alltifrån prestanda, elanvändning hos produkten, geografisk position eller annan information som önskas. Den data som skickas tillhandahålls av kund, vilket operatören inte har någon tillgång till. Dock så genererar kommunikationen i sig data genom kommunikationsnätverket, som operatören samlar in. I och med att mängder av data blir tillgänglig för operatörerna som tillhandahåller infrastrukturen, är syftet med denna rapport att undersöka eventuella hinder och möjligheter att erbjuda kunder ytterligare data som en tjänst i sig. Hur datan ska levereras, kundernas analysbehov och hur nuvarande insikter levereras är några exempel på det studien utreder. Arbetet grundar sig i en litteraturstudie och en kvalitativ empirisk studie. Litteraturstudien ger en bakgrund och teoretisk överblick kring branschens utveckling och litteraturens syn på området. Detta gjordes genom vetenskapliga publikationer samt diverse rapporter från branschorganisationer och intressenter. Den empiriska studien genomfördes genom 6 intervjuer med anställda på en global operatör med lång historisk inom uppkopplade produkter. De två delarna sammanställdes sedan för att jämföra resultatet med den teoretiska bakgrunden. Det visades sig vara mycket i resultat som stämde överens med de teoretiska aspekterna kring utmaningar med att erbjuda Data-as-aService (DaaS). Kundernas olika mognadsgrad i sin uppkoppling visades sig vara en stor utmaning i att standardisera en DaaS, och kundernas analysbehov gick ofta isär på samma premisser. Vidare anses DaaS ha stor påverkan på hur branschen fortsätter utvecklas i framtiden, och konsensus är tjänsten i framtiden kommer bli mer och mer datadriven.

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