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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.
591

Energitjänst för efterfrågeflexibilitet : Som leder till en effektivare elnätsanvändning / Energy service for demand-side flexibility : Resulting in a more efficient use of the electrical grid

Nilsson, Martin, Samuelsson, Simon January 2015 (has links)
The load in the electricity grid fluctuates during the day and between seasons. As a distribution system operator (DSO), an uneven load profile leads to increased transmission losses and unnecessary high costs for subscribing power from the feeding grid. Efficiency measures and a more even power consumption by the end-users, could therefore lead to that a DSO can achieve lower costs for power-subscription from the feeding grid and transmission losses, but also implies a lowered cap of total revenues. As a step towards implementing the EU energy efficiency directive, the Energy Markets Inspectorate (Ei) have developed two economic incentives which enables for DSOs to profit economically from cost reductions related to transmission losses and feeding grid. For this reason the electricity suppliers Storuman Energi and Affärsverken Energi sees a possibility to offer a load shift-service to low voltage DSOs using the flexibility in the demand of electrically heated households. The aim of this study is therefore to demonstrate how a service such as this one can be valued in the Swedish electricity market. The task at hand was examined by conducting a survey of the values of demand-side flexibility, as well as an investigation of how the costs for the end-user and incentives for the DSO are affected by flexibility. A review of the values associated with demand-side flexibility has been conducted for electricity suppliers, DSOs and end-users. With regard to the DSOs, the main value is connected to the new economic incentives from Ei, whose potential depends on the properties of the grid and the tariff for the feeding grid. Other values related to operation and delivery reliability can also be achieved. The main values for electricity suppliers are a lowered risk for unbalance following as a consequence of better knowledge of their end-users’ usage, and also the possibility to profit by offering a load shift-service. The values for end-users have been divided between cost reductions and system benefits, both of which are regarded to compensate the remuneration end-users require to offer their flexibility. By adapting consumption after the spot market price or the grid tariff, lowered costs for electricity can be achieved. The end-users can also appreciate system-benefits such as the facilitation for intermittent renewable electricity production, electric vehicles and reducing the societal dependency on expensive fossil-fuelled power generation as positive. They do on the other hand regard a possible depreciation of the heat comfort, data confidentiality and reduced control over one’s own electricity consumption as negative. If the service can be bundled with equipment which yields other values, such as an increased heat comfort, the end-users’ demand for remuneration can decrease. To explore what effects demand-side flexibility can have on the electricity costs of end-users and the economic incentives for DSOs, a case study is conducted in the electricity distribution grid of Karlskrona. Through review of previous studies, a potential for demand reductions was established and used as input in the case study. It can be determined that the incentive for a more even load profile constitutes a substantially greater share of the total incentives, compared to the incentive for reduced distribution losses. It is further concluded that a fairly large part of the incentives can be achieved by controlling the end-users on only a few occasions each year. It is also established that the cost reductions for end-users can match their demand for remuneration. A future scenario with more electrical vehicles connected to the grid for charging, greatly increases the possible benefits for both the DSO and end-users. Through the investigation of different possible designs for the energy service, it is recommended that the demand side management of end-users is placed in the hands of an electricity supplier responsible for balancing the consumption of the end-users. A procurement-procedure is deemed problematicfollowing the risk for unproportional use of resources and time. As a result of this, the energy service should not be traded directly between DSOs and electricity suppliers. Instead, it is proposed that the DSO develops a time-differentiated tariff, after which the electricity supplier can adapt the end-users’ consumption. Since the results indicate that controlling the end-users consumption on just a few occasions is sufficient to yield large benefits for the DSO, a grid-tariff with critical peak pricing is recommended. This tariff employs a high price for shorter periods of time when the grid load is peaking and a rebated price during all other occasions. This opens up for controlling the use during the other days according to the spot market price. As the electricity supplier grants the end-user lowered costs for both the electricity grid and trading, they have the opportunity to apply a charge for the service. Both the DSO, end-user and electricity supplier is presumed to improve their profitability with this design. When implementing the energy service, a couple of aspects are important to shed light on. The grid-tariff of the end-user and the tariff for the feeding grid needs to be synchronized with each other, to stimulate the same type of load shifts. It should also be noted that the possible gain from the incentives will decrease as demand side management-measures is taken since the reference-level from which a comparison is made improves. Another interesting aspect is that the regulation stipulates that only a certain percentage of the cost reductions will result in incentives, thus limiting the amount of profitable measures. Since the costs and revenues between the actors in the transmission system (low and medium voltage DSOs and the TSO) are interdependent, the revenue loss for the medium voltage DSO resulting from the cost reduction for the low voltage DSO, can result in a recoil effect. Lastly, a widespread introduction of control equipment to end-users can facilitate other uses for the demand-side flexibility. / Belastningen i elnätet varierar under dagen och mellan olika säsonger. Att som nätägare ha en ojämn belastning i sitt nät leder till ökade nätförluster och onödigt höga kostnader för att abonnera effekt från det överliggande nätet. Effektiviseringar i nätet och ett jämnare effektuttag av användarna kan därmed leda till att en nätägare kan erhålla minskade kostnader för abonnerad effekt från överliggande nät och nätförluster, men innebär också en sänkt intäktsram för nätägaren. Vid implementering av EU:s energieffektiviseringsdirektiv har Energimarknadsinspektionen tagit fram två ekonomiska incitament som möjliggör för nätägare att dra nytta av kostnadsminskningar för nätförluster och överliggande nät. Av denna anledning ser elhandelsbolagen Storuman Energi och Affärsverken Energi möjligheter att, med hjälp av efterfrågeflexibilitet hos framförallt eluppvärmda hushåll, erbjuda en laststyrningstjänst till lokalnätsnätägare. Syftet med denna studie är därmed att demonstrera hur en tjänst som denna kan värdesättas av aktörerna på den svenska elmarknaden. Frågan behandlas genom att undersöka vilka värden efterfrågeflexibilitet kan ge upphov till, exempelvis hur slutanvändares elkostnader och nätägares ekonomiska incitament påverkas av efterfrågeflexibilitet. En inventering har gjorts av efterfrågeflexibilitetens värde för elhandlare, nätägare och slutanvändare. För nätägare bedöms de huvudsakliga värdena finnas kring de nya ekonomiska incitamenten, vars potential beror på nätets förutsättningar och regionnätstariffen. Det finns också nyttor kopplade till driftsäkerhet och leveranskvalitet. Elhandlare kan dra nytta av en lägre risk för obalans genom att de får bättre uppfattning om sina kunders användningsmönster, samt möjligheten att även debitera för utförd laststyrningstjänst. För slutanvändare har värdena delats upp i kostnadsminskningar och systemnyttor. Båda dessa anses kunna kompensera för de krav på ersättning som slutanvändare har för att bidra med sin flexibilitet. Genom anpassning efter exempelvis spotpris eller en nättariff kan lägre kostnader för elhandel respektive nät erhållas. Vad gäller systemnyttor kan följder som att exempelvis främja intermittent förnybar elproduktion, underlätta införande av en eldriven fordonsflotta samt att minska beroendet av dyra fossileldade produktionsslag ses som positiva. Å andra sidan bedöms en upplevd risk för försämrad värmekomfort och datasekretess samt minskad kontroll över sin användning spela in som negativa värden. Om tjänsten kan paketeras tillsammans med utrustning som även ger andra mervärden, exempelvis möjliggör en ökad värmekomfort, kan slutanvändares ersättningskrav minska. För att utreda vilken konkret påverkan efterfrågeflexibilitet kan ha på slutanvändares elkostnader och nätägares ekonomiska incitament görs en undersökning i Karlskronas lokalnät. Där appliceras den potential för efterfrågeflexibilitet som tidigare studier visat på. Det konstateras att incitamentet för jämnare nätbelastning visar betydligt större potential än det för minskade nätförluster samt att en stor del av incitamenten går att erhålla genom att styra endast ett fåtal tillfällen varje år. Vidare pekar resultatet på att slutanvändares kostnadsminskningar kan nå upp i nivåer som motsvarar deras ersättningskrav. Ett framtidsscenario med fler elfordon ger mycket större ekonomisk potential för både nätägare och slutanvändare. Efter att ha utrett olika alternativa utformningar för energitjänsten föreslås att passiv efterfrågeflexibilitet tillämpas genom att laststyrning av slutanvändare sker av en elhandlande aggregator med balansansvar. Ett upphandlingsförfarande bedöms medföra risk för stor resurs- och tidsåtgång, varför handel av tjänsten inte bör äga rum mellan elhandlare och nätägare. Men för att elhandlare ändå ska kunna ta del av värdet från de ekonomiska incitamenten föreslås att nätägaren tar fram en tidsdifferentierad nättariff, vilken elhandlaren kan laststyra slutanvändare efter. Då resultatet pekar på att styrning under endast ett fåtal tillfällen är erforderligt kan en nättariff av typen spetspristariff tillämpas, där kostnaden för effektuttag kraftigt stiger när belastningen är hög i nätet. Då möjliggörs styrning efter exempelvis spotpris de tillfällen som inte är nödvändiga att styra med hänsyn till nätet, eftersom kostnaden för effektuttag då är låg. Genom att elhandlare på så sätt kan erbjuda slutanvändare lägre kostnader för både nät och elhandel har de möjlighet att debitera slutanvändare en avgift för utförd tjänst. Med denna utformning anses både nätägare, elhandlare och slutanvändare kunna nå en ökad lönsamhet. Vid införandet av energitjänsten är ett antal aspekter viktiga att belysa. Slutanvändares nättariff och lokalnätets tariff för överliggande nät spelar en viktig roll då de behöver stimulera till att samma styrning utförs, exempelvis om det är fördelaktigt att styrning sker ofta eller mer sällan. Då incitamentens nivå bestäms utifrån en referensperiod kommer möjlig avkastning att avta i takt med att förbättringar görs. I nätregleringen är det fastställt att bara en viss del av kostnadsbesparingarna erhålls i form av de ekonomiska incitamenten, vilket innebär att vilka åtgärder som är lönsamma begränsas. Genom att kostnader och intäkter är tätt sammankopplade mellan aktörerna i elnätet (lokal-, region- och stamnät) kan regionnätets intäktsbortfall till följd av lokalnätets lägre kostnader, ge upphov till rekyleffekter. Att storskaligt installera styrutrustning hos slutanvändare kan också möjliggöra andra användningsområden, med andra ord skapas det en plattform för efterfrågeflexibilitet.
592

Υλοποίηση και εξομοίωση ενός max-min fair sharing αλγορίθμου και σύγκριση αλγορίθμων χρονοπρογραμματισμού σε Grids / Implementation and simulation of fair grid scheduling algorithms

Νταφούλη, Ελένη 26 February 2009 (has links)
Θέμα της παρούσας εργασίας είναι η υλοποίηση και εξομοίωση δίκαιων αλγόριθμων χρονοπρογραμματισμού σε Grids και η σύγκρισή τους με κλασικούς αλγόριθμους χρονοπρογραμματισμού. Η βασική ιδέα πίσω από την τεχνολογία Grid και τις υπηρεσίες που παρέχει είναι η ενοποίηση υπολογιστικών και αποθηκευτικών πόρων και η συνολική θεώρηση τους από τους χρήστες. Με τον τρόπο αυτό γίνεται δυνατή η ανάπτυξη πολύπλοκων και απαιτητικών εφαρμογών, τόσο στον χώρο της επιστημονικής έρευνας, όσο και στα πλαίσια της παραγωγής εμπορικών λύσεων. Ένα τέτοιο σύστημα απαιτεί διαμοιρασμό των υπολογιστικών και άλλων πόρων καθώς και μεγάλες ταχύτητες σύνδεσης μεταξύ τους. Οι αλγόριθμοι χρονοπρογραμματισμού αναλαμβάνουν τον αποδοτικό διαμοιρασμό των πόρων ώστε να επιτυγχάνεται καλύτερη ποιότητα υπηρεσίας. Η αποτελεσματικότητα ενός αλγόριθμου χρονοπρογραμματισμού εξαρτάται από την συνάρτηση που θέλουμε να βελτιστοποιήσουμε, που με τη σειρά της εξαρτάται από τεχνο-οικονομικά κριτήρια. Στην προσπάθεια βελτιστοποίησης της εκάστοτε συνάρτησης ευνοούνται κάποιες προς εκτέλεση διεργασίες έναντι άλλων. Ένας δίκαιος αλγόριθμος χρονοπρογραμματισμού όμως θα πρέπει να συμπεριφέρεται με τον ίδιο τρόπο σε όλες τις διεργασίες ανεξαρτήτως των χαρακτηριστικών τους. Στην εργασία που θα παρουσιάσουμε, αναλύουμε δύο δίκαιους αλγόριθμους χρονοπρογραμματισμού, τον Fair Completion Time (Ordering) και τον Fair Completion Time Estimation (Assignment). Κατόπιν τους υλοποιούμε και τους εξομοιώνουμε με το GridSim Toolkit και συγκρίνουμε την απόδοση τους με κλασικούς αλγόριθμους χρονοπρογραμματισμού. / The subject of this thesis is the implementation and simulation of fair scheduling algorithms applied on Computational Grids and their comparison with the classic scheduling algorithms. The basic idea of the Grid Technology and the services it provides, is the unification of computational and storage resources. This way it is possible to serve sophisticated applications, in fields like scientific research and trading. A Grid Network demands the sharing of the computational and storage resources, and high bandwidth connections between them. Scheduling algorithms are responsible for the efficient assignment of tasks to resources for better quality of service. Evaluating the efficiency of a scheduling algorithm depends on a utility function that we seek to optimize which in turns depends on techno-economic criteria. As a result of trying to optimize the utility function, some tasks with specific characteristics are favoured against others. A fair scheduling algorithm however should treat all tasks in the same way regardless of their characteristics. In this thesis we study the Fair Completion Time Ordering Algorithm and suggest a new fair scheduling algorithm called Fair Completion Time Estimation Assignment Algorithm. We implement and simulate these algorithms using the GridSim Toolkit and compare them with the classic scheduling algorithms.
593

Ledarskap och frisknärvaro : en kvalitativ intervjustudie

Axewill, Frederick January 2014 (has links)
Frågan om chefers ledarskaps påverkan på de anställdas hälsa har aktualiserats under senare tid. Dock finns inte mycket forskning på området, vilket gör att denna uppsats kan komma att fylla en funktion i detta sammanhang. Uppsatsen har som syfte att ta reda på hur förskolechefer i en svensk kommun utövar sitt ledarskap och om det går att se någon koppling till medarbetarnas frisknärvaro. Med hjälp av kvalitativ metod där fem semistrukturerade intervjuer genomfördes besvaras följande frågor i kandidatuppsatsen:   Vilket slags ledarskap utövar förskolecheferna? Vilka likheter finns i ledarskapsstilarna mellan de förskolechefer som har hög frisknärvaro bland medarbetarna? Skiljer sig ledarskapet åt, i så fall hur, mellan de chefer som har hög frisknärvaro och de med mellanhög och låg dito?   Min slutsats är att det finns likheter i hur cheferna utövar sitt ledarskap. Alla fem har starkt fokus på produktionsorienterat ledarskap, medan det skiljer en hel del mellan dem när det gäller det relationsorienterade dito. Tre av fem utövar mer eller mindre det salutogena ledarskapet. Den chef som har lägst frisknärvaro är den som leder på ett mest produktionsorienterat sätt. Resultatet av denna studie tyder på att ledarskap, för att öka frisknärvaron, bör utövas med tydlighet, närvaro och delaktighet. / The issue of managers' leadership influence on the health of employees has been actualized recently. However, there is a lack of research in this area, which motivates a focus on this topic. This study aims to find out how pre-school managers in a Swedish municipality exercises leadership and if you can see any connection to the staff's work attendance. By using the qualitative method in which five semi-structured interviews were conducted, I have got some answers to the following questions in this study:     1. What kind of leadership does preschool heads exercise? 2. What similarities are there in leadership styles between the  pre-school managers who have high work-attendance among staff? 3. Is there a difference in the leadership between the managers who have high work attendance and those with medium- and low ditto? If so what differs between them?   My conclusion is that there are similarities in how managers exercise their leadership. All five have a strong focus on production oriented leadership, while it differs more between them when it comes to the relationship oriented one. Three of the five exercise more or less the salutogenic leadership. The manager with staff with the lowest work attendance is the one who exercise her leadership in the most production-oriented way. Results from this study indicate that leadership, to increase work attendance, should be exercised with clarity, presence and inclusion.
594

Interaktyvių e – mokymo sistemų pritaikymas paslaugoms orientuotai Grid architektūrai / Interactive e-learning system adaptation for service oriented Grid architecture

Jukniūtė, Aistė 16 August 2007 (has links)
Daugėjant informacijos ir paslaugų kiekiui internete tradicinės elektroninio mokymo architektūros vis sunkiau patenkina iškylančius integracijos, išplėtimo, resursų valdymo poreikius. Nauja paslaugom orientuota architektūra, įgyvendinama žiniatinklio paslaugų technologijomis bei Grid aplinka yra tinkamas būdas efektyviam ir kokybiškam e-mokymui užtikrinti. Šiame darbe nagrinėjama kokias naujas galimybes e-mokymo srityje atveria paslaugom orientuota Grid architektūra. Tam kad būtų galima pasinaudoti naujomis galimybėmis turimą sistemą reikia modifikuoti. Pateikiamos rekomendacijos egzistuojančios interaktyvios e-mokymo taikomosios programos adaptacijai Grid paslaugų architektūrai. Šios rekomendacijos realizuoja esamą sistemą kaip paslaugą ar paslaugų rinkinį. Sudarytos rekomendacijos praktiškai išbandomos pritaikant realią nuotolinę testavimo sistemą Grid paslaugų aplinkai. Eksperimentinėje dalyje yra įvertinta nauda, kurią suteikia sistemos realizavimas Grid paslaugomis išplečiamumo, lankstumo bei pakartotinio panaudojimo požiūriu. / The increasing amount of information and services on the internet continues to grow, traditional e-learning architectures are unable to satisfy the need of integration, flexibility and resource management. The new service oriented architecture based on web services technologies and Grid environment is the effective and valuable way to develop e-learning. In this master thesis new e-learning opportunities based on service oriented Grid architecture are analyzed. In order to use new approaches the existing system has to be modified. Recommendations for the existing interactive e-learning applications adaptation for the service oriented Grid environment are presented. These recommendations implement the current systems as a service or set of services. The proposed recommendations are tested practically adapting the real distant assessment system for Grid service environment. The added value of this new approach is evaluated taking into consideration scalability, flexibility and reusability of Grid services in the experimentation part.
595

Comparison of optimization for non linear and linear wind resource grids

Dragoi, Ion January 2013 (has links)
The aim of this thesis is to assess how the configuration of linear and non-linearwind resource grids impacts the optimization.Three different software tools are used for this study: WAsP (linear model) includedin WindPRO, and WindSim (a non-linear model) - a CFD tool, and WindPRO forthe optimization. With the same configuration for wind resources, WAsP andWindSim will run to calculate the wind resource grids, .rsf or .wrg format, whichwill be compared in the post processing tab of WindPRO (from CFD interface).Using different optimization algorithms, the results from two software will becompared. The test site is flat terrain in the sea with no complexity (0,0002roughness and no orography or obstacle), and the chosen turbine here is Enercon40.3 (55m hub height, with the rated power at 14 m/s), and the wind is coming fromone direction, in our case North, which means sector 0.After comparison of the resource files from linear and non-linear wind resourcegrids, the optimization and comparison is ran for the two wind resource grids (linearand non-linear). The results of the optimization are also compared with optimizationresults of Eftun Yilmaz’s thesis (Eftun Yilmaz, 2013). We can see from the resultsthat WindSim gives almost 40% bigger values for the production. The results arecomparable with findings of Eftun Yilmaz thesis.
596

SJÄLVFÖRSÖRJANDE BYGGNADER : En studie om lönsamheten av energiförsörjning med solceller i kombination med vätgasbränsleceller / SELF SUSTAINED BUILDINGS : A study about profitability of energy supply by EV-panels combined with hydrogen fuel cells

Karlsson, Patrik, Eriksson, Kim January 2018 (has links)
Syfte: Dagens samhälle blir mer och mer energimedvetet och regeringen sätter upp riktlinjer för bland annat byggsektorn i form av nya regler från Boverket. Ett av den svenska regeringens mål för klimat- och energipolitiken är att till år 2020 minska klimatutsläppen med 40 % och energianvändningen ska vara 20 % effektivare än i dagsläget. Ett led i detta är att bygga byggnader som är mer energieffektiva eller till och med tillverkar sin egen energi. Byggbranschen i Sverige står i dagsläget för cirka 40 % av koldioxidutsläppen, majoriteten av utsläppen sker vid producering av energi som tillförs byggnaderna under brukningsskedet. Målet för arbetet är att granska lönsamheten hos off-grid-förskolor i en mindre kommun i Mellansverige ur ett ekonomiskt perspektiv. Metod: Arbetet är en fallstudie som undersöker projektering av förskolor som planerar byggas i en mindre kommun i Mellansverige. Förskolan ska vara självförsörjande på energi genom att ha solceller på taket tillsammans med vätgasbränsleceller. Med det systemet ska hela byggnadens energibehov kunna tillgodoses. Intervjuer genomförs med de aktörer som ska bygga förskolan, både från beställarsidan och utförarsidan. Dokumentanalys av bygghandlingar används för att göra en LCC-analys som jämför den planerade energikällan mot bergvärme och passivhus. Resultat: Det är inte ekonomiskt lönsamt att använda vätgasbränslecell med solceller som energikälla. LCC-analysen indikerar att det inte är lönsamt att investera i vätgasbränsleceller som energikälla eftersom initialkostnaden är så hög att den inte går att ta igen ekonomiskt under byggnadens livstid jämfört med de andra två alternativ som undersökts. Formfaktorn är bra men det finns utrymme för förbättringar främst i minskad fönsterarea och en mer kvadratisk byggnad som leder till minskad väggarea och därmed lägre byggpris. Både LCC-analysen och intervjuerna indikerar att vätgasbränsleceller är en dyr teknik i dagsläget. Det behövs fler satsningar från politiskt håll för att få igång debatt om bränsleceller och skapa förutsättningar för att företag och privatpersoner ska kunna satsa på tekniken. Det kan dock vara lönsamt för en kommun på andra sätt, till exempel genom att ny industri och fler jobb lockas till kommunen. Konsekvenser: Slutsatsen är att det i dagsläget inte verkar vara lönsamt med vätgasbränslecell som energikälla. Ämnet behöver studeras i större perspektiv där den nya industrin som genereras av kommunens satsning på vätgasbränsleceller tas i beaktning. Begränsningar: Studien utgår från det planerade projektet i Mariestads kommun och har inte jämförts med några andra liknande projekt. Studien tittar på initial- och driftkostnader och tar inte med miljöaspekten i värderingen om lönsamhet. / Purpose: Today’s society is becoming more and more energy conscious and the government sets guidelines for, inter alia, the construction sector in the form of new regulations by the Boverket. One of the Swedish government´s goals for climate and energy policy is to reduce climate emissions by 40% and 20% more efficient energy use than now. A part of this is to build buildings that are more energy efficient or even produce their own energy. The construction industry is Sweden currently accounts for about 40% of the carbon dioxide emissons, the majority of emissions occur in the production of energy supplied to buildings during the use phase. The aim of the work is to review the profitability of off-grid preschools in a small municipality in central Sweden from an economic perspective. Method: This study is a case study that investigates the planned project of kindergartens in a smaller municipality in mid-Sweden. The kindergarten is supposed to be off-grid, self-sustained, in energy using photo voltaic cells on the roof together with hydrogen fuel cells. With this system the entire energy need of the building will be provided. Interviews are performed with participants of the project, both client and contractor. A document analysis is used to make an LCC analysis that compares the intended energy source with a geothermal one and zero energy building. Findings: It is not economically profitable to use hydrogen fuel cell in conjunction with photo voltaic cells as an energy source. The LCC analysis indicates that it is not profitable to invest in hydrogen fuel cells as an energy source since the initial cost is so high that it can´t be recouped within the life span of the building compared to the two other options investigated. The form factor is good but there is room for improvements especially in cut window area and a square shaped building that leads to smaller wall area and therefore less expensive building. Both the LCC analysis and the interviews indicate that hydrogen fuel cells as of today is an expensive technique. More political engagement is required to start debate about fuel cells and to create conditions for companies and individuals to be able to invest in the technique. It can however be profitable for a municipality in other ways, i.e. new industries and more jobs in the municipality. Implications: The conclusion is that it is not economically profitable to use hydrogen fuel cells as an energy source. The subject needs to be studied in a greater context considering the new industries generated by the municipality’s investment in hydrogen fuel cells. Limitations: The study generates from the planned project in Mariestads municipality and has not compared with other similar projects. The study investigates initial costs and maintenance costs and does not consider the environmental aspect in profitability.
597

Agendamento e reserva futura de caminhos ópticos em ambientes de lambda grid por meio de otimização por colônia de formigas

Tinini, Rodrigo Izidoro January 2014 (has links)
Orientador: Prof. Dr. Gustavo Sousa Pavani / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência da Computação, 2014. / Por conta da grande demanda por computação de alto desempenho, maiores taxas de envio de dados e disponibilidade de recursos de um ambiente de computação em grade, este trabalho apresenta um estudo realizado sobre o uso de redes ópticas que operam com Multiplexação por Divisão de Comprimento de Onda (Wavelength Division Multiplexing (WDM)) no suporte a grades computacionais, cujo ambiente é chamado de lambda grid. Assim, é proposto neste trabalho uma nova arquitetura de lambda grid capaz de ampliar a disponibilidade de seus recursos computacionais e de rede, por meio da inserc~ao de um suporte a reserva futura destes recursos, ampliando a disponibilidade da grade a tempos futuros e não apenas a tempos correntes de operação. Para o gerenciamento desse ambiente, foi proposto o uso de um algoritmo baseado em Otimização por Colônia de Formigas (Ant Colony Optimization (ACO)) integrado ao plano de controle Generalized Multi-Protocol Label Switching (GMPLS), o qual é capaz de gerenciar dinamicamente e de forma conjunta os recursos de processamento e de rede, alem de prover os mecanismos de agendamento e de reserva futura desses recursos. A arquitetura proposta, juntamente com os demais algoritmos desenvolvidos, foi testada e validada por meio de simulações. Os resultados das simulações permitiram a avaliação do desempenho da nova arquitetura e da necessidade de se incorporar o agendamento conjunto com reserva futuras na execução da ação da probabilidade de bloqueio. / Due to the increasing demand of high-performance computing, higher data transport rates and the availability of the resources on a grid computing environment, this work presents a study of the use of Wavelength Division Multiplexing (WDM) optical networks on the support of grid computing, whose environment is known as lambda grid. It is proposed in this work a new architecture of lambda grid which is capable of increasing the availability of its network and computing resources by the use of an advance reservation approach, which makes the grid able to other its resources in future times of operation and not only in the current time. For the management of this environment, it was proposed the use of an Ant Colony Optimization (ACO) based algorithm integrated to the Generalized Multi-Protocol Label Switching (GMPLS) control plane, which is capable to dynamically manage the server and network resources, in addition to provide the co-scheduling and advance reservation of those resources. The proposed architecture and algorithms were tested and evaluated by means of simulations. The obtained results allowed the evaluation of the performance of the new architecture and the need to incorporate the co-scheduling of server and optical network resources in their advance reservation in order to minimize the blocking probability.
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Verificação de framework conceitual de avaliação do desempenho de equipes-cliente: investigação a partir da construção de mapas cognitivos de profissionais de TI atuantes em projetos de implantação ERP

Moura Junior, Pedro Jácome de 30 April 2012 (has links)
Made available in DSpace on 2015-04-16T14:48:50Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2591414 bytes, checksum: 7d0876b45145b2d4909efd2ccc9586f4 (MD5) Previous issue date: 2012-04-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / With high degree of breadth on the organisation and interdependence with its processes, the deployment of integrated management systems (ERP Enterprise Resource Planning) is not a simple task. Project management failures, unmet expectations, lengthy deployment deadlines and costs that reach up to five times the value of product licensing itself are among the factors that stimulate the development of research on the organizational consequences of deploying such systems and managerial factors that influence or hinder the success of deployments. It can be seen a predominance of technical focus on the issues inherent in deploying ERP. However, it's growing discontent with the inability of that focus to explain some important aspects in CISS projects. In fact, software development is a complex sociotechnical activity, whose success lies in the collective sense of work teams as to their efficiency and ability to solve problems in joint effort. Accordingly, the focus of research, even in those involving technical and social prospects, has prioritized the technology provider teams performance, or development teams, thus ignoring completely the performance of its counterpart in the success of a deployment the customer team. Working on this subject, Bellini (2006) proposed a conceptual framework, METRICS, for planning, control and evaluation support on the performance of the "CuTe" (customer teams), in implementing customized information systems software (CISS). The framework was applied in the execution of a major project ERP deployment in southern Brazil, adopting case study and indepth interviews with analysts, developers and users-keys (lead users) from the system. Considering the relevance of this discussion, the demand for validation of theoretical models, the calling to methodological diversity in the field and regional differences that may interfere in this validation, this dissertation seeks answer to question: the METRICS framework members constructs are verifiable from the construction of cognitive maps of professionals engaged in CISS projects in Brazilian Northeast? Aiming, therefore, to obtain empirical evidence that contribute to a new and original assessment of the original theoretical constructs and nomological networks contained within the framework. Data collection to answer the research question was enlighted by the theory of personal constructs and repertory grid method, integrated with laddering techniques and content analysis, applied on interviews with 16 professionals involved in CISS projects, while the outcomes were discussed from the socio-technical perspective of work systems. With 68 measures empirically verified, 77.3% METRICS framework found backing in professional practice of individuals engaged in CISS projects in the Brazilian states of Bahia, Paraíba and Pernambuco. Discussion of conceptual and theoretical results suggests METRICS framework s actuality, as well as its suitability for broader research on professional management and IT teams. / Com elevado grau de abrangência sobre a organização e interdependência com seus processos, a implantação de sistemas integrados de gestão (ERP enterprise resource planning) não é tarefa simples. Falhas de gestão de projetos, expectativas não atendidas, longos prazos de implantação e custos que alcançam até cinco vezes o valor de licenciamento do produto em si estão entre os fatores que estimulam o desenvolvimento de pesquisas sobre as consequências organizacionais da implantação de tais sistemas e os fatores gerenciais que influenciam ou dificultam o sucesso das implantações. Observa-se predominância de enfoque técnico sobre as questões inerentes à implantação ERP. No entanto, é crescente o descontentamento com a incapacidade desse enfoque em explicar alguns aspectos importantes em projetos. De fato, o desenvolvimento de software é uma complexa atividade sociotécnica, cujo sucesso reside no senso coletivo das equipes de trabalho quanto à sua eficiência e capacidade de resolver problemas em esforço conjunto. Nesse sentido, verifica-se que o foco das pesquisas, mesmo aquelas envolvendo as perspectivas técnica e social, tem priorizado o desempenho das equipes provedoras de tecnologia, ou equipes de desenvolvimento, assim ignorando quase por completo o desempenho de sua contraparte no sucesso de implantações a equipe-cliente. Trabalhando sobre essa temática, Bellini (2006) propôs o framework conceitual METRICS para apoio ao planejamento, controle, avaliação e registro do desempenho de equipes-clientes (CuTes customer teams) em projetos de desenvolvimento de sistemas de informação customizados (CISS). O framework foi aplicado na execução de um grande projeto de implantação ERP na Região Sul do Brasil, adotando estudo de caso e entrevistas em profundidade com analistas, desenvolvedores e usuários-chaves (lead users) do sistema. Considerando a relevância dessa discussão, a demanda por validação de modelos teóricos, o chamado à diversidade metodológica no campo e diferenças regionais que possam interferir nessa validação a presente dissertação busca resposta à seguinte questão de pesquisa: Os construtos do framework METRICS são verificáveis a partir da construção de mapas cognitivos de profissionais de TI atuantes em projetos CISS no Nordeste? Objetiva-se, portanto, obter evidências empíricas que contribuam para uma nova e original validação dos construtos e redes nomológicas daquele framework. A obtenção dos dados para resposta à questão de pesquisa se deu à luz da teoria dos construtos pessoais e do método repertory grid integrado a técnicas de laddering e análise de conteúdo, com aplicação em entrevistas com 16 profissionais de TI atuantes em projetos CISS, e os resultados foram discutidos sob a perspectiva sociotécnica dos sistemas de trabalho. Com 68 medidas verificadas empiricamente, 77,3% do framework METRICS encontrou respaldo na prática profissional de indivíduos engajados em projetos CISS nos estados da Bahia, Paraíba e Pernambuco. Os resultados sugerem a atualidade conceitual e aplicada do framework METRICS em projetos CISS, bem como sua adequação para a realização de pesquisas mais abrangentes sobre gestão de profissionais e equipes de TI.
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Escalonamento de tarefas em ambiente de simulação de grid computacional /

Franco, Patrícia Batista. January 2011 (has links)
Orientador: Roberta Spolon / Banca: Sarita Mazzini Brushi / Banca: Marcos Antônio Cavenaghi / Resumo: Diversos são os esforços para o desenvolvimento de políticas de escalonamento em grid computacional. O uso de simuladores de grid computacional é de especial importância para o estudo de algoritmos de escalonamento de tarefas. Através dos simuladores, é possível avaliar e comparar o desempenho de diferentes algoritmos em diferentes cenários. Apesar das ferramentas de simulação fornecerem funcionalidades básicas para simulação de ambientes distribuídos, elas não disponibilizam políticas internas de escalonamento de tarefas; além disso, a implementação dos algoritmos deve ser feita pelo próprio usuário. Portanto, o objetivo deste trabalho é desenvolver a biblioteca de escalonamento de tarefas LIBTS (Library Tasks Scheduling) e adaptá-la ao simulador SimGrid para oferecer aos usuários uma ferramenta que possibilite o estudo de algoritmos de escalonamento de tarefas em grid computacional. Através da LIBTS os usuários podem comparar os algoritmos implementados (Workqueue (WQ), Workqueue with Replication (WQR), Sufferage, XSufferage, Dynamic FPLTF) em diversos cenários, como também desenvolver e implementar novos algoritmos de escalonamento de tarefas. Este trabalho também proporciona uma revisão de literatura sobre grid computacional, apresentando as características e metodologias dos algoritmos implementados na LIBTS e as principais características das ferramentas de simulação. Além disso, os cenários de testes criados para comparar os algoritmos validaram o funcionamento da biblioteca e o funcionamento correto dos algoritmos na LIBTS / Abstract: Too much has been done to develop scheduling policies in computational grid. The use of computational grid simulators is particularly important for studying the algorithms of task scheduling. Through the simulators it's possible to assess and compare the performance of different algorithms in various scenarios. Despite the simulation tools provide basic features for simulation in distributed environments, they don't offer internal policies of task scheduling, so that the implementation of the algorithms must be realized by the user himself. Therefore, this study aims to develop the library of task scheduling LIBTS (Library Tasks Scheduling) and adapt it to the SimGrid simulator to provide the users with a tool to analyze the algorithms of task scheduling in the computational grid. Through the LIBTS, the users can compare the implemented algorithms (Workqueue (WQ), Workqueue with Replication (WQR), Sufferage, XSufferage, Dynamic FPLTF) in several scenarios, as well as to develop and implement new algorithms of task scheduling. This work also provides a literature review about the computational grid, presenting the characteristics and methodologies of the implemented algorithms in the LIBTS and the most important features of the simulation tools. Furthermore, the test scenarios created to compare the algorithms validate the library operation and the correct operation of the algorithms in LIBTS / Mestre
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Um serviço de metadados integrado ao middleware de grade MAG / An integrated service of metadata to middleware of grating MAG

Sousa, Bysmarck Barros de 10 July 2006 (has links)
Made available in DSpace on 2016-08-17T14:53:01Z (GMT). No. of bitstreams: 1 Bysmarck Barros de Sousa.pdf: 4248162 bytes, checksum: 1b6440a084fcf6e55f08f5faaa29694e (MD5) Previous issue date: 2006-07-10 / The computation in grating allows to the integration and sharing of resources as softwares, data and hardware, in institucional and multiinstitucional environments. Recently, had to the great volume of generated data the most varied dominios of application, applications that carry through intensive computation has been wide used. The Mag Cat foca in the challenge of the discovery and publication of the data shared in a grating of computers. MagCat was developed using the technology of software agents, using the great capacity of abstraction of this technology. / A computação em grade permite a integração e compartilhamento de recursos como softwares, dados e périfericos, em ambientes institucionais e multiinstitucionais. Recentemente, devido ao grande volume de dados gerados os mais variados dominios de aplicação, aplicações que realizam computação intensiva tem sido largamente utilizadas. O Mag Cat foca no desafio da descoberta e publicação dos dados compartilhados em uma grade de computadores. MagCat foi desenvolvido usando a tecnologia de agentes de software, utilizando a grande capacidade de abstração desta tecnologia.

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