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A model for material handling improvements when using automated storage systems: A case study / En modell för förbättringar av materialhantering genom användandet av automatiserade lagersystem: En fallstudieThongmal Larsson, Marie January 2010 (has links)
The purpose of this thesis is to create a model of how to organize the placements of articles in an automated storage system in order to reduce time and cost related to the extractions. The model was developed during an investigation at a case company, and a comprehensive study of the material handling identified bottlenecks, whereof one was chosen to be further investigated: the automated storage system. The automated storage system is newly installed equipment, which required new working methods to be incorporated to the already existing working environment. The ABC-analysis was used in order to motivate how the articles should be placed in the automated storage. The goal for the new way of handling material was to put as little effort as possible on time related to the extraction of material. This due to the realization of material handling processes being a huge contributor to waste activities. This resulted in the development of the model and the suggestion that is given to the case company is to place the most frequent extracted articles close to the users. However, advantages must be held against disadvantages of rearrangements since the material handling will not be eliminated totally due to smaller improvements. / Syftet med denna uppsats är att skapa en modell för hur man ska organisera artikelplaceringar i ett automatiserat lagersystem för att reducera tid och kostnad relaterat till uttag av material. Modellen skapades genom en undersökning på ett fallföretag, en omfattande studie av materialhanteringen identifierade flaskhalsar, varav en valdes för fortsatt undersökning: det automatiserade lagersystemet. Det automatiserade lagersystemet är en nyinstallerad utrustning, som kräver att nya arbetsmetoder ska inkorporeras till den redan existerande arbetsmiljön. ABC-analysen användes för att motivera hur artiklarna ska placeras i det automatiserade lagret. Målet för det nya sättet att hantera material på var att så få insatser som möjligt skulle användas för uttag av material. Detta pågrund av insikten utav att materialhanteringsprocesser är en stor bidragande slöserifaktor. Detta resulterade i modellen och förslagen som ges till fallföretaget är att placera de mest frekvent använda artiklarna nära användaren. Emellertid så måste man väga fördelar mot nackdelar av en förändring eftersom materialhanteringen inte kommer att elimineras helt pågrund av mindre förbättringar.
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Data and application migration in cloud based data centers --architectures and techniquesZhang, Gong 19 May 2011 (has links)
Computing and communication have continued to impact on the way we run business, the way we learn, and the way we live. The rapid technology evolution of computing has also expedited the growth of digital data, the workload of services, and the complexity of applications. Today, the cost of managing storage hardware ranges from two to ten times the acquisition cost of the storage hardware. We see an increasing demand on technologies for transferring management burden from humans to software. Data migration and application migration are one of popular technologies that enable computing and data storage management to be autonomic and self-managing.
In this dissertation, we examine important issues in designing and developing scalable architectures and techniques for efficient and effective data migration and application migration. The first contribution we have made is to investigate the opportunity of automated data migration across multi-tier storage systems. The significant IO improvement in Solid State Disks (SSD) over traditional rotational hard disks (HDD) motivates the integration of SSD into existing storage hierarchy for enhanced performance. We developed adaptive look-ahead data migration approach to effectively integrate SSD into the multi-tiered storage architecture. When using the fast and expensive SSD tier to store the high temperature data (hot data) while placing the relatively low temperature data (low data) in the HDD tier, one of the important functionality is to manage the migration of data as their access patterns are changed from hot to cold and vice versa. For example, workloads during day time in typical banking applications can be dramatically different from those during night time. We designed and implemented an adaptive lookahead data migration model. A unique feature of our automated migration approach is its ability to dynamically adapt the data migration schedule to achieve the optimal migration effectiveness by taking into account of application specific characteristics and I/O profiles as well as workload deadlines. Our experiments running over the real system trace show that the basic look-ahead data migration model is effective in improving system resource utilization and the adaptive look-ahead migration model is more efficient for continuously improving and tuning of the performance and scalability of multi-tier storage systems. The second main contribution we have made in this dissertation research is to address the challenge of ensuring reliability and balancing loads across a network of computing nodes, managed in a decentralized service computing system. Considering providing location based services for geographically distributed mobile users, the continuous and massive service request workloads pose significant technical challenges for the system to guarantee scalable and reliable service provision. We design and develop a decentralized service computing architecture, called Reliable GeoGrid, with two unique features. First, we develop a distributed workload migration scheme with controlled replication, which utilizes a shortcut-based optimization to increase the resilience of the system against various node failures and network partition failures. Second, we devise a dynamic load balancing technique to scale the system in anticipation of unexpected workload changes. Our experimental results show that the Reliable GeoGrid architecture is highly scalable under changing service workloads with moving hotspots and highly reliable in the presence of massive node failures. The third research thrust in this dissertation research is focused on study the process of migrating applications from local physical data centers to Cloud. We design migration experiments and study the error types and further build the error model. Based on the analysis and observations in migration experiments, we propose the CloudMig system which provides both configuration validation and installation automation which effectively reduces the configuration errors and installation complexity. In this dissertation, I will provide an in-depth discussion of the principles of migration and its applications in improving data storage performance, balancing service workloads and adapting to cloud platform.
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Studentų darbų įkėlimo ir kaupimo sistema / Students Works Loading and Storage System,Kuprys, Ignas 07 September 2010 (has links)
„Studentų darbų įkėlimo ir kaupimo sistema“ - tai sistema kuri palengvina darbą dėstytojams su studentų darbų įkėlimu ir jų kaupimu. Dėstytojai kuria modulius ir atsiskaitymus jiems. Moduliams gali priskirti studentus, arba suteikti galimybe patiems studentams prisiregistruoti prie modulio, žinant modulio raktą. Parsisiųsti ar ištrinti atsiskaitymų failus. Importuoti, eksportuoti vartotojus. Nustatyti kokio dydžio, tipo failus galima įkelti į sistemą. Studentai gali užsiregistruoti moduliui, jei žino modulio raktą. Peržiūrėti kokie moduliai priskirti, kokie atsiskaitymai jiems sukurti. Įkelti atsiskaitymams failus. Peržiūrėti įkeltų failų sąrašą. / “Students Works Loading and Storage System“ a system that facilitate the work of students and university professors with file uploads and their accumulation. Teachers can create modules, assignments. Enroll users to modules. Set upload time limit, visibility, max file size and file type to assignments. Delete or download uploaded files. Import, export or delete users. Students may register to module. In one place see all attached modules and assignments, upload files. See the list of uploaded files.
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Impact of Solar Resource and Atmospheric Constituents on Energy Yield Models for Concentrated Photovoltaic SystemsMohammed, Jafaru 24 July 2013 (has links)
Global economic trends suggest that there is a need to generate sustainable renewable energy to meet growing global energy demands. Solar energy harnessed by concentrated photovoltaic (CPV) systems has a potential for strong contributions to future energy supplies. However, as a relatively new technology, there is still a need for considerable research into the relationship between the technology and the solar resource. Research into CPV systems was carried out at the University of Ottawa’s Solar Cells and Nanostructured Device Laboratory (SUNLAB), focusing on the acquisition and assessment of meteorological and local solar resource datasets as inputs to more complex system (cell) models for energy yield assessment.
An algorithm aimed at estimating the spectral profile of direct normal irradiance (DNI) was created. The algorithm was designed to use easily sourced low resolution meteorological datasets, temporal band pass filter measurement and an atmospheric radiative transfer model to determine a location specific solar spectrum. Its core design involved the use of an optical depth parameterization algorithm based on a published objective regression algorithm. Initial results showed a spectral agreement that corresponds to 0.56% photo-current difference in a modeled CPV cell when compared to measured spectrum.
The common procedures and datasets used for long term CPV energy yield assessment was investigated. The aim was to quantitatively de-convolute various factors, especially meteorological factors responsible for error bias in CPV energy yield evaluation. Over the time period from June 2011 to August 2012, the analysis found that neglecting spectral variations resulted in a ~2% overestimation of energy yields. It was shown that clouds have the dominant impact on CPV energy yields, at the 60% level.
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Optimal predictive control of thermal storage in hollow core ventilated slab systemsRen, Mei Juan January 1997 (has links)
The energy crisis together with greater environmental awareness, has increased interest in the construction of low energy buildings. Fabric thermal storage systems provide a promising approach for reducing building energy use and cost, and consequently, the emission of environmental pollutants. Hollow core ventilated slab systems are a form of fabric thermal storage system that, through the coupling of the ventilation air with the mass of the slab, are effective in utilizing the building fabric as a thermal store. However, the benefit of such systems can only be realized through the effective control of the thermal storage. This thesis investigates an optimum control strategy for the hollow core ventilated slab systems, that reduces the energy cost of the system without prejudicing the building occupants thermal comfort. The controller uses the predicted ambient temperature and solar radiation, together with a model of the building, to predict the energy costs of the system and the thermal comfort conditions in the occupied space. The optimum control strategy is identified by exercising the model with a numerical optimization method, such that the energy costs are minimized without violating the building occupant's thermal comfort. The thesis describes the use of an Auto Regressive Moving Average model to predict the ambient conditions for the next 24 hours. A building dynamic lumped parameter thermal network model, is also described, together with its validation. The implementation of a Genetic Algorithm search method for optimizing the control strategy is described, and its performance in finding an optimum solution analysed. The characteristics of the optimum schedule of control setpoints are investigated for each season, from which a simplified time-stage control strategy is derived. The effects of weather prediction errors on the optimum control strategy are investigated and the performance of the optimum controller is analysed and compared to a conventional rule-based control strategy. The on-line implementation of the optimal predictive controller would require the accurate estimation of parameters for modelling the building, which could form part of future work.
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An internship in technical and scientific communication with Dell Inc.Hawkins, Steve. January 2003 (has links)
Thesis (M.T.S.C.)--Miami University, Dept. of English, 2003. / Title from first page of PDF document. Includes bibliographical references (p. 105).
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Dimensionnement et contrôle-commande optimisé des systèmes de stockage énergétique pour la participation au marché de l'électricité des parcs photovoltaïques intelligents / Optimal sizing and control of energy storage systems for the electricity markets participation of intelligent photovoltaic power plantsSaez de ibarra martinez de contrasta, Andoni 07 October 2016 (has links)
L’objet de cette thèse est l’intégration des parcs photovoltaïques intelligents au marché de l’électricité dans un environnement de libre concurrence. Les centrales photovoltaïques intelligentes sont celles qu’incluent systèmes de stockage pour réduire sa variabilité et en plus fournir à l’ensemble une plus grande contrôlabilité. Ces objectives techniques sont obtenues grâce à la capacité bidirectionnelle d’échange et stockage d’énergie qu’apportent les systèmes de stockage, dans ce cas, les batteries. Pour obtenir la rentabilité maximale des systèmes de stockage, le dimensionnement doit être optimisé en même temps que la stratégie de gestion avec laquelle le système de stockage est commandé. Dans cette thèse, une fois la technologie de stockage plus adapté à l’application photovoltaïque est sélectionnée, à savoir la technologie de lithium-ion, une participation innovatrice de part des parcs photovoltaïques intelligents dans le marché de l’électricité est proposée qui optimise à la fois le dimensionnement et la stratégie de gestion d’une manière simultanée. Ce processus d'optimisation ainsi que la participation au marché de l'électricité a été appliquée dans un cas d’étude réel, ce qui confirme que cette procédure permet de maximiser la rentabilité économique de ce type de production. / The present PhD deals with the integration of intelligent photovoltaic (IPV) power plants in the electricity markets in an environment subject to free competition. The IPV power plants are those that include energy storage systems to reduce the variability and to provide the entire group a controllability increase. These technical objectives are obtained thanks to the bidirectional exchanging and storing capability that the storage system contributes to, in this case, battery energy storage system (BESS). In order to obtain the maximum profitability of the BESS, the sizing must be optimized together with the control strategy that the BESS will be operated with. In the present PhD, once the most performing battery energy storage technology has been selected, the lithium-ion technology, an innovative IPV power plant electricity market participation process is proposed which optimizes both the sizing and the energy management strategy in the same optimization step. This optimization process together with the electricity market participation has been applied in a real case study, confirming that this procedure permits to maximize the economic profitability of this type of generation.
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Intégration du stockage dans les méthodes de planification des réseaux électriques basse tension / Storage Integration in the planning methods of low voltage gridHadj said, Ahmed 31 January 2018 (has links)
L’ouverture des marchés de l’énergie et les nouveaux usages ont induit à des changements significatifs sur les réseaux de distribution (le réseau basse tension – BT – notamment), comme : l’augmentation des interconnections de production à partir de sources d’énergies renouvelables (EnR), l’accroissement de la pointe de consommation, entre autres. Ces derniers créent des contraintes électriques. Dans l’optique d’une gestion pragmatique des réseaux électriques intelligents, des gisements de flexibilité comme le pilotage des charges/sources ou le stockage sont recherchés pour offrir des nouvelles solutions à ces contraintes. Cette thèse étudie ainsi les enjeux de la gestion du stockage et son impact dans les méthodes de planification des réseaux BT. Ainsi, dans un premier temps, les impacts du stockage et de la production photovoltaïque sur des grandeurs utilisées dans la planification des réseaux de distribution sont étudiés. Dans un second temps, une méthode de calcul des coûts des pertes est adaptée à la présence du stockage et/ou de la production PV. Dans une dernière partie, des algorithmes de fonctions avancées de conduite sont développés afin d’illustrer la valeur économique du stockage dans la planification des réseaux BT, et comparés à une planification classique plus couteuse. / The opening up of energy markets and new uses have led to significant changes in distribution grids, in particular low-voltage grids. Notably, it has led to an augmentation in the integration of renewable energy production, an increase in the peak consumption, among others. This is accompanied by the appearance of the electrical constraints with which power systems must cope. This has resulted in the development multiple flexibility capabilities such as load/source management or energy storage, providing new solutions, now to be considered in planning methods. This thesis studies the issue of energy storage in the low-voltage grid planning. The first part of this thesis studies the impact of storage and photovoltaic production on variables involved in distribution grid planning. In the second part, a method for calculating the cost of losses is adapted to the presence of energy storage and/or PV production. Finally, advanced d operation algorithms are developed to illustrate the economic value of energy storage in LV distribution grid planning, compared to a more expensive conventional planning method.
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Thermodynamics of Distributed Solar Thermal Power Systems with StorageGarg, Pardeep January 2015 (has links) (PDF)
Distributed power generation through renewable sources of energy has the potential of meeting the challenge of providing electricity access to the off-grid population, estimated to be around 1.2 billion residing across the globe with 300 million in India, in a sustainable way. Technological solutions developed around these energy challenges often involve thermal systems that convert heat available from sources like solar, biomass, geothermal or unused industrial processes into electricity. Conventional steam based thermodynamic cycle at distributed scale (< 1 MWe) suffers from low efficiency driving scientific research to develop new, scalable, efficient and economically viable power cycles. This PhD work conducts one such study which provides a database of thermal power blocks optimized for the lowest initial investment cost to developers of distributed power plants. The work is divided in two steps; a) feasibility study of various thermodynamic cycles for distributed power generation covering different operating temperature regimes and b) perform their detailed thermo-economic modelling for the heat sources mentioned above.
Thermodynamic cycles are classified into three temperature domains namely, low (< 450 K), medium (< 600 K) and high (< 1000 K) T cycles. Any fluid whose triple point temperature is below the typical ambient temperatures is a potential working fluid in the power cycle. Most of the organic and the inorganic fluids satisfy this criterion and can be perceived as potential power cycle fluids. The general notion is that organic fluids are more suited for low or medium temperature cycles whereas inorganic fluids for high temperature ones. Organic fluids can further be classified into hydrofluorocarbon and hydrocarbon. While the former has high global warming potential (GWP), the latter is flammable in nature. Their mixture in certain compositions is found to obviate both the demerits and perform equally well on thermodynamic scales for low T cycles. On the similar lines, mixture of HCs and inorganic fluids, such as propane+CO2 and isopentane+CO2 are found to be more appropriate for medium T applications if the issues like pinch temperature in the regenerator arising due to temperature glide are taken care of.
In the high temperature domain, high efficiency Brayton cycle (supercritical CO2) and transcritical condensing cycles are studied with the latter being 2 % more efficient than the former. However, application of the condensing cycle is limited to low temperature ambient locations owing to low critical temperature of CO2 (304 K). In the same cycle configuration,
mixture of CO2 and propane (52 and 48%) with a critical temperature of ~ 320 K is observed to retain the thermodynamic performance with the increased heat rejection temperature matched to the tropical ambient conditions. However, these cycles are plagued by the high operating pressures (~300 bar) calling for high temperature steel making the power block uneconomical. In this regard, the advanced CO2 cycles are developed wherein the optimum operating pressures are limited to 150 bar with an increased cycle efficiency of 6 % over the S-CO2 cycle. Feasibility study carried out on these cycles in the Indian context indicates the low and medium T cycles to be better suited for distributed power generation over the high T cycles.
In the second part of work, a comprehensive study is performed to optimize the low and the medium T cycles on a thermo-economic basis for the minimum specific investment cost ($/We). Such a study involves development of component level models which are then integrated to form the system of interest, thus, following a bottom-up approach. A major emphasis is given on the development of scroll expander and low cost pebble bed thermal energy storage system that are the reported in the literature as the areas with high uncertainties while connecting them to the system. Subsequently, the key design parameters influencing the specific cost of power from an air-cooled ORC are identified and used to formulate a 7-dimensional space to search for the minimum costs for applications with a) geothermal/waste or biogas heat sources and b) solar ORCs. Corresponding maps of operating parameters are generated to facilitate distributed power engineers in the design of economic systems within constraints such as available heat source temperatures, maximum expander inlet pressures imposed, etc. Further, the effect of power scaling on these specific costs is evaluated for ORC capacities between 5 and 500 kWe.
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Qualidade de Grãos de Feijão Armazenados sob Atmosfera Modificada / Quality of beans stored under modified atmosphereFreitas, Romenique da Silva de 18 March 2009 (has links)
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Previous issue date: 2009-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The study was conducted at the Experimental Farm Rafael Fernandes, Mossoró city, Rio Grande do Norte State, Brazil, with the objective to verify the effect of irrigation levels and planting densities on the castor bean production, BRS ENERGIA . Thus, we used the experimental design in randomized blocks in a split-plot 5 x 2, with four replications. The treatments consisted of irrigation levels (0.6, 0.8, 1.0, 1.2 and 1.4 of ETc) in main plots and plant densities in the sub-plots formed by arrangements 1.50 m x 0.30 m x 0.30 m (D1 - 37,037 plants ha-1) and 1.50 m x 0.30 m x 0.40 m (D2 - 27,778 plants ha-1). The main plots were 18 m in length, 9 m for each of the densities. The irrigation levels were differentiated by the application time using the tubes, each of which had a strip of the water distribution system independent. The main bunches fruits income decreased with the applied levels and the secondary bunches income (in fruits and grains) followed quadratic polynomial model. How much to the total income, was gotten 3,974 kg ha-1 of fruits and 2,691 kg ha-1 of grains with irrigation based on 1,20 and 1,25 of the etc, respectively. / FREITAS, Romenique da Silva. Qualidade de grãos de feijão armazenados sob atmosfera modificada. Mossoró, UFERSA, 2009. 62 f. Dissertação (Mestrado em Agronomia: Fitotecnia) Universidade Federal Rural do Semi-Árido (UFERSA), Mossoró-RN, 2009. Professor Orientador: D. Sc. Patrício Borges Maracajá. Co- orientador: Profa. D. Sc. Lêda Rita D Antonino Faroni. Conselheiros: Prof. D. Sc. Glauber Henrique de Sousa Nunes e Profa. D. Sc. Danila Kelly Pereira Neri.
Este trabalho teve por objetivo avaliar a qualidade de grãos de feijão com diferentes teores de água, armazenados em condições herméticas, ao longo do armazenamento. O experimento foi realizado no Setor de Pré-Processamento e Armazenamento de Produtos Agrícolas do Departamento de Engenharia Agrícola da Universidade Federal de Viçosa (UFV). Foram utilizados grãos de feijão (Phaseolus vulgaris L.) do grupo vermelho, cultivar vermelhinho, com teores de água de 12,3, 15,7 e 17,8% b.u., produzidos na safra de inverno (2008), no município de Viçosa-MG. Os grãos foram acondicionados em embalagens herméticas e armazenados em câmara climática, por 0, 30, 60, 90 e 120 dias, à temperatura de 25 °C e umidade relativa de 70±5%. No armazenamento foram utilizadas bolsas plásticas, impermeáveis com capacidade para três quilogramas e garrafas pet transparente com capacidade para 1,5 L. O delineamento utilizado foi o inteiramente casualizado, em esquema fatorial com parcelas subdivididas e três repetições, sendo as parcelas representadas pelo fatorial condição de armazenamento (silo tipo bolsa, garrafa pet e testemunha) e teor de água do grão (12,3, 15,7 e 17,8% b.u.) e as subparcelas representadas pelos períodos de armazenamento (0, 30, 60, 90 e 120 dias). Avaliou-se o teor de água, grau de infestação por insetos-praga, massa específica aparente, condutividade elétrica, percentual de germinação, tempo de cocção e classificação dos grãos, após cada período de armazenamento. Todas as variáveis analisadas variaram significativamente (p<0,05) entre os teores de umidade, condições (hermética/não
hermética) e períodos de armazenamento. Grãos de feijão com teores de água de 12,3 e 15,7% b.u., armazenados em condições herméticas, mantiveram as características analisadas por 120 dias, exceto o tempo de cocção. Grãos de feijão com teores de água de 17,8% b.u., armazenados em condições herméticas, mantiveram as características analisadas por um período de 60 dias, exceto o tempo de cocção. A perda de qualidade, caracterizada pelo aumento no tempo de cocção, foi maior nos grãos com maior teor de água, armazenados em condições herméticas. Nos grãos com menor teor de água o tempo de cocção foi mantido por 90 dias. O armazenamento hermético é capaz de manter a qualidade de grãos de feijão com teores de água variando de 12,3 a 15,7% b.u. por 120 dias.
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