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Denna rapport tar upp teorin bakom sannolikhet, backuper och hårddiskar. Baserat på detta implementeras en backup-plan med hjälp av NASar, för att ersätta den redan existerande lösningen. Behovet utav en säkrare, mer tillförlitlig backup, samt expansionsmöjligheter då företaget har en stark tillväxt, lades fram tillsammans med en budget för att ta fram en lösning anpassad utefter det faktiska behovet. Denna plan baseras på teorin i kombination med tredje-parts resultat och har som utgångspunkt den budgeten som erhållits utav företaget, för att slutligen uppnå en hållbar, expanderbar och automatiserad backup. Fortsättningsvis behandlar rapporten implementering i existerande infrastruktur, automation och enkel hantering utav backup och varför en 3-2-1 lösning bör användas. Rapporten ser att efter den nya lösningen har implementerats är det mycket mindre risk för att data går förlorat samt att en övergripande ökning i hastighet och automation kan ses. Slutligen, med hjälp av standardiserat verktyg lägger denna rapport en godkänd grund för andra att använda i deras implementationer eller att gräva djupare inom tillförlitlighets världen. / This report handles the theory behind probability, backups and hard drives. Based on this, a backup-scheme is implemented with the help of NASes, to replace the current solution. The need for a more secure, more reliable and a solution that is expandable due to the quick growth of the company, was put forward together with a budget to provide a solution suited after the effective need. This scheme is based upon theory in combination with third-party results and for this specific case has the budget, provided by the company, as a starting point to accomplish a sustainable, expandable and automated backup. Furthermore, this report implements this solution into the existing infrastructure where automation and simple handling of backups and why a 3-2-1 solution will be used. The report finds that after the new solution is implemented there is significantly less risk of data failure as well as an overall increase in speed and automation. Finally, with the help of standardized tools this report lay a decent groundwork for others to use in their implementation or to dig deeper into the world of reliability.

As cloud computing and massive-data machine learning are applied pervasively, ultra-high volume data storage serves as the foundation block. Every day, nearly 2.5 quintillion bytes (50000 GB/second in 2018) of data is created and stored. Hard Disk Drive (HDD) takes major part of this heavy duty. However, despite the amazing evolution of HDD technology during the past 50 years, the conventional Perpendicular Magnetic Recording (PMR), the state-of-the-art HDD technique, starts to have less momentum in increasing storage density because of the recording trilemma. To overcome this, Heat-Assisted Magnetic Recording (HAMR) was initially proposed in 1990s. With years of advancement, recent industrial demos have shown the potential of HAMR to actually break the theoretical limit of PMR. However, to fully take advantage of HAMR and realize the commercialization, there are still quite a few technical challenges, which motivated this thesis work. Via thermal coupled micromagnetic simulation based upon Landau-Lifshitz-Bloch (LLB) equation, the entire dynamic recording process has been studied systematically. The very fundamental recording physics theorem is established, which manages to elegantly interpret the previously conflicting experimental observations. The thermal induced field dependence of performance, due to incomplete switching and erase-after-write, is proposed for the first time and validated in industrial lab. The combinational effects form the ultimate physical limit of this technology. Meanwhile, this theorem predicts the novel noise origins, examples being Curie temperature distribution and temperature distribution, which are the key properties but ignored previously. To enhance performance, utilizations of higher thermal gradient, magnetically stiffer medium, optimal field etc. have been suggested based upon the theorem. Furthermore, a novel concept, Recording Time Window (RTW), has been proposed. It tightly correlates with performance and serves as a unified optimization standard, summarizing almost all primary parameters. After being validated via spin stand testing, the theorem has been applied to provide solutions for guiding medium design and relaxing the field and heating requirement. This helps solve the issues around writer limit and thermal reliability. Additionally, crosstrack varying field has been proposed to solve the well-known transition curvature issue, which may increase the storage density by 50%.

O presente trabalho está focado no método de perfuração direcional horizontal (HDD) para instalação de redes de esgoto gravitacional. Descrevem-se os resultados de diferentes técnicas com o objetivo de se atingir a exigência de declividade. Para tanto foram executados 4 furos experimentais simulando trechos daquelas redes, com extensão de 30 m e tubulação de PEAD com diâmetro externo de 125 mm. Estas instalações foram executadas na cidade de São Carlos, Brasil, em um solo classificado granulometricamente como uma areia argilosa. Para cada uma das 4 instalações, adotou-se um processo construtivo diferenciado. Esta diferenciação se deu a partir do diâmetro do alargador adotado, do número de passadas do mesmo e da execução de furos verticais para alívio de pressão no espaço anelar assim como medidas diretas de profundidade do furo piloto. Após a instalação dos dutos foram realizadas medidas altimétricas no interior dos mesmos possibilitando avaliar quantitativamente os resultados obtidos. Estes resultados indicam que ainda é necessário refinar a técnica de perfuração direcional para a execução das redes de esgoto. Entretanto é possível observar que as variações empregadas na execução de cada um dos furos conduzem a um caminho de melhoria nos resultados obtidos. Esta melhoria pode ser observada nos furos onde o alargador adotado apresentava menor diâmetro conduzindo a menores desvios na posição final do duto. Salientam-se também os benéficos resultados da execução dos furos verticais que conduziram a menores pressões no espaço anelar assim como possibilitaram medidas altimétricas diretas da posição do furo piloto. Desta forma, é provável que com um maior número de experimentos e incrementos tecnológicos se atinja o objetivo final, ou seja, executar redes de esgoto gravitacional com declividade constante e baixa. Em paralelo nas instalações executadas foram realizados testes para avaliação da precisão e acurácia do sistema de navegação responsável pelo fornecimento de informações de posição e temperatura da ferramenta de corte durante a execução do furo piloto. Este trabalho contempla ainda, a elaboração de uma nova solução para as instalações de esgoto executadas através do HDD. Esta solução propõe a aplicação de um esforço de tração a um elemento externo, uma geogrelha que envolve a tubulação, visando posicionar a mesma em declividade constante. Face a seu caráter inovador foram desenvolvidos equipamentos e procedimentos de ensaio de laboratório, para avaliar a aplicabilidade da solução na prática / The present work is focused on the horizontal directional drilling (HDD) method to install gravity sewers. The results of different techniques are described intending to meet the demands of gradient. Therefore, 4 experimental pilot bores were drilled simulating a section of those structures extending 30 m with HDPE pipelines of 125 mm external diameter. Those installations were engineered in the city of São Carlos, Brazil, in a clayey sand. For each of the 4 installations a distinct constructive process was adopted. Such characteristic was on account of the diameter of the selected reamer, the number of reamer steps and the vertical drills performed to relieve the pressure in the annular space, as well as the direct depth measurements of the pilot hole. After installing the pipes, altimetric measurements were performed inside them, hence enabling to quantitatively assess the obtained results. These results indicate the need to further refine the directional drilling technique for sanitary sewers. Yet it can be seen that the employed variations for each of the holes lead to an improved course of action with the observed results. Such improvement is perceived in the holes where the selected reamer had a smaller diameter, hence allowing for less displacement in the pipes final position. Also emphasized are the resulting benefits of the vertical drills that lead to less pressure in the annular space, as well as enabling altimetric measurements of the pilot hole position. Thus, it is presumed that with further experiments and technological developments the final objective is reached, meaning, putting into effect constant and low level gradient sewer networks. Tests for precision and accuracy assessment of the tracking system were also performed in each tube installed. The tracking system is responsible for providing information related to position and temperature of the drill head during the drilling operation. The steps for the development of a new HDD solution for sewer installation are presented. The idea is based on the application of a tensile force to an element external to the product, aiming at attaining a constant gradient. Equipments and procedures developed for this new technique are described.

O presente trabalho está focado no método de perfuração direcional horizontal (HDD) para instalação de redes de esgoto gravitacional. Descrevem-se os resultados de diferentes técnicas com o objetivo de se atingir a exigência de declividade. Para tanto foram executados 4 furos experimentais simulando trechos daquelas redes, com extensão de 30 m e tubulação de PEAD com diâmetro externo de 125 mm. Estas instalações foram executadas na cidade de São Carlos, Brasil, em um solo classificado granulometricamente como uma areia argilosa. Para cada uma das 4 instalações, adotou-se um processo construtivo diferenciado. Esta diferenciação se deu a partir do diâmetro do alargador adotado, do número de passadas do mesmo e da execução de furos verticais para alívio de pressão no espaço anelar assim como medidas diretas de profundidade do furo piloto. Após a instalação dos dutos foram realizadas medidas altimétricas no interior dos mesmos possibilitando avaliar quantitativamente os resultados obtidos. Estes resultados indicam que ainda é necessário refinar a técnica de perfuração direcional para a execução das redes de esgoto. Entretanto é possível observar que as variações empregadas na execução de cada um dos furos conduzem a um caminho de melhoria nos resultados obtidos. Esta melhoria pode ser observada nos furos onde o alargador adotado apresentava menor diâmetro conduzindo a menores desvios na posição final do duto. Salientam-se também os benéficos resultados da execução dos furos verticais que conduziram a menores pressões no espaço anelar assim como possibilitaram medidas altimétricas diretas da posição do furo piloto. Desta forma, é provável que com um maior número de experimentos e incrementos tecnológicos se atinja o objetivo final, ou seja, executar redes de esgoto gravitacional com declividade constante e baixa. Em paralelo nas instalações executadas foram realizados testes para avaliação da precisão e acurácia do sistema de navegação responsável pelo fornecimento de informações de posição e temperatura da ferramenta de corte durante a execução do furo piloto. Este trabalho contempla ainda, a elaboração de uma nova solução para as instalações de esgoto executadas através do HDD. Esta solução propõe a aplicação de um esforço de tração a um elemento externo, uma geogrelha que envolve a tubulação, visando posicionar a mesma em declividade constante. Face a seu caráter inovador foram desenvolvidos equipamentos e procedimentos de ensaio de laboratório, para avaliar a aplicabilidade da solução na prática / The present work is focused on the horizontal directional drilling (HDD) method to install gravity sewers. The results of different techniques are described intending to meet the demands of gradient. Therefore, 4 experimental pilot bores were drilled simulating a section of those structures extending 30 m with HDPE pipelines of 125 mm external diameter. Those installations were engineered in the city of São Carlos, Brazil, in a clayey sand. For each of the 4 installations a distinct constructive process was adopted. Such characteristic was on account of the diameter of the selected reamer, the number of reamer steps and the vertical drills performed to relieve the pressure in the annular space, as well as the direct depth measurements of the pilot hole. After installing the pipes, altimetric measurements were performed inside them, hence enabling to quantitatively assess the obtained results. These results indicate the need to further refine the directional drilling technique for sanitary sewers. Yet it can be seen that the employed variations for each of the holes lead to an improved course of action with the observed results. Such improvement is perceived in the holes where the selected reamer had a smaller diameter, hence allowing for less displacement in the pipes final position. Also emphasized are the resulting benefits of the vertical drills that lead to less pressure in the annular space, as well as enabling altimetric measurements of the pilot hole position. Thus, it is presumed that with further experiments and technological developments the final objective is reached, meaning, putting into effect constant and low level gradient sewer networks. Tests for precision and accuracy assessment of the tracking system were also performed in each tube installed. The tracking system is responsible for providing information related to position and temperature of the drill head during the drilling operation. The steps for the development of a new HDD solution for sewer installation are presented. The idea is based on the application of a tensile force to an element external to the product, aiming at attaining a constant gradient. Equipments and procedures developed for this new technique are described.

The airflow field and particle trajectories inside hard disk drive (HDD) are investigated in this study using commercial software Fluent and Gambit. Three-dimensional grids inside the HDD configuration are built using Gambit taking into account all the components and their geometric details. The airflow field inside HDD is simulated using three incompressible Navier-Stokes equations for various disk rotational speeds. The effects of using the various turbulence models inside the Fluent software such as the standard k - ε , RNG k - ε and Reynolds Stress Method on the computed airflow characteristics are also assessed. Steady flow fields and the effects of rotational speeds are assessed. Based on the computed steady airflow patterns, particle trajectories are computed using routines available in Fluent as well as special particle trajectory functions defined by the user via the user-defined functions. Particles of different sizes and materials are injected at various locations in the computed flow field and the corresponding particle trajectories are studied. Based on the investigation, the trajectory tends to be different according to sizes and materials. The present work forms a basis for further investigation of heat transfer processes inside the HDD to address thermal management issues and also the computation of unsteady flow fields in the HDD due to the movement of the actuator arm during data storage and retrieval / Singapore-MIT Alliance (SMA)

Horizontal Directional Drilling (HDD) is used around the world when traditional open cut methods are not practical or impossible for installing pipelines. Maxi-sized drill rigs are the largest and most powerful directional drills and are more common in the field than ever before with over 5,000 rigs in operation world wide. The complexity of installations and the design associated with them continues to increase. This research has two main objectives. 1. Develop a real time data acquisition system for monitoring pullback forces on the product pipe; and, 2. Compare data gathered using maxi-sized drill rigs with current modelling methods using BoreAid. The first portion of the research, as listed above, required attaching multiple pressure transducers to the drilling display panel in an American Auger DD-1100 drill rig and recording, in real time, the carriage, rotation, and mud pressure as seen by the operator. This research also describes the various challenges and issues associated with developing real time in-the-bore data acquisition processes. Finally, future recommendations for further development of the in-the-bore data acquisition are discussed. The second portion of this research describes how the gathered data was processed into a workable data set. The field data was then compared to theoretical models by using the drill assistant tool BoreAid. The results of this comparison show that these models are appropriate for all size drill rigs, although some limitations are present.

Horizontal Directional Drilling (HDD) is used around the world when traditional open cut methods are not practical or impossible for installing pipelines. Maxi-sized drill rigs are the largest and most powerful directional drills and are more common in the field than ever before with over 5,000 rigs in operation world wide. The complexity of installations and the design associated with them continues to increase. This research has two main objectives. 1. Develop a real time data acquisition system for monitoring pullback forces on the product pipe; and, 2. Compare data gathered using maxi-sized drill rigs with current modelling methods using BoreAid. The first portion of the research, as listed above, required attaching multiple pressure transducers to the drilling display panel in an American Auger DD-1100 drill rig and recording, in real time, the carriage, rotation, and mud pressure as seen by the operator. This research also describes the various challenges and issues associated with developing real time in-the-bore data acquisition processes. Finally, future recommendations for further development of the in-the-bore data acquisition are discussed. The second portion of this research describes how the gathered data was processed into a workable data set. The field data was then compared to theoretical models by using the drill assistant tool BoreAid. The results of this comparison show that these models are appropriate for all size drill rigs, although some limitations are present.

Sedan företag började använda sig av internet som ett verktyg för sitt arbete har bekymmer uppstått som de inte haft tidigare, som hur företagsdata ska lagras, vad för utrustning som är bäst för deras behov. Genomförandet av arbetet delades in i tre delar, där det första var att ta reda på vilka olika datalagringslösningar som fanns och användes i servermiljöer. Detta gjordes via litteraturstudier. Den andra delen var att intervjua kundföretag om deras lagringslösningar samt intervjua leverantörer av datalagringslösningar med ett antal frågor som berörde deras datalagringlösning(ar), rekommendationer och framtidsutsikten för datalagring. Den tredje och slutgiltiga delen var att skriva samman analysen över den information som tillförskaffats och de iakttagelser som gjorts. Resultatet av intervjuerna visade på flera pålitliga och snabba alternativ för datalagring som kunder använde och leverantörer sålde.  Lösningar som användes och levererades var NAS(Network Attached Storage), molnlagring av data och SAN(Storage Area Network). Vid genomförande av analysen togs både intervjumaterialet och litteraturmaterialet i beaktning för att kunna komma fram till adekvata slutsatser. Syftet med slutsatserna var att kunna ge ett bra svar på de frågor i frågeställningen som låg till grund för examensarbetet. Vad man har kommit fram till är att det finns inget bra svar för vilken lösning är bäst utan att olika lösningar är anpassad till olika syften och behov.

The thesis aims at verification of using emerging Solid-State drives in disk arrays. The advent of SSD disks caused a small revolution in area of data storage, because the growth performance of hard drives has been slow compared to other PC components. But an entirely different principle of operation could mean compatibility problems between SSD and related technologies, such as RAID. This thesis aims at analyzing all the relevant technologies, mainly HDD, SSD and RAID. To achieve this objective, information from literature, articles and other appropriate sources will be used. Other objectives of this thesis are to determine how much are the SSDs suitable for use in the disk array, because low performance RAID controllers or different principles of operation could limit their efficiency. This question should be answered by submission of selected types of storage arrays to synthetic and practical tests of performance. The final goal is to use financial analysis of the test solutions as a shared file storage. Today, remote access to data is used by a wide range of job positions. Slow storage could mean inefficient use of working time and therefore unnecessary financial costs. The goal of my work is primarily to provide answers to the questions mentioned above. Currently it is very hard to find tests of more complex forms of disk arrays based on solid-state drives. This article can be also very useful for companies where fileservers are used to share user data. Based on the result of cost analysis, the company can then decide what type of storage is best for its purpose.