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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.
721

IMPLEMENTATION OF A CLOUD SHELL FOR LIGHT-WEIGHT UNIX PROGRAMMABILITY SUPPORT IN A DISTRIBUTED CLOUD ENVIRONMENT

Wei, Tzu-Chieh 09 February 2012 (has links)
This thesis describes the implementation of a UNIX-styled shell environment for cloud systems. This new scripting language, the cloud shell (CLSH), uses a syntax based upon the familiar BASH shell of UNIX systems. This familiar syntax allows users to quickly learn the new environment. The difference, as compared to BASH, is that CLSH gives the user easy access to the parallelism of the cloud. Indeed, the user does not need to explicitly refer to the cloud at all; the cloud becomes simply a virtual file system and the user experience is quite similar to standard bash programming. This cloud shell is built into Hadoop¡¦s HDFS file system. The difference, as compared to HDFS, is that CLSH offers a full range of UNIX-style commands, rather than a small subset of simple commands. Moreover, CLSH is a full-fledged scripting language that offers much more control over file management than does HDFS. To achieve comparable behavior within HDFS, the user must use either the Pig Latin tool or else use java scripting. Not only are these alternatives harder to use than CLSH, but they also perform slower and are incapable of performing certain tasks that CLSH can easily achieve. Moreover, the cloud shell environment simply provides the user with a better cloud interface; it does not preclude the use of Pig Latin or Java scripts.
722

Study on Architecture-Oriented Enterprise Private Cloud Model

Hsu, Chine-chuan 12 June 2012 (has links)
Cloud computing has updated the appearance of the Information Technology (IT) infrastructure, and in addition to lower operation costs provides real-time services and reduces the information service barrier. In order to adapt to the rapidly changing market demand, enterprises are beginning to consider the feasibility of the deployment of cloud computing. The business environment changes so fast that an integrated dynamic framework and intelligent service system to achieve enterprises¡¦ visions, objectives and strategies, and to quick response is needed. Regarding to the three main service types of cloud computing: Software as a Service (SaaS), Platform as a Service (PaaS), Infrastructure as a Service (IaaS), this study proposes an integration model for enterprise administration. Cloud computing packs the functionality of dynamic resource adjustment. From the deployment of organizations to the customer interactions, cloud computing is divided into a public cloud, private cloud and mixed cloud based on its deployment model. As for the private cloud, its information security and efficiency allow enterprises execute their operations smoothly according to the business rules. Thus more and more enterprises are inclined to deploy private clouds. This study uses structure-behavior coalescence architecture description language (SBC-ADL) to accomplish the systems architecture, and provides thorough suggestions of dynamic resources allocation as a reference model for any enterprise which plans to deploy the cloud computing service. For those enterprises that have already implemented cloud computing services, the systems architecture can be referred to better their business management. Describing the relationship between the various systems architecture is helpful in quickly understanding the system operation. Consider reducing misunderstanding and increasing work efficiency and information correctness, SBC-ADL works very well as an effective tool for training and communication within the IT department.
723

Design and Implementation of Cloud Data Backup System with Load Balance Strategy

Tsai, Chia-ping 15 August 2012 (has links)
The fast growing bandwidth has made the development of cloud storage. More and more resource has put in cloud storage. In this thesis, we proposed a new cloud storage that consists of a single main server and multiple data servers. The main server controls system-wide activities such as data server management. It also periodically communicates with each data server and collects its state. Data servers store data on local disks as Windows files. In order to response to the large number of data access, Selection of the server which is necessary to offer equalized performance. In this paper, we propose a server selection algorithm using different parameters to get the performance metrics which enables us to balance multi-resource from server-side. We design new cloud storage and implement the algorithm. According to upload experiment, the difference between the maximum and the minimum free space when using our algorithm is less than 5GB. But using the random mode, the free space difference is increased as time, and the maximum is 30GB. In the mixed experiment, we added the download mode, and our algorithm is fewer than 10GB. The result of the random mode approximated to the first experiment. Finally, our algorithm obtains 10% and 3% speedup in upload throughput by upload experiment and mixed experiment, 10% speedup in download throughput by mixed experiment.
724

The Design of Cloud-Economical Computing Services for Program Trading

Hsu, Chi-Shin 26 August 2012 (has links)
Program Trading has gotten more popular recent years. According to thestatistics, there was about 53.6% of daily volume in the United States, and increased to 73% in 2009. With the universal of program trading, more people have begun to research program trading. The purpose of this paper is constructing a developed platform of program trading for researching or developing. In addition to developed platform, we provide the run-time environment, and three main functions: 1. The job scheduler 2. The high scalability 3. The developed platform In this paper, we use SLURM to implement an economical computing service for program trading. SLURM is a resource management software for some large clusters. However it lacked for an easy interface to the ended users. We modify Xinetd as the external interface for SLURM, and implement the program trading development platform for researching or developing. According to the result, using our scheduler and the external interface that modify from Xinetd can be effective in controlling the server resource and increase the availability.
725

3D Map Construction and Data Analysis by LiDAR for Vehicles

Tai, Chia-Hui 03 September 2012 (has links)
Nowadays, LiDAR(Light Detection And Ranging, LiDAR) is the more important and widely applicable measurement technique. The rise of visual system in 3D is very useful to the measurement of LiDAR and gets more importance value for 3D reconstruction technology, in which abundant surface features are implied in the point cloud data. Combined with the image and laser technique for real-time rendering, the LiDAR will be more functional. This thesis proposes and designs a system which combined with Laser Range Finder and 3D visual interface for vehicles, and also equipped with rotary encoder and initial measurement unit to DR(Dead Reckoning) function. Through the coordinate transform method of 2D to 3D, the 3D coordinate of each point will be calculated, and embedded with the color information which captured from the camera to take 3D color point cloud collection. This method is also called Mobile Mapping System(MMS). In addition, this mapping system uses Direct Memory Access technology to display the point cloud synchronous in 3D visual system. Except for the point cloud collection, the reconstruction of point cloud data is used in this system. The surface reconstruction is based on Nearest Neighbor Interpolation method. There are two factors to conduct the interpolation process: the angle and distance between two sample points from the points sequence. The reconstruction of point cloud and calibration of DR is not only to confirm the accuracy of 3D point cloud map but also the ¡§New Geography¡¨ of the 3D electronic map. This research will build up an independent Mobile Mapping System.
726

Applying MapReduce Island-based Genetic Algorithm-Particle Swarm Optimization to the inference of large Gene Regulatory Network in Cloud Computing environment

Huang, Wei-Jhe 13 September 2012 (has links)
The construction of Gene Regulatory Networks (GRNs) is one of the most important issues in systems biology. To infer a large-scale GRN with a nonlinear mathematical model, researchers need to encounter the time-consuming problem due to the large number of network parameters involved. In recent years, the cloud computing technique has been widely used to solve large-scale problems. Among others, Hadoop is currently the most well-known and reliable cloud computing framework, which allows users to analyze large amount of data in a distributed environment (i.e., MapReduce). It also supports data backup and data recovery mechanisms. This study proposes an Island-based GAPSO algorithm under the Hadoop cloud computing environment to infer large-scale GRNs. GAPSO exploited the position and velocity functions of PSO, and integrated the operations of Genetic Algorithm. This approach is often used to derive the optimal solution in nonlinear mathematical models. Several sets of experiments have been conducted, in which the number of network nodes varied from 50 to 125. The experiments were executed in the Hadoop distributed environment with 10, 20, and 26 computers, respectively. In the experiments of inferring the network with 125 gene nodes on the largest Hadoop cluster (i.e. 26 computers), the proposed framework performed up to 9.7 times faster than the stand-alone computer. It means that our work can successfully reduce 90% of the computation time in a single experimental run.
727

Cloud Computing Evaluation : How it Differs to Traditional IT Outsourcing

Brunzel, Tino, Di Giacomo, Débora January 2010 (has links)
<p><strong>Introduction</strong></p><p>Cloud Computing, that is providing computer resources as a service, is a technology revolution offering flexible IT usage in a cost efficient and pay-per-use way. As for the evaluation of companies to whether which technology solution to use, it would be necessary to decide whether or not the evaluation of cloud computing would actually differ to the traditional way of IT outsourcing.</p><p><strong></strong><strong>Problem Discussion</strong></p><p>Outsourcing IT capabilities are a crucial and inevitable step for enterprises that want to survive in the currently high competitive climate. Until now most of the researches, that has been done so far, only consider the XaaS model only from a traditional IT outsourcing point of view rather than in the cloud computing context. This research will now include the evaluation of cloud solutions giving companies another possibility to outsource their IT resources.</p><p><strong></strong><strong>Purpose</strong></p><p><strong></strong>The purpose is now to see how the evaluation of cloud computing possibilities as an outsourcing option actually differs to traditional IT outsourcing. One aspect that needs to be covered with this purpose, is whether it is possible to evaluate the source through a cloud computing solution with the same concepts and theories used to evaluate traditional IT outsourcing. It will also be the purpose to see, which aspects need to be added or removed when considering a cloud computing opportunity compared to the traditional IT outsourcing.</p><p><strong></strong><strong>Method </strong></p><p>With help of the theoretical framework, interviews have been launched with three companies to see what their general opinion and knowledge is on the evaluation of cloud computing and its maturity. Questions have been asked openly so that answers could not be directed or manipulated by the authors of the research.</p><p><strong></strong><strong>Conclusion</strong></p><p>After challenging the theoretical framework against the data collected, the traditional IT outsourcing theories appeared to be valid also for the evaluation of cloud computing solutions. Some important concepts are added to the evaluation of cloud computing solutions in consequence of particularities present in the model.</p>
728

Planning and Optimization During the Life-Cycle of Service Level Agreements for Cloud Computing

Lu, Kuan 16 February 2015 (has links)
Ein Service Level Agreement (SLA) ist ein elektronischer Vertrag zwischen dem Kunden und dem Anbieter eines Services. Die beteiligten Partner kl aren ihre Erwartungen und Verp ichtungen in Bezug auf den Dienst und dessen Qualit at. SLAs werden bereits f ur die Beschreibung von Cloud-Computing-Diensten eingesetzt. Der Diensteanbieter stellt sicher, dass die Dienstqualit at erf ullt wird und mit den Anforderungen des Kunden bis zum Ende der vereinbarten Laufzeit ubereinstimmt. Die Durchf uhrung der SLAs erfordert einen erheblichen Aufwand, um Autonomie, Wirtschaftlichkeit und E zienz zu erreichen. Der gegenw artige Stand der Technik im SLA-Management begegnet Herausforderungen wie SLA-Darstellung f ur Cloud- Dienste, gesch aftsbezogene SLA-Optimierungen, Dienste-Outsourcing und Ressourcenmanagement. Diese Gebiete scha en zentrale und aktuelle Forschungsthemen. Das Management von SLAs in unterschiedlichen Phasen w ahrend ihrer Laufzeit erfordert eine daf ur entwickelte Methodik. Dadurch wird die Realisierung von Cloud SLAManagement vereinfacht. Ich pr asentiere ein breit gef achertes Modell im SLA-Laufzeitmanagement, das die genannten Herausforderungen adressiert. Diese Herangehensweise erm oglicht eine automatische Dienstemodellierung, sowie Aushandlung, Bereitstellung und Monitoring von SLAs. W ahrend der Erstellungsphase skizziere ich, wie die Modellierungsstrukturen verbessert und vereinfacht werden k onnen. Ein weiteres Ziel von meinem Ansatz ist die Minimierung von Implementierungs- und Outsourcingkosten zugunsten von Wettbewerbsf ahigkeit. In der SLA-Monitoringphase entwickle ich Strategien f ur die Auswahl und Zuweisung von virtuellen Cloud Ressourcen in Migrationsphasen. Anschlie end pr ufe ich mittels Monitoring eine gr o ere Zusammenstellung von SLAs, ob die vereinbarten Fehlertoleranzen eingehalten werden. Die vorliegende Arbeit leistet einen Beitrag zu einem Entwurf der GWDG und deren wissenschaftlichen Communities. Die Forschung, die zu dieser Doktorarbeit gef uhrt hat, wurde als Teil von dem SLA@SOI EU/FP7 integriertem Projekt durchgef uhrt (contract No. 216556).
729

The Solubility of Triton X-114 and Tergitol 15-S-9 in High-Pressure Carbon Dioxide Solutions

Smeltzer, Brandon 08 December 2005 (has links)
In the sol gel production of high surface area catalyst, the template, a surfactant, is the key component of the process. A template too soluble in the supercritical dryingextraction process can yield a catalyst with a lower surface area. A template completely insoluble in the supercritical drying-extraction process can lead to a longer calcinations step and lower catalyst surface area. Template recovery also enhances the economic feasibility of plant scale production of high surface area catalyst. For these reasons knowing surfactant solubility in supercritical media is important. The solubility of surfactants tert-octylphenoxypolyethoxyethanol (commercially available and hereafter referred to as Triton X-114) and alkyloxypolyethyleneoxyethanol (commercially available and hereafter referred to as Tergitol 15-S-9) in supercritical carbon dioxide and ethanol entrainer have been determined at five-degree increments from 35 oC to 50oC. The solubility of the surfactants was determined by charging a variable volume cloud point system with the entrainer-surfactant mixture followed by liquid carbon dioxide. With the resulting stirred homogeneous mixture heated to temperature, cloud point pressures were observed as the phase analyzer cell was pressurized by adjusting the variable volume. An average of five values for cloud point pressure is reported here. The mixture behaviors were modeled using the Improved Rackett equation and the Peng-Robinson-Stryjek-Vera (PRSV) equation of state with Wong-Sandler (WS) mixing rules. For the Carbon Dioxide (CO 2) (1) – Ethanol/Triton X-114 (2) mixtures studied, compositions ranged from 93.2 mol% CO 2 to 97.7 mol% CO2. The solubility of Triton X-114 ranged from 0.02 mol% to 0.05 mol% at temperatures ranging from 35 oC to 50oC. Cloud point pressures observed for this system range from 95 bar to 143 bar. For the CO 2 (1) – Ethanol/Tergitol 15-S-9 (2) mixtures studied, compositions ranged from 92.3 mol% CO 2 to 94.4 mol % CO2. The solubility of Tergitol 15-S-9 ranged from 0.02 mol% to 0.03mol% at temperatures ranging from 35 oC to 50oC. Cloud point pressures observed for this system range from 89 to 154 bar.
730

Engineering collaboration via electronic media : how to promote reflective thinking skills and visualize data with technology / How to promote reflective thinking skills and visualize data with technology

Ramos, Noel Hector 27 February 2012 (has links)
Online discussion forums and reflective writing are proven methods for enriching conceptual understanding and are hallmarks of engineering education. Plagiarism and many students’ apprehension to contribute to online journals can plague the effectiveness of these educational tools. Using elements of the engineering design cycle, I have created a blogging website that addresses these problems by restricting comment visibilities for users and includes a graphic visualization called a “word cloud” to supplement discussion. A prototype was tested with UTeach Engineering teachers for feedback on design and use. The critiques provided examples of classroom use, constructive design feedback, and ideas for its use as a formative assessment. The design could be used as a pedagogical tool for an investigation of formative assessments in engineering education, but further research for “word cloud” visualizations and journal data collection is needed to expand the current design. / text

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