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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.
1

Modellgestütztes, auto-adaptives System für den klassifikationsbasierten Diagnoseprozess bei weitläufigen Inspektionsaufgaben /

Zöllner, Johann Marius. January 2006 (has links)
Univ., Diss.--Karlsruhe, 2005.
2

Beitrag zur differenzierten sicherheitstechnischen Bewertung und Gestaltung moderner Rohrfernleitungsanlagen auf der Grundlage eines spezifischen Risikokonzeptes

Przygodda, Jörg. January 2003 (has links) (PDF)
Halle, Wittenberg, Universiẗat, Diss., 2003.
3

Digital production pipelines: examining structures and methods in the computer effects industry

Bettis, Dane Edward 29 August 2005 (has links)
Computer animated films require collaboration: blending artistic concept with technical skill, meeting budget constraints and adhering to deadlines. The path which production follows from initial idea to finished product is known as the pipeline. The purpose of this thesis is to collect, study and share information regarding production pipeline practices and to derive a conceptual definition. Research focused on selected companies in the United States which have produced at least one feature-length computer generated film and continue to produce them. The key finding of this thesis is a conceptual definition of digital production pipelines: A digital production pipeline must, by definition, utilize digital computing hardware and software to facilitate human work and collaboration for the overarching purpose of producing content for film. The digital production pipeline is not a structure, but rather a malleable set of components which can be arranged, configured, and adapted into new structures as needed. These malleable components are human groups with assigned task domains, and digital hardware and software systems. The human groups are normally referred to as departments or teams. The digital hardware and software systems are operating systems, software tools and applications, networks, processors, and storage. The digital production pipeline is the synergy of these two types of components into adaptable systems and structures.
4

Ein transformativer Ansatz für die Synthese und Verifikation algorithmischer Hardwarebeschreibungen

Hinrichsen, Holger. January 2000 (has links) (PDF)
Darmstadt, Techn. Universiẗat, Diss., 2000.
5

Digital production pipelines: examining structures and methods in the computer effects industry

Bettis, Dane Edward 29 August 2005 (has links)
Computer animated films require collaboration: blending artistic concept with technical skill, meeting budget constraints and adhering to deadlines. The path which production follows from initial idea to finished product is known as the pipeline. The purpose of this thesis is to collect, study and share information regarding production pipeline practices and to derive a conceptual definition. Research focused on selected companies in the United States which have produced at least one feature-length computer generated film and continue to produce them. The key finding of this thesis is a conceptual definition of digital production pipelines: A digital production pipeline must, by definition, utilize digital computing hardware and software to facilitate human work and collaboration for the overarching purpose of producing content for film. The digital production pipeline is not a structure, but rather a malleable set of components which can be arranged, configured, and adapted into new structures as needed. These malleable components are human groups with assigned task domains, and digital hardware and software systems. The human groups are normally referred to as departments or teams. The digital hardware and software systems are operating systems, software tools and applications, networks, processors, and storage. The digital production pipeline is the synergy of these two types of components into adaptable systems and structures.
6

Mikrostrukturbasierte Zähigkeitsvorhersagen am Beispiel von Pipelinestählen /

Thönnessen, Florian. January 2009 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2009.
7

Analysis of oil-pipeline distribution of multiple products subject to delivery time-windows

Jittamai, Phongchai 12 April 2006 (has links)
This dissertation defines the operational problems of, and develops solution methodologies for, a distribution of multiple products into oil pipeline subject to delivery time-windows constraints. A multiple-product oil pipeline is a pipeline system composing of pipes, pumps, valves and storage facilities used to transport different types of liquids. Typically, products delivered by pipelines are petroleum of different grades moving either from production facilities to refineries or from refineries to distributors. Time-windows, which are generally used in logistics and scheduling areas, are incorporated in this study. The distribution of multiple products into oil pipeline subject to delivery time-windows is modeled as multicommodity network flow structure and mathematically formulated. The main focus of this dissertation is the investigation of operating issues and problem complexity of single-source pipeline problems and also providing solution methodology to compute input schedule that yields minimum total time violation from due delivery time-windows. The problem is proved to be NP-complete. The heuristic approach, a reversed-flow algorithm, is developed based on pipeline flow reversibility to compute input schedule for the pipeline problem. This algorithm is implemented in no longer than O(T*E) time. This dissertation also extends the study to examine some operating attributes and problem complexity of multiple-source pipelines. The multiple-source pipeline problem is also NP-complete. A heuristic algorithm modified from the one used in single-source pipeline problems is introduced. This algorithm can also be implemented in no longer than O(T*E) time. Computational results are presented for both methodologies on randomly generated problem sets. The computational experience indicates that reversed-flow algorithms provide good solutions in comparison with the optimal solutions. Only 25% of the problems tested were more than 30% greater than optimal values and approximately 40% of the tested problems were solved optimally by the algorithms.
8

Development of a framework for Integrated Oil and gas Pipeline Monitoring and Incident Mitigation System (IOPMIMS)

Johnson, Chukwuemeka Eze January 2017 (has links)
The problem of Third Party Interference (TPI) on Oil and Gas Pipelines is on the rise across the world. TPI is not only common in developing countries but is now occasionally experienced in developed countries including Germany and the UK. The risks posed by these third-party activities on Oil and Gas pipelines are enormous and could be measured in terms of financial costs, environmental damages as well as health and safety implications. The quest for an end to these malicious activities has triggered a lot of studies into the root causes of pipeline TPI, other causes of pipeline failure, risks associated with pipeline failure and their mitigation measures. However, despite the significance of the effects of TPI, very little has been done to proffer an enduring solution through research. This research therefore aims at developing a framework for integrated oil and gas pipeline monitoring and incident mitigation system through integration of various wireless sensors for effective monitoring of oil and gas pipelines. Having identified the existing gaps in literature as lack of reliable, accurate and standard method for oil and gas pipeline risk assessment model, the study undertook a quantitative approach to develop an effective Quantitative Risk Assessment (QRA) model for pipelines. The QRA model developed benchmarks pipeline risk assessment and gives the parameters with which standard QRA could be measured. The research findings indicate that risk associated with Nigerian Pipeline system is in the intolerable region whereas TPI is an increasing menace across the globe. Further findings show that Support Vector Machine (SVM) gave the best performance with 91.2% accuracy while Neural Networks (NN) and Decision Tree (DT) gave 63% and 57% accuracies respectively in terms of pipeline failure mode prediction accuracies. It was recommended that operators should draw out Pipeline Integrity Management (PIM) programs and store pipeline data in a format that captures number of fatalities, property damages and costs as well as volume of oil or gas spilled to ensure that accurate data is obtainable for improved PIM. In conclusion, having achieved its aim and objectives evidenced by the framework, model developed, and the recommendations presented, the research has contributed in no small measure to providing a solution to pipeline incidences.
9

Assessment of Crack in Corrosion Defects in Natural Gas Transmission Pipelines

Hosseini, Seyed Aliakbar 26 April 2010 (has links)
Pipelines are one of the safest forms of transportation for oil and gas. However, pipelines may experience some defects, such as cracks, corrosion and cracks in corrosion, during service period. In this thesis, the current defect assessment methods for crack, corrosion and crack in corrosion defects are reviewed. The aim of this study was to evaluate the effect of the crack in corrosion defects on the failure pressure of natural gas transmission pipelines. Consequently, a series of burst tests with varying defect depths were undertaken on end-capped, seam-welded API 5L Grade X60 (433 MPa yield stress) pipeline steel of external diameter 508 mm (20 inch), 5.7 mm wall thickness. Defects were created by pre-fatiguing the pipe to create a crack. The number of cycles required to create a fatigue crack were varied between 75000 to 150000 cycles based on the desired final defect depth. For the (CIC) defects, the pipe was pre-fatigued to create a sharp crack, and the artificial corrosion defect was simulated by machining a rectangular groove over the fatigue crack. The rupture tests were conducted by pressurizing the pipe until failure occurred. Results were analyzed using various assessment methods. For the artificial corrosion defects, the predicted failure pressures based on RSTRENG were more reliable than those based on Modified B31G. This study revealed that CorLAS provided the least conservative prediction for crack defects, whereas the other methods provided more conservative estimates of failure pressure. Moreover, the predicted failure pressure of the level 3 FAD for API 579 cylinder equations had better agreement with experimental results in comparison with the other methods, i.e. BS7910 and NG-18. The failure pressure for CIC defects for pipes tested fell between corrosion defects (lower bound) and crack defects (upper bound). The transition to crack defect behavior only occurs when the crack defect depth is significant or vice versa. It should be noted that the crack to corrosion ratio is not the only parameter to evaluate a CIC defect. There are other parameters such as total defect depth and defect profile, which affect the failure behavior of a CIC defect.
10

A Comparative Analysis on Sewer Structural Condition Grading Systems Using Four Sewer Condition Assessment Protocols

Khazraeializadeh,Soroush Unknown Date
No description available.

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