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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.
71

Finanční analýza podniků Mipexa s.r.o. a ČKD Nové Energo a.s. a jejich srovnání na základě dostupnosti dat / Comparison of the companies MIPEXA s.r.o. and ČKD Nové Energo a.s. from the perspective of financial analysis based on available data

Kratochvílová, Eva January 2010 (has links)
The aim of the present thesis is to compare the companies MIPEXA s.r.o. and ČKD Nové Energo a.s. from the perspective of financial analysis based on available data from 2006 to 2009. The thesis consists of two parts: theoretical and practical. In the first part, I describe financial analysis, namely its development, purpose, process, calculation of individual indicators and their informative values. In the practical part, based on calculated indicators, I attempt to compare and evaluate the development of the companies MIPEXA s.r.o. and ČKD Nové Energo a.s. and their reactions to external events. Both companies conduct business in the same field and have their headquarters in the Czech Republic; they differ in size and their financial possibilities.
72

Numerické simulace oscilačních procesů ve sluneční atmosféře se započtením zdrojových členů

JÍCHA, Jaroslav January 2019 (has links)
The aim of this thesis is to implement source terms to numerical model for curent sheet in solar atmosphere. The chapters are structured in the way that can present us with basic knowledge of the Sun and processes in its atmosphere. Than we present important equations for numerical solution and for the initial equilibrium of our simulation. One of the last chapters is dedicated to software we use for our numerical simulations called FLASH. In the end of the thesis we present results of our numerical simulations.
73

Photoacoustic experiments of metal sheets and silicon wafers.

January 1983 (has links)
Lau Shing-tat. / Chinese title: / Bibliography: leaves 129-130 / Thesis (M.Phil.)--Chinese University of Hong Kong, 1983
74

Patriotism, race, and gender bending through American song: cover illustrations of popular music from the Civil War to World War I

Hartvigsen, Kenneth 22 January 2016 (has links)
This dissertation engages America's illustrated sheet music through topical analyses of political and social ruptures from the Civil War to World War I. In so doing, it demonstrates that music illustrations fit into larger networks of American picture making, participating in the recording and redirecting of contemporary American anxieties. Chapter 1: Bloody Banner, Silent Drum: The Material Wounded on Civil War Sheet Music argues that violated flags and drums in music illustrations transcended their martial functionality to signify loss of innocence and life; in so doing, they took on their own subjectivity. Chapter 2: Banjos, Rifles, and Razors: Picturing American Blackness investigates the transition from black-face minstrel songs to the "coon song craze" of the 1880s and 1890s, arguing that the stock character's razor, a weapon frequently figured in the songs, was not only a symbol of violence but of white fears of black social mobility. Chapter 3: Hoopskirts and Handlebars: Gender Construction and Transgression in Victorian America offers two case studies, one of cross-dressing pictures after the Civil War, the other of gendered bicycle images, arguing that the American public between the war and the turn of the century enjoyed contemplating the flexibility of gender roles and boundaries. Chapter 4: "There Were Giants in the Earth": Monsters of the First World War argues that popular pictures of American giants and monstrous war machines engaged in symbolic battle with monstrous Huns, who symbolized German atrocity for a Euro-American public uncomfortable with the idea of war with European peoples. At the same time, giants represented the common belief of America's special role in international peace, as neutrality gave way to declared war. Sheet music illustration was a vibrant part of American visual culture. By assessing the layered meanings of these often ignored pictures, my dissertation seeks to recover and restore lost memories of America's usual but fraught visual romance with popular song.
75

The seismic vulnerability of sheet pile walls

McCullough, Nason J. 23 February 1998 (has links)
The seismic performance of port structures has been well documented following recent earthquakes, and indicates that port structures are highly susceptible to earthquake-induced damages. These damages are primarily due to soil liquefaction and the associated ground failures. Sheet pile bulkheads provide vital intermodal and lifeline transportation links between water-side and land-side traffic, and are waterfront structures particularly vulnerable to liquefaction-induced damages. Due to the prevalence of liquefaction-induced damages, many ports are utilizing soil improvement techniques to mitigate these hazards. Many port authorities have proposed utilizing performance-based design criteria to limit potential earthquake-induced damages. The current design method for sheet pile walls (Mononobe-Okabe) is based on simple, limit equilibrium analysis techniques, which are poorly suited for performance-based design. Recent advancements in the seismic design of sheet pile walls have addressed some of the limitations of the current design methods, but are still inadequate for performing a complete, performance-based design for locations that contain potentially liquefiable soils and/or where soil improvement strategies have been instituted. This study has focused on conducting an empirical investigation and numerical modeling to determine the seismic performance of sheet pile walls, and the performancebased benefit of soil improvement through densification. A case history validated, nonlinear effective stress computer program was used to perform numerical parametric studies on various design parameters (earthquake properties, depth of sheet pile embedment, sheet pile wall stiffness, tie rod length, density of the backfill, and extent of soil densification). The results have been presented as a performance-based design method, and include a design chart that provides practitioners with a preliminary design tool that may be used to estimate the seismic deformations of sheet pile walls with or without soil improvement. The study has demonstrated that soil densification can greatly reduce the seismicallyinduced deformations, especially when the magnitude of soil improvement extends beyond the location of the anchor. The study has also demonstrated that the use of soil densification techniques for mitigating seismic hazards may not be adequate in limiting deformations to allowable limits, and that other methods of soil improvement (cementation, drainage, etc.) or structural improvements may also be required. / Graduation date: 1998
76

Computational Ice Dynamics and Hydraulics : Towards a Coupling in the Ice Sheet Code ARCTIC-TARAH

Holmgren, Hanna January 2012 (has links)
Numerical ice sheet modeling is a rather young discipline: it started in the 1950s. The "first generation" models developed at that time are currently being replaced by "new generations" ones, such as e.g. ARCTIC-TARAH. ARCTIC-TARAH is a Bert Bolin Center for Climate Research spin-off from the Pennsylvania State University Ice sheet model (PSUI). When the Bolin Center received PSUI for subsequent independent development and adaption of the code to Arctic settings in 2010, an initial inspection of the source code suggested that PSUI also contained a module that allows for the treatment of glacial hydraulics. A numerical ice sheet model including coupling of ice dynamics and hydraulics is an extremely important tool in testing new hypotheses of former geological events. E.g., based on the recent finding that Arctic Ocean sediments contain a very distinct signature, it has been suggested that ice dammed lakes at the south-eastern margin of the late Weichselian Eurasian ice sheet drained into the Arctic Ocean in a catastrophic event around 55.000 years ago. The aim of this thesis is to perform a reconnaissance analysis of the glacio-hydraulic algorithms in ARCTIC-TARAH, as "inherited" (but never with published record of functionality) from PSUI. The work is carried out in two steps: first the routines and algorithms describing the hydraulics are located and explored, and then these routines are tested and verified by performing experiment simulations. The investigation of the program code reveals the presence of two hydraulics related modules in ARCTIC-TARAH. The main tasks of the module Water are to initiate lakes and oceans and to adjust hydrostatic pressure in each lake. Further, with the module Move Water activated, transportation of water (e.g. in rivers) is possible. Results from idealized experiment simulations verify the functionality of the routines in the module Water. An in-depth analysis of the module Move Water suggests that there is a mismatch in time units when solving the equations describing flow of water. Experiment simulations also support this flaw detected in the flow model. Preliminary adjustments were made to the source code  of the module Move Water, which made it possible to simulate the transportation of water both under an ice sheet and in rivers on land. However, these adjustments do not solve the problem of mismatching time scales, and the numerical solutions obtained from the experiments were observed to be unstable and, therefore, possibly incorrect. To be able to perform more advanced simulations in support of the above mentioned hypothesis, the flow model in the module Move Water needs to be improved or replaced. One solution to the problem with mismatching time scales, could be to use a so called multiscale solution in time.
77

Sheet Metal Forming Simulations with FEM

Lindberg, Filip January 2011 (has links)
The design of new forming tools get more problemtic as the geometries get more complicated and the materials less formable. The idea with this project is to evaluate if an implementation of a simulation software in the designing process, to simulate the forming process before actually building the tools, could help Duroc Tooling avoid expensive mistakes. To evaluate this, the commercial FEM simulation software LS-DYNA was used in a complicated project, where the design of the forming tools for forming a girder was considered. The main objective was to avoid cracking and severe wrinkling which may result in the forming process. With help of simulations a stable forming process which did not yield cracks or severe wrinkling, was eventually found. The girder was almost impossible to form without cracking, but the breakthrough came when we tried to simulate a preforming step which solved the problem. Without a simulation software this would never have been tested since it would be to risky and expensive to try an idea which could turn out to be of no use. The simulations also showed that the springback - shape deformation occuring after pressing - was large and hard to predict without simulations. Therefore, the tools were also finally springback compensated. We concluded that simulations are very effective to quickly test new ideas which may be necessary when designing the tools for forming complicated parts. Simulation also provided detailed quantitative information about the expected cracks, wrinkles, and weaknesses of the resulting pieces. Even though there is cost associated with simulations, it is obvious from this project that a simulation software is a must if Duroc Tooling wants to be a leading company in sheet metal forming tools, and stand ready for the higher demands on the products in the future.
78

The effect of the hydroxyl groups of cellulose on its papermaking properties

Bletzinger, J. C. (John Calvin) 01 January 1940 (has links)
No description available.
79

A study of the flocculation and dispersion of papermaking fibers

Erspamer, August 01 January 1939 (has links)
see pdf
80

Modeling and Analysis of Collaborative Product Development Process for the Sheet Metal Industry

Lien, Hsin-Huw 15 July 2003 (has links)
Abstract Currently there is not much study references related to product collaboration development model. In general only a concept of ideas or case study, but to be specific on detail steps of operating efficiency with best practice configuration, workplace, and management which is lack. So building a proper collaborative product development strategy reduces man-made mistakes and avoids process lateness will be a useful solution. Therefore, this research is focus on OEM business model of automobile press die industry in Taiwan. To investigate the new product development phase of the business models, including Proposal, Planning, R&D Design, Laboratory Pilot Run, Engineering Pilot Run, Production Pilot Run, Mass Productions. Also explore collaboration design process and simulations of the enterprise headquarter, customers and supplier. At the end, the research is use the ARIS modeling tool to establish OEM reference model of automobile press die, to bring a useful practical experiences as reference.

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