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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.
101

Podnikatelský plán / Business Plan

Smutný, Nikola January 2011 (has links)
Master’s thesis considers development of other company business activities with the focus on the profit of the whole plan. The first part of the thesis concentrates on the theoretical recourse for the creation of the business plan, definition of basic procedures making the business plan. The second part of the thesis analyses branch in which the plan will be realized. The third part of the thesis suggests real solution, prediction of sales, profits and recoverability of investment.
102

Identifying subarctic river thermal and mechanical ice break-up using seismic sensing

Ursica, Stefania January 2021 (has links)
River-ice break-up in high-latitude regions, despite its brevity, is a fundamental process, representing the most dynamic and complex period of fluvial processes. Moreover, ice break-up has significant cascading ecological effects, with a different severity for mechanical vs. thermal break-up, and thus, motivates the importance of monitoring efforts. Classical research methods, such as fieldwork or analysis of photographs and aerial imagery, offer a general perspective on the timing of ice break-up but have safety and logistic issues caused by the dangers of unstable ice cover, the lag times between event occurrence and observation, and the frequent low visibilities. The emerging field of environmental seismology, which studies surface processes through seismic signals, provides an alternative solution to these shortcomings by continuously recording high temporal resolution data. Seismic sensing can potentially record any event within a set distance if the produced signal is powerful enough. Three geophones had monitored the subarctic Sävar River reach for 185 days to test the efficiency of seismic methods to capture ice-cracking events, and based on their characteristics, to identify thermal vs. mechanical ice break-up. With visual and multivariate analysis, seismic methods provided a conservative set of 2 228 events, detected at milliseconds precision, described, and located. Besides, both trigger lag times and principal component analysis depicted correlations between environmental drivers and ice-cracking events. The automatic picker based on duration and trigger thresholds required manual supervision because of the initial numerous false signals that accounted for 96% of total initial events. Ice-cracking signals as short as 0.2s and frequencies of 8-40 Hz with an average power of -117 dB were statistically defined, classified, and described by case events as two types, associated, based on their spectral and temporal patterns, with the two ice break-up modes. With an estimated Rayleigh wave velocity of 680 m/s, all ice-cracking signals' locations were within the instrumented area. Trigger lag times analysis improved detection and showed a strong link between ice-cracking events and drivers of lag times less than three hours, including near-immediate responses (< 2s). With multivariate analysis, the lag times showed a mainly climatic control for thermal melting and a primarily fluvial control in mechanical ice break-up. The combination of statistical and seismic analysis provides, despite the considerable manual screening, a valid and potentially site-transferable method to extract and describe ice-cracking signals and thus identify ice break-up modes in northern rivers.
103

A study on Extraction of Natural Cities from the Nightlight Imagery Using Head/tail breaks method

Wu, Sirui January 2013 (has links)
With the high development of economic and demand for city research, an issue of detecting city boundaries plays an extremely important role in urbanization that promotes the progress of human civilization. Some critical applications such as land use, urban planning and city sprawl have been constantly discussed, which rely on the acquisition of city areas. For the better acquisition of city areas, choosing a proper method to capture city boundaries becomes significant where it greatly improves the value of city study. Although conventional data can be used to define the city boundaries, some drawbacks still exist when measuring the city boundaries in a global scale. Remote sensing (RS) data of nightlight imagery (2010) by Defense Meteorological Satellite Program’s Operational Linescan System (DMSP/OLS) acquired from National oceanic and atmospheric administration's National Geoscience Data Center (NOAA/NOGA) is applied to extract the city boundaries in fifty countries, of which these countries are chosen followed by the Gross Domestic Product that are ranked in top 50. In this case, the data distribution of nightlight imagery followed by heavy-tailed distribution. Head/tail break algorithm poses a possibility of calculating reasonable threshold and extracting the natural cities with the help of software based on the Geomatics information system (GIS). An extended study of power law is made by using of power law estimator from previous studies to check whether the extracted natural cities can match the power law distribution. Result shows that combination of the nightlight imagery data and the head/tail break is capable of extracting the city boundaries and a set of possible thresholds with visual inspection by using the head/tail break are executed. There is only one country, namely Belgium, cannot be processed due to its data properties. Result also address how well the natural cities of the fifty countries can be extracted in terms of visual inspection, among the chosen cities, 33 of countries boundaries can be better matched and 13 countries can fundamentally match the city boundaries. Meanwhile, an extended study of power law is provided and four countries have to be found that do not follow the power law distribution. From the result obtained, the study expects that integration of support data will efficiently increase the accuracy of extraction and more useful information can be acquired in further study. On the other hand, a comparative study of threshold decision needs to be verified, put it differently, whether using head/tail break with visual inspection on extracted city boundaries is helpful or not.
104

Feasibility of diesel-electric hybrid drives for combine harvesters

Good, Grant January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Jason Bergtold / Efficiency and technology are increasingly important selling points for combine harvesters. Diesel-electric hybrid drives have taken hold in the construction equipment industry, and are providing marketable efficiency benefits for some heavy equipment customers. This thesis explores the technical and economic feasibility of utilizing diesel-electric hybrid drives on AGCO combine harvesters. To determine the technical feasibility of utilizing diesel-electric hybrid drives on AGCO combine harvesters, a search was conducted for prior literature relating to the use of electric drives on other heavy, off-highway equipment. This information, coupled with data provided by experts in the field, was used to determine if electric drives could fulfill the unique requirements of combine harvesters, and be practically utilized for this application. To determine the economic feasibility of utilizing diesel-electric hybrid drives on AGCO combine harvesters, an optimization model was constructed to seek out the most economically viable configuration of electric drives for this application. The model takes in to consideration the different use-cases in which this equipment is expected to perform, as well as the component costs and operating efficiencies of both the drives in place currently and the proposed electric drives. The outcome of the model was then utilized to compare the best-case configuration to the minimum requirement for economic feasibility. The technical feasibility assessment conducted for this thesis led to the conclusion that it would be technically feasible to utilize electric drives on a combine harvester. There are commercially available electric drive components which are suitable for use in the environment that this equipment is expected to operate in, and a prototype combine harvester having electric drives has previously been constructed. The economic feasibility assessment conducted for this thesis revealed that it is not economically feasible to utilize electric drives on AGCO combine harvesters at this time. Under the current circumstances, the most economically viable configuration would take nearly twice the machine’s usable operating life to provide a benefit to a customer from fuel savings. Sensitivity analysis revealed that significant changes in the price of fuel or electric drive components would be necessary to change the outcome of this study.
105

Mad2l2 as a safeguard for open chromatin in embryonic stem cells

Rahjouei, Ali 13 June 2016 (has links)
No description available.
106

Maten på jobbet : arbetsmåltider och uppfattningar om arbetsmåltider hos personal i roterande 3-skift vid en processindustri

Mustonen Ljung, Marie January 2016 (has links)
I dagens samhälle är vi aktiva dygnet runt både gällande fritid och arbete. Detta innebär att det måste finnas tillgänglig arbetskraft under dygnets alla timmar, vilket medför stor påfrestning på arbetstagares biologiska dygnsrytm. De oregelbundna arbetstiderna kan inverka negativt på arbetstagarens både fysiska och psykiska hälsa. Företag kan tillsammans med lokala fackföreningar förhandla bort den lagstadgade matrasten och ersatta den med ett måltidsuppehåll vilket innebär att det ingår i arbetstiden och får nyttjas i mån av tid. Syftet med denna studie var att kartlägga de uppfattningar som arbetstagare i roterande 3-skift vid en processindustri har om måltidsuppehållet, var och när deras måltidsuppehåll tar plats och vad de äter och dricker. 15 skiftarbetare har under 6 arbetsskift vardera, fotodokumenterat vad deras födointag under måltidsuppehåll bestod av. Dessa kategoriserades genom Food-based Classification of Eating Episodes. Fotografierna visade att totala antalet ät-tillfällen var lägre under nattskiftet i jämförelse med andra skift. Skiftarbetarna intervjuades och deras utsagor genomgick en fenomenografisk analys där det framkom att deras uppfattningar om måltidsuppehållet är att det är en social tillställning som stärker gruppgemenskapen. När arbetstagarna äter en måltid sitter de oftast vid matbordet och då ”ställer man upp för varandra” så att måltiden skall kunna slutföras. Om det gäller ett mellanmål kan intaget ske vid arbetsplatsen och om något händer får de bryta och arbeta. Vidare studier behövs för att verifiera uppfattningar i andra arbetsgrupper. / In today´s society, we are active day and nights, both in leisure time and at work. This means that employees must be available at work 24-hours a day which inflict high strain on their circadian rhythms. The irregular working hours can affect negatively on the employee’s physical and mental health. Companies can, together with local unions, negotiate away the statutory dinner break and replace it with meal break, which means that it is included in working hours and should be used as time permits. The purpose of this study was to identify the perceptions of workers in rotating 3-shift, in a process industry, when and where their meal breaks take place and what they ate. 15 shift workers have during 6 shifts each, photo-documented what their meal breaks consisted of. Consumption of foods and beverages were categorized by Food-Based Classification of Eating Episodes. The photographs showed that the number of eating occasions was lower during the night shift in comparison to other shifts. Shift workers were interviewed and their statements underwent a phenomenographical analysis which revealed that their perception of the meal break is a social event as well that strengthens the group community. When the workers were having a meal, it is mostly occurred at the dinner table. The shift workers replaced each other so each one had the possibility to take a meal break. Regarding snack intakes, it could occur at their workplace and if something happened in the process, they could immediately return to work. Further studies are needed to verify the perceptions of other working groups.
107

Evaluation of drop break-up after impingement on horizontal slat grids and the effect of drop size of cooling tower rain zone performance

Terblanche, Riaan 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Natural draught wet-cooling tower rain zone performance can be significantly enhanced by reducing the mean drop size in the rain zone with the installation of specially designed grids below the cooling tower fill. Drops enter the rain zone in the form of a polydisperse drop distribution, dripping from below the cooling tower fill, comprising relatively large drops. In order to design and optimize a grid for breaking up these drops, the mechanisms of drop break-up after impingement on the grid surface, referred to as splashing, straddling and dripping, need to be clearly understood. Two of these mechanisms, splashing and straddling, are therefore investigated experimentally using high speed video cameras to measure initial drop sizes, mass fractions and drop size distributions after impingement on different horizontal slats covered with a thin layer of water. The following parameters are varied independently for these experiments: drop fall distance, initial drop size, slat width and the water film thickness on the slats. Dripping from below the grid, is investigated theoretically. The effect of drop interaction on the drop size distribution in the rain zone is also investigated experimentally by measuring the drop distributions at the top and bottom of rain zones with a height of approximately 7.05 m to 7.65 m for different inlet distributions. The experimental drop break-up data, numerically obtained splash drop trajectory data and drop interaction data found in literature are used to develop a theoretical model of a purely counter flow cooling tower rain zone with and without installed grids. The model is compared to experimental data and theoretical data from literature and the predicted thermal and dynamic behaviour of the rain zone are generally found to be in good agreement with these results. Ultimately, this model is used for the optimization of the grid layout in terms of variables such as distance between the grid and the fill, slat width, slat spacing and slat height. It is found that the best drop break-up is achieved for grids comprising narrower slats with lower grid porosities as opposed to grids comprising wider slats. For the determined optimal grid layout it is found that a significant improvement in cooling tower performance can be achieved. / AFRIKAANSE OPSOMMING: Nat-koeltoringreënsonevermoë kan aansienlik verhoog word deur die druppelgrootte in hierdie gebied te verklein deur roosters, wat spesifiek vir hierdie doel ontwerp is, onder die pakkingsmateriaal te installeer. Die inlaatdruppelverdeling aan die bokant van die reënsone bestaan uit ‘n verdeling van relatief groot druppels wat drip van die onderkant van die pakkingsmateriaal. Ten einde ‘n rooster te ontwerp en te optimeer wat hierdie druppels kan opbreek moet die meganismes van druppelopbreking, bekend as spatting, vurking en drip goed verstaan word. Spatting en vurking is om hierdie rede eksperimenteel ondersoek, met behulp van hoëspoed videokameras. Die volgende veranderlikes is onafhanklik verander tydens hierdie eksperimente: valafstand van die druppel, aanvanklike druppelgrootte, latwydte en die dikte van die lagie water bo-op die lat. Die dripmeganisme aan die onderkant van die rooster is slegs teoreties ondersoek. Die effek wat druppelinteraksie in die reënsone het op die druppelgrootte is ondersoek deur die druppelgroottes aan die bo- en onderkant van ‘n 7.05 m tot 7.65 m reënsone te meet vir verskillende druppelinlaatverdelings. Die eksperimentele druppeldata, sowel as numeries berekende data wat die snelheid en trajek van spatdruppels beskryf, tesame met data vir druppelinteraksies wat uit die literatuur verkry is word gebruik om ‘n teoretiese model te ontwikkel vir ‘n suiwer teenvloei koeltoringreënsone met en sonder roosters. Hierdie model word vergelyk met eksperimentele data en data wat uit die literatuur verkry is en daar is gevind dat daar oor die algemeen ‘n goeie ooreenstemming is tussen die voorspelde en gemete termiese en dinamiese gedrag van die reënsone. Uiteindelik word die model gebruik vir die optimering van die rooster in terme van die volgende veranderlikes: afstand tussen rooster en pakkingsmateriaal, latwydte, latspasiëring en lathoogte. Daar word gevind dat beter druppelopbreking verkry word deur gebruik te maak van smaller latte en ‘n laer roosterporeusiteit. Daar is gevind dat die bepaalde optimale roosteruitleg in die reënsone van ‘n koeltoring ‘n wesenlike verbetering in koeltoringvermoë tot gevolg kan hê.
108

An application of financial theory in break-even analysis and financial project monitoring of a high-speed novel ferry in the HongKong and Macao service

Lee, Yip-Chuen, Anthony., 李業全. January 1982 (has links)
published_or_final_version / Business Administration / Master / Master of Business Administration
109

Understanding the mechanisms underlying DSB repair-induced mutagenesis at distant loci in yeast

Saini, Natalie 22 May 2014 (has links)
Increased mutagenesis is a hallmark of cancers. On the other hand, this can trigger the generation of polymorphisms and lead to evolution. Lately, it has become clear that one of the major sources of increased mutation rates in the genome is chromosomal break formation and repair. A variety of factors can contribute to the generation of breaks in the genome. A paradoxical source of breaks is the sequence composition of the genomic DNA itself. Eukaryotic and prokaryotic genomes contain sequence motifs capable of adopting secondary structures often found to be potent inducers of double strand breaks culminating into rearrangements. These regions are therefore termed fragile sequence motifs. Here, we demonstrate that in addition to being responsible for triggering chromosomal rearrangements, inverted repeats and GAA/TTC repeats are also potent sources of mutagenesis. Repeat-induced mutagenesis extends up to 8 kb on either side of the break point. Remarkably, error-prone repair of the break by Polζ reconstitutes the repeats making them a long term source of mutagenesis. Despite its negative connotations for genome stability, the mechanisms underlying the unstable nature of double strand break repair pathways are not known. Previous studies have demonstrated that break induced replication (BIR), a mechanism employed to repair broken chromosomes with only one repairable end, is highly mutagenic, undergoes frequent template switching and often yields half-crossovers. In the work presented here, we show that the instabilities inherent to BIR can be attributed to its unusual mode of synthesis. We determined that BIR proceeds via a migrating bubble with long stretches of single-stranded DNA and culminates with conservative inheritance of the newly synthesized DNA. We propose that the mechanisms described here might be important for generation of repair-associated mutagenesis in higher organisms. Secondary structure forming repeats like inverted repeats have been found to be enriched in cancer cells. These motifs often constitute chromosomal rearrangement hot-spots and demonstrate the phenomenon of kataegis. This study provides a mechanistic insight into how such breakage-prone motifs contribute to hypermutability of cancer genomes.
110

Numerical Modeling of Tsunami-induced Hydrodynamic Forces on Free-standing Structures Using the SPH Method

St-Germain, Philippe 23 November 2012 (has links)
Tsunamis are among the most terrifying and complex physical phenomena potentially affecting almost all coastal regions of the Earth. Tsunami waves propagate in the ocean over thousands of kilometres away from their generating source at considerable speeds. Among several other tsunamis that occurred during the past decade, the 2004 Indian Ocean Tsunami and the 2011 Tohoku Tsunami in Japan, considered to be the deadliest and costliest natural disasters in the history of mankind, respectively, have hit wide stretches of densely populated coastal areas. During these major events, severe destruction of inland structures resulted from the action of extreme hydrodynamic forces induced by tsunami flooding. Subsequent field surveys in which researchers from the University of Ottawa participated ultimately revealed that, in contrast to seismic forces, such hydrodynamic forces are not taken into proper consideration when designing buildings for tsunami prone areas. In view of these limitations, a novel interdisciplinary hydraulic-structural engineering research program was initiated at the University of Ottawa, in cooperation with the Canadian Hydraulic Centre of the National Research Council, to help develop guidelines for the sound design of nearshore structures located in such areas. The present study aims to simulate the physical laboratory experiments performed within the aforementioned research program using a single-phase three-dimensional weakly compressible Smoothed Particle Hydrodynamics (SPH) numerical model. These experiments consist in the violent impact of rapidly advancing tsunami-like hydraulic bores with individual slender structural elements. Such bores are emulated based on the classic dam-break problem. The quantitatively compared measurements include the time-history of the net base horizontal force and of the pressure distribution acting on columns of square and circular cross-sections, as well as flow characteristics such as bore-front velocity and water surface elevation. Good agreement was obtained. Results show that the magnitude and duration of the impulsive force at initial bore impact depend on the degree of entrapped air in the bore-front. The latter was found to increase considerably if the bed of the experimental flume is covered with a thin water layer of even just a few millimetres. In order to avoid large fluctuations in the pressure field and to obtain accurate simulations of the hydrodynamic forces, a Riemann solver-based formulation of the SPH method is utilized. However, this formulation induces excessive numerical diffusion, as sudden and large water surface deformations, such as splashing at initial bore impact, are less accurately reproduced. To investigate this particular issue, the small-scale physical experiment of Kleefsman et al. (2005) is also considered and modeled. Lastly, taking full advantage of the validated numerical model to better understand the underlying flow dynamics, the influence of the experimental test geometry and of the bed condition (i.e. dry vs. wet) is investigated. Numerical results show that when a bore propagates over a wet bed, its front is both deeper and steeper and it also has a lower velocity compared to when it propagates over a dry bed. These differences significantly affect the pressure distributions and resulting hydrodynamic forces acting on impacted structures.

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