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MPEG-4 AVC stream watermarkingHasnaoui, Marwen 28 March 2014 (has links) (PDF)
The present thesis addresses the MPEG-4 AVC stream watermarking and considers two theoretical and applicative challenges, namely ownership protection and content integrity verification.From the theoretical point of view, the thesis main challenge is to develop a unitary watermarking framework (insertion/detection) able to serve the two above mentioned applications in the compressed domain. From the methodological point of view, the challenge is to instantiate this theoretical framework for serving the targeted applications. The thesis first main contribution consists in building the theoretical framework for the multi symbol watermarking based on quantization index modulation (m-QIM). The insertion rule is analytically designed by extending the binary QIM rule. The detection rule is optimized so as to ensure minimal probability of error under additive white Gaussian noise distributed attacks. It is thus demonstrated that the data payload can be increased by a factor of log2m, for prescribed transparency and additive Gaussian noise power. A data payload of 150 bits per minute, i.e. about 20 times larger than the limit imposed by the DCI standard, is obtained. The thesis second main theoretical contribution consists in specifying a preprocessing MPEG-4 AVC shaping operation which can eliminate the intra-frame drift effect. The drift represents the distortion spread in the compressed stream related to the MPEG encoding paradigm. In this respect, the drift distortion propagation problem in MPEG-4 AVC is algebraically expressed and the corresponding equations system is solved under drift-free constraints. The drift-free shaping results in gain in transparency of 2 dB in PSNR
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自願性會計政策變更與盈餘宣告後股價持續反應之研究 / Voluntary Accounting Changes and Post-Earnings Announcement Drift陳怡靜, Chen, Yi Ching Unknown Date (has links)
本研究主要探討當公司管理階層選擇自願性會計政策變更時,是否影響市場對於各該公司所發布相關訊息的反應情形,進而造成股價持續波動之狀況。本研究亦探討是否會計政策的異質性(公司進行會計變更後採用與其同業不同的會計政策)會影響到前述自願性會計變更與股價反映之關係。本研究以採用自願性會計政策變更之美國上市公司為研究對象,樣本期間為1994年至2008年,並將研究對象之競爭對手或產業領導者納入比較樣本。此外,為了觀察股價持續反應的情況,我們設立了季報發布期間和季報發布後期間,以檢驗此研究之假說。
此研究結果顯示,整體來說,自願性會計政策變更在季報發布期間對於未預期盈餘和報酬的關係,會有顯著正向之關聯。此外,考慮了會計政策之異質性後,若公司在會計變更後採取了與同業相同之會計政策,在季報發佈期間對於未預期盈餘和報酬的關係會有顯著正向之關聯,而在季報發佈後期間對於未預期盈餘和報酬的關係會有顯著負向之關聯;若公司在會計變更後採取了與同業不同之會計政策,市場在季報發布後期間對於未預期盈餘和報酬的關係會有顯著正向之關聯,比較多的資訊反映於季報發佈後期間。所以,當公司會計變更後採取異質性的會計政策,外部使用者對於公司發布之相關資訊可能無法及時的消化和理解,進而導致市場遞延反應。
因此,雖然公司採用自願性會計政策變更可能是為了要更真實反映公司之營運狀況,提升外部人士對於公司的實質了解,但根據本研究的實證結果顯示,外部使用者對於自願性會計政策變更後之相關訊息可能需要比較長時間的理解,導致股價會有持續反應的情況。 / This study investigates the relation between voluntary accounting changes (VACs) and post-earnings announcement drift. In addition, this study examines how accounting choice heterogeneity (different from the VAC firms’ peers) before and after VACs is associated with such association. This study collects VAC firms in the U.S. among 1994 to 2008 and identifies the heterogeneity of accounting choices between VAC and non-VAC firms. To test the hypotheses, this study considers the 10-Q filing window and a post-filing drift window.
The results demonstrate that, overall, VACs have a positive effect on the three-day market reactions to 10-Q filings. In addition, after taking into account the accounting choice heterogeneity, this study observes that more of earnings-related stock price reaction occurs in the 10-Q filing window and less of earnings-related market reaction appears in the post-filing drift window. Moreover, VACs are positively associated with the post-filing period drift when VACs are different from their industry peers after VACs. That is, VAC firms adopting different post-change accounting method from non-VAC firms may make external users harder to digest related earnings information and lead to delayed market reaction, thus, more of stock price drift occur in post-filing window.
In conclusion, though VACs may enhance market participants’ understanding of firms’ activities, the results demonstrate that market participants may spend more time to comprehend and digest VAC information disclosed by VAC firms compared to non-VAC firms, which leads to post-earnings announcement drift.
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Next-Generation Perturbed Angular Correlation SpectroscopyNagl, Matthias 13 May 2014 (has links)
No description available.
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Modern Canadian Universities, Mission Drift and Quality of EducationShingadia, Ashwin 11 April 2012 (has links)
This study contributes to theory and public policy in Canada and globally. It uses mixed methodology and triangulation of evidence through policy documents(Bovey,Rae,Drummond),empirical studies and surveys(ranking,NSSE data,regression), CAUT/AUCC and Statistics Canada sources and qualitative sources - writings of university presidents (Bok,Kerr,Fallis),researchers (Rajagopal, Clark et al.)as well,talks with sessionals,teaching assistants and administrators. The framework consists of Altbach's four factors - democratization, the knowledge economy, globalisation and competition and three ideal types for university development - entrepreneurial, liberal education and deliberative. The thesis contrasts classical college with the modern university system. The results show strong evidence for research domination, mission drift and shift towards the entrepreneurial model. Quality is compromised by lowering requirements, compressed courses, less study time, large classes taught by sessionals and TAs, grade inflation and consumerist behaviour, while critical thinking and moral development are neglected.
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Quantifying Seismic Design Criteria For Concrete BuildingsTuken, Ahmet 01 May 2003 (has links) (PDF)
The amount of total and relative sway of a framed or a composite (frame-shear wall) building is of utmost importance in assessing the seismic resistance of the building. Therefore, the design engineer must calculate the sway profile of the building several times during the design process.
However, it is not a simple task to calculate the sway of a three-dimensional structure. Of course, computer programs can do the job, but developing the three-dimensional model becomes necessary, which is obviously tedious and time consuming.
An easy to apply analytical method is developed, which enables the determination of sway profiles of framed and composite buildings subject to seismic loading. Various framed and composite three-dimensional buildings subject to lateral seismic loads are solved by SAP2000 and the proposed analytical method. The sway profiles are compared and found to be in very good agreement. In most cases, the amount of error involved is less than 5 %.
The analytical method is applied to determine sway magnitudes at any desired elevation of the building, the relative sway between two consecutive floors, the slope at any desired point along the height and the curvature distribution of the building from foundation to roof level.
After sway and sway-related properties are known, the requirements of the Turkish Earthquake Code can be evaluated and / or checked.
By using the analytical method, the amount of shear walls necessary to satisfy Turkish Earthquake Code requirements are determined. Thus, a vital design question has been answered, which up till present time, could only be met by rough empirical guidelines.
A mathematical derivation is presented to satisfy the strength requirement of a three-dimensional composite building subject to seismic loading. Thus, the occurrence of shear failure before moment failure in the building is securely avoided.
A design procedure is developed to satisfy the stiffness requirement of composite buildings subject to lateral seismic loading. Some useful tools, such as executable user-friendly programs written by using &ldquo / Borland Delphi&rdquo / , have been developed to make the analysis and design easy for the engineer.
A method is also developed to satisfy the ductility requirement of composite buildings subject to lateral seismic loading based on a plastic analysis. The commonly accepted sway ductility of & / #956 / & / #916 / =5 has been used and successful seismic energy dissipation is thus obtained.
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The Making Of The Visegrad Initiative: Crises And Survivals, Dilemmas And ProspectsKuzum, Sinan 01 December 2004 (has links) (PDF)
This thesis aims to scrutinize the Visegrad Quadruple Initiative as a device of the Central European countries in the process of involving into the re-negotiations in Europe and in world politics. The thesis argues that the Visegrad group was built in order to respond the demands of changing Europe and Euro-Atlantic structures, and thus to overcome the double process of transition and integration. However that was not the only reason to launch the Visegrad regional cooperation. The group produced an affirmative discourse that its members are distinguished from the other countries in transition, so that they are constantly one step forward to &lsquo / return to Europe&rsquo / . In the aftermath of the eastern enlargements of NATO and the EU alike, the original mission of the group, integration with the West, was achieved. That created a profound discussion about the survival of the group. As it is argued in this thesis, the group, as a prosperous and substantial regional cooperation, should rather continue to work in order to have more words to say in the re-negotiations processes. Another argument of the thesis is that the Visegrad group, taking Benelux group as a model in its continuity, is beneficial to produce a common foreign policy tendency among its members as long as the interests of its members are overlapping, otherwise the group is just being a political platform in which its members can share their views in such areas as regional regulations.
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Monitoring gene level biodiversity - aspects and considerations in the context of conservationCharlier, Johan January 2011 (has links)
The objectives of this thesis relate to questions needed to be addressed in the context of genetic monitoring for implementing the Convention on Biological Diversity for the gene level. Genetic monitoring is quantifying temporal changes in population genetic metrics. Specific goals of this thesis include i) synthesizing existing information relevant to genetic monitoring of Swedish species, ii) providing a genetic baseline for the Swedish moose, iii) evaluating the relative performance of nuclear versus organelle genetic markers for detecting population divergence, iv) actually monitoring the genetic composition, structure, level of variation, and effective population size (Ne) and assessing the relation between Ne and the actual number of individuals for an unexploited brown trout population. The concept of conservation genetic monitoring is defined and Swedish priority species for such monitoring are identified; they include highly exploited organisms such as moose, salmonid fishes, Norway spruce, Atlantic cod, and Atlantic herring. Results indicate that the Swedish moose might be more genetically divergent than previously anticipated and appears to be divided into at least three different subpopulations, representing a southern, a central, and a northern population. The relative efficiency of nuclear and organelle markers depends on the relationship between the degree of genetic differentiation at the two types of markers. In turn, this relates to how far the divergence process has progressed. For the monitored brown trout population no indication of systematic change of population structure or allele frequencies was observed over 30 years. Significant genetic drift was found, though, translating into an overall Ne-estimate of ~75. The actual number of adult fish (NC) was assessed as ~600, corresponding to an Ne/NC ratio of 0.13. In spite of the relatively small effective population size monitoring did not reveal loss of genetic variation.
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Novel Analytical Techniques For the Assessment of Degradation of Silicone Elastomers in High Voltage ApplicationsSovar, Robert D. January 2005 (has links)
Over the last 20 years "composite" insulators have been increasingly used in high voltage applications as an alternative traditional materials. More recently, polydimethylsiloxane (PDMS) have been used as weather sheds on these composite insulators. The main attraction with PDMS is that the surface hydrophobicity can be recovered following pollution or surface discharges. Among the possible mechanisms for recovery the most likely is the migration of low molecular weight silicone oil (LMWS) from the bulk to the surface encapsulating pollutant particles. Although it is widely recognised that the migration of LMWS is the cause of this recovery of hydrophobicity, the mechanism of what actually occurs is not well understood. It is also not known for how long this process will continue. The main objective of this study program was to gain improved understanding of the surface hydrophobic recovery process that is unique to polydimethlysiloxane high-voltage insulators. Fundamental knowledge of this mechanism has been increased through the development of the Contact Angle DRIFT Electrostatic Deposition (CADED) novel analytical technique. This technique enabled study of the degradation of silicone elastomers subjected to high voltage environments by closely following LMWS migration from the bulk material to the surface and linking it to the contact angle measurements. The migration rate data showed that the aged material recovered faster that the virgin material. Differences in the rate and maximum surface levels of silicone were seen between materials from different manufacturers. This has significant implications for the life-time of these materials A model system has been developed to examine LMWS diffusion through the bulk material and into the interface of surface and pollutant. This was achieved by examining theoretical and empirically derived equations and using existing experimental data to better understand the mechanism of recovery. This diffusion was Fickian in the initial stages of recovery. X-ray photoelectron spectroscopy (XPS) and contact angle measurements were used to substantiate the degree of degradation in in-field silicone insulators by quantifying the levels of the major degradation products: silica and silica-like material and alumina.
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Exchange processes between littoral and pelagic waters in a stratified lakeMarti, Clelia Luisa January 2004 (has links)
[Truncated abstract] The lake boundaries are an important source of sediment, nutrients and chemicals. For life inside the lake, the exchange between the lake boundaries (littoral) and lake interior (pelagic) is of central importance to Limnology as the net flux of nutrients into the water column is both the driving force and limiting factor for most algae blooms found during the stratification period. Consequently, the understanding of the relevant processes defining such an exchange is a further step toward a sound basis for future decisions by lake managers in order to ensure high water quality. The objective of this research was to investigate the physical processes responsible for the exchange of water and particles between the lake boundaries and the lake interior. An integrated approach using field experiments and 3D modelling as applied to Lake Kinneret (Israel) is presented. The field data revealed large-scale metalimnion oscillations with amplitudes up to 10 m in response to westerly diurnal winds, the existence of a well-defined suspended particle intrusion into the metalimnion of the lake, characterized by high concentrations of organic matter, and a well-mixed benthic boundary layer (BBL). The changes in the thermal structure explained the observed vertical and horizontal movements of the suspended particle intrusion. The horizontal advective transport via the metalimnion, associated with the velocities induced by the basin-scale mode-two Poincare wave, controlled the exchange between the lake boundaries and lake interior on daily time scales. The observed BBL over the lake slope varied markedly with time and space. Detailed comparison of simulation results with field data revealed that the model captured the lake hydrodynamics for time scales from hours to days. The model could then be used to extract the residual motions in the various regions of the lake. The residual motions below the surface layer were predominantly forced by the basin-scale internal wave motions, but the residual motion in the surface layer was found to be very sensitive to the curl of the wind field. The residual circulation was responsible for redistributing mass throughout the lake basin on time scales from days to weeks. A clear connection of dynamics of the BBL with the large-scale features of the flow was addressed. The time history of the mixing in the BBL and the resulting cross-shore flux was shown to vary with the phase of the basin-scale internal waves.
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Simulations for an experiment to probe the in-medium properties of photoproduced vector mesonsClarisse Tur January 2003 (has links)
Thesis (M.S.); Submitted to the Univ. of South Carolina, Columbia, SC (US); 1 Apr 2003. / Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-37" "DOE/ER/40150-2740" Clarisse Tur. 04/01/2003. Report is also available in paper and microfiche from NTIS.
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