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Överreaktion på den svenska aktiemarknaden : En studie om framtida avvikelseavkastningIngels, Henrik, Nilsson, Simon January 2019 (has links)
I denna uppsats undersöks om den svenska aktiemarknaden överreagerar på historisk information över internränta på samma sätt som De Bondt och Thaler (1985) undersöker den amerikanska aktiemarknaden år 1985, vi replikerar även studien för att undersöka om liknande samband uppvisas för effektiv avkastning. Företag på den svenska aktiemarknaden undersöks och rangordnas efter deras internränta samt deras effektiva avkastning. Baserat på detta delas företagen in i två portföljer, portfölj “låg” och portfölj “hög”. Dessa två portföljer jämförs utifrån Buy and Hold Abnormal Return (BHAR) under tre olika tvåårsperioden. Resultaten visar att den svenska aktiemarknaden överreagerar på historisk information beträffande internränta, vilket skapar ett negativt samband mellan historisk internränta och framtida avkastning som en följd av över- och undervärdering av aktier. Dessa resultat är i linje med de presenterade för den amerikanska aktiemarknaden av De Bondt och Thaler och innebär en möjlighet för investerare på den svenska aktiemarknaden till avvikelseavkastning. För historisk effektiv avkastning hittas dock inget liknande samband med framtida avvikelseavkastning.
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Development and Validation of a Modified Clean Agent Draining Model for Total Flooding Fire Suppression SystemsHetrick, Todd M 21 January 2009 (has links)
This project analyzes the validity of theoretical models used to predict the duration (hold time) for which a halon-replacement suppression agent will remain within a protected enclosure. Two current models and one new formulation are investigated; the sharp descending interface model (as applied in NFPA 2001, Annex C), the wide descending interface model (implemented in ISO 14520.1, Annex E), and the thick descending interface model (introduced herein). The thick interface model develops the characteristic thickness as an additional input parameter. Experimental data from 34 full-scale tests designed to characterize the discharge and draining dynamics of seven clean extinguishing agents (CEA) is used to assess model validity. For purposes of model validation the characteristic thickness is regressed from the experimental data although further work may be required to establish the independence of this parameter to other system design and environmental variables. Results show that the wide and sharp interface models' validity is highly sensitive to the threshold of agent concentration decay being modeled; whereas the thick interface prediction method demonstrates increased robustness at any modeled threshold. When the hold time is defined as a 15% decay in agent concentration, experimentally obtained hold time values are roughly 10% shorter than sharp interface predictions, 60% longer than wide interface predictions, and 30% longer than the thick interface model predicts.
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Implementation and Evaluation of a RF Receiver Architecture Using an Undersampling Track-and-Hold Circuit / Implementation och utvärdering av en RF-mottagare baserad på en undersamplande track-and-hold-kretsDahlbäck, Magnus January 2003 (has links)
<p>Today's radio frequency receivers for digital wireless communication are getting more and more complex. A single receiver unit should support multiple bands, have a wide bandwidth, be flexible and show good performance. To fulfil these requirements, new receiver architectures have to be developed and used. One possible alternative is the RF undersampling architecture. </p><p>This thesis evaluates the RF undersampling architecture, which make use of an undersampling track-and-hold circuit with very wide bandwidth to perform direct sampling of the RF carrier before the analogue-to-digital converter. The architecture’s main advantages and drawbacks are identified and analyzed. Also, techniques and improvements to solve or reduce the main problems of the RF undersampling receiver are proposed.</p>
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Constitutive and fatigue crack propagation behaviour of Inconel 718Gustafsson, David January 2010 (has links)
In this licentiate thesis the work done in the TURBO POWER project Influence of high temperature hold times on the fatigue life of nickel-based superalloys will be presented. The overall objective of this project is to develop and evaluate tools for designing against fatigue in gas turbine applications, with special focus on the nickel-based superalloy Inconel 718. Firstly, the constitutive behaviour of the material has been been studied, where focus has been placed on trying to describe the mean stress relaxation and initial softening of the material under intermediate temperatures. Secondly, the fatigue crack propagation behaviour under high temperature hold times has been studied. Focus has here been placed on investigating the main fatigue crack propagation phenomena with the aim of setting up a basis for fatigue crack propagation modelling. This thesis is divided into two parts. The first part describes the general framework, including basic constitutive and fatigue crack propagation behaviour as well as a theoretical background for the constitutive modelling of mean stress relaxation. This framework is then used in the second part, which consists of the four included papers.
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Hematological changes arising from spleen contraction during apnea and altitude in humansRichardson, Matt X. January 2008 (has links)
No description available.
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Design and Implementation of a high-efficiency low-power analog-to-digital converter for high-speed transceiversYounis, Choudhry Jabbar January 2012 (has links)
Modern communication systems require higher data rates which have increased thedemand for high speed transceivers. For a system to work efficiently, all blocks ofthat system should be fast. It can be seen that analog interfaces are the main bottleneckin whole system in terms of speed and power. This fact has led researchersto develop high speed analog to digital converters (ADCs) with low power consumption.Among all the ADCs, flash ADC is the best choice for faster data conversion becauseof its parallel structure. This thesis work describes the design of such a highspeed and low power flash ADC for analog front end (AFE) of a transceiver. Ahigh speed highly linear track and hold (TnH) circuit is needed in front of ADCwhich gives a stable signal at the input of ADC for accurate conversion. Twodifferent track and hold architectures are implemented, one is bootstrap TnH andother is switched source follower TnH. Simulations show that high speed with highlinearity can be achieved from bootstrap TnH circuit which is selected for the ADCdesign.Averaging technique is employed in the preamplifier array of ADC to reduce thestatic offsets of preamplifiers. The averaging technique can be made more efficientby using the smaller number of amplifiers. This can be done by using the interpolationtechnique which reduces the number of amplifiers at the input of ADC. Thereduced number of amplifiers is also advantageous for getting higher bandwidthsince the input capacitance at the first stage of preamplifier array is reduced.The flash ADC is designed and implemented in 150 nm CMOS technology for thesampling rate of 1.6 GSamples/sec. The bootstrap TnH consumes power of 27.95mW from a 1.8 V supply and achieves the signal to noise and distortion ratio(SNDR) of 37.38 dB for an input signal frequency of 195.3 MHz. The ADC withideal TnH and comparator consumes power of 78.2 mW and achieves 4.8 effectivenumber of bits (ENOB).
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Overload effects on the fatigue crack propagation behaviour in Inconel 718Lundström, Erik January 2012 (has links)
In this master thesis, work done in the TURBO POWER project High temperature fatigue crack propagation in nickel-based superalloys during spring 2012 will be presented. The overall objective of this project is to develop and evaluate tools for designing against fatigue in gas turbine applications, with special focus on the crack propagation in the nickel-based superalloy Inconel 718. Experiments have been performed to study the effect of initial overloads, and it has been shown that even for small initial overloads a significant reduction of the crack growth rate is received. Furthermore, FE simulations have been carried out in order to describe the local stress state in front of the crack tip since it is believed to control, at least partly the diffusion of oxygen into the crack tip and thus also the hold time crack growth behaviour of the material. Finally, an evaluation method for the stresses is presented, where the results are averaged over an identifiable process/damaged zone in front of the crack tip.
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Implementation and Evaluation of a RF Receiver Architecture Using an Undersampling Track-and-Hold Circuit / Implementation och utvärdering av en RF-mottagare baserad på en undersamplande track-and-hold-kretsDahlbäck, Magnus January 2003 (has links)
Today's radio frequency receivers for digital wireless communication are getting more and more complex. A single receiver unit should support multiple bands, have a wide bandwidth, be flexible and show good performance. To fulfil these requirements, new receiver architectures have to be developed and used. One possible alternative is the RF undersampling architecture. This thesis evaluates the RF undersampling architecture, which make use of an undersampling track-and-hold circuit with very wide bandwidth to perform direct sampling of the RF carrier before the analogue-to-digital converter. The architecture’s main advantages and drawbacks are identified and analyzed. Also, techniques and improvements to solve or reduce the main problems of the RF undersampling receiver are proposed.
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The Analysis of Operation Efficiency between Banks inside and outside of Financial Holding CompaniesChou, Yu-ming 23 January 2007 (has links)
Abstract
After our country joins WTO, will face the strong capital competition pressure of the international large-scale financial institution, and after foreign businessman's bank has grand capital, the industry manages completely dark, in the face of so strong impact country the financial market fluctuates and aggravates, has increased the operation pressure of the domestic banking, too. How to transform this pressure into helping hand, utilize aquistion and merger to consider complementarily , lower costs then improve the competitiveness, it is really the question which the banking of Taiwan needs to face at present.
Domestic aquistion and merger case or makes up the financial domain that the financial holding company has already affected 14 financial holding companies in Taiwan to reform with the operation pattern jointly at present, but these financial holding companies can reach the value expected and comprehensive result which is greater than two of one plus one ( Synergy ) The goal needs checking and tests directly.
It does not belong to the financial holding company at home to spy on put the independent bank, in case of financial market saturation, the profit shrinks, the income reduces by a wide margin, the quality of the assets is not good, so that is it put rate is it wait for numerous unfavourable factor to remain high to exceed, how face assets huge financial holding company lay big bank create life their extremely, whether it is influenced that purpose calls it and manages the performance; Establish financial holding company purpose is it can reach category economy and purpose of the large-scale production to call separately. Purpose of this research, focus on wanting to untie it under the trend of the international finance, can really improve the bank and manage the performance and business efficiency of independent bank to establish the financial holding company under the double pressure of the domestic trouble and foreign invasion and really not so good as finance holding company bank put.
Because of above-mentioned backgrounds and motives, so this text hope book probe into by document, materials collect and utilize materials not to make analytic approach of holding in place with a net ( Data Envelopment Analysis , abbreviated as DEA) ,displaying the result of study, it is by offering competent authorities or the financial holding company policymaker to the government and wanting to set up some reference suggestions of bank of the financial holding company.
Keywords: Data Envelopment Analysis , The materials charter and hold analytic approach, technological efficiency, pure technological efficiency, scale efficiency
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A 12-Bits/10.24MHz Sample Rate Switched-Current Sigma-Delta Modulator with OP-Amp Active IntegratorChao, Chun-Cheng 31 July 2008 (has links)
In this thesis, a switched-current sigma-delta modulator (SDM) with op-amp active integrator is proposed. The major study is focused on using the op-amp to reduce the input impedance for high speed and high solution and utilizes the dummy switch to decrease the clock feedthrough (CFT) error. We use a sample-and-hold circuit which consists of an op-amp active memory cell and a dummy switch circuit to implement the integrator. It is applied to the building blocks of SDM.
The modulator is a second order sigma-delta modulator. A current comparator transforms the current signal into digital voltage signal. A single-bit digital-to-analog (D/A) feedback circuit is used to convert the one-bit digital output to the SI integrator .The modulator is designed in the current mode technique.
The delta-sigma modulator simulates using the parameters of the TSMC 0.35£gm CMOS process. The simulation results show that the signal to noise plus distortion ratio (SNDR) is 72 dB, the sampling rate is 10.24MHz, the oversampling ratio is 128, the power consumption is 21mW, the dynamic range is about 70dB, and the power supply is 3.3V.
Furthermore, the circuit is verified by cadence-hspice simulation.
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