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The 3-D fluorescence microscope has become the method of choice in biological sciences for living cells study. However, the data acquired with conventional3-D fluorescence microscopy are not quantitatively significant because of distortions induced by the optical acquisition process. Reliable measurements need the correction of theses distortions. Knowing the instrument impulse response, also known as the PSF, one can consider the backward process of convolution induced by the microscope, known as "deconvolution". However, when the system response is not invariant in the observation field, the classical algorithms can introduce large errors in the results. In this thesis we propose a new approach, which can be easily adapted to any classical deconvolution algorithm, direct or iterative, for bypassing the non-invariance PSF problem, without any modification to the later. Based on the hypothesis that the minimal error in a restored image using non-invariance assumption is located near the used PSF position, the EMMA (Evolutive Merging Masks Algorithm) blends multiple deconvolutions in the invariance assumption using a specific merging mask set. In order to obtain sufficient number of measured PSF at various depths for a better restoration using EMMA (or any other depth-variant deconvolution algorithm) we propose a 3D PSF interpolation algorithm based on the image moments theory using Zernike polynomials as decomposition base. The known PSF are decomposed into Zernike moments set and each moment's variation is fitted into a polynomial function, the resulting functions are then used to interpolate the needed PSF's Zernike moments set to reconstruct the interpolated PSF.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / A MIMO radar system for target localization is presented which uses direct-sequence CDMA (DS-CDMA) waveforms. The received DS-CDMA signal at each antenna is expressed directly in terms of the target positions. The waveforms employed are Gold sequences, and hence are not exactly orthogonal. A generalized successive interference cancellation (GSIC) approach is used to resolve multiple scatterers and reduce clutter. Simulation results are presented which suggest the capability to detect weak scatterers in the presence of clutter using the cancellation method.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper introduced a fast scanning and waiting acquisition method for a DS/FH receiver used in the telemetry field. Mathematic model of the hybrid DS/FH system’s acquisition process is given and discussed. The average acquisition time expression using this method and generalized average acquisition time formula is derived also. The validity of the proposed algorithm is verified after simulation. In the circumstances of Additive Gauss White Noise for the channel, simulation result at Ec/N0= -15dB shows that the average acquisition time is decreased almost 4 times than that of waiting and searching method.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper proposes a problem that the error tolerance property of spread spectrum sequence influences the performance of spread spectrum system. Then the relation is analyzed between the error tolerance property and the correlation property of binary sequence when correlation detection is proceeded, and the theoretical limitation of error tolerance is given. Finally, we investigate the relationship between the determination of the output decision threshold of correlation, the probability of correlation peak detection and the error tolerance of the spread spectrum sequence.

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Based on the fact that two topological conjugacy chaotic maps have identical dynamical behaviors, this paper proposes a method generating spreadspectrum sequences by creating chaotic maps topological conjugacy to Kent- Map, and analyses the correlation properties of the chaotic spread-spectrum sequences. The results of simulation verified the correctness of the theoretical analysis.

This thesis,firstly, studies the impact of financial liberalization and political instability on economic growth and quantitatively examines the relative importance of the identified underling reasons of Argentine riddle by using an innovative econometric methodology and unique data set: it presents power ARCH estimates for Argentina from 1896 to 2000. The main results show that the long-run effect of financial liberalization on economic growth is positive while the short-run effect is negative, albeit substantially smaller. The political instability effects are substantially larger in the short-run than in the long-run. We also investigate potential mechanisms for the effects of financial liberalization and political instability on economic growth: direct impact or happening through the variation of growth volatility. Our results also suggest that financial development, trade openness and political instability are the main factors to explain the Argentine decline. Furthermore, real business cycle variability - growth relationship and the link between inflation and its uncertainty are investigated by using monthly data of four Asian countries/regions (Japan, South Korea, Singapore and Taiwan) and parametric power ARCH methodology to proxy uncertainty. We fnd that more uncertainty about output leads to a higher rate of growth in three of the four countries/regions and the form of the uncertainty matters. Output growth reduces its uncertainty in all countries/regions via inflation uncertainty except Singapore. For all countries/regions, inflation significantly raises inflation uncertainty as predicted by Friedman. On the other hand, increased uncertainty affects inflation positively in Japan and Singapore, which support the Cukierman-Meltzer hypothesis. We find a negative sign for Taiwan which is in accordance with the Holland hypothesis when error term was normally distributed, however, this result is not statistically significant when the student-t distribution is applied. Interestingly, South Korea’s data reveals a positive sign initially, however, it turns around when a structural dummy is incorporated. This dramatic outcome in favour of the Holland hypothesis, and chimes in with Dueker and Kim (1999), who claim that the inflation was strictly controlled by the South Korean monetary authority. In addition, this thesis investigates two-way causal relationships between spread, volatility and volume in the FTSE100 stock index over the period from 1992 to 2004 by using bivariate AR-FI-GARCH model and multiple measurements of risk and spread. The measurements of the spread include relative bid-ask spread, effective bid-ask spread, the inventory cost component of the bid-ask spread and the information cost component of the bid-ask spread. Risk is proxied by two measurements of price volatility: the close-to-close volatility and the range-based volatility. We also take the impact of electronic trading into account. Our results suggest that the spread and volume are positively impacted by volatility simultaneously. In addition, both volatility and volume are negatively affected by the spread. Furthermore, we find that the inventory cost component of the spread has a negative effect on volatility, in contrast, the information component of the spread positively impacts volatility. These results support the argument that speculation generates volatility in the market and higher transaction costs bene t stability of the market.

The cross-spread formed by intersecting source and receiver lines, or “hybrid gather” consisting of all common mid-points (CMPs) in a reflection patch defined by the acquisition geometry, has been revived in recent years as a possible solution to the increasing need for ever-improving imaging of 3-D seismic reflection data. These hybrid gathers, however, are currently not widely used in processing. Development of processing procedures for hybrid gathers is needed to further the efficiency of their application. The use of hybrid gathers in processing is justified by their performance as an areal array in attenuating both random and coherent noise from all azimuthal directions. Hybrid gathers also allow for azimuthal filtering to correct for wave propagation effects. Through an azimuthal analysis in an azimuthally anisotropic medium, the effects of structural dip on reflection time can be isolated and separated from pre-stack propagation effects of the media, particularly distortions due to azimuthal anisotropy. A binning strategy is determined for hybrid gathers which best allows for azimuthal anisotropy to be observed and distinguished from structural dip. This allows for improved velocity estimation for imaging and separate analysis of azimuthal variations in propagation properties of subsurface media at an early stage in the processing sequence. The degree and orientation of the anisotropy can then be estimated using a semblance method. / text

In recent years, issues about credit risk attract more and more attentions. This thesis provides some empirical evidence for the behavior of credit spreads in Taiwan based on a Markov model proposed by Jarrow, Lando, and Turnbull (1997). Although the estimated risk premium adjustments increases as the credit rating level goes downward, it does not exist robust relations between credit yield spreads and credit ratings. Apparently, the model does not fit the real condition well because of some structural factors and limitations. I try to suggest some possible explanations for this phenomenon. Despites some poor performances of this model, these results still offer some directions to reconsider the valuation of straight corporate bonds in Taiwan.

Práce podrobně charakterizuje a analyzuje strukturální modely kreditního rizika. Nejprve je vymezena základní myšlenka strukturálních modelů, která je spojena s pracemi Blacka, Scholese (1973) a Mertona (1974). Následuje rozšíření v podobě first-passage-time modelů jak s konstantní, tak se stochastickou úrokovou sazbou. Dále je zmíněn i Zhou (1997) model a empirická verifikace a využití strukturálních modelů. Na závěr jsou některé strukturální modely aplikovány na společnosti Telecom a ČEZ.