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Ce travail présente l’algorithme GARRLiC (Generalized Aerosol Retrieval from Radiometer and Lidar Combined data). Le but de cet algorithme est d’inverser simultanément les mesures co-localisées d’un LiDAR et d’un photomètre solaire. Cet algorithme original permet de déduire un ensemble très complet de paramètres descriptifs de l’aérosol atmosphérique, paramètres à la fois intégrés sur la colonne atmosphérique et résolus verticalement. GARRLiC est basée sur la recherche du meilleur ajustement de données multi-sources avec contraintes a priori. Il est basée sur la recherche de la meilleure solution selon un ensemble de critères statistiques. Les paramètres déduits sont de 2 types. Certains sont des quantités intégrées sur la colonne atmosphériques tandis que d’autres sont fonction de l’altitude comme la concentration en particules pour les deux modes dimensionnels fin et grossier. Une étude de sensibilité a montré que l’ensemble des paramètres peut être restitué avec une bonne précision dans toutes les situations considérées. L’étude indique une précision moins bonne pour le mode fin et qu’en général la précision est moindre à faible épaisseur optique. Elle a également montré que la précision sur l’indice de réfraction pouvait être accrue si l’on prenait en compte la mesure de polarisation issue du photomètre solaire. L’impact de la prise en compte de mesure LiDAR et de bruit sur les mesures a été étudié. GARRLiC a été appliqué à des mesures réelles obtenues à Minsk (Biélorussie) et Lille (France). L’approche employée ici peut être facilement modifiée pour retrouver les propriétés de l’aérosol à partir de multiples combinaisons d’instruments de télédétection passif et actif. / This thesis presents the GARRLiC algorithm (Generalized Aerosol Retrieval from Ra- diometer and Lidar Combined data) that simultaneously inverts co-incident lidar and sun-photometer observations and derives a united set of aerosol parameters that describe both columnar and vertical aerosol properties. GARRLiC searches for the best fit of the multi-source measurements together with a priori constraints on aerosol characteristics through the continuous space of all possi- ble solutions under statistically formulated criteria. It retrieves height independent size distribution, complex refractive index and fraction of spherical particles together with vertically resolved aerosol concentration, all differentiated between fine and coarse aerosol modes. The potential and limitations of the method are demonstrated by sensitivity tests. The tests showed that the complete set of aerosol parameters for each aerosol component can be robustly derived with acceptable accuracy in all considered situations. Limited sen- sitivity to the properties of the fine mode and dependence of retrieval accuracy on the aerosol optical thickness for both modes were found. It was shown that sensitivity to fine mode refractive index could be improved by accounting for polarization data provided by passive instruments. The effects of the presence of lidar data and random noise on aerosol retrievals were studied. The algorithm was also applied to the real lidar and radiometer observations obtained over Minsk (Belarus) and Lille (France) AERONET sites. Suggested approach could be easily modified to retrieve aerosol properties from all possible combinations of existing passive and active remote sensing instruments.

在多組壽命試驗中，為了準確地估計模型的參數，我們必須找出最合適的實驗品數量，以分配給每一個應力水平。近來, Ng, Chan and Balakrishnan(2006)，在完整樣本情況下，利用「極值回歸模型」發展了找尋實驗品數量最合適的分配方法。其後，Ka, Chan, Ng and Balakrishnan (2011)在同一個回歸模型下，研究了對於「II型截尾樣本」最合適的分配方法。因為我們仍未確立對「I型截尾樣本」的最合適分配方法，所以我們將會在本篇論文中探討如何在「I型截尾壽命試驗」中找出最合適的實驗品分配方法。 / 在本論文中，我們會利用最大似然估計的方法去估計模型參數。我們也會計算出「逆費雪訊息矩陣」(「漸近方差協方差矩陣」)I⁻¹，用以量度參數估計值的準確度。以下是三個對最合適分配方法的決定準則: / 1.費雪訊息矩陣的行列式最大化, / 2. ν1估計值的方差最小化, var( ν1)(V -優化準則 ) / 3.漸近方差協方差矩陣的跡最小化, tr(⁻¹)(A-優化準則 ) / 我們也會討論在「極值回歸模型」的特例：「指數回歸模型」之下最合適的分配方法。 / In multi-group life-testing experiment, it is essential to optimize the allocation of the items under test to dierent stress levels in order to estimate the model parameter accurately. Recently Ng, Chan and Balakrishnan(2006) developed the optimal allocation for complete sample case with extreme value regression model, and Ka, Chan, Ng and Balakrishnan (2011) discussed about the optimal allocation for Type -II censoring cases with the same model. The optimal allocation for Type-I censoring scheme has not been established, so in this thesis, we are going to investigate the optimal allocation if Type-I censoring scheme is adopted in life-testing experiment. / Maximum likelihood estimation method will be adopted in this thesis for estimating model parameter. The inverted Fisher information matrix (asymptotic variance -covariance matrix),I⁻¹ , will be derived and used to measure the accuracy of the estimated parameters. The optimal allocation will be determined based on three optimal criteria: / 1. Maximizing the determinant of the expected Fisher Information matrix, / 2. Minimizing the variance of the estimator of ν1, var( ν1) (V -optimality ) / 3. Minimizing the trace of the variance-covariance matrix, tr(I⁻¹) (A-optimality ) / Optimal allocation under the exponential regression model,which is a spe¬cial case of extreme value regression model, will also be discussed. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / So, Hon Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 46-48). / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgement --- p.i / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Accelerated Life Test --- p.1 / Chapter 1.2 --- Life-Stress Relationship --- p.1 / Chapter 1.3 --- Type I Censoring --- p.3 / Chapter 1.4 --- Optimal Allocation --- p.3 / Chapter 1.5 --- The Scope of the Thesis --- p.4 / Chapter 2 --- Extreme Value Regression Model --- p.5 / Chapter 2.1 --- Introduction --- p.5 / Chapter 2.2 --- Model and Maximum Likelihood Estimation --- p.5 / Chapter 2.3 --- Expected Fisher Information --- p.8 / Chapter 3 --- Criteria for Optimization and the Optimal Allocation --- p.12 / Chapter 3.1 --- Introduction --- p.12 / Chapter 3.2 --- Criteria for Optimization --- p.12 / Chapter 3.3 --- Numerical Illustrations and the Optimal Allocation --- p.14 / Chapter 4 --- Sensitivity Analysis --- p.17 / Chapter 4.1 --- Introduction --- p.17 / Chapter 4.2 --- Sensitivity Analysis --- p.17 / Chapter 4.3 --- Numerical Illustrations --- p.19 / Chapter 4.3.1 --- Illustration with McCool (1980) Data --- p.19 / Chapter 4.3.2 --- Further Study --- p.21 / Chapter 5 --- Exponential Regression Estimation --- p.26 / Chapter 5.1 --- Introduction --- p.26 / Chapter 5.2 --- The Model and the Likelihood Inference --- p.27 / Chapter 5.3 --- Optimal Sample Size Allocation for Estimation of Model Pa- rameters --- p.30 / Chapter 5.4 --- Numerical Illustration --- p.33 / Chapter 5.5 --- Sensitivity Analysis --- p.35 / Chapter 5.5.1 --- Parameter Misspeci cation --- p.35 / Chapter 5.5.2 --- Censoring Time --- p.38 / Chapter 5.5.3 --- Further Study --- p.40 / Chapter 6 --- Conclusion and Further Research --- p.44

Includes copies of articles co-authored by the author during the preparation of this thesis. Includes bibliographical references (leaves 233-245). A three-field photometer was employed at the University of Adelaide's Buckland Park field site to collect optical observations of the 557.7nm OI and 730nm OH airglow emissions on an almost continuous basis since May 1995 to May 2000, with observations made whenever the moon was not up.

Includes copies of articles co-authored by the author during the preparation of this thesis. Includes bibliographical references. Electronic publication; full text available in PDF format; abstract in HTML format. A three-field photometer was employed at the University of Adelaide's Buckland Park field site to collect optical observations of the 557.7nm OI and 730nm OH airglow emissions on an almost continuous basis since May 1995 to May 2000, with observations made whenever the moon was not up. Electronic reproduction.[Australia] :Australian Digital Theses Program,2001.

Thesis (M.Sc.)--York University, 2004. Graduate Programme in Computer Science. / Typescript. Includes bibliographical references (leaves 104-109). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL:http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss&rft%5Fval%5Ffmt=info:ofi/fmt:kev:mtx:dissertation&rft%5Fdat=xri:pqdiss:MQ99411

Reproduction de : Thèse de doctorat : Vision et Robotique : Clermont-Ferrand 2 : 2005. / Thèse avec annexes. Titre provenant de l'écran-titre. Bibliogr. p. 231-242.

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