Cette thèse présente une étude pour l'interprétation automatique d'images en milieu urbain. Nous proposons une application permettant de reconnaître différents monuments au sein d'images représentant des scènes complexes. La problématique principale est ici de différencier l'information locale extraite des points d'intérêt du bâtiment recherché parmi tous les points extraits de l'image. En effet, la particularité d'une image en milieu urbain vient de la nature publique de la scène. L'objet que l'on cherche à identifier est au milieu de divers autres objets pouvant interférer avec ce dernier. Nous présentons dans une première partie un état de l'art des méthodes de reconnaissance d’images en se concentrant sur l'utilisation de points d'intérêts locaux ainsi que des bases de données pouvant être employées lors des phases d'expérimentation. Nous retenons au final le modèle de sac de mots (BOW) appliqué aux descripteurs locaux SIFT (Scale-Invariant Feature Transform). Dans un second temps nous proposons une approche de classification des données locales faisant intervenir le modèle de machine à vecteurs de support (SVM). L'intérêt présenté dans cette approche proposée est le faible nombre de données requises lors de la phase d'entraînement des modèles. Différentes stratégies d'entraînement et de classification sont exposées ici. Une troisième partie suggère l'ajout d'une correction géométrique de la classification obtenue précédemment. Nous obtenons ainsi une classification non seulement de l'information locale mais aussi visuelle permettant ainsi une cohérence géométrique de la distribution des points d'intérêt. Enfin, un dernier chapitre présente les résultats expérimentaux obtenus, notamment sur des bâtiments de Paris et d'Oxford / This thesis presents a study for an automatic interpretation of urban images. We propose an application for the retrieval of different landmarks in images representing complex scenes. The main issue here is to differentiate the local information extracted from the key-points of the desired building from all the points extracted within the entire image. Indeed, an urban area image is specific by the public nature of the scene depicted. The object sought to be identified is fused within various other objects that can interfere. First of all, we present a state of the art about image recognition and retrieval methods focusing on local points of interest. Databases that can be used during the phases of experimentation are also exposed in a second chapter. We finally retain the Bag of Words modèle applied to local SIFT descriptors. In a second part, we propose a local data classification approach involving the Support Vector Machine model. The interest shown with this proposed approach is the low number of data required during the training phase of the models. Different training and classification strategies are also discussed. A third step suggests the addition of a geometric correction on the classification obtained previously. We thus obtain a classification not only for the local information but also for the visual information allowing thereby a geometric consistency of the points of interest. Finally, a last chapter presents the experimental results obtained, in particular involving images of buildings in Paris and Oxford

近年來，在中國大陸市場有大量公司進行掛牌上市的同時，也有越來越多的公司出現債務逾期甚至是違約的情況。考慮到目前中國經濟增速放緩，處在轉型發展的複雜階段，銀行信貸等資金供應鏈需要謹慎評估企業出現財務困境的風險。但是我們發現金融機構在平常管理信貸業務的時候會盲目地看重高額利潤的回報而忽略借款者潛在的財務危機，而且投資人在進行投資分析的時候往往也會忽略企業的財務狀況而使自己遭受損失，因此從企業的財務狀況入手對其進行財務困境機率的評估有非常重大的現實意義。 本文通過對企業財務指標進行相關分析以構建公司財務困境機率評估模型。本文選取了不良貸款率最高的製造業作為研究對象，將2015年滬深兩地的124家上市製造業公司的財務資料作為訓練樣本，將2014年120家上市公司的財務資料作為檢驗樣本，將交易所特別處理公司劃分為非正常組公司，其餘為正常組。本文通過篩選得出23個財務指標作為研究變數，引入了 Logistic 模型與 SVM 模型，針對單一模型的預測結果在準確率和穩定性方面不理想的問題引入了基於 Logistic 模型、SVM 模型的組合模型，並用檢驗樣本進行了四個模型的相關實證分析，比較了四個模型之間的準確度。 對四個模型進行實證分析的結果表明：Logistic模型穩健性好、可解釋性強、建模過程簡單易操作，但分類精度略低於 SVM 模型；SVM雖然分類精度高，但缺乏可解釋性和穩定性，且建模過程依賴專家知識和經驗；Logistic -SVM 組合模型則兼具其優點，預測精確度較單一模型均有提高，而且研究發現異態並行結構優於串型結構。通過本文建立的模型可以計算出企業的陷入財務困境的機率，有效評估企業的違約風險，進而為相關金融機構和投資者提供放款或投資的判斷依據。 / At present, more and more companies are listed in the Chinese mainland market. At the same time, more and more companies are frequently at risk of default and overdue. Given the slowdown in China's economic growth and the complex environment of transformation and development, the supply of funds such as bank loans and other capital needs to be cautious, debt default, loan overdue cases are still likely to occur one after another. However, we find that financial institutions blindly value the return of high profits while ignoring the potential financial crisis of borrowers in the normal management of credit business, it is of great significance to start with the financial status of a company to assess the probability of financial distress. This paper builds a company default probability assessment model by analyzing the financial indicators of enterprises. This paper selects the manufacturing industry with the highest NPL as the research object. Taking the financial data of 124 listed manufacturing companies in Shanghai and Shenzhen in 2015 as the training samples, using the financial data of 120 listed companies in 2014 as the test sample, Exchange special treatment companies divided into non-normal group companies, the rest for the normal group. According to the data of its 2015 financial indicators, 23 financial indicators were screened out as research variables, and a comprehensive analysis was carried out. The Logistic model and SVM model were introduced. Combined model was introduced based on the Logistic model and SVM model to solve the problem that the prediction accuracy and stability of the single model were not ideal,. Finally, empirical analysis of the four models is carried out using the sample data of listed companies in 2014, and the accuracy of the four models is compared. The results of empirical analysis of the four models show that Logistic regression model has no strict assumptions on the data, a better stability and interpretation, but the classification accuracy is slightly lower than the SVM model. The SVM model has higher classification accuracy, but the disadvantage is the lack of interpretability and stability, the modeling process depends on expert knowledge and experience. In order to balance the stability of Logistic model and the accuracy of SVM model, this paper introduces a combined model based on Logistic model and SVM model. The analysis shows that the prediction accuracy of combined model is higher than that of single model, the combination of Logistic regression model and SVM model based on Parallel structure has a higher prediction accuracy than Sequential structure. The model established in this paper can calculate the default probability of an enterprise, effectively assess companies’ risk of financial distress, and then provide the judgment basis for the relevant financial institutions and investors to lend or invest.