A Method for SINS Alignment with Large Initial Misalignment Angles Based on Kalman Filter with Parameters Resetting

In the initial alignment process of strapdown inertial navigation system (SINS), large initial misalignment angles always bring nonlinear problem, which causes alignment failure when the classical linear error model and standard Kalman filter are used. In this paper, the problem of large misalignment angles in SINS initial alignment is investigated, and the key reason for alignment failure is given as the state covariance from Kalman filter cannot represent the true one during the steady filtering process. According to the analysis, an alignment method for SINS based on multiresetting the state covariance matrix of Kalman filter is designed to deal with large initial misalignment angles, in which classical linear error model and standard Kalman filter are used, but the state covariance matrix should be multireset before the steady process until large misalignment angles are decreased to small ones. The performance of the proposed method is evaluated by simulation and car test, and the results indicate that the proposed method can fulfill initial alignment with large misalignment angles effectively and the alignment accuracy of the proposed method is as precise as that of alignment with small misalignment angles

A new approach to the study on counterexamples of generic sentences: From the perspective of interactive reference point-target relationship and re-categorization model

Based on deficiencies of existing researches, this paper, aiming at taking the tolerance of counterexamples reflecting seeming syntax-semantic mismatch in generic sentences, and the online cognitive process of these sentences into the same analyzing framework, proposes the Interactive Reference Point-target Relationship and Re-categorization Model (IRPR-RC Model) to give a unified explanation to the main types of counterexample-tolerating generic sentences (GS), thus further fulfilling the generalization commitment of cognitive linguistics. According to this model: 1) there is an interaction relationship between reference points and targets connecting generic words and attribute words in counterexample-tolerating generic sentences (GS); 2) this interactive relationship provides the premise for re-categorization, which selects a particular sub-category and makes it salient. This process can also be viewed as a phenomenon of attribute words coercing the generic words; 3) the model can be divided into three types: Focusing Type, Imbedding Type and Repulsing Type, according to different operation mechanism of IRPR-RC Model in counterexample-tolerating generic sentences (GS)

When the authoritarian China meets Internet : A critical analysis of Chinese newspaper discourse on online phenomenon “Internet anti anti-corruption”

This thesis reviews the origin and development of 'Internet anti-corruption', a new Chinese online phenomenon. I examine newspaper discourse covering this phenomenon, aiming to show it is discursively constructed in the press based on three typical cases occurring in 2012. The construction of legitimacy on this new phenomenon is the focus of the study. Drawing from the sociological and political perspective of power, this study uses discourse analysis theory combined with media discourse theory, focusing on media discourse, and targets to uncover the power positions and structures in the discourse. Empirically, the study is based on 125 articles. Methodologically, the study utilizes a critical approach of critical discourse analysis to explore the legitimacy strategies and structures of this Internet phenomenon within the Chinese social and political context. The legitimacy is examined with the help of Fairclough’s discourse analysis and van Leeuwen’s framework of legitimation in discourse. This thesis argues that the construction of legitimacy sustained the power relations in China and maintained the state dominance. Nevertheless, it is worth noticing that the social power is recognized in society by being identified as new form of public supervision. Related to the social and political context, online social power in the contemporary China is gaining recognition and acceptance by party state and society in general. However, the dominance of state power on the Internet actions is mainly maintained and reproduced from media discourse. The construction of legitimacy for Internet anti-corruption, in one way, endows relative legitimacy to the Internet users; in another way, it propagates the new presidency and reaffirms the state power. In the end, the legitimation of 'Internet anti-corruption' in media is more likely an effort to legitimize the party-state power over the Internet which reflects its authoritarian nature. The main findings of the thesis concern the construction of public discourse on Chinese online incidents and contribute to the further understanding of public sphere and civil society development

Risk Management Efficiency in UK Non-Life Insurance Companies

Insurers are being exposed to huge adverse risk in current financial market, consequently, risk management turn out to be a competitive tool for them. The present study was designed to investigate current situation of risk management efficiency in UK non-life insurers, where the top five non-life insurers in UK: Aviva, RSA, Bupa, Direct Line and Allianz were selected as samples for both qualitative and quantitative analysis. Annual reports of the five sample companies were the only data source for the study. In qualitative part, risk exposures, risk management technics and strategies of the five sample companies were analysed through five aspects: operational risk, market risk, credit risk, liquidity risk and reputational risks. In quantitative part, DEA method and DEAP (version 2.1) software were applied to assess integrated risk management efficiency of the five sample companies. The results of qualitative part demonstrated that the five major risk exposures of the five non-life insurance companies in UK were under control during 2017, while, the risk control methods applied in the five insurers during 2017 were various. What’s more, without any exercisable plan for monitoring or controlling, reputational risk was considered as a minor risk by most of the insurers. As for the results obtained in quantitative section, risk management efficiency was increased in 2016, which seems to the result of great effort non-life insurance companies had made in 2016. While, risk management efficiency declined for all the five firms in 2017 because they contribute great amount of capital to intangible assets, which appears to be risky for insurers. Finally, the suggestions for non-life insurance companies were provided and exercisable plan for improving reputational risk was given, for example, risk quantifying measurement and SCR (solvency capital requirement) strategy applied by RSA (Royal & Sun Alliance) tend to be useful methods to increase efficiency of risk management. For further study, more sample companies should be analysed based on multiple data sources to gain more reliable results. Besides, it is suggested to have deeper studies about how the application of quantitative measurement approach in risk management affect the efficiency of risk management in non-life insurance companies

H∞ filter for flexure deformation and lever arm effect compensation in M/S INS integration

ABSTRACTOn ship, especially on large ship, the flexure deformation between Master (M)/Slave (S) Inertial Navigation System (INS) is a key factor which determines the accuracy of the integrated system of M/S INS. In engineering this flexure deformation will be increased with the added ship size. In the M/S INS integrated system, the attitude error between MINS and SINS cannot really reflect the misalignment angle change of SINS due to the flexure deformation. At the same time, the flexure deformation will bring the change of the lever arm size, which further induces the uncertainty of lever arm velocity, resulting in the velocity matching error. To solve this problem, a H∞ algorithm is proposed, in which the attitude and velocity matching error caused by deformation is considered as measurement noise with limited energy, and measurement noise will be restrained by the robustness of H∞ filter. Based on the classical “attitude plus velocity” matching method, the progress of M/S INS information fusion is simulated and compared by using three kinds of schemes, which are known and unknown flexure deformation with standard Kalman filter, and unknown flexure deformation with H∞ filter, respectively. Simulation results indicate that H∞ filter can effectively improve the accuracy of information fusion when flexure deformation is unknown but non-ignorable