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1.
正During the first decade of the 21st century, global support for major international frameworks, such as the Sendai Framework for Disaster Risk Reduction and the Paris Agreement on Climate Change, and the Sustainable Development Goals (SDGs), represented international consensus on reducing mortal and economic risks and vulnerabilities of human populations around the world. These risks were recognized to be a consequence of modern development,  相似文献   

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This paper investigates the construction of a fuzzy functional observer for nonlinear systems with time-delays, and the application of the observer to estimate the state functions of the parallel distributed compensation controller for stabilizing the system. Two types of time-delays are considered: constant and time-varying delays with bounded time derivative. Stability conditions are obtained using Lyapunov–Krasovskii functional approach; and the conditions are transformed into linear matrix inequalities with equality constraints so that observer parameters can be calculated using the solution of these inequalities. Functional observer construction procedures are presented considering both constant and time-varying time-delays. Two examples, including one for obtaining a power system stabilizer for a single machine infinite bus system, are presented to illustrate effectiveness of the proposed design procedures.  相似文献   

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In comparison with the people having the normal color vision, the people with color vision impairment such as dichromats have the difficulty to distinguish the colors in certain combinations. This may pose an impediment of the visual communication in the recent wide spreading of the use of colors. In order to address this problem, in this paper, we propose a novel lightness modification method to improve the visibility of the color image for the color vision impaired. In the proposed method, the lightness modification is only carried out around contours of objects to realize the Craik–O'Brien effect, which is an perceptual illusion of the contrast, for dichromats. Furthermore, in the proposed method, it is tried to preserve the impression given by original color image by lessening the change of the color as possible while providing the perceptible and comprehensible color image for dichromats. Through some examples, the effectiveness and the validity of the proposed method are verified.  相似文献   

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This paper proposes a new watermarking approach using dynamic stochastic resonance (DSR) based tuning operation to extract the watermark logo from the watermarked image that has undergone different intentional and signal processing attacks. This method is intended to provide remedies from the shortcomings of the technique proposed by Lin et al. (2008), and invalidates the effect of intentional attacks recently designed by Meerwald et al. (2009). The algorithm incorporates three level image decomposition using lifting wavelet transform (LWT) and low-pass subband is utilized for data hiding purpose. Watermark bits are embedded into the blocks of non-overlapped wavelet coefficients of the cover image by quantizing the two maximum coefficients of the corresponding block. In watermark extraction process, the DSR is applied by performing the tuning operation on coefficient blocks of attacked watermarked image. It is a parameter dependent approach that enhances the performance of watermark extraction, where the parameters of DSR inherently depend on the image properties such as standard deviation or variance. As far as security is concerned, the randomization of wavelet coefficients, blocks, and watermark bits helps the framework to be more secure. The proposed technique is also examined against multiple watermarking attack and successfully proves its authenticity and ownership. Comparison of the proposed technique with recent techniques shows remarkable improvement in terms of robustness and security against various intentional, signal processing, and geometrical attacks.  相似文献   

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This study investigates empirically whether patents can be signals to financial markets, thus reducing problems of asymmetric information. In particular we study how patenting behaviour impacts on the way investors perceive software firms’ growth potential through an increase in the amount invested at the initial public offering (IPO) of firms in the US and Europe. This study performs regressions on the relationship of patent applications before IPO and the amount of money collected at the IPO, while controlling other factors that may influence IPO performance. We also attempt to account for a potential source of endogeneity problems that can arise for self-selection bias and simultaneity between the number of patent applications prior to going public and the amount of money collected at IPO. We find significant and robust positive correlations between patent applications and IPO performance. The signalling power of patenting is significantly different for US and European companies, and is related to the difficulty in obtaining a signal and its scarcity. An additional patent application prior to IPO increases IPO proceeds by about 0.507% and 1.13% for US and European companies, respectively. Results suggest that a less ‘applicant friendly’ patenting system increases the credibility of patents as signals and their value for IPO investors.  相似文献   

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In traditional analysis of system performance, Markovian jump system is often considered in the full frequency domain. However, some unknown factors, such as noise interference, often act on a specific frequency domain, so there is a big defect in putting the system analysis in the full frequency domain. In this paper, the finite frequency domain is introduced into the Markovian jump system. By using generalized KYP lemma, the system is divided into three frequency bands: low, medium and high. The disturbance in different frequency domain is analyzed and the H filter is designed. In addition, in dealing with inequality relations, the improved Wirtinger inequality method is used, and the Projection lemma is used in dealing with filter coupling terms, and time-varying delay problem in finite frequency domain is also considered. Finally, some examples are given to illustrate the effectiveness of our methods and the specific parameters and convergence graph of the finite frequency domain filter are obtained.  相似文献   

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This paper deals with the input–output finite-time stabilization problem for Markovian jump systems (MJSs) with incompletely known transition rates. An observer-based output feedback controller is constructed to study the input–output finite-time stability (IO-FTS) problem. By using the mode-dependent Lyapunov–krasovskii functional method, a sufficient criterion checking the IO-FTS problem is provided. Then, an observer and a corresponding state feedback controller for the individual subsystem are respectively designed to solve the input–output finite-time stabilization problem for the systems. Finally, a numerical example on the mass-spring system model is investigated to bring out the advantages of the control scheme proposed in this paper.  相似文献   

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To perform repetitive tasks, this paper proposes an adaptive boundary iterative learning control (ILC) scheme for a two-link rigid–flexible manipulator with parametric uncertainties. Using Hamilton?s principle, the coupled ordinary differential equation and partial differential equation (ODE–PDE) dynamic model of the system is established. In order to drive the joints to follow desired trajectory and eliminate deformation of flexible beam simultaneously, boundary control strategy is added based on the conventional joints torque control. The adaptive iterative learning algorithm for boundary control scheme includes a proportional-derivative (PD) feedback structure and an iterative term. This novel controller is designed to deal with the unmodeled dynamics and other unknown external disturbances. Numerical simulations are provided to verify the performance of proposed controller in MATLAB.  相似文献   

10.
Increase in urine albumin excretion rate (AER) precede a fall in glomerular filtration rate in patients developing diabetic chronic kidney disease (CKD). Our results have shown that 7 (50 %) of diabetic and hypertensive individuals with decreased GFR do not have increased AER. In this cross-sectional study, we measured AER of 75 patients with type 2 diabetes and hypertension by immunoturbidimetric method. We correlated the results with eGFR values obtained by Cockcroft–Gault and MDRD method. The method used was not a compensated method. We measured serum creatinine by modified Jaffe’s kinetic method in autoanalyzer XL-600. Analysis of data showed positive correlation between eGFR and microalbuminuria by both the methods with eGFR <60 mL/min/1.73 m2. Pearson’s correlation co-efficient (r) was 0.9 (p = 0.0001) by Cockcroft–Gault formula and 0.69 (p = 0.0063) by MDRD formula. Our results concluded that there was positive correlation between AER and eGFR <60 mL/min/1.73 m2. We have recognized that these two parameters provide a complimentary benefit in management of cases with CKD.  相似文献   

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This paper develops a novel adaptive state tracking control scheme based on Takagi–Sugeno (T–S) fuzzy models with unknown parameters. The proposed method can deal with T–S models in a non-canonical form and allows the number of inputs to be less than state variables, which is more practical and has wider applications. The needed matching conditions for state tracking are relaxed by using a T–S fuzzy reference model to generate desired state reference signals. A new fuzzy estimator model is constructed whose states are compared with those of the T–S fuzzy model to generate the estimator state error which is used for the parameter adaptive law. Based on the Lyapunov stability theory, it has been proven that all the signals in the closed-loop system are bounded and the asymptotic state tracking can be achieved. The effectiveness of the proposed scheme is demonstrated through a magnetic suspension system and a transport airplane model.  相似文献   

13.

Given the affective psychological and cognitive dynamics prevalent during human–robot-interlocution, the vulnerability to cultural-political influences of the design aesthetics of a social humanoid robot has far-reaching ramifications. Building upon this hypothesis, I explicate the relationship between the structures of the constitution social ontology and computational semiotics, and ventures a theoretical framework which I proposes as a thesis that impels a moral responsibility on engineers of social humanoids. In distilling this thesis, the implications of the intersection between the socio-aesthetics of racialised and genderised humanoids and the phenomenology of human–robot-interaction are illuminated by the figuration of the experience of a typical black rural African woman as the user, that is, an interlocutor with an industry-standard socially-situated humanlike robot. The representation of the gravity of the psycho-existential and socio-political ramifications of such woman’s life with humanoids is abstracted and posited as grounds that illustrate the imperative for roboticists to take socio-ethical considerations seriously in their designs of humanoids.

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This paper focuses on the problem of HH filter design for continuous-time Takagi and Sugeno (T–S) fuzzy systems with time-varying delays. The partitioning time delay technique is used to construct the Lyapunov–Krasovskii functional, furthermore, a novel delay-dependent HH filter design approach is proposed based on the matrix decoupling approach, and the filter parameters can be obtained by solving a set of linear matrix inequalities (LMIs). The numerical examples show that the proposed method is of less conservativeness than the existing methods.  相似文献   

16.
This paper studies the problem of HH filtering problem for a class of nonlinear time-varying delay systems with unideal communication links. Two defectives are concerned including measurement quantization and packet dropouts. The quantized measurements are transmitted to the filter via network, where the phenomena of packet loss are taken into account. By using Lyapunov–Krasovskii functional, a less conservative delay-dependent stability condition for the closed-loop NCSs is derived. The HH fuzzy controller, which is designed in terms of linear matrix inequalities (LMIs), is developed for the asymptotic stabilization of the closed-loop NCSs. Numerical examples are given to illustrate the effectiveness of the proposed method.  相似文献   

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