Robust Controller Design of Networked Control Systems with Nonlinear Uncertainties

We address robust stabilization problem for networked control systems with nonlinear uncertainties and packet losses by modelling such systems as a class of uncertain switched systems. Based on theories on switched Lyapunov functions, we derive the robustly stabilizing conditions for state feedback stabilization and design packet-loss dependent controllers by solving some matrix inequalities. A numerical example and some simulations are worked out to demonstrate the effectiveness of the proposed design method.

Measuring internal market orientation

Internal marketing has been discussed in the management and academic literature for over three decades, yet it remains ill defined and poorly operationalized. This paper responds to calls for research to develop a single clear understanding of the construct, for the development of a suitable instrument to measure it, and for empirical evidence of its impact. Existing, divergent conceptualization of internal marketing are explored, and a new, multidimensional construct, describing the managerial behaviors associated with internal marketing is developed, and termed internal market orientation (IMO). IMO represents the adaptation of market orientation to the context of employer-employee exchanges in the internal market. The paper describes the development of a valid and reliable measure of IMO in a retail services context. Five dimensions of IMO are identified and confirmed. These are 1) formal written information generation, 2) formal face-to-face information generation, 3) informal information generation, 4) communication and dissemination of information, and 5) responding to this internal market information. The impact of IMO on important organizational factors is also explored. Results indicate positive consequences for customer satisfaction, relative competitive position, staff attitudes, staff retention and staff compliance.

Source location of acoustic emission waves for structural health monitoring of bridges

The process of structural health monitoring (SHM) involves monitoring a structure over a period of time using appropriate sensors, extracting damage sensitive features from the measurements made by the sensors and analysing these features to determine the current state of the structure. Various techniques are available for structural health monitoring of structures and acoustic emission (AE) is one technique that is finding an increasing use. Acoustic emission waves are the stress waves generated by the mechanical deformation of materials. AE waves produced inside a structure can be recorded by means of sensors attached on the surface. Analysis of these recorded signals can locate and assess the extent of damage. This paper describes preliminary studies on the application of AE technique for health monitoring of bridge structures. Crack initiation or structural damage will result in wave propagation in solid and this can take place in various forms. Propagation of these waves is likely to be affected by the dimensions, surface properties and shape of the specimen. This, in turn, will affect source localization. Various laboratory test results will be presented on source localization, using pencil lead break tests. The results from the tests can be expected to aid in enhancement of knowledge of acoustic emission process and development of effective bridge structure diagnostics system.