In this Book we consider the problem of modeling the dynamics of the Immune system during and after a solid organ transplantation, taking into consideration the pharmacodynamics of different therapeutic drugs Immunosupressants like "Cyclosporine" and "Thymoglobulin" at different doses during the Grafts lifespan which affect the dynamics of the Cellular and Humoral pathways of the Immune systems. The proposed model extends the Gaetano et al.'s model considering both the Cellular and Humoral Pathways. Some preliminary results of a numerical simulation are given proving that the model behaves as predicted by physical tacticians.
The main objective of this book is to control indoor temperature and reject faults tolerant like sensor deterioration, noise, disturbance and depreciation of the plant in building air conditioning system; we propose a fault tolerant controller system (FTCS) strategy for temperature control of air-conditioning system. The set-point response controller in the FTCS is designed in terms of insusceptible with noise, failure sensor, disturbance and parameter variation with optimal performance specification. The output of system was predicted through indoor, outdoor disturbance, at last based on the mathematical model of air-conditioning space. According to the system operation requirement for faults rejection, a closed-loop for rejecting faults signals is configured. It is found that the set-point response, the disturbance rejection, the noise rejection, the robust, rejection of failure sensor and the performance of the designed FTCS are better. Therefore the residual signal can now be used to monitor faults in the system while the proposed method ensures correctness of operation. Furthermore, FTCS has achieved the desired indoor temperature, superior performance, adaptation, robustness.
Although viscoelastic flows are characterized by a very low Mach number regime, it involves a weakly compressible liquid phase, which requires a special treatment. This work is devoted to the mathematical modeling and numerical simulation for viscoelastic fluids. It follows directly a previous publication, PhD dissertation of the author. A Unified purely hyperbolic mathematical model for compressible and incompressible viscoelastic fluids is presented. To complete the mathematical model, a complete chapter is devoted to describe a new procedure to determine the correct type and number of boundary conditions for hyperbolic systems. Then a new model describing the non-isothermal viscoelastic flows is introduced while keeping the hyperbolic nature of the system. The main advantage of the proposed model over the existing ones is its hyperbolic nature, which overcomes some of the drawbacks of the available models. The proposed model is then solved numerically using a hybrid finite element/finite difference scheme.
In the book an attempt has been made to develop some new diagnostic tests for statistical model building in the context of linear regression models. Diagnostics of outliers has been described and a test for identifying outliers by using predicted residuals has been proposed in the present study. Besides outliers, a measure of influence for diagnostics has been developed in the study. Some new modified R2 and criteria for model selection have been developed along with modified mean square prediction error criteria; and modified information criteria for model selection. A test for exogeneity in model specification by using augmented regression model; and a test for stability of regression parameters in model specification have been proposed under diagnostic tests. A new test for misspecification of the linear regression model has been derived along with a modified Rainbow Test by using Internally studentized residuals. The problem of misspecification of non-nested linear regression models, has been discussed together with a diagnostic test for functional form between loglinear and linear regression models.
Designing a well-integrated public transit system and improving the cost-effectiveness network, public transport could play a crucial role in passenger satisfaction and reduce operating costs. The main objective of this research is to develop a mathematical formulation model for designing and coordinating schedules of integrated public transit services, which includes the development of feeder services and coordination with major transportation services and transfer time consideration between two modes (i.e. Feeder bus and LRT). In the proposed improved model, the additional terms and constraints employed in objective function provide more accurate and efficient solutions for various conditions of transit systems and this may lead to the creation of a more realistic model in simulating real-life problems. In this study, optimized transit services and coordinated schedules are developed using metaheuristic algorithms. Obtained numerical results of the proposed model including optimal solution, statistical optimization results, the convergence rate as well as comparisons were discussed in detail.
Knowledge of the characteristic of photovoltaic PV module is a prerequisite for designing and dimensioning a PV power supply. This is the reason for the development of PV module models useful for electrical applications. This approach allows the development of a high-performance conversion systems balancing system-components and permitting the evaluation of the behaviour of the entire system in various scenarios. Seven variables studying model was proposed in this book as a simple method of modelling and simulation of photovoltaic module using Matlab software package. The method is used to determine the characteristic of PV module and to study the influence of different values of solar radiation at different temperatures concerning performance of PV cells. Taking the effect of Irradiance and temperature and wind speed into consideration as environment effects and Saturation Current, Ideal Factor, Series and Shunt resistances as a four inside construction variables, the output current and power characteristic of photovoltaic module are simulated using the proposed model.
This book proposes an infrastructure for modeling the architecture of a software system by adapting existing architectural languages, viewpoints and frameworks to domain- and organization-specific features. Under this perspective, the proposed infrastructure allows architects to set up customized architectural frameworks by: (i) defining and choosing a set of viewpoints that adequately fit with the domain and features of the system being developed, (ii) automatically adapting existing architecture description languages to project-specific concerns, (iii) keeping architectural views within the framework synchronized, (iv) enabling consistency and completeness checks based on defined correspondences and rules among architectural elements. The proposed approach builds upon the conceptual foundations of ISO/IEC/IEEE 42010 for architecture description and it is generic with respect to the used architectural elements (i.e., views, viewpoints, languages, stakeholder’s concerns, etc.). The proposed approach is realized through a combination of model transformations, weaving, and megamodeling techniques. The approach has been evaluated in the context of a real complex system.
The present dissertation presents a pioneer study in what concerns the Portuguese Twitter community analysis and a new system to build real-time datasets from Twitter. During the dataset creation phase we built a system to crawl data from Portuguese Twitter users. This system, TwitterEcho, allows a complete and continuous crawling process, robust enough to support the whole Portuguese community on Twitter. Throughout this dissertation we describe the system implementation details, with more incidence on the client part, since it is a distributed system. Additionally, we present the results of studies done with data retrieved by the system. After, we present the influence model proposed in this dissertation. The model was developed based on models described in the literature or used in commercial applications. We detail the processes of gathering the metrics used to influence measurement. This involves the application of data-analysis techniques to the content produced by Twitter users. Finally, we show the results obtained by the model after its application on a dataset created from TwitterEcho. we also present a preliminary validation of the model, and future ways to validate it.
With an eye to prevent derailment of high speed trains, vis-a-vis unwarranted loss of lives and property, a formalism is developed. A software model of Rolling Contact Fatigue (RCF) crack propagation in railway tracks is designed, simulating the alarming stress intensity factor around the advancing fatigue cracks. RCF crack monitoring system with acoustic emission count signals, describing the damage threshold of railway tracks is designed. It is noticed through the model that the observed Acoustic Emission (AE) count at a particular instant of time in a specific location of railway track is a true indication of the vulnerability of rail failures. Further to provide hardware validation, a novel method using the intensity of back scattered light is implemented. In view of difference in the intensity of back scattered light from surface irregularities, a model is developed to find out the threshold intensity of scattered light that ensures safety in the railway system against fatigue failure. The proposed model, a completely new of its kind bears a high socio-technological value as it entails the design of an intelligent control system to prevent train accidents.
Piezoelectric systems are widely employed in precision engineering and the capability for precision tracking at broadband frequencies is increasingly appealing. However, the performance of dynamic tracking is limited over a wide range of frequencies, because of the coupled hysteresis, creep, and vibration dynamics. This book thus presents the modeling and control of piezoelectric systems over a broad range of frequencies. The mathematical and physical modeling are proposed as well as the model-based feedforward and several feedback approaches. This book is suitable for graduates and researchers in precision engineering, especially interested in high-speed and precision motion of instruments.
Currently various collection strategies are implemented in different parts of the world to collect End-of-Life (EOL) products. Since different collectors in the reverse logistics network will influence the performance of a collection strategy, a suitable collection program is required. The objective of this research is to find an optimum collection strategy to suit various environments by considering the costs and the environmental aspects of collection. To design optimum collection strategies, information on the rate of EOL product returns is essential. Therefore, a methodology is proposed to forecast the return of EOL products by considering product life, consumer behaviour and historical sales. This forecast model is then integrated into the collection strategy model. The integrated model is dynamically formulated to present the behaviour of different sets of strategies. Coloured Petri Net (CPN) approach is utilised in the forecasting and modelling of collection strategies. The results indicate that the integrated model will help practitioners in making decisions on implementing a suitable collection strategy for Reverse Logistics.
With the advent of ubiquitous computing environments it has become increasingly important for applications to take full advantage of Context aware computing to increase the satisfaction of the users in context aware environment services. Also with the increasing amount of research on Interactive Context Aware Applications like Context Aware TV, Context Aware Mobile, Context Aware Living Room, etc, users are interacting with them in an ever more convenient way. Currently, the programming of context-aware applications is complex and laborious. Even though the number of context aware applications is increasing day by day along with the users, till today there is no generic modeling and programming paradigm for context aware applications. This situation could be remedied by design and developing the appropriate modeling as a base for context aware programming paradigm. The book discusses the basic version of different types of proposed context oriented modeling approach for facilitating the programming of user context aware applications or in general context aware applications. Each type of modeling technique is explained using the proposed set of graphical notations and diagrams.
The mixture of two regression regimes has been extensively studied in economics. The test of a mixture of regimes in hazard modeling would be seen to have fundamental importance in biostatistical research but has not been studied. A two-regime parametric mixture is proposed to model the effect of a single covariate on the event time. Typically, the Cox proportional hazards model is applied to estimate a single regime survival regression function. The mixture of two regimes model contains five parameters to be estimated; namely, two parameters to describe each regime, and one to describe the mixing proportion. A software program developed for this research finds the maximum likelihood estimates of the parameters and the likelihood ratio test of the null hypothesis of a single regime against the alternative of a mixture of two regimes. A simulation study finds an approximation to the null distribution of the test and its approximate power.
The proposed analytical model developed for concrete confined by FRP composite jackets, might become useful document for various designers and researchers working in the field of retrofitting. Results given by this model easily accepts with the one obtained from the experimental results. The model suggests that, lateral confinement of concrete with FRP composite jackets increases the strength and ductility, under uniaxial compressive load.
Within this work is the presentation of a general 3D model capable of capturing the multiaxial behavior of superelastic shape memory alloys (SMAs) under quasi-static isothermal or dynamic loading conditions. A semi-analytical framework is developed to numerically implement the model. An extended experimental study is conducted on NiTi thin walled tubes to investigate the performance of the model. The proposed approach is shown to be able to capture the non-Mises thermomechanical response of NiTi under complex tension-torsion loading conditions. The effect of loading sequence and loading rate is also experimentaly studied. The main motivation of the present study is to develop a platform for analyzing and designing biomedical devices with SMA actuator under combined tension-torsion loading conditions. The torsional stiffness of NiTi is shown to be adjustable by applying an extra axial load. This will lead to developing desirable torque response in NiTi tubes and rods by varying the axial load. A possible application of this technique in the form of an assistive device is discussed.