Sharif Digital Repository

Since steady state behavior of a plant is affected by the change of various inputs to the plant, the transient behavior of the chemical plants are also very important in their general performance. On the other hand, catalytic hydrotreating is one of the most important processes in crude oil refining process in many aspects such as economical, technical and environmental. Thus, the goal of this project was dynamic simulation and control of catalytic hydrotreating unit (UNIFINER Unit) of Tehran Refinery with using the HYSYS software. To fulfill this target, data that were necessary for simulation were gathered from Unifiner unit of Tehran refinery at first. Then, steady state simulation of the... 

Traditionally, chemical Process design is focused on the selection of technologies and optimization based on economic consideration .In the 1970’s because of the global energy crisis, other consideration consider with economic goals .in this study we are eager to provide design procedures and guidance for optimizing chemical processes simultaneously based on economic and environmental aspects .this optimization is applied to production maleic anhydride(MA) from n-butane feedstock .an optimization algorithm based on the genetic algorithm with four decision variables(recycle flow ratio ,air to feed ratio ,solvent flow and reactor temperature ).for including dynamic objective in optimization... 

Application of the advanced control techniques and information technology in the biomedical engineering have been the focal point of the research communities in biomedical engineering due to the rapid growth of the nonlinear control theories along with the computer hardware. In this work the application of differential geometry and globally linearizing control has been applied to efficiently control the first phase of HIV disease based on the HIV infection model proposed in the literature. All the efforts have been in the way to obtain a suitable scenario of drug administration to suppress and control the infection. In the proposed scenario, drug administration is time dependant and... 

All living entities requires energy to continue their lives. In human beings this energy is provide through consumption of food, at first the consumed food gets converted to glucose and the produced glucose enters the blood and then goes to the body cells in which it is used to produce the required energy. The essential hormone which makes it possible to use Glucose for energy production is INSULIN. In the patients suffering from Type 1 Diabetes, lack of Insulin production makes it impossible for the cells to use Glucose for the production of their required energy. In these patients due to the fact that the blood Glucose is not used by the cells, the Blood Glucose Level (BGL) increases,... 

Nowadays diabetes is considered as one of the common diseases among mankind. Different body organs utilize the glucose or the sugar existed in various kinds of food as an energy source in order to provide required energy for their activities. Insulin hormone which is created by the pancreas gland has a very significant role in easing the respective procedure. Therefore, when the body is not capable of producing enough insulin, then glucose aggregation in the blood leads to higher blood sugar and thus a disease called diabetes type1. Up to now, considerable research activities have been done regarding the diabetes type1modelling. One of the bolded drawbacks of such models is that the effect... 

The abstract is the most important section of the thesis because many readers limit most of their reading to abstracts, saving in-depth reading for specific theses. It should give the reader a "preview" of what's to come. The abstract should emphasize new and important aspects of the study or observations. The purpose of the abstract is to allow researchers to decide whether or not to read the whole thesis. The abstract is what researchers read first to decide if the thesis is important, interesting, and it allows them to assess the relevance of a thesis to their own research, without having to read the entire thesis. Thus, it is crucial that the abstract both summarize succinctly the key... 

Many processes in the real world are multiple-input multiple-output (MIMO) systems. There are often some interactions between the inputs and outputs. In the other words, every input affects on several outputs, and every output is affected by several inputs. In order to control of these systems, we usually desire to decouple the loops into multiple non-interacting SISO systems after proper pairing of manipulated and controlled variables. Loop interactions can destabilize a control system, so tuning controllers in an interacting MIMO system can be difficult. Decoupling problem has been discussed in the two domains: linear control and nonlinear control. However, both of them need an exact model... 

In this thesis, the latest human respiratory system is extended such that it addresses the effect of blood acidity on the performance of the human respiratory system. Since the model does not take into account any controller, two PI controllers proposed by Bental have been used to simulate the closed loop behavior of the respiratory system. Since, in the original model blood pH is considered as a constant value, the extended model has been used for the case where the blood pH pumped by heart is assumed to be and the obtained results have been compared with those of the original model. The similarity of the results shows the extended model to be valid for the normal case. Model since t he... 

Mathematical models are used for describing physical systems to make it possible to study and investigate the behavior of these systems and compare their performance and improve them. For this reason, a mathematical model for cardiovascular system and respiratory system is used to study how these two systems interact. The cardiovascular system model and the respiratory system model comprise four and two compartments, respectively. In fact, the combined model contains the left and right ventricles, body tissue, lung, systemic blood circulation, and pulmonary compartments. Heart rate and alveolar ventilation are assumed to be the quantities through them the central nervous system controls the... 

Due to continuous improvements in manufacturing and the fact that modern technologies such as microprocessors, are becoming more efficient along the rapid growth of nonlinear control methods usage, the application of these two tools together has entered various fields of biomedical engineering, particularly neural prostheses. In this study, the methods of analysis and control of nonlinear systems were used to investigate and improve the behavior of the neural breathing system on the basis of Hodkgin-Huxley model as the original model of the neuron. Using the principles of differential geometry and robust control methods – based on combination of exact input-output linearization ideas,... 

A steady laminar flow coupled with heat transfer and chemical reaction corresponding to metalorganic chemical vapor deposition (MOCVD) in an axis-symmetrical rotating disc reactor has been simulated in a detail manner based on Computational Fluid Dynamics approach. The simulation results have been validated with the benchmark solutions obtained from the literatures for the corresponding casestudy.Three decision variables have been used whose optimum values are sought inorder to minimize the nonuniformity of the film on the susceptor. Their optimum values have been obtained by the elder-Mead algorithm which is a geometric optimization method which does not require gradient of the objective... 

Three different feedback linearization control methods are applied to nonlinear control of type I diabetes mellitus model. One is exact FBL and the two others are approximate manners based on approximations of the nonlinear system and its duality one-form, utilizing uniform approximation and a homotopy operator, respectively. An extended luenberger observer is also employed to observe the required states of designed compensators. The nonlinear compensators are designed based on a minimal model and applied to the minimal model, as well as Sorensen’s physiological model. In addition to the mentioned close-loop control strategies, a discrete control strategy based on an optimization problem is... 

Nowadays, one of the most challenging issues concerning the manufacturing industries is the shortage of available resources and their increased costs. As a matter of the fact, for these industries, optimizing the processes is not something to be ignored and one of the most important goals is reducing the costs of manufacturing and increasing the profits of sales. On the other hand, in actual situations, due to the complexities of optimization problem and numerous calculations, the classical methods would be limited to very simplistic cases in which most of the practical changes are ignored. In such problems, the need to use strong optimization techniques like the genetic algorithm is evident... 

In this thesis, in the first step, design of an Agent Based framework was accomplished. Agent oriented programming is a kind of programming based on distributed processing by agents in a same location or not. UML was used to design the the agent based framework. To implement the designed framework, C++ programming language was used. Embarcadero C++ Builder IDE was chosen to implement the design. Then the designed framework was used to develop a sofware for data reconciliation. The branch for dynamic data reconciliation of this project was extended. To validate the ability of the sofware, a distillation column model with 7 states was selected. The result of gross error detection and data... 

Inherent safety means that the process is naturally safe and the conditions of occurrence of unsafe cases and situations are eliminated from the system so that unsafe conditions can be controlled and prevented from occurrence by means of layers of protection. In general, evaluation of inherent safety may be studied in two different conditions; the first one is associated with the units that are not completely designed and built yet. In the initial steps of developing a process, there is much freedom in the determination of materials, equipment, and designing variables. As soon as the process enters its life cycle, making changes in the process will be very difficult and expensive. Therefore,... 

In this work steady state and dynamic performances of quaternary distillation column sequences designed based on steady state and dynamic cost functions have been investigated. To quantify the dynamic performance, product loss due to disturbances has been considered in the objective function. In addition, variations of operating costs such as utilities have been considered in the objective function. To separate a quaternary mixture into four products, twenty two configurations have been used. It has been observed that the feed composition, disturbance frequency and magnitude affect the dynamic behavior strongly. To decrease the optimization computational load, a scheme that provides a... 

In this study, a tree-dimensional random pore-scale network model is used to simulate the membrane contactor porous medium. Drainage and imbibition phenomena is simulated to have a better knowledge of liquid and/gas intrusion trough the membrane porous structure. A genetic algorithm is used as an optimization tool. Several variables such as the number, radius and location of pores, the coordination number, as well as the radius and length of the throats are used herein as the optimization parameters. The difference between the binary SEM images and virtual sections on the generated network in conjunction with the permeability and mean pore size data were selected as the objective function.... 

Oil reservoirs, have integrated identity; that is they consist of different parameters such as wettablity, initial water saturation, capillary and gravity forces, etc. which are related to each other and affect ultimate recovery simultaneously. In fractured reservoirs, other parameters such as fractures and complex geological structures are also considered  among  important  parameters  which  affect  ultimate  recovery.  Due  to  large  amount  of reserves,  fractured  reservoirs  are  subject  to  different  studies  and  simulations.  In  this  research, different  parameters  which  affect  ultimate  recovery  in  fractured  reservoirs,  are  studied  and simulated. Different  studies ... 

Access to a reduced and fast mathematical model that can predict the input-output behavior of interconnected systems with acceptable accuracy and in a short time is crucial. The purpose of this project is to provide an object-oriented platform for identifying a model based on input-output data of interconnected systems in real-time. On this basis, in the case of developing fast estimation algorithms and updating the model quickly (in case of extensive changes in the system), good predictions of the model can be used for various applications. In this research, machine learning and data analysis methods are used to extract useful features and relations from data. Then, taken advantage of this... 

Compact linear accelerator is equipped with a single fixed motorized wedge that produces different wedge angles by combining an open and a wedged field in the appropriate proportions.
In this work, the required data for the Treatment Planning System, TPS were generated for utilizing Compact motorized wedge, MW and was verified by dosimetry. To verify MW, the accumulated wedge profiles at a depth of 10 cm for different wedge angles were measured using 2-D Profiler and were calculated the wedge angles using an analytical formula. The validity of effective wedge angles 2-D Profiler has been done by determining the wedge angles in accordance with ICRU-24 for compact MW and Telecobalt...