Sharif Digital Repository

A Lab-On-a-Chip (LOC) is a device which can integrate one or many laboratory functions on a small chip with millimeters to few square centimeters in size. LOC is a subset of MEMS devices and known as “Micro Total Analysis Systems” (µTAS) as well. LOC technology is closely related to microfluidics which primarily describes the physics, manipulation and study of minute amount of fluids.In this research we tried to simulate the performance of a microfluidic device for counting blood cells to find main factors of it for design and manufacturing. This research has two main sections, hydrodynamics of fluid inside the microchannels and finding electrical performance of designed Coulter counter for... 

Although existing literature on organizational culture and its change process contains meaningful and rich theories but our studies show that there is no perfect and detailed framework on linking organizational culture change and corporate entrepreneurship culture. In addition to that, Gamification –defined as taking the game design elements into non-game contexts– is a fruitful and academically rich research area. Fortunately an idea proposed recently to explain a method for enhancements in organizational culture in general, and in corporate entrepreneurship culture in particularby Yavari and Jafarian based on using game mechanisms. In their paper "A Gamification-Based Method for Corporate... 

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... 

The main objective of Control Engineering is to lead dynamic behavior of system to an arbitrary state, accomplishment of such an objective requires a model which somehow represents the dynamic behavior of the system, On the other hand an accurate yet fast and efficient model of a complicated model cannot be easily obtained based on the original inputs, states and outputs of the system. This is true both for mechanistic (white box) and empirical (black box) models. In this project, the previous frame work developed for object oriented plant-wide identification has been extended to cover the model reduction based on various established procedures in this area (e.g., statistical and intelligent... 

A modeling framework is proposed for complex chemical process networks. Concept such as passivity systems, thermodynamic function and graph theory are some important and applicable concept which seems to be useful for process network. The state is represented by energy, volume and mass inventories. The dynamic behavior of the process system is constrained so that all trajectories satisfy the first and second laws of thermodynamics. The concavity of the entropy function is used to define a storage function for passivity design. The proposed storage function is closely related to the Gibbs tangent plane condition. Stability analysis, pairing and controller design could be done by this new... 

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,... 

CCHP systems have attracted much attention in recent decades due to their economic and environmental benefits and high returns. Therefore, in this research due to the necessity of using high energy efficiency technologies and low cost of operation while also releasing minimum environmental pollutants such as carbon dioxide, a Solar-assisted CCHP system is studied. The performance of the CCHP systems is deeply dependent on the operation strategy of the system. In this research, in order to improve the techno-economic performance of the system, an optimization model is applied to optimize the proposed operation strategy using minimum distance methodology. In order to measure the proposed... 

Various solutions exist for managing the waste generated in the food industry, providing opportunities for industrial symbiosis. The objective of this project is to identify and economically evaluate these solutions for material and heat recovery in the dairy, sugar, and tomato paste industries. Quantities and qualities of the generated waste in the selected industries were first identified. Subsequently, opportunities for waste management were explored. The overall structure of each solution was then modeled, and economic variables such as costs and income in each opportunity were calculated. Economic indicators, including payback period, net present value, internal rate of return, return... 

Separation of biomolecules such as enzymes is the most important part of biotechnology process which 10-90 % of costs is for separation and purification. There are several methods for purification of bio materials and one of them is chromatography which use in enzyme purification but this method have several problem such as cost ,time consuming and scale up Because of this a suitable alternative demands for industrial separation. An alternative is aqueous two-phase systems (ATPS). In this project was studied about partial purification of alkaline protease produced by Bacillus licheniformis ATCC 21424 in aqueous two-phase system and comparison with chromatography method. an aqueous two-phase... 

In recent years, due to the energy price increase, great efforts were made to optimize the operating conditions of various chemical processes in order to reduce the operating cost and obtain the maximum possible profit. Decision makers should usually deal with different kinds of uncertainty in process optimization. In this situation, fuzzy optimization is an ideal method, since it represents and handles the underlying uncertainty of the optimization problems. In this paper, the optimization problem for production process of dimethyl ether (DME) as an alternative fuel to diesel is considered. Both crisp and fuzzy approaches are applied to formulate the optimization problem while sensitivity... 

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... 

A statistically-based method has been developed for automated identification of steady state. The method is computationally inexpensive when compared to conventional techniques. The R-statistic is dimensionless and independent of the measurement level. Because it is a ratio of estimated variances, it is also independent of the process variance. Simulations show that for recommended critical values are also effectively independent of the magnitude and distribution of the noise.
A fuzzy-logic-based methodology for on-line steady state and transient state identification is introduced. Although steady state identification is complicated by the presence of noise, fuzzy logic can help capture... 

Upstream Oil and Gas due to the high energy consumption offer multiple degree of freedom that can be exploited to reduce capital and/or operating costs. Be use combination of optimization methods (Retrofit and Operational Problems) due to the complex nature of the optimization in UOG. To achieve the optimization Details need to identify relationships between variables. System modeling based on demand in two categories, can be divided: the demand for water and oil based and model based on electricity demand. Existing and new technologies in both evaluated and identificated the application of the system in upstream sections. The linear programming model used to determine the export of...