Heat exchangers are the critical components of refrigeration and liquefaction processes. Selection of appropriate operational conditions for cryogenic recuperative heat exchanger and expansion valve operating in Joule-Thomson cooling system results in improving the performance and efficiency. In the current study, a straightforward procedure is introduced to design an efficient Joule-Thomson co...

a central aim of educational research in the area of mathematical modeling and applications is to recognize the attainment level of students at defined states of the modeling process. in this paper, we introduce principles of fuzzy sets theory and possibility theory to describe the process of mathematical modeling in the classroom. the main stages of the modeling process are represented as fuzz...

In this paper we develop and analyze the model for the spread of Leptospirosis by age group in Thailand, between 1997 and 2010 by using mathematical modeling and computer simulation. Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. It is a zoonotic disease of global importance and an emerging health problem in Thailand. In Thailand, leptospirosis is a reportable diseas...

water quality aspect with regard to dissolved oxygen was studied for a 24 kilometer stretch of malaprabha river in karnataka state, india. main objective of the research was to simulate the predicted dissolved oxygen depletion due to the waste load allocation in the river with the ambient observed values of dissolved oxygen, and to ascertain the application of mathematical modeling for predicti...

Nowadays, membrane processes are widely used for high purity Nitrogen production. Separation of air by membranes is a flexible process in which the investment and operational costs are lower than for example adsorption or cryogenic processes. Such processes are based on relative permeability of air components which are transported by the pressure difference between two sides of the membrane. M...

A general mathematical description of the terminal behavior of subsystems is discussed. It allows to combine different modeling methods, e. g. network models, block models, and bondgraphs together. The resulting equations can be solved with a general network analysis program. This approach is effectively applied in modeling electrical as well as non-electrical subsystems. Extensions to digital ...

The power supply of remote sites and applications at minimal cost and with low emissions is an important issue when discussing future energy concepts. This paper presents modeling and optimization of a photovoltaic (PV)/wind/diesel system with batteries storage for electrification to an off-grid remote area located in Rafsanjan, Iran. For this location, different hybrid systems are studied and ...

The ability of cancer cells to break out of tissue compartments and invade locally gives solid tumours a defining deadly characteristic. One of the first steps of invasion is the remodelling of the surrounding tissue or extracellular matrix (ECM) and a major part of this process is the over-expression of proteolytic enzymes, such as the urokinase-type plasminogen activator (uPA) and matrix meta...