A combined refrigeration and power cycle, which uses ammonia-water as the working fluid, is proposed by combining Rankine and vapour absorption cycles with an advantage of varying refrigeration capacity to power output ratio. The study investigates the usage of low temperature heat sources for the cycle operation. Results of parametric analysis are presented, which show the scope for optimizati...

A new formulation to easy simulation and optimization of gas and oil production systems is presented in this work. The problem of interest corresponds to the typical daily gas and oil production calculation, i.e. a one-day time period planning. The simulation problem considers determination of oil and gas production for the current topology. The optimization problem is established by considerin...

This paper presents a methodology to integrate life cycle assessment (LCA) in models used to design energy conversion systems. It is illustrated by an application to a thermo-economic model for the multi-objective optimization of synthetic natural gas (SNG) production from woody biomass. The life cycle inventory (LCI) is written as a function of the parameters of the thermoeconomic model. The o...

Demagnetization, commonly employed to study ferromagnets, has been proposed as the basis for an optimization tool, a method to find the ground state of a disordered system. Here we present a detailed comparison between the ground state and the demagnetized state in the random field Ising model, combing exact results in d = 1 and numerical solutions in d = 3. We show that there are important dif...

As DNA microarrays have been widely used for gene expression profiling and other fields, the importance of reliable probe design for microarray has been highlighted. First, the probe design for DNA microarray was formulated as a constrained multi-objective optimization task by investigating the characteristics of probe design. Then the probe set for human paillomavrius (HPV) was found using -mu...

In many practical problems, in particular in engineering design, the function form of criteria is not given explicitly in terms of design variables. Given the value of design variables, under this circumstance, the value of objective functions is obtained by real/computational experiments such as structural analysis, fluidmechanic analysis, thermodynamic analysis, and so on. Usually, these expe...

A global optimization based approach for nding all homogeneous azeotropes in multicompo-nent mixtures is presented. The global optimization approach is based on a branch and bound framework in which upper and lower bounds on the solution are reened by successively partitioning the target region into small disjoint rectangles. The objective of such an approach is to locate all global minima sinc...

an ab initio and density functional theory (dft) study about conformational analysis of tripeptide model hco−gly−l−ile−gly−nh2 is presented. the tripeptide was scanned about initial, central, and final residues, separately while for every scanning procedure the two other residues had been kept in the β conformation and side chain (sc) dihedral angles were maintained on the gauche− (g‾) state (χ...

abstract: minimizing the work consumed in refrigeration system is the most effective measure to reduce the cost of products in sub-ambient chemical processes. the introduction of mixed working fluids into refrigeration system in place of pure working fluids is a recent advancement applied in the field. due to the lack of systematic design method for mixed refrigerant cycle (mrc), conventional a...

quaternary ammonium compounds (qacs) are employed both as disinfectants for manual processing lines and surfaces in the food industry, and in human medicine area. qacs also cause cell death by protein denaturation . one of the qac is cetyl trimethyl ammonium bromide (ctab) that appears to rapture the cell membrane. the primary site of action of ctab has been suggested to be the lipid components...