A Sequential Framework for Heat Exchanger Network Synthesis (HENS) is presented. The network generation and optimization phase of the framework, one of its core subproblems, is presented with details as to the source of the non-convexities in the model. Physical insight based automated starting value generators are developed to ensure that the base NLP formulation solves to a ‘good’ local optim...

Some oil refineries arrange low-fusion-point crude oil storage tanks and ones containing high-fusionpoint crude oil at two diverse locations. Refinery needs different pipeline to transport different fusion point oil, so, to transport diverse fusion point oil it needs two pipelines. Because of the constraints resulted from transporting high-fusion-point oil, to schedule such a system is very har...

abstract background: the use of coping strategies in reducing the adverse effects of stress can be helpful. nero‑linguistic programming (nlp) is one of the modern methods of psychotherapy. this study aimed to determine the effect of nlp on occupational stress in nurses working in critical care units of urmia. materials and methods: this study was carried out quasi‑experimentally (before–after) ...

pumps are among the early instruments invented by humans to be taken advantage of in the use of water utilities. design and operation problem of pumping stations is a type of mixed integer non linear programming, in which gradient based optimization methods are not efficient for solving complex problems of this type. in this regard, such evolutionary optimization algorithms as genetic algorithm...

• Dynamic performance under various forms of disturbances. Nonlinear programming formulation for dispatch virtual inertia and damping. Semi-definite relaxation to address non-convexity. Clique decomposition approach exploit sparsity. Distributed solution based on the alternating direction method multipliers. Power grids are evolving toward 100% renewable energy interfaced by inverters. Virtual ...

W consider the network loading problem (NLP) under a polyhedral uncertainty description of traffic demands. After giving a compact multicommodity flow formulation of the problem, we state a decomposition property obtained from projecting out the flow variables. This property considerably simplifies the resulting polyhedral analysis and computations by doing away with metric inequalities. Then w...

This article presents the formulation and the solution of a class of Mixed-integer Nonlinear Programming (MINLP) problems, applied to optimal synthesis of process systems in a modular simulator environment. The proposed algorithm makes use of module, reduces the work of calculation on model equations, makes the size of MINLP smaller. The algorithm consists of solving alternate sequences of MILP...

With predefined schedule, this paper presents a mathematical formulation for synthesis of water-using networks in batch plants with a central reservoir for targeting freshwater consumption. A superstructure that considers all water reuse/recycle possibilities is presented for modeling the time-dependent water-using network. The proposed superstructure-based representation for synthesis of batch...

We develop a trust region filter strategy for simultaneous optimal design of heat exchanger networks that includes detailed shell-and-tube exchangers. The first solves mixed-integer nonlinear programming (MINLP) formulation with shortcut models to generate candidate network topologies, which are then used in non-isothermal mixing (NLP) suboptimization embedded using modified (TRF) algorithm. An...