Interregional Input-Output Optimization Model as a Tool for Evaluating the Efficiency of Large-Scale Railway Projects

2015 ◽  
Vol 138 (4) ◽  
Author(s):  
Dionysios P. Xenos ◽  
Erling Lunde ◽  
Nina F. Thornhill

This paper presents a framework which integrates maintenance and optimal operation of multiple compressors. The outcome of this framework is a multiperiod plan which provides the schedule of the operation of compressors: the schedule gives the best decisions to be taken, for example, when to carry out maintenance, which compressors to use online and how much to load them. These decisions result in the minimization of the total operational costs of the compressors while at the same time the demand of the plant is met. The suggested framework is applied to an industrial gas compressor station which encompasses large multistage centrifugal compressors operating in parallel. The optimization model of the framework consists of three main parts: the models of compressor maps, the operational aspects of compressors, and a maintenance model. The results illustrate the optimal schedule for 90 days and an example of the optimal distribution of the load of the compressors for 5 days. Finally, the results show the economical benefits from the integration of maintenance and optimization.


Author(s):  
Fumie Costen ◽  
Akos Balasko

The computational architecture of Enabling Grids for E-sciencE is introduced as it made our code porting very challenging, and the discussion presented is directly applicable to EGEE users. The final solution to the code poring problem is proposed, and its performance is examined. The solution to this problem be generally faced in the other large scale computation and so is applicable to users of other HPC facilities. This chapter gives a hint to those who have difficulties in applications with heavy data Input/Output (I/O) under the computational environment whose weak point is the data I/O.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jia Wu

PurposeThe study shows that with the progress of building technologies and building materials, the scale of buildings has increased. But in earthquake-prone areas, large-scale buildings mean higher risks; therefore improving the seismic capacity of buildings is an important measure to reduce the risk of buildings.Design/methodology/approachIn this study, the isolation structure of buildings was introduced briefly, and the cost-benefit based optimization model of the isolation structure was constructed. The optimization of the isolation structure was carried out from the perspective of benefit analysis. Then, two buildings with the same structure were analyzed as examples. One kept the original isolation structure, and the other optimized the isolation structure with the optimization model.FindingsThe final results showed that the optimized isolation structure had a lower input cost ratio, i.e. it had a higher benefit in the same whole life cycle, and the expected loss cost of the structure produced in the same life cycle was lower.Originality/valueIn conclusion, the optimization model of the isolated structure based on benefit analysis can effectively improve the benefit of building isolation structure produced in the whole life cycle.


Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 466 ◽  
Author(s):  
Jun Zhang ◽  
Denghua Zhong ◽  
Mengqi Zhao ◽  
Jia Yu ◽  
Fei Lv

Rockfill dams are among the most complex, significant, and costly infrastructure projects of great national importance. A key issue in their design is the construction stage and zone optimization. However, a detailed flow shop construction scheme that considers the opinions of decision makers cannot be obtained using the current rock-fill dam construction stage and zone optimization methods, and the robustness and efficiency of existing construction stage and zone optimization approaches are not sufficient. This research presents a construction stage and zone optimization model based on a data-driven analytical hierarchy process extended by D numbers (D-AHP) and an enhanced whale optimization algorithm (EWOA). The flow shop construction scheme is optimized by presenting an automatic flow shop construction scheme multi-criteria decision making (MCDM) method, which integrates the data-driven D-AHP with an improved construction simulation of a high rockfill dam (CSHRD). The EWOA, which uses Levy flight to improve the robustness and efficiency of the whale optimization algorithm (WOA), is adopted for optimization. This proposed model is implemented to optimize the construction stages and zones while obtaining a preferable flow shop construction scheme. The effectiveness and advantages of the model are proven by an example of a large-scale rockfill dam.


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