An integrated MCDM approach to evaluate public transportation systems in Tehran

Public transportation is one of the most important systems in transportation, especially in big and crowded cities. As a result, evaluation of public transportation systems is a strategic decision-making problem for both private and public sections. In this paper, the problem of public transportation passengers in Tehran is addressed and their satisfaction levels are assessed by using passenger satisfaction survey. An integrated MCDM approach is proposed for evaluation of public transportation systems based on Delphi method, group analytic hierarchy process (GAHP) and preference ranking organization method for enrichment of evaluations (PROMETHEE). The proposed model provides more reliable and realistic results and introduces directions for future improvements of public transportation service quality. A sensitivity analysis is applied to investigate the influence of criteria weights on the decision making problem. As a conclusion, the most important public transportation systems in Tehran orderly are: metro, taxi, BRT, bus and van. Therefore, Tehran Municipality and policy makers should encourage and support the previously mentioned systems

Febril konvülsiyonda serum çinko düzeyleri: Eksiklik gerçekten bir risk faktörü müdür?]

Objective: Pathogenesis of febrile seizures is still unknown, despite it is the most common type of seizures and one of the leading neurologic disorders of childhood. Trace elements and especially zinc deficiency is suggested to be the trigger factor for convulsions. In the present study, we aim to determine the possible relationship between zinc and febrile seizures. Material and Methods: 60 patients are included as study group, aged between 3 months and 5 years old and with febrile seizures. In first control group, 30 patients with fever but no convulsions aged between 3 months and 5 years old are choosen. In second control group, 30 patients with no health problems are choosen. Serum zinc levels are determined in first 12 hours after admission. Data are evaluated with SPSS 10.0 programme. Results: Mean zinc levels of patients with febrile seizures was found 153.43±47.92 mg/dL, and mean zinc levels of 1. control group and 2. control group was found 108.93±33.91 mg/dL and 121.4±53.29 mg/dL respectively. Mean serum zinc levels of the study group was found statistically higher from both of the control groups. There was no relationship between serum zinc levels and age, gender, weight, temperature level, number and etiology of convulsions and family history. Conclusion: We found no relationship between serum zinc levels and febril seizure, despite the previous studies. Copyright © 2012 by Türkiye Klinikleri

A simulated annealing approach to mine production scheduling

© 2005 Operational Research Society LtdIncreasing global competition, quality standards, environmental awareness and decreasing ore prices impose new challenges to mineral industries.Therefore, the extraction of mineral resources requires careful design and scheduling. In this research, simulated annealing (SA) is recommended to solve a mine production scheduling problem.First of all, in situ mineral characteristics of a deposit are simulated by sequential Gaussian simulation, and averaging the simulated characteristics within specified block volumes creates a three-dimensional block model.This model is used to determine optimal pit limits.A linear programming (LP) scheme is used to identify all blocks that can be included in the blend without violating the content requirements.The Lerchs–Grosmann algorithm using the blocks identified by the LP program determines optimal pit limits.All blocks that lie outside of the optimal pit limit are removed from the system and the blocks within the optimal pit are submitted to the production scheduling algorithm.Production scheduling optimization is carried out in two stages: Lagrangean parameterization, resulting in an initial sub-optimal solution, and multi-objective SA, improving the sub-optimal schedule further.The approach is demonstrated on a Western Australian iron ore body.M Kumral and PA Dow