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1.
J Contam Hydrol ; 265: 104385, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878553

RESUMO

This study aims to develop a multi-objective quantitative-qualitative reservoir operation model (MOQQROM) by a simulation-optimization approach. However, the main challenge of these models is their computational complexity. The simulation-optimization method used in this study consists of CE-QUAL-W2 as a hydrodynamic and water quality simulation model and a multi-objective firefly algorithm-k nearest neighbor (MOFA-KNN) as an optimization algorithm which is an efficient algorithm to overcome the computational burden in simulation-optimization approaches by decreasing simulation model calls. MOFA-KNN was expanded for this study, and its performance was evaluated in the MOQQROM. Three objectives were considered in this study, including (1) the sum of the squared mass of total dissolved solids (TDS), (2) the sum of the squared temperature difference between reservoir inflow and outflow as water quality objectives, and (3) the vulnerability index as a water quantity objective. Aidoghmoush reservoir was employed as a case study, and the model was investigated under three scenarios, including the normal, wet, and dry years. Results showed the expanded MOFA-KNN reduced the number of original simulation model calls compared to the total number of simulations in MOQQROM by more than 99%, indicating its efficacy in significantly reducing execution time. The three most desired operating policies for meeting each objective were selected for investigation. Results showed that the operation policy with the best value for the second objective could be chosen as a compromise policy to balance the two conflicting goals of improving quality and supplying the demand in normal and wet scenarios. In terms of contamination mass, this policy was, on average, 16% worse than the first policy and 40% better than the third policy in the normal scenario. In the wet scenario, it was, on average, 55% worse than the first policy and 16% better than the third policy. The outflow temperature of this policy was, on average, only 8.35% different from the inflow temperature in the normal scenario and 0.93% different in the wet scenario. The performance of the developed model is satisfactory.


Assuntos
Modelos Teóricos , Qualidade da Água , Abastecimento de Água , Algoritmos , Simulação por Computador
2.
J Health Psychol ; 21(12): 2977-2982, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26150431

RESUMO

A total of 64 pregnant women were assigned into two groups of cases and controls. Both groups filled out the Perceived Stress Scale at pre-test. Cognitive-behavioral coping skill training was delivered to the case group. After the end of the intervention, both groups completed the same scale again. The results showed that the mean perceived stress of the cases and controls was 27.77 ± 6.033 and 18.97 ± 3.268, respectively (p = 0.001). Therefore, midwives are recommended to plan educational interventions to decrease perceived stress in pregnant women.


Assuntos
Adaptação Psicológica , Terapia Cognitivo-Comportamental/métodos , Complicações na Gravidez/prevenção & controle , Gestantes/psicologia , Cuidado Pré-Natal/métodos , Estresse Psicológico/prevenção & controle , Adulto , Feminino , Seguimentos , Humanos , Percepção , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/psicologia , Estresse Psicológico/diagnóstico , Estresse Psicológico/psicologia , Resultado do Tratamento
3.
Iran Red Crescent Med J ; 15(11): e11741, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24719682

RESUMO

BACKGROUND: To assess maternal confidence in her ability to cope with labor, a measure of childbirth self efficacy is necessary. OBJECTIVES: This paper aims to assess the cultural adaptation and psychometric testing of the short form of childbirth self-efficacy Inventory among Iranian pregnant women. PATIENTS AND METHODS: In this descriptive-methodological study, we investigated 383 Iranian pregnant women in the third trimester. They were recruited from the outpatient prenatal care clinic of Taleghani Hospital and an urban health center from August to November 2011. Content validity was evaluated by a panel of specialists after adding two religious items. The women completed the inventory and the demographic characteristics questionnaire in an interview room. The internal consistency and construct validity were assessed by Cronbach's alpha and by exploratory and confirmatory factor analyses, respectively. Known group analysis on gravity assessed the discriminant validity of the measure. RESULTS: Content validity of the short form of the Iranian childbirth self-efficacy Inventory was confirmed. Factor analyses supported the conceptual two-factor structure of measure and hence supported its construct validity. The internal consistency was approved for the total scale and both subscales. The instrument differentiated prim gravid from multigravida women in the total scale and the efficacy expectancy subscale. CONCLUSIONS: Validity and reliability of the measure supports the use of the short form of the instrument as a clinical and research instrument in measuring childbirth self-efficacy among Iranian pregnant women.

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