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Power flow (PF) is in one of the most studied non-linear problems related to power systems which heavily affects security issues such as generation cost, voltage stability and active power loss. In this paper, a simple and new approach based on artificial neural network (ANN) and differential search (DSA) algorithm has been proposed and applied for one of the most complex problems in power systems, Power Flow (PF) problem. By using the proposed DSA implemented ANN method, IEEE 9-bus, IEEE 30-bus and IEEE 118-bus test system parameters are obtained without running iterative convergence methods such as Gauss-Siedel or Newton-Raphson. By comparing with several most used non-linear iterative methods, the results obtained using the classical training method and proposed DSA implemented hybrid training methods are presented and discussed. Obtained results in this work show that the ANN based power flow method can be implemented to solve non-linear static and dynamical problems concerning power systems successfully.

The aim of this study was to determine the direct and indirect effects of factors affecting land prices. The data of the study were collected through questionnaires in Ladik District of Samsun Province, Turkey in 2018. In the study, the factors that directly and indirectly affected the price of land were determined by using path analysis. While the factors that affected land price positively were yield and irrigation, the factors that affected land price negatively were stoniness, slope and distance from village and main road. The most important variable that affected land price directly was the distance from the main road (60%), the variable that most affected land price indirectly was stony soil (69%). The direct effect of yield on the land price was 44% and the indirect effect was 56%. The direct effect of irrigation was 38% and the indirect effect was 62%. The study also determined that 45% of the indirect effect of irrigation was due to increased productivity. Explaining the direct and indirect effects of the factors affecting the land price will make a significant contribution to scientific and objective land valuation studies. In addition, the results obtained can be used as an auxiliary element for land valuation methods.

Human Performance Technology (HPT) is the applied study and practice of improving organizational performance through training and non-training interventions. For practitioners working in this area that identify themselves as an HPT practitioner, organizational training and performance (OTP) specialist, or instructional designer--offering the right intervention set requires understanding of how humans work and function internally and within organizations that are bounded by environmental, societal, and economic realities. The HPT field is rooted in a multi-disciplinary knowledge base and has its own models and theories, which are generally developed by practitioners to guide their practice. Because HPT follows a systematic, data-driven process akin to action research, HPT practitioners are applied researchers even if they do not see themselves as such. What we need is more collaboration between scholars, practitioners, professional associations, and businesses to create a culture of engagement and involve everybody in the validation of applied research and theory development.

The purpose of this study was to determine the factors affecting cigarette use of the students at Ondokuz Mayıs University, Samsun, Turkey. The research data were collected from 384 students who answered the questionnaires. The chisquare test was used to determine the differences between smokers and non-smokers, and the t-test was used to compare group averages. Factors affecting cigarette use of students were determined by binary logistic regression analysis. The results of the research showed that male students used more cigarettes than females. Cigarette use increased after university, especially in the second and third years. The educational level and cigarette use habits of the parents affected students smoking behavior. According to the results of the model the most important factors affecting cigarette use were smoking permission situation in the student resident, smoking status of the mother, gender, and age of the student. In order to reduce cigarette use of students, besides taking legal measures, Ministry of Health, Ministry of National Education, and non-governmental organizations have to collaborate, build mutual prevention programs to raise public awareness.

Background: There is an increased risk for coronary artery disease (CAD) at modestly elevated levels of blood glucose which is still below the present threshold for type 2 diabetes mellitus (T2DM). In the present study, we aimed to define impaired glucose tolerance (IGT) and T2DM in patients with stable CAD and observe the relationship between clinical and laboratory findings. Materials and Methods: A total of 132 patients who had stable CAD and who had not been diagnosed as glucose intolerance or diabetes were enrolled. In one of the groups, there were patients with IGT or T2DM results and the other one consisted of patients with normal oral glucose tolerance test (OGTT) results. The Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was investigated in patients with fasting plasma glucose (FPG)

Objective: To investigate the importance of immunization in preventing measles infection and to determine the most useful laboratory tests for confirmation of measles. Methods: This study included pediatric cases evaluated with a presumed diagnosis of measles between December 2022 and June 2023, at Marmara University Pendik Training and Research Hospital. The effects of vaccination status and underlying disease on the clinical course, treatments, and complications were evaluated. Results: In total, 117 patients were enrolled in the study with a median age of 80 months (IQR: 32.5-125.0). Twelve patients with contact history were asymptomatic and had an underlying disorder, and intravenous immunoglobulin was given to them for postexposure prophylaxis. Fifty-one patients had confirmed measles diagnosis. Ribavirin treatment was given to three patients (a newborn, a girl with rhabdomyosarcoma, and a healthy boy) with respiratory distress. Seventy-eight percent of confirmed measles cases were unvaccinated, and all hospitalized cases were unvaccinated or undervaccinated. Four full-vaccinated children had confirmed measles infection. Measles PCR from nasopharyngeal swabs was negative in all of them, and their diagnosis was established with anti-measles IgM positivity. Conclusions: The measles vaccine is the most effective way to protect from measles and measles-related complications. Although measles can also occur in fully vaccinated patients, the disease is milder than in unvaccinated patients. Using ELISA and RT-PCR tests together may be beneficial in patients with high clinical suspicion for early diagnosis. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluates the imaging performance of two‐channel RF‐shimming for fetal MRI at 3 T using four different local specific absorption rate (SAR) management strategies. Methods: Due to the ambiguity of safe local SAR levels for fetal MRI, local SAR limits for RF shimming were determined based on either each individual's own SAR levels in standard imaging mode (CP mode) or the maximum SAR level observed across seven pregnant body models in CP mode. Local SAR was constrained either indirectly by further constraining the whole‐body SAR (wbSAR) or directly by using subject‐specific local SAR models. Each strategy was evaluated by the improvement of the transmit field efficiency (average |B1+|) and nonuniformity (|B1+| variation) inside the fetus compared with CP mode for the same wbSAR. Results: Constraining wbSAR when using RF shimming decreases B1+ efficiency inside the fetus compared with CP mode (by 12%–30% on average), making it inefficient for SAR management. Using subject‐specific models with SAR limits based on each individual's own CP mode SAR value, B1+ efficiency and nonuniformity are improved on average by 6% and 13% across seven pregnant models. In contrast, using SAR limits based on maximum CP mode SAR values across seven models, B1+ efficiency and nonuniformity are improved by 13% and 25%, compared with the best achievable improvement without SAR constraints: 15% and 26%. Conclusion: Two‐channel RF‐shimming can safely and significantly improve the transmit field inside the fetus when subject‐specific models are used with local SAR limits based on maximum CP mode SAR levels in the pregnant population. [ABSTRACT FROM AUTHOR]