• 조명전기설비학회논문지
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• 제22권2호
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• pp.94-100
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• 2008

가용송전용량(ATC)은 계통내의 한 지역에서 다른 지역까지 실제 전력을 증가시키는 것이다. 지금까지 ATC 계산은 대부분 정상상태에서 실행가능성을 주로 고려하여 계산되어 왔다. 하지만 ATC 평가시 과도안정도로 제약된 ATC 계산은 매우 중요한 부분이다. ATC 평가시에는 제약조건으로 열적용량, 전압 및 과도안정도로 제약된 상정사고(n-1)시 안전도 평가가 요구된다. 본 논문은 자코비안 행렬의 고유치를 이용하여 상정사고 우선순위를 선정하였고, 에너지 함수법을 이용하여 선로의 열적용량, 전압안정도 및 과도안정도를 고려한 ATC를 계산하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권4호
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• pp.1627-1631
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• 2015

Background: Stage at diagnosis is one of the most important prognostic factors of breast cancer survival. Because in the breast cancer case this may vary with socioeconomic characteristics, this study was performed to recognize the relationship between demographic and socioeconomic factors with stage at diagnosis in Iran. Materials and Methods: This cross-sectional, descriptive study conducted on 526 patients suffering from breast cancer and registered in Cancer Research Center of Shahid Beheshti University of Medical Sciences from 2008 to 2013. A reliable and valid questionnaire about family levels of socioeconomic status filled in by interviewing the patients via phone. For analyzing the data, Multinomial logistic regression, Kendal tau-b correlation coefficient and Contingency Coefficient tests were executed by SPSS22. Economic status, educational attainment of patient and household head and/or a combination of these were considered as parameters for socioeconomic status. First, the relationship between stage at diagnosis and demographic and socioeconomic status was assessed in univariate analysis then these relationships assessed in two different models of multinomial logistic regression. Results: The mean age of the patients was 48.3 (SD=11.4). According to the results of this study, there were significant relationships between stage at diagnosis of breast cancer with patient education (p=0.011), living place (p=0.044) and combined socioeconomic status (p=0.024). These relationships persisted in multiple multinomial logistic regressions. Other variables, however, had no significant correlation. Conclusions: Patient education, combined socioeconomic status and living place are important variables in stage at diagnosis of breast cancer in Iranian women. Interventions have to be applied with the aim of raising women's accessibility to diagnostic and medical facilities and also awareness in order to reducing delay in referring. In addition, covering breast cancer screening services by insurance is recommended.

• Journal of Yeungnam Medical Science
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• 제40권4호
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• pp.394-401
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• 2023

Background: Pregnancy is associated with a number of physical, emotional, and biological changes that can exacerbate maternal psychological disturbances, such as body image concerns and depression. Sleep disturbances during pregnancy can also have adverse impacts. This study aimed to determine the prevalence of depression, sleep disturbances, and body image concerns among pregnant women. The study also examined the relationship between these factors and pregnancy-related variables, such as bad obstetric history and whether the pregnancies were unplanned. Methods: A cross-sectional study of 146 pregnant patients was conducted at a tertiary care center over 15 months. The patients were administered the Beck Depression Inventory, Pittsburgh Sleep Quality Index, and Body Image Concern Inventory questionnaires. Contingency tables, Fisher exact test, and Spearman correlation were used to identify underlying relationships. Results: The prevalence of depression was 22.6%. Although body image disturbance was noted in only 2.7% of patients, 46.6% had poor sleep quality. Poor sleep was associated with primigravida status. Bad obstetric history and unplanned pregnancy were associated with depression. Depression was found to be significantly correlated with body image disturbances and poor sleep quality. Conclusion: Psychiatric disorders were prevalent during pregnancy. This study highlights the importance of screening for depression in pregnant patients. Counselling and caregiver education can be useful for mitigating psychological disturbances. Management of pregnancies by multidisciplinary teams that include psychiatrists could be immensely useful in improving the pregnancy experiences of patients.