• 한국산림과학회지
• /
• 제86권4호
• /
• pp.435-442
• /
• 1997

충남(忠南) 금산군(금산군), 복수면(복수면) 대성탄광(대성탄광) 폐탄광지역(폐탄광지역)에 탄광폐수(炭鑛廢水)에 의해 영향을 받는 하천수(河川水)의 오염실태(汚染實態)를 조사하였다. 하천수(河川水)의 오염정도(오염정도)를 알기 위하여 하천수(河川水)의 pH, Do, 황산(黃酸)이온, 질산(窒酸)이온, 염산(鹽酸)이온의 농도(濃度) 및 무기원소(無機元素)의 농도(濃度) 등을 측정하였다. 폐탄광(廢炭鑛)과 폐광석(廢鑛石) 더미로부터 폐수(廢水)가 유입되는 하천수(河川水)의 pH는 3.46-4.29의 범위로 산성폐수(酸性廢水)를 형성하였으며, 본 조사지역(調査地域)의 수계(水系)에서 하천수(河川水) pH의 변화는 $SO{_4}^{2-}$, Mn, Cu, Zn, Fe 및 $Mg^{2+}$ 농도(濃度)와 고도의 부(負)의 상관(相關)을 나타내었다. 폐수(廢水)가 유입된 하천수(河川水)의 황산(黃酸)이온 농도(濃度)는 236.73 - 310.50mg/l로 청정수와 비교할 때 약 10배 더 높았으며, 오염(汚染) 하천수(河川水)의 Mn과 Fe의 농도(濃度)는 각각 0.56 - 0.83mg/l, 5.89 - 10.58mg/l로 Mn 농도(濃度)는 청정수와 비교할 때 약 20배나 높았다. 오염(汚染) 하천수(河川水)의 $Mg^{2+}$와 $Ca^{2+}$ 농도(濃度)는 청정지역(淸淨地域)과 비교해서 높게 나타났다. 산성광산폐수(酸性鑛山廢水)의 오염지표(汚染指標)(AMDI)는 오염계류(汚染溪流)에서 42-51이었고, 비오염계류(非汚染溪流)에서는 70 - 76으로 오염계류(汚染溪流)에서 낮았다.

• Structural Engineering and Mechanics
• /
• 제88권3호
• /
• pp.239-249
• /
• 2023

The Radial Point Interpolation Method (RPIM) has been proposed to overcome the difficulties associated with the use of the Radial Basis Functions (RBFs). The RPIM has the following properties: Simple implementation in terms of boundary conditions as in the Finite Element Method (FEM). A less expensive CPU time compared to other collocation meshless methods such as the Moving Least Square (MLS) collocation method. In this work, we propose an adaptive high-order numerical algorithm based on RPIM to simulate the thermoviscoplastic behavior of a material mixing observed in the Friction Stir Welding (FSW) process. The proposed adaptive meshfree RPIM algorithm adapts well to the geometric and physical data by choosing a good shape parameter with a good precision. Our numerical approach combines the RPIM and the Asymptotic Numerical Method (ANM). A numerical procedure is also proposed in this work to automatically determine an improved shape parameter for the RBFs. The efficiency of the proposed algorithm is analyzed in comparison with an iterative algorithm.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권9호
• /
• pp.4031-4035
• /
• 2015

Background: Breast cancer is one of the most feared diseases among women and it could induce the development of psychological disorders like anxiety and depression. An assessment was here performed of the status and to determine contributory factors. Materials and Methods: A cross-sectional study was conducted among breast cancer patients at University Kebangsaan Malaysia Medical Center (UKMMC), Kuala Lumpur. A total of 205 patients who were diagnosed between 2007 until 2010 were interviewed using the questionnaires of Hospital Anxiety and Depression (HADS). The associated factors investigated concerned socio-demographics, socio economic background and the cancer status. Descriptive analysis, chi-squared tests and logistic regression were used for the statistical test analysis. Results: The prevalence of anxiety was 31.7% (n=65) and of depression was 22.0% (n=45) among the breast cancer patients. Age group (p= 0.032), monthly income (p=0.015) and number of visits per month (p=0.007) were significantly associated with anxiety. For depression, marital status (p=0.012), accompanying person (p=0.041), financial support (p-0.007) and felt burden (p=0.038) were significantly associated. In binary logistic regression, those in the younger age group were low monthly income were 2 times more likely to be associated with anxiety. Having less financial support and being single were 3 and 4 times more likely to be associated with depression. Conclusions: In management of breast cancer patients, more care or support should be given to the young and low socio economic status as they are at high risk of anxiety and depression.