• 한국산업융합학회 논문집
• /
• 제4권2호
• /
• pp.167-175
• /
• 2001

In this study, a general perturbation method is presented to reanalysis dynamic response of base-isolated systems. The perturbation is expanded to general order and which provide the formulation of perturbed solutions. in which eigensolutions of non-modified system are treated as unperturbed solutions. The accuracy of present method is tested using a 2-DOF system with isolator, where the stiffness and damping coefficients of isolator are changed, respectively, The reanalyzed eigensolutions and response using perturbed solutions are successfully approached to exact ones after just first perturbation. Supposing the practical criterion as ${\pm}5%$ error, the modification range of -50%~30% from original system can be allowed for the first order perturbation. Using higher order solutions, the applicable range will be wide.

• Journal of applied mathematics & informatics
• /
• 제28권3_4호
• /
• pp.823-835
• /
• 2010

In this paper, A FSQP algorithm for degenerate inequality constraints optimization problems is proposed. At each iteration of the proposed algorithm, a feasible direction of descent is obtained by solving a quadratic programming subproblem. To overcome the Maratos effect, a higher-order correction direction is obtained by solving another quadratic programming subproblem. The algorithm is proved to be globally convergent and superlinearly convergent under some mild conditions. Finally, some preliminary numerical results are reported.

• Journal of applied mathematics & informatics
• /
• 제9권1호
• /
• pp.311-320
• /
• 2002

For second order linear elliptic problems over smooth domains, it is well known that the rate of convergence of the error in the $L_2$norm is one order higher than that in the $H^1$norm. For polygonal domains with reentrant corners, it has been shown in [15] that this extra order cannot be fully recovered when the h-version is used. We present theoretical and computational examples showing the sharpness of our results.

• Structural Engineering and Mechanics
• /
• 제10권5호
• /
• pp.427-440
• /
• 2000

The formulas for the perturbation analysis with modes of close eigenvalues are derived in this paper. Emphasis is made on the consistency of the straightforward perturbation process, given the complete terms of perturbations in the zeroth-order, which is a form of Rayleigh quotient, and in the higher-orders. By dividing the perturbation of eigenvector into two parts, the first-order perturbation with respect to the modes of close eigenvalues is moved into the zeroth-order perturbation. The normality condition is employed to compute the higher-order perturbations of eigenvector. The algorithm can be condensed to a single mode with a distinct eigenvalue, and this can accelerate the convergence of the perturbation analysis. The example confirms that the perturbation approximation obtained from the suggested procedure is in a good accuracy on the eigenvalues, eigenvectors, and normality.

• Structural Engineering and Mechanics
• /
• 제58권6호
• /
• pp.949-966
• /
• 2016

The second order analysis taking place due to non-linear behavior of the structures under the mechanical and geometric factors through implementing exact and approximate methods is an indispensible issue in the analysis of such structures. Among the exact methods is the slope-deflection method that due to its simplicity and efficiency of its relationships has always been in consideration. By solving the differential equations of the modified slope-deflection method in which the effect of axial compressive force is considered, the stiffness matrix including trigonometric entries would be obtained. The complexity of computations with trigonometric functions causes replacement with their Maclaurin expansion. In most cases only the first two terms of this expansion are used but to obtain more accurate results, more elements are needed. In this paper, the effect of utilizing higher order terms of Maclaurin expansion on reducing the number of required elements and attaining more rapid convergence with less error is investigated for the Bernoulli beam with various boundary conditions. The results indicate that when using only one element along the beam length, utilizing higher order terms in Maclaurin expansion would reduce the relative error in determining the critical buckling load and kinematic parameters in the second order analysis.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2019년도 춘계학술대회
• /
• pp.372-374
• /
• 2019

제 4차 산업 혁명을 맞이하고 있는 최근 대학 교육은 전문적인 지식의 전수보다 문제해결력이나 창의성을 강조하고 있다. 뿐 만 아니라 첨단 정보통신기술이 융합되어 혁신적인 변화가 이루어지면서 융합 교육에 대한 필요성이 더욱 증대되고 있다. 이에 본 논문에서는 IT 융합 교육을 실시한 후와 일반 융합 교육을 실시한 후, 창의적 문제 해결 역량의 차이를 비교 분석하였다. 연구 결과 일반 융합 교육보다 IT 융합 교육을 받은 수강생의 창의적 문제 해결 역량이 더 높았으며 통계적으로도 유의미한 차이를 나타냈다. 이에 창의적 문제 해결 역량 함양을 위해 대학에서는 각종 강좌에 IT 융합 교육을 연계한 교육이 활성화되어야 할 것이다.

• Structural Engineering and Mechanics
• /
• 제73권1호
• /
• pp.1-16
• /
• 2020

Finite elements based on the partition of unity (PU) approximation have powerful capabilities for p-adaptivity and solutions with high smoothness without remeshing of the domain. Recently, the PU approximation was successfully applied to the three-node shell finite element, properly eliminating transverse shear locking and showing excellent convergence properties and solution accuracy. However, the enrichment with the PU approximation results in a significant increase in the number of degrees of freedom; therefore, it requires greater computational cost, thus making it less suitable for practical engineering. To circumvent this disadvantage, we propose a new strategy to decrease the total number of degrees of freedom in the existing PU-based shell element, without loss of optimal convergence and accuracy. To alleviate the locking phenomenon, we use the method of mixed interpolation of tensorial components and perform convergence studies to show the accuracy and capability of the proposed shell element. The excellent performances of the new shell elements are illustrated in three benchmark problems.

• 한국병원경영학회지
• /
• 제29권1호
• /
• pp.64-75
• /
• 2024

Purposes: This study aims to identify the characteristics of the study subjects by age, including non-elderly people aged 19 to 65, pre-elderly people aged 65 to 75, and elderly people aged 75 and over, and to identify factors affecting health literacy based on an investigation of the health literacy level of each study group. This study would like to find out the differences in health literacy factors by age group. Methodology: The HLS-EU-Q16, developed by the World Health Organization Regional Office for Europe for the Health literacy Survey of Europeans, will be applied in this study. Findings: We found that scores decreased in order of nonelderly, pre-elderly, and late-elderly in health care, disease prevention, and health promotion. In addition, health literacy was lower in the older age group, and higher health literacy was associated with being unmarried, higher education, and higher income. In terms of influencing factors, marital status was significantly different in the non-elderly group, and higher education level was associated with higher health literacy. Practical Implications: The results of this study show that health literacy levels are low in all age groups, and efforts to improve health literacy in younger, older, and non-elderly groups are needed. It is expected that age-specific health literacy strategies can help improve the level of understanding and utilization of health information, improve health, and lead a healthy life.

• 디지털융복합연구
• /
• 제19권4호
• /
• pp.185-192
• /
• 2021

본 연구의 목적은 병원행정직의 감성지능과 융복합 요인들의 관련성을 조사하는데 있다. 2019년 5월 1일부터 5월 31일까지의 조사기간에 J지역에서 임의로 선정된 19개 병원의 행정직원 212명의 무기명 자기기입식 응답이 분석 자료로 사용되었다. 위계적 다중회귀분석 결과, 자아탄력성이 높을수록, 조직충성도가 높을수록, 조직헌신이 높을수록 감성지능이 높았으며, 이들의 설명력은 43.0%이었다. 이러한 분석결과를 볼 때, 병원행정직의 감성지능을 높이기 위해서는 자아탄력성을 높이고, 조직충성도를 증가시키고, 조직헌신을 상승시키는 노력이 필요하다. 이상의 결과는 병원행정직의 감성지능을 높이기 위한 병원의 산업보건교육 및 직무관리에 향후 응용이 기대된다. 추후연구에서는 병원행정직의 감성지능에 영향을 미치는 구조방정식 모형의 수립 및 분석이 필요하다.

• 디지털융복합연구
• /
• 제18권10호
• /
• pp.527-535
• /
• 2020

연구 목적은 충청권 초등학생 자녀를 둔 어머니를 대상으로 가공식품 표시기준 인식이 구매행동에 미치는 융복합 효과를 살펴보기 위한 것으로, 가공식품 구매행동에 따른 집단 구분을 위해 2단계 군집분석을 하였고, Schwarz's BIC 기준에 의해 군집수를 결정하였다. 그룹 간 구매행태 특징 분석 결과 '편의추구형'과 '대형마트선호형', '고비용반복 구매형'의 3개 모형이 결정되었다. 그룹별 학력 및 직업은 '대형마트선호형'의 대졸 이상 비율이 유의적으로 높았고, '고비용반복구매형'의 취업모 비율이 높았으며, 식품표시기준 필요성은 '대형마트선호형'이 다른 그룹보다 높았다. 모든 그룹에서 식품표시기준 항목 중 '유통기한'을 가장 중요한 것으로 인식하였고, 구매 시 고려사항은 '사용원료'와 '식품첨가물', '영양성분표시'에서 '대형마트선호형'이 높은 점수를 보였다. 가공식품 구매행동 개선을 위해서는 무엇보다 실생활에 쉽게 적용할 수 있는 대상자 맞춤형 교육매체 개발이 필요하다.