• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.14 no.4
• /
• pp.435-444
• /
• 2001

Even todays, accurate and efficient algorithms for the large deformation analysis of elastoplastic frame structures lack due to the complexities of kinematics, material nonlinearities and numerical methods to cater for. The author suggests appropriate beam element based upon the incremental formulation from the 3D rod theory where Cauchy stress and engineering strain are variables to incorporate plasticity equations so that objectivity may be satisfied. A rectum mapping methods which can integrate and satisfy yield criteria efficiently is suggested and a continuation method which has global convergency and quadratic speed is developed as well. leading-unloading example problems are tested and the ideas are proved to be valuable.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.113-116
• /
• 2004

Many methods to examine the vulnerable areal for the contingencies in the power system. The most widely used index for the vulnerable area investigation has been the reactive power margin or sensitivity analysis. But we can get the results of these analyses if only the results of load flow are convergent in severe contingencies, otherwise these methods are not adoptable. We can present a good index for overcoming severe contingencies, if we can get the vulnerable areas by bus sensitivity in severe contingencies, though the power flow equation is unsolvable. This paper simulates unsolvable severe contingencies by using branch parameter continuation power flow. We can compute the vulnerable areas in unsolvable severe contingencies by normal vector at a nose point of a $\nu-V$ curve. Presented method is checked the input reactive power of the vulnerable areas in KEPCO system.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.7
• /
• pp.3533-3540
• /
• 2016

Background: Cigarette smoking is one of the leading global causes of premature and preventable death. In Brunei Darussalam, smoking-related diseases have been a primary cause of mortality for the past three decades. Despite the increasing efforts that have been made in recent years to reduce the consumption of tobacco products in Brunei, the prevalence of adolescent smoking cigarette, however has risen alarmingly, from 8.9% in 2013 to 11.4% in 2014, with a higher prevalence found in males (17.8%) than in females (4.8%). In response to the need for more effective smoking prevention programmes in Brunei, this study sought to explore factors that influence Bruneian male adolescents to start and continue smoking. Materials and Methods: A qualitative study using focus group discussions (FGDs) as the data collection method was conducted from October to November 2015. A total of 43 studentss, comprising 31 smokers and 12 non-smokers, aged 13-17 years, from two government secondary schools in Bandar Seri Begawan, participated in six FGDs. Discussions were recorded and translated. Transcripts were entered into NVivo10, before thematic analysis was conducted. Results: We identified three themes under the core construct of 'factors influencing smoking initiation' ('family as teachers', 'overt pressure from peers' and 'perceived smoking has many advantages') and three themes under the core construct of 'factors influencing smoking continuation' ('craving and addiction', 'smoking as a 'social activity' and 'easy accessibility of cigarettes'). Conclusions: Based on the findings, it is recommended that future prevention activities should be embedded in a comprehensive approach, involving all stakeholders within a community, and should be focused towards bringing a change in smoking and parenting behavior of parents, social norms within the culture towards all population levels, and at strengthening the existing non-smoking policies in schools and other public places where young people congregate.

• Journal of the Korean Data and Information Science Society
• /
• v.2
• /
• pp.1-9
• /
• 1991

Shin, Tarumi and Tanaka(1989) discussed a method of sensitivity analysis in principal component regression(PCR) based on an influence function derived by Tanaka(1988). The present paper is its continuation. In this paper we first consider two new influence measures, then apply the proposed method to various data sets and discuss some properties of sensitivity analysis in PCR.

• 한국연소학회:학술대회논문집
• /
• 2015.12a
• /
• pp.247-250
• /
• 2015

The characteristics of opposed nonpremixed tubular flames with radiation heat loss are investigated using linear stability analysis and 2-D numerical simulations. Two extinction limits, as the $Damk{\ddot{o}}hler$ number is small or large, are confirmed using finite difference method with a simple continuation method. It is verified that the results of linear stability analysis predict the number of flame cells and the critical Da starting cellular instability or amplification of temperature near both extinction limits with good resolution.

• Proceedings of the KIEE Conference
• /
• 1998.11a
• /
• pp.201-203
• /
• 1998

This paper presents the framework for analysis of small-signal stabili1ty. In this framework the equilibrium points of system DAE model are traced using continuation method and instability points are determined on the solution path. Especially Implicit shift QR-modified ARnoldi method is utilized to calculated the rightmost eigenvalues. ISPS measure is utilized to determine critical parameters.

• Journal of Theoretical and Applied Mechanics
• /
• v.2 no.1
• /
• pp.31-50
• /
• 1996

In this paper, a finite element analysis based on the local approach concept to fracture in the continuum damage mechanics is performed to analyze ductile fracture in two dimensional quasi-static state. First an isotropic damage model based on the generalized concept of effective stress is proposed for structural materials in the context of large deformation. In this model, the stiffness degradation is taken as a measure of damage and so, the fracture phenomenon can be explained as the critical deterioration of stiffness at a material point. The modified Riks' continuation technique is used to solve incremental iterative equations. Crack propagation is achieved by removing critically damaged elements. The mesh size sensitivity analysis and the simulation of the well known shearing mode failure in plane strain state are carried out to verify the present formulation. As numerical examples, an edge cracked plate and the specimen with a circular hole under plane stress are taken. Load-displacement curves and successively fractured shapes are shown. From the results, it can be concluded that the proposed model based on the local approach concept in the continuum damage mechanics may be stated as a reasonable tool to explain ductile fracture initiation and crack propagation.

• Women's Health Nursing
• /
• v.11 no.2
• /
• pp.142-147
• /
• 2005

Purpose: The objectives of this study were to investigate the current breast feeding rates in Jeju Province and to identify factors which influence breast feeding duration after birth. Method: The subjects were 189 women with a child between 12 months and 24 months old. Data was collected using a structured questionnaire from October 2003 to January 2004. Measures used in this study included general characteristics, delivery related characteristics, breast feeding related characteristics and the feeding type over a 12-month period after birth. Result: The study showed that the breast feeding rate in the first month was 63.1%, later dropping to 30.9% in the sixth month. In addition, only 14.2% of subjects were still breast feeding the baby at twelve months of age. The mean of breast feeding duration was 4.77 months. The factors which influenced breast feeding duration were wanted pregnancy, breast feeding education, planning of breast feeding and breast feeding experience. Conclusion: Considering the low rate of long-term breast feeding, the importance of breast feeding should be emphasized to promote and support the continuation of breast feeding in addition to at its initial stage. Based on the results, programs on breast feeding promotion and continuation need to be developed.

• Journal of applied mathematics & informatics
• /
• v.10 no.1_2
• /
• pp.41-50
• /
• 2002

We provide local and semilocal theorems for the convergence of Newton-like methods to a locally unique solution of an equation in a Banach space. The analytic property of the operator involved replaces the usual domain condition for Newton-like methods. In the case of the local results we show that the radius of convergence can be enlarged. A numerical example is given to justify our claim . This observation is important and finds applications in steplength selection in predictor-corrector continuation procedures.

• 정보저장시스템학회:학술대회논문집
• /
• 2005.10a
• /
• pp.177-178
• /
• 2005

The load/unload behavior of the hard disk drive slider is studied in terms of the air bearing static characteristics. The numerical continuation methods are applied to calculate suspension force - equilibrium position curve. The critical preloads of the femto size slider are analyzed. The hi-stability conditions are depicted on the skew angle - preload diagram. The perturbation method is used to check the stability of the solution branches.