DEVELOPMENT OF AN IMPROVED THREE-DIMENSIONAL STATIC AND DYNAMIC STRUCTURAL ANALYSIS BASED ON FETI-LOCAL METHOD WITH PENALTY TERM

SEIL KIM,HYUNSHIG JOO,HAESEONG CHO,SANGJOON SHIN 한국산업응용수학회 2017 Journal of the Korean Society for Industrial and A Vol.21 No.3

In this paper, development of the three-dimensional structural analysis is performed by applying FETI-local method. In the FETI-local method, the penalty term is added as a preconditioner. The OPT-DKT shell element is used in the present structural analysis. Newmark- method is employed to conduct the dynamic analysis. The three-dimensional FETI-local static structural analysis is conducted. The contour and the displacement of the results are compared following the different number of sub-domains. The computational time and memory usage are compared with respect to the number of CPUs used. The three-dimensional dynamic structural analysis is conducted while applying FETI-local method. The present results show appropriate scalability in terms of the computational time and memory usage. It is expected to improve the computational efficiency by combining the advantages of the original FETI method, i.e., FETI-mixed using the mixed local-global Lagrange multiplier.

Tasks for the Catholic Church in Korea on the Path of Pope Francis

Seil Oh(오세일) 신학과사상학회 2018 가톨릭 신학과 사상 Vol.- No.81

1. Finding the Signs of the Times in Korea in the Midst of Change and Conflict 2. The Cultural Crisis of the Korean Catholic Church 3. Integrated Messages of Pope Francis 4. Tasks for the Catholic Church in Korea 5. Special Conundrums for the Catholic Church in Korea 교종 프란치스코는 즉위 직후부터 전 세계인들에게서 새롭고 진정성 있는 종교 지도자로 인식되었다. 특히 2014년 8월 한국 방문 시에도 성령의 새로운 바람을 실감할 수 있을 정도로 깊은 영감과 인상을 남겼다. 교종 프란치스코는 “제2차 바티칸 공의회정신” 아래 양성을 받았고 남미의 정치사회적 억압 속에서 ‘복음’과 ‘영신수련’에 근거한 “진정성 있는 리더십(권위)”을 실천하며 아울러 “삶의 주변부”로 나아가 교회가 예언직을 수행하고 “야전병원”의 역할을 할 것을 강조해 왔다. 그중에서도 특히 제도 교회의 영역을 넘어 보편 인류를 지향하는 “하느님의 백성”과 함께 정진하는 “공동합의성”(synodality)을 사목에서 가장 중요하게 생각해 왔다. 그 정신을 성령께서 활동하시는 시대의 표징으로 해석하자면, 교회의 지도자에게는 하느님 자비와 사랑을 체험하고 하느님 백성을 돌보고 위로하는 영적 책임과 의무에 충실해야 하는 “사목적 책무성”이 있음으로 집약된다. 한국천주교회는 보유론의 특성에서 시작하였지만 전통 유교사회에서 “천주 앞에서 만인이 평등하고 존귀하다”는 복음의 기쁨을 혁명적으로 증거하여 왔다. 하지만 오늘날 천주교회에서는 유교 문화의 외피에서 벗어나지 못하고 신분(성직주의), 위계(관료제), 내재적 의식(닫힌 공동체) 등의 폐쇄적 관행, 그리고 주지주의식 교육에 대한 강조로 인해 “앎과 삶의 분리 문제”가 크게 부각되고 있다. 교종 프란치스코의 삶에 근거한 가르침을 한국 문화 안에서 수용하고자 할 때, “진정성 있는 내적 권위”의 리더십을 회복하고, “사목적 책무성”에 기반하여 영적, 제도적 책무성을 강화할 필요가 있으며, 교회 기관들, 특히 본당은 사목의 최전선으로서 울타리를 넘어 지역 사회의 가난한 이들에게 열린 소통과 봉사를 수행하도록 초대받는다. 특히, 한국천주교회는 두 가지 화두를 대면하고 있다. 세속적계층과 서열, 성공에 관해서 집합적 강박의식이 강한 한국인의 의식구조를 지배하는 전통 유교 문화에서 복음의 기쁨을 찾고 실현해 낼 수 있도록 문화의 복음화가 매우 절실하다. 또한 남북분단을 치유하고 화해하며 일치와 평화의 길로 나아가고자 하는 모든 기도와 노력에 있어 한국천주교회가 기여할 수 있는 를 고민해야 한다.

The Crisis of Korean Catholic Church in the Post-Secular Society

Seil Oh(오세일) 신학과사상학회 2015 가톨릭 신학과 사상 Vol.- No.76

Load-Balancing Proxy Mobile IPv6 Networks with Mobility Session Redirection

Seil Jeon,Aguiar, Rui L.,Namhi Kang IEEE 2013 IEEE COMMUNICATIONS LETTERS Vol.17 No.4

<P>This letter presents a mobility session redirection scheme for Proxy Mobile IPv6 networks (PMIPv6-MSR), facilitating LMA changes in the middle of a mobility session for, e.g. load-balancing purpose. Analytical results confirm that the proposed PMIPv6-MSR shows lower blocking and dropping probability than PMIPv6 without load control (PMIPv6-NLC), as offered load increases.</P>

Simultaneous Task Assignment and Path Planning Using Mixed-Integer Linear Programming and Potential Field Method

Seil An,H. Jin Kim 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

This paper investigates a task assignment and path planning problem in a situation where threats exist. Common task assignment algorithms obtain straight line paths during the task assignment phase and then plan the paths considering the threats, which can decrease performance of task assignment and task success rate. Therefore, task assignment with real-time path planning is presented in this paper using Mixed-Integer Linear Programming(MILP) and potential field method. Real-time path planning usually requires amount of computational time but MILP simplifies the task assignment problem so real-time path planning can be applied to task assignment. Task selection algorithm is also presented to compensate the modified sub-optimal MILP. MILP task selection algorithm is compared with a brute-force search algorithm which obtains optimal solutions in situations without threats. Simulation results are presented to show the advantages of MILP task selection algorithm in avoiding threats and performing tasks successfully.

Outside Directors’ Insider Trading Around Board Meetings

( Seil Kim ),( Seungjoon Oh ) 한국금융연구원 2022 금융연구 working paper Vol.2022 No.15

Using a novel dataset containing U.S. companies’ regular board meeting schedules, we find evidence of informed trading by outside directors prior to board meetings. In the days prior to board meetings, when outside directors possess private information, they make purchases that yield higher abnormal returns and are larger than those made during periods distant from board meetings. We find no such pattern for inside directors who possess private information regardless of the timing of board meetings. Moreover, we find that these patterns are especially exhibited by trades made by more sophisticated directors, trades made prior to board meetings that result in news disclosures, and nonroutine trades. Our results suggest that outside directors trade based on information they obtain in preparation for board meetings.

WiMAX multicast/broadcast services support in home environments

Seil Jeon,Younghan Kim IEEE 2010 IEEE transactions on consumer electronics Vol.56 No.3

<P>Multicast/broadcast service (MCBCS) is one of the most advanced services of all wireless network standards. Recently, the WiMAX forum introduced MCBCS with three different types of internal data paths that differentiate the ways in which MCBCS data are packaged and delivered. In order to extend WiMAX access to the indoor users in home environment, femtocell technology has been considered. However, an application and evaluation of MCBCS structures over the WiMAX femtocell system have not been studied yet. In this paper, we therefore classify the applicable MCBCS network model for home users in femtocell systems and evaluate the performance of each model in terms of transmission overhead and buffer size required in data packaging. From the results, we note that the separated femto model using type-3 and type-4 data paths has more transmission overhead and requires more buffers than type-1, but these are reduced when the error rate decreases between the femto gateway (Fe-GW) and the WiMAX femto access point (WFAP). Moreover, we confirm that there are no differences in performance among types of model in the combined femto model.</P>

Simple Maneuver for Estimating the Depth of the Focal Activation Source in Myocardium

Seil Oh 대한심장학회 2020 Korean Circulation Journal Vol.50 No.5

Background and Objectives: It is difficult to estimate the depth of the focal source by activation mapping. The present study was performed to demonstrate the usefulness of a simple maneuver in estimating the depth of the focal activation source (S). Methods: A total of 44 sites (15 shallow, depth<3.5 mm; 29 deep, depth>5.5 mm) were analyzed in 3 canine left ventricles under general anesthesia. A custom-made bipolar needle electrode was used to simulate a focal activation source. A mapping catheter with an electrode tip size of 2 mm, band electrode size of 1 mm, and inter-electrode spacing of 2-10-2 mm was placed at the mapping area. The position of the center of the distal 2 electrodes was kept at the insertion site of the needle electrode. The time interval between distal and proximal electrodes of the mapping catheter (Ttachy) was measured during needle electrode pacing. The time interval between distal and proximal electrodes (Tpace) was measured during pacing with distal electrodes of a mapping catheter. Depth index (δ) was defined as Ttachy/Tpace. Using in vivo data, simulation was performed to evaluate the depth and δ. Results: Ttachy was 24±7.7 ms and 15±5.6 ms for shallow source and deep source simulation, respectively (p<0.001). δ values were 0.86±0.21 and 0.55±0.21 for shallow source and deep source simulation, respectively (p<0.001). According to simulation data, if δ<0.52, the depth of the focal source will be >5.5 mm. Conclusions: Ttachy was shorter and δ was smaller for a deep S than for a shallow S.

Experimental Evaluation of Network-based Handover Management with Proxy Mobile IPv6

Seil Jeon,Jae Yeon Choi,Younghan Kim 대한전자공학회 2008 ICEIC:International Conference on Electronics, Inf Vol.1 No.1

The PMIPv6 (Proxy Mobile IPv6) provides the network-based mobility management function without reconfiguring the IP address of a Mobile Node (MN) moving in the same Proxy Mobile IP domain. In this paper, we design and implement a PMIPv6 test-bed and experiment and compare the performance of the PMIPv6 with that of the MIPv6 (Mobile IP6), and show the improved disruption time between continuous packets and the packet loss rate of the PMIPv6.

Learning Parameters from Manual Task Assignments for Mobile Robots

Seil An,Dong Jun Kwak,H. Jin Kim 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10

For case where exist some threats in field of task assignment, threat avoidance is needed to be considered. Then both fast arrival and threat avoidance are used to form the performance measure. The policies of task assignment decide which factor is mostly considered between arrival time and threat avoidance. The purpose of this research is estimating the hidden policy from user’s manual task assignment. Using Naive-Bayes classification, we achieved satisfactory policy estimation for task assignment from testing several users.