• Structural Engineering and Mechanics
• /
• v.16 no.2
• /
• pp.219-240
• /
• 2003

One of the most versatile approaches for analyzing the dynamic behavior of structural systems is direct time integration of semi-discrete equations of motion. However responses computed by time integration are generally inexact and hence the corresponding errors would rather be studied in advance. In spite of the various error estimation formulations that exist in the literature, it is accepted practice to repeat the analyses with smaller time steps, followed by a comparison between the results. In this paper, after a review of this simple method and disregarding the round-off errors, a more efficient, reliable and yet simple method for estimating errors and enhancing the accuracy is proposed. The main objectives of this research are more realistic error estimation based on the concept of convergence, approximately controlling the reliability by comparing the actual rate of convergence with the integration method's order of accuracy, and enhancement of reliability by applying Richardson's extrapolation. Starting from the errors at specific time instants, the study is then generalized to cases in which the errors should be estimated and decreased at specific events e.g. peak responses. Numerical study illustrates the efficacy of the proposed method.

• Journal of the Korean Society of Industry Convergence
• /
• v.12 no.3
• /
• pp.149-155
• /
• 2009

A new finite element equation is derived by applying quadratic and cubic time integration scheme to the variational formulation in time-integral for the analysis of the transient elastodynamic problems to increase the numerical accuracy and stability. Emphasis is focused on methodology for cubic time integration scheme procedure which are never presented before. In this semidiscrete approximations of the field variables, the time axis is divided equally and quadratic and cubic time variation is assumed in those intervals, and space is approximated by the usual finite element discretization technique. It is found that unconditionally stable numerical results are obtained in case of the cubic time variation. Some numerical examples are given to show the versatility of the presented formulation.

• Convergence Security Journal
• /
• v.15 no.7
• /
• pp.125-134
• /
• 2015

This study aims to investigate what to be prepared and implemented for the military integration when South and North Korea are making progress toward unification. Although we can not exactly predict when the unification will be completed at this time, preparations for the military integration should be ready ahead of time. Since the failure of the military integration can threat the unification, elaborated and practical solutions are required. Therefore, the study tries to answer the following questions : 1) What types of the military integration are desirable and what are the prerequisites for the unification of Korean Peninsular? ; 2) What potential military tasks could be caused by military integration? ; 3) What are the core and major tasks among them and how could they be solved in practical aspects?

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1998.04a
• /
• pp.407-412
• /
• 1998

In this work, a new time integration method is proposed using the generalized derivative concept to simulate the dynamic phenomena having sudden constraint occurring in dynamic contact/impact problems. By the adoption of the generalized derivative concept and jump assumption, discontinuity can be incorporated in time integration and as a result, the algorithm does not need any other special consideration of jumps in dynamic field variables due to sudden constraint like dynamic contact-release conditions. To observe the characteristics of the proposed time integration method, the stability and convergence analyses are carried out. In numerical tests, several dynamic contact/impact problems are analyzed by straightforward application of the proposed time integration method with the exterior penalty method.

• The Korean Journal of Food & Health Convergence
• /
• v.7 no.6
• /
• pp.9-16
• /
• 2021

There are two forms of medicine that have existed over time and are important in the delivery of expert health care. The forms of medicine are traditional and modern medicine. This study was aimed at assessing the awareness and perspective on the use and integration of traditional and modern medicine in a rural area of Sokoto State, Nigeria. Two hundred and seventy-one (271) respondents were recruited and a self-administered questionnaire on the awareness and perspective on use and integration of traditional and modern medicine was used to assess the participant's view. Among the participants, 200(73.8%) were females. The mean±SD age of respondents was 30.55±9.73 years. 80.8% of the respondents were aware of traditional medicine while 100% were aware of modern medicine. All respondents prefer modern medicine but about 28.8% support integration of both healthcare services. The results were considered significant when p-value was less than 0.005. There is a statistically significant relationship between the integration of traditional and modern forms of medicine and age, gender, religion, education, ethnicity and occupation but not for marital status. Though all the respondents preferred modern medicine to traditional medicine, some people still feel it will be good to combine both for a better healthcare system.

• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.12
• /
• pp.53-63
• /
• 1995

In the analysis of metal forming problems, the explicit time integration finite element method, which does not have convergence problems, is frequently used. The present work is to assess the applicability of the explicit time integration finite element method to quasi-static metal forming problems. Compressing analyses of thin-walled tubes and solid cylinders are performed with different loading velocities. The computed buckled profiles of thin walled tubes are compared with the theoretical and experimental ones and it is found that at sufficiently low loading velocity, the explicit time integration finite element method accurately predict quasi-static buckled profiles. When loading volocity is increased, the computed buckled profiles of thin-walled tubes are very sensitive to loading velocity however the computed profiles of solid cylinders are less sensitive to loading velocity. In orther words, the geometrically self-constrained specimens like solid cylinders are less sensitive to loading velocity than the geometrically unconstrained specimens like thin-walled tubes. As a result, it is found that the geometrically self-constrained problems which include the greater part of metal forming problems can be efficiently analyzed with loading velocity control technique.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.8 no.6
• /
• pp.141-146
• /
• 2008

Recently, it is studying to provide to users through internet in the SensorWeb of OGC(Open Geospatial Consortium) saving and maintaining data and image information gathered from sensor network. It is necessary to study about data convergence as binding audio and video for delivering the sensing data and image information to users with real-time system. In this article, it suggests how to convergence sensing data and moving picture collected from the sensor network using index. This program indicates both of them that collected sensing data and information identified of moving picture in the integration index and based on this program provides sensing data moving picture at the same time referencing integration index, if the user asks. To verify suggested method designing real-time multimedia service structure using sensor network and image installation and implementing Ubiquitous realtime multimedia system integrating moving picture and sensing data based on index. As a result of this program, it is confirmed providing real-time multimedia service to request information of application service using integration index collected image and sensing data from wireless sensor network and image installation suggested data convergence method.

• Journal of Digital Convergence
• /
• v.16 no.5
• /
• pp.289-297
• /
• 2018

The purpose of this study was to recognition of organ donation of nursing students in convergence and integration time so was to investigate the relationship between consciousness of biomedical ethics and attitude in organ donation. The participant were 202 nursing students and data were collected from April until July of 2017. Findings showed that consciousness of biomedical ethics wes 2.98 and attitude in organ donation was 2.67, and brain death was lowest at 2.67. The relationship between two variables showed a positive correlation(r=.18, p<.01), and Affecting Factors of consciousness of biomedical ethics was attitude in organ donation, gender, experience of studying for biomedical ethics, and the explanatory power was 9.1%. This result that for promotion of recognition of organ donation, we propose to implementing nursing ethics education focused on brain death and attitude in organ donation.

• Journal of the Korea Convergence Society
• /
• v.9 no.10
• /
• pp.249-255
• /
• 2018

This paper presents a human-centered control algorithm for personalized autonomous driving based on the integration of inverse time-to-collision and time headway. In order to minimize the sense of difference between driver and autonomous driving, the human-centered control technology is required. Driving characteristics in case that vehicle drives with the preceding vehicle have been analyzed and reflected to the longitudinal control algorithm. The driving characteristics such as acceleration, inverse time-to-collision, time headway have been analyzed for longitudinal control. The control algorithm proposed in this study has been constructed on Matlab/Simulink environment and the performance evaluation has been conducted by using actual driving data.

• Journal of the Korean Society for Precision Engineering
• /
• v.32 no.1
• /
• pp.17-24
• /
• 2015

Smart factory requires 4 Zero factors including Zero Waiting-time, Zero Inventory, Zero Defect, Zero Down-time) that needs IT convergence for production resources of 4M1E(Man, Machine, Material, Method, Energy) in real time and event processing in all type of manufacturing enterprises. This paper will be explaining about core emerging production IT convergence technologies including cyber device security, 4M1E integration, real time event driven architecture, common platform of manufacturing standard applications, smart factory to-be model for small and medium manufacturing enterprises.