• Journal of the Korea Concrete Institute
• /
• v.22 no.2
• /
• pp.171-177
• /
• 2010

Recently, Performance Based Design (PBD) method has been studied as a next generation structural design method, which enables a designed structure to satisfy the required performance during its service life. One method of deciding whether the required performance has been satisfied is Bayesian method, which has been commonly used in seismic analysis. Generally, it is presented as a conditional probability of exceeding some limit state (i.e., collapse) for a given ground motion. In PBD of concrete mixture design, the same methodology can be applied to assess concrete material performance based on some conditional parameters (i.e. strength, workability, carbonation, etc). In this paper, a detailed explanation of the procedure of drawing satisfaction curve by using Bayesian method based on various material parameters is shown. Also, a discussion of using the developed satisfaction curves for PBD for concrete mixture design is presented.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.05a
• /
• pp.138-144
• /
• 2004

Pneumatic damping through a orifice type duct for OWC type wave energy device is studied experimentally. Forced oscillation tests are made to measure chamber pressure and velocity of air flaw through orifice. Pneumatic damping coefficient are deducted from the experimental research, and discussion are made far the influence of frequency, heave amplitude, and orifice size. Finally two formula are proposed for the estimation of non-dimensional pneumatic damping coefficient by regression analysis. The proposed formula proves to be a reliable method far practical application.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.27-37
• /
• 2011

Currently, in the course of introducing rolling stocks, RAMS standard and management by system engineering method apply to rolling stock system. Technical elements and results applied in system introduction phase are just used in acquisition stage, and these are not applied to the standard in railway site. Therefore, it is difficult to apply to standardized technology and quality assurance measure. Due to the establishment of the EU, railway operation system is internationalized and the international railway standards are being discussed in various ways. In addition, standardization is expanded from manufacture to operation and maintenance. It is to provide consistent standard in quality, cost calculation of maintenance technology, maintenance technology and quality assurance in case of international railway safety incidents. Therefore, this study is to find technology, quality and cost management model to be used for choosing railway-operation guidance by considering how technologies & quality have changed in system life cycle, compared with estimated standards, based on the technologies & quality-related result in the process of getting new rolling stocks and management guidance for operation & maintenance process.

• Journal of the Korea Safety Management & Science
• /
• v.15 no.3
• /
• pp.113-125
• /
• 2013

According to 2012 OECD environmental report, Korea was ranked as the first country of water stress. Water footprint is a method to calculate water usage during the life cycle of a product from material procurement through production to disposal to recycle and to quantify the load to water resources. In water footprint calculation, water consumption unit is used. Agricultural water use is over 48% so it is urgent to mange that area Korea needs to spread the discussion about water footprint as quickly as possible, for the study to prevent social and environmental problems due to water shortage. This paper, through water footprint calculation and comparison in Chungju and Geochang areas, looks to counter measures for water risk, targeting domestically-produced apple.

• Earthquakes and Structures
• /
• v.5 no.6
• /
• pp.625-655
• /
• 2013

This paper investigated the seismic behaviour of an innovated non-ductile precast concrete wall structural system; namely HC Precast System (HCPS). The system comprises load-bearing precast wall panels merely connected only to column at both ends. Such study is needed because there is limited research information available in design codes for such structure particularly in regions having low to moderate seismicity threats. Experimentally calibrated numerical model of the wall system was used to carry out nonlinear pushover analyses with various types of lateral loading patterns. Effects of laterally applied single point load (SPL), uniformly distributed load (UDL), modal distributed load (MDL) and triangular distributed load (TDL) onto global behaviour of HCPS were identified. Discussion was focused on structural performance such as ductility, deformability, and effective stiffness of the wall system. Thus, a new method for engineers to estimate the nonlinear deformation of HCPS through linear analysis was proposed.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.26 no.9
• /
• pp.1311-1318
• /
• 2002

An experimental model is investigated in this paper using the experimental method with a shock tube and the numerical technique. The shock-vortex interaction generated by this model is visualized with various methods: holographic interferometry, shodowgraphy, and numerical computation. In terms of shock dynamics, there are two meaningful physics in the present problem. They are reflective wave from the slip layer at the vortex edge and transmitted shock penetrating the vortex core. The discussion in this study is mainly focused on the two kinds of waves contributing to the quadrupolar pressure distribution around the vortex center during the interaction.

• Journal of the Ergonomics Society of Korea
• /
• v.35 no.4
• /
• pp.247-261
• /
• 2016

Objective:The aim of this paper is to discuss the nuclear safety culture in Korea. Background: Recently, Korean nuclear field has met a strong anti-nuclear trend after a few happenings, as well as Fukushima accident, which are turned out to be caused by organizational pitfalls and safety culture defects in general. Method: We review the concepts and constructs of safety culture based on the brief history of the nuclear safety culture that IAEA mainly raised after the Chernobyl accident in 1986. Additionally, we give a comparative discussion on the approach to the safety culture with U.S. Results: Finally, we discuss the three technical domains and propose six selected domestic issues related to the nuclear safety culture for coping with the demanding requests on nuclear safety in Korea. Conclusion and Application: We suggest several recommendations and a research direction in the form of a re-start line for the nuclear safety culture in Korea.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.2352-2355
• /
• 2003

In recent yeas, studies on computer aided diagnosis (CAD) using image analysis on CT images have been conducted with respect to various diseases. Extracting ground-glass opacities (GGO) on lung CT images is one of such subjects, though it has not found an established method yet. If the region of ground-glass opacities is large on CT images, it can be detected without much difficulty. On the other hand, if the region is small, it is still difficult to find it exactly. In the latter case, increasing overlooking possibility cannot be avoided according to smaller size of the region. To solve this difficulty, this paper proposes an automatic technique for extracting ground-glass opacities on lung CT images employing some statistical parameters of a gray level histogram and a differential histogram. The proposed technique is applied to some lung CT images in the performed experiment. The results are shown with discussion on future work.

• Journal of Haehwa Medicine
• /
• v.21 no.1
• /
• pp.143-150
• /
• 2012

Objectives : This study was aimed to review the trend of tongue diagnosis studies in Korean Medicine on various aspect and to suggest better studies. Method : We collected papers on tongue diagnosis studies in the internet site 'nanet, riss, dbpia, society' using the keyword 'tongue diagnosis' between 2002 and 2012. Then we analyzed them. Results : There were 33 study papers that related in tongue diagnosis between 2002 and 2012. Conclusions : To make a reproducibility and a objectivity of tongue diagnosis, it needs to have a unification of the system. So it is is necessary that having a discussion about the standard of tongue diagnosis.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.11a
• /
• pp.202-203
• /
• 2015

In light of the recent media outlets revealing structural waterleakage problems, construction workers, design planners and related enterprises are investing more effort towards forming a solution plan for these issues. This study proposes the structuralization of a information network system that allows the selection and discussion of optimal measures for waterproofing related techniques and expert informations online in a realtime setting.