• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2001.05a
• /
• pp.133-138
• /
• 2001

Formal safety assessment (FSA) is defined as a structured and systematic methodology aimed at enhancing maritime safety including protection of life, health, and the marine environment and property, by using risk and cost/benefit assessment or, more specifically, it is a process of identifying hazard, evaluating risk and deciding on course of action to control those risks. Emphasis is placed on the structural aspect of the failure of cargo hold. This study is expected to illustrate how a new methodology, i.e. the Formal Safety Assessment, can be applied to specific ship safety problems.

• Journal of the Korea Concrete Institute
• /
• v.11 no.3
• /
• pp.81-88
• /
• 1999

In order to properly evaluate the shear strength of reinforced concrete circular columns due to the transverse shear reinforcement, the average of fractions of forces generated along the circular transverse hoops across the shear failure plane in the loading direction is calculated. For this, the center-to-center diameter of circular transverse hoops. spacing and the crack angle measured to the column longitudinal axis are considered. Using these variables, an equation representing the effective section area of circular transverse shear steel is proposed. The study result shows that the constant parameter. used for the calculation of the effective section area of circular hoops over the last 10 years, should not universally be applied any more. The use of the constant parameter may not seriously do harm to the evaluation of shear strength for circular columns with non-seismically designed transverse hoop reinforcement, since it gives slightly conservative results. However. for well-confined circular columns with close spacing or circular steel jacketing. it gives about 20% overestimation of the shear capacity contributed by the transverse hoop steel.

• Journal of the korean veterinary medical association
• /
• v.32 no.4
• /
• pp.220-233
• /
• 1996

소 해면형 뇌증(Bovine Spongiform Encephalpathy; BSE)은 일명 광우병(mad cow disease)이라고도 불리우는 새로운 해외 가축전염병이며, 세계적인 희귀질병으로 아직까지 확실한 병인체가 밝혀져 있지도 않으며, 그렇기 때문에 면역 혈청학적 진단방법도 확립되어 있지 못할 뿐만아니라 예방백신의 개발 또한 불가능하기 때문에, 일단 감염되어 발병되면 치료대책 없이 100$\%$ 폐사되는 세기의 불치병이다. 본 편에서는 소 해면형 뇌증(BSE)과 관련, 국제수역사무국(OIE) 총회에 보고된 영국정부의 공식보고 자료(Dept of Health, MAFF, 1989) 및 최근의 보고자료(1994, 1995)를 기본으로 하고, 각 회원국의 보고자료(Animal Health Status in Member Countries)와 전산화 역학정보 자료(Handistatus) 등을 근거로 하여, 소 해면형 뇌증이 세계적으로 처음 보고된 1986년 이래 최근 (1996년 3월)까지의 해외발생 역학정보를 수집 분석하고, 아울러 최근 전염병 및 해충의 효과적인 관리를 위하여 새롭게 정립되어 가고 있는 위험도 분석(risk analysis)의 개념을 도입하여, 우리나라에 있어서의 수입 쇠고기의 안전성 문제와 국내에서의 소 해면형 뇌증의 발생 가능성 등에 관하여 고찰해 보고자 한다. 결론적으로 소 해면형 뇌증은 현재 영국(그레이트 브리튼, 북아일랜드 등)에서 가장 크게 문제시 되고 있으며, 유럽 일부국가, 영국으로부터 소를 수입한 극소수의 국가에서 문제가 되었을 뿐, 영국 등 발생국가로부터 소와 쇠고기를 수입하고 있지 않는 우리나라에 있어서는 수입 쇠고기의 안전성에 문제가 없으며, 소 해면형 뇌증이나 양 스크래피의 국내 발생 가능성도 현재로서는 무시할 수 있을 정도로 극히 희박한 것으로 평가된다.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.13 no.3
• /
• pp.373-384
• /
• 2000

To assess the safety of nonlinear steel frame structures subjected to short duration dynamic loadings, especially seismic loading, a nonlinear time domain reliability analysis procedure is proposed in the context of the stochastic finite element concept. In the proposed algorithm, the finite element formulation is combined with concepts of the response surface method, the first order reliability method, and the iterative linear interpolation scheme. This leads to the stochastic finite element concept. Actual earthquake loading time-histories are used to excite structures, enabling a realistic representation of the loading conditions. The assumed stress-based finite element formulation is used to increase its efficiency. The algorithm also has the potential to evaluate the risk associated with any linear or nonlinear structure that can be represented by a finite element algorithm subjected to seismic loading or any short duration dynamic loading. The algorithm is explained with help of an example and verified using the Monte Carlo simulation technique.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.1C
• /
• pp.19-29
• /
• 2008

As a part of study to develop LRFD (Load and Resistance Factor Design) codes for foundation structures in Korea, reliability analyses for driven steel pipe piles are performed and the target reliability indices are selected carefully. The 58 data sets of static load tests and soil property tests conducted in the whole domestic area were collected and analyzed to determine the representative bearing capacities of the piles. The static bearing capacity formula and the Meyerhof method using N values are applied to calculate the expected design bearing capacity of the piles. The resistance bias factors were evaluated for the two static design methods by comparing the representative bearing capacities with the design values. Reliability analysis was performed by two types of advanced methods: First Order Reliability Method (FORM), and Monte Carlo Simulation (MCS) method using resistance bias factor statistics. The static bearing capacity formula exhibited relatively small variation, whereas the Meyerhof method showed relatively high inherent conservatism in the resistance bias factors. Reliability indices for safety factors in the range of 3 to 5 were evaluated respectively as 1.50~2.89 and 1.61~2.72 for both of the static bearing capacity formula and the Meyerhof method. The target reliability indices are selected as 2.0 and 2.33 for group pile case and 2.5 for single pile case, based on the reliability level of the current design practice and considering redundancy of pile group, acceptable risk level, construction quality control, and significance of individual structure.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.5
• /
• pp.527-534
• /
• 2019

Several types of mathematical analysis methods are used for port waterway risk assessment based on marine traffic volume. In Korea, a marine traffic congestion model that standardizes the size of the vessels passing through the port waterway is applied to evaluate the risk of the waterway. For example, when marine traffic congestion is high, risk situations such as collisions are likely to occur. However, a scientific review is required to determine if there is a correlation between high density of maritime traffic and a high risk of waterway incidents. In this study, IWRAP Mk2(IALA official recommendation evaluation model) and a marine traffic congestion model were used to analyze the correlation between port waterway risk and marine traffic congestion in the same area. As a result, the linear function of R2 was calculated as 0.943 and it was determined to be significant. The Pearson correlation coefficient was calculated as 0.971, indicating a strong positive correlation. It was confirmed that the port waterway risk and the marine traffic congestion have a strong correlation due to the influence of the common input variables of each model. It is expected that these results will be used in the development of advanced models for the prediction of port waterway risk assessment.

• Journal of Food Hygiene and Safety
• /
• v.33 no.4
• /
• pp.229-239
• /
• 2018

Currently, in Korea, a dry food simulant has not been designated for the migration testing of paper and board, food contact materials (FCMs) being used in dry foods, and foods heated at ultra-high temperature. Considering the diverse usage of FCMs, in order to secure reliable and confident safety evaluation and to overcome the non-trade barrier tariff in worldwide trade, migration testing methods of what should be more clearly defined for securing and overcoming. This article delves into the available literature on the use of $Tenax^{(R)}$ as a simulant for dry foods as well as its suitability and limitations, and examines the feasibility of its introduction into Korean FCMs regulation. Most experimental studies using $Tenax^{(R)}$ showed overestimated migration values when used in real foods, which reflects the potential of $Tenax^{(R)}$ as a dry food simulant in a worst-case scenario. However, more studies are required to optimize migration testing using $Tenax^{(R)}$ by standardizing the solvent type and the extraction method for surrogates of various FCMs and foods, and to resolve the potential drawbacks in the use of $Tenax^{(R)}$.

• Journal of the Korean Geotechnical Society
• /
• v.21 no.9
• /
• pp.77-86
• /
• 2005

Since slope sliding and loss of railway triggered by a rainfall produce instability in the operation of trains, a proper method to estimate the slope stability considering rainfall Is required. from the field study, sliding induced by rainfall depends on the engineering properties of soils, three dimensional aspect of the slope, rainfall intensity and geological conditions of the soil layers. In this study, among various types of sliding, slope Instability caused by the surface runoff water at the concave zones in a slope is investigated. The depth of runoff water is calculated by using the Rational method and Manning equation. The occurrence of runoff water is evaluated by a comparison between the calculated infiltration rate and rainfall intensity. Pressure heads which can be calculated from the modified Iverson model are used to calculate the factor of safety along the vertical depth of the slope. The modified Iverson model considers the depth of runoff water, thus the maximum hydraulic gradient along the depth of slope is greater than one.

• Korean Journal of Environment and Ecology
• /
• v.8 no.1
• /
• pp.1-10
• /
• 1994

Present problems of the Korean rare and endangered plant species evaluations are discussed. It is proposed that the evaluation criteria for Korean rare and endangered are urgently needed in the future. The translation of new proposed criteria into Korean should be discussed in order to avoid confusion in the future. The draft of a new criteria system for rare and endangered plant species. prepared by the S. S. C. (Species Survival Commission) of I. U. C. N (International Union of Conservation of Nature) are introduced. The proposed draft for the criteria being developed by the S. S. C. of I. U. C. N. are Extinct, Extinct in the Wild, Critical, Endangered, Vulnerable, Susceptible, Safe /Low Risk, Insufficiently Known, and Not Evaluated. It is expected to take the more time to be technically developed further and also officially recognized by the I. U. C. N. for the practical use in the future.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.22 no.7
• /
• pp.791-799
• /
• 2016

The purpose of this work is to analyse the impact of new accident risks on maritime safety in Korea. The new accident risks have been induced from new/rare or unprecedented events in world maritime transportation, as identified by 46 experts in the previous study. To measure the impact of these new accident risks on maritime safety in Korea, the statistical accident data reported by the Korean Maritime Safety Tribunals (KMST) has been used for calculation, and the concept of Risk Index (RI) = Frequency Index (FI) + Severity Index (SI)established in a Formal Safety Assessment (FSA) by the IMO has also been introduced. After calculating two kinds of weight for FI and SI from the statistical accident data, high ranked scenarios were identified and their relationships between new risks and these scenarios were analysed. The results from this analysis showed, the root cause of the top-ranked scenario to be "developing high technology", which leads to "shorten cargo handling time". These results differed from optimum RCOs such as "business competition" and "crewing problems" which were identified in the previous study.