• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.380-388
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• 2016

This study suggests methods to evaluate the availability of anchorage in Ulsan port and determine the proper capacity of future anchorage in accordance with port development. Accordingly, the concept of an Anchorage Operating Rate (AOR) is introduced to evaluate the capacity of anchorage that was available in Ulsan port in 2014. Calculations revealed that the operating rate of all anchorages in Ulsan port did not exceed 100 %. However, in 2020 it is estimated that the AOR at E1 anchorage will be the highest with a rate of 168.3 %, followed by E3 with 131.1 %, E2 with 118.5 % and M with 108.7%. These findings indicate a shortage of anchorage by 2020. In order to decrease the AOR to a level that will not exceed 100 %, in accordance with port development in Ulsan, areas to accommodate an additional 11 ships at E1 anchorage, 1 ship at E2 anchorage, 2 ships at E3 anchorage and 1 ship at M anchorage will be necessary.

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.131-140
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• 2012

Lane markings such as edgelines, centerlines, and lines that delineate lanes generally provide drivers with the various information for safe driving. Drivers can easily recognize the lane markings through the color differences between the markings and road surfaces during the daytime. However, it is a bit difficult for drivers to perceive them during the nighttime due to the lack of artificial lights. Although the glass beads with the 1.5-refractive index have been used to improve the visibility of the lane markings during the nighttime, it is still difficult for drivers to recognize the lane markings properly, especially during the rainy nighttime, which may often lead to traffic accidents. To improve the retroreflectivity and visibility of the lane markings during the rainy nighttime, the high refractive beads with the 2.4-refractive index are essentially required, but they do not work appropriately during the dry nighttime. Thus, the mixed materials with the 1.5, 1.9, and 2.4-refractive beads should be considered for the satisfactory implementation of the lane markings. This study reveals the best mixing rates of the beads by conducting benefit-cost analysis under various weather conditions in Korea. The analysis results show that the lane markings with the 100% of the 2.4-refractive beads provide the highest visibility of lane markings regardless of the roadway conditions, but the benefit-cost (B/C) ratio of the bead mixture is merely 0.46. The best mixing rate of the beads, from the highest B/C ratio viewpoint, was identified as the mixture with a 80% of 1.5-refractive beads and a 20% of 2.4-refractive beads. Some limitations and future research agenda have also been discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.215-222
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• 2018

This study aims to compare and analyze the quality of life of residents between those living in coastal and non-coastal areas. The indicators for the quality of life were divided into three different sectors. First, the economic sector observed the rate of population growth, the number of businesses per 1000 people, the employment and unemployment rate. The second was the environmental sector, which included the number of car registrations per capita, water supply and sewer service ratio, the urban park composition area per 1000 people and the road pavement rate. Thirdly, the social sector comprising data about the number of students per teacher, the number of sickbeds in medical institutions per 1000 people, the rate of traffic accidents per 1000 cars and the portion of social welfare budget in general accounting. The analysis method of standardized indicators and T-Test were carried out in 24 coastal cities and 51 non-coastal cities across the country. Results of the indicator comparison suggested there were significant differences in the number of businesses per 1000 people, the road pavement rate and the rate of traffic accidents per 1000 cars. From the results of each sector comparison, the coastal cities showed a higher value than non-coastal cities only in the economic sector. The quality of life comparison showed that coastal cities were better than non-coastal cities but were not statistically significant.

• Journal of Food Hygiene and Safety
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• v.37 no.5
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• pp.347-355
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• 2022

Levels of beauvericin (BEA) and enniatins (ENNs: ENA, ENA1, ENB, and ENB1) were examined in fresh ginger (n = 43) and ginger powder (n = 31) samples from Korea. In the ginger samples, incidence of BEA contamination was highest, at 62.79%, with a maximum detected BEA level of 640.07 ㎍/kg. ENNs in were found in up to 11.63% (ENB, ENB1) of ginger samples, with a maximum detected level of 91.02 ㎍/kg (ENA). In the ginger powders, ENB contamination displayed the highest rate of incidence (70.97%), but the highest level of BEA (1,344.18 ㎍/kg) exceeded that of ENB (413.99 ㎍/kg). The incidences of ENA, ENA1, ENB, and ENB1 presence in ginger powders were 29.03%, 22.58%, 70.97%, and 35.48%, respectively, and their highest detected levels were 220.45, 156.61, 413.99, and 70.29 ㎍/kg, respectively. The incidence of BEA and ENN contamination was higher in ginger powder than in ginger. Respective co-occurrence rates of BEA and ENNs in ginger and ginger powder samples were 16.28% and 64.52%, indicating that the BEA and ENN co-contamination rate was highest in ginger powder as well. This is the first report on the presence and co-occurrence of BEA and ENNs in Korean ginger and ginger powder.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.4
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• pp.117-128
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• 2016

Installation of earth grounding system is essential to ensure personnel safety and correct operation of electrical equipment. Earth parameters, especially, soil resistivity has to be determined in designing an efficient earth grounding system. The most common applied technique to measure soil resistance is Wenner four-point method. Implementation of this method is expensive, time consuming and cumbersome as large set of measurements with variable electrode spacing are required to obtain a one dimensional resistivity plot. It is advantageous to have a method which is of low cost and provides fast measurements. In this perspective, electrical resistance tomography (ERT) is applied to estimate subsurface resistivity profile. Electrical resistance tomograms characterize the soil resistivity distribution based on the measurements from electrodes placed in the region of interest. The nonlinear ill-posed inverse problem is solved using iterated Gauss-Newton method with Tikhonov regularization. Through extensive numerical simulations, it is found that ERT offers promising performance in estimating the three-dimensional soil resistivity distribution.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.29-32
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• 2007

본 논문에서는 게임에 사용되는 원리를 역으로 적용하여 교통안전 표지판을 인식하는 시스템을 구현하였다. 본 시스템에 사용된 게임은 제작자가 (x, y)좌표에 제공하는 수치를 보고 메쉬에 표시하면 제작자가 의도한 임의의 물체의 모형이 표현되는 게임이다. 입력된 영상으로부터 교통안전 표지판 영상을 분리한 후, 표지판을 구성하는 색상과 형태에 상기의 퍼즐게임을 이용하여 교통안전 표지판으로 인식되면 해당 표지판과 내용을 문자로 출력하는 시스템을 구현하였으며 흑백 영상 처리 및 세선화과정 없는 인식으로 처리 속도가 빠르며, 기존 시스템 보다 좋은 인식률을 얻을 수 있었다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.05a
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• pp.85-90
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• 1997

시스템의 안전성을 확보하기 위하여 각 부품들은 주기적으로 점검되어야 하고, 필요시 교체되어야 한다. 시스템의 신뢰성은 부품 고장률, 점검주기, 점검시간, 인적오류의 함수이다. 시스템의 너무 잦은 보수점검은 보수시 인적오류가능성을 증대시켜 시스템의 신뢰성을 저하시키는 효과가 있으며, 반면에 너무 긴 주기를 갖는 보수점검도 고장시스템을 적시에 찾아내어 교체하지 못함으로 인하여 시스템의 신뢰성이 감소하게된다. 그러므로 적절한 점검주기와 허용정지시간으로 보수되어야 시스템의 효율성과 안전성을 제고시킬 수 있다. 본 논문에서는 이러한 시스템 신뢰성에 영향을 미치는 요소들을 함수로하는 시스템 신뢰성의 해석식을 유도하였고 유도된 수식을 예제시스템인 가스정압기에 적용하였다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.3864-3868
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• 2012

In this paper, a safety valve was modeled by using 3-dimensional designing program, Solidsworks after it was dismantled and measured. And 3-dimensional finite element analysis code, ANSYS was used to FEM analysis. Stress, strain and deformation were obtained when some amount of pressure was applied to the safety valve through FEM analysis.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10d
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• pp.700-702
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• 2002

원자력발전소 1차계통 주요기기와 2차계통 주요기기들에 대한 가동 중 검사시 발견된 결함은 ASME Sec. XI, IWB와 IWC에 근거하여 허용여부를 결정한다. 이때, 결함 크기가 허용기준을 초과하는 경우에는, 기기의 안전성 확보를 위해 ASME Sec. XI에 규정된 절차에 따라 파괴역학분석(Fracture Mechanics Analysis: FMA)을 수행하고, 그 결과에 따라 운전중지 후 보수 또는 계속운전의 판단을 한다. 따라서, 원자력발전소 주요기기에 대한 FMA기술은 안전성평가의 핵심이 되는 부분이다. 원자력발전소의 안전성평가에는 결함의 형상 정보, 환경 정보, 재료 물성치, 응력 데이터 등 방대한 양의 데이터가 필요할 뿐 아니라 파괴역학적 분석절차도 매우 복잡하여 전문가도 많은 시간과 노력이 요구된다. 이러한 문제점을 해결하고자 일부 평가절차를 컴퓨터 프로그램화하여 효율적인 안전성평가가 이루어지도록 노력하고 있다. 본 논문에서는 파괴역학적 분석에 필요한 응력 데이터를 관리하는 응력 데이터베이스를 구축하고, 응력확대계수계산 프로그램(KEVA)과 결함허용여부를 결정하는 프로그램(Acceptance Standard)과 결함성장률 계산 프로그램(FLEVA)을 Web 기반으로 개발하고 구현결과를 소개한다.

• RED RIBBON
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• s.63
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• pp.10-13
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• 2005

증가하는 HIV/AIDS 감염과 그로 인한 파괴적 결과는 세계적 관심사가 되었고, 발병률이 높은 지역에서 AIDS는 보건의료 문제를 넘어서 국민총생산을 감소시키는 사회경제적 문제가 되고 있다. 한국은 상대적으로 HIV감염 AIDS 발병률이 낮은 나라지만 당초 예상과는 달리 그 발병률이 둔화되고 있지 않으며, 1999년 이후 최근에는 감염자의 수가 급격히 증가하는 추세에 있다. 세계 다른 나라들이나 아시아의 주변국의 사정을 보면 우리나라도 결코 안전한 권역에 계속 머물러 있으리라는 장담을 하기가 어렵다. 특히 근년에 경제적 생산력이 왕성한 $20\~30$대 남성에서 HIV/ADIS 증가하고 있어, HIV/AIDS감염의 사회적 비용, 그 중에 특히 경제적 영향에 대한 관심이 커지고 있는 상황이다. 따라서 우리나라에서 발생하는 HIV/AIDS의 경제적 비용을 추산함으로써 증가하는 HIV/AIDS감염의 경제적 의미를 찾을 필요가 있다고 판단된다. 경제적 비용의 추산에 앞서 우선 우리나라 HIV/AIDS 감염자 수를 추계하여 보면 다음과 같다.