• 한국환경성돌연변이발암원학회지
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• 제17권2호
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• pp.71-77
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• 1997

The single cell gel electrophoressis(SCGE) assay, also known as the comet assay, is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakage in mammalian cells. The SCGE or comet assay is a promising test for the detection of DNA damage and repair in individnal cells. It has widespread potential applications in DNA damage and repair studies, genotoxicity testing and biomonitoring. In this microgel electrophoresis technique, cells are embedded in agarose gel on microscope slides, iysed and electrophoresed under alkaline conditions. Cells with increased DNA damage display increased migration of DNA from the nucleus towards the anode. The length of DNA migration indicates the amount of DNA breakage in the cell. The comet assay is also capable of identifying apoptotic cells which contain highly fragmented DNA. Here we review the development of the SCGE assay, existing protocols for the detection and analysis of comets, the relevant underlying principles determining the behaviour of DNA and the potential applications of the technique.

• 항공우주시스템공학회지
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• 제6권3호
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• pp.13-18
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• 2012

Every 3000 hour an aircraft is stricken by a lightning. Also the lightning damage to the aircraft during flight are continually occurred due to extreme weather phenomena such as global warming. Under the airworthiness standards, the aircraft must be designed to protect lightning. To show compliance for lightning, the test should be conducted by the actual lightning current and voltage waveform for the actual aircraft or parts. After test, structure damage is detected via visual inspection or NDI. Structure substantiation for damage is to show retaining limit or near limit load capability. This is conducted by test or analysis based on test. Thus, the aircraft should retain structural strength to land safely, even though the damage of aircraft fuselage from Lightning strike are occurred.

• 한국산림과학회지
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• 제89권2호
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• pp.145-160
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• 2000

우리나라의 대표적인 해안형국립공원이라 할 수 있는 한려해상국렵공원의 경관자원을 대상으로 시각자원관리를 위한 객관화된 정량적인 기초자료를 제시하는 것을 목적으로 설정된 가설과 실험에 의한 검증과정을 실시하였다. 이에 따라 공간구성요소의 물리량을 메쉬 (Mesh)분석법에 의한 시각량과, S.B.E. Method에 의한 시각적 선호도를 측정하고 시각자원의 가치를 Iverson 법에 의하여 분석하였다. 심리량 분석을 위해 S.D Scale 측정에 의한 공간의 이마지구조를 인자분석 Algorithm을 통하여 밝혔으며 시각적 선호도 측정을 실시하여 결정인자추출과 각 인자 상호간 상대적 중요성을 규명하였다. 한려해상국립공원의 자연경관과 융화를 전제로 한 수림, 하늘, 수면, 기암괴석 등의 자연요소와 인공구조물 등의 요소를 지닌 시각요소가 긍정적으로 높게 나타날 수 있도록 대상지향성과 형수성을 높일 수 있는 체험의 장을 이루게 하여 경관적 가치를 높이며, 인공구조물 요소에 대한 보다 계획적이고 체계적인 설치 등의 경관자원관리 기법이 필요하다 하겠다. 한려해상국립공원 경관자원관리 개선방안의 측면에서 볼 때 인간간섭이 과다하게 되면 식생을 파괴하게 되어 자연경관의 질을 떨어뜨리게 되기 때문에 구체저이고도 명확한 관리목표를 설정하여 합리적인 수준의 개발이 이루어져야 하고, 적정이용수를 산정하여 적정이용수의 범위내에서 출입을 허용하여야 할 것이다. 다만 관리목표는 수준별로 설치, 적극적 관리, 매우 적극적 관리의 3단계 목표를 설정하여 허용할 수 있는 변화의 한계로 인식되어야 할 것이다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2862-2867
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• 2008

High-temperature components of gas turbine operated for certain period of time can be reused by being repaired or rejuvenated. In case of the gas turbine combustion liners, the biggest and the most important one in the high-temperature components, come in a repair shop after operated for 8,000 or 12,000 hours according to the model and go through the repair and rejuvenation in order to be reused. A stated combustion liner is the first channel which has the combustion gas reached a nozzle from a fuel nozzle. Materials and coating properties of old and new model combustion liners were investigated. To repair these components after the visual inspection, the coatings of combustion liners were removed and then FPI(Fluorescent Penetrant Inspection), a kind of the NDI(Non-Destructive Inspection), was conducted. Damage patterns and the number of the damaged components were classified and analyzed based on data provided from the visual inspection over a long period of time. Focusing on the difference between old model and new model combustion liners, we analyzed the damage distribution and changes and consequently concluded that new model combustion liner would increase repair rate.

• 한국지반공학회논문집
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• 제20권1호
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• pp.49-59
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• 2004

본 논문에서는 도심지에서의 터널 시공에 따른 지반거동을 평가하고 이에 따른 인접 건물 혹은 매설관의 위험도를 평가하는 GIS기반의 위험도 관리 시스템(GIS-TURIMS) 개발에 대한 내용을 다루었다. 본 시스템은 상용 GIS 소프트웨어인 ArcView 8.1을 기반으로 개발되었고, VB(Visual Basic)와 VBA(Visual Basic Application)를 사용하여 터널시공으로 인한 지반거동과 건물 손상정도의 공학적 연산을 수행할 수 있도록 하였다. 개발된 시스템은 GIS기술의 장점을 최대한 활용하여 터널 시공으로 인한 지반거동, 건물/매설관 손상평가의 강력한 해석을 수행할 수 있도록 하였다. 본 논문에서는 GIS-TURIMS의 개요와 개발과정에 대하여 상세히 다루었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.577-582
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• 2001

Identification of damage of structures has recently received considerable attention in the light of maintenance and safety assessment under service loads. In buildings, the current techniques of safety assessment largely depend on partial experiments such as visual inspection, destructive and nondestructive tests which lead to overconsumption of time and cost as well as higher labor intensity. Therefore, a new trial for safety assessment is urgently needed today. In this respect, the vibration characteristics of buildings have been applied steadily to obtain a damage index of the whole building, but it cannot be established as a practical method until now. This study is aimed at investigating the application of damage identification methods using vibration characteristics of building. Numerical tests are performed on a apartment building. From the test results, it is observed that severity and location of damage can be estimated with a relatively small error by using natural frequency and mode shape data.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.65-66
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• 2017

Early-frost damages easily take place in smaller and thinner walls and slabs. In case of slabs, it is difficult to visually determine the depth of early-frost damage. As such, the current study aims to determine the depth of early-frost damage caused to concrete structures due to bad curing in the winter. As a result, the study found that the depth of early-frost damages increased from the top as the atmospheric temperature on the concrete surface decreased. The changes in the color allowed the observer to easily identify the depth of early-frost damage with the naked eye. In particular, the color difference between potentially damaged parts and undamaged parts were the greatest around thirty minutes of drying after wetting.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1206-1208
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• 2003

The extraction of earthquake damage from remote sensed imagery requires high spatial resolution and temporal effectiveness of acquisition of imagery. The analog photographs and visual interpretation were taken traditionally. Now it is possible to acquire damage information from many commercial high resolution RS satellites. The key techniques are processing velocity and precision. The authors developed the automatic / semiautomatic image process techniques including feature enhancement, and classification, designed the emergency Earthquake Damage and Losses Evaluate System based on Remote Sensing (RSEDLES). The paper introduced the functions of RSEDLES as well as its application to the earthquakes occurred recently.

• Journal of Biosystems Engineering
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• 제40권4호
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• pp.409-416
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• 2015

Purpose: This study evaluates a new banana bulk packaging method under the real transport conditions of Sri Lanka. Methods: A field evaluation of optimized 8-mm thick Styrofoam sheets used as the cushioning material was applied. A trial transport was conducted from Thambuttegama to Colombo using a medium-sized open truck, with banana leaves as the control material. Data were recorded at the farmer, transporter, retailer, and consumer stages of the supply chain. Mechanical damage, physiological loss in weight, fruit firmness, total soluble solids, ripeness index, visual quality ratings, and the physical damage index of the bananas were measured at each stage. A cost-benefit analysis was also conducted for both packaging methods. Results: The 8-mm styrofoam sheets significantly reduced (p < 0.05) the mechanical damage from 26.3% to 12.9% compared to the conventional method for long-distance transport, and the physiological loss in weight showed a decrease of 2.88%. The loss of firmness of the fruits followed a simmilar pattern for both methods until reaching the retailer, but at the consumer was significantly higher (p < 0.05) for the control. However, the physical damage index at the retail stage for the control showed symptoms of physical injury, whereas the bananas transported using the cushioning materials exhibited only minor symptoms. Further, the visual quality of the fruits after transport from the farmer to the consumer was preserved, which is one of the main factors affecting consumer preference and retail price. The proposed method increases the profit margin by 51.2% for Embul bananas owing to the reduced postharvest losses. Conclusion: The 8-mm thick Styrofoam sheets reduced the physical damage to the bananas, with the quality parameters maintained at the prefered level. Moreover, profits may be increased.

• Structural Engineering and Mechanics
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• 제25권1호
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• pp.39-52
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• 2007

This paper describes an experimental study on structural health monitoring of a 1:3-scaled one-story concrete frame subjected to seismic damage and retrofit. The structure is tested on a shaking table by exerting successively enhanced earthquake excitations until severe damage, and then retrofitted using fiber-reinforced polymers (FRP). The modal properties of the tested structure at trifling, moderate, severe damage and strengthening stages are measured by subjecting it to a small-amplitude white-noise excitation after each earthquake attack. Making use of the measured global modal frequencies and a validated finite element model of the tested structure, a neural network method is developed to quantitatively identify the stiffness reduction due to damage and the stiffness enhancement due to strengthening. The identification results are compared with 'true' damage severities that are defined and determined based on visual inspection and local impact testing. It is shown that by the use of FRP retrofit, the stiffness of the severely damaged structure can be recovered to the level as in the trifling damage stage.