• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.219-224
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• 2006

In this paper, to verify the safety of railway vehicle structure, we describe the test methods of roof structure. The purpose of GM/RT 2100' missile protection article is to minimise the risk of injury which could result from the penetration into a vehicle body by missile such as stones and bricks. we carried out weight drop test on the roof structure in accordance with GM/RT 2100. The test results showed that the penetration did not occer.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1036-1041
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• 2007

In this paper, we studied the optimized design of roof structure to be separable roof structure. Also, the design have to satisfy with the GM/RT 2100' missile protection tests to verify the safety of railway vehicle structure. The separable roof structure design could have easier assembly process than whole roof structure in case of the interior outfitting and so on. Optimized design have to have as good as whole roof structure about results from the structure analysis. We studied separable roof structure to be optimized along with GM/RT 2100. The separable roof structure showed that the results have the same level of structure analysis

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.2145-2150
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• 2008

In this paper, we reviewed comparing GM/RT2100 with UIC566 OR to verify whether the carbody structure has enough strength to withstand the loads specified by GM/RT2100 or UIC566 OR by obtaining stress levels for the loads, checking whether they are within allowable stress limits. The railway vehicles in Europe are applied GM/RT2100 or UIC566 OR for analysis. But many things are different between GM/RT2100 and UIC566 OR. To apply for the railway vehicles in Europe, we reviewed the difference of the both standards.

• 비파괴검사학회지
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• 제30권3호
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• pp.271-281
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• 2010

Brazing fitting which is one of the aircraft hydraulic power system components is widely used for saving weight and achieving higher reliability. Any inherent defects or damage of fitting can cause system failure and/or physical damage of human body due to highly pressurized fluid. Radiographic testing(RT) technique and additional micro-structure investigation on cut-away surfaces have been accomplished to find out some defect-like-inhomogeneity in the fittings. The radiography results showed that some defect-like-inhomogeneity existed inside body. Additional micro-structure investigation on cut-away surface reveals that the inhomogeneity is due to internal voids. In this study, it can be is said that RT technique can be a useful tool for field acceptance test of hydraulic brazing fitting in short time.

• Journal of Welding and Joining
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• 제35권2호
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• pp.63-70
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• 2017

As the Non Destructive Test (NDT) for the welded structure, PT(Penetration Test). MT(Magnetic Test), RT (Radioisotope Test) and UT(Ultrasonic Test) methods are widely used in practice. These NDT methods have been developed toward high efficiency, low cost, real time, and high precise new NDT. For example, RT methods are developed to CT(Computed Tomography)and DR(Digital Radiography), and UT metheds are developed into Phased array, Guide wave, TOFD method. Moreover, the Infrared thermography and Laser ultrasonic technique are newly developed for applying in high temperature objects as the non-contact NDT methods. In this review paper the new high efficiency NDT methods for the welded structure are introduced and the trend of NDT rules applying in welded structure are described.

• 한국환경농학회지
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• 제30권4호
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• pp.367-376
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• 2011

논 토양의 미생물 생태 다양성을 조사하기 위한 효과적인 방법으로 qRT-PCR을 적용하고자 본 연구를 수행하였다. 논 토양 미생물의 gDNA를 분리하기 위하여 Mo Bio kit를 사용한 효과적이고 안정적인 gDNA 분리 방법을 확립하였다. 논 토양 미생물 다양성을 qRT-PCR로 검출하기 위하여 bacteria를 세분한 ${\alpha}$-Proteobacteria, ${\beta}$-Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes 다섯 가지 문과 전체 bacteria, 전체 fungi를 구분할 수 있는 특이 primer set을 선정하여 다양한 조건의 시험을 통하여 최종 조건을 확립하였으며 재현성 실험을 통하여 방법의 유의성을 검증하였다.

• 수산해양기술연구
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• 제44권4호
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• pp.265-272
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• 2008

Biodegradable polybutylene succinate(PBS) is an environment friendly plastics for fisheries, because it can mitigate the ghost fishing problem caused by gill-net and trap fisheries. To evaluate photodegradability of PBS monofilament in comparison with polyamide(PA) and polyethylene(PE) monofilament, these 3 types of monofilaments were spun and exposed to ultraviolet light(UV) of weather-ometer for 900 hours, and then their modification, crystal structure, strength, and extensibility were analysed. PBS monofilament did not show any crack and maintained its crystal structure after 900 hour exposure to UV whereas PE monofilament began showing cracks and structure modification after 600 hour exposure. Under UV exposure, the strength and extensibility decreased more rapidly in PBS than in PA and PE. We estimate that gill nets made of PBS monofilament can endure for about 1 year. The breaking strength and elongation decreased linearly with the exposure time for the 3 types of monofilaments. The derived regression equations of the residual tenacity(RT, kg/$mm^2$) and the residual extensibility(RE, %) with the exposure time in year(Y) for each monofilament were; PBS : RT=48.598 - 8.6437Y($R^2=0.93$), RE=28.165 - 7.3233Y($R^2=0.98$), P A : RT=59.771 - 8.6437Y($R^2=0.98$), RE=32.198 - 5.2772Y($R^2=0.92$), P E : RT=60.898 - 5.6528Y($R^2=0.98$), RE=11.887 - 0.7188Y($R^2=0.98$).

• 한국의학물리학회지:의학물리
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• 제33권4호
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• pp.172-179
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• 2022

Recently, tetrahedral phantoms have been newly adopted as international standard mesh-type reference computational phantoms (MRCPs) by the International Commission on Radiological Protection, and a program has been developed to convert them to computational tomography images and DICOM-RT structure files for application of radiotherapy. Through this program, the use of the tetrahedral standard phantom has become available in clinical practice, but utilization has been difficult due to various library dependencies requiring a lot of time and effort for installation. To overcome this limitation, in this study a newly developed TET2DICOM-GUI, a TET2DICOM program based on a graphical user interface (GUI), was programmed using only the MATLAB language so that it can be used without additional library installation and configuration. The program runs in the same order as TET2DICOM and has been optimized to run on a personal computer in a GUI environment. A tetrahedron-based male international standard human phantom, MRCP-AM, was used to evaluate TET2DICOM-GUI. Conversion into a DICOM-RT dataset applicable in clinical practice in about one hour with a personal computer as a basis was confirmed. Also, the generated DICOM-RT dataset was confirmed to be effectively implemented in the radiotherapy planning system. The program developed in this study is expected to replace actual patient data in future studies.

• BMB Reports
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• 제57권1호
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• pp.40-49
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• 2024

Prokaryotes encode clustered regularly interspaced short palindromic repeat (CRISPR) arrays and CRISPR-associated (Cas) genes as an adaptive immune machinery. CRISPR-Cas systems effectively protect hosts from the invasion of foreign enemies, such as bacteriophages and plasmids. During a process called 'adaptation', non-self-nucleic acid fragments are acquired as spacers between repeats in the host CRISPR array, to establish immunological memory. The highly conserved Cas1-Cas2 complexes function as molecular recorders to integrate spacers in a time course manner, which can subsequently be expressed as crRNAs complexed with Cas effector proteins for the RNA-guided interference pathways. In some of the RNA-targeting type III systems, Cas1 proteins are fused with reverse transcriptase (RT), indicating that RT-Cas1-Cas2 complexes can acquire RNA transcripts for spacer acquisition. In this review, we summarize current studies that focus on the molecular structure and function of the RT-fused Cas1-Cas2 integrase, and its potential applications as a directional RNA-recording tool in cells. Furthermore, we highlight outstanding questions for RT-Cas1-Cas2 studies and future directions for RNA-recording CRISPR technologies.

• 한국재료학회지
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• 제14권2호
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• pp.94-100
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• 2004

We have investigated the magnetic domain structure and the thermal stability of magnetotransport properties of IrMn biased spin-valves containing Co, CoFe and NiFe. The magnetic domain structures were imaged using a magneto-optical indicator film(MOIF) technique. To investigate the thermal stability, magnetoresistance(MR) was measured at annealing temperature(TANN) and room temperature($T_{RT}$) followed by the annealing. Domain imaging reveal that the increase of annealing temperature led to changes in the exchange coupling between the two ferromagnet(FM) layers through nonmagnetic layer rather than between FM and antiferromagnet. unlike the NiFe biased IrMn spin valve with large domains, MOIF pictures of Co and CoFe biased IrMn spin valve structures show the formation of many small microdomains. The magnetic structure, as revealed by the domain images, appeared unchanged while the MR dropped dramatically. From the combined giant magnetoresistance(GMR) and MOIF results, it was apparent that the decrease of MR ratio was not related to the spin valve magnetic structure up to about $350^{\circ}C$($T_{RT}$ ).