• Applied Microscopy
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• v.36 no.3
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• pp.209-216
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• 2006

Accuracy and precision of the goniometer and the specimen holder should be measured and corrected to improve reliability of 3-D structure analysis using transmission electron microscopy (TEM). In this study, we described the operation principle and performance of the Gatan rotation holder. Through analysis of the images taken inside the microscope, rotation angles were measured within the accuracy of ${\pm}0.42^{\circ}$. For comparison the rotation angles were measured outside the microscope using a home-made measurement tool, which resulted in the accuracy of ${\pm}0.6^{\circ}$. Additionally, we found abnormal specimen drifts during rotation probably due to the unstable engagement between the specimen cup and the rotation belt.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.68-77
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• 2012

As the system development environment moves from single core to multi core-based platforms, it becomes more important to maintain compatibility between single core-based implementations and multi core-based implementations. Moreover, it is very important to support real-time on multi core platforms especially in cases of embedded software or test equipments which need real-time as well as correctness. Since Windows operating system dopes not support real-time in itself, it has been supporting real-time using expensive third-party solutions such as RTX or INtime. So as to reduce this kind of development expenses, in this paper, we propose RTiK-MP(Real-Time implant Kernel-Multi Processor) which supports real-time on Windows using the Local APIC of x86 architectures, and evaluate the performance of the proposed RTiK-MP after deploying it on portable missile test equipments.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.189-192
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• 2008

Generally, the inspection is hard work and needs a lot of time. So, this work contains subjectivity of inspector owing to carry out the visual evaluations through naked eye. Thus, the result of inspection is not objective and reliable. The purpose of this study is to develop new inspection technique to solve above problems and to provide convenient inspection work. We make a new inspection system using digital image processing technology. This program can stitch each image and detect cracks of surface of concrete bridge. Also, It can extract an investigation drawing from the picture. Also, this program is a kind of management tools designed to have some functions such as converting the image data obtained from cameras to Data-Base format, searching and storing the data. At first, we try to make a automatic extracting program. But, changed by semiautomatic method because of various problems. Through field experiments, the application of this inspection system with specialty software has proven to be much faster, safer, and reliable than the inspections carried out by the naked eyes in managing safety of the bridges. The new inspection method may be able to make the inspection of bridge more efficient and reliable.

• Journal of Korean Society for Geospatial Information Science
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• v.2 no.1 s.3
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• pp.121-129
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• 1994

A number of existing cadastral control stations have been destroyed and shifted by a long lapse of time and careless management. Also, results of them are partly poor owing to dependence on conventional survey method. Because of these, it is very difficult in use of results. Hereupon, correction of cadastral results is necessary in level of government. But it is very consumable to check and adjust results with existing equipments and related techniques only. It is required that this problem can be resolved efficiently. This study analyzed the conformability for cadastral control network to GPS, GPS, which determine precise 3-D coordinates on a short time, to positioning of cadastral stations. We chose DaeJon city for the test area of this study and analyzed the precision of network composed of sixteen cadastral control stations. We made comparision the old result and the new outcome which obtained from coordinate transformation method and horizontal network adjustment method. As a result of this, we detected the blunder of cadastral stations. Furthermore, we suggested effective network type according to precision analysis of GPS observation network. Therefore, there is no doubt that GPS surveying can be applied to checking and adjustment of cadastral control network. Hereafter, it is expected that the practical use of GPS is advanced in a field of cadastration.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.130-138
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• 2015

According to the "Safety Evaluation Detailed Instructions (Dam)", a precise safety inspection is carried out for dams that exceed a certain scale. However, as the Hydrological Safety Evaluation from various evaluation standards is designed to evaluate the safety of existing dams considering PMF(Probable Maximum Flood), the evaluation is much less applicable for most agricultural reservoirs. Therefore, the Hydrological Safety Guidelines for agricultural reservoirs are expected to be re-evaluated considering the diverse risk factors with the coefficient model and AHP(Analytic Hierarchy Process) in this study. The coefficient model has been developed by selecting the hydrological safety superordinate subordinate evaluation factors to reflect diverse risk factors of agricultural reservoirs. This study indicated that in the short term, improving the safety check condition evaluation grade will be useful to improve the hydrological safety of the agricultural reservoir because it can be performed immediately.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.98-106
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• 2020

This study examined the integrity of diesel engines for underwater vessels through failure analysis, analyzed the causes of abnormal diesel engine stoppage during building and examined the integrity of secondary damages. The diesel engine stoppage was analyzed by checking the temperature change of the piston before and after the abnormality and checking the damage. In addition, in order to analyze the secondary damage caused by the explosion, the tensile and compressive stresses transmitted to the crankshaft, the core part of the diesel engine, were calculated, and the stress distribution was examined through finite element analysis, but the crankshaft was designed by safety. It was confirmed that there was no damage to the crankcase even when the diesel engine was taken out of the ship and closely inspected. The integrity of the crank shaft was verified in advance for the occurrence of diesel engine emergency shutdown accidents through this research result. Therefore, the inspection and restoration were carried out to the minimum extent, and the quality of diesel engines was secured. This study is expected to be used as a reference for ensuring soundness in any future review of diesel engine quality problems.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.232-249
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• 2022

The purpose of this article is to review the status of designation and preservation, management of national prehistoric sites and to suggest future applications. Prior to the discussion, the overall status of national prehistoric sites was reviewed. Specifically, the current status of designation, designated area, and distribution by region of national prehistoric sites according to the period and nature of the sites were examined in detail. Next, in order to understand the preservation and management of national prehistoric sites, I report the results of field trips to several sites, such as Geomdan-ri in Ulju, Songguk-ri in Buyeo, and Seoktaek-ri in Hongseong, and propose some measures for preservation, maintenance, and management of the remains. Finally, by referring to cases of US national historic sites such as protection, conservation, operation and management system and academic research project of cultural heritage, it is necessary to consider the need for a direction of the utilization that considers both socio-economic aspects as well as education and research on cultural heritage. The active use of cultural heritage can be a measure that leads to the continuous preservation and management of the sites, and ultimately will be a shortcut to increasing the value of national prehistoric sites.

• Journal of the Korean Society for Precision Engineering
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• v.4 no.2
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• pp.17-19
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• 1987

지난해 우리나라 경제는 안정속에 고도성장과 국제수지 흑자를 기록한 값진 보람을 느낀 한 해였다. 그러나 이같은 흑자기조는 개개기업의 성장잠재력에서 찾아볼 수도 있겠으나 대부분이 3저요인을 배경으로한 수출환경의 변화에 힘입은 바 크다. 그럼으로 언제 무산될지 모르는 장래를 낙관만 할 수는 없다. 지금의 현상을 어떻게 보는가에 대하여는 각계각층이 보는 시각에 따라 견해가 달라지겠으나 분명한 것은 국제유가나 국제이자가 오름세를 보이기 시작했다는 사실과 우리에게 국제경상수지흑자시대를 열어준 3저호재는 확실히 변해가고 있다는 것이다. 이렇게 볼 때 우리나라 경제는 해외요인변화에 매우 예민함으로 지금, 흑자기조가 정착되었다고 속단하기에는 너무 이른것 같다. 적어도 흑자기조가 정착되려면 모든 산업간, 계층간, 지역간의 불균형이 시정되고 기존의 산업기반을 내실화하는 단계에 있을 때 비로서 흑자경제의 향배가 가름하게 되는 것이다. 최근에 일어나고 있는 원화의 지속적인 평가절하, 엔화강세에 따른 원자재가격폭등은 우리에게 적지않은 위협을 주고있다. 이같은 상황에서 정부는 올해 국제수지흑자의 적정선유지를 위해 대미구매사절단의 파견, 수입선의 다변화, 수출지원정책의 감소등 다각적인 정책을 선택하고 있는 것으로써 일응 올바른 판단으로 수긍하나 다만 업종에 따른 특성에 배려가 있었으면 한다. 특히 우리나라의 기계공업은 20년의 짧은 근대화건설 과정에서 그나마 지금의 수준과 규모의 기반을 닦아왔다. 그러나 아직도 기술면에서 많은 취약점을 지니고 있어 대부분의 기초소재와 핵심부품이 해외에서 수입되고 있는 실정이다. 따라서 기계공업이 명실공히 선도산업으로써 의 위치를 굳히기 위해서는 적어도 기계류의 수입국에서 수출국으로의 탈바꿈을 할 때 비로소 성취될 것이며, 이 때가 관련산업간의 불균형이 시정된 흑자시대라고 보는 것이 옳을 것 같다. 작금의 주변환경은 서두에서 언급한 3저호재에 심상치 않는 조짐이 보이고 있다. 이같은 주변환경에 관점을 두고 지금 우리가 당면하고 있는 과제 중의 하나인 원화절상을 지적하지 않을 수 없다. 이같은 원화절상내용을 중심으로 부가적으로 수반된 몇가지의 현안문제와 함께 점검해 보기로한다.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.942-946
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• 2007

The new gravity field combination models are expected to improve the knowledge of the Earth's global gravity field. This study evaluates six global gravity field models derived from gravimetry and altimetry surface data in a comparison with ground truth in South Korea. For calculating a more accurate estimate of the geoid heights from the height anomalies, the terrain corrections due to the terrain masses over geoid have considered, the model for the topographic correction is a spherical harmonic expansion of the ETOPO2 DTM model. Geoid heights obtained from GPS and levelling in land area of South Korea are compared with those from the EGMs. The results show that EIGEN-CG03C EGM and EIGEN-GL04C EGM displayed the nearest results to GPS/leveling, and also confirmed the importance of terrain correction for geoid height in case of the uneven topography.

• Fire Science and Engineering
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• v.23 no.5
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• pp.125-132
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• 2009

In this study we could contribute to the development of a precise checking tool with which the reliability of the automatic fire detection systems was enhanced and the safety of the people was ensured. In the same way as the domestic technical standard, the portable smoke sensitivity tester, which was developed in this work, could be used to check the capability of the smoke detectors installed in the field. Its heater inside was warmed up to $400^{\circ}C$ in 40 seconds and the paper as a smoke source was burned to produce smoke for the test. With the Photoelectric smoke detector it was possible to measure and control the smoke concentration in a range from 0%/m to 25%/m. With the adjustment of rpm of the fan, it was possible to keep a constant wind velocity in a range from 20cm/sec to 40cm/sec.