• 해양환경안전학회지
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• 제24권3호
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• pp.367-372
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• 2018

The objective of this paper is to optimize the cross-section of aluminum decking units used in the bass boats under operating conditions, and to verify the optimized model from the results via by ANSYS software. Aluminum decking unit is needed to endure specific loading while leisure activity and sailing. For a stiffer and more cost-neutral aluminum decking unit, optimization is often considered in the naval and marine industries. This optimization of the aluminum decking unit is performed using the ANSYS program, which is based on the topology optimization method. The generation of finite element models and stress evaluations are conducted using the ANSYS Multiphysics module, which is based on the Finite Element Method (FEM). Through such a series of studies, it was possible to determine the most suitable case for satisfying the structural strength found among the phase-optimized aluminum deck units in bass boats. From these optimization results, CASE 1 shows the best solution in comparison with the other cases for this optimization. By linking the topology optimization with the structural strength analysis, the optimal solution can be found in a relatively short amount of time, and these procedures are expected to be applicable to many fields of engineering.

• 한국군사과학기술학회지
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• 제15권1호
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• pp.36-45
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• 2012

In this thesis, we propose an integrated simulation method of virtual tank simulators and an entity-based constructive simulation model for small unit tactical training. To do this, we first identify requirements for virtual-constructive integrated simulation in a synthetic environment. We then propose a virtual and constructive interoperation method where individual combat entities of virtual-constructive models are interacting with each others. We develop a method of aggregating individual combat entities into a larger combat unit and disaggregating an unit into entities from time to time. We also present a way of sharing synthetic environment information between the models. Finally, we suggest that for more effective interoperability, virtual and constructive models should be developed by using common combat object models. The proposed interoperation method can be extended to further live-virtual-constructive models.

• 한국초등수학교육학회지
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• 제14권3호
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• pp.827-842
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• 2010

이 논문에서는 초등학교 4학년 수학과 교육과정에서 제시하는 '무늬 만들기'의 교수학적 변환과 각색의 실제를 비판적으로 검토한다. 무늬 만들기에서의 그 무늬는 일반적으로 벽지무늬가 아니다 그것을 만드는 방식도 벽지무늬를 만드는 방식과 같지 않다. 벽지무늬 만들기가 아니라는 점에서 보면, 새로운 무늬 만들기의 맥락은 '투명 스티커 붙이기'라고 할 수 있다. 이 논문에서는 이 특정을 전제로 해서 단위조각의 모양, 새로운 무늬 만들기의 방법, 단위조각 이어 붙이기의 규칙에 관해 비판적으로 논의하고 있다 단위조각의 모양은 실질적으로 정사각형이 아니면 안된다. 주어진 단위조각을 사용하여 새로운 무늬를 만들 때, 만드는 방식의 규칙성만 제시할 수 있으면 실제로는 어떤 규칙이라도 무방하다. 주어진 단위조각으로 만드는 새로운 무늬와 벽지무늬 사이의 관계는 분명하지 않지만, 그 둘이 서로 무관하다고 보기 어렵다는 점에서, 무늬 만들기가 '잘못된 초등화(Freudenthal, 1973)'의 한 모습일 수도 있다.

• KIEAE Journal
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• 제12권6호
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• pp.77-84
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• 2012

The current architectural design of unit modular has been based on 2D of CAD program, so unit modular character which needs unit information management, as a dried-member system, has no effect on design process. The purpose of this study is We have developed a suitable BIM design process, according to various works of construction, then tried to contribute to supply and activation of the urban-life-housing based on unit modular. The BIM modeling process based on unit modular has been in order of unit combination with preparing manual classification, and, it has been constructed, at construction site, from housing foundation to roof finish by Bottom-up method. At a manufacturing factory, it has been produced in order of 1) grouping materials and parts, 2) fabricating unit boxes, and 3) interference examination of unit boxes, and each order has been classified as housing structure, architecture, plumbing process separately. At a construction site, the fabrication has been done in order of, like as a real housing construction scenario, 1) RC foundation work 2) unit module job-site-fabrication work, 3) roof truss work, 4) plumbing and HVAC work, and 5) housing interior finish work. After modeling process, the interference examination on each work of construction has finally completed modeling. The Unit modular utilizing BIM modeling can make easy housing maintenance through systematic control with preparing manual of unit module information, and securing accurate and speedy construction information. And it will promote design credibility and create maximum effect of unit modular construction method, such as construction period reduction and upgrade of construction quality, etc., through the computer simulation as real as construction environment in cyber space, and with the interfering examination.

• Elastomers and Composites
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• 제49권2호
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• pp.103-109
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• 2014

유화중합 SBR (E-SBR)과 용액중합 SBR (S-SBR) 블렌드를 제조하여 이들의 미세구조(styrene, 1,2-unit, cis-1,4-unit, 그리고 trans-1,4-unit 함량)를 투과 방식 휴리에 변환 적외선 분광법(FTIR)을 이용하여 분석하였다. Valley-to-valley 바탕선으로 흡광도를 측정하는 방법(TV)이 객관적으로 가장 타당한 방법이나 cis-1,4-unit의 피크 세기를 정확히 측정할 수 없는 단점이 있다. cis-1,4-Unit이 포함된 4가지 미세구조에 대한 정보를 얻기 위해, 바탕선을 보정하지 않은 방법(TM)과 최대 투과도를 99%로 조정한 방법(TB)을 TV 방법과 비교하였다. TB 방법으로 구한 결과가 TM 방법으로 구한 결과보다 TV 방법으로 구한 결과와 좀 더 가깝게 나타났다. TM 방법과 TB 방법으로 구한 흡광도를 ISO/FDIS 21561:2005(E)에 제시한 계산식을 이용하여 미세구조 함량을 결정하였다. E-SBR/S-SBR 블렌드 비에 따른 styrene, 1,2-unit, 그리고 trans-1,4-unit 함량의 변화는 비교적 선형성을 보였으며, TM 방법과 TB 방법으로 얻은 결과에는 큰 차이가 없었다. cis-1,4-Unit 함량의 변화는 TM 방법과 TB 방법에 상관없이 직선성이 전혀 나타나지 않았다.

• 식물병연구
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• 제21권3호
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• pp.180-185
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• 2015

In the present work, a pair of primers specific to Tomato yellow leaf curl virus (TYLCV) was designed to allow specific amplification of DNA fragments from any TYLCV isolates using an extensive alignment of the complete genome sequences of TYLCV isolates deposited in the GenBank database. A pair of primers which allows the specific amplification of tomato ${\beta}$-tubulin gene was also analyzed as an internal PCR control. A duplex PCR method with the developed primer sets showed that TYLCV could be directly detected from the leaf crude sap of infected tomato plants. In addition, our developed duplex PCR method could determine PCR errors for TYLCV diagnosis, suggesting that this duplex PCR method with the primer sets is a good tool for specific and sensitive TYLCV diagnosis. The developed duplex PCR method was further verified from tomato samples collected from some farms in Korea, suggesting that this developed PCR method is a simple and reliable tool for rapid and large-scale TYLCV detections in tomato plants.

• 한국건축시공학회지
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• 제16권1호
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• pp.87-96
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• 2016

More than half of Korea's urban population currently lives in multi-unit dwellings. This particular residence structure inevitably positions the living spaces of residents in close proximity to one another. Because of this proximity, the sounds of a particular household will transfer to other residents' units creating conflict between tenants. Efforts to alleviate this problem have been made in both the public and private sector. A prominent method of noise analysis between living units has been to make an actual sound measurement and obtain qualitative measurements from questionnaires. Although this method has been most widely used, such analysis requires a large amount of human effort and time. In addition, the questionnaire method fails to provide the objective information needed to accurately assess the noise situation. To overcome the inadequacies of this previous method, this study seeks to evaluate the applicability of an acoustic simulation method. Three types of living noises were analyzed to assess the noise levels passed between multi-unit dwellings. The acoustic simulation method was found to be more economical, efficient, and adaptable in information processing. The results of this study can be further applied to design and control living-noise through procedures such as acoustic absorption or space redesign.

• Nuclear Engineering and Technology
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• 제53권4호
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• pp.1146-1156
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• 2021

Single-unit probabilistic safety assessment (SUPSA) has complex Boolean logic equations for accident sequences. Multi-unit probabilistic safety assessment (MUPSA) model is developed by revising and combining SUPSA models in order to reflect plant state combinations (PSCs). These PSCs represent combinations of core damage and non-core damage states of nuclear power plants (NPPs). Since all these Boolean logic equations have complemented gates (not gates), it is not easy to generate exact Boolean solutions. Delete-term approximation method (DTAM) has been widely applied for generating approximate minimal cut sets (MCSs) from the complex Boolean logic equations with complemented gates. By applying DTAM, approximate conditional core damage probability (CCDP) has been calculated in SUPSA and MUPSA. It was found that CCDP calculated by DTAM was overestimated when complemented gates have non-rare events. Especially, the CCDP overestimation drastically increases if seismic SUPSA or MUPSA has complemented gates with many non-rare events. The objective of this study is to suggest a new quantification method named probability subtraction method (PSM) that replaces DTAM. The PSM calculates accurate CCDP even when SUPSA or MUPSA has complemented gates with many non-rare events. In this paper, the PSM is explained, and the accuracy of the PSM is validated by its applications to a few MUPSAs.

• The Journal of Advanced Prosthodontics
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• 제9권2호
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• pp.124-129
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• 2017

PURPOSE. This study evaluated the effect of span length on the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques. MATERIALS AND METHODS. Models with two solid abutment analogs at different inter-abutment distances were digitized using a laboratory scanner. Frameworks of two-, three-, and four-unit fixed prostheses were designed by a computer. Six dots with a diameter of 0.2 mm were preset on the surface of each framework. A total of 54 implant-supported cobalt chromium frameworks were fabricated by milling, selective laser melting (SLM), and cast techniques. The frameworks were scanned and exported as Stereolithography files. Distances between two dots in X, Y, and Z coordinates were measured in both the designed and fabricated frameworks. Marginal gaps between the framework and the abutments were also evaluated by impression replica method. RESULTS. In terms of distance measurement, significant differences were found between three- and four-unit frameworks, as well as between two- and four-unit frameworks prepared by milling technique (P<.05). Significant differences were also noted between two- and three-unit frameworks, as well as between two- and four-unit frameworks prepared by cast technique (P<.05). The milling technique presented smaller differences than the SLM technique, and the SLM technique showed smaller differences than the cast technique at any unit prostheses (P<.05). Evaluation with the impression replica method indicated significant differences among the span lengths for any fabrication method (P<.05), as well as among the fabrication methods at any unit prostheses (P<.05). CONCLUSION. The adaptation of implant-supported cobalt chromium frameworks was affected by the span length and fabrication method.

• 한국안전학회지
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• 제34권5호
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• pp.167-174
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• 2019

Compared to a single nuclear power plant (NPP) risk, the commonalities existing in the multiple NPPs attribute the characteristics of the multi-unit risk. If there is no commonality among the multiple NPPs, there will be no dependency among the risks of multiple NPPs. Therefore, understanding the commonality causing multi-unit events is essential to assessing the multi-unit risk, and identifying the characteristics of the multi-unit risk is necessary not only to select the scope and method for the multi-unit risk assessment, but also to analyze the data of the multi-unit events. In order to develop Korea-specific multi-unit risk assessment technology, we analyze the multi-unit commonalities included in the operational experiences of domestic NPPs. We identified 58 cases of multi-unit events through detailed review of domestic nuclear power plant event reports over the past 10 years, and the multi-unit events were classified into six commonalities to identify Korea-specific characteristics of multi-unit events. The identified characteristics can be used to understand and manage domestic multi-unit risks. It can also be used as a basis for modeling multi-unit events for multi-unit risk assessment.