• Journal of the Korean Society of Radiology
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• v.15 no.7
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• pp.965-973
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• 2021

Since radiation therapy is irradiated with high-energy X-rays in a variety of at least 20 Gy to 80 Gy, a high dose is administered to the local area where the tumor is located, and various side effects of some normal tissues are expected. Currently, in clinical practice, lead, a representative material, is used as an effort to shield normal tissues, but lead is classified as a heavy metal harmful to the human body, and a large amount of skin contact can cause poisoning. Therefore, this study intends to manufacture a measurement sheet that can compensate for the limitations of lead using the materials Tungsten, Brass, and Copper of the 3D printer of the FDM (Fused Deposition Modeling) method and to investigate the penetration performance. Tungsten mixed filament transmission measurement sheet size was 70 × 70 mm and thickness 1, 2, 4 mm using a 3D printer, and a linear accelerator (TrueBeam STx, S/N: 1187) was measured by irradiating 100 MU at SSD 100 cm and 5 cm in water using a water phantom, an ion chamber (FC-65G), and an elcetrometer (PTW UNIDOSE), and the permeability was evaluated. As a result of increasing the measurement sheet of each material by 1 mm, in the case of Tungsten sheet at 3.8 to 3.9 cm in 6 MV, the thickness of the lead shielding body was thinner than 6.5 cm, and in case of Tungsten sheet at 4.5 to 4.6 cm in 15 MV. The sheet was thinner than the existing lead shielding body thickness of 7 cm, and equivalent performance was confirmed. Through this study, the transmittance measurement sheet produced using Tungsten alloy filaments confirmed the possibility of transmission shielding in the high energy region. It has been confirmed that the usability as a substitute is also excellent. It is thought that it can be provided as basic data for the production of shielding agents with 3D printing technology in the future.

• 한국정보교육학회:학술대회논문집
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• 2021.08a
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• pp.385-391
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• 2021

In this paper, a case of deep learning artificial neural network education was studied for artificial intelligence literacy education for preservice teachers and incumbent teachers. In addition, through the proposed educational case, we tried to explore the contents of artificial neural network principle education that elementary, middle and high school students can experience. To this end, first, an example of training on the principle of operation of an artificial neural network that recognizes two types of images is presented. And as an artificial neural network extension application education case, an artificial neural network education case for recognizing three types of images was presented. The number of output layers was changed according to the number of images to be recognized by the artificial neural network, and the cases implemented in a spreadsheet were divided and explained. In addition, in order to experience the operation results of the artificial neural network, we presented the educational contents to directly write the learning data necessary for the artificial neural network of the supervised learning method. In this paper, the implementation of the artificial neural network and the recognition test results are visually presented using a spreadsheet.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.5
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• pp.79-86
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• 2010

This study was performed to evaluate the flexural behavior of Hybrid fiber sheet (HFC) and Hybrid fiber bar (HFB) strengthened reinforced concrete (RC) beams. According to test results, Hybrid fiber reinforcement strengthened RC beams showed approximately 60 to 200% higher reinforcing effects than that of un-reinforced specimens. In addition, the reinforced beams showed the ideal failure pattern, which is failed presenting the ductile behavior after yielding of the reinforcing bar. More specifically, in the case of HFB reinforced RC beams, the difference with puttying method was not apparent since HFB beams reinforced using the injection of epoxy and bonding of putty showed the similar failure patterns.

• Electronics and Telecommunications Trends
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• v.9 no.2
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• pp.23-35
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• 1994

본 고에서는 체신부의 종합정보서비스 전산망에서 운영될 수 있는 문서유통시스템을 설계하였다. 체신부 문서유통시스템은 체신부의 우체국(주사국, 감독우체국, 체신청, 본부)에서 처리되는 각종 정기보고 문서와 지시문서, 공용문서, 서식관리등을 처리하는 시스템으로, 워드프로세서, 스프레드시트 등의 PC 응용과 전자우편시스템, 관계형 데이터베이스 시스템이 접목되도록 설계되었다. 따라서 본 문서유통시스템 S/W는 데이터베이스 관리블록, 전자우편 블록, 집계 블록, 자료관리 블록, 사용자 인터페이스 블록과 시스템 소프트웨어 및 유틸리티 등으로 구성된다. 체신부의 종합정보서비스전산망은 주컴퓨터인 TICOM-II, 서버로서 체신청과 감독우체국별로 설치된 PC486, 주사국 및 감독국에 설치된 업무용 PC들로 이루어져 있다. 본 시스템의 처리방식은 이러한 컴퓨터 구조에서 효율적으로 처리될 수 있도록 문서생성은 PC에서, 문서유통은 각 서버에서, 데이터베이스 관리는 주컴퓨터에서 수행되도록 지역분산처리 방식으로 설계되었다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.307-312
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• 2017

In this study, we proposed a method to generate a maintenance documents for railway track through Construction Operations Building information exchange(COBie) which is a subset of Industry Foundation Classes(IFC), a data model for Building Information Modeling(BIM). In order to define the items necessary for railway track maintenance document generation, we analyzed the guideline of maintenance and management to track by the Ministry of Land, Infrastructure and Transport(MLTM), and defined the way to refer to the information items in the COBie spreadsheet. The additional properties not supported in IFC, were created for generation of an Information model that reflecting maintenance information items of railway track by applying user-defined property set within the IFC framework. An IFC-based Information model reflecting the user-defined property was implemented through BIM software, and rail track maintenance information items were transferred to COBie spreadsheet according to the defined approach. It is tested that the information can be transferred from the IFC-based as-built model to the COBie spreadsheet, which can be used to generate the necessary documents for railway facility maintenance work.

• Journal of Advanced Navigation Technology
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• v.18 no.4
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• pp.319-324
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• 2014

Line operation safety audit (LOSA) is the proactive data collection system to capture the accident and serious incident caused by flight crew and is the safety management program for collecting threat error management (TEM) and crew resource management (CRM) during normal operations. The typically LOSA is written by hand, manages and archives the LOSA Observation Worksheet. But, this method is not easy to archive and ensure confidentiality of the LOSA worksheets. As we implemented the K-LOSA of the web-document type instead of the existing LOSA archive method and change the TEM category code. we yields to archive the efficient data management and confidentiality. In this paper, we introduce the LOSA and to configure the K-LOSA program.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1066-1069
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• 2003

요즘, LCD TV 가 등장하면서 LCD 백라이트로써 LCD TV 에 적용하기 위해서는 무엇보다도 휘도특성의 개선이 요구되고 있다. TV 대응 LCD Panel 은 Monitor 대응 제품에 비해서 일반적으로 해상도가 낮으므로, 투과율면에서 장점은 있으나, 현재의 백라이트 구조로는 만족할만한 성능을 낼 수 없는 상황이다. 그러므로 고휘도 백라이트를 위해서 EEFL(External Electrode Fluorescent Lamp) 혹은 CCFL(Cold Cathode Fluorescent Lamp) 의 복수 사용을 전제로 한 직하방식에 대한 개발 검토가 활발히 이루어지고 있다. 직하방식에 의한 고휘도화는 램프수는 증가되지만 프리즘시트를 사용하지 않아서 가격 경쟁력이 있다. 따라서 본 연구에서는 EEFL 16등을 이용하여 17인치 직하형 백라이트를 제작하여 기구적, 전기적, 광학적 특성을 분석하였으며, 그 결과 11,700 nit 의 휘도를 달성하여 TV 대응 수준을 확보하였다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.15-21
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• 2015

The glass used for Mobile Camera Window is required to have high strength. Cell type manufacturing by means of CNC is widely used for camera window. Individual loading and unloading is needed for each process, such as painting and PVD, in cell type manufacturing. The purpose of this study is to search the enhanced manufacturing process with sheet type throughout bulk unit production in painting and PVD. This study includes sheet type manufacturing processes such as laser cutting, wet etching, 2nd tempering, printing, and AF/AR coating.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.01a
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• pp.273-274
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• 2017

대한민국 20대 총선, 영국의 유럽연합 탈퇴인 브렉시트, 트럼프와 힐러리의 대결인 미국 대선, 이 셋의 공통점은 언론의 예측과 다른 투표 결과가 나왔다는 점이다. 이러한 일련의 사건들로 인해, 각종 언론사에서 실시하고 있는 표본조사의 신뢰도에 대한 근본적 재검토의 필요성이 제기되고 있는 실정이다. 본 논문에서는 선거 후보자 지지율을 효율적이며 효과적으로 분석하기 위하여 SNS 감정분석을 제안한다. SNS 감정분석은 기존의 표본을 구하고 분석하는 방식보다 더 빠르게 표본 수집 및 분석이 가능하다. 또한 R프로그램과 구글을 이용하여 처리하기 때문에 기존 방식에 비하여 매우 저렴하다. 현재 언론사의 예측이 빗나가고 있는 시점에서 SNS 감정분석이 훌륭한 대안이 될 수 있을 것이다. 본 연구에서의 트래픽*감정분석 점수를 보았을 때, SNS 감정분석이 여론을 더 정확히 반영한다는 것을 증명한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.2
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• pp.122-136
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• 1986

In this paper, the new modulation system, the digital phase-frequency hybrid modulation system is proposed for mobile radio communications. The error rate and the outage equation of PFSK(Phase-Frequency Shift Keying) signal transmitted through the fading channel has been derived considiering deversity techniques. The error rate and the outgae rate performances of PFSK system have been evaluated and shown in figures in terms of carrier-to-noise power ratio(CNR), fading figure, numbers of diversity branches, correlation coefficient among the diversity branches. And the performance of PFSK system is superior to that of QDPSK system. And by using diversity techniques, system performances can be improved 13dB above in CNR.