• 한국컴퓨터정보학회논문지
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• 제12권6호
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• pp.193-200
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• 2007

기존의 바코드(Bar code) 시스템에 비하여 RFID(Radio Frequency Identification) 시스템은 저장능력이 뛰어나고 사물에 비접촉성을 갖는 장점이 있다. 그러나 RF(Radio Frequency) 신호를 이용하여 통신을 하기 때문에 전송되는 정보를 누구나 손쉽게 수신할 수 있어 시스템 보안과 개인의 프라이버시를 침해하는 문제점을 갖고 있다. 본 논문에서는 도청, 재전송, 스푸핑(Spoofing) 그리고 위치추적과 같은 공격에 안전하며 리더(Reader)와 태그(Tag) 간에 상호 인증을 효율적으로 할 수 있는 RFID 시스템을 제안한다. 제안한 시스템은 앞으로 유비쿼터스(Ubiquitous) 환경에서 다양한 분야에 활용될 수 있을 것이다.

• Journal of information and communication convergence engineering
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• 제7권2호
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• pp.164-169
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• 2009

An RFID system consists of radio frequency tags attached to objects that need to be identified and one or more electromagnetic readers. Unlike the traditional bar code system, the great benefit of RFID technology is that it allows information to be read without requiring contact between the tag and the reader. For this contact-less feature, RFID technology in the near future will become an attractive alternative to bar code in many application fields. In almost all the 13.56MHz RFID systems, FSA (Framed Slot ALOHA) algorithm is used for identifying multiple tags in the reader's identification range. In FSA algorithm, the tag identification time and system efficiency depend mainly on the number of tags and frame size. In this paper, we propose a tag number estimation scheme and a dynamic frame size allocation scheme based on the estimated number of tags.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.934-938
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• 2003

Flow analyses using FLUENT 5.4 code were performed to validate the application of the local bidirectional flow tube in case of water and air flow. In this study, sensitivity studies have been performed to optimize the design features of the bi-directional flow tube which can be applied for the various experimental conditions. 2-dimensional axisymmetric steady state flow analyses have been performed. By calculating the differential pressure at both the front and the rear hole of the flow tube, K values were evaluated. The K values show good linearity regardless of the tube sizes and the Re numbers in both water and air flow. And system pressure and water subcooling didn’'t affect the K values. Under the elevated pressure of 80bar with 80K water subcooling, the K value indicates a similar trend with the case of 2bar with 80K water subcooling.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.200-201
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• 2017

Generally, a lot of reinforcements are used in nuclear power plant concrete structures, and it may cause several potential problems when concrete is poured. Because of the congestion caused by hooked bars, embedded materials, and other reinforcements, it is too difficult to pour concrete into structural member joint area. The purpose of this study is to change ACI 349 Code for using the large-size(57mm) and high-strength(Gr.80) headed deformed bars instead of standard hooked bars in nuclear power plant concrete structures in order to solve the congestion problems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.61-63
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• 1987

In this paper, we develope a system which can perform signal processing for bar-code laser scanner. This system is composed of optical detector and preprocessor. The former detects the diffused light and converts it into TTL lebel output. The latter discriminator valid data from various raw data and transmits data to micro-processor. The preprocessor consists of edge transition detector, latch signal generator, module counter, register array, adder array, and buffer memory control circuit etc..

• 한국융합학회논문지
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• 제4권4호
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• pp.21-29
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• 2013

2차원 QR Code는 1차원 바코드의 용량, 크기, 방향에 대한 한계를 개선하였으며, 방대한량의 데이터를 압축하여 저장할 수 있는 능력을 갖추고 많은 응용분야에서 사용되고 있다. 최근에는 QR Code를 인식할 수 있는 스마트 폰의 도입과 사용의 증대로 QR Code의 도입이 급속도로 확산되었다. 하지만 다양한 정보를 저장할 수 있는 QR Code의 디코딩 기술에 대한 구체적인 문서화가 없는 상태이다. 따라서 본 논문에서는 QR code의 인코딩에 따른 디코딩 과정에 대해 구체적인 처리 절차와 알고리즘을 제시하고 예를 통해 디코딩 과정을 상세히 이해시키는데 연구목적이 있다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.683-688
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• 2007

Surface heat treatment of SM45C round bar by diode laser was simulated to find it's condition by using commercial finite element code MARC. Due to axisymmetric geometry, a quarter of model for SM45C round bar was considered and user subroutines were applied to boundary condition for the heat transfer. Material properties such as conductivity, specific heat and mass density were given as a function of temperature. Rotation speed of round bar and feed rate of beam were considered to design heat source model. Shape parameter values of heat source were determined by beam profile. As results, Three dimensional heat source model for diode laser beam conditions of surface hardening has been designed by the comparison between the finite element analysis results and experimental data on SM45C round bar. Diode laser surface hardening for SM45C round bar was successfully simulated and it should be useful to determine optimal heat treatment condition.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.177-180
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• 2008

최근에 철근콘크리트 구조물에서 철근의 부식문제를 해결하기 위하여 FRP bar를 철근의 대체제로 사용하려는 연구가 활발히 진행되고 있다. FRP bar는 비부식성 뿐만 아니라 철근에 비하여 자중이 작으면서도 고강도를 갖는 특성을 갖고 있다. 따라서 FRP bar가 경량골재콘크리트와 함께 사용된다면 해양에 부유되는 구조물등에서 우수한 특성을 발휘할 수 있을 것으로 예상된다. 그러나 현재까지 경량콘크리트에 FRP bar를 휨보강근으로 사용하는 구조체에 대한 연구는 거의 전무한 실정이다. 본 연구에서는 GFRP bar 경량콘크리트보에 대하여 콘크리트의 전단력 기여분을 조사하기 위하여 콘크리트 압축강도와 휨보강근비를 변수로 하는 일련의 실험을 행하였으며 이 결과를 분석하였다. 연구결과, 선행 연구에서 제안된 식에 0.75배를 곱하여 구한 콘크리트의 전단력은 실험결과와 잘 일치하였으며, ACI 440.1R-06에서 제시한 식에 의한 결과보다 더 우수한 값을 주는 것으로 나타났다.

• 한국인쇄학회지
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• 제29권3호
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• pp.31-40
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• 2011

Using of QR(Quick Response) code is dramatically extended to various marketing area; not only substitute of bar code but also new tool of PR and marketing. This research attempts to analyze brand communication effect using QR code printed on product package especially in snack product category. Findings are 1) communication effect are different according to the type of book-trailers; 2) cinematic production and animation are the most effective type of book-trailers; 3) for memory and confirmation(sharing), a)stills and straplines, Analysis result of hypothesis I showed that characters of QR code influence on brand attitude. Among dependent variables, only reliability is significant. That means reliability of company and brand using QR code influence on brand attitude. The higher reliability of QR code, the better brand attitude of the brand. Analysis result of hypothesis II found that only reliability is significant on purchasing intention. Reliability of company and product using QR code influences on purchasing intention. The higher reliability of QR code, the higher possibility of purchasing products. Therefore, company can enhance reliability of both company and its products by using QR code. Using QR code will bring high reliability and high brand attitude and purchasing intention.

• Architectural research
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• 제19권4호
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• pp.117-124
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• 2017

In this research, we carried out finite element analysis depends on the variations such as the strength of the main bar, concrete, shear-span ratio(a/d) and existence of shear reinforcing bar. Throughout the results of FEM analysis, we were able to figure out how each variation can effect on shear performance. As the strength of concrete increased, the maximum shear force enhancement effect of each specimen was evaluated. As a result, the shear strengthening effect was 51~97% for shear reinforced specimens, and 26~44% for non-shear reinforced specimens. As the yield strength of reinforcing bars increases, the shear reinforcement effect of the specimen the specimens without shear reinforcement were 3%~6% higher than those with shear reinforcement. Theoretical and analytical values were compared using the design equations obtained from the CEB code. Theoretical and analytical values were compared using the design equations obtained from the CEB code. As a result, the error rate was the highest at 3.64 in the S1.0-C0 series and the lowest at 1.46 in the S1.7-C1 series. Therefore, the design equation of the CEB code is estimated to underestimate the actual shear strength of deep beams that are not subjected to shear reinforcement.