• 한국CDE학회논문집
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• 제5권2호
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• pp.168-174
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• 2000

A biarc is a curve connecting two circular arcs with the constraints of tangent continuity so that it can represent the free form currie approximately connecting several biarcs with the tangent continuity. Since a biarc consists of circular arcs, the offset curve of the curve represented by biarcs can be easily obtained. Besides. if the tool path is represented by biarcs, the efficiency of machining is improved and the amount of data is decreased. When approximating a curve with biarcs, the location of the point where two circular arcs meet each other plays an important part in determining the shape of a biarc. In this thesis, the optimum point where two circular arcs meet is calculated using the tangent information of the curve to approximate so that it takes less calculation time to approximate due to the decrease of the number of iterations.

• 한국학교수학회논문집
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• 제3권2호
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• pp.155-164
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• 2000

The future society will demand that enables one to solve in many fields by connecting various informations in many fields and then creating his own information. In the coming society, creativeness will be regarded much important. This ability can be developed with materials through group activities experimental class in math classes. This classes using these materials are not teacher-oriented, explanatory classes but student-oriented ones. They offer students opportunities to think by themselves and expand their potential abilities. They are suitable for rising and keeping student's interests. Therefore experimental classes through group activities enable students to think mathematically and make them recognize the importance of mathematical approach by letting them work connecting other subjects or things in real life. They can develop not only expressive, communicative ability and cooperative spirit, but also the ability to transcend the class itself and then reorganize facts in new insights. Besides, math classes with experiments can arouse student's curiosity familiarizing them with mathematics. Moreover, they can expand student's originative and problem-solving abilities.

• 한국국방경영분석학회지
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• 제29권1호
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• pp.43-56
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• 2003

This paper is intended to investigate the Build-up Method of SCM(Supply Chain Management) Connection applying EC Standard. SCM helps companies plan and supply to meet customer demand. SCM is the only solution available today that enables an organization to strategize, plan and execute a company's buy, make, move, store, fulfill and service business processes across multiple enterprises for total profitability. The research of modern scientists has thrown new light on the subject. However, the study of SCM for EC Standard has been strangely neglected by critics. Consequently, existing SCM systems, which require to introduce the functions of EC, need to be changed. Summarizations of the main points that have been analyzed in this paper are as follows:. the sharing information for connection and the Rosetta-net standard of the existing SCM system(Order management module(PIP 3A4) of the Rosetta-net specifications for connection by the Rosetta-net). Finally, it shows the process of the gateway for connecting among the existing SCM systems.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.207-211
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• 2015

In this paper, 2 kinds of models about bike frame are simulated with static structural analysis. A bike frame with diamond type is compared with another model that Down tube is eliminated from original diamond frame. About both types of models, Property of a material and conditions of restriction & load are the same. This study shows reinforcement effects of a partial frame by adding down tube and impacts generated by applying a load at the frame such as weak points & high stress parts as well as expected deformation. The structural result of this study indicates that the equivalent stress or total deformation decreases by 57.1% or 36.4%, respectively. Also stress concentration sites are leg connecting parts, front/rear wheels fixed region and Max deformation is generated from Seat tube. In conclusion, A Down tube is highly efficient as reinforcement than frame without non down tube. Furthermore, The safety rises in case of reducing top tube thickness and increasing a reinforcement at leg connecting parts or concentration regions.

• 전자통신동향분석
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• 제33권2호
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• pp.1-9
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• 2018

In the past, the Internet connected people together; recently, however it has been extended to the Internet of Things (IoT), allowing all things in the physical world to be connected. We call a new society in which everything is connected through IoT a 'hyper-connected society'. IoT for a hyper-connected society is more than just connecting things to the Internet, it is an infrastructure providing intelligent services without human intervention by connecting things to the Internet using sensors and communication functions, collecting data from connected things, and analyzing and predicting information. Therefore, IoT is a convergence technology that includes not only sensors and communication networks but also big data and AI. This paper examines the short history of IoT, reviews its current trends, and finally, discusses its future direction.

• Communications for Statistical Applications and Methods
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• 제27권2호
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• pp.211-224
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• 2020

Sensitivity and specificity are popular measures described by the receiver operating characteristic (ROC) curve. There are also two other measures such as the positive predictive value (PPV) and negative predictive value (NPV); however, the PPV and NPV cannot be represented by the ROC curve. Based on the total operating characteristic (TOC) curve suggested by Pontius and Si (International Journal of Geographical Information Science, 97, 570-583, 2014), explanatory methods are proposed to geometrically describe the PPV and NPV by the TOC curve. It is found that the PPV can be regarded as the slope of the right-angled triangle connecting the origin to a certain point on the TOC curve, while 1 - NPV can be represented as the slope of the right-angled triangle connecting a certain point to the top right corner of the TOC curve. When the neutral zone exists, the PPV and 1-NPV can be described as the slopes of two other right-angled triangles of the TOC curve. Therefore, both the PPV and NPV can be estimated using the TOC curve, whether or not the neutral zone is present.

• 정보보호학회논문지
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• 제28권2호
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• pp.513-528
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• 2018

주거 환경에 IoT 기술을 융합한 스마트홈 환경에서 스마트홈 허브는 다양한 IoT 기기들을 네트워크로 연결하여 사용자에게 편의 기능을 제공한다. 스마트홈 허브는 IoT 기기들을 연결하여 활용하는 과정에서 다양한 데이터가 오고가는 통로의 역할을 하는데, 이 데이터에는 사용자의 생활환경과 밀접한 관련이 있어 개인정보로써 악용될 수 있다. 이러한 개인정보의 악용으로 사용자의 신원 노출 등 피해가 발생할 수 있다. 따라서 본 논문은 스마트홈 허브에 대해 기존에 국내에서 사용하지 않았던 개인정보보호 측면의 위협 모델링 기법인 LINDDUN을 사용하여 위협을 분석하였다. 분석한 위협과 대응하는 보안요구사항을 국제표준인 common criteria를 사용하여 스마트홈 허브에 대한 평가 기준을 제시한다.

• 대한전자공학회논문지SD
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• 제38권11호
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• pp.804-809
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• 2001

본 논문에서는 광 WDM 멀티홉 네트워크에서 필요한 파장 채널 수를 줄이기 위하여 격행 연결 이중층 셔플넷 방식을 이용한 효과적인 채널 공유 방식과 이를 위한 라우팅 알고리즘을 제안한다. 채널 공유 방법은 2P개의 노드들이 하나의 채널을 공유하게 하는 방법으로써 전체적으로 필요한 파장 수가 기존의 방법에 비하여 줄어들게 된다. 각 열에 있는 노드는 두 개씩 짝을 이루게 하여 각각의 쌍의 번호를 p-진수로 계산하고, 각 쌍의 위에 위치한 노드에는 2-진수의 0을 첨가하고 아래에 위치한 노드에는 2-진수의 1을 첨가하여 각 노드에 대한 주소를 결정한다. 이와 같이 정해진 주소를 이용하여 효과적으로 패킷을 중계하도록 알고리즘을 제안하고 (4, 2) 토폴로지에서의 경로설정 방법을 예를 들어 설명한다.

• 한국통신학회논문지
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• 제32권7B호
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• pp.431-437
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• 2007

웹 프록시 캐슁은 원하는 데이터를 접근하기 위한 지연시간과 요구하는 통신망의 대역폭을 줄이는데 효과적인 방법을 제공한다. 특히 프리픽스 캐슁은 비디오 WAN에서 비디오 전송을 위한 대안으로서 간주되는데 이는 비디오 데이터는 그 양이 너무 커서 데이터 전체를 캐쉬에 저장하는데 문제를 야기시키기 때문이다. 또한 최근의 많은 연구결과에 의하면 사용자가 인식하는 지연시간은 데이터를 전송하는 전송시간에 의해 영향을 받는 것이 아니라 TCP 연결설정 시간과 같이 데이터 전송단계를 선행하는 설정과정에 의해 많은 영향을 받는다는 것이다. 본 논문은 프록시 캐슁에서 사용되는 TCP pre-connecting 기법을 제안하며 이 기법이 TCP splicing에서 효율적으로 사용될 수 있다는 것을 보인다. 아울러 제시된 수치적인 모델은 start-up 지연시간을 줄일 수 있음을 보인다. 제안된 기법은 어떠한 프로토콜 수정이나 다른 엔티티와의 동작을 요구하지 않는다.

• 소성∙가공
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• 제16권1호
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• pp.25-30
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• 2007

The present study covers an integrated simulation method to evaluate optical performance of an aspheric plastic lens by connecting a finite element (FE) analysis of injection molding with a ray tracing simulation. Traditional ray tracing methods have based on the assumption that the optical properties of a lens are homogeneous throughout the entire volume. This assumption is to a certain extent unrealistic for injection-molded plastic lenses because material properties vary at every point due to the injection molding effects. To take into account the effects of the inhomogeneous optical properties of the molded lens, a new.ay tracing scheme is proposed in conjunction with a FE analysis of the injection molding. A numerical scheme is developed to calculate ray paths on every element layer with more realistic information of the refractive indices which can be obtained through the FE analysis. This information is then used to calculate the ray paths based on the FE mesh of which nodal points have unique index values. The proposed tracing scheme is implemented on the tracing of an aspheric lens, and its validity is ascertained through experimental verification.