• Advances in robotics research
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• 제2권1호
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• pp.33-44
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• 2018

This paper presents a novel feature detection algorithm called depth-hybrid speeded-up robust features (DH-SURF) augmented by depth information in the speeded-up robust features (SURF) algorithm. In the keypoint detection part of classical SURF, the standard deviation of the Gaussian kernel is varied for its scale-invariance property, resulting in increased computational complexity. We propose a keypoint detection method with less variation of the standard deviation by using depth data from a red-green-blue depth (RGB-D) sensor. Our approach maintains a scale-invariance property while reducing computation time. An RGB-D simultaneous localization and mapping (SLAM) system uses a feature extraction method and depth data concurrently; thus, the system is well-suited for showing the performance of the DH-SURF method. DH-SURF was implemented on a central processing unit (CPU) and a graphics processing unit (GPU), respectively, and was validated through the real-time RGB-D SLAM.

• Journal of information and communication convergence engineering
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• 제15권2호
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• pp.97-103
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• 2017

Implementation of faster pairing calculation is the basis of efficient pairing-based cryptographic protocol implementation. Generally, pairing is a costly operation carried out over the extension field of degree $k{\geq}12$. But the twist property of the pairing friendly curve allows us to calculate pairing over the sub-field twisted curve, where the extension degree becomes k/d and twist degree d = 2, 3, 4, 6. The calculation cost is reduced substantially by twisting but it makes the discrete logarithm problem easier if the curve parameters are not carefully chosen. Therefore, this paper considers the most recent parameters setting presented by Barbulescu and Duquesne [1] for pairing-based cryptography; that are secure enough for 128-bit security level; to explicitly show the quartic twist (d = 4) and sextic twist (d = 6) mapping between the isomorphic rational point groups for KSS (Kachisa-Schaefer-Scott) curve of embedding degree k = 16 and k = 18, receptively. This paper also evaluates the performance enhancement of the obtained twisted mapping by comparing the elliptic curve scalar multiplications.

• KIEE International Transaction on Systems and Control
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• 제2D권2호
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• pp.92-96
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• 2002

This paper is concerned with properties of a Lyapunov functional of state delay systems. It is shown that if a state delay system has a pure imaginary pole for some state delay, then no Lyapunov functional satisfying a Lyapunov condition exists periodically with respect to change of the state delay. This periodic property is unique in state delay systems and has been well known in the frequency domain stability conditions. However, in the time domain stability conditions using a Lyapunov functional, the periodic property is not known explicitly.

• Journal of Korean Vacuum Science & Technology
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• 제5권2호
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• pp.52-55
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• 2001

We report best dielectric function of ZnS by spectroscopic ellipsometry in the 3.7 - 6.0 eV photon energy range at room temperature. Using proper wet chemical etching procedure, natural overlayer was removed to obtain the pure dielectric function of ZnS, which had a higher <$\xi$$_2$> value at the El band gap peak than that previously reported. We also determined the dielectric property of the natural overlayer on ZnS by following the evolution of <$\xi$$_2$> with chemical etching. We found that the optical property of the overlayer was well described by amorphous semiconductor model.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1998년도 춘계학술대회 및 발표대회 강연 및 발표논문 초록집
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• pp.6-6
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• 1998

In 1957, the first magnetic disk drive compatible with a movable head was introduced as an external file memory device for computer system. Since then, magnetic disks have been improved by increasing the recording density, which has brought about the development of a high performance thin film magnetic head. The thin film magnetic head has a magnetic circuit on a ceramic substrate using IC technology. The physical property of the substrate material is very important because it influences the tribology of head/disk interface and also manufacturing process of the head. $Al_{2}O_{3}$-TiC ceramics, so called ALTIC, is known to be one of the best substrate materials which satisfies this property requirement. Even though the head is not in direct contact with the disk, frequent instantaneous contacts are unavoidable due to its high rotating speed and the close gap between them. This may cause damage in the magnetic recording media and, thus, it is very important that the magnetic head has a good wear resistance. $Al_{2}O_{3}$-TiC ceramics has an excellent tribological property in head/disk interface. Manufacturing process of thin film head is similar to that of IC, which requires extremely smooth and flat surface of the substrate. The substrate must be readily sliced into the heads without chipping. $Al_{2}O_{3}$-TiC ceramics has excellent machineability and mechanical properties. $Al_{2}O_{3}$-TiC ceramics was first developed at Nippon Tungsten Co. as cutting tool materials in 1968, which was further developed to be used as the substrate materials for thin film head in collaboration with Sumitomo Special Metals Co., Ltd. in 1981. Today, we supply more than 60% of the substrates for thin film head market in the world. In this paper, we would like to present the sintering process of $Al_{2}O_{3}$-TiC ceramics and its property in detail.

• 대한공업교육학회지
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• 제45권2호
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• pp.108-130
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• 2020

이 연구는 4차 산업혁명 시대의 도래에 따른 급속한 과학 기술의 변화, 다양한 사회와 복잡한 경제에 대응하기 위해서는 지식재산교육이 무엇보다도 필요하다. 이에 지식재산 분야와 분야별 필요 역량을 도출하고 타당성을 검증받았다. 연구방법은 문헌고찰과 전문가 대상으로 2회 델파이 조사를 실시하였고, 연구 결과에 따른 연구 결론은 다음과 같다. 첫째, 4차 산업혁명 시대에 필요한 지식재산 분야는 문헌고찰과 델파이 조사를 통해 IP-R&D 컨설팅, IP 정보조사분석, IP 권리화, IP 전략 기획, IP 거래, IP 금융, IP 가치 평가, IP 관리, 글로벌 IP 관리, IP 사업화, IP 분쟁 11개로 분류하였고 타당성을 검증하였다. 둘째, 지식재산 분야별로 도출된 필요 역량은 타당도한 것으로 분석되었다. 셋째, 지식재산 분야에 따른 분야별 인력 양성은 대학 또는 대학원에서 이루어지는 것이 대체로 적절하다. 또한 기업 등 산업체와 공공기관 등의 상시 직무교육은 분야와 구분 없이 필요하다고 판단된다.

• 정보화연구
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• 제11권4호
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• pp.495-504
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• 2014

본 논문은 2D3D 영상데이터 변환 기술에 관한 특허를 조사, 분석하여 핵심 기술 개발 방향 및 지재권 획득 전략 수립을 제시한 것이다. 특허 동향을 살펴본 결과 2D to 3D 영상데이터 변환 기술은 계속 성장중인 단계라 할 수 있으며, 향후 발전 가능성이 많은 분야라 할 수 있다. 특허 동향 연구를 통해 전략적 특허맵을 형성한다면, 2D to 3D 영상데이터 변환 시장경쟁에서 앞서 나갈 수 있을 것이다.

• 대한수학회보
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• 제21권2호
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• pp.91-95
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• 1984

Let D$^{p}$ be the space of distributions of $L^{p}$-growth and S the space of tempered destributions in $R^{n}$: D$^{p}$, 1.leq.P.leq..inf., is the dual of the space $D^{p}$ which we discribe later. We denote by O$_{c}$(S:S') the space of convolution operators in S. In [8] S. Sznajder and Z. Zielezny proved the following necessary conditions for convolution operators in O$_{c}$(S:S) to be solvable in S.

• Journal of applied mathematics & informatics
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• 제20권1_2호
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• pp.541-548
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• 2006

We find a graded Artinian level O-sequence of the form $H\;:\;h_0\;h_1\;\cdots\;h_{d-1}\;h_d\cdots$ $^{(d+1-1_)-st}h_d$ < $h_{d+s}$ not having the Weak-Lefschetz property. We also introduce several algorithms for construction of some examples of non-unimodal level O-sequences using a computer program called CoCoA.

• 대한수학회보
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• 제59권2호
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• pp.453-468
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• 2022

In this article, we define a module M to be G^z-extending if and only if for each z-closed submodule X of M there exists a direct summand D of M such that X ∩ D is essential in both X and D. We investigate structural properties of G^z-extending modules and locate the implications between the other extending properties. We deal with decomposition theory as well as ring and module extensions for G^z-extending modules. We obtain that if a ring is right G^z-extending, then so is its essential overring. Also it is shown that the G^z-extending property is inherited by its rational hull. Furthermore it is provided some applications including matrix rings over a right G^z-extending ring.