• 대한수학회보
• /
• 제33권4호
• /
• pp.603-611
• /
• 1996

Let consider the following problem: find an element u(t) in a Banach space U from the equation $$ x'(t) = Ax(t) + f(t,x(t)) + \Phi_0 u(t), 0 \leq t \leq T $$ with initial and terminal conditions $$ x(0) = 0, x(T) = \phi $$ in a Banach space X where $\phi \in D(A)$. This problem is a kind of control engineering inverse problem and contains nonlinear term, so that it is difficult and interesting. Thee proof main result in this paper is based on the Fredholm property of [1] in section 3. Similar considerations of linear system have been dealt with in many references. Among these literatures, Suzuki[5] introduced this problem for heat equation with unknown spatially-varing conductivity. Nakagiri and Yamamoto[2] considered the identifiability problem, which A is a unknown operator to be identified, where the system is described by a linear retarded functional differential equation. We can also apply to determining the magnitude of the control set for approximate controllability if X is a reflexive space, i.e., we can consider whether a dense subset of X is covered by reachable set in section 4.

• 대한수학회논문집
• /
• 제19권2호
• /
• pp.321-328
• /
• 2004

In this paper, we will prove the following: Let D be a nonempty of a normed linear space X and T : D -> X be a nonexpansive mapping. Let ${x_n}$ be a sequence in D and ${t_n}$, ${s_n}$ be real sequences such that (i) $0\;{\leq}\;t_n\;{\leq}\;t\;<\;1\;and\;{\sum_{n=1}}^{\infty}\;t_n\;=\;{\infty},\;(ii)\;(a)\;0\;{\leq}\;s_n\;{\leq}\;1,\;s_n\;->\;0\;as\;n\;->\;{\infty}\;and\;{\sum_{n=1}}^{\infty}\;t_ns_n\;<\;{\infty}\;or\;(b)\;s_n\;=\;s\;for\;all\;n\;{\geq}\;1\;and\;s\;{\in}\;[0,1),\;(iii)\;x_{n+1}\;=\;(1-t_n)x_n+t_nT(s_nTx_n+(1-s_n)x_n)\;for\;all\;n\;{\geq}\;1.$ Then, if the sequence {x_n} is bounded, then $lim_{n->\infty}\;$\mid$$\mid$x_n-Tx_n$\mid$$\mid$\;=\;0$. This result improves and complements a result of Deng [2]. Furthermore, we will show that certain conditions on D, X and T guarantee the weak and strong convergence of the Ishikawa iterative sequence to a fixed point of T.

• 한국의류산업학회지
• /
• 제6권6호
• /
• pp.749-755
• /
• 2004

This paper was conducted to compare the methods of women's basic pattern and the problems by analyzing the space between skin and clothing using 3D scanner and thereupon, proposed the solutions. The Bunka pattern of Japan Bunka Women's University(Bunka) and the Secoli pattern of Italy istituto carlo secoli(Secoli) were used. The subject who has nearly the same body size with N type of National anthropometric survey of Korea in 1997 was picked out. In the result of analyzing the space between skin and clothing of each pattern by 3D Scanner, there exist significant differences in the chest and bust parts. The Bunka has more space than the Secoli at bust part, especially between bust points. Because the Bunka has the bust dart which was made from only the bust girth, it couldn't reflect the difference of each human body. Whereas the Secoli has the bust dart which gave a consideration the difference between the bust girth and the chest girth, it has more even space between skin and clothing.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
• /
• pp.30.3-30.3
• /
• 2008

In this study, we investigate the magnetic latitude of phase reversal on the sudden commencement (SC)-associated preliminary impulse with 267 SC events using the ground magnetometer data of the IMAGE from 1997 to 2005. During SC event, geomagnetic fields are affected by various currents flowing in the magnetosphere and/or ionosphere. In particular, high-latitude geomagnetic field variations are significantly dominated by the change of SC-associated field aligned current (FAC). Until now, however, there are few studies to examine where the location of the FAC in the ionosphere is and what determines the location of the FAC. The location of the SC-associated FAC can be examined by using magnetometer data obtained from high-latitude stations distributed along the same magnetic meridian. The phase reversal locations are concentrated two regions, ~62 deg (L~4.5) and ~70 deg (L~8.5) in magnetic latitude. If FAC is a result of a mode conversion from fast mode to Alfven mode, then the FAC location could be determine by the duration time of the input energy. When we use the rise time, dT, as the input energy, there is no relationship between dT and the location where the first pulse of SC is reversed. We consider other factors such as local time and solar wind condition.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
• /
• pp.390-392
• /
• 2003

Video mosaicing techniques have been widely used in virtual reality environments. Especially in GIS field, video mosaics are becoming more and more common in representing urban environments. Such applications mainly use spherical or panoramic mosaics that are based on images taken from a rotating camera around its nodal point. The viewpoint, however, is limited to location within a small area. On the other hand, 2D-mosaics, which are based on images taken from a translating camera, can acquire data in wide area. The 2D-mosaics still have some problems : it can‘t be applied to images taken from a rotational camera in large angle. To compensate those problems , we proposed a novel method for creating video mosaics in 3D space. The proposed algorithm consists of 4 steps: feature -based optical flow detection, camera orientation, 2D-image projection, and image registration in 3D space. All of the processes are fully automatic and successfully implemented and tested with real images.

• 대한수학회보
• /
• 제20권1호
• /
• pp.15-25
• /
• 1983

The main purpose of the present paper is to generalize the results obtained by A. Hindmarsh in [7] to the holomorphic functions with non-negative real part defined on a complete circular domain D in certain class D in the complex euclidean space $C^{n}$. As described in .cint.2, D includes the bounded symmetric domains.s.

• 대한의용생체공학회:의공학회지
• /
• 제21권4호
• /
• pp.333-338
• /
• 2000

본 논문에서는 T1 강조영상, T2 강조 영상 그리고 PD의 영상의 특징을 상호 보완적으로 이용한 자동적인 영상 분할법을 제안한다. 제안한 분할 알고리듬은 3단계로 이루어지는데, 첫 단계에서는 PD 영상으로부터 대뇌 마스크를 획득한 후, T1과 T2, PD의 입력 영상에 대뇌 마스크를 씌워 각각의 대뇌 영상을 추출하고, 둘째 단계에서는 대뇌 내부 조직에 해당하는 두드러진 클러스터(outstanding cluster)를 3차원 클러스터들 중에서 선택한다. 3차원 클러스터는 최적스케일 영상(optimal scale image)으로 이루어지는 3차원 공간상에서 화소가 밀집된 봉우리들을 교집합해서 생성되는 클러스터로 결정한다. 최적스케일 영상은 각 2타원 히스토그램에 스케일 스페이스 필터링을 적용시키고 그래프(graph) 구조를 검색하여 2차원 히스토그램의 모양을 가장 잘 나타내는 봉우리(peak) 영상을 최적 스케일 영상으로 선택한다. 마지막 단계에서는 앞에서 찾은 두드러진 클러스터의 중심값을 FCM 알고리듬의 초기중심 값으로 두고, FCM 알고리듬을 이용하여 대뇌 영상을 분할한다. 제안한 분할 알고리듬은 정확한 클러스터의 중심값을 계산함으로 초기 값을 영향을 많이 받는 FCM 알고리듬의 단점을 보완하였고 다중 스펙트럼 영상의 특성을 조합하여 분할에 이용함으로 단일 스펙트럼 영상만을 이용하는 방법보다 향상된 결과를 얻을 수 있었다.

• 한국방재안전학회논문집
• /
• 제9권1호
• /
• pp.25-32
• /
• 2016

기술의 개발은 인류의 활동영역을 넓히고, 기존에 대응하지 못했던 재난 상황에의 대응을 가능케 한다. 한편, 인류의 우주개발 활동은 새로운 종류의 재난인 우주물체에 의한 위험을 인식하게 하였다. 지난 '13년 러시아 첼야빈스크에 추락하여 1천 5백여 명의 인명피해를 낸 소행성처럼 과거에는 혜성 등 자연우주물체만이 위험요소에 해당하였다면, 오늘날에는 '87년 구소련의 원자력 핵전지 탑재 위성 추락, '12년 러시아의 포보스-그룬트 위성 추락 등 인공우주물체의 추락마저도 인류가 적극적으로 대처해야 할 위험요인이 된 것이다. 이에 정부에서는 국가차원의 대비책을 마련하고자 '14년에 우주위험대비기본계획을 확정하여 우주위험 예 경보 및 감시 분석 능력 등에 대한 목표를 제시한 바 있다. 본 연구에서는 우주위험을 대비하기 위해 개발해야 하는 기술의 중요성 및 시급성을 도출하기 위하여 관련 전문가를 대상으로 AHP 설문조사를 실시하였으며, 이의 결과를 근거로 우주위험감시기술개발 추진을 위한 정책전략을 제시하고자 한다.

• 한국경영과학회:학술대회논문집
• /
• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
• /
• pp.564-567
• /
• 2004

The government has focused the national R&D investment on 6T areas - IT(Information Technology), BT(Bio Technology), NT(Nano Technology), ST(Space Technology), ET(Environment ${\cdot}$ Energy Technology), CT(Culture Technology). The paper summarizes patents and utility models in these areas which are applied in past decade. This study presents the relationship of the patent trends and the national R&D investment in 6T areas.

• 산업경영시스템학회지
• /
• 제44권3호
• /
• pp.248-261
• /
• 2021

Scientific and technological performances (e.g., patents and publications) made through R&D play a pivotal role for national economic growth. National governments encourage academia-industry cooperation and thereby pursue continuous development of science technology and innovation. Increasing R&D-related investments and manpower are crucial for national industrial development, but evidence of poor performance in business performance, efficiency, and effectiveness has recently been found in Korea. This study evaluates performance efficiency of the 6T sector (Information Technology, Bio Technology, Nano Technology, Space Technology, Environment Technology, Culture Technology), which is considered a high-potential promising industry for the next generation growth and currently occupies two thirds of the national R&D projects. The study measures the relative efficiency of R&D in a comparative perspective by employing the Data Envelopment Analysis (DEA) method. The result reveals overall low efficiency in basic R&D (0.2112), applied R&D (0.2083), development R&D (0.2638), and others (0.0641), confirming that economic performance and efficiency were relatively poor compared to production efficiency. Efficient R&D needs policy makers to create strategies that can increase overall efficiency by improving productivity performance and quality while increasing economic performance.