• Defense and Technology
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• no.8 s.186
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• pp.36-45
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• 1994

이 글은 미국인간공학학회 제26차 연례학술대회(1982)에서 소개된 내용으로, 본 논문의 저자들은 F/A-18 항공기 개발사업에 참여한 Lioyrd Hicthcock 박사(미연방 항공국), Stephen C. Merriman(미해군 항공기 개발센타), Julian P. Moore(MDC : 맥도널 더글라스 항공사), Peter Field 미해병대 중령(시험비행조종사)이며, 이들이 미해군 항공기 조종사와 정비사들의 인간공학적 요구사항을 초기설계 개발단계에서부터 시험비행 완료단계까지 약 10년간의 F/A-18 항공기 개발기간 동안에 F/A-18 항공기에 적용한 인간공학계획을 회고하는 내용이다. 세계 초일류 항공기 개발 항공사인 맥도널 더글라스 항공사가 F/A-18 항공기를 개발하며서 어떠한 기술이 부족하여 미해군/해병대의 조종사/정비사들을 각각 수십명씩 핵심 개발팀에 합류시켜 공동 개발하였는가?를 자세히 소개하고 있다.

• Journal of applied mathematics & informatics
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• v.26 no.5_6
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• pp.1011-1020
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• 2008

The problem of finding Cramer rule for solutions of some restricted linear equation Ax = b has been widely discussed. Recently Wang and Qiao consider the following more general problem AXB = D, $R(X){\subset}T$, $N(X){\supset}\tilde{S}$. They present the solution of above general restricted matrix equation by using generalized inverses and give an explicit expression for the elements of the solution matrix for the matrix equation. In this paper we re-consider the restricted matrix equation and give an equivalent matrix equation to it. Through the equivalent matrix equation, we derive condensed Cramer rule for above restricted matrix equation. As an application, condensed determinantal expressions for $A_{T,S}^{(2)}$ A and $AA_{T,S}^{(2)}$ are established. Based on above results, we present a method for computing the solution of a kind of restricted matrix equation.

• Journal of International Society for Simulation Surgery
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• v.4 no.1
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• pp.21-23
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• 2017

Purpose In this paper, we proposed alternate neighborhood system and reverse spread-direction approach for accurate and fast cellular automata-based image segmentation method. Materials and Methods On the basis of a simple but effective interactive image segmentation technique based on a cellular automaton, we propose an efficient algorithm by using Moore and designed neighborhood system alternately and reversing the direction of the reference pixels for spreading out to the surrounding pixels. Results In our experiments, the GrabCut database were used for evaluation. According to our experimental results, the proposed method allows cellular automata-based image segmentation method to faster while maintaining the segmentation quality. Conclusion Our results proved that proposed method improved accuracy and reduced computation time, and also could be applied to a large range of applications.

• Journal of the Korean Chemical Society
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• v.47 no.3
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• pp.229-236
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• 2003

Butenolides are prepared from cyclobutenediones when cyclobutenediones are treated with lithium trimethylsilylacetylene, and quenched with water. A plausible mechanism, which contains an allene as an intermediate, is proposed. The usual diradical intermediate may not be formed because of the bulkiness of trimethylsilyl group, and the allenic intermediate may be stabilized by the ${\alpha}$-silyl group.

• Journal of the Korean Magnetics Society
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• v.6 no.4
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• pp.272-276
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• 1996

1948년 Harvard 대학의 Purcell교수와 Stanford 대학의 Bloch교수가 핵자기 공명(Nuclear Magnetic Resonance : NMR) 현상을 발견한 이래로 NMR은 물질의 분자단위에서 화학적, 물리학적 성질을 밝혀내는 탁월한 방법으로 널리 이용되어 왔다. NMR 현상을 이용한 영상촬영법(Magnetic Resonance Imaging, MRI)은 1970년대초 Lauterber와 Damadian 교수가 처음 영상을 얻을 수 있다는 가능성을 제시한 이후 급속한 발전을 하여 1980년대 초에는 Moore와 Holland에 의해 의학분야에 응용 가능할 정도의 영상이 얻어졌다. 1980년대 중반부터 상용화 되었으며 최근 그 기법도 NMR현상과 연관된 파라미터인 $T_{1}$, $T_{2}$는 물론 혈류의 속도, 자화율, 확산(Diffusion), Perfusion의 영상기법을 비롯해 혈관조영술(MR Angiography), 뇌기능영상(Functional Imaging)등 과거에는 상상도 할 수 없었던 다양한 영상기법 개발되었다. 여기서는 먼저 MRI의 원리를 설명한 후 MRI의 여러 촬영기법들과 그 응용에 관해 설명하겠다.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.4
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• pp.61-68
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• 2001

A new approach for motion control of constrained mechanical systems is proposed in this paper. The approach uses a new equations of motion which is proposed by Udwadia and Kalaba and named Udwadia-Kalaba's equations of motion in this paper. This paper reveals that the Udwadia-Kalaba's equations of motion is more adequate to model constrained mechanical systems rather than the famous Lagrange's equations of motion at least for control purpose. The proposed approach coverts most of constraints including holonomic and nonholonomic constraints. Comparison of simulation results of two systems which are well-known in the literature show the superiority of the proposed approach. Furthermore, a special constrained mechanical system which includes nonlinear generalized velocities in its constraint equations, which has been considered to be difficult to control, can be controlled easily. It shows the possibility of the proposed approach to being a general framework for motion control of constrained mechanical systems with various kinds of constraints.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.1891-1894
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• 2014

In February 6-7th, the Thai National Cancer Institute, the International Agency for Research on Cancer and its Mumbai Hub for Cancer Registration, together with the International Association of Cancer Registries and the APOCP/APJCP, jointly organized an Asian cancer registry forum to discuss regional cooperation for cancer registration. Held in the Grande Mercure Fortune Hotel, Bangkok, the meeting brought together leading scientists in cancer registration from South-East and North-East Asia as well as Australia, India and Iran and IARC itself, with coverage of various priorities and challenges of cancer registries regarding cancer control policy, operational parameters, assessment of survival and contributions to screening, for example. The current situation was highlighted and future directions and possible expansion of activities were discussed, with especial attention to the necessity for networks to help improve cancer registration across Asia and Africa.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4461-4484
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• 2013

Cancer registration provides a firm basis for cancer control efforts and research into changing patterns of incidence, mortality, survival and prevalence is of obvious importance. Most of the countries of Asia have already published relevant data although the level of coverage and accuracy do vary a great deal both between and within countries. The present review concerns the relevant literature for the period 2008-2013, focusing on the types of research conducted and the conclusions that can be drawn with regard to what should be done in the future to translate the information available into effective intervention efforts to reduce the burden of disease. A major emphasis has been on determining variation in incidence and mortality/survival on the basis of ethnicity and socioeconomic as well as geographical background, as well as trends over time, either for cancer in general or specific organ sites. In addition a small number of papers focused on methodological, quality and cancer control issues, very pertinent to the future development of cancer registry based research.

• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.51-67
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• 2004

A matrix pair $(X_0,\;Y_0)$ is called a Hermitian nonnegative-definite(respectively, positive-definite) solution to the matrix equation $GXG^*\;+\;HYH^*\;=\;C$ with unknown X and Y if $X_{0}$ and $Y_{0}$ are Hermitian nonnegative-definite (respectively, positive-definite) and satisfy $GX_0G^*\;+\;HY_0H^*\;=\;C$. Necessary and sufficient conditions for the existence of at least a Hermitian nonnegative-definite (respectively, positive-definite) solution to the matrix equation are investigated. A representation of the general Hermitian nonnegative-definite (respectively positive-definite) solution to the equation is also obtained when it has such solutions. Two presented examples show these advantages of the proposed approach.

• Journal of Mechanical Science and Technology
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• v.18 no.10
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• pp.1691-1699
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• 2004

The objective of this study is to present an accurate and simple method to describe the motion of constrained mechanical or structural systems. The proposed method is an elimination method to require less effort in computing Moore-Penrose inverse matrix than the generalized inverse method provided by Udwadia and Kalaba. Considering that the results by numerical integration of the derived second-order differential equation to describe constrained motion veer away the constrained trajectories, this study presents a numerical integration scheme to obtain more accurate results. Applications of holonomically or nonholonomically constrained systems illustrate the validity and effectiveness of the proposed method.