• 한국진공학회지
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• 제19권6호
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• pp.489-494
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• 2010

저속 에너지 도플러 넓어짐 양전자 소멸 분광법으로 $Nb_3Ge$ 시료내의 원자 크기 정도 고체 구조 특성에 대하여 조사하였다. A15 화합물 구조로 된 $Nb_3Ge$ 시료를 상온에서 초전도 특성을 갖는 상전이 온도 근처의 S-변수를 측정하였다. 양전자와 전자의 쌍소멸로 발생하는 511 keV 감마선 스펙트럼의 수리적 해석 방법인 S-변수를 사용하여, 상전이 근처 온도에서 박막의 구조 변화를 측정하였다. 양전자의 입사 에너지에 따른 S-변수는 0.598에서 0.594로 온도의 변화에 의하여 감소하였으며 이때 초전도 전이와는 무관함을 나타낸다. 고온으로 갈수록 일반적인 트랩핑 비율은 커지고 양전자 흐름은 공공(voids) 근처에서 소멸하는 것이 보였다. 이 결과로부터 양전자가 초전자와 소멸하기 보다는 상전자와 소멸하는 것으로 판단된다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제18권1호
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• pp.3-9
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• 2007

Based on the broad and in-depth literature review, the dedicated members of the committee for the development of Korean attention-deficit hyperactivity disorder (ADHD) practice parameter develop the Korean practice parameter for ADHD. Members of the Korean Academy of child and Adolescent Psychiatry (KACAP) had reviewed the drafts through off-line and on-line access to the drafts. Feedbacks from the members of KACAP were carefully integrated into the current practice parameter. This article presents the state of the art knowledge regarding the assessment and the management of ADHD. Recommendations in the end of the practice parameter may help clinician to make decisions in clinical practice, but are not likely to override the clinician's decision in natural settings. Future directions to complement the limitation of the current practice parameter is suggested.

• 대한인간공학회지
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• 제30권1호
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• pp.237-250
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• 2011

The train transportation has a lot of advantages-energy efficiency is high, it is eco-friendly, safety is better than normal roads and it is possible for people to arrive on time. In these days, the valuation of ride comfort, which is only limited to road transportation, is newly recognized in order to having competitiveness from other transportation. Especially, in the development of the Korean high-speed railroad business, the ride comfort enhancement of train is very important problem to be solved. Currently, there are international standards of ride comfort such as UIC13, ISO2631. In Korea case, although it has own standard like KS R9216, it mainly depends on the physical parameter such as vibration and noise. So recently, in the valuation of ride comfort, the movements of living parameter technique introduction are increasing on the base of Japan and many developed countries of Europe techniques. Presently, the method of train ride comfort is mainly based of vibration, that is, mechanical parameter adding selection of variable acceleration and noise. This paper would like to show biological parameter; heart rate and blood pressure variation. This method is more direct, based on human body response, than mechanical parameter method. In this experiment, the variability of heart rate and blood pressure of passengers according to tilting angle change of Train, the Korean tilting train, we are supposed to know that the extent of tilting on the simulation has influence on variability of heart rate and blood pressure, which are living parameter of heart's blood.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2003년도 춘계학술발표대회논문집
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• pp.96-99
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• 2003

현재 블루투스(Bluetooth) 표준(Specification)에서는 QoS 지원에 대해 L2CAP, LMP 계층(Layer)에서의 QoS 지원 파라미터(parameter)와 협상(Negotiation) 순서에 대해서만 정의되어 있다. 본 논문에서는 블루투스 기기간의 통신시 QoS를 지원하기 위해 현재 블루투스 표준에 정의되어 있는 요소들을 기반으로 한 새로운 QoS 제어 메커니즘(Control Mechanism)을 제안한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1533-1538
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• 1991

A parameter space approach for robust control system design is developed by reducing several design specifications to sign definite conditions. It is shown that the gain and phase margin constraints for the parametric perturbed plant hold if and only if the four Kharitonov systems satisfy the margins. On pole location, it is shown that D-stability of convex combinations (1-t)p(s)+tq(s) can be determined by the coefficients corresponding to p(s) and q(s) based on the sign definite condition. We show a method of PI-type robust control system design as a useful example.

• 수산해양기술연구
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• 제30권4호
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• pp.320-328
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• 1994

In 1980 s to 1990 s the marine propulsion diesel engines have been developed into lower speed and longer stroke for the enegy saving (small S.F.O.C). As these new trends the conventional mechanical-hydraulic governors were not adapted to the new requirements and the digital governors have been adopted in the marine use. The digital governors usually use the control algorithms such as the PID control, optimal control, adaptive control and etc. While the engine has delay time and parameter variations these control algorithms have difficulty in considering the stability and the robustness for the model uncertainty. In this study, the $H_{\infty}$ controller design method are applied in order to design the feedback controller K(s) to the speed control of the low speed marine diesel engine, and the two-degree-of-freedom control system is constituted with $H_{\infty}$controller. By comparison of responses of the two-degree-of-freedom control system under the delay time and parameter variations is confirmed.

• 소음진동
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• 제7권4호
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• pp.701-708
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• 1997

Up to now, numerical methods such as Finite Element Method(FEM) or Boundary Element Method(BEM) have been widely used to find the optimized resonator's position during designing a car intake system. However, these methods are not useful at the first stage of car design since it is not easy to change a numerical model consist of a large mesh size. A software has been developed to cover the defects using 4-pole parameter method. The software is running at Windows 95 environment for a user's convenience. To show its usefulness, it is applied to a real automobile intake system.

• 대한수학회지
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• 제51권1호
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• pp.137-162
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• 2014

In this work we study the local and semilocal convergence of the relaxed Newton's method, that is Newton's method with a relaxation parameter 0 < ${\lambda}$ < 2. We give a Kantorovich-like theorem that can be applied for operators defined between two Banach spaces. In fact, we obtain the recurrent sequence that majorizes the one given by the method and we characterize its convergence by a result that involves the relaxation parameter ${\lambda}$. We use a new technique that allows us on the one hand to generalize and on the other hand to extend the applicability of the result given initially by Kantorovich for ${\lambda}=1$.

• Communications for Statistical Applications and Methods
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• 제10권3호
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• pp.749-764
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• 2003

In this paper we explain that normal theory likelihood-ratio tests(z, t, $x^2$. F) for mean(s) or variance(s) can be geometrically related to volume of difference of two joint pdf's. One is an estimated joint pdf under null parameter space $\omega$ and the other is an estimated joint pdf under full parameter space $\Omega$. For explanations, ‘distance between two distributions’ is defined. We study properties of it, and derive some results on the distance between two multivariate normal distributions.

• 산업기술연구
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• 제31권B호
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• pp.91-98
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• 2011

In this thesis, from the results of settlement measurement performed at the site where embankment earthwork was carried out on the ground consisting of highly plastic and silty soft soils interlayered with organic deposits, various methods of predicting the embankment settlement such as Hoshino's method, Asaoka's method, hyperbolic method, ${\sqrt{s}}$ method and Monden's method were used to investigate their applicability and the inverse method of finding the soil parameter related to consolidation was used to predict the consolidation behavior in the future. It was confirmed that reliable prediction of consolidation behavior under various conditions could be done to estimate soil parameter related to consolidation such as the consolidation index and consolidation coefficient by the inverse method of comparing the measured settlement with the predicted value by the settlement prediction methods.