• Journal of the Korean Vacuum Society
• /
• v.19 no.6
• /
• pp.489-494
• /
• 2010

Enhance signal-to-noise ratio, slow positron coincidence Doppler Broadening method has been applied to study of characteristics of $Nb_3Ge$ superconductor film, which were performed from 20 K to 300 K sample temperature near Tc of it. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The S-parameter values between 0.598 and 0.594 were decreased while the temperature were decreasing, that indicated the voids into the samples. The temperature dependence came from specific positron trapping rate into the vacancy-type defects. It is believed that the positrons annihilate with normal-electrons instead of super-electrons in the Nb3Ge superconductor.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.18 no.1
• /
• pp.3-9
• /
• 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.

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.1
• /
• pp.237-250
• /
• 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.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2003.05b
• /
• pp.96-99
• /
• 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
• /
• 1991.10b
• /
• pp.1533-1538
• /
• 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.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.30 no.4
• /
• pp.320-328
• /
• 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.

• Journal of KSNVE
• /
• v.7 no.4
• /
• pp.701-708
• /
• 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.

• Journal of the Korean Mathematical Society
• /
• v.51 no.1
• /
• pp.137-162
• /
• 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
• /
• v.10 no.3
• /
• pp.749-764
• /
• 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.

• Journal of Industrial Technology
• /
• v.31 no.B
• /
• pp.91-98
• /
• 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.