• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.709-712
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• 1998

A new ZVS-CV PWM converter with power factor correction (PFC) function is presented in this paper. The new topology is a integration of a boost converter and a ZVS-CV topology in a single power conversion stage. The new converter can be regulated in pulse-width modulation (PWM) by universal integrated control circuits. Some design considerations are given in detail. A laboratory prototype has been implemented to show the feasibility of the approach and the analysis.

• Electronics and Telecommunications Trends
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• v.8 no.4
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• pp.79-96
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• 1993

개인 통신의 최고급 형태인 UPT(Universal Personal Telecommunication) 서비스를 실현하기 위해서 3 종류의 이동성 즉 개인 이동성, 단말기 이동성, 서비스 이동성에 대해 고려해야 한다. 본 고에서는 UPT 서비스 구현에 있어서 3 종류의 이동성에 대한 정의와 더불어 UPT 서비스에서 각 이동성의 적용 및 관리 방안 등을 ITU-TS, 논문 등에서 제시한 여러 방법을 중심으로 정리하였다.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.40.4-40
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• 2001

This paper addresses the problem of designing robust adaptive output tracking control for a class of MIMO nonlinear systems which have different number of inputs and outputs The stability of the whole closed-loop system is guaranteed in the sense of Lyapunov and uniformly Itimately boundedness of the tracking error vector as well as estimated parameters are shown. In addition, we show that the restrictive assumptions on input gain matrix which is presumed in the past works can be eliminated by using proposed control law.

• Proceedings of the Korean Society for Language and Information Conference
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• 2001.06a
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• pp.237-257
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• 2001

This paper investigates the idiosyncratic understanding of universal quantifiers such as every, each or all by young children at the ages of 4 to 7, and argues that the phenomenon is explicable in terms of the maturation of both the cognitive system and the linguistic system. Evidence for this dual explanation comes from the fact that the visual input, a picture, plays a key role in determining the children’s conceptual representation, suggesting the need for the central integration of visual and linguistic elements; and from the fact that a quantifier in the linguistic input has an intrinsic property, i.e. a <+focus> feature. I have tried to explain the nature of the cognitive factors in terms of the function of the central system, suggesting a modified form of Smith & Tsimpli’s (1995) version of Fodor’s (1983) modularity hypothesis. Conceptual representations of two kinds are in competition with each other and they are integrated into a neutral LOT (Language of Thought) representation at some point . In the process of this integration, the representations from the visual input predominate over those from the auditory input, though the quantize. (treated as new information provided by the latter) is salient in the final representations. When visual conceptual representations predominate over purely linguistic ones, quantifier spreading errors occur. By contrast, when the relevant grammatical knowledge has developed sufficiently to counteract the conceptual representations, this peculiar behaviour by children should disappear. It is argued that children have to learn two kinds of grammatical fact with regard to universal quantification: (i) they have to learn the status of the quantifier as a functional head of DP so that it has to be positioned inside DP; and (ii) they have to learn the Left-Branch Condition which specifies that movement of an element in the left-branch position is possible only by pied-piping the entire phrase.

• Journal of Acupuncture Research
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• v.18 no.2
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• pp.1-17
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• 2001

Background and Objetive : Lack of uniformity in reporting facial nerve recovery in patients with facial nerve paralysis has been a major disadvantage in comparing treatment modalities. The objective evaluation of facial nerve function is a complex procedure. The House and Brackmann grading system, the Yanagihara grading system has been recommend as a universal standard for assessing the degree of facial nerve palsy. However, clinical studies for treatment of facial palsy have rarely used this universal standard in oriental medicine. That is the reason for analysing this facial nerve grading system. Material and Method : We choose 10 scales reported from 1955 till 1995. These facial nerve grading systems may be classified as Gross system, Regional system and Specific system. Result and Conculsion : The scales of Botmann and Jonkees, May, Peitersen, and House and Brackmann are the gross facial nerve grading systems with which we grossly assess the facial motor dysfunction and the secondary defect. Among these scales, H-B scale is the most widespred The scales of Yanagihara(若杉文吉), Smith, Adour and Swanson, Jassen, FEMA are the regional facial nerve grading system in which we weight, or unweight the facial motor dysfunction and the secondary defect. For example, the scales of Yanagihara(若杉文吉) and Smith are the unweighted regional scale, the scale of Adour and Swanson, Jassen, FEMA are the weighted regional grading system. The scale of Stennert is the Specific facial nerve grading system in which we respectively assess the grade of facial dysfunction at rest, in motion and the secondary defect. For the objective evaluation of the oriental medicine treatment for facial palsy, we must use the universal standard scale, i.e. the H-B scale, the Yanagihara scale.

• Korean Journal of Remote Sensing
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• v.1 no.1
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• pp.5-27
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• 1985

A hill-sliding technique was devised to extract Gaussian clusters from the multivariate probability density estimates of sample data for the first step of iterative unsupervised classification. The underlying assumption in this approach was that each cluster possessed a unimodal normal distribution. The key idea was that a clustering function proposed could distinguish elements of a cluster under formation from the rest in the feature space. Initial clusters were extracted one by one according to the hill-sliding tactics. A dimensionless cluster compactness parameter was proposed as a universal measure of cluster goodness and used satisfactorily in test runs with Landsat multispectral scanner (MSS) data. The normalized divergence, defined by the cluster divergence divided by the entropy of the entire sample data, was utilized as a general separability measure between clusters. An overall clustering objective function was set forth in terms of cluster covariance matrices, from which the cluster compactness measure could be deduced. Minimal improvement of initial data partitioning was evaluated by this objective function in eliminating scattered sparse data points. The hill-sliding clustering technique developed herein has the potential applicability to decomposition of any multivariate mixture distribution into a number of unimodal distributions when an appropriate diatribution function to the data set is employed.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.53.2-53.2
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• 2021

Quasar luminosity function (QLF) shows the active galactic nucleus (AGN) demography as a result of the combination of the growth and the evolution of black holes, galaxies, and dark matter halos along the cosmic time. The recent wide and deep surveys have improved the census of high-redshift quasars, making it possible to construct reliable ultraviolet (UV) QLFs at 2 < z < 6 down to M1450 = -23 mag. By parameterizing these up-to-date observed UV QLFs that are the most extensive in both luminosity and survey area coverage at a given redshift, we show that the UV QLF has a universal shape, and their evolution can be approximated by a pure density evolution (PDE). In order to explain the observed QLF, we construct a model QLF employing the halo mass function, a number of empirical scaling relations, and the Eddington ratio distribution. We also include the outshining of AGN over its host galaxy, which made it possible to reproduce a moderately flat shape of the faint end of the observed QLF (slope of ~ -1.1). This model successfully explains the observed PDE behavior of UV QLF at z > 2, meaning that the QLF evolution at high redshift can be understood under the framework of halo mass function evolution. The importance of the outshining effect in our model also implies that there could be a hidden population of faint AGNs (M1450 > -24 mag), which are buried under their host galaxy light.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.1
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• pp.7-13
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• 1985

Design techniques for programmable storage/logic arrays(SLA's) with easily testable features are discussed. The easily testable SLA's will be designed by using additional hardware to provide an easy means to set or check the states. These augmented SLA's have the very short universal test sequences such that the test patterns and responses are uniquely determined only by the size of the SLA's independently of the function of them. The types of faluts considered here are single and multiple stuck faults, crosspoint faults, and bridge faults in SLA's. Fault location and reapir of SLA's are also considered.

• Journal of Communications and Networks
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• v.7 no.4
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• pp.471-477
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• 2005

This paper proposes an efficient constraint-based optimization model for the design of 3G mobile networks, such as universal mobile telecommunications system (UMTS). The model concerns about finding a set of sites for locating radio network controllers (RNCs) from a set of pre-defined candidate sites, and at the same time optimally assigning node Bs to the selected RNCs. All these choices must satisfy a set of constraints and optimize an objective function. This problem is NP-hard and consequently cannot be practically solved by exact methods for real size networks. Thus, this paper proposes a hybrid search strategy for tackling this complex and combinatorial optimization problem. The proposed hybrid search strategy is composed of three phases: A constraint satisfaction method with an embedded problem-specific goal which guides the search for a good initial solution, an optimization phase using local search algorithms, such as tabu algorithm, and a post­optimization phase to improve solutions from the second phase by using a constraint optimization procedure. Computational results show that the proposed search strategy and the model are highly efficient. Optimal solutions are always obtained for small or medium sized problems. For large sized problems, the final results are on average within $5.77\%$ to $7.48\%$ of the lower bounds.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.3 s.96
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• pp.290-296
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• 2005

This paper proposes the modeling scheme of the Miniature Universal Testing Machine (MUTM) composed of 36 thin-beam-type bimorph PZTs and the control algorithm to minimize the residual vibration of the MUTM in the dynamic testing of specimens. In the operation of the MUTM, hysteresis, residual displacement and vibration of it are major issues. From the analysis of the MUTM behaviors, the hysteresis is described by the curving fitting scheme with the function of an input voltage. The dynamic characteristics of the MUTM are identified by the frequency domain modeling technique based on the experimental data. The interested bandwidth is focused on 125-315HZ for effective modeling and control. For the robust vibration control of the MUTM, the sliding mode control and the Kalman filter as observer are proposed. The paper also proposes the best input signal type to operate the MUTM effectively. The feasibility of the proposed modeling scheme and control algorithm are tested and verified experimentally.