• Journal of the Korean Society for Precision Engineering
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• v.14 no.11
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• pp.25-33
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• 1997

This study deals with controlling the velocity of Electr-Hydraulic servo system through the non-stan-dard PIC control. This was done as follows. First, we modeled nonlinearised model and linearised model, second designed analytic program for electro-hydraulic servo system velocity control Lastly, to im- prove dynamic characteristics of system we designed non-standard PID contoller and verifed throughth experi- ment and MATLAB program, commercial used software.

• The Korean Journal of Financial Management
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• v.26 no.3
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• pp.199-226
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• 2009

We examine the intertemporal relation between risk and return in the Korean stock market and foreign exchange market based on the two factor ICAPM framework. The standard GARCH model and the GJR(1993) model are employed to estimate conditional variances of the stock returns and foreign exchange rates. The covariance between the rates of stock returns and changes in the exchange rates are estimated by the constant conditional correlation model of Bollerslev(1990) and the dynamic conditional correlation model of Engle(2002). The multivariate GARCH in mean model and quasi-maximum likelihood estimation method, consequently, are applied to investigate riskreturn relation jointly. We find that the estimated coefficient of relative risk aversion is negative and statistically significant in the post-financial crisis sample period in the Korean stock market. We also show that the expected stock returns are negatively related to the dynamic covariance with foreign exchange rates. Both estimated parameters of conditional variance and covariance in the foreign exchange market, however, are not statistically significant. The GJR model is better than the standard GARCH model to estimate the conditional variances. In addition, the dynamic conditional correlation model has higher explanatory power than the constant correlation model. The empirical results of this study suggest following two points to investors and risk managers in hedging and diversifying strategies for their portfolios in the Korean stock market: first, the variability of foreign exchange rates should be considered, and second, time-varying correlation between stock returns and changes in foreign exchange rates supposed to be considered.

• Proceedings of the CALSEC Conference
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• 2000.08a
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• pp.179-186
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• 2000

ㆍ A sub-set of SGML (Standard Generalized Markup Language) ㆍ A family of standards ㆍ XML 1.0 is the specification that defines what tags, attributes and other XML nodes are ㆍ License-free, platform-independent and well-supported ㆍ Simple ▶ Human-readable, easy to use ㆍ Extensible ▶ A dynamic data model ㆍ Flexible ▶ For handling complex data ㆍ Portable ▶ For cross-platform data exchange ㆍ Standard ▶ Easy to integrate, widely adopted(omitted)

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.27-36
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• 2020

The purpose of this paper is to study on the applicability of the standard design response spectrum from the response spectrum analysis method, mainly applied to pile mooring facilities. To this end, after performing the ProShake 1-dimensional site response considering various geological conditions, the current standard design response spectrum was compared, and the ground-pile model in time history and two-dimensional site response analysis using Abaqus were performed to analyze the dynamic behavior of the ground-pile and to examine the selection method of the reference surface of the response spectrum on the installed slope, respectively. As a result, it was confirmed that no problems were found in the applicability of the current standard design response spectrum and no improvements are needed as well when considering the characteristics of the ground-pile dynamic behavior and the slope of the pile mooring facility.

• Journal of the Korea Society of Computer and Information
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• v.11 no.4 s.42
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• pp.165-174
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• 2006

As context aware service supports a process of context acquisition and reasoning, there are many studies to facilitate the implementation of context aware service. However, these studies have not supported efficiently a user or service mobility that should be supported necessarily in ubiquitous computing environment. Therefore, this study proposes a dynamic context aware service model which supports a dynamic management of context information, service retrieval and composition for interactions between services, and service mobility. Then we design a middleware based on this model and implement the middleware. As the middleware is implemented on the OSGi framework. it can have an interoperability between the devices such as computers, PDA, home appliances, and sensors, because of using the standard interface technologies like UPnP. Jini and so on.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.276-284
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• 1998

Optimum design of bumper beam is investigated using nonlinear CAE structural analysis techniques.In order to minimize its weight, while enhancing structural performances, bumper beam structural analyses were carried out to produce optimum section. Model is composed of bumper beam and stay. First, considering FMVSS safety standard, static strength and energy absorbing capability were estimated for several competitive bumpers through pendulum static analysis, and most promising section was chosen. Next, to ensure dynamic crashworthinesss performance for center pole impact was evaluated for the bumper beam with chosen section through pendulum static analysis, referring to DHS bumper dynamic impact standard. Finally, 2.5 mph bumper beam was designed and its structural performance was estimated. Through this investigation, an optimized bumper beam section with less weight of 20% while maintaining almost equal carshworthiness, compared with a conventional bumper beam section which proved its impact crashworthiness by experiments, was developed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.3
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• pp.309-316
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• 2015

A state-based peridynamic model is able to describe a general constitutive model from the standard continuum theory. The response of a material at a point is dependent on the deformation of all bonds connected to the point within the nonlocal horizon region. Therefore, the state-based peridynamic model permits both the volume and shear changes of the material which is promising to reproduce the complicated dynamic brittle fracture phenomena, such as crack branching, secondary cracks, cascade cracks, crack coalescence, etc. In this paper, the two-dimensional state-based peridynamic model for a linear elastic plane stress solid is employed. The damage model incorporates the energy release rate and the peridynamic energy potential. For brittle glass materials, the impact of the crack-parallel compressive stress waves on the crack branching pattern is investigated. The peridynamic solution for this problem captures the main features, observed experimentally, of dynamic crack propagation and branching. Cascade cracks under strong tensile loading and secondary cracks are also well reproduced with the state-based peridynamic simulations.

• Journal of Oriental Neuropsychiatry
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• v.27 no.2
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• pp.57-65
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• 2016

Objectives The aim of this study was to develop a new Korean psychotherapeutic model in terms of emotion.Methods We compared the five minds mutual restriction therapy with short-term dynamic psychotherapy (STDP). We summarized 4 similarities and 4 differences of these two models of psychotherapy.Results 1. Short-term dynamic psychotherapy (STDP) needs active intervention of the therapist, with a restricted therapeutic focus and session. It blends with the present state of oriental neuropsychiatric clinics, and is suitable for Korean medical psychiatrists to apply short-term dynamic psychotherapy (STDP) to their clinical settings. 2. Short-term dynamic psychotherapy (STDP) and five minds mutual restriction therapy are similar, in that they both mainly use the emotions, needing restricted therapeutic focus and sessions, and active intervention of the therapist. 3. Short-term dynamic psychotherapy (STDP) and five minds mutual restriction therapy are different in their methods of arousing therapeutic emotion, the necessity of the patient being unconscious, the standard of patient selection, and the importance of follow up.Conclusions It is necessary to develop a new Korean psychotherapeutic model, which amalgamates the advantages of both methods of psychotherapy, and considers the present state of clinic. It is necessary that the Korean medical psychiatrists introspect themselves, since they are not merely therapists but also a role model for the patient.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.384-387
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• 2003

Most of the real world phenomena change over time. The ability to represent and to reason geographic data becomes crucial. A large amount of non-standard applications are dealing with data characterized by spatial, temporal and/or uncertainty features. Non-standard data like spatial and temporal data have an inner complex structure requiring sophisticated data representation, and their operations necessitate sophisticated and efficient algorithms. Current GIS technology is inefficient to model and to handle complex geographic phenomena, which involve space, time and uncertainty dimensions. This paper concentrates on developing a fuzzy spatio-temporal data model based on fuzzy set theory and relational data models. Fuzzy spatio-temporal operators are also provided to support dynamic query.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.12
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• pp.2061-2071
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• 2003

The macro-parametric approach, which is a method of CAD model exchange, has recently been proposed. CAD models can be exchanged in the form of a macro file, which is a sequence of modeling commands. As an event-driven commands set, the standard macro file can transfer design intents such as parameters, features and constraints. Moreover it is suitable for the network environment because the standard macro commands are open, explicit, and the data size is small. This paper introduces the concept of the macro-parametric method and proposes its representation using XML technology. Representing the macro-parametric data using XML allows managing vast amount of dynamic contents, Web-enabled distributed applications, and inherent characteristic of structure and validation.