• Journal of the Korea Society of Computer and Information
• /
• v.7 no.4
• /
• pp.16-23
• /
• 2002

Recently, as the result of high technology of computer environments. various types of computer applications have been researched and developed. Ana, because of the growth of the mobile device such as PDA, HPC, and location tracking technology such as GPS, various services that is based on personal locations are provided. For these Mobile GIS, there is needed a development of client for Mobile GIS that is considered about the characteristics of mobile device. So, we design and implement client interface for Mobile GIS in this paper.

• Journal of The Korean Astronomical Society
• /
• v.24 no.1
• /
• pp.117-127
• /
• 1991

Here I report the confirmation of a long-term modulation of a period of $92^{+21}_{-13}$ years with the "time-delay correlation" method on the sunspot data compiled over the last a total of 289 years. This periodicity better specifies the cycle which falls pretty well within Gleissberg cycle, and clearly contrasts with the 55 year grand cycle which Yoshimura (1979) claimed. It is argued that the period-amplitude diagram method. which Yoshimura used, ana lysed peak amplitudes only so that a large number of data were disregarded, and thus was more susceptible to a bias. The planetary tidal force on Sun as for the possible cause to the solar activity was investigated and its possibility was ruled out in view of no period correlation between them.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.8 s.251
• /
• pp.880-888
• /
• 2006

This paper presents the sliding mode control with the perturbation estimator for a nonlinear control system in the presence of perturbations including external disturbances, unpredictable parameter variations, ana unstructured dynamics. The proposed perturbation estimator is based on the Recursive Linear Smoothed Newton predictive algorithm so that it is effective to attenuate an undesired noise in high frequency band and to predict the present perturbation signal from the previous ones. Compared to conventional sliding mode control (SMC) and sliding mode control with perturbation estimation (SMCPE) introduced by Elmali and Olgac, the control algorithm proposed in this study can offer better tracking control performances and more feasible estimation characteristics. The effectiveness and superiority of the proposed control strategy are demonstrated by a series of simulations on the position tracking control of a simple two-link robot manipulator subject to velocity feedback signals including white noises.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2003.05a
• /
• pp.931-939
• /
• 2003

This paper is aimed at proposing a new framework to predict decision performance, by Investigating decision maker's cognitive resonance. We assume that every decision maker has two kinds of schema­emotional schema and rational schema. Cognitive resonance is believed to have a close relationship with the two schemata and decision performance. In literature on decision performance there is no study' seeking relationship among the two schemata ana cognitive resonance. Therefore, our research purposes are twofold: (1) to provide a theoretical basis for the proposed framework describing the causal relationships among two schemata, cognitive resonance, and decision Performance, and (2) to empirically prove its validity applying to. Internet shopping Situation. Based on the questionnaires from 13S- respondents, we used a second order confirmatory factor analysis (CFA) to extract valid constructs, and structural equation model (SEM) to calculate path coefficients and prove the statistical validity of our proposed research model. Experimental results supported our research model with some further research issues.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.2
• /
• pp.45-52
• /
• 1998

The contact roll is often used to regulate the winding tension as well as the entrained air in a wound roll by adjusting the contact force to the winding roll. But the contact force generated by other rolls, like assistant nip rolls, in a winding(or roll changing) process may act as disturbance to the control of the winding tension. In this paper, the mechanism of a roll change process is analysed. Ana, the behavior of the contact and the nip rolls are mathematically modeled. A nonlinear PID(NPID) controller is designed to control the winding tension and to reject the effect of disturbance generated by the nip roll on the winding tension variation. Computer simulation study showed that the performance of the suggested NPID controller is improved compared with that of the PID controller in controlling the winding tension and in rejecting the effect of the disturbance.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.17 no.29
• /
• pp.30-36
• /
• 1994

This paper has provided a systematic technique, the evaluation of the distribution with the NPV ana the derivation of the IRR in the investment alternatives, for the cost estimating analysts. The proposals of investment alternatives are included the venture capital under risk and probabilities at each events, within the cash inflows are occuring at random timing. Therefore. we have considered the followings : 1) the first cash outflow is deterministic. 2) the cash inflows are random variables with known distributions. 3) the lengths of the time intervals between the cash inflows are independently distributed and independent of the cash inflows. In this paper. the first two moments of the distribution, the Laplace Transforms and the convolutions are computed for both independent cash inflows and mutually exclusive alternatives as in the case of quite correlated cash inflows.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.8 no.3
• /
• pp.73-79
• /
• 1984

The purpose of the study is to obtain the basic data of the proper clothing weight according to the subcutaneous fat thickness. This study was done in April and October, and the subjects were 295 male and female college students. Results were as follows: 1. In the case of female students in April, there was no correlation between the subcutaneous fat thickness and the total clothing weight. But there was low negative correlation between the subcutaneous fat thickness and the upper and under clothing weight. 2. In the case of female students in October, there was low negative correlation between the subcutaneous fat thickness and the total, upper, outer clothing weight. 3. In the case of male students in October, there was no correlation between the subcutaneous fat thickness ana the clothing weight.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.19 no.3
• /
• pp.463-470
• /
• 1995

Anthropological measurements concerning 29 items were made on 37 adult males aged from 20 to 60. Factor analysis was applied in all 36 items. The main results are as gallows 1. Neck girth and need base girth are smaller. in the elder croup than the gouger group. 2. These decrease occur in the frontal part of the neck. 3. Neck frontal width decreases with age, but side depth increases. 4. The back part of the body depth at the level of the shoulder increases with age. 5. For the factor analysis, the third factor is a factor of forms, the variations of which has a relation with age.

• Proceedings of the International Microelectronics And Packaging Society Conference
• /
• 2003.11a
• /
• pp.260-264
• /
• 2003

In this paper, a $\lambda/4$ hairpin resonator is proposed to reduce the size of planar resonators for a LTCC MLC bandpass filter. The $\lambda/4$ hairpin resonator operates as stepped impedance resonator (SIR) without changing the width of the planar resonator. It is composed of two sections those are parallel coupled line and transmission line. The characteristic impedance of two sections is different each other. The design formulas of the bandpass filter using the coupling element at the arbitrary position are derived from even and odd-mode analysis. The formulas can take account of the arbitrary coupling of lumped ana/or distributed resonators. The advantage of this filter is its abilities to change freely the coupling structure between two resonators. Experimental bandpass filters for 2.4GHz Band are implemented and their performances are shown.

• Journal of the Korean Mathematical Society
• /
• v.48 no.3
• /
• pp.565-583
• /
• 2011

In this paper we provide characterizations for the Gromov hyperbolicity of some particular Denjoy domains and besides some sufficient conditions to guarantee or discard the hyperbolicity of some others. The conditions obtained involve just the lengths of some special simple closed geodesics in the domain. These results, on the one hand, show the extraordinary complexity of determining the hyperbolicity of a domain and, on the other hand, allow us to construct easily a large variety of both hyperbolic and non-hyperbolic domains.