• Journal of the Korean Data and Information Science Society
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• v.25 no.4
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• pp.715-725
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• 2014

This study uses a quantile regression analysis to investigate intergenerational economic mobility in Korea. The analysis is based on data from the 1st through 11th waves of the Korean Labor and Income Panel Study (KLIPS) conducted from 1998-2008. The household nature of the data allows us to link parents' incomes to children's incomes at different points in time. Using a quantile regression analysis instead of mean one reveals that the effect of fathers' earnings are different across the conditional distribution of sons' earnings, particularly being larger on the upper quantile than on the lower quantile. After controlling effect of sons' college education by including a dummy variable for the degree, however, the pattern among quantile effects for fathers' earnings is no longer clear. Instead a new pattern emerges that education has a much larger effect on the upper quantiles than on the lower ones. Using nonparametric estimates of conditional density curves based on the quantile regression results, we derive some interesting features in graphical forms, which are not obvious in numerical analysis.

• Fashion & Textile Research Journal
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• v.25 no.2
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• pp.199-209
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• 2023

This study identified design elements of the functions required for children's ski pants. Data for this study were collected through questionnaire surveys conducted among children's ski instructors and children's sportswear developers. Five functionalities of children's skiwear were evaluated: mobility, stability, comfort, protection, and convenience. A total of 25 functional design elements related to the patterns, design details, and physical characteristics of fabrics for ski garments, were evaluated. The results of this study are as follows. First, children's sportswear developers evaluated that the pattern elements were important. Most of the pattern design elements highly related to mobility. Children's ski instructors' appraisal was that the height of the back waist was the important feature. Second, regarding the design details, children's ski instructors evaluated the size adjustment function and ventilation system as important elements. Many design detail elements were highly related in respect of stability, comfort, protection, and convenience. Third, the physical characteristics of fabric were strongly associated with mobility, comfort, and protection. As regards the physical characteristics of fabric, children's ski instructors valued anti-fouling highly, but children's sportswear developers attached more importance to the weight of the fabric. The results of this study will be useful in designing functional ski pants for children of elementary and intermediate ski levels. Since there may be limitations related to the ski level and age of children wearing ski pants, it is suggested that follow-up studies according to various groups of the ski pant wearers should be done.

• The Research Journal of the Costume Culture
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• v.25 no.2
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• pp.224-236
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• 2017

Kimono sleeves have continuously appeared in modern fashion as a design motif and this trend has become increasingly prevalent recently. However for research in the area of clothing composition for kimono sleeves in Korea, there has been a lack of development of master patterns based on basic data from the analysis of the standard body type of Korean people and finalized designs based on comparative experiments and analysis of pre-existing research Thus, there is no ideal master kimono sleeve pattern development research based on the examination of the results of the analysis of the standard body type of Korean people. Therefore by recognizing the importance of developing a master kimono sleeve pattern, this research aims to present a practical master kimono sleeve pattern for the standard body type of someone in their 30s. First, the four master patterns were collected and a dressing evaluation was conducted, and by selecting and improving one of these master designs, a final research master pattern was developed after a second dressing evaluation. Through this research, it was possible to design a master kimono sleeve pattern appropriate both externally and functionally for the standard body type of someone in their 30s, which has not been a consideration in previous research.

• Journal of the Korean Society of Costume
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• v.59 no.2
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• pp.29-41
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• 2009

Perception between real object and recognized subject of human on objective subject is not the same. The reason Is that individual perception of visual design components are transmitted as the image of whole. It is required process of visual perception. Therefore, I developed the vision of seeing image of pattern which is based on Gestalt visual perception theory in clothes. The summary of this study's results is like followings. Extremely antagonistic terms which are specialized by formative characteristics of formative components are clearness and blur of outline/ fixed shape and non-fixed shape/ visuality and tangibility of representation/ simplicity and complexity of structure/ invariability and variability of mobility/ symmetry and asymmetry of arrangements singularity and plurality of group number. The expression of motive shows that clearness, fixed shape, visuality and simplicity pursuit Determination image, and blur, non-fixed shape, tangibility and complexity pursuit Ambiguity image. The arrangements of motive shows that invariability, symmetry and singularity pursuit Order image, and variability asymmetry and plurality pursuit Disorder image. Therefore, the standard of the coordinator of Pattern image positioning is established as Determination and Ambiguity of motive are X-axis, and Order and Disorder of pattern are Y-axis. As the frame of Pattern image positioning, four separated dimensions have made.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.120.1-120.1
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• 2015

We investigate the degradation pattern of Black phosphorus (BP) field effect transistor (FETs) investigated by using an mechanically exfoliated BP that react O2 and water vapor in ambient condition, degradation. The BP FETs was electrically measured every 20 minutes (1cycle) in the air, the total cycle is 100. We show electrical changes with Mobility, On/off ratio, Current and a significant positive shift in the threshold voltage. We extracted the current level at Vgs-Vth = 0, -10, -20 and fitting with Swiss-cheese model. This model suggested that Swiss-cheese model is well fitted with degradation pattern of BP FETs.

• Journal of Korea Multimedia Society
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• v.17 no.8
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• pp.946-952
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• 2014

Mobility prediction is one of hot topics using location history information. It is useful for not only user-level applications such as people finder and recommendation sharing service but also for system-level applications such as hand-off management, resource allocation, and quality of service of wireless services. Most of current prediction techniques often use a set of significant locations without taking into account possible location information changes for prediction. Markov-based, LZ-based and Prediction by Pattern Matching techniques consider interesting locations to enhance the prediction accuracy, but they do not consider interesting location changes. In our paper, we propose an algorithm which integrates the changing or emerging new location information. This approach is based on Active LeZi algorithm, but both of new location and all possible location contexts will be updated in the tree with the fixed depth. Furthermore, the tree will also be updated even when there is no new location detected but the expected route is changed. We find that our algorithm is adaptive to predict next location. We evaluate our proposed system on a part of Dartmouth dataset consisting of 1026 users. An accuracy rate of more than 84% is achieved.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.10
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• pp.2473-2492
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• 2012

Energy conservation is a vital issue in wireless sensor networks. Recently, employing mobile sinks for data gathering become a pervasive trend to deal with this problem. The sink can follow stochastic or pre-defined paths; however the controlled mobility pattern nowadays is taken more into consideration. In this method, the sink moves across the network autonomously and changes its position based on the energy factors. Although the sink mobility would reduce nodes' energy consumption and enhance the network lifetime, the overhead caused by topological changes could waste unnecessary power through the sensor field. In this paper, we proposed EEDARS, an energy-efficient dual-sink algorithm with role switching mechanism which utilizes both static and mobile sinks. The static sink is engaged to avoid any periodic flooding for sink localization, while the mobile sink adaptively moves towards the event region for data collection. Furthermore, a role switching mechanism is applied to the protocol in order to send the nearest sink to the recent event area, hence shorten the path. This algorithm could be employed in event-driven and multi-hop scenarios. Analytical model and extensive simulation results for EEDARS demonstrate a significant improvement on the network metrics especially the lifetime, the load and the end-to-end delay.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.2
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• pp.217-223
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• 2014

Recently, various researches and projects about electric vehicles are in progress vigorously and continuously and it is expected to penetrate rapidly with the next a few years. This deployment will cause the change of load composition rate affecting on power system planning and operations. Therefore, a new load model should be developed integrating with electric vehicle loads. In this paper, the load composition rate of residential sectors is analyzed considering the deployment of this mobility load such as electric vehicles and a new diffusion model is proposed based on the classification of the replacement patterns. Additionally, electric vehicle charging loads are basically modeled by some individual load experiments to develop new load models for smart place and some new conceptual power systems such as micro grids.

• The Journal of Korean Association of Computer Education
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• v.8 no.6
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• pp.123-132
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• 2005

There are many research results for the location update cost minimization of location management in cellular networks. For minimizing the location update cost, we have to take in consideration of each users' mobility pattern. This paper suggests location area list generation and a 3-step paging method based on users' movement history with the users' profiles. Users' mobility has not only geographical regular patterns but also time-related regularity. So, the method extracts users' movement regularities in both geography and time from their movement history, and generate location area list considering the regularities. For the performance analysis of the suggested method, we have executed a simulation for suggested method with user's mobility model. The results of the simulation show that suggested algorithm has some merits in the location management cost.

• The Transactions of the Korea Information Processing Society
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• v.7 no.4
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• pp.1217-1226
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• 2000

Traditionally, Mobile Teletraffic model consists of two sub-models, i.e. the network traffic model and the traffic source model. In this paper, we present the traffic source model by developing MobCall (Mobile Call Simulator) which analyses various mobile wireless environments based on regional characteristics that the base stations are located. User mobility is presented by regional average vehicle speeds and the transportation share rate. Moreover, the user mobility on subway, which is increasing in urban area, is considered in MobCall. And also, user's movements on highway are considered in MobCall. The object-oriented simulation platform, C++SIM, is used to implement MobCall. Using MobCall, the accumulated number of calls in residential and commercial regions, the handoff rate with respect to traffic sources of Seoul, the handoff rate on highway, and the handoff rate according to the call duration are presented. MobCall enables the simulation of dynamic handoff buffering and functional entity control of one base station according to the changes in user's calling pattern at the design phase. Also, when a new town is under construction by a detailed plan, MobCall is used to design the mobile network with regional characteristics and user mobility considered.