• Communications for Statistical Applications and Methods
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• v.15 no.6
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• pp.959-967
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• 2008

In this paper we show the weak convergence of the linear random(multistochastic process) field generated by identically distributed 2-parameter array of associated random variables. Our result extends the result in Newman and Wright (1982) to the linear 2-parameter processes as well as the result in Kim and Ko (2003) to the 2-parameter case.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.394-394
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• 2013

The spin-orbit interaction has received great attention in the field of spintronics, because of its property and applicability. For instance, the spin-orbit interaction induces spin precession which is the key element of spin transistor proposed by Datta and Das, since frequency of precession can be controlled by electric field. The spin-orbit interaction is classified according to its origin, Dresselhaus and Rashba spin-orbit interaction. In particular, the Rashba spin-orbit interaction is induced by inversion asymmetry of quantum well structure and the slope of conduction band represents the strength of Rashba spin-orbit interaction. The strength of spin-orbit interaction is experimentally obtained from the Shubnikov de Hass (SdH) oscillation. The SdH oscillation is resistance change of channel for perpendicular magnetic field as a result of Zeeman spin splitting of Landau level, quantization of cyclotron motion by applied magnetic field. The frequency of oscillation is different for spin up and down due to the Rashba spin-orbit interaction. Consequently, the SdH oscillation shows the beat patterns. In many research studies, the spin-orbit interaction was treated as a tool for electrical manipulation of spin. On the other hands, it can be considered that the Rashba field, effective magnetic field induced by Rashba effect, may interact with external magnetic field. In order to investigate this issue, we utilized InAs quantum well layer, sandwiched by InGaAs/InAlAs as cladding layer. Then, the SdH oscillation was observed with tilted magnetic field in y-z plane. The y-component (longitudinal term) of applied magnetic field will interact with the Rashba field and the z-component (perpendicular term) will induce the Zeeman effect. As a result, the strength of spin-orbit interaction was increased (decreased), when applied magnetic field is parallel (anti-parallel) to the Rashba field. We found a possibility to control the spin precession with magnetic field.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.105-113
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• 2019

Convergence education, which is operated by many engineering colleges, is mainly led by government-led projects. Convergence majors are established in consideration of the research field of the university professors rather than systematically analyzing the needs of the industry. The purpose of this study is to present the directions of convergence technology education related to new industry fields by analyzing industry needs. Participants were 299 industrial workers in various fields. Instrument consisted of three parts: necessity for convergence education, demand for convergence new technology education from industry perspective, and opinions about undergraduate convergence education. As a result, it was found that the level of awareness of industry needs for fusion technology education was high, and it was confirmed that there is a high demand for IoT convergence, bio-health, advanced new material, and renewable energy fields among convergence technology fields. In addition, the results of the industry demand for convergence new technology education were presented. The suggestions for expectations, problems, and improvements in undergraduate education were presented and implications for convergence technology education were discussed based on the results of the study.

• Journal of Convergence for Information Technology
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• v.7 no.3
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• pp.147-152
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• 2017

Recently, colleges and universities provide programs of field experience for students to improve career development skills. The purpose of this study was to analyze the effects of participating field experience on communication ability, interpersonal relationship ability, and convergence competence. Data were collected from 1,887 college students, and were analyzed using one-way ANOVA. As a result, students who participated field experience program improved their communication ability, interpersonal relationship ability, and convergence competence. This study is expected to be utilized as basic references to promote field experience program in colleges and universities.

• Korean Journal of Materials Research
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• v.16 no.9
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• pp.550-556
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• 2006

Photosensitive carbon nanotube (CNT) pastes are explored to develop a CNT field emitter for field emission display (FED) application. We formulated a photosensitive paste including multi-walled CNTs (MWNTs) for screen printing. The photosensitive CNT paste was synthesized by mixing of MWNTs, inorganic fillers (nano metal), organic vehicle, monomers and photo initiator. The CNT paste films were patterned by using backside exposure technique. The CNTs were strongly fixed on a cathode by formation of carbon residue during firing process. For the CNT emitters, current-voltage(I-V) characteristics and images of field emission were evaluated. The emission properties of CNT emitters are dependent on the paste composition. A turn-on electric field for the CNT field emitters is measured to be 1 V/$\mu$m. Additionally, the effect of heat treatment parameter on field emission properties was discussed. The newly formulated photosensitive CNT paste can be potentially applicable to highly reliable CNT field emitters.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.1
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• pp.15-26
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• 2022

3D open-field farm model developed from UAV (Unmanned Aerial Vehicle) data could make crop monitoring easier, also could be an important dataset for various fields like remote sensing or precision agriculture. It is essential to separate crops from the non-crop area because labeling in a manual way is extremely laborious and not appropriate for continuous monitoring. We, therefore, made a 3D open-field farm model based on UAV images and developed a crop segmentation model using a supervised machine learning algorithm. We compared performances from various models using different data features like color or geographic coordinates, and two supervised learning algorithms which are SVM (Support Vector Machine) and KNN (K-Nearest Neighbors). The best approach was trained with 2-dimensional data, ExGR (Excess of Green minus Excess of Red) and z coordinate value, using KNN algorithm, whose accuracy, precision, recall, F1 score was 97.85, 96.51, 88.54, 92.35% respectively. Also, we compared our model performance with similar previous work. Our approach showed slightly better accuracy, and it detected the actual crop better than the previous approach, while it also classified actual non-crop points (e.g. weeds) as crops.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.205-211
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• 2018

The purpose of this study is to propose a strategy to educate the core contents of various major fields in practical and convergent ways in universities in order to prepare for the 4th industrial revolution era. First, convergence field is established in the university curriculum in addition to the existing major and the liberal arts field. Second, convergence courses are created in connection with job ability, which are major curriculum but only for students in other departments. Third, convergence courses are organized in the form of module curriculum, which is a small-sized and independent curriculum consisting of 4 courses. D University, one of the local private universities in Korea, has provided such convergence module education since 2016, and satisfactory results have been obtained in the course enrollment rate and the course evaluation, etc. By combining these convergence modules in various ways, it is possible to easily create customized majors required and designed by local companies at low cost.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.185-192
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• 2019

Polymer materials are used in a wide variety of fields such as automobiles, aerospace, energy, IT, and as well as simple household products. Despite high interest in the technological convergence of polymer materials for the sustaining progress, there have been only limited analyzes on the topic. This research attempted to analyze the types of convergence and the level of technology in the polymer materials field. For this purpose, we collected patent information from the PCT database and implemented a co-classification analysis. The research shows that Japan and Korea have more section-level convergence whilst US and Europe focus on field-level convergence. In terms of the quality measured by patent activity, patent competitiveness, and patent effect, Korean convergence technologies seem to be inferior to those of other countries.

• Journal of Korea Multimedia Society
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• v.18 no.12
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• pp.1432-1438
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• 2015

We present a methodology to detect moving shadows in video sequences, which is considered as a challenging and critical problem in the most visual surveillance systems since 1980s. While most previous moving shadow detection methods used hand-crafted features such as chromaticity, physical properties, geometry, or combination thereof, our method can automatically learn features to classify whether image segments are shadow or foreground by using a deep learning architecture. Furthermore, applying Markov Random Field enables our system to refine our shadow detection results to improve its performance. Our algorithm is applied to five different challenging datasets of moving shadow detection, and its performance is comparable to that of state-of-the-art approaches.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.833-844
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• 2023

As technology convergence is recognized as a driver of innovation, the identification of technology convergence opportunities is critical to expanding a firm's technology portfolio. Recently, wearable technology has emerged as an important factor in creating new business opportunities and providing technology investment alternatives for firms in the era of Industry 4.0. Against this background, this study provides a new patent analysis framework for identifying and proposing technology convergence opportunities in the wearable field. Using 8,621 patents filed between 2011 and 2021, a case study was conducted to identify technological convergence opportunities by applying Word2Vec algorithm. The analysis framework can be divided into four stages, with the final stage recommending potential technology convergence opportunities for a specific candidate firm's technology area by calculating similarities between technology codes. This study aims to better understand the current status of wearable technology development as well as to propose a new methodology for capturing technology convergence opportunities in the wearable industry. The case study result suggests that the convergence of healthcare and ICT may provide new development opportunities. Furthermore, the results are expected to provide alternative perspectives on the development of new markets and technologies using wearable technology and can support the strategic decision-making on future technology planning in the wearable field.