• Title/Summary/Keyword: Youngsun

Search Result 212, Processing Time 0.028 seconds

A Model to Calibrate Expressway Traffic Forecasting Errors Considering Socioeconomic Characteristics and Road Network Structure (사회경제적 특성과 도로망구조를 고려한 고속도로 교통량 예측 오차 보정모형)

  • Yi, Yongju;Kim, Youngsun;Yu, Jeong Whon
    • International Journal of Highway Engineering
    • /
    • v.15 no.3
    • /
    • pp.93-101
    • /
    • 2013
  • PURPOSES : This study is to investigate the relationship of socioeconomic characteristics and road network structure with traffic growth patterns. The findings is to be used to tweak traffic forecast provided by traditional four step process using relevant socioeconomic and road network data. METHODS: Comprehensive statistical analysis is used to identify key explanatory variables using historical observations on traffic forecast, actual traffic counts and surrounding environments. Based on statistical results, a multiple regression model is developed to predict the effects of socioeconomic and road network attributes on traffic growth patterns. The validation of the proposed model is also performed using a different set of historical data. RESULTS : The statistical analysis results indicate that several socioeconomic characteristics and road network structure cleary affect the tendency of over- and under-estimation of road traffics. Among them, land use is a key factor which is revealed by a factor that traffic forecast for urban road tends to be under-estimated while rural road traffic prediction is generally over-estimated. The model application suggests that tweaking the traffic forecast using the proposed model can reduce the discrepancies between the predicted and actual traffic counts from 30.4% to 21.9%. CONCLUSIONS : Prediction of road traffic growth patterns based on surrounding socioeconomic and road network attributes can help develop the optimal strategy of road construction plan by enhancing reliability of traffic forecast as well as tendency of traffic growth.

Heating Effect of Greenhouse Cultivated Mangos by Heat Pump System using Underground Air as Heat Source (지하공기 이용 히트펌프시스템의 망고온실 난방효과)

  • Kang, Younkoo;Kim, Younghwa;Ryou, Youngsun;Kim, Jongkoo;Jang, Jaekyoung;Lee, Hyoungmo
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.200.1-200.1
    • /
    • 2011
  • Underground air is a special energy source in Jeju and distributes lava cave, pyroclastic, open joint, and crushing zone. A possible area to utilize underground air is 85% of Jeju except to the nearby area of Sambang Mt. and 25m high coastal area from sea level. In Jeju, underground air is used for heating agricultural facilities such as greenhouse cultivated mangos, Hallbong and mandarin orange, pigsty, mushroom cultivation house, etc. and fertilizing natural $CO_2$ gas by suppling directly into agricultural facilities. But this heating method causes several problem because the underground air has over 90% relative humidity and is inadequate in heating for crops. Mangos are the most widely grown tropical fruit trees and have been cultivated since 1993 in Jeju. In Jeju, the cultivating area is about 20ha and amount of harvest is 275ton/year in 2010. In this study, the heat pump system using underground air as heat source was installed in mangos greenhouse which area is $495m^2$. The capacity of heat pump system and heat storage tank was 10RT, 5ton respectively and heating effect and heating performance of the system were analysed.

  • PDF

Conservation Method of Sindu-ri Coastal Dune using System Dynamics (시스템 다이내믹스를 이용한 신두리 해안사구의 보전방안)

  • Seok, Youngsun;You, Soojin;Song, Kihwan;Chon, Jinhyung
    • Korean System Dynamics Review
    • /
    • v.16 no.1
    • /
    • pp.5-23
    • /
    • 2015
  • The purpose of this study is to analyze the land-use changes in the coastal areas using system dynamics modeling and to provide directions for effective management to maintain coastal dune areas. This research process consists of four steps: First, we built the basic model based on the causal loop diagram which was analyzed the land-use change of Sindu-ri Coastal Dune. Second, a time series land-use change map using Arc Map was established. Third, the validity of the basic model was tested. Finally, three simulations were performed for the cut over area($100,000m^2/y$, $150,000m^2/y$, $200,000m^2/y$) of windbreak for maintaining the coastal dune areas. Simulation of the basic model showed that the area of the coastal dune will be consistently decreased. Based on the simulation, if windbreak were cut down $150,000m^2/y$, windbreak area will be restored to the target area in 2019. This study has the limitation which the simulation is progressed with a limited variable: area. Therefore, the modeling of coastal dune should be reflected various variables in the further study.

Analysis of Teachers' Perception and Application Status of Science Subject Competencies of 2015 Revised Curriculum in Elementary Schools (2015 개정 교육과정 과학과 교과역량에 대한 초등교사의 인식과 적용 실태 분석)

  • Ha, Jihoon;Shin, Youngjoon;Kwak, Youngsun
    • Journal of Korean Elementary Science Education
    • /
    • v.39 no.2
    • /
    • pp.219-227
    • /
    • 2020
  • The purpose of this study was to analyze field application of science subject competences of the 2015 revised curriculum for the second year of application. For this purpose, a survey with 133 elementary school teachers, and in-depth interviews with 10 teachers were conducted. According to the results, elementary school teachers had a positive awareness toward the science subject competence, which is a characteristic of the 2015 revised science curriculum, and teachers were applying the science subject competence to their own classes. This tendency was stronger in teachers in science-leading schools than in teachers in regular schools. Teachers wanted support for applying science subject competencies to their classes. To support this, it is necessary to provide the curriculum materials focused on science subject competencies, reinforce teacher training on competence-related curriculum, and activate the professional teacher community.

A Face Robot Actuated With Artificial Muscle Based on Dielectric Elastomer

  • Kwak Jong Won;Chi Ho June;Jung Kwang Mok;Koo Ja Choon;Jeon Jae Wook;Lee Youngkwan;Nam Jae-do;Ryew Youngsun;Choi Hyouk Ryeol
    • Journal of Mechanical Science and Technology
    • /
    • v.19 no.2
    • /
    • pp.578-588
    • /
    • 2005
  • Face robots capable of expressing their emotional status, can be adopted as an efficient tool for friendly communication between the human and the machine. In this paper, we present a face robot actuated with artificial muscle based on dielectric elastomer. By exploiting the properties of dielectric elastomer, it is possible to actuate the covering skin, eyes as well as provide human-like expressivity without employing complicated mechanisms. The robot is driven by seven actuator modules such eye, eyebrow, eyelid, brow, cheek, jaw and neck module corresponding to movements of facial muscles. Although they are only part of the whole set of facial motions, our approach is sufficient to generate six fundamental facial expressions such as surprise, fear, angry, disgust, sadness, and happiness. In the robot, each module communicates with the others via CAN communication protocol and according to the desired emotional expressions, the facial motions are generated by combining the motions of each actuator module. A prototype of the robot has been developed and several experiments have been conducted to validate its feasibility.

Assessment Model for Industrial Accidents Prevention Policy (산업재해 예방정책에 대한 평가모형)

  • Kim, Youngsun;Jo, Jinnam;Baik, Jaiwook
    • Journal of Applied Reliability
    • /
    • v.17 no.1
    • /
    • pp.38-49
    • /
    • 2017
  • Purpose: The purpose of this study is to introduce the assessment model for industrial accidents prevention policy. Methods: 10 years of industrial accidents data are explored through EDA approach. Case control study is tried in order to assess the effectiveness of the measures taken by Korea Safety and Health Agency, Civilian, and 'Ministry of Employment and Labor'. Propensity score matching is used to match the characteristics of the two groups compared, and then case control study is again conducted. Next, logistic and Poisson regressions are used to assess the risk factors. Results: According to case control study involvement of 'Korea Safety and Health Agency' and 'Ministry of Employment and Labor' were not effective, but Civilian was. Propensity score matching leads to the same conclusion. Poisson regression reveals the impact of the risk factors on the industrial accidents. Industrial accidents occur more often as the number of employees grows. Mining, farming, fishing, 'transportation storage and telecommunication' and forestry have a higher level of industrial accidents but service industry has a lower level. It is odd that more involvement of Korea Safety and Health Agency, Civilian, and Ministry of Employment and Labor means more industrial accidents. Conclusion: 'Korea Safety and Health Agency', Civilian, and 'Ministry of Employment and Labor' seem to visit those industries with more industrial accidents.

Research on the Characteristics of Science Subject Matter Knowledge (SMK) and Pedagogical Content Knowledge (PCK) of Primary School Teachers in Classroom Teaching

  • Kwak, Youngsun
    • Journal of the Korean earth science society
    • /
    • v.38 no.5
    • /
    • pp.367-377
    • /
    • 2017
  • The purpose of this research is to investigate characteristics of science content knowledge and pedagogical content knowledge shown in the primary school science classes. Through analysis of classroom teaching, explore the features and differences between primary and secondary school science PCK. Using open-ended interviews with the teachers and group discussions on a regular basis to analyze and compare classes of five primary school teachers, the relationship between CK and PCK. Regardless of the school level the teacher's PCK and professionalism is required with varying focus and emphasis. The features of the primary school teacher's PCK are as follows: Firstly, elementary teach secondary teach content, teachers value pedagogical knowledge (PK) content knowledge (CK). The primary school PCK requires more of understanding of students and teaching methods that to subject areas. PCK be without content knowledge, and the teacher's PCK is subject-specific In addition to the characteristics of PCK in the primary school science teaching, ways to set up professional exchange or collaboration between primary and secondary teachers, and to provide supplementary in-service training focused on content knowledge for primary school teachers.

Expressional Characteristics of Retro Image Shown on Wedding Dresses (웨딩드레스에 나타난 레트로 이미지의 표현 특성)

  • Gai, Shunan;Yoo, Youngsun
    • Journal of the Korean Society of Costume
    • /
    • v.66 no.2
    • /
    • pp.103-116
    • /
    • 2016
  • This study intends to discover characteristics and methods of retro image wedding dresses by analyzing prior studies about retro characteristics. The characteristics of retro image wedding dresses are as follows: 'Recreative Retro', Trend revival Retro', 'Nostalgic Retro' and 'Remixed Retro'. The expressional characteristics and methods of each character are as follows. The 'Recreated Retro' has been recreated in the wedding dresses worn by celebrities, actresses' wedding dresses in movies, and also in the famous designer's high end wedding dresses. These dresses do not merely duplicate the originals, but also reflect images, which were reproduced by combining modern technology. The 'Trend revival Retro' emerged as a combination of past fashion styles and new trends. It seems to stimulate the customers' reminiscence of past fashion trends and create unique designs through expressing the metaphor or the adaptation of past fashion styles. The 'Nostalgic Retro' started from the discovery of emotional values for something old or the inclination to be attracted to old styles. It has been expressed through design concepts with natural themes. The 'Remixed Retro' is from recombination of Retro elements. It is shown as a new interpretative code which explains how current time blends with different times.

Design of an NFC Baseband Modem for Software Overhead Minimization (소프트웨어 비용을 최소화하는 NFC 기저대 모뎀 설계)

  • Jun, Jaeyung;Kim, Seon Wook;Han, Youngsun
    • Journal of Korea Multimedia Society
    • /
    • v.18 no.12
    • /
    • pp.1547-1554
    • /
    • 2015
  • Because there are numerous near field communication (NFC) technical standards and each standard has an independent communication protocol, an NFC software for controlling the protocols are significantly complicated. Especially, the anticollision algorithm for establishing the initial communication connection is classified into bit-oriented or time slot method according to the technical standards. Moreover, the anticollision algorithm is generally manipulated in software because of its complexity. In addition, since one host processor is shared by multiple modems in a connectivity SoC, embedding several communication modems with an NFC modem, the spare computing resources can be utilized for other modems by reducing the software cost to control the NFC modem. In this paper, we propose new design methods of the NFC modem for supporting anticollision, framing and bit rate detection in the hardware to reduce the software overhead. Therefore, the utilization of the NFC technology is enhanced in the connectivity SoC by minimizing the cost of software.

Thermal Infrared Image Analysis for Breast Cancer Detection

  • Min, Sedong;Heo, Jiyoung;Kong, Youngsun;Nam, Yunyoung;Ley, Preap;Jung, Bong-Keun;Oh, Dongik;Shin, Wonhan
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.11 no.2
    • /
    • pp.1134-1147
    • /
    • 2017
  • With the rise in popularity of photographic and video cameras, an increasing number of fields are now using thermal imaging cameras. One such application is in the diagnosis of breast cancer, as thermal imaging provides a low-cost and noninvasive method. Thermal imaging is particularly safe for pregnant women, and those with large, dense, or sensitive breasts. In addition, excessive doses of radiation, which may be used in traditional methods of breast cancer detection, can increase the risk of cancer. This paper presents one method of breast cancer detection. Breast images were taken using a thermal camera, with preliminary experiments conducted on Cambodian women. Then the experimental results were analyzed and compared using Shannon entropy and logistic regression.