• Title/Summary/Keyword: 누적효과

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A Study of the Effects of Use upon RGP Contact Lens Surface Ultrastructure (RGP Contact Lens 표면 미세구조에 대한 사용 효과의 연구)

  • Kim, Douk-Hoon;Sung, A-Young;Crossman, Stanley
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.1
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    • pp.71-75
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    • 2006
  • The aim of this study was to analyze the surface ultrastructure of RGP contact lenses post-use The RGP contact lenses, to investigate, were selected after one month, six months and one year of wear by the subjects. The anterior and posterior surfaces of these RGP contact lenses were inspected by a scanning electron microscope. The results were the following: 1. After one month of RGP contact lens use the anterior and posterior surfaces appeared clean and clear as originally. 2. After six months the anterior surface had several scars, dips, cracks and scratches. Upon the posterior surface appeared several foreign bodies and microorganisms. 3. After one year there was large scale damage and many foreign bodies were observed. Therefore, extended use of RGP contact lenses has shown increasing physical damage and extensive foreign body accumulation upon the ultrastructure of the lens surface.

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Personal Media as Cultural Intermediaries, YouTube Channel (디지털 문화매개자로서 1인 미디어, 유튜브 채널 <영국남자>)

  • Kim, Junghyun;Kim, Bo-Young
    • The Journal of the Korea Contents Association
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    • v.18 no.6
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    • pp.50-62
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    • 2018
  • This study is to ascertain the meaning of personal media as cultural intermediaries in the cultural diffusion, acceptance, and intermediation for the production and consumption of cultural contents. We examined the case of personal media, , which is one of popular YouTube channel in Korea and analyzed fifty most viewed videos in last two years based on four perspectives of digital cultural intermediaries: forms, expression methods, linguistic features, and evaluations. As expected, results demonstrate that shows characteristics of digital intermediary: diverse subjects without fixed rules, a variety of multimedia effects, colloquial style including neologism and multilingual, and users' high preferences caused by creator's sincerity. Our findings and limitations can serve directions of further empirical researches.

A Study on the Analysis of Service-linkage between the u-City and ITS (u-City와 ITS의 서비스 연관성 분석에 관한 연구)

  • Song, Yang-Bin;Kim, Gyeong-Seok;Seo, Min-So;Lee, Sun-Ha
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.1
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    • pp.101-114
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    • 2008
  • Ubiquitous City (u-City) and Intelligent Transport System (ITS) provide services, which are different from each other yet have close relation to each other partially. Thus, since a redundancy issue occurs or it is difficult to efficiently provide services depending on the relation degree, it is required to analyze the relation of services between the two systems and to elicit a priority. A table of relation among the services was created and the relation degree was analyzed by performing a survey for experts. As a result of calculating the total marks by accumulating and summing up the survey results, the incident management service and u-accident/calamity and disaster service of the ITS had the lowest value. The project priority was as follows: The basic principle of the project was that services with high relation degrees shall be worked on first. The services were categorized in each step and packaging the services could result in the synergy effect. This study is significant since it analyzed the relation degree between u-City and ITS and proposed schemes for efficiently working on the project by eliciting the priority of the services based on the analysis results.

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Principal Component Transformation of the Satellite Image Data and Principal-Components-Based Image Classification (위성 영상데이터의 주성분변환 및 주성분 기반 영상분류)

  • Seo, Yong-Su
    • Journal of the Korean Association of Geographic Information Studies
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    • v.7 no.4
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    • pp.24-33
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    • 2004
  • Advances in remote sensing technologies are resulting in the rapid increase of the number of spectral channels, and thus, growing data volumes. This creates a need for developing faster techniques for processing such data. One application in which such fast processing is needed is the dimension reduction of the multispectral data. Principal component transformation is perhaps the mostpopular dimension reduction technique for multispectral data. In this paper, we discussed the processing procedures of principal component transformation. And we presented and discussed the results of the principal component transformation of the multispectral data. Moreover principal components image data are classified by the Maximum Likelihood method and Multilayer Perceptron method. In addition, the performances of two classification methods and data reduction effects are evaluated and analyzed based on the experimental results.

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PDA-Based Software Development for Forest Inventory Data (PDA기반의 산림자원조사용 소프트웨어 개발에 관한 연구)

  • Lee, Heonho;Lee, Dohyung;Suk, Sooil
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.690-695
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    • 2006
  • This study was carried out to develop a system for forest resources inventory using PDA. The Forest Inventory Software running on PDA was developed based on a Forest Resources Inventory Method by Korea Forestry Service and 4th National Forest Inventory Method. The forest inventory data stored in PDA contains sea level and GPS positioning data. Forest inventory input items are 34 tree species, 18 diameter class by each tree species, number of trees, tree height per each diameter class, thickness of bark, and annual growth of tree. Application test of the software with the forest workers shorted that, hours of forest works were remarkably reduced. It is possible to do forest inventory effectively using Forest Inventory Software developed by this study. Therefore, investigation and management expenses can be reduced and labor productivity will be improved.

A Study on the Development of an Experiential Exhibition Program for Children about Presidential Archives Based on the Experience Economy (4Es) (체험경제이론(4Es)을 적용한 대통령기록관 어린이 체험전시관 프로그램 개발에 관한 연구)

  • Song, Na-ra;Jang, Hyo-Jeong;Choi, Hyo-Young;Kim, Chong-Hyuck;Kim, Yong
    • Journal of Korean Society of Archives and Records Management
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    • v.16 no.1
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    • pp.9-40
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    • 2016
  • The space designated for kindergarten and elementary school students, who accounted for half of all users of the presidential archives, is now lacking, with the archives' programs focusing on exhibitions and field trips. With this, an experience exhibition is seen as the most effective way to communicate the value of presidential records and archives based on the theory of cognitive development. Therefore, this study proposes an experiential exhibition program for children about presidential archives based on the experience economy under theories that are recently getting attention. The Presidential Archives through the Experiential Exhibition program for children proposed by this study will become a place for the cultural communication of all generations.

Performance Analysis of Initial Cell Search in WCDMA System over Rayleigh Fading Channels (레일리 페이딩 채널에서 W-CDMA 시스템의 초기 셀 탐색 성능 해석)

  • Song, Moon-Kyou
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.4
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    • pp.1-10
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    • 2001
  • The 3-step cell search has been considered for fast acquisition of the scrambling code unique to a cell in the W -CDMA system. In this paper, the performance of the cell search scheme is analyzed in Rayleigh fading channels. And the system parameters for cell search scheme and the design parameters for the receivers are examined. The probabilities of detection, miss and false alarm for each step are derived in closed forms based on the statistics of CDMA noncoherent demodulator output. Through the analysis, the effect of threshold setting and post detection integration for each step is investigated, and the optimal values of the power allocation for the synchronization channels are also considered. The number of post-detection integrations for each step is a design parameter for the receiver, and the optimum values may depend on not only the power allocation for each channel related to the cell search, but the false alarm penalty time. It is shown that optimal values could be determined through the analysis. Also, the cumulative probability distribution of the average cell search time is obtained.

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A Study on the Monitoring Technique for Musculoskeletal Safety Management and Implementation of the System (근골격계 안전관리를 위한 모니터링 기법에 관한 연구 및 시스템 구현)

  • Shin, Yeong-Ju;Joo, Ha-Young;Yang, Jin-Hong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.3
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    • pp.267-276
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    • 2020
  • Manufacturing workers are easily exposed to the risk of musculoskeletal disorders caused by repetitive tasks in their working environment. This is due to problems with occupational characteristics that repeatedly use the body. However, the current lack of monitoring systems for monitoring and prevention has led to an increase in workers' exposure to risks each year. This paper presents how to solve these problems in real working environment by producing wearable devices using IMU sensors. After wearing a wearable type device, the user's movement is judged through data analysis by receiving the rotation value according to musculoskeletal movement. At this time, the risk is determined by measuring the number of rotations of the user by eliminating bias and eliminating cumulative error, acquiring sophisticated data, and analyzing it in the form of dynamic threshold values. Using the wearable device proposed in this paper, the effect of this method could be checked through a web page measuring the number of rotations for elbow musculoskeletal disorders.

Multi-Band RF Energy Harvesting System Using Buck-Boost DC-DC Converter (Buck-Boost DC-DC Converter를 이용한 다중 대역 RF 에너지 수집 시스템)

  • Cho, Choon Sik
    • Journal of Satellite, Information and Communications
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    • v.12 no.2
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    • pp.89-93
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    • 2017
  • This paper introduces an energy harvesting system that generates energy by collecting multi-band RF signals using buck-boost DC-DC converter. In an environment where the resistance of load using the collected electric energy is constantly changing, a buck-boost DC-DC converter is used in which the input resistance of the DC-DC converter does not change even if the load resistance changes. Since the frequency band of the input RF signal varies, the rectifier is designed for each band so that multiple bands can be processed, and a matching circuit is added to each band in front of the rectifier. For a rectifier to collect very small RF signals, a circuit is designed so that a constant voltage is obtained according to a very small input signal by devising a method of continuously accumulating the voltages collected and generated in each band. It is confirmed that the output efficiency can reach up to 20% even for the RF signal having the input of -20 dBm.

Biogas Production Effect by addition of Red Pepper Powder through Single Stage Anaerobic Co-Biogasification of Mechanically Pre-treated Food Waste and Primary Sewage Sludge Mixture (하수슬러지와 음식폐기물의 단상 혐기성 통합 소화 처리 시 고춧가루 함량 변화가 바이오 가스 생산에 미치는 영향)

  • Lee, Byung Sun
    • Resources Recycling
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    • v.26 no.1
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    • pp.59-68
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    • 2017
  • This study has been conducted to evaluate the effects of a single stage anaerobic co-biogasification of food waste and primary sewage sludge mixture (1 : 5 V/V%) according to mixing ratio (0% : CAP0, 0.5% : CAP0.5, 1%: CAP1.0) in red pepper powder, which was reported as the material anti-bacterial and anti-fungi, under mesophilic condition ($35^{\circ}C$). during 31 days. It showed that red pepper powder effected anaerobic bacteria, Especially, Hydrolytic bacteria and methanogenic bacteria was inhibited much more than Acetogenic bacteria with red pepper powder. at CAP0, Experimental cumulative methane yield (ECMY) and Experimental bio-energy production (EBEP) were 0.17 L $CH_4/g$ $VS_{fed}$ and 1,465 cal/g $VS_{fed}$ individually as the highest value during 31 days.