• Title/Summary/Keyword: 공기 추출

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Derivation of Relation between Variation of Gradients of Antenna Tower of GNSS Permanent Observatories Depending on Diurnal Variation of External Air Temperature and Movement of Phase Center of Antenna (바깥 공기 온도의 일변화에 의한 GNSS 상시관측소 안테나탑 기울기 변화와 안테나 위상중심 위치의 운동 사이의 관계 추출)

  • Lim, Mu-Taek;Kwak, Byung-Wook;Park, Yeong-Sue;Rim, Hyoung-Rae
    • Geophysics and Geophysical Exploration
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    • v.12 no.2
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    • pp.208-214
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    • 2009
  • Using the GNSS data and tilt-meter data of Boeun (BOEN) and Goesan (GSAN) GNSS stations, we have calculated the differential distance vector variation with the calculation time span set to 1 hour and 3 hour and differential tilt vector variation along time and derived an indicator of similarity between the two variations along time. The similarity such calculated is rather lower than high. But as the existence of a circular type movement of the antenna's phase center's location due to the tilt's variation of the antenna tower because of the sunlight's diurnal change is certain, we recommend to take such diurnal variation of antenna's location into consideration when the correction error in DGNSS or the measured data at reference stations in VRS (Virtual Reference System) is broadcast.

금 나노패턴을 이용한 서브파장구조를 가진 광대역 무반사 글래스의 제작 및 특성

  • Im, Jeong-U;Lee, Su-Hyeon;Guan, Xiang-Yu;Kim, Jeong-Tae;Jeong, Gwan-Su;Yu, Jae-Su
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.279.1-279.1
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    • 2014
  • 글래스(glass), 폴리머 또는 쿼츠와 같은 투명기판은 렌즈, 디스플레이, 광검출기, 광센서, 발광다이오드 및 태양전지와 같은 광 및 광전소자 분야에서 널리 사용되고 있다. 이러한 소자들의 경우, 광추출 또는 광흡수 효율을 향상시키는 것이 매우 중요하다. 그러나 투명기판의 경우, 약 1.5의 굴절율로 인해 표면에서 4% 반사가 발생되는데, 이러한 광학적 손실은 소자의 성능을 저하시키는 원인이 된다. 따라서, 글래스와 공기 경계면에서 발생되는 광손실을 줄이기 위한 효율적인 무반사 코팅이 필요하다. 최근, 우수한 내구성 뿐만 아니라, 광대역 파장 및 다방향성에서 무반사 특성을 보이는 서브파장 주기를 갖는 나노구조(subwavelength structures)의 형성 및 제작 공정에 관한 연구가 보고되고 있다. 이러한 나노구조는 경사 굴절율 분포를 가지는 유효 매질을 형성하기 때문에 투명기판 표면에서의 Fresnel 반사로 인한 광손실을 줄일 수 있다. 또한, 무반사 서브파장구조를 형성하기 위한 패터닝 방법으로, 간단/저렴하고 대면적 제작이 용이한 열적 응집 공정을 이용한 자가정렬된 금속 나노입자 형성 기술이 널리 사용되고 있다. 따라서 본 실험에서는 열적 응집현상에 의해 형성된 비주기적 금 나노입자 식각 마스크 패턴 및 유도결합 플라즈마 장비를 이용하여 글래스 기판 위에 무반사 서브파장 나노구조를 제작하였다. 금 나노패턴 및 제작된 글래스 서브파장 나노구조의 식각 프로파일은 주사전자현미경을 사용하여 관찰하였으며, UV-Vis-NIR 스펙트로미터를 사용하여 빛의 투과율을 측정하였다. 또한, 제작된 샘플들에 대해서, 표면 접촉각 측정 장비를 이용하여 표면 wettability를 조사하였다.

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A Study on Installed Performance Analysis Modelling for a Helicopter Propulsion System Considering Intake Loss (흡입구 손실을 고려한 헬리콥터 추진시스템의 장착성능 해석 모델에 관한 연구)

  • Kong, Chang-Duk;Kho, Seong-Hee;Ki, Ja-Young;Jun, Yong-Min;Ahn, Lee-Ki
    • Journal of the Korean Society of Propulsion Engineers
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    • v.12 no.1
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    • pp.51-56
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    • 2008
  • In this work the realistic install performance analysis of a helicopter was performed together with power extraction enabling to operate auxiliary system as well as intake pressure loss, loss due to bleed air, etc. which must be considered in practical propulsion system's performance modelling to be installed to the airframe. The pressure loss occurring in intake was estimated from the intake performance map with relationships of Mach Number and pressure loss. In order to evaluate the proposed installed performance model, the experimental data for comparison must be needed when mounted in propulsion system. However because of lack of accessibility to such real data at the moment, the alternative way was made through comparison that the analysis results by the proposed model were compared with a wellknown commercial program GASTURB's analysis results. The validity of the proposed installed performance model was consequently confirmed because its average deferences from the GASTURB's results were within 0.5%.

Reliable Smoke Detection using Static and Dynamic Textures of Smoke Images (연기 영상의 정적 및 동적 텍스처를 이용한 강인한 연기 검출)

  • Kim, Jae-Min
    • The Journal of the Korea Contents Association
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    • v.12 no.2
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    • pp.10-18
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    • 2012
  • Automatic smoke detection systems using a surveillance camera requires a reliable smoke detection method. When an image sequence is captured from smoke spreading over in the air, not only has each smoke image frame a special texture, called static texture, but the difference between two smoke image frames also has a peculiar texture, called dynamic texture. Even though an object has a static texture similar to that of the smoke, its dynamic texture cannot be similar to that of the smoke if its movement differs from the diffraction action of the smoke. This paper presents a reliable smoke detection method using these two textures. The proposed method first detects change regions using accumulated frame difference, and then picks out smoke regions using Haralick features extracted from two textures.

A Study on 4P's of Developing Food Service Products - Focused on Gwangju, Jeonnam Area - (외식 상품 개발의 4P's에 관한 연구 - 광주, 전남 지역 중심으로 -)

  • Lee, Sun-Ho;Kim, Hee-Kee;Kong, Ki-Yul;Jeon, Kyung-Chul
    • Culinary science and hospitality research
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    • v.16 no.1
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    • pp.269-279
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    • 2010
  • This study investigates 4P's of developing food service products(Focused on Gwangju, Jeonnam area) and intends to set the direction for the relations between product, price, promotion, place and customer satisfaction and customer occupation. Statistical techniques employed includes reliability analysis and regression analysis. The study is based on the 220-questionnaire-survey conducted from July 6 to July 20, 2009 to five foodservice companies in Gwangju. The data collected of this study were analyzed with the frequency analysis, reliability analysis, and regression analysis using the SPSS 12.0 package program. The findings of this study are as follows. Firstly, there are significant product, price, promotion and place factors that affect customer satisfaction. Secondly, there are significant product, price, promotion and place factors that affect customer occupation. Thus, food service management needs to apply product, price, promotion and place strategies aggressively.

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A Study on the Design Technique of Linear Actuator by using CAE System (전산응용설계 시스템을 이용한 리니어 액츄에이터의 설계기법 고찰)

  • 이권헌;조제황;조경재;오금곤;김영동
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.11 no.1
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    • pp.106-113
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    • 1997
  • In this paper, we introduce the design method using CAE(Computer Aided Engineering) which is profitable in the compatibility and standardization of the developed product and in the reduction of construction time and price to develop and design a machine equipment. Particularly, we select the standard model to design ot develop from the large machinery to the super precision one, extract the peculiar characters of the model by the close analysis of the physical and technical part, can predict the previous result of experimental characteristics on objective dimensions through the analogical mathematical analysis, and can induce the design model demanded by user investigating optimal data in advance. We present the analogical algorithms and process method of design factors and restriction factors in the systematization design with computer. Then we analyze step functions for each systematization equipment and induce the process of technical data with actuator model.

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Analysis of Vocal Cord Function by Humidity Change Based on Voice Signal Analysis (음성신호 분석 기반의 습도 변화에 따른 성대 기능 분석)

  • Kim, Bong-Hyun;Cho, Dong-Uk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37A no.9
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    • pp.792-798
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    • 2012
  • Network Quotient, an important figure in modern society, the intelligibility of speech as a conversation partner to maximize pulling up feeling of liking it as much as possible has become an important issue. The humidity of air in the intelligibility of speech have many influences. Therefore, in this paper, we carried out experiment to apply voice signal analysis techniques which to analyze influenced vocal cords in 30%, 50% and 80%, maintaining a constant humidity of the environment. With this in mind, we carried out experiments on intensity and pitch of voice signal on twenty male 20s in maintaining a constant humidity 30%, 50% and 80% of humidity. Finally, we carried out study to draw a significance through statistical analysis measuring characteristic parameter of vocal cord function to change of humidity.

Improving the Job Success Rate through Analysis of User Logs in HPC (HPC 환경에서 사용자 로그 분석을 통한 작업 성공률 개선)

  • Yoon, JunWeon;Hong, TaeYoung;Kong, Ki-Sik;Park, ChanYeol
    • Journal of Digital Contents Society
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    • v.16 no.5
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    • pp.691-697
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    • 2015
  • Supercomputers are used for many different areas including new product design of industries as well as state-of-the-art science and technology for large amount of computational needs. Tachyon is a 4th supercomputer built at KISTI that is a high-performance parallel computing system with 3,200 computing nodes and infrastructures. This system is currently about 10,000 users and over 170 organizations are used, the number of jobs they are performing work in batch type form through a scheduler. Also, this system logs lots of job scripts, execution environment, library, job status from the job submit to end. In this paper, we analyzed batch jobs information from Sun Grid Engine, that use as a scheduler in Tachyon system, and job executed information in Tachyon System. In particular, we distinguished the fail jobs from the all tasks that users perform and we analyzed the cause of failure. Among them, we can extracted some of jobs that can be regarded as normal jobs through the improvement in those works logged as all of fail jobs.

Material Planning Model for Multi-Project Management in Medium-sized Construction Companies (중견건설업체의 다중현장관리를 위한 자재조달계획 지원 모델)

  • Jung Sung-Lim;Han Ju-Yeon;Kim Kyung-Rai;Shin Dong-Woo
    • Korean Journal of Construction Engineering and Management
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    • v.5 no.2 s.18
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    • pp.106-114
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    • 2004
  • As the scale of construction work is enlarged, complicated and diversified, much construction information from the large number of construction sites is generated and reported to the head office. To control much information generated in construction sites simultaneously, the necessity of supporting system which could extract necessary information is increased. However, comparing with those of large companies, medium-sized companies's organization of head office and management system are weak. So it's difficult to manage multi-projects. Among these site managements, resource management is an important management area. But, resource planning is based on experience and judgement and has not associated with schedule information. So when schedule is changed, the plan must be amended manually. This study investigates material-planning model for multi-project management which is connected with daily report system and scheduling software.

High Production of L-Threonine using Controlled Feeding of L-Methionine and Phosphate by Escherichia coli Mutant (L-Methionine과 Phosphate의 제한 공급에 의한 Escherichia coli MT201로부터의 고농도 L-Threonine 생산)

  • 이만효;이홍원;김병진;김천석;정준기;황용일
    • Microbiology and Biotechnology Letters
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    • v.32 no.2
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    • pp.149-153
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    • 2004
  • L-Threonine fermentation process was constructed on batch and fed-batch culture by using Escherichia coli MT201. The production type of L-threonine was observed as growth-associated production in batch culture. In fed-batch culture studying optimal concentration of yeast extract in feeding media, when 600 g/l of glucose and 60 g/l of yeast extract were added in feeding media, 87 g/$\ell$ of L-threonine was produced. To improve cell growth and L-threonine production, the culture of high cell density was performed in fed-batch culture with oxygen enriched air and feeding media containing L-methionine and phosphate. Under the conditions, we could achieve the highest L-threonine production of98 g/$\ell$ at 60 h. The highest productivity of L-threonine was about 3.85 g/$\ell$/h.