• Title/Summary/Keyword: 도래 시간

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Environmental factors affecting roost use of shorebirds in the southern Kanghwa Island, Republic of Korea (강화도 남단에 도래하는 도요새들의 해안 내륙 휴식지 이용과 이들의 이용에 영향을 미치는 환경요인들)

  • Kim, Kwan Mok;Moon, Young Min;Yoo, Jeong Chil
    • Journal of Wetlands Research
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    • v.15 no.2
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    • pp.251-264
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    • 2013
  • There are some factors affecting the shorebirds in selecting a coastal inland roost site where they have to stay during the high tide when the entire intertidal zone is covered with water. We investigated eight species (Eastern Curlews Numenius madagascariensis, Green Shanks Tringa nebularia, Bar-tailed Godwits Limosa lapponica, Grey Plovers Pluvialis squatarola, Dunlins Calidris alpine, Whimbrels Numenius phaeopus, Eurasian Curlews Numenius arquata and Terek Sandpipers Xenus cinereus) to identify the spatial and temporal variability in coastal inland roost use in the area and the factors influencing the use. We considered the area and length of the standing water in the roost site, temperature, wind speed, the time of migration and the intensity of disturbance. As a result, number of individuals and type of species using the roost site varied across spatial and temporal scales. And the factors affecting the roost use was species-specific. The roost site of the study area was a closed shrimp farm however, it has been converted to a Salicornia herbacea, a salt marsh plant, farm recently. In a situation where coastal inland roost site is needed, we hereby describe a resolution for the juxtaposition of shorebirds and farming.

A Study on Revaluation of copy theory in Representational Gaps Extinction of CGI (CGI(Computer-Generated Imagery)의 재현적 간극 소멸에서 보여지는 모사이론의 재평가에 관한 연구)

  • Chung, Kue-Hyung
    • Cartoon and Animation Studies
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    • s.29
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    • pp.103-128
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    • 2012
  • Study about existence of illusion which human beings feel from imitated image based reality have been continuing by copy theory and conventionalism for a long time. Traditional copy theory which had controlled representation theory from plato have explained illusion by similarity of image and representation objects. According to copy theory, image is natural sign unlike language but the late in the 20th century, conventionalism from N, Goodman insists they are not any special similarity between image and representation objects. They insist image and conventional sign just as language. These opposit theory rearranged conventionalism by the entrance on the cognitive science. The copy theory couldn't explain the problem of representational gap between reality and duplication, but photo media makes new paradigm about theory of the illusion. The problem of representational gap was disappeared by CGI images on the base of digital media. We are exposed exquisite duplication for a example, movie, advertisement, printings. Sometimes duplications are more real than the original works. Digital is a non-material object by 0 and 1. Specially real lighting skill and mechanism are copied perfectly by photon mapping skills and the duplications are produced more real than the original works. By disappearance of representational gap, we need new theory model for explaining of digital illusion and copy theory can be the key.

Analysis of Vibration Characteristics for a Molded Dry-type Potential Transformer (몰드형 건식 계기용 변압기 진동 특성 분석)

  • Kim, Moosun;Jang, Dong Uk;Kim, Seung Mo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.3
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    • pp.209-214
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    • 2017
  • Most of the present potential transformers of train vehicles are of the oil-type filled with insulating oil and are susceptible to problems such as explosion due to the increase in the internal pressure during train operation and poor reliability near the end of their life cycle. As a solution to this problem, it is necessary to develop a molded dry-type potential transformer with excellent pressure-resistance performance using insulating resin. In order to localize the product, the Korea Railroad Research Institute has been developing a molded dry-type potential transformer. As part of this research, it is necessary to analyze the vibration characteristics of the developed product and to check the transformer performance in a vibration environment. In this study, a resonance test and simulated long-term life test of the developed product were conducted according to the KS R 9144 and IEC 61373 standards, respectively, which are vibration test methods for railway vehicle parts. Their natural frequencies were analyzed by comparing the results of the numerical modal analysis and resonance test, in order to confirm their adherence to the standards. Also, the performance test after the simulated long-term life test confirmed that the operation of the developed transformer was not problematic even in a long-time vibration environment.

A Study on Computational Thinking based Test-Driven Problem Solving Learning Model (컴퓨팅 사고력 기반 테스트 중심 문제해결 학습 모형 연구)

  • Kim, Young-Jik;Kim, Seong-Sik
    • The Journal of Korean Association of Computer Education
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    • v.22 no.6
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    • pp.43-55
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    • 2019
  • In the Fourth Industrial Revolution, a super-intelligent and super-connected society has arrived. Software is an important part of the core technologies of the Fourth Industrial Revolution. The ability to solve problems through software requires software education in that it is a core competency that everyone should have. Software education aims to improve Computational Thinking, which is the ability to solve problems through programming. Until now, most problem-solving programming learning models follow the traditional method of development: Waterfall model (Analysis-Design-Development-Test). In this model, if there is a problem in the preceding step, That could be found in the test phase. This takes a considerable amount of time and effort to find a solution to the problem and can be a burden on the programming learning. In this study, we proposed a Test-Driven Problem-Solving learning model using TDD (Test Driven Development) as Agile development method, and reviewed the appropriateness of the model through experts review. The verification results of the model showed positive evaluation results. In particular, the learning phase configuration of the model, helping in programming learning, helping of Computational Thinking improvement showed high rating, it is determined that there will be positive effects on Computational Thinking improvement through problem-solving programming learning when applying future learning.

A Study on the Application of Spatial Big Data from Social Networking Service for the Operation of Activity-Based Traffic Model (활동기반 교통모형 분석자료 구축을 위한 소셜네트워크 공간빅데이터 활용방안 연구)

  • Kim, Seung-Hyun;Kim, Joo-Young;Lee, Seung-Jae
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.15 no.4
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    • pp.44-53
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    • 2016
  • The era of Big Data has come and the importance of Big Data has been rapidly growing. The part of transportation, the Four-Step Travel Demand Model(FSTDM), a traditional Trip-Based Model(TBM) reaches its limit. In recent years, a traffic demand forecasting method using the Activity-Based Model(ABM) emerged as a new paradigm. Given that transportation means the spatial movement of people and goods in a certain period of time, transportation could be very closely associated with spatial data. So, I mined Spatial Big Data from SNS. After that, I analyzed the character of these data from SNS and test the reliability of the data through compared with the attributes of TBM. Finally, I built a database from SNS for the operation of ABM and manipulate an ABM simulator, then I consider the result. Through this research, I was successfully able to create a spatial database from SNS and I found possibilities to overcome technical limitations on using Spatial Big Data in the transportation planning process. Moreover, it was an opportunity to seek ways of further research development.

System Diagnosis and MEMS Driving Circuits Design using Low Power Sensors (저 전력 센서를 이용한 MEMS 회로의 구현과 시스템 효율의 진단)

  • Kim, Tae-Wan;Ko, Soo-Eun;Jabbar, Hamid;Lee, Jong-Min;Choi, Sung-Soo;Lee, Jang-Ho;Jeong, Tai-Kyeong
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.45 no.1
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    • pp.41-49
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    • 2008
  • Many machineries and equipments are being changing to various and complicated by development of recent technology and arrival of convergence age in distant future. These various and complicate equipments need more precise outcomes and low-power consumption sensors to get close and exact results. In this paper, we proposed fault tolerance and feedback theorem for sensor network and MEMS circuit which has a benefit of energy efficiency through wireless sensor network. The system is provided with independent sensor communication if possible as unused action, using idle condition of system and is proposed the least number of circuits. These technologies compared system efficiency after examining product of each Moving Distance by developed sensor which gives effects to execution of system witch is reduced things like control of management side and requirement for hardware, time, and interaction problems. This system is designed for practical application; however, it can be applied to a normal life and production environment such as "Ubiquitous City", "Factory Automata ion Process", and "Real-time Operating System", etc.

An Improvement for Location Accuracy Algorithm of Moving Indoor Objects (실내 이동 객체의 위치 정확도 개선을 위한 알고리즘)

  • Kim, Mi-Kyeong;Jeon, Hyeon-Sig;Yeom, Jin-Young;Park, Hyun-Ju
    • Journal of Internet Computing and Services
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    • v.11 no.2
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    • pp.61-72
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    • 2010
  • This paper addresses the problem of moving object localization using Ultra-Wide-Band(UWB) range measurement and the method of location accuracy improvement of the indoor moving object. Unlike outdoor environment, it is difficult to track moving object position due to various noises in indoor. UWB is a radio technology that has attention for localization applications recently. UWB's ranging technique offer the cm accuracy. Its capabilities for data transmission, range accurate estimation and material penetration are suitable technology for indoor positioning application. This paper propose a positioning algorithm of an moving object using UWB ranging technique and particle filter. Existing positioning algorithms eliminate estimation errors and bias after location estimation of mobile object. But in this paper, the proposed algorithm is that eliminate predictable UWB range distance error first and then estimate the moving object's position. This paper shows that the proposed positioning algorithm is more accurate than existing location algorithms through experiments. In this study, the position of moving object is estimated after the triangulation and eliminating the bias and the ranging error from estimation range between three fixed known anchors and a mobile object using UWB. Finally, a particle filter is used to improve on accuracy of mobile object positioning. The results of experiment show that the proposed localization scheme is more precise under the indoor.

Empirical Study on Factors Influencing the Value of Mobile Advertising: From the Perspective of Information Value (정보 가치 관점에서 바라본 모바일 광고 가치의 설명 요인에 관한 실증적 연구)

  • Park, Chul-Woo;Ahn, Joong-Ho;Jahng, Jung-Joo;Kim, Eun-Jin
    • Information Systems Review
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    • v.8 no.2
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    • pp.29-49
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    • 2006
  • The introduction of the Digital Economy has formed a new market producing and trading information. Depending on the current contexts, each user evaluates identical information differently. It is difficult, even though important, to create and deliver the information customized to individual users by using some factors as time, location, and their personal characteristics. Information value, therefore, could be influenced by the capability of information systems to delivery useful information based on individual contexts to the right user immediately at the right time. From this point of view, we argue mobile systems which are able to be aware of individual contexts and deliver contextual information in real time can improve information value easily than other systems can. This research presents the results of an empirical test about antecedents to mobile advertising value. Though context relevance doesn't influence directly mobile advertising value, it plays an important role enhancing information usefulness which has great influence on mobile advertising value. Moreover, to supply information connected with users' context overcomes the effect of irritation. Lastly, entertainment can improve mobile advertising value as satisfying user's hedonic desire beyond the information source supporting decision making.

Using GIS to Estimate Estuarine Wetlands in Three Major Estuaries and to Quantify Wetland Changes over the Last Century (GIS를 활용한 하구의 습지추정 및 변화추이 분석에 관한 연구)

  • Rho, Paikho;Lee, Chang-Hee
    • Journal of Wetlands Research
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    • v.9 no.2
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    • pp.21-31
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    • 2007
  • Estuarine wetland, where freshwater meets saltwater, is a transitional ecosystem that is valuable ecologically for a variety of reasons, such as feeding and breeding sites for birds, fish, and wildlife. However, research on the spatial distribution and temporal dynamics of estuarine wetlands in Korea is rare. As a fundamental basis for wetland conservation, this study quantified the wetlands in three major estuaries, and evaluated the temporal dynamics of the wetlands since the 1910s. In particular, this study classified the wetland types into mud flat, sand, and emergent-plant types, and estimated the change of each wetland type, using topographic maps produced in the 1910s, 1970s, and 2000s. The wetlands in both the Han and Youngsan River estuaries have declined since the 1910s, but the rate of wetland decline was relatively low before the 1970s, compared to that since the 1970s. The impact of human activities, such as the Youngsan Watershed Comprehensive Development Project and the construction of estuary barrages, has disrupted the estuary cycles and destroyed huge amounts of wetland in the Youngsan estuary. By contrast, estuarine wetlands have been preserved in the small Gahwa estuary, and provide a variety of habitats for plants and wildlife. A special management strategy for wetlands should be established as soon as possible.

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Design and fabrication of GaAs MMIC high power amplfier and microstrip combiner for IMT-2000 handset (IMT-2000 고출력 전력전폭기의 GaAs MMIC화 및 전송결합기 설계 구현에 관한 연구)

  • 정명남;이윤현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.11A
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    • pp.1661-1671
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    • 2000
  • 본 고에서는 한국통신(Korea Telecom) IMT-2000 시험시스템(이하: Trial system 라고 함) 단말기용 전력증폭단으로 적용하기 위한 다단구동증폭기 및 전력증폭기를 GaAs MMIC로 설계 구현하는 기술을 제시하였다. 설계된 구동증폭기는 3단으로구성하여 RF(Radia Frequency) 송신신호(1955$\pm$70MHz)대역에서 2단 (중간단)의 이득 조정범위가 40 dB이상이 될 수 있도록 능동부품인 MESFET를 Cascade 형으로 구성하고 MESFET의 게이트(gate)에 조정전압을 인가하는 증폭기를 설계하여 GaAs MMIC화 1 침(크기4$\times$5 mm)으로 제작하였다. 아울러, 본 논문에서는 제시한 구동증폭기는 동작주파수 대역폭 범위기 3.5배이고 출력전력은 15dBmm 이며, 출력전력이득이 25~27dB이고 반사계수는 -15~20dB이며 이득평탄도 3dB(동작주파수 대역폭내)로써 Trial system용 단말기의 최종단인 전력증폭단의 출력단 특성을 효과적으로 나타내었다. 그리고, 전력 증폭기는 2개의 입력단에서 출력되는 신호를 분배하는 전력분배기와 병렬구조인 4개의 증폭단에서 출력되는 출력신호를 외부에서 접속하는 전력결합기를 접소하여 구성하였으며 RF(Radio Frequency) 주파수(1955 $\pm$70NHz)에서 대역폭을 4배로 설계하여 광대역인 대역폭을 구현하였고 출력전력은 570mW이며, 출력부가효율(PAE; Power Added Efficency)가 -15$\pm$20dB이고, 이득 평탄도(Gain flatness)는 동작주파수 대역내에서 0.5dB이며 입출력 전압정재파비(Input & Output VSWR)가 13이하인 고출력 전력증포기를 GaAs MMIC화 1칩 (크기; 3$\times$4mm)으로 제작하였다.의 다양성이나 편리성으로 변화하는 것이 국적을 바꾸는 것보다 어려운 시 대가 멀지 않은 미래에 도래할 것이다. 신세기 통신 과 SK 텔레콤에는 현재 1,300만명이 넘 는 고객이 있으며. 이들 고객은 어 이상 음성통화 중심의 이동전화 고객이 아니라 신세기 통신과 SK텔레콤이 함께 구축해 나갈 거대란 무선 네트워크 사회에서 정보화 시대를 살아 갈 회원들이다. '컨텐츠의 시대'가 개막되는 것이며, 신세기통신과 SK텔레콤은 선의의 경쟁 과 협력을 통해 이동인터넷 서비스의 컨텐츠를 개발해 나가게 될 것이다. 3배가 높았다. 효소 활성에 필수적인 물의 양에 따른 DIAION WA30의 라세미화 효율에 관하여 실험한 결과, 물의 양이 증가할수록 그 효율은 감소하였다. DIAION WA30을 라세미화 촉매로 사용하여 아이소옥탄 내에서 라세믹 나프록센 2,2,2-트리플로로에틸 씨오에스터의 효소적 DKR 반응을 수행해 보았다. 그 결과 DIAION WA30을 사용하지 않은 경우에 비해 반응 전환율과 생성물의 광학 순도는 급격히 향상되었다. 전통적 광학분할 반응의 최대 50%라는 전환율의 제한이 본 연구에서 찾은 DIAION WA30을 첨가함으로써 성공적으로 극복되었다. 또한 고체 염기촉매인 DIAION WA30의 사용은 라세미화 촉매의 회수 및 재사용이 가능하게 해준다.해준다.다. TN5 세포주를 0.2 L 규모 (1 L spinner flask)oJl에서 세포간의 응집현상 없이 부유배양에 적응,배양시킨 후 세포성장 시기에 따른 발현을 조사한 결과 1 MOI의 감염조건 하에서는 $0.6\times10^6$cell/mL의 early exponential시기의 세포밀도에서 72시간 배양하였을 대 최대 발현양을 나타내었다. 나타내었다. $\beta$4 integrin의 표현이 침투 능력을 높이는 역할을 하나 이때에는 laminin과 같은 리간드와의 특이

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