• Title/Summary/Keyword: 지가 변화

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A Study on the Telescopic Cascode Comparator in SET Situation (SET 상황에서 텔레스코픽 캐스코드 비교기에 관한 연구)

  • Jang, Jae-Seok;Chung, Jae-Pil;Park, Jung-Cheul
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.4
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    • pp.277-282
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    • 2020
  • This study was initiated to find a way to resolve electronic equipment as it could be affected by multiple environments. The effect of setting the exponential constant wave (iExp) in the telescopic cascade comparator to the SET (Single Event Transient) environment was tested. In this paper, the radio wave delay was measured at 0.46 ㎲ and the gain at 0.713 in the telescopic cascade comparator without setting the SET situation. FET T0 (M6) was measured to have a large spike at 11㎲ to 15㎲ in the telescopic cascade comparator entering the SET situation. FET T1 (M5) has shorted output signals from 10 ㎲ to 16 ㎲. FET T2 (M3) represented a shorted output signal, and FET T3 (M4) measured the output waveform in the form of a large spike waveform. The FET T4 (M1) and FET T5 (M2) are spiky signals. And at all FETs, the propagation delay was changed from 0.45㎲ to 0.54㎲. In summary, The FET element in the telescopic cascade comparator in SET situation was measured to be greatly affected.

A Study on the Vibration Phenomenon of 6 Bundle Boltless Spacer Damper (6도체 무볼트형 Spacer Damper의 진동현상에 관한 연구)

  • 김영달
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.3
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    • pp.110-118
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    • 2003
  • Spacer dampers maintain the constant gaps between each conductor in a bundle conductor-transmission line, and are installed at proper intervals to keep a line from all sorts of damages derived from the vibration energy caused by mechanical or electrical external factors. It is most important to embody a technology which considers difficulties of maintenance and repair, and has optimum elements in order to prevent accidents such as destruction by fire or the snapping of a wire by the effect of vibration phenomenon coming from transmission lint In the resent thesis, therefore, the analysis of vibratory characteristics of spacer damper is set up by analytical methods such as the analysis of conductor motion's governing equation, the equation of spacer damper's motion, spacer damper-fastened wire's motion in a span and the numerical analysis of finite difference method. Furthermore, the installation distance between spacer dampers was scrutinized by simulations of various vibration phenomena which change at any time as actual conditions do, and hereafter difference method. Furthermore, the installation distance between spacer dampers was scrutinized by simulations of various vibration phenomena which change at any time as actual conditions do, and hereafter we will be able to analyze all kinds of vibration phenomena coming from a boltless spacer damper with 6 bundle conductor for 765kV transmission line based on new analytical methods.

Proposal for a Custody and Federated Service Model for the Decentralized Identity (분산 ID 보관 및 연계 서비스 모델 제안)

  • Yeo, Kiho;Park, Keundug;Youm, Heung Youl
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.3
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    • pp.513-525
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    • 2020
  • Until today, the personal information of subjects has been centralized in many companies or institutions. However, in recent days, the paradigm has gradually changed in the direction that subjects control their personal information and persue their self-sovereignty. Globally, individual data sovereignty is strengthened by the European Union's General Data Protection Regulation(GDPR) and the US California Consumer Privacy Act(CCPA). In Korea, a few alliances consist of various companies are creating technology research and service application cases for decentralized ID service model. In this paper, the current decentralized ID service model and its limitations are studied, and a improved decentralized ID service model that can solve them is proposed. The proposed model has a function of securely storing decentralized ID to the third party and a linkage function that can be interoperated even if different decentralized ID services are generated. In addition, a more secure and convenient model by identifying the security threats of the proposed model and deriving the security requirements, is proposed. It is expected that the decentralized ID technology will be applied not only to the proof of people but also to the device ID authentication management of the IoT in the future.

Statistical Analyses on the Relationships between Red Tide Formation and Meteorological Factors in the Korean Coastal Waters (한국 연안의 적조형성과 기상인자간의 관계에 대한 통계적 해석)

  • 윤홍주;서영상;정종철;남광우
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.4
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    • pp.926-932
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    • 2004
  • This study deals with the statistical analyses on the relationship between the red tide formation and the meteorological factors in the Korean coastal waters. From 1995 to 2002, the red tide was observed every year and the number of occurrences increased as well. The red tide mostly occurred in July, August, September and October. from multiple linear regression, the meteorological factors governing the mechanisms of the increase in the number of red tide occurrences are found to be a water temperature, rainfall, sunshine duration and wind velocity. But water temperature as the limited factor controlling the growth of phytoplankton (Cochlodinium polykrikoids) in 15∼$30^{\circ}c$. NO = 8.089 - 0.319WT + 0.019RF + 0.141SD + 0.l19WV (R = 0.897) in August NO = 7.531 - 0.327WT + 0.027RF + 0.208SD + 0.208WV (R = 0.894) in September Here, NO is the number of occurrence for red tide, WT is water temperature, RF is rainfall, SD is sunshine duration and WV is wind velocity, respectively. The necessary times till the day of red tide occurrence verse the day when water temperature reaches $15^{\circ}c$ are 78∼104 days, then it should be divided the coastal waters into 4 areas by the comparison among the accumulated sunshine duration, water temperature and rainfall as follows; the South West Coast (SW), South Middle Coast (SM), South East Coast(SE) and East South Coast (ES). The coastal areas that red tide occurs were complicated and various by change of marine environments. Usually red tide with a high concentrations (individual number, cells/ml) appeared in SM and SE. It was found that the general situations for the frequencies of red tide formation are mainly concentrated to 24.5∼$25^{\circ}c$ (high water temperature) and eve. 1000 cells/ml (high individual number) such as the category of red tide warning.

Design of a 48MHz~1675MHz Frequency Synthesizer for DTV Tuners (DTV 튜너를 위한 48MHz~1675MHz 주파수합성기 설계)

  • Ko, Seung-O;Seo, Hee-Teak;Kwon, Duck-Ki;Yu, Chong-Gun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.5
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    • pp.1125-1134
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    • 2011
  • In this paper a wideband frequency synthesizer is designed for DTV tuners using a $0.18{\mu}m$ CMOS process. It satisfies the DTV frequency band(48~1675MHz). A scheme is proposed to cover the full band using only one VCO and reliable broadband characteristics are achieved by reducing the variations of VCO gains and frequency steps. The simulation results show that the designed VCO has frequency range of 1.85~4.22GHz, phase noise at 4.22GHz of -89.7dBc/Hz@100kHz, gains of 62.4~95.8MHz/V(${\pm}21.0%$) and frequency steps of 22.9~47.9MHz(${\pm}35.3%$). The designed VCO has a phase noise of -89.75dBc/Hz at 100kHz offset. The designed synthesizer has a lock time less than $0.15{\mu}s$. The measured VCO tuning range is 2.05~3.4GHz. The frequency range is shifted down but still satisfy the target range owing to the design for enough margin. The designed circuit consumes 23~27mA from a 1.8V supply, and the chip size including PADs is $2.0mm{\times}1.5mm$.

A Study on Decision Factors for Residency in the Hinterland of Incheon New Port in Companies' Perspective (기업 관점의 인천신항 배후단지 입주결정 요인에 관한 연구)

  • Yoon, Jung-Ho;Jeon, Jun-Woo;Yeo, Gi-Tae
    • Journal of Navigation and Port Research
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    • v.40 no.3
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    • pp.121-128
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    • 2016
  • The present study aimed to derive decision factors for residency in the hinterland of Incheon New Port that is undergoing the development of port hinterlands and changes in leasing methods considered from the perspective of companies and analyze the priorities of determinants for residency through Fuzzy-AHP in order to present a direction to activate companies entries into the hinterland of Incheon New Port. When the comprehensive rankings of determinants for residency in the hinterland of Incheon New Port, rent levels among cost factors took the highest ranking with a value of 10.2% followed by the throughput of the port among market factors with a value of 8.2%, the scale of the market on the background with a value of 7.3%,, reduction in inland transport costs among cost factors with a value of 7.1%, connectivity to inland transportation networks among locational factors with a value of 6.7%, and designation as a free trade zone and the scale with a value of 6.4%. When seen from the viewpoint of companies to determine whether to move into the hinterland of Incheon New Port, the rent level should be provided to be more attractive compared to the hinterlands of ports in other regions. In addition, inland transportation costs which are a matter of the most serious concern of shippers in the capital region should be reduced and sea routes that can directly connect Incheon New Port to US ports and European ports should be opened.

A Study on the development of Ocean Education Model Course using Ocean Literacy -Focus on Busan Metropolitan City- (해양리터러시 개념에 기반한 해양교육 모델코스 개발에 관한 연구 -부산지역을 중심으로-)

  • Jeong, Woo-Lee;Moon, Serng-Bae
    • Journal of Navigation and Port Research
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    • v.38 no.5
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    • pp.437-442
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    • 2014
  • Ocean Literacy is an understanding of the ocean's influence on you and your influence on the ocean. This research developed the 7 ocean education model courses using ocean literacy based on the analysis of ocean education programs which executed 23 agencies in Busan. These model courses are combined in the type of indoor theory, indoor experience, field study and field experience. Also, this makes the guide map for ocean education in a 76cm*56cm size to distinguish and choose the course easily. This map is the format combined in geological location and tourist attraction spots in Busan, includes education centers, contents, lead time and so on, and it is possible for educatees to handle their preference and seasonality elastically. This map including ocean education model course is a milestone to activate ocean education, and is helpful to reach the goal of ocean education and to lead ocean professionals. In addition, this research presents the development of teaching materials, training aids to complement the weakness of indoor education, the development of cyber education through making video contents as the activation measures of ocean education.

Design and Development of Multiple Input Device and Multiscale Interaction for GOCI Observation Satellite Imagery on the Tiled Display (타일드 디스플레이에서의 천리안 해양관측 위성영상을 위한 다중 입력 장치 및 멀티 스케일 인터랙션 설계 및 구현)

  • Park, Chan-Sol;Lee, Kwan-Ju;Kim, Nak-Hoon;Lee, Sang-Ho;Seo, Ki-Young;Park, Kyoung Shin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.541-550
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    • 2014
  • This paper describes a multi-scale user interaction based tiled display visualization system using multiple input devices for monitoring and analyzing Geostationary Ocean Color Imager (GOCI) observation satellite imagery. This system provides multi-touch screen, Kinect motion sensing, and moblie interface for multiple users to control the satellite imagery either in front of the tiled display screen or far away from a distance to view marine environmental or climate changes around Korean peninsular more effectively. Due to a large amount of memory required for loading high-resolution GOCI satellite images, we employed the multi-level image load technique where the image was divided into small tiled images in order to reduce the load on the system and to be operated smoothly by user manipulation. This system performs the abstraction of common input information from multi-user Kinect motion and gestures, multi-touch points and mobile interaction information to enable a variety of user interactions for any tiled display application. In addition, the unit of time corresponding to the selected date of the satellite images are sequentially displayed on the screen and multiple users can zoom-in/out, move the imagery and select buttons to trigger functions.

Electrical Characteristics of RRAM with HfO2 Annealing Temperatures and Thickness (HfO2 열처리 온도 및 두께에 따른 RRAM의 전기적 특성)

  • Choi, Jin-Hyung;Yu, Chong Gun;Park, Jong-Tae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.663-669
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    • 2014
  • The electrical characteristics of RRAM with different annealing temperature and thickness have been measured and discussed. The devices with Pt/Ti top electrode of 150nm, Pt bottom electrode of 150nm, $HfO_2$ oxide thickness of 45nm and 70nm have been fabricated. The fabricated device were classified by 3 different kinds according to the annealing temperature, such as non-annealed, annealed at $500^{\circ}C$ and annealed at $850^{\circ}C$. The set and reset voltages and the variation of resistance with temperatures have been measured as electrical properties. From the measurement, it was found that the set voltages were decreased and the reset voltage were increased slightly, and thus the sensing window was decreased with increasing of measurement temperatures. It was remarkable that the device annealed at $850^{\circ}C$ showed the best performances. Although the device with thickness of 45nm showed better performances in the point of the sensing window, the resistance of 45nm devices was large relatively in the low resistive state. It can be expected to enhance the device performances with ultra thin RRAM if the defect generation could be reduced at the $HfO_2$ deposition process.

An Operating Scheme for the Course-based Qualification System at the Four-Year University Level: Focused on the KOREATECH Case (4년제 대학 과정평가형 자격과정 운영방안: 코리아텍 사례를 중심으로)

  • Oh, Chang-Heon;Kang, Seung-Chan;Min, Dong-Kyun;Om, Kiyong
    • Journal of Practical Engineering Education
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    • v.8 no.1
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    • pp.39-47
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    • 2016
  • Owing to increasing concern that jobseekers are wasting too much time and effort building up so-called "spec" skills to get a decent job, many companies including state-run enterprises are now hiring rookies based on their job competency rather than test scores unrelated to the job. However, universities which are mainly responsible for training professional personnel needed for various kinds of companies and factories are reluctant to adopt NCS-based educational courses. The NCS defines how much knowledge and skill are required to work in a certain industry and then evaluates them. Although the Korean government and several junior colleges have been tentatively operating the course-based qualification system at the "industrial technician" level since 2014, the results are falling far short of diverse stakeholders' expectations. Therefore, there are urgent needs to study how to develop NCS-based curriculum at the university level, and how to strengthen the linkage between work, training, and qualification.