• 한국정보통신학회논문지
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• 제19권1호
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• pp.185-191
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• 2015

본 논문에서는 원자력 안전등급 제어기기의 안전 통신망 구현을 위한 원자력 안전등급 통신 보드를 제안한다. 원자로 보호계통이 아날로그에서 디지털화되면서 디지털 통신망을 사용하게 되었다. 디지털 통신망은 원자력 안전등급에 사용되는 통신망으로 안전등급에서 요구하는 성능 및 시험을 통과한 통신보드가 제공되어야 한다. 통신 프로토콜 계층은 OSI 7 계층 중 물리계층, 데이터링크 계층, 어플리케이션계층만을 사용한다. 데이터 링크 계층에서는 사이버 보안을 위해 데이터 패키지를 변경하였다. 데이터 건전성을 위해 CRC32를 사용 하였으며 데이터 수신에 대해서는 재요청 및 응답을 하지 않는 단방향 통신만을 함으로써 원자력 안전계통에 영향을 주지 않게 설계 되었다. 또한 원자력안전등급을 획득하기 위해서 요건, 설계, 검증의 절차에 따라 설계하였다. 하드웨어검증을 위해 전자파 시험, 노화분석 시험, 육안검사, 번인시험, 내환경 시험 및 내진 시험과 같은 기기 검증을 수행 하였다. 또한 FPGA 펌웨어 검증을 위해 IEEE 1074의 생명주기를 준수하여 단위시험과 통합 시험을 실행 하였다[1-3].

• 전자공학회논문지SC
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• 제38권5호
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• pp.33-41
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• 2001

본 논문에서는 마이크로프로세서를 이용한 디지털 전기인두기를 설계하여 기존의 아날로그 전기인두기와 비교 검토하였다. 설계된 디지털 전기인두기에서는 두 가지의 개선된 온도제어 특성을 보였다. 첫째로, 사용자가 설정한 온도와 인두팁의 실제 온도편차를 개선하였는데, 주위환경을 각각 $5[^{\circ}C]$와 $25[^{\circ}C]$에서 전기인두기의 설정온도를 $200[^{\circ}C]$, $300[^{\circ}C]$, $400[^{\circ}C]$, $480[^{\circ}C]$로 설정하였을 때, ${\pm}1.8[^{\circ}C]$를 벗어나지 않는 안정한 온도편차를 보였으며, 이를 실험으로 확인하였다. 두 번째, 사용자가 납땜할 때 인두팁에서 변하는 온도편차를 개선하였는데, 1[g]의 납으로 전기인두기의 설정온도를 $200[^{\circ}C]$, $300[^{\circ}C]$, $400[^{\circ}C]$, $480[^{\circ}C]$로 설정하였을 때, 아날로그 전기인두기는 $6[^{\circ}C]{\sim}10[^{\circ}C]$의 편차를 보인 반면, 설계된 디지털 전기인두기는 $2[^{\circ}C1{\sim}5[^{\circ}]$의 안정한 온도편차를 보였으며, 이를 실험으로 확인하였다.

• 한국해양환경ㆍ에너지학회지
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• 제8권1호
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• pp.46-52
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• 2005

대양을 운항하는 선박의 최적 항로계획 수립에 중요한 해양환경정보를 실시간으로 예보하는 시스템(MEIS)을 개발하였다. 예보정보는 위성관측 대양환경 자료를 기반으로 유럽중기기후예보센터가 처리한 실시간 자료를 바탕으로 하며, 장기 관측자료 데이터베이스에 근거한 통계적 정보와 함께 제공된다. MEIS시스템은 육상 기지국에 설치되어 해양환경정보를 취득하고 처리하는 육상자료처리시스템(MEIS-Center)과 선박에 탑재되어 가공된 해양환경정보를 화상으로 구현하고 최적항로 선정을 돕는 선박탑재화상구현시스템(MEIS-Ship)으로 구성되며, 운항중인 선박과 육상기지국간의 정보 송수신을 위한 위성통신 시스템을 활용한다. 해양환경 요소는 바람, 파랑, 기압, 폭풍을 포함하며, 바람은 풍향과 풍속 정보를 제공하고, 파랑은 너울과 풍파로 구분하여 파고, 파향, 파주기 정보를 제공할 수 있다. 실시간 정보는 0.5°해상도로 5시간 간격의 10일 예보치가 매일 제공되며, 통계적 정보는 1.5° 해상도의 15년 관측자료를 이용하여 월평균 및 재현주기별 최대값이 산정된다. MEIS-Ship은 항로 시뮬레이션 기능을 제공하며, 설정된 항로에 대해 예보 및 통계적 해양환경정보를 그림 또는 표의 형태로 제공한다. MEIS는 예정 항로상의 정확한 실시간 해양환경 예보를 제공하므로 선박운항자가 항로의 위험도와 운항경제성을 고려하여 최적 항로를 선정하는 것이 가능하다.

• 유통과학연구
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• 제13권9호
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• pp.13-18
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• 2015

Purpose - This study investigates the effects of thought suppression on depression and uneasiness among college students likely to be influenced by smart phone addiction. Research design, data, and methodology - A total of 151 valid questionnaires were collected. The following analyses were conducted using SPSS 19.0 and AMOS 19.0: frequency, descriptive statistics, correlation, simple regression, and multiple regression. Results - Smart phone addiction increased uneasiness, depression, impulsiveness, and aggression. Moreover, uneasiness, depression, impulsiveness and aggression from smart phone addiction, had a negative influence on psychological wellbeing resulting in potential delinquent behavior. In addition, the addiction treatment relied heavily on drugs; therefore, such psychological treatment should be strengthened to control intermittent addiction. Conclusions - The results indicate that various kinds of research are needed to investigate personality and environmental factors that influence smart phone addiction. Additionally, studies on lessening smart phone addiction and living healthy lifestyles are needed. Moreover, psychological rehabilitation and treatment should be developed to lessen the rebound effect after thought suppression, to verify the effects of clinical application, and to prevent intermittent addiction.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.95-97
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• 2005

Communication, Ocean, and Meteorological Satellite (COMS) to be launched in year 2008 will be the first Korean multi-purpose geostationary satellite aiming at three major missions, i.e.: communication, ocean, and meteorological applications. The development of systems for the meteorological mission sponsored by the Korea Meteorological Administration (KMA) consists of payloads, ground system, and data processing system. The program called COMS Meteorological Data Processing System (CMDPS) has been initiated for the development of data processing system. The primary objective ofCMDPS is to derive the level-2 environmental products from geo-Iocated and calibrated level 1.5 COMS data. Preliminary design for the level-2 data processing system consists of 16 baseline products and will be refined by end of 3rd project year. Also considered for the development are the necessary initial information such as land use and digital elevation map, algorithms for the vicarious calibration and procedures for the calibration monitoring, and radiative transfer model. Here, we briefly introduce the overall development strategy, flow chart for the intended baseline products, a few preliminary algorithm results and future plans.

• 자동차안전학회지
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• 제7권4호
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• pp.26-30
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• 2015

Exceeding the speed limit during vehicle driving is a key factor in the severity of lots of road accidents, and SLIF(Speed Limit Information Function) application is in the initial phase in Korea. SLIF helps the drivers to observe a speed limit when they are driving by providing alert and informing the current limit speed information based on external data using camera and/or digital map, for that reason, environmental conditions could be causes of SLIF malfunctions. In this study, design adequacy analysis of SLIF in respect of false recognition as the Korea traffic environment has been performed. As tentative results, road conditions and structure of speed limit sign as well as system performance often caused misrecognition.

• 한국군사과학기술학회지
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• 제15권1호
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• pp.66-74
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• 2012

The virtual target signal generator was developed to verify the shipborne tracking radar performance. It was used to DRFM(Digital RF Memory) method to generate the virtual moving targets. The target signal includes Doppler shift and RCS according to the target motion. And the signal generator can make jamming signal and clutter to test shipborne radar performance at real environmental condition. This paper described the functional diagram and the hardware configuration items to meet the test requirements for the tracking radar. And it showed the critical design points for the sub-systems. The signal generator which was developed in this paper shared the operational information of the radar with the radar command and control part. To test the frequency agility of the radar, it had the local oscillator which could do high speed frequency switching according to radar information. By communicating between the signal generator and the radar command and control part, the local oscillator of signal generator could be controlled every pulse. It reduced the instantaneous bandwidth of signal generator and minimized the spurious. So it lowered the probability of generating wrong targets.

• Journal of Communications and Networks
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• 제12권2호
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• pp.158-167
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• 2010

The energy efficiency of wireless infrastructure and terminals has been drawing renewed attention of late, due to their significant environmental cost. Emerging green communication paradigms such as cognitive radios, are also imposing the additional requirement of flexibility. This dual requirement of energy efficiency and flexibility poses new design challenges for implementing radio functional blocks. This paper focuses on the area vs. power trade-offs for the type of channel filters that are required in the digital frontend of a flexible, energy-efficient radio. In traditional CMOS circuits, increased area was traded for reduced dynamic power consumption. With leakage power emerging as the dominant mode of power consumption in nanoscale CMOS, these trade-offs must be revisited due to the strong correlation between area and leakage power. The current work discusses how the increased timing slacks obtained by increasing the parallelism can be exploited for overall power reduction even in nanoscale circuits. In this context the paper introduces the notion of 'area efficiency' and a metric for evaluating it. The proposed metric has also been used to compare the area efficiencies of different classes of time-shared filters.

• 한국산업보건학회지
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• 제18권1호
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• pp.1-10
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• 2008

In order to evaluate performance of anti-vibration gloves, it is necessary to measure the transmitted vibration to the hand and the applied forces at the same time while gripping the vibrating handle. In the study a system was developed to measure both the vibration and the forces. The system consists of a measurement handle with eight strain gauges and two accelerometers and a PC-based system with a software for signal processing, evaluation of the hand-transmitted vibration and for control of applied forces in the pre-determined range. The handle was installed on the vibration shaker which is strong enough so as not to be affected by dynamic coupling with the hand-arm. Whole procedure of ISO 10819:1996 to determine the vibration transmissibility of anti-vibration gloves was programmed into the system. As an example of the application, three subjects joined the test to get vibration transmissibilities of 9 anti-vibration gloves where each glove was tested twice a subject. Average and standard deviation of the corrected vibration transmissibility were also calculated. All tested gloves fulfilled criterion for M-spectrum($\overline{TR_M}$<1.0), but one glove fulfilled criterion for H-spectrum($\overline{TR_H}$<6.0),

• Smart Structures and Systems
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• 제5권4호
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• pp.381-395
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• 2009

The paper presents a case study in which the structural condition assessment of the East Bay bridge in Gibsonton, Florida is evaluated with the help of remote health monitoring techniques. The bridge is a four-span, continuous, deck-type reinforced concrete structure supported on prestressed pile bents, and is instrumented with smart Fiber Optic Sensors. The sensors used for remote health monitoring are the newly emerged Fabry-Perot (FP), and are both surface-mounted and embedded in the deck. The sensing system can be accessed remotely through fast Digital Subscriber Lines (DSL), which permits the evaluation of the bridge behavior under live traffic loads. The bridge was open to traffic since March 2005, and the collected structural data have been continuously analyzed since. The data revealed an increase in strain readings, which suggests a progression in damage. Recent visual observations also indicated the presence of longitudinal cracks along the bridge length. After the formation of these cracks, the sensors readings were analyzed and used to extrapolate the values of the maximum stresses at the crack location. The data obtained were also compared to initial design values of the bridge under factored gravity and live loads. The study showed that the proposed structural health monitoring technique proved to provide an efficient mean for condition assessment of bridge structures providing it is implemented and analyzed with care.