• 정보과학회 컴퓨팅의 실제 논문지
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• 제23권2호
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• pp.134-139
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• 2017

기존의 스크린 미러링 시스템들은 패킷 손실에 취약하며 제한적인 모바일 기기의 에너지를 효율적으로 사용하지 못하는 단점을 가지고 있다. 이를 극복하기 위해 본 연구에서는 패킷 손실에 강인하고 에너지 효율적인 스크린 미러링 시스템을 제안한다. 제안하는 시스템은 패킷 손실로 인한 스크린 미러링 영상의 품질 저하를 완화하기 위해 전방오류정정 기술의 한 종류인 랩터 코드를 적용한다. 그리고 모바일 기기의 효율적인 에너지 사용을 위해 스크린 미러링 데이터에 대한 트래픽 셰이핑을 적용하고, 랩터 인코딩 매개 변수를 조절한다. 제안하는 시스템은 싱글 보드 컴퓨터를 사용하여 실제로 구현 되었으며, WiFi Direct 네트워크 상에서 성능을 검증하였다.

• 한국분무공학회지
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• 제21권1호
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• pp.37-46
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• 2016

For the SI engines, at only full load, the pumping loss has a negligible effect, while at part load conditions, the pumping loss increases. To avoid the pumping loss, the spark-ignited engines are designed to inject gasoline directly into the combustion chamber. In the spark-ignited direct-injection engines, ignition probability is important for successful combustion and the flame propagation characteristics are also different from that of pre-mixed combustion. In this paper, a visualization experiment system is designed to study the ignition probability and combustion flame characteristics of spark-ignited direct-injection CNG fuel. The visualization system is composed of a combustion chamber, fuel supply system, air supply system, electronic control system and data acquisition system. It is found that ambient pressure, ambient temperature and ambient air flow velocity are important parameters which affect the ignition probability of CNG-air mixture and flame propagation characteristics and the injected CNG fuel can be ignited directly by a spark-plug under proper ambient conditions. For all cases of successful ignition, the flame propagation images were digitally recorded with an intensified CCD camera and the flame propagation characteristics were analyzed.

• 한국지진공학회논문집
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• 제20권6호
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• pp.391-400
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• 2016

For earthquake loss estimation of building structures in Gangnam-Gu district in Seoul, three scenario earthquakes were selected by comparison of the response spectra of these scenario earthquakes with the design spectrum in Korean Building Code (KBC 2009), and then direct losses of the building structures in the Gangnam-Gu district under each scenario earthquake are estimated. The following conclusions are drawn from the results of damage and loss in the second scenario earthquake, which has a magnitude = 6.5 and epicentral distance =15 km: (1) The ratio of building stocks undergoing the extensive and complete damage level is 40.0% of the total. (2) The amount of direct economic losses appears approximately 19 trillion won, which is 1.2% of the national GDP of Korea. (3) About 25% of high-rise (over 10-story) RC building wall structures, were inflicted with the damage exceeding moderate level, when compared to 60% of low-rise building structures. (4) From the economical view point, the main loss, approximately 50%, was caused by the damage in the high-rise RC wall building structures.

• 한국수소및신에너지학회논문집
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• 제5권2호
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• pp.111-119
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• 1994

Analysis of heat loss is needed to achieve the high performance and high efficiency in hydrogen engine. So, cooling losses at each part of the direct injection hydrogen fueled engine were measured to evaluate the behavior and distribution of heat loss. Unsteady instantaneous temperature and heat flux at cylinder head were measured by use of instantaneous temperature prove. And these results were compared with those of gasoline engine.

• 전자공학회논문지A
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• 제31A권12호
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• pp.16-22
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• 1994

In this paper, transmitter and receiver modules for free space optical interconnection are implemented and characterized. In the transmitter module, bias circuitry which inject current into the direct modulated laser diode is fabricated and in the receiver module, p-i-n diode is integrated with an MMIC amplifying stage. Laser diode has a direct-modulated bandwidth of 2 GHz at 1.4 Ith bias while p-i-n diode and amplifying stage has a bandwidth of 1.3 GHz and 1.5 GHz, repectively. Optical interconnection has a bandwidth of 1.3 GHz and linearly transmit modulated voltage signal up to 1.5 Vp-p. Measured loss of optical interconnection is 5dB which is composed of optoelectronic conversion loss of 15 dB, electrical impedance mismatch loss of 6.7 dB in transmitter module and gain of 18 dB in receiver module. Seperation between transmitter and receiver can be extended up to 50 cm by using a lens.

• Journal of Medicine and Life Science
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• 제20권1호
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• pp.43-47
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• 2023

Streptococcus suis (S. suis) is an emerging zoonotic pathogen that causes bacterial meningitis in humans. S. suis is an encapsulated gram-positive facultative anaerobic bacterium and is an important pathogen in pigs. This infectious disease usually manifests in humans as meningitis, endocarditis, septicemia, and arthritis. Most cases originate in Southeast Asia, and human S. suis infections are often reported in countries with a high density of pigs. Meningitis is a common clinical manifestation of S. suis infection. Moreover, hearing loss is a common complication that can be bilateral, profound, and/or permanent. This report presents two cases of bacterial meningitis and hearing loss caused by S. suis in patients without a history of direct exposure to pigs in an intensive pork industry region.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2002년도 정기총회 및 학술대회
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• pp.9-14
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• 2002

Direct-conversion receiver(DCR) architecture has superior advantages in size, cost, and power over superheterodyne receiver architectures. However, the use of direct-conversion receiver architecture has been limited due to the direct-current offset noise. The ac coupling, which is used to overcome the direct-current offset noise, causes an inter-symbol interference(ISI), whose effects can be effectively mitigated using an equalizer. In this paper, the performance of a direct-conversion receiver with ac coupling in the presence of direct-current offset is analyzed via computer simulation. The simulation result shows that by using decision feedback equalizer with LMS(Least Mean Square) algorithm, signal-to-noise ratio loss of the direct-conversion receiver compared to the idea receiver can be reduced to less than 1㏈ for corner frequencies as large as 10% of the symbol rate.

• 한국사회복지학
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• 제65권2호
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• pp.335-356
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• 2013

이 연구는 저소득층이 겪는 물리적 자원에서의 상실과 획득이 안녕감에 어떠한 영향을 주는지 그리고 이들이 경제환경과 상호작용하며 경험하는 경제적 안정감이 그러한 상실 및 획득의 영향을 받아 안녕감에 어떠한 역할을 하는지를 탐색하고자 하였다. 이에 자활센터를 이용하는 저소득층 남녀 성인 254명을 대상으로 물리적 자원의 상실과 획득, 경제안정, 안녕감의 수준을 살펴보고, 자원의 상실 및 획득 각각이 안녕감에 영향을 주는 관계와 이 관계에서 경제안정 수준이 보이는 매개역할을 구조방정식모형 분석으로 검토하였다. 주요 연구결과는 첫째, 참여자들은 물리적 자원을 약간 잃거나 얻은 수준이고 획득이 상대적으로 높았다. 둘째, 경제안정 및 안녕감과의 관계에서 자원상실은 유의한 부적관계를, 획득은 유의한 정적 관계를 보였다. 셋째, 자원상실은 경제안정과 안녕감 각각에 대해 유의한 부적인 직접효과를 보인 한편 경제안정의 감소를 통해 안녕감을 감소시키는 간접효과도 유의하였다. 끝으로, 자원획득 역시 경제안정과 안녕감 각각에 대해 유의한 직접효과를 보이고 또 경제안정을 통한 정적인 간접효과가 유의하여 자원상실과 획득 두 모형 모두에서 부분매개모형이 지지되었다. 이러한 결과에 기초하여 사회복지실천에서 저소득층 성인의 생활과 밀접히 관련되는 물리적 자원의 상실 및 획득, 경제안정, 안녕감을 활용할 방안과 조사연구에서 가질 수 있는 함의를 찾고 제언하였다.

• 한국지역사회생활과학회지
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• 제27권3호
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• pp.405-418
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• 2016

This study was conducted to explore the influences of loss experiences and depression on ego-integraty and transcendence of elderly Koreans and to identify gender differences in the relationships among loss experiences, depression, ego-integrity, and transcendence from 146 men and 194 women aged over 60 years in Busan, Gyeong-Nam, and Gyeong-Buk area. The main results were as follows: elderly men reported more loss experiences and transcendence than elderly women. Next, loss experiences influenced ego-integrity and depression mediated the relationship between loss experiences and ego-integrity. Also, ego-integrity had a direct effect on transcendence. Last, depression of elderly men fully mediated the relationship between loss experiences and transcendence. The relationship between loss experiences and ego-integration was partially mediated by depression for elderly women. These results were discussed in terms of gero-education and elderly welfare.

• 한국작물학회지
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• 제44권3호
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• pp.230-235
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• 1999

To study the effects of an urease inhibitor, N-(n-butyl)-thiophosphoric triamide (NBPT), and a nitrification inhibitor, dicyandiamide (DCD), on nitrogen losses and nitrogen use efficiency, urea fertilizer with or without inhibitors and slowrelease fertilizer (synthetic thermoplastic resins coated urea) were applied to direct-seeded flooded rice fields in 1998. In the urea and the urea+DCD treatments, NH$_4$$^{+}$ -N concentrations reached 50 mg N L$^{-1}$ after application. Urea+NBPT and urea+ NBPT+DCD treatments maintained NH$_4$$^{+}$ -N concentrations below 10 mg N L$^{-1}$ in the floodwater, while the slow-release fertilizer application maintained the lowest concentration of NH$_4$$^{+}$ -N in floodwater. The ammonia losses of urea+NBPT and urea+NBPT+DCD treatments were lower than those of urea and urea+DCD treatments during the 30 days after fertilizer application. It was found that N loss due to ammonia volatilization was minimized in the treatments of NBPT with urea and the slow-release fertilizer. The volatile loss of urea+DCD treatment was not significantly different from that of urea surface application. It was found that NBPT delayed urea hydrolysis and then decreased losses due to ammonia volatilization. DCD, a nitrification inhibitor, had no significant effect on ammonia loss under flooded conditions. The slow-release fertilizer application reduced ammonia volatilization loss most effectively. As N0$_3$$^{[-10]}$ -N concentrations in the soil water indicated that leaching losses of N were negligible, DCD was not effective in inhibiting nitrification in the flooded soil. The amount of N in plants was especially low in the slow-release fertilizer treatment during the early growth stage for 15 days after fertilization. The amount of N in the rice plants, however, was higher in the slow-release fertilizer treatment than in other treatments at harvest. Grain yields in the treatments of slow-release fertilizer, urea+NBPT+ DCD and urea+NBPT were significantly higher than those in the treatments of urea and urea+DCD. NBPT treatment with urea and the slow-release fertilizer application were effective in both reducing nitrogen losses and increasing grain yield by improving N use efficiency in direct-seeded flooded rice field.field.