• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.3
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• pp.8-17
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• 1999

무선 ATM망에서 다수 연결채널로부터 발생되는 트래픽의 서비스 질을 보장하고 한정된 무선 자원을 효율적으로 사용하기 위해서는 다중접속제어 기술이 중요한 설계요소 중 하나이다. 본고에서는 ATM 프로토콜 특성을 무선 구간에 까지 확장한 동적다중슬롯할당(DMSA: Dynamic Multi-Slot Assignment)기법의 단점 중 하나인 연결채널별 지연 성능의 차이에 대해 분석하고, 이를 해결하기 위하여 이동국으로부터 각 연결채널에 대해 전달되는 정보를 이용하여 중앙제어국에 가상큐를 도입하는 방안을 제안한다. 중앙제어국에서는 구성된 가상큐룰 이용하여 상향링크의 다음 한 프레임내 모든 타임슬롯에 대한 연결채녈 할당을 수행한다. 다양한 트래픽 소스에 대한 시뮬레이션을 통해 가상큐-동적다중슬롯할당 알고리즘이 기존의 동적다중슬롯할당 알고리즘에 비해 중앙제어국에서의 단순한 제어 부하만으로도 다수의 연결채널에 대해 균등한 설비스 질을 보장하고 지연 변이 특성의 성능 향상을 나타냄을 입증한다. 이러한 연구결과는 동종 혹은 이종의 트래픽을 가진 각 연결 채널에 대해 무선 구간의 분산 환경으로 인해 발생할 수 있는 불평등성을 해결함으로써 무선 ATM의 개념을 우선 ATM과 유사한 환경으로 분석할 수 있는 계기를 마련한 것으로 판단된다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.5
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• pp.1447-1454
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• 1991

본 로봇은 wheeled type과 legged type의 장점을 함께 가지고 있으므로 주행 속도가 빠르며 환경적응력이 좋다. 기존 로봇과 비교할때 Y.Icihkawa등이 개발한 HLV와 가장 유사하지만 모터 3개로 6개의 바퀴-다리 유닛을 구동하므로 모터15개로 5개의 바퀴-다리유닛을 구동하는 Ichikawa HLV와 동력전달구조에서 많이 상이하다. 뿐만아니라 본 로봇은 3개의 모터만 사용했기 때문에 주행제어가 훨씬 간단하고 제작 비가 저렴하며 장애물 및 계단승강시 걸음새가 훨씬 간단하다.(Ichikawa HLV 경우 뒷 쪽 2개의 다리를 동시에 들 수 없기 때문에 계단 승강시 몸체 회전을 적절하게 섞어야 한다.)

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.13 no.3
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• pp.141-147
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• 1984

2차원 채널 입구에서의 꿰떼 난류 유동하는 찬 물 위를, 같은 방향으로 빠르게 난류 유동하는 수증기의 응축은 액체필름 초기상태의 과냉 정도에 의하여서 응축능력이 정하여진다. 수증기와 액체의 채널 입구에서의 균일한 속도 및 온도, 그리고 채널 입구에서 액체와 증기가 차지하는 체적비, 즉 액체필름과 채널 높이를 알고 있을 때, 하류로 유동하면서 응축이 일어나는 현상을 예측하는 모델을 제안하고, 실험치와 비교한 것이다. 채널 입구에서 윗쪽으로는 더운 기체, 아래쪽으로는 찬 액체가 평행한 방향으로 유동하면서 접촉하고 평균적인 액체필름의 두께와 단열된 채널 벽체를 가정하여서, 기본방정식으로 연속방정식, 운동방정식을 세우고. 에너지와 운동량 전달 메카니즘 사이에 유사성이 존재한다고 가정하였으며, 전단응력의 크기는 필자의 모델을 적용하였다. 기본방정식을 기체 속도, 액체 속도, 필름의 두께, 압력에 대해서 수치해를 구하여서 동일조건 하에서 실험한 데이터와 비교하였다. 수증기와 액체 경계면에서의 전단응력은 매우 좋은 일치를 보여주고 있다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.57-57
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• 2019

실내 수준에서 조사되는 광량조건에 따른 자생 상록활엽 2종의 생육과 광화학반응을 조사하였다. 식물재료는 3년생 사철나무(Euonymus japonicus Thunb.) 및 2년생 돈나무[Pittosporum tobira (Thunb.) W. T. Aiton] 실생묘로 유리온실에서 재배하면서 실험에 사용하였다. 실내 광량은 10, 50, 100 및 200 PPFD(${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$)로 달리하여 8주간 재배하였으며, 광주기(12/12 h), 온도($25{\pm}1^{\circ}C$), 습도($55{\pm}3%$) 및 관수(1회/3일)조건은 고정되었다. 생육특성 및 광화학반응의 요인들이 측정되었으며, 동일기간 동안 유리온실에서 재배된 식물을 대조구로 사용하였다. 실험의 결과, 사철나무는 100, 200 PPFD의 광량에서 대조구에 비해 초장, 줄기직경, 엽수 및 엽장의 생육반응이 우수하였으며, 엽록소함량은 100 PPFD 이상의 광량에서 감소하였다. 또한 100 PPFD 이상의 광량에서 스트레스지수(Fm/Fo), 최대양자수율(Fv/Fm) 및 전자전달효율(ETo/RC)이 감소하였으며, 이는 대조구와도 유사한 경향이었다. 돈나무는 모든 광량조건에서 줄기직경과 엽폭을 제외하고 대조구와 관계없이 생육반응이 일정하였다. 그러나 스트레스지수와 최대양자수율은 10 PPFD 처리구에서 가장 낮게 조사되었고, 비광학적 에너지의 손실(DIo/RC)은 2.53으로 가장 높았다.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.2
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• pp.64-78
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• 2024

Storytelling is a communication technique to express and convey the story using various media, where the audience accepts the story, reinterprets the topic and interacts with the storyteller. It was assumed that the user's significance and awareness about the storytelling technique applied to historical theme parks would have an impact on the satisfaction of using the theme park and intention to revisit. In this study, it was purposed to derive the structural factors of spatial storytelling in historical theme parks, and to understand the impact of user's awareness and constituent factors on user responses. Based on previous researches, the structural factors of spatial storytelling in historical theme parks were derived related to theme, experientiality, unusualness, educationalness, unity, expressiveness, interactivity, and interest, and for which the users' awareness was surveyed. The survey was conducted targeting the users of Samguk Yusa Theme Park located in Gunwi-gun, Gyeongsangbuk-do, where the collected data was analyzed using EXCEL2020 and SPSS 21.0 statistical programs, and the results are as follows: First, the spatial storytelling technique applied as a conveying method of the theme of Samguk Yusa Theme Park affects users' satisfaction and intention to revisit, and most respondents responded that the storytelling was significant. Second, it showed that the significance of unusualness and educationalness among the awareness of significance of the spatial storytelling constituent factors of Samguk Yusa Theme Park has a significant impact on user's satisfaction, and the significance of unusualness, interactivity, educationalness, and interest has a significant impact on intention to revisit. Third, it showed that the awareness of interest, theme, and unity has a significant impact on user's satisfaction depending on the user's awareness of spatial storytelling constituent factors of Samguk Yusa Theme Park, and the awareness of interactivity and experientiality has a significant impact on intention to revisit. This study is meaningful in quantitative analysis and interpretation of the influence of storytelling on user's response to historical theme parks by the exploratory analysis of characteristic factors and spatial storytelling constituent factors on historical theme parks and deriving the structural factors of spatial storytelling in historical theme parks.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.75-86
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• 1994

To assess the role of adrenal medulla and renin-angiotensin system in the regulation of sympathetic neurotransmission, the pressor response to PNS was evaluated in pithed SHR and normotensive WKY or SDR with or without adrenal demedullation and/or enalapril pretreatment. Three weeks after adrenal demedullation, MAP and the heart rate of demedullated rats were similar to their corresponding sham-operated groups. The pressor response to PNS was frequency-dependent, and blocked by prazosin. In contrast to the normotensive rats, in SHR, the pressor response to PNS was attenuated in demedullated rats as compared with sham-operated rats. However, the attenuation of PNS-induced pressor responses in demedullated SHR was not observed in enalapril-treated SHR. The adrenal demedullation in SHR did not affect the plasma and aortic catecholamine contents in spite of the decreased catecholamine contents of adrenal gland, nor ACE activity in aortic strips. But, in WKY rats, the aortic catecholamines, especially epinephrine, contents as well as ACE activity were increased by adrenal demedullation. These results suggest that the facilitatory role of adrenal medulla in sympathetic neurotransmission depends upon the activation of renin-angiotensin system, and that the compensatory regulation of renin-angiotensin system takes place in normotensive rats but not in SHR.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.4
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• pp.679-694
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• 2013

According to the national information security white paper 2013, the number of hacking attempt in 2012 is 17,570 which is increased by 67.4% than in 2011, and it has been increasing year after year. The cause of this increase is considered as pursuit of monetary profit and diversification techniques of infection. However, because the development of malicious code faster than the increase in the number of experts to analyze and respond the malware, it is difficult to respond to security threats due to malicious code. So, the interest on automatic analysis tools is increasing. In this paper, we proposed the method of malware classification by similarity using malware DNA. It helps the experts to reduce the analysis time, to increase the correctness. The proposed method generates 'Malware DNA' from extracted features, and then calculates similarity to classify the malwares.

• Korean Journal of Cognitive Science
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• v.19 no.2
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• pp.163-175
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• 2008

Twelve Japanese students living in South Korea have been examined for their perceptual identification of an initial consonant in Korean syllables with or without a white noise. A confusion matrix was then subject to analyses of additive clustering, individual difference scaling, and probability of information transmission, the results of which were also compared to those of South Koreans. The Japanese in the present experiment confused /다/and/타/ most frequently, followed by /가/ and /카/, /자, 차, 짜/, /타/ and /따/, and so on. The results of additive clustering analysis of the Japanese significantly differed from those of the South Koreans. Individual difference scaling revealed dimensions of sonorant, aspiration and coronal. While South Koreans showed binary values on aspiration and tenseness dimensions, the Japanese did continuous values on such dimensions. An information transmission probability analysis revealed that the Japanese participants could not perceive very well such larynx features as tenseness and aspiration compared to the South Korean participants. The former group, however, perceived very well place of articulation features such as labial and coronal. The present results suggest that an approach dealing with structures of base representations is important in understanding the phonological categories of languages.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.783-790
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• 2007

G protein coupled receptors (GPCRs) transmit various extracellular signals into the cells. Upon binding of the ligands, conformational changes in the extracellular and/or transmembrane (TM) domains of CPCRs were propagated into the cytoplasmic (CP) domain of the molecule leading to the activation of their cognate heterotrimeric C proteins and kinases. Constitutively active GPCR mutants causing the activation of C Protein signaling even in the absence of ligand binding are of interest for the study of activation mechanism of GPCRs. Two classes of constitutively active mutations, categorized by their effects on the salt bridge between Ell3 and K296, were found in the TM domain of rhodopsin. Opsin mutants containing combinations of the mutations were constructed to study the conformational changes required for the activation of rhodopsin. Rhodopsin chromophore regenerated with 11-cis-retinal showed a thermal stability inversely correlated with its constitutive activity. In contrast, rhodopsin mutants exhibited a binding affinity to an agonist, all-trans-retinal, in a constitutive activity-dependent manner. In order to test whether the conformational changes responsible for the activation of trans-ducin (Gt) are the same as the conformation required for the recognition of rhodopsin kinase, analysis of the mutants were carried out with phosphorylation by rhodopsin kinase. Rhodopsin mutants containing combinations of different classes of the mutations showed a strong synergistic effect on the phosphorylation of the mutants in the dark as similar to that of Gt activation. The results suggest that at least two or three kinds of segmental and independent conformational changes are required for the activation of rhodopsin and the conformational changes responsible for activating rhodopsin kinase and Gt are similar to each other.

• The Journal of the Acoustical Society of Korea
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• v.32 no.6
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• pp.472-483
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• 2013

Actual maritime exercise for improving the capability of submarine sonar operator leads to a lot of cost and constraints. Sonar simulator maximizes the capability of sonar operator and training effect by solving these problems and simulating a realistic battlefield environment. In this study, a passive sonar simulator algorithm is suggested, where the simulator is divided into three modules: maneuvering module, noise source module, and sound propagation module. Maneuvering module is implemented in three-dimensional coordinate system and time interval is set as the rate of vessel changing course. Noise source module consists of target noise, ocean ambient noise, and self noise. Target noise is divided into modulated/unmodulated and narrowband/broadband signals as their frequency characteristics, and they are applied to ship radiated noise level depending on the vessel tonnage and velocity. Ocean ambient noise is simulated depending on the wind noise considering the waveguide effect and other ambient noise. Self noise is also simulated for flow noise and insertion loss of sonar-dome. The sound propagation module is based on ray propagation, where summation of amplitude, phase, and time delay for each eigen-ray is multiplied by target noise in the frequency domain. Finally, simulated results based on various scenarios are in good agreement with generated noise in the real ocean.