• 설비공학논문집
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• 제8권1호
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• pp.166-175
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• 1996

In recent years, air-conditioning units designed with higher efficiency and more compactness are required due to emphasis on energy efficiency in home electrical appliances. This trend in the air-conditioning industries has accelerated the development of improved heat exchanger with a better performance in heat transfer aspects. In this study, experiments were performed to investigate the shape and configuration of fins affecting on the performance of the conventional fin-and-tube type heat exchanger equipped in a commercial air conditioners. The geometry similtude method was employed to measure the heat transfer coefficient and pressure drop. Experimental results show that this method is very useful to analyze the heat transfer characteristics of the fin-and-tube type heat exchanger. It is also found that the slit fin has better performance than the conventional fin type in the air conditioners. The present results indicate that heat transfer from the fin si influenced by the parameters such as the forming area of the slit fin, the type of interrupted surfaces like a louver or slit, slit patterns and slit raised direction, and it also affects the overall heat exchanger performance.

• 대한전자공학회논문지SD
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• 제41권6호
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• pp.1-7
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• 2004

본 논문에서는 2차원 양자 역학적 모델링 및 시뮬레이션(quantum mechanical modeling and simulation)으로써, 자기정렬 이중게이츠 구조(self-aligned double-gate structure)인 FinFET에 관하여 결합된 푸아송-슈뢰딩거 방정식(coupled Poisson and Schrodinger equations)를 셀프-컨시스턴트(self-consistent)한 방법으로 해석하는 수치적 모델을 제안한다. 시뮬레이션은 게이트 길이(Lg)를 10에서 80nm까지, 실리콘 핀 두께($T_{fin}$)를 10에서 40nm까지 변화시켜가며 시행되었다. 시뮬레이션의 검증을 위한 전류-전압 특성을 실험 결과값과 비교하였으며, 문턱 전압 이하 기울기(subthreshold swing), 문턱 전압 롤-오프(thresholdvoltage roll-off), 그리고 드레인 유기 장벽 감소(drain induced barrier lowering, DIBL)과 같은 파라미터를 추출함으로써 단채널 효과를 줄이기 위한 소자 최적화를 시행하였다. 또한, 고전적 방법과 양자 역학적 방법의 시뮬레이션 결과를 비교함으로써,양자 역학적 해석의 필요성을 확인하였다. 본 연구를 통해서, FinFET과 같은 구조가 단채널 효과를 줄이는데 이상적이며, 나노-스케일 소자 구조를 해석함에 있어 양자 역학적 시뮬레이션이 필수적임을 알 수 있었다.

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.304-307
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• 2012

A three specimen of Icelus toyamensis, belonging to Cottidae, Scorpaeniformes, was firstly collected from the East Sea, Korea during 2007-2009. We herein described the species as the first record from Korea on the basis of these specimens. Icelus toyamensis is characterized by the following morphological combinations: spinous scales absent on the base of dorsal fin; small ctenoid scales scattered on body sides; gill rakers are short, tubular, and relatively broad; the uppermost preopercular spine is sharp and simple; dorsal fin rays VIII-IX, 20-21; anal fin soft rays 18-19; pectoral fin rays 18, and vertebrae 40-41. New Korean name of I. toyamensis is proposed as "Min-jul-ga-si-hoet-dae."

• 한국전기전자재료학회논문지
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• 제23권6호
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• pp.449-453
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• 2010

In this paper, the electrical characteristics of Fin-type SONOS(silicon-oxide-nitride-oxide-silicon) flash memory device with different trapping layers are analyzed in depth. Two kinds of trapping layers i.e., silicon nitride($Si_3N_4$) and hafnium oxide($HfO_2$) are applied. Compared to the conventional Fin-type SONOS device using the $Si_3N_4$ trapping layer, the Fin-type SOHOS(silicon-oxide-high-k-oxide-silicon) device using the $HfO_2$ trapping layer shows superior program/erase speed. However, the data retention properties in SOHOS device are worse than the SONOS flash memory device. Degraded data retention in the SOHOS device may be attributed to the tunneling leakage current induced by interface trap states, which are supported by the subthreshold slope and low frequency noise characteristics.

• 한국전기전자재료학회논문지
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• 제33권2호
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• pp.88-92
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• 2020

Thermal effects in bulk and SOI FinFETs are briefly reviewed herein. Different techniques to measure these thermal effects are studied in detail. Self-heating effects show a strong dependency on geometrical parameters of the device, thereby affecting the reliability and performance of FinFETs. Mobility degradation leads to 7% higher current in bulk FinFETs than in SOI FinFETs. The lower thermal conductivity of SiO₂ and higher current densities due to a reduction in device dimensions are the potential reasons behind this degradation. A comparison of both bulk and SOI FinFETs shows that the thermal effects are more dominant in bulk FinFETs as they dissipate more heat because of their lower lattice temperature. However, these thermal effects can be minimized by integrating 2D materials along with high thermal conductive dielectrics into the FinFET device structure.

• 한국어류학회지
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• 제28권2호
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• pp.121-124
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• 2016

뱀장어목 붕장어과에 속하는 Ariosoma meeki 1개체 (전장 485.2 mm)가 2015년 6월 경상남도 창원시에서 처음으로 채집되었다. 본 종은 몸 전체에 비늘이 없고, 등지느러미와 뒷지느러미가 꼬리지느러미와 연결되어 있으며, 후비공이 피판으로 덮여 있고, 60개의 항문 전 측선공 및 15개의 가슴지느러미 연조를 가지며, 두부에 감각공이 없고, 눈 뒤쪽에 2개의 검은 점을 가진다. 한국에서 새롭게 보고되는 A. meeki의 국명으로 "눈테붕장어"를 제안한다.

• 한국수산과학회지
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• 제56권6호
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• pp.909-915
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• 2023

A specimen of longarm mullet Moolgarda cunnesius (Valenciennes, 1836) belonging to the family Mugilidae was collected from Yerae-dong, Seogwipo-si, Jeju-do Island, Korea, on July 19, 2023, using a hand net. The specimen was identified as Moolgarda cunnesius based on its morphological traits, including pectoral fin reaching the third or fourth spine of the first dorsal fin, anal fin higher than the first and second dorsal fin, two dorsal and caudal fin membranes with small melanophores, and a slightly convex interorbital region. Furthermore, molecular analysis, specifically comparison of the 623 base pairs of mitochondrial DNA COI sequences, confirmed that our specimen perfectly matched M. cunnesius. It is well known that the species is widely distributed in the Indo-West Pacific Ocean, including the Red Sea, Taiwan, and northern Australia, and this study shows that it also inhabits the Jeju-do Island, Korea. Additionally, we propose a new Korean name 'gin-pal-sung-eo' for this species.

• 대한전자공학회논문지SD
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• 제47권3호
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• pp.1-6
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• 2010

Saddle MOSFET의 모서리의 효과에 대한 고전역학과 양자역학적 시뮬레이션의 비교분석을 3차원 수치 시뮬레이터를 사용하여 수행하였다. 비교분석 결과 양자역학적 시뮬레이션에서는 실리콘 핀의 단면에서의 정확한 최대 전자 밀도의 위치와 크기를 제공함으로써 소자의 정확한 설명을 제공하는 것을 보여 주었고, 이를 이용하여 모서리 효과 및 그것이 소자의 문턱전압의 특성을 미치는 영향의 정확한 분석이 실행되었다. 또한, 모서리 효과를 억제하기 위해서 실리콘 핀의 모서리를 둥글게 하거나 구석의 바디도핑을 낮추는 두 가지 가능한 기법을 제시했다.

• Fisheries and Aquatic Sciences
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• 제17권3호
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• pp.381-384
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• 2014

A single specimen belonging to the family Diodontidae was collected from Seo-gwi-po, Jeju Island, Korea in July 2013 and was identified as Diodon hystrix Linnaeus, 1758, a species new to the Korean fish fauna. The species is characterized by 14 dorsal fin rays, 14 anal fin rays, spines on the dorsal and ventral surfaces of the caudal peduncle, and many small black spots on all fins except the anal fin. The most similar species, Diodon holocanthus, is well distinguished from D. hystrix by the absence of black spots on the dorsal and caudal fins, and the lack of a spine on the dorsal surface of the caudal peduncle. Accordingly, we describe herein the morphological traits of D. hystrix and suggest its new Korean name, "Jan-jeom-bak-i-ga-si-bok".

• 수산해양기술연구
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• 제57권2호
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• pp.127-133
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• 2021

A single specimen of Chaetodon vagabundus Linnaeus, 1758 belonging to the family Chaetodontidae was collected on September 8, 2013 in Yerae-dong, Seogwipo-si, Jeju Island, Korea. The morphological characteristics of C. vagabundus are similar to C. auriga and C. auripes in having dark vertical stripes cross the eye, but differs from C. auriga, which has high dorsal fin extended between spine and soft rays without concavity and has blotch of circle in dorsal fin, and from C. auripes which has yellow body, big of eye proportion and a black stripe along the caudal peduncle during the immature stage. C. vagabundus has eye-like black spots on dorsal fin and black vertical stripe extended from the anterior dorsal soft ray to the middle of the anal fin along the caudal peduncle. Molecular analysis results showed that our specimen perfectly matched C. vagabundus in the mitochondrial DNA COI sequences. Therefore, we use the Korean name, "Hwang-jul-na-bi-go-gi" for C. vagabundus proposed by Kim et al. (2020).