• 디지털콘텐츠학회 논문지
• /
• 제6권2호
• /
• pp.131-135
• /
• 2005

차세대 단말은 정보통신 기술의 융합(convergence)에 따라 이동전화, 무선랜, 휴대인터넷, DMB, 멀티미디어, 모바일 게임, 센서(스마트태그, 생체인식) 등 휴대 단말의 기능들이 하나의 통일된 사용자 인터페이스 융합을 통하여 다양한 요구를 수용하게 될 것이다. 또한 차세대 이동단말은 기본적으로 서로 다른 망에 접속이 가능한 다중모드를 지원하여야 하며, 서로 다른 망으로부터 다양한 서비스를 지원받을 수 있도록 높은 성능과 다양한 기능을 지원하여야 한다. 따라서 본 논문에서는 차세대 이동단말의 발전전략을 통해 차세대 단말의 최소 요구사항 및 요소기술에 대해 검토하고자 한다.

• 소프트웨어공학소사이어티 논문지
• /
• 제28권1호
• /
• pp.23-28
• /
• 2019

최근 이미지 처리 응용을 위한 심층 신경망 모델의 효과적 테스팅을 위해 해당 모델이 올바르게 예측하지 못하는 코너 케이스에 해당하는 행동을 보이는 데이터를 자동 생성하는 연구가 활발히 진행되고 있다. 본 논문은 문장 분류 심층 신경망 모델에 기반하고 있는 버그 담당자 자동 배정 시스템의 테스트를 위해 입력 데이터인 버그 리포트의 내용에서 임의의 단어를 선택해 동의어로 변형하는 테스트 데이터 생성기법을 제안한다. 그리고 제안하는 테스트 데이터 생성 기법을 사용한 경우와 기존의 차이 유발 테스트 데이터 생성 기법을 사용했을 경우를 다양한 뉴런 기반 커버리지를 중심으로 비교 평가한다.

• 대한조선학회논문집
• /
• 제32권1호
• /
• pp.58-69
• /
• 1995

본 논문에서는 이상유체모델에서의 비선형 자유표면파의 발생, 전파 및 상호간섭에 대한 비정상 문제의 수치해법을 개발하였다. 본 수치해법은 매 시간 스텝에서 비선형 축차해법을 이용한 음함수적(implicit)방법이다. 속도장함수를 구하기 위하여 경계접합좌표계를 도입한 유한차분법을 이용하였다. 본 수치해법의 유효성과 효율성의 검증을 위하여 타원형 유체의 변형과 바닥의 일부분이 올라옴으로서 발생하는 자유표면파의 생성에 대한 두 가지 계산결과를 보여준다.

• 대한조선학회논문집
• /
• 제47권3호
• /
• pp.359-368
• /
• 2010

This paper describes the generation and propagation of internal solitary wave in a two-layer fluid system by numerical analysis. Characteristics of interfacial soliton such as wave type, wave height, wave celerity are investigated numerically with respect to an extent of initial disturbance, fluid thicknesses of the two fluids and etc. The difference between the internal wave propagation on sloping beach and flat bottom was also examined. Laboratory experiments were conducted in the wave flume and compared with the results of numerical computation for verification.

• 설비공학논문집
• /
• 제24권11호
• /
• pp.792-798
• /
• 2012

A general concept on the definition of the second law efficiencies of thermodynamic cycles is introduced. The efficiency is defined to be proportional to the entropy generation divided by the maximum possible entropy generation. This way of definition of the cycle efficiency is clear and concise and, moreover, follows faithfully the concept of the second law of thermodynamics. This definition is applied to heat engine, refrigerator and heat pump. The second law efficiencies of heat engine and refrigeration cycles are derived, which are the same as the existing ones, respectively. The second law efficiency of heat pump, however, finds to be different from the existing one. Discussion is given about the difference and its cause.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회B
• /
• pp.1959-1963
• /
• 2007

SMES systems need cryogenic cooling systems. Conduction cooling system has more effective, compact structure than cryogen. In general, 2 stage GM cryocoolers are used for conduction cooling of HTS SMES system. 1st stages of cryocoolers are used for the cooling of current leads and radiation shields, and 2nd stages of cryocoolers for HTS coil. For the effective conduction cooling of the HTS SMES system, the temperature difference between the cryocooler and HTS coil should be minimized. In this paper, a cryogenic conduction cooling system for HTS SMES is analyzed to evaluate the performance of the cooling system. The analysis is carried out for the steady state with the heat generation of the HTS coil and effects of the thermal contact resistance. The results show the effects of the heat generation and thermal contact resistance on the temperature distribution.

• 한국생물물리학회:학술대회논문집
• /
• 한국생물물리학회 2003년도 정기총회 및 학술발표회
• /
• pp.79-79
• /
• 2003

SHG (Second harmonic generation) can be used to probe the surface of centrosymmetric particles suspended in bulk isotropic solution, because it is forbidden in centrosymmetric media under the dipole approximation. Using this technique, we can study the transport dynamics of small organic dye molecules across liposome bilayers. Because molecules adsorbed on the outer layer are in opposite direction with that on the inner layer by symmetry, the SH field is proportional to the difference between the number density of dye molecules on both sides of the bilayer, and the time dependence of the SH intensity is related to the time constant of the molecular transportation of dye molecules across liposome bilayers.

• 한국시스템다이내믹스연구
• /
• 제12권4호
• /
• pp.93-124
• /
• 2011

The introduction of competition in the generation of electricity has raised the fundamental question of whether markets provide the right incentives for the provision of the capacity needed to maintain system reliability. Capacity mechanisms are adopted around the world to guarantee appropriate level of investment in electricity generation capacity. In this study, we discuss these approaches and analyze the capacity pricing mechanisms from the adequacy perspective. We conclude that the design of capacity mechanism is very important to decrease electricity spot price and increase total electric capacity. Specifically, the constant of capacity pricing mechanism made a difference to the performance of electricity market. However, the slope of capacity price mechanism is better than the constant of that in improving performance of electricity market.

• Journal of Electrical Engineering and Technology
• /
• 제8권1호
• /
• pp.176-182
• /
• 2013

In this study, we examine the tracking happen in a polyvinyl-chloride-sheathed flat cord (PVCSFC), which is widely used as a distribution cord. The study classifies the bridge current via the formed conductive paths during tracking in the PVCSFC. Further, it attempts to distinguish the characteristics of heat generation and heat transfer by kind of bridge current. When the PVCSFC is in the static state, the bridge currents flow only through the electrolyte bridge. In the case of the carbonized PVCSFC, the bridge currents flow through one or more conductive paths. One is the electrolyte bridge, the other is the bridge that is consisted electrolyte and carbonized insulation. Currents flowing through different conductive paths have different heat generation and transfer characteristics. As the bridge current flowing in the conductive path consisting of electrolyte and carbonized insulation increases, the temperature difference between the surface of the PVCSFC and ambient air also increases correspondingly.

• 한국조명전기설비학회지:조명전기설비
• /
• 제13권2호
• /
• pp.203-203
• /
• 1999

In this paper, high concentration·yield multi-discharge type ozonizer( MDO ) of new discharge type using superposed silent discharge was designed and manufactured. MDO can be consisted with 3 kind of superposed silent discharge type ozonizer( SDO ) in accordance with power supply method that supplying power, which has 180[°] phase difference, to 3 electrodes and double gap. At the moment discharge characteristics and ozone generation characteristics of each SDO were investigated in accordance with quantify of supplied gas, the number of SDO, and the shapes of each SDO. In result ozone generation characteristics of 17185[ppm] and 783[g/kWh] were obtained, and whorl ozone of 17185[ppm] was in contact with dyeing water waste decolonization characteristics was excellent, so it confirmed that MDO could be used as water environment improvement facility.