• Journal of Advanced Marine Engineering and Technology
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• 제28권3호
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• pp.466-474
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• 2004

The characteristics of liquefied butane spray are expected to be different from conventional diesel fuel spray, because a flash boiling spray is expected when the surround pressure is below the saturated vapor pressure of the butane(0.23MPa 98K). The axial velocities. radial velocities. and size distributions in butane sprays were measured with PDPA(Phase Doppler Particle Analyzer) system. Sprays were macroscopically observed by using the high speed camera in case that the surround pressure is 0.37MPa and 0.15MPa. respectively. Compared with the conventional spray. the reversed results were investigated when the surround pressure is below the saturated vapor pressure of the butane.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2403-2406
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• 2003

When viewing images, the relative luminance of the surround has a profound impact on the apparent contrast of the image. The dark surround causes the image elements to appear lighter than those viewed in an illuminated surround. For this reason, it is worthwhile to briefly review the general results of brightness sealing under a various viewing condition. Two of the most often cited parers on the topic of brightness scaling are Stevens-stevens and Bartleson-Breneman's function. There are, however, significant differences between the perceptual functions for simple-field and complex-field viewing. In this paper, we research the relationship between Steven's power law and Bartleson-Breneman's function. We present an appropriate brightness perception function due to TV system viewing conditions. Highlight luminance peak and absolute brightness threshold value in various adaptation levels are obtained from the proposed brightness function . Also, the luminance value of black level to produce the same contrast ratio with variety of display highlight luminance peak is obtained from the proposed brightness function.

• The Journal of the Acoustical Society of Korea
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• 제28권1E호
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• pp.29-34
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• 2009

MPEG4 High Efficiency Advanced Audio Coding (HE-AAC) and MPEG Surround are one of the most efficient combinations for low bit rate multi-channel audio coding. Based on the fact that these two codecs have identical quadrature mirror filter (QMF) analysis and synthesis structures, we propose a dual-domain connection scheme for the codecs. Specifically two time-domain connection methods are analyzed and compared to the QMF subband-domain connection method. Experimental results show that both the time-domain connection methods cause no subjective sound quality degradation compared to the QMF subband-domain connection method, which verifies that one can select either of them depending on application scenarios.

• 인포메이션 디스플레이
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• 제15권5호
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• pp.22-32
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• 2014

The current research intends to quantify the surround luminance effects on the shape of spatial luminance CSF and to propose an image quality evaluation method that is adaptive to both surround luminance and spatial frequency of a given stimulus. The proposed image quality method extends to a model called SQRI[8]. The non-linear behaviour of the HVS was taken into account by using CSF. This model can be defined as the square root integration of multiplication between display MTF and CSF. It is assumed that image quality can be determined by considering the MTF of the imaging system and the CSF of human observers. The CSF term in the original SQRI model was replaced by the surround adaptive CSF quantified in this study and it is divided by the Fourier transform of a given stimulus. A few limitations of the current work should be addressed and revised in the future study. First, more accurate model predictions can be achievable when the actual display MTF is measured and used instead of the approximation. Then, a further improvement to the model prediction accuracy can be made when chromatic adaptation of the HVS is taken into account[45-46].

• 반도체디스플레이기술학회지
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• 제22권3호
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• pp.125-129
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• 2023

In this paper, we propose a method to design and implement a smart pipeline information management system that can provide visualization information linked to GIS and roadmap based on the construction of precise pipeline buried information. The smart pipeline information management system consists of a positioning device for high-precision pipeline location measurement and surround view image data recording, a database for data storage and management, and a mobile app for remote monitoring and management. It connects surrounding image data and location data with GIS and roadmap. Convenience and accessibility of management can be improved.

• 방송과미디어
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• 제2권4호
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• pp.29-37
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• 1997

• 한국전문물리치료학회지
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• 제12권4호
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• pp.12-19
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• 2005

The purpose of this study was to investigate the possibility of virtual moving surround (VMS) on static balance in the patients with balance dysfunction. Eighty three subjects who were admitted or treated as an outpatient, or a family member, at the department of rehabilitation unit of university hospital were recruited to participate. Subjects were three groups based on their overall medical status: healthy, diabetic neuropathy and stroke. Each group was tested for static balance with a forceplate during static standing with VMS. The virtual movement was simulated with a head mounted display. The parameters for static balance were total sway path. In this study, the parameters of postural control for patients with diabetic neuropathy and stroke subjects were significantly increased in conditions elicited with the VMS. In the healthy elderly participants, the total sway path was not significantly different under virtual movement conditions. Therefore, VMS could be used in the evaluation and treatment of the patients with balance dysfunction.

• 전자공학회논문지
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• 제51권7호
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• pp.89-95
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• 2014

주위 밝기 및 환경에 따라서 LED 조명등의 밝기를 조절하기 위한 장치를 PWM 기술과 전력 소자를 이용하여 구현하였다. 주위의 광량 측정을 위하여 CdS 센서를 사용하였으며, PWM 신호 생성을 위하여 MCU를 사용하여 제어 보드를 설계한 다음 광량에 따라 듀티비를 조절하였다. 고전압, 대전류를 필요로 하는 LED 조명등을 디밍하기 위하여 전력 소자를 사용하여 DC 전원장치의 출력을 스위칭하였으며, PowerMOSFET, IGBT, PowerBJT를 각각 사용하여 특성을 서로 비교하였다. 실험결과 선형성 면에서는 IGBT가 양호하였으나, 효율 및 가격 면까지 고려하면 PowerBJT도 우수한 특성을 보였다.

• 대한전자공학회논문지SP
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• 제42권5호
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• pp.19-28
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• 2005

TV와 PC 모니터와 같은 컬러 디스플레이 장치 사용하는 실제 시환경은 표준 시환경과 상당히 다르다. 주위 시환경의 휘도와 색도의 변화에 따라 인간 시각계는 색 순응이 일어나게 되고, 사용자는 디스플레이 상에 재현된 측색적으로 동일한 색을 서로 다르게 느끼게 된다. 따라서 디스플레이에 재현된 색이 표준 시환경 하에서의 원래 색과 동일하게 재현하는 것이 중요하다. 본 논문에서는 동일한 휘도 조건에서 주위 조명광의 색도 변화에 따른 색 순응 모델을 제안한다. 제안한 색 순응 모델은 주위 시환경의 휘도 조건과 색도에 따라 시 세포의 L, M, 및 S 에 대한 감도의 이득을 모두 비선형 함수로 구한다. 그리고 제안한 색 순응 모델의 최적 이득 계수 값은 Breneman 색 순응 실험의 대응색 데이터들로부터 구한다. 제안한 색 순응 모델과 기존 모델들의 성능을 평가해 본 결과, 제안 방식의 색 순응 모델이 기존의 모델에 비해서 전 휘도 조건에서 매우 우수한 성능을 가짐을 확인하였다. 또한, 실제 시환경하에서 제안한 색 순응 모델을 이용하여 재현한 대응색이 표준 시환경 하에서의 원래의 색과 동일하게 보이는 것을 확인하였다.

• 대한약리학회:학술대회논문집
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• 대한약리학회 2006년도 The 6th Congress of the Federation of Asian and Oceanian Physiological Societies
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• pp.102.2-102.2
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• 2006