• 공업화학
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• 제8권1호
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• pp.59-66
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• 1997

Di(10-hemisuccinyloxy)decyl muconate(DDM)와 di(6-hemisuccinyloxy)hexyl muconate(DHM)가 합성되었으며, 수용액에 분산되어 각각 $97^{\circ}C$과 $79^{\circ}C$에서 상전이를 나타내었다. 이들은 자체적으로, 또는 콜레스테롤이나 dioleoylphosphatidylethanolamine (DOPE)을 혼합하여도 리포좀을 형성하지 않았지만, phosphatidylcholine(PC)과 혼합되면 리포좀을 형성하였다. 리포좀막에서 DHM이 254nm의 자외선에 노출될 때 1,2-중합반응이 쉽게 진행되었다. DOPE/dioleoylphosphatidylcholine(DOPC)/DHM(3/3/1)으로 구성된 리포좀은 중성 pH에서는 안정하지만 약산성 pH에서는 불안정하여 pH 4.8과 5.8의 phosphate-buffered saline(PBS, $37^{\circ}C$)에서 30분과 50분 이내에 각각 봉입된 calcein의 방출이 완료되었다. calcein의 방출은 pH가 감소됨에 따라서 증가하며 pH 5.5와 5.0 근처에서는 각각 봉입 calcein의 50%와 100%가 방출되었다.

• Journal of Computational Design and Engineering
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• 제3권3호
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• pp.250-265
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• 2016

Owing to our rapidly aging society, accessibility evaluation to enhance the ease and safety of access to indoor and outdoor environments for the elderly and disabled is increasing in importance. Accessibility must be assessed not only from the general standard aspect but also in terms of physical and cognitive friendliness for users of different ages, genders, and abilities. Meanwhile, human behavior simulation has been progressing in the areas of crowd behavior analysis and emergency evacuation planning. However, in human behavior simulation, environment models represent only "as-planned" situations. In addition, a pedestrian model cannot generate the detailed articulated movements of various people of different ages and genders in the simulation. Therefore, the final goal of this research was to develop a virtual accessibility evaluation by combining realistic human behavior simulation using a digital human model (DHM) with "as-is" environment models. To achieve this goal, we developed an algorithm for generating human-like DHM walking motions, adapting its strides, turning angles, and footprints to laser-scanned 3D as-is environments including slopes and stairs. The DHM motion was generated based only on a motion-capture (MoCap) data for flat walking. Our implementation constructed as-is 3D environment models from laser-scanned point clouds of real environments and enabled a DHM to walk autonomously in various environment models. The difference in joint angles between the DHM and MoCap data was evaluated. Demonstrations of our environment modeling and walking simulation in indoor and outdoor environments including corridors, slopes, and stairs are illustrated in this study.

• 한국CDE학회논문집
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• 제17권2호
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• pp.79-90
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• 2012

In digital virtual manufacturing simulation, Digital Human widely used to optimal workplace design, enhancing worker safety in the workplace, and improving product quality. However, the case of ergonomics simulation solutions to support digital human modeling, Optimal DHM (Digital Human Model) data needed to develop and perform DHM will collect information related to the production process. So simulation developer has burden of collecting information. In this study, to overcome the limitations of existing solutions, we proposed the ADAGIO(Automated Digital humAn model development for General assembly usIng Ontology) framework. The ADAGIO framework was developed for DHM ontology to support optimal deployment of digital virtual environment and in order to ensure consistency of simulation components that are required for simulation modeling was made of a library.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.984-986
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• 1998

The volume holographic memory system suffers from the crosstalk noise. We study use of error correction coding(ECC) and angular multiplexing for digital holographic memory(DHM) system. The analog image is encoded to binary images by ECC. Binary images are stored using angular multiplexing in DHM. The retrieved binary images are decoded by ECC. The bit error-rate is measured for perspective of the DHM system.

• 한국수소및신에너지학회논문집
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• 제24권6호
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• pp.518-523
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• 2013

This paper describes the reduction of a hydrogen sulfide ($H_2S$) generated from a biogas plant. Micro bubble system is adopted to supply air into the water in the reaction chamber, which can increase the contact area of the supplied air to the reserving water. Two stage reaction chambers having two reaction rooms are designed and manufactured to enhance the reduction rate of a hydrogen sulfide. Sodium hydroxide (NaOH) is also considered to get rid of a hydrogen sulfide. Air volume rate to the water in a reaction chamber is maintained between 0.5 and $1.0m^3/min$. Throughout experimental measurement of the concentration of a hydrogen sulfide by changing the volume of supplied air into the water, reduction rate of a hydrogen sulfide increases as air volume increases. Adding sodium hydroxide to the water with the air supply can reduce effectively a hydrogen sulfide up to 99.5% from biogas. It is noted that a hydrogen sulfide generated by a biogas plant can reduce by supplying micro bubble air and sodium hydroxide effectively.

• Current Optics and Photonics
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• 제3권1호
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• pp.27-32
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• 2019

We present an autofocus tracking system implemented by the digital refocusing of digital holographic microscopy (DHM) and the tunability of an electrically tunable lens (ETL). Once the defocusing distance of an image is calculated with the DHM, then the focal plane of the imaging system is optically tuned so that it always gives a well-focused image regardless of the object location. The accuracy of the focus is evaluated by calculating the contrast of refocused images. The DHM is performed in an off-axis holographic configuration, and the ETL performs the focal plane tuning. With this proposed system, we can easily track down the object drifting along the depth direction without using any physical scanning. In addition, the proposed system can simultaneously obtain the digital hologram and the optical image by using the RGB channels of a color camera. In our experiment, the digital hologram is obtained by using the red channel and the optical image is obtained by the blue channel of the same camera at the same time. This technique is expected to find a good application in the long-term imaging of various floating cells.

• Journal of information and communication convergence engineering
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• 제21권1호
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• pp.90-97
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• 2023

Digital holographic microscopy (DHM) is a three-dimensional (3D) imaging technique that uses the phase information of coherent light. In the reconstruction process of DHM, a narrow region around the positive or negative sideband from the Fourier domain is windowed to avoid noise due to the DC spectrum of the hologram spectrum. However, the limited size of the window also degrades the high-frequency information of the 3D object profile. Although a large window can have more detailed information of the 3D object shape, the noise is increased. To solve this trade-off, we propose phase difference averaging (PDA). The proposed method yields high-frequency information of the specimen while reducing the DC noise. In this paper, we explain the reconstruction algorithm for this method and compare it to various conventional filtering methods including Gaussian, Wiener, average, median, and bilateral filtering methods.

• 산업기술연구
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• 제25권B호
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• pp.121-126
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• 2005

Micro wires manufactured by the straightening process are used in the BT(Bio-Technology), IT(Information-Technology), NT(Nano-Technology). We have developed a novel wire straightener which uses the direct heating method(DHM) for straightening the micro wire and shearing device for burr-less cutting. In this study, we confirm the tendency of micro wire after the shearing process. It is impossible to remove the burr in the shearing process. However, the embodiment of minimum burr size after the shearing process is the best in-process method. In order to minimize the burr size, we have accomplished the various experiment condition such as the U-groove, the effect of the counter punch, the shear angle, clearance.

• 생명과학회지
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• 제14권4호
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• pp.553-559
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• 2004

국산 한약재를 이용하여 식품학적 품질 및 기능성이 증진된 전통된장을 개발할 목적으로 여러 종류의 국산 한약재를I∼IV군으로 조합하여 121$^{\circ}C$에서 2시간 동안 추출물을 제조한 다음, 담금용 염수에 여러 농도로 첨가한 후 3개월 동안 자연발효시킨 한방 콩된장의 품질특성을 조사하였다. 한약재 첨가 된장의 일반성분 분석에서 대조구는 수분 61.9%, pH 5.50, 총산도 3.25 ml, 염도 12.6%를 나타내었으나 시험구는 수분 58.2% ∼61.9%, pH 5.32∼5.56, 총산도 3.07∼3.70 ml, 염도 11.7∼13.9%범위로 거의 비슷한 값을 나타내었으며, 환원당, 조단백, 조지방 및 아미노태 질소함량은 대조구보다 약간 높게 나타났다. 지용성 갈변도는 대조구와 큰 차이가 없었지만, 수용성 갈변도는 I군과 II군은 III군과 IV군에서 매우 높은 경향이었다. 한약재 첨가 된장의 색도 측정에서 명도(L)는 대조구 된장(31.72)에 비하여 I군과 II군의 된장이 낮은 수치(24.32∼27.71)를 나타내어 된장의 색깔이 검은 색을 띄었다. 적색도(a)는 제 I군을 제외한 나머지 된장에서는 대조구보다 약간 낮은 값을 나타내었으며, 황색도(b)는 III군과 IV군의 경우 대조구 된장과 비슷하였으나 I군과 II군은 낮게 나타났다.

• 방송공학회논문지
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• 제28권1호
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• pp.55-78
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• 2023

디지털 홀로그래피 현미경을 통해 획득한 간섭무늬는 시료의 두께 정보를 포함하고 있다. 하지만 데이터의 용량이 크다는 단점이 존재한다. 따라서 간섭무늬가 담고 있는 시료의 두께 정보 손상을 최소화하면서 데이터 크기를 줄일 수 있는 압축 방법이 요구된다. 본 논문은 위상 압축 방법을 제시하여 JPEG Pleno Holography에서 사용되는 간섭무늬 압축 방법보다 위상 압축 방법이 더 효율적임을 실험을 통해 확인했다. RMSE와 BD-Rate 그리고 PSNR을 사용하여 평가한 결과 위상 압축 방법이 간섭무늬 압축 방법보다 최고 92.39% 향상된 성능을 보였다. 또한 다양한 조건 아래에서 실험을 진행하여 조건 별 압축 성능을 비교분석 했다. 간섭무늬 압축 방법의 경우 시료의 두께를 계산하기 위한 위상 정보뿐 아니라 다른 정보들도 포함하고 있음에 반해, 위상 압축 방법은 간섭무늬에서 불필요한 정보들을 제거 후 위상에 대한 정보만을 압축하는 방식이기 때문에 더 높은 성능을 보이는 것으로 판단 된다.