• 한국식품영양과학회지
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• 제23권3호
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• pp.459-465
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• 1994

Performance of a continuous cocurrent supercritical fluid extraction column for processing of anhydrous milk fat (AMF) was determined. The extract loading increased and the extraction yield decreased as the superficial velocity of AMF increased. The maximum solubility of AMF in $CO_2$ at 4$0^{\circ}C$/3,500 psig was 0.0195g/g. The increase of the carbon dioxide density enhanced the solubility of milk fat and decreased the cholesterol concentration in the extract. Three operation conditions, such as recycle , reflux, and temperature gradient of extraction column, were tested. More short-chain fatty acvids were extracted by the reflux operation . Longchain fatty acids and thehighest ratio fo long-chain unsaturated to saturated fatty acids were also obtained in the raffinate phase with refluex.

• 한국식품영양과학회지
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• 제35권10호
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• pp.1439-1443
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• 2006

들깨분말을 초임 계 이산화탄소로 추출온도, 압력, 시간을 달리하여 추출한 들기름과 토코페롤의 추출수율, 색도 및 지방산 조성을 측정하였다. 초임계 이산화탄소에 대한 지방과 토코페롤의 추출수율은 이산화탄소의 밀도 증가에 따라 증가하였는데, 추출온도보다는 추출압력에 의하여 크게 좌우되었다. 초임계 이산화탄소의 추출온도에 대한 토코페롤의 추출수율은 동일 압력에서 추출온도의 증가에 따라 증가 하였다. 들깨분말을 $40^{\circ}C/276$ bar에서 $60\sim180\;min$ 추출시 간을 달리하였을 때 들기름의 추출수율은 추출시간이 증가함에 따라 급격히 증가한 반면 토코페롤은 감소하였다. 또한 이산화탄소의 밀도가 증가할수록 Red/Yellow값은 증가하였다. 초임계 이산화탄소 추출을 통해 얻은 들기름의 지방산 조성은 추출시간의 증가에 따라 불포화지방산들은 많이 추출되었고, 포화지방산들은 감소되었다. 이는 초임계유체 추출시 지방산의 불포화도가 높아질수록 용해도가 증가하기 때문으로 사료된다. 위 결과는 초임계이산화탄소를 이용하여 천연물로부터 식품이나 의약산업에 중요한 특정물질을 추출할 수 있는 가능성을 보여주고 있으며, 추출물에 잔존하는 유기용매가 없기 때문에 직접 식품가공에 이용할 수 있다.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.847-852
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• 2007

This study investigated an efficient method for the extraction of astaxanthin from the red yeast Xanthophyllomyces dendrorhous. The extraction process comprised three steps: 1) cultivating the yeast; 2) treating the yeast culture suspension with microwaves to destroy the cell walls and microbodies; and 3) drying the yeast and extracting the astaxanthin pigment using ethanol, methanol, acetone, or a mixture of the three as the extraction solvent. Ultimately, various treatment tests were performed to determine the conditions for optimal pigment extraction, and the total carotenoid and astaxanthin contents were quantified. A frequency of 2,450 MHz, an output of 500 watts, and irradiation time of 60 s were the most optimum conditions for yeast cell wall destruction. Furthermore, optimal pigment extraction occurred when using a cell density of 10g/l at $30^{\circ}C$ over 24 h, with a 10% volume of ethanol.

• 한국임상수의학회지
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• 제27권1호
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• pp.55-61
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• 2010

Tooth restoration with implant placement have been interested in modern veterinary dentistry. It is important to reduce the interval between the tooth extraction and the insertion of the implants, to determine the restoration time after implant placement in dogs The aim of the this study was to compare the bone mineral apposition rate of immediately loaded implants with an unloaded control during the early healing state in the artificial extraction mandible. In four Beagles, two premolar sockets (PM2 and PM3) of the both sides of the mandible were installed with a one stage titanium mini-implant with a length of 11 mm and a diameter of 3.37 mm immediately after tooth extraction. Provisional restroration was given to implants, 3 weeks after implant placement in the left side (immediate loading) and 12 weeks in the right side (delayed loading), respectively. Radiographic and histologic examinations were performed. Radiographic evaluation revealed no significant difference between two groups. Bone-implant contact was $47.1{\pm}8.9$ in immediate loading and $50.2{\pm}8.2$ in delayed loading, interthread bone density was $78.7{\pm}10.9$ in immediate loading and $73.1{\pm}15.5$ in delayed loading, and peri-implant bone density was $95.4{\pm}7.1$ in immediate loading and $95.0{\pm}5.2$ in delayed loading, respectively. Three histologic analyses showed no significant difference between delayed and immediate loading. Followed by this study, the immediate loading of implants insterted into fresh extraction sockets after tooth extraction could be considered in veterinary dentistry.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.159-162
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• 1998

Land cover and land use classification on a huge scale, e.g. national or continental scale, has become more and more important because environmental researches need land cover: And land use data on such scales. We developed a crop field extraction method, which is one of the steps in our land cover classification system for a huge area. Firstly, a crop field model is defined to characterize "crop field" in terms of NDVI value and textual information Textual information is represented by the density of straight lines which are extracted by wavelet transform. Secondly, candidates of NDVI threshold value are determined by "scale-space filtering" method. The most appropriate threshold value among the candidates is determined by evaluating the line density of the area extracted by the threshold value. Finally, the crop field is extracted by applying level slicing to Landsat TM image with the threshold value determined above. The experiment demonstrates that the extracted area by this method coincides very well with the one extracted by visual interpretation.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2007년도 춘계학술발표회 논문집
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• pp.379-382
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• 2007

Laser scanning technology with high positional accuracy and high density automation will be widely applied in vast range of fields including geomatics. Especially, the development of laser scanning technology enabling long range information extraction is increasing its full use in civil engineering. The purpose of this study is to extract accurate highway geometric information taking the advantages of scanning technology. Fulfilling this goal, the information of target highway's three-dimensional data was obtained through terrestrial laser scanning technology. In accordance with the result from target highway's geometric information extraction using the information above, laser scanning technology showed faster speed and better accuracy on highway geometric information extraction with reduced cost compared to traditional methods.

• 한국식품영양학회지
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• 제4권1호
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• pp.61-68
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• 1991

In order to study the extraction mechanism of barley tea, some factors affecting extraction and physical properties of roasted barley and extract were examined. The main results of this study are as follows : 1. The roasted barley particles used as the raw materials were amorphous. Under the extraction condition used the average swelling ratio of the particles and imbibed volume were 1. 3g and 1.65ml/g respectively. The maximum soluble solid content in the roasted barley was 67.07%. 2. The concentrations of the barley extracts were determined by measuring their optical densitis at 420nm and the relationship between the concentration(C) and optical density(O. D.) was expressed as : C=6, 178XO. D. As shown in the following relationship, the viscosities(u: Ns/m2) of barley extracts were Influenced by concentration(C : kg/m3) and temperature(T : C). $\mu$=5.6731$\times$$10^{-4}e^{2.7}^{\times10^{{-3}\times{C}}$$\mu$=3.577$\times$$10^{-3}e^{{-3.02}\times{10^{-2}\times{T}}$

• 에너지공학
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• 제2권1호
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• pp.68-74
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• 1993

본 연구에서는 감압잔사유의 활용을 극대화하는 것을 목적으로 초임계 용매 추출법을 이용하여 탈아스팔트오일을 추출하였다. 초임계 용매로 n-pentane을 사용하였으며 온도와 압력 변화에 따른 추출수율과 추출된 오일 중 금속성분 및 황성분 함량의 변화가 조사되었다. 탈아스팔트오일의 추출수율은 사용한 용매의 초임계 영역에서 밀도에 크게 좌우됨이 조사되었고 추출유의 금속성분 함량은 감압잔사유에 비하여 크게 제거되었으나, 황성분 제거율은 낮았다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권3호
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• pp.238-247
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• 2005

The placement of different graft materials and/or the use of occlusive membranes to cover the extraction socket entrance are techniques aimed at reducing alveolar ridge resorption and enhancing bone formation. However, in spite of its clinical advantage, the use of graft materials in fresh extraction socket has been questioned because particles of the grafted material have been found in alveolar sockets with fibrous union. The purposes of this study were to evaluate whether alveolar ridge resorption following tooth extraction could be reduced and bone formation could be enhanced by the application of absorbable gelatin spongy or gelatin spongy soaked with platelet rich plasma(PRP) used as a space filler in clinical and radiographic aspects. Eighty patients who were scheduled for extraction of both third molars were participated and carried out by one experienced surgeon. Following extraction of teeth, one extracted socket were treated with gelatin spongy as an experimental group A and the other were treated with gelatin spongy and PRP as an experimental group B. The routine extracted socket were healed without any treatment as a control group. From the period of extraction to 12 weeks postoperatively, we examined the clinical course and radiographic evaluation on socket at regular interval. Both experimental groups showed faster wound healing process than control clinically. Vertical gingival height of the extraction socket were less changed statistically in both experimental groups than control. The horizontal width change of the extraction socket were not significant statistically in any group. Radiographic changes of the alveolar bone height were less changed in both experimental groups and bone density were showed higher than control. There were a little difference between experimental group A and B. In conclusion, absorbable gelatin sponge and with PRP were considered as having preservation effects of extraction socket and stimulation of bone formation process after extraction.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권9호
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• pp.547-553
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• 2003

In this paper, we designed the PC-based analyzer of the power spectral density that could estimate the heart rate variability from time series data of R-R interval. The power spectral density estimated that it applied the autoregressive model to the measured electrocardiogram during a short period. Also, the characteristics of the designed analyzer are that it could process of the signal filtering, the generation and recomposition of time series and the feature extraction at the same time. Especially the analyzer reconstructed which applied the lowpass filter of the time series composed by the linear interpolation so as to enhance the signal-to-noise feature. We could estimate the power spectral density that confirmed a variety of power peak with low frequency range and high frequency rang of autonomic nerve by the heart rate variability.