• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.165-170
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• 2013

In spatial, desired target direction of arrival estimation is to find a incidental signal direction on receive antennas. In this paper, we were an estimation a desired target direction of arrival using maximum likelihood method. Direction of arrival estimation method estimated a desired target calculating the maximum likelihood sensitivity using singular value decomposition above threshold signals among receive signals in maximum likelihood method. Through simulation, we were analysis a performance to compare existing method and proposal method. In direction of arrival estimation, proposed method is effectivity to decrease processing time because it is not doing an eigen decomposition in direction of arrival estimation, and desired target correctly estimated. We showed that proposal method improve more target estimation than general method.

• 한국지형공간정보학회:학술대회논문집
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• 2002.03a
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• pp.17-22
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• 2002

인공위성을 이용한 위치결정시스템인 GPS(Global Positioning System)는 mm 단위의 정밀도로 정적, 동적 위치관측이 가능한 시스템으로 현재 여러 분야에서 활용이 증가하고 있다. 특히 교량, 댐 등 안전이 요구되는 사회기반 시설물의 동적 거동을 기록하고 감시하는데 있어서 GPS가 새로운 관측시스템으로 주목받고 있으며 이를 실용화하기 위한 연구가 활발히 진행되고 있다. 본 연구에서는 GPS를 이용하여 건물의 거동상태를 점검 하는 것을 목적으로 하고 있다. 계절풍에 의한 초고층건물의 거동을 해석하기 위하여 건물 옥상에 GPS, 가속도계, 풍향계, 풍속계를 설치하였다. GPS와 가속도계로를 이용하여 건물의 변위 및 가속도를 5Hz로 관측하였다. GPS를 이용한 변위관측은 1시간, 1분, 1초 등의 간격으로 3차원 변위를 계산하였으며, 계산된 3차원 변위를 가속도계, 풍속계, 풍향계와 연계하여 해석하였다. 대상 건물에 대한 최대 변위를 관측한 결과 계절에 따라 큰 차이를 보였으며 건물의 안정성을 평가할 수 있는 척도인 건물의 고유 진동수의 경우 약 0.2Hz의 값을 얻을 수 있었다. 향후 모든 센서들을 통합하여 실시간으로 건물을 모니터링할 수 있는 시스템을 개발할 경우 건물의 안정성 해석 및 유지보수에 본 연구가 큰 기여를 할 수 있을 것으로 사료된다.

• Journal of the Mineralogical Society of Korea
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• v.1 no.1
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• pp.20-31
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• 1988

울진 연.아연 광사의 Ca석류석은 결정화학적 성질의 차이에 따라 색, 경도, 비중과 같은 물리적 특성이 달라진다. 가기 다른 색을 보여주는 네가지의 석류석에 대하여 전자현미분석, X-선 회절분석, 뫼스바우어 및 적외선 분광분석등을 실시하여 화학적, 구조적 및 결정화학적 특징을 연구하였으며 광학적 및 물리적 특성도 연구되었다. 화학분석에 의하면 Fe 함량이 0.35에서 1.92%로 증가함에 따라 석류석의 색이 연분홍, 황록색, 적갈색 및 암갈색의 순으로 변한다. 이러한 Al에 대한 Fe의 치환은 단위포의 크기에도 영향을 미쳐 11.91$\AA$에서 12.06$\AA$으로 단위포의 크기가 증가한다. 뫼스바우어 계수에 따르면 Fe치환에 따른 Y-O 거리의 증가로 $\delta$값이 0.372에서 0.389mm/sec로 일정하게 증가한다. 또한 능을 고유하며 이웃하는 X십이면체에 영향을 주어 내부대칭도를 떨어뜨리게 된다. 이러한 현상은 적외선 스펙트럼의 360~300cm-1의 영역에서 그로슐라에는 관찰되지 않는 수개의 흡수선이 안드라다이트에서는 관찰된다. 한편 소량의 Fe2+가 그로슐라에서만 관찰됨을 미루어 석류석의 생성이 용역내으 낮은 산소분압에 영향을 받았을 것으로 추측된다.

• Food Science and Preservation
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• v.23 no.3
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• pp.310-318
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• 2016

This study was performed to investigate changes in the quality characteristics and chemical compounds in garlic shoots by blanching for different time (0, 0.5, 1, 2, 3, and 4 min). The color (L, a, and b values), texture profile (hardness, springiness, chewiness, gumminess, and cohesiveness), total vitamin C, total sugar, total polyphenol and flavonoid, chlorophyll a and b contents, total pyruvate and thiosulfinate contents of the blanched garlic shoots were examined. As the blanching time increased, the L and b values decreased, while the a value increased. Hardness, chewiness, springiness and gumminess of the blanched shoots were significantly lowered with the increasing blanching time. Vitamin C content of raw garlic shoot was 1.62 mg/100 g while that of the blanched garlic shoots was 0.16~0.24 mg/100 g, implying vitamin C loss into blanching water and destruction by heat. The total sugar and polyphenol contents were fluctuated during blanching, but over 75% of their initial levels were retained under all blanching conditions. The total flavonoid contents increased as the blanching time increased. The chlorophyll a content did not show significant change with blanching time, but the chlorophyll b content significantly decreased. These results suggest that blanching for 2 min could be the best for retaining beneficial compounds and desirable quality of garlic shoot.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.90-99
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• 2014

Tarak is our own traditional fermented milk, which is made from lactic acid fermentation by using makgeolli as inoculum for milk or fermented by using Tarak that had already made. we made our own traditional fermented milk and Tarak Pudding by the traditional fermented milk, and then, we investigated the quality characteristics of Tarak Pudding on the addition rates of Tarak. As a result, the more the amount of Tarak, the more the contents of crude protein, crude fat and crude ash of Tarak Pudding according to the percentage of addition of Tarak meaningfully, except for its moisture content (p<0.05). While the pH decreased with more Tarak, the acidity significantly increased. In the case of sugar content, TP 1, 2, and 3 were higher than the control group, and TP 4 showed the higher sugar content(p<0.05). As the result of measurement of chromaticity of Tarak Pudding, the L value of the control group was 38.80. However, it increased with more addition of Tarak, while a value decreased. For the b value, it significantly increased with more Tarak. In the measure of texture, there were significant differences between the control group and the samples in hardness, springiness, cohesiveness, chewiness, and adhesiveness (p<0.05). The sensory evaluation result showed that there were meaningful differences among the samples in their appearance, taste, flavor, texture and overall acceptance. However, due to distinctive sour and odor of Tarak, TP 3 (75% addition) than TP 4 (100% addition) was considered to be desirable.

• Journal of the Korea Concrete Institute
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• v.13 no.4
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• pp.336-345
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• 2001

The construction of underwater structures has been increased, but underwater concrete hassome problems of quality deterioration and contamination around in-situ of civil and architecture; therefore, new materials and methods for them are demanded. In this paper in-situ application of underwater antiwashout concrete which is manufactured for trio purpose of not only decreasing suspended solids and the heat of hydration but also increasing long term strength was studied. In the case of mock-up test(Ⅰ), when underwater antiwashout concrete, whose slump flow was 58 cm, was placed in the mock-up test at a speed of 24 ㎥/hr, it took about a minute to flow to the side wall, and the surface was maintained at horizontal level. In this case, compressive strength of the core specimens in each section was higher than the standard design compressive strength of 240 kgf/㎠. In the case of mock-up test(II), pH value and suspended solids of high strength underwater antiwashout concrete were 10.0∼11.0 and 51 mg/ℓ at 30 minutes later, initial and final setting time were about 30, 37 hr, and the slump flow of that was 53$\pm$2 cm. In the placement at a speed of 27 ㎥/hr, there was no large difference in flowing velocity, with or without reinforcement and flowing slope was maintained at horizontal level. In this case, compressive strength and elastic modulus of the core specimens somewhat decreased as flowing distance was far : however, those of central area showed the highest value.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.56-56
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• 2023

남양호는 농업용수 공급을 위해 건설된 하구 담수호로 과도한 영양물질 축적으로 인해 매년 여름 녹조류가 번성한다. 따라서 본 연구에서는 조류발생 특성을 분석하고자 식물성 플랑크톤 및 관련 분해 산물에 의해 고유 광학특성을 가지고 있는 Chlorophyll-a(Chl-a)의 추정을 통한 녹조 발생을 파악하고자 Sentinel-2 Multi Spectral Image(MSI)의 원격 반사율 광학 스펙트럼을 사용하였다. Chl-a 추정알고리즘 개발을 위하여 Sentinel-2 A, B의 교차 방문주기인 5일 간격에 맞추어 현장수질자료(2022년: 27회 2023년: 27회)를 측정하였다. Chl-a 농도는 EXO-YSI를이용하여 측정하였으며 해당기간동안 9.4 ~ 127.1 mg/L의 범위를 보였으며, Sentine-2 자료는 A, B자료에서 B1(443 nm) ~ B8A(865 nm)파장의 값을 기상조건(구름, 안개, 강수)을 고려하여 현장수질측정 위치에서 반사도를 추출하였다. 입력자료는 대기 및 방사영향을 고려해 반사도 간의 비율자료와 선행연구에서 활용된 반사도를 활용하였으며 알고리즘은 다중선형회귀분석(Multi Linear Regression Model)과 Random Forest를 활용하였다. MLR의 경우 결정계수(R2)가 학습 및 검증에서 각각 0.68, 0.59의 성능을 보였으며, RF의 경우 각각 0.94, 0.85의 성능을 보였다. 해당알고리즘으로 생성된 Chl-a 시공간농도 자료는 담수호내 조류발생 특성을 분석하고 효율적 조류관리 및 대처에 활용될 것으로 판단된다.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.352-360
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• 2010

This study was performed to develop a Korean natural cheese with traditional medical wine, making it different from foreign natural cheese. The effects of cheese with Sasam(Codonopsis lanceolate) wine(CLW) on the quality properties during the ripening period of natural cheese were investigated. The properties investigated were growth of lactic acid bacteria, characteristics of ripening, and sensory characteristics. Four vats of cheese were made on the same day from the same tank of fresh milk. Cheese samples were prepared with CLW at 2.0%, 4.0% and 6.0% of raw milk. Changes in gross composition, viable cell counts, pH, water soluble nitrogen(WSN), non casein nitrogen(NCN), non protein nitrogen(NPN), and proteolysis during maturation were measured. Polyacrylamide gel electrophoresis(PAGE) patterns were determined with control cheese. Viable cell counts of control and CLW cheese were not significantly different. The pH of CLW cheese increased gradually during maturation, and saponin levels and levels of NPN, NCN, and WSN were higher in CLW cheeses than control cheese. For most compositional data, the 4.0% CLW cheese was most similar to the control cheese. The PAGE pattern of cheese caseins indicated that the CLW cheeses degraded more rapidly than the control cheese. Control and 2.0% CLW cheese had good sensory scores, while scores for 4.0% and 6.0% CLW cheese were lower. However, sensory data depreciated with added levels of CLW, especially at a level of 4.0% or more. Further studies on levels of CLW and processing methods are required to improve sensory quality.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.325-333
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• 2007

One bacterium with high proteinase production and spore-forming ability was isolated from korean traditional soybean paste(doenjang). The isolated strain was identified as Bacillus subtilis, based on gram-staining, biochemical properties and l6S rRNA gene sequencing, and designated as B. subtilis DJI. Its growth rate was very fast, and it reached its stationary phase within 9 h, and then started to form spores. Bacterial-koji and doenjang were prepared using B. subtilis DJI. Chemical components of the doenjang were determined after 2 months of aging period: amino nitrogen 507 mg%, crude protein 14.3%, crude fat 4.8% and water 54.9%. The composition of total and free amino acids and their ratios of doenjang were changed during the aging period. Among total amino acids in DJI doenjang, glutamic acid, aspartic acid, leucine and arginine were the major amino acids. The fibrinolytic activities of DJI doenjang and traditional doenjangs were 909.7 units/ml and $363.3{\sim}618.6\;units/ml$, respectively. Flavor compounds of DJI doenjang and traditional doenjang were extracted by SDE(simultaneous steam distillation and extraction), and analyzed by GC/MS; DJI doenjang possessed the typically favorable flavor compounds in traditional korean doenjang, with reduced off-flavor compounds.

• The Korean Journal of Food And Nutrition
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• v.24 no.2
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• pp.159-165
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• 2011

This study was carried out to investigate the quality characteristics of pear jam containing fresh ginger(G1) and ginger powders; dried ginger powder(G2), freeze-dried ginger powder(G3), and hot-air dried ginger powder(G4). The moisture, crude protein, and crude ash content of the control group were significantly higher than those of the experimental groups (p<0.001, p<0.05, p<0.01). The pH of the dried ginger powder added jam(G2) was the lowest(p<0.05). Texture profile analysis found that the dried ginger powder added jam(G2) had the highest firmness, consistency, cohesiveness, and resistance to flow/viscosity among all samples(p<0.001). Regarding the spread-meter value of the pear jam, the control group (G1) and hot air-dried ginger powder added jam(G4) had the highest values. The dried ginger power added jam(G2) had the lowest value among the samples(p<0.01). Regarding the color values of the pear jam, the control group(G1) had the highest L and b values. Hot-air dried ginger powder added jam(G4), on the other hand, had the lowest(p<0.001). The opposite was true for a value: hot-air dried ginger powder added jam(G4) had the highest. From the sensory evaluation, a positive trend was observed for the appearance of the dried ginger powder added jam(G2)(p<0.001). For sweetness, the dried ginger powder added jam(G2) had the highest value. A positive trend was observed for the overall acceptability of the dried ginger powder-added jam(G2)(p<0.001). Therefore, the dried ginger powder-added sample(G2) seemed to be the most appropriate to make pear jam with high acceptability.