• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1466-1473
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• 2013

This experiment was conducted to study the variation laws and correlations of shearing force and feed characteristics including morphological characteristic, chemical composition and in situ degradability of wheat straw. Feasibility of evaluating the nutritional value of wheat straws with shearing force values was analyzed in this study. Six hundred wheat straw plants (Jimai 22) were randomly selected and placed in a cool and ventilated place. Samples were collected in the 1st, 15th, 30th, 45th, 60th d after harvest to measure shearing force, morphological characteristic, nutritional composition. Rumen degradation of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of wheat straws were determined by the nylon bags method. The results demonstrated that linear and quadratic effects of storage time on all the tested morphological characteristics were significantly correlative (p<0.01). As storage time goes on, all the tested nutrients and their rumen degradations of wheat straw was linearly (p<0.01) and quadratic (p<0.01) correlative except ADF content and rumen degradation of ADF. Significant correlations were determined in linear effect of shearing force on morphological characteristics (p<0.01), and linear density and diameter were a more sensitive predictor than stem thickness for shearing force. There were strong correlations between storage time and all the measured physical characteristics (shearing force, morphological characteristics and shearing force standardized by morphological characteristics) (p<0.01). Nutrition compositions were linearly correlative with shearing force and standardized shearing force (p<0.01). The linear correlation between rumen degradation of DM and NDF and shearing force and standardized shearing force were evident (p<0.01). In conclusion, shearing force, nutrition compositions and their rumen degradation of wheat straw were still dynamic with storage time after harvest. Correlation could be found between shearing force and nutritional characteristics of wheat straw. Nutrient content, morphological index and rumen degradation of DM and NDF could be predicted by changes in shearing force. Shearing force should be applied according to a standardized storage time when it is used to forecast the feed value of wheat straws.

• 한국가스학회지
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• 제12권1호
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• pp.31-35
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• 2008

압축천연가스 자동차는 최근 대기환경 개선을 위해 대도시 시내버스에 적용되고 있으며 대기 오염물질을 저감시키는데 효과적인 것으로 입증되고 있다. 압축천연가스의 단점인 낮은 연료저장밀도를 높이기 위해 액화천연가스를 연료로 하는 차량기술이 시도되고 있다. 본 논문에서는 자동차에 액화 천연가스를 적용하기 위한 LNG 저장 용기의 단열특성을 실험적으로 측정하여 기준과의 적합성을 판단하였으며 측정방법에 대한 비교검토를 통해 측정결과의 신뢰성을 제고하였다. 시험용기의 단열성능계수는 $40J/h{\cdot}^{\circ}C{\cdot}m^2$으로 기준범위 이내의 성능을 확인하였으며 두 가지 측정방법들은 상호 일치하는 결과를 보여주었다. 또한 용기의 벤트밸브 동작특성을 조사하여 증발가스의 방출량 특성을 파악하였다.

• 조명전기설비학회논문지
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• 제22권1호
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• pp.66-72
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• 2008

최근 한약재의 저장 중 품질 유지를 위한 다양한 방안이 검토되고 있으며, 그 방안의 하나로 한약재의 유해 세균 및 잔존 농약을 분해, 처리하여 저장하는 방법을 연구하였다. 오존발생기에 관한 선행 연구를 통해 오존이 박테리아 및 비루스에 대한 살균효과가 우수함을 확인하고, 오존을 이용하여 한약재 살균처리 및 저장(이하 OPS)에 적용하는 방법을 연구하였다 본 연구에서는 현재 시중에 많이 유통되어 사용되고 있는 4종류의 약재를 선정하여 한약재 특성 평가를 실시하였다. 즉 오존 램프를 이용하여 한약재 살균 특성을 조사하였고, 장기간 오존 저장 후 한약재의 품질 및 고유 성분이 유지되는지를 조사하기 위하여 한약재의 일반성분 및 생리활성물질의 정량분석 평가를 하였다.

• 한국식품영양과학회지
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• 제30권5호
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• pp.854-857
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• 2001

본 연구는 ESR spectroscopy를 이용하여 free radical 농도를 측정함으로써 건조채소류의 방사선 조사여부를 일정기간 후에도 확인할 수 있는 지를 알아보았다. 라면의 수프에 이용되고 있는 건조된 당근, 표고버섯 및 파를 선택하여 0, 1, 3, 5 및 7 kGy로 Co-60 감마선을 조사한 후, 이를 시료로 Bruker-EPR Spectroscopy를 이용하여 측정하였다. 실험결과 방사선 조사직후에는 조사된 건조 당근, 표고버섯 그리고 파에서 라디칼의 특성신호를 나타내어 비조사시료와 뚜렷하게 구별되었다. 더욱이 적용선량의 범위에서(1~7 kGy) 조사선량이 증가함에 따라 free radical의 농도는 비례적으로 증가하였으며, 선량의 증가에 따른 free radical의 농도의 증가를 나타낸 $R^2$ 값은 0.9747~0.9919의 높은 값을 나타내었다. Free radical의 농도는 저장기간이 경과함에 따라 다소 감소하였으나 4주 이후부터는 감소량이 적었다. 또한 이들 신호는 12주간의 저장기간 후에도 관찰할 수 있어 ESR spectroscopy를 이용한 건조채소류의 방사선 조사여부 판별은 3개월간의 저장후에도 측정 가능한 방법임을 알수 있었다.

• 한국식품조리과학회지
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• 제18권2호
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• pp.129-135
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• 2002

한국산 대두(장엽콩)에 녹차가루를 첨가하여 제조한 두부의 저장 특성을 검토하였다. 녹차가루 첨가 두부의 수율은 첨가량이 증가할수록 낮은 수율을 보였다. 녹차가루 첨가두부와 두부 침지액의 pH는 저장기간동안 감소하는 경향을 보였으며, pH 감소폭은 녹차가루를 첨가하지 않은 시료에서 가장 컸고, 녹차가루 1.0% 첨가시료에서 가장 적었다. 녹차가루 첨가두부 색도에서, 적색도를 나타내는 a값은 저장에 따라 증가하는 경향이었으나 L값과 b값은 큰 변화를 보이지 않았다. 녹차가루 첨가두부의 조직 특성치는 저장기간에 따라 큰 변화는 보이지 않았다. 저장기간이 경과함에 따라 녹차가루 첨가두부 침지액의 총 미생물 수와 흡광도는 증가하였으며, 녹차가루 첨가량이 증가함에 따라 수치가 낮아져 저장 8일째의 녹차가루 1.0% 첨가시료의 미생물은 3.0x$10^{6}$ CFU/ml이었으며 흡광도는 0.175로 가장 낮았다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1158-1158
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• 2001

Fast and dynamic biochemical, enzymatic and morphological changes occur during the so-called generative development and during the vegetative processes in seeds. The most characteristic biochemical and compositional changes of this period are the formation and decline of storage components or their precursors, the change of their degree in polymerization and an extensive change in water content. The aim of the present study was to detect the maturation processes in seed nondestructively and to verify the applicability of near infrared spectroscopic methods in the measurement of physiological, chemical and biochemical changes in wheat seed. The amount and variation of different water “species” has been changed intensively during maturation. Characteristic changes of three water absorption bands (1920, 1420 and 1150 nm) during maturation were analysed. It was concluded that the free/bound transition of water molecules could be followed sensitively in different region of NIR spectra. Kinetic changes of carbohydrate reserves were characteristic during maturation. An intensive formation and decline of carbohydrate reserves were observed during early stage of maturation (0 -13 days, high energy demand). An accelerated formation of storage carbohydrates (starch) was detected in the second phase of maturation. Five characteristic absorption bands were analysed which were sensitive indicators the changes of carbohydrates occurred during maturation. Precursors of protein synthesis and the synthesis of reserve proteins and their kinetic changes during maturation were followed from NIR spectra qualitative and qualitatively. Dynamic formation of amino acids and the changes of N forms were detected by spectroscopic, chromatographic and by capillary electrophoresis methods. Calibration equations were developed and validated in order to measure the optimal maturation time protein and moisture content of developing wheat seeds. The spectroscopic methods are offering chance and measurement potential in order to detect fine details of physiological processes. The spectra have many hidden details, which can help to understand the biochemical background of processes.

• 동아시아식생활학회지
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• 제25권3호
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• pp.484-491
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• 2015

This study investigated the quality variation characteristics of Ssamjang containing Cheongkukjang, in order to improve the degree of preference of Cheongkukjang. The amount of Cheongkukjang was set at 1% based on sensory evaluation. Ssamjang containing Cheongkukjang was stored at $37^{\circ}C$ for 13 weeks, after which quality variation characteristics were weekly. During storage for 13 weeks, physicochemical quality characteristics, moisture content, and pH of Ssamjang containing Cheongkukjang slightly decreased, whereas salt content did not change. Amino nitrogen content slightly increased by 1 week but decreased by 3 weeks and then increased by 5 weeks. For microbiology quality characteristics, viable cell counts and total cell counts of B. cereus were unchanged. For sensory quality characteristics, shape quality was poor after 13 weeks while mold, drying phenomenon, and swelling phenomenon were not observed. Therefore, physicochemical quality and microbiology quality of Ssamjang containing Cheongkukjang were unchanged during storage for 13 weeks, and the storage limit was determined to be 12 weeks according to sensory quality evaluation.

• 산업공학
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• 제13권4호
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• pp.658-667
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• 2000

Seasonal variation of natural gas demand coupled with rigid and stable import pattern of gas represents the characteristic feature of the Korean Liquified Natural Gas(LNG) industry. This attribute has required a huge amount of investment for the construction of storage facility. Thus, to minimize the supply cost, it is legitimate to reduce storage requirement itself. In this study, we combine three alternative methods to deal with the storage requirement to minimize the supply cost. Those are (1) adding additional storage tanks, (2) inducing large firm customers, and (3) constructing gas-turbine self generation facilities. Methodologically, we employ the mixed integer program (MIP) to optimize the system. The model also consider demand and price-setting scheme in separate modules. From the results, it is shown that if alternatives are combined optimally, a number of storage tanks can be reduced substantially compared with the original capacity plan set by the industry authorities. We perform various sensitivity analyses to check the robustness of the results. The methodology presented in this study can be applied to the other physical network industry, such as hydraulics. The empirical results will shed some light on the rationalization of capacity planning of the Korean natural gas industry.

• 한국초전도ㆍ저온공학회논문지
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• 제25권4호
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• pp.65-69
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• 2023

Hydrogen is an eco-friendly energy source and is being actively researched in various fields around the world, including mobility and aerospace. In order to effectively utilize hydrogen energy, it should be used in a liquid state with high energy storage density, but when hydrogen is stored in a liquid state, BOG (boil-off gas) is generated due to the temperature difference with the atmosphere. This should be re-condensed when considering storage efficiency and economy. In particular, large-capacity liquid hydrogen storage tank is required a gaseous helium circulation cooling system that cools by circulating cryogenic refrigerant due to the increase in heat intrusion from external air as the heat transfer area increases and the wide distribution of the gas layer inside the tank. In order to effectively apply the system, thermo-hydraulic analysis through process analysis is required. In this study, the condenser design and system characteristics of a gaseous helium circulation cooling system for BOG recondensation of a liquefied hydrogen storage tank were compared.

• Asian-Australasian Journal of Animal Sciences
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• 제22권3호
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• pp.428-432
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• 2009

40 goat kid ribcages were held for 7 days in storage conditions ($4^{\circ}C$) and used to determine the effects of three different packaging methods (atmospheric air, vacuum and modified atmosphere package (MAP) 10:70:20 mixture of $N_2:O_2:CO_2$) on meat quality of the chops. L* was affected by the packaging method being lighter than MAP chops. The coordinate a* significantly increased during storage time. For MAP-packed chops and those kept in atmospheric air, b* increased markedly during storage time whereas it remained unaffected throughout storage when in vacuum packages. Final pH values ranged from 5.6 to 5.8 and no effects were found for either storage time or packaging method. WHC means were lowest for the three packaging methods on day 7 of storage and highest on day 1. Storage time increased water loss in vacuum treatments. Trained panel colour acceptability was lower at 3, 5 and 7 days than on day 1 of storage for atmospheric air treatment and vacuum packaging, while for the MAP treatment average values on days 5 and 7 were lower than those observed on days 1 or 3. Trained panel odour was lower for atmospheric air and vacuum packages at 3, 5, and 7 days storage than at 1 day, while no differences were found in trained panel odour acceptability for MAP packages. With reference to consumers, the MAP proposed in the present study is the chosen method for storing goat meat, rather than vacuum or atmospheric air packaging.