• 한국환경과학회지
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• 제27권3호
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• pp.155-165
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• 2018

Observations were conducted in Uiseong Binggye-ri Ice Valley of Korea, where a low temperature talus is located. The talus temperature at Ice Hole near the lower end of the talus remained at $0^{\circ}C$ until summer or autumn and averaged $-0.3^{\circ}C$ over 2 years. The talus temperature at Warm Hole was much higher than the external air temperature during autumn and winter. The outflow of warm air at Warm Hole begins in the late summer of fall. The direction of airflow through the talus surface was determined by the relationship between talus temperature and external air temperature. Annual variations in talus temperature and air exchange between the talus and the external environment can be divided into four periods. It was found that the airflow directions at Warm Hole and Ice Hole were not necessarily opposites. The outflows from the talus at Ice Hole and Warm Hole can occur simultaneously.

• 설비공학논문집
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• 제17권2호
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• pp.156-164
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• 2005

A comparative analysis of an ice storage system has been performed on the operation cost for the four control strategies, i.e., chiller priority and chiller downstream, chiller priority and chiller upstream, storage priority and chiller upstream, storage priority and chiller downstream. Main components of the ice storage system are an ice-on-coil storage tank and a screw compressor chiller. With the simulation program, the operation cost has been evaluated from the economics of an ice storage system. It is found that the operation cost of the ice storage system is strongly dependent on the control strategy, i.e., chiller priority or storage priority, but less affected by the arrangement method, i.e., chiller upstream or chiller downstream. In case of the maximum load day, the control strategy with chiller priority and chiller upstream is supposed to obtain the reduction of operation cost. However, it is found that the control strategy with storage priority and chiller downstream is the best economical operation for most summer seasons except the maximum load day.

• 설비공학논문집
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• 제18권7호
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• pp.571-577
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• 2006

The characteristics of ice packing factor (IPF) at the ice slurry system using one line type are compared with the system using two lines type. The installation space for one transporting line is saved at the one line system. For the one line type, the ice packing factor is reduced along the downstream, but for the two lines type, the ice packing factor is fixed. For the one line system, mass flow rate in the main line is fixed along the down-stream, but for two lines system, the mass flow rate in the main line is reduced along the downstream. For one line system, along the down stream after IPF=0, the temperature at the main steam is increased, and the extracted mass flow is increased. The initial IPF, at which the IPF is not arrived at zero upto the final node, is proposed for the B area.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.633-633
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• 2002

We investigated the distributions of sea ice using various microwave remote sensing techniques in the part of Drake passage, Antarctica, between the area 45-75$^{\circ}$W and 55-66$^{\circ}$S. We used Topex/Poseidon(T/P) radar altimeter, ERS-1 altimeter, ERS-2 scatterometer, Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR), and DMSP Special Sensor Microwave/Imager(SSM/I) data. The sea ice distributions were estimated between May and Jun., 1995 and Oct. and Nov., 1998. The two altimeter measurements (T/P and ERS-1) showed good coherence with the results from the radiometer data in the given period when the ice concentration of 20% and greater was selected. The scatterometer data also showed good correlation with altimetry-implied sea ice surface. The maximum and minimum values of sea ice distribution were appeared in Aug. and Feb., respectively. In general, the sea ice distributions estimated from radar altimeter, radioneter, and scatterometer are well correlated.

• 한국축산식품학회지
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• 제38권6호
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• pp.1216-1225
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• 2018

Shelf-life is defined as the amount of time during which a food product retains its desired sensory, chemical, and physical characteristics while remaining safe for consumption. The food industry needs to rapidly obtain the necessary information for determining the shelf life of its products. Here we studied the approaches available for conducting accelerated shelf-life tests. Accelerated shelf-life testing is applied to a variety of products to rapidly estimate change in characteristics with time. The aim of this work was to use accelerated shelf-life testing to study the changes in pH, microbiology, and sensory characteristics of ice cream by the application of a kinetic approach and, based on the observations, to estimate its shelf life. As per the current law, there is no shelf life on ice cream. Our results suggest that the shelf life of an ice cream sample was 24.27 months at $-18^{\circ}C$, 2.29 months at $-6^{\circ}C$, 0.39 months at $-1^{\circ}C$, and 0.15 months at $4^{\circ}C$. Results of this study suggest that a set expiration date on ice cream might also contribute to effective management of ice cream characteristics in the retail chilled chain.

• 대한설비공학회지:설비저널
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• 제20권2호
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• pp.117-124
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• 1991

• 대한설비공학회지:설비저널
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• 제20권2호
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• pp.104-109
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• 1991

• 한국식품과학회지
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• 제29권2호
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• pp.326-336
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• 1997

INP를 포함한 빙핵활성세균을 식품 가공 단계에 직접 이용하기 위해 빙핵활성을 최대한 유지시키면서 완전 살균하는 방법을 찾기 위해 가열, 고압, 방사선으로 처리한 후 생균수 및 빙핵활성을 측정하였다. 균주는 Pseudomonas syringae, Xanthomonas campestris와 INP유전자를 포함한 plasmid가 재조합된 Escherichia coli JM109/pEIN229, Gluconobacter oxydans/pKIN230를 사용하였다. 빙핵활성을 T90 (drop의 90%가 어는 온도)으로 나타내었을 때 방사선 조사시 $0.3^{\circ}C{\sim}0.7^{\circ}C$, 초고압 처리시 $1^{\circ}C{\sim}2^{\circ}C$, 가열 처리시 $4^{\circ}C{\sim}7^{\circ}C$가 감소하여 방사선 조사에 의한 살균시 빙핵활성의 감소가 가장 적은 것으로 나타났다. 각 살균점에서의 cumulative ice nucleation activity spectra를 측정한 결과 A부류의 빙핵($-5^{\circ}C$ 이상에서 빙핵으로 작용)의 수는 방사선처리시 거의 감소가 없었으며 초고압처리시 90% 이상 감소하였으며 가열처리시 존재하지 않았다. 증류수에 방사선조사로 살균된 빙핵활성세균을 첨가한 후 DSC를 이용해 thermogram을 얻었다. 빙핵활성세균을 첨가하지 않은 증류수보다 $11^{\circ}C{\sim}15^{\circ}C$ 정도 높은 온도에서 발열 피크가 형성되기 시작했으나 흡열 피크는 큰 차이를 보이지 않았으며, 발열량 및 흡열량은 감소했다. 한편, DSC를 이용해 측정된 빙핵활성은 drop freezing method에 의해 측정된 값과 높은 연관성$(R^{2}>0.993,\;p<0.0001)$을 보여 간편하고 정확한 빙핵활성 측정법으로의 사용 가능성을 제시했다.

• Applied Biological Chemistry
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• 제20권2호
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• pp.228-235
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• 1977

산업폐수가운데 유기성폐수로서 설탕, Ice cream 및 맥주공장폐수등 3종을 택하여 그중에 번식하는 유용한 미생물로서 생장도활성이 큰 효모균주를 분리하고 선정균주에 의한 폐수처리실험한 결과 최적조건하($pH\;4.5{\sim}5.5,\;30{\pm}1^{\circ}C,\;O_2\;0.2\;v/v/min.,\;600{\sim}900\;r.p.m.$) 다음과 같은 결과를 얻었다. 1) 분리동정한 Candida curvata는 3종의 식품공장폐수에 배양실험한 결과, 무기영양원 첨가시 생육이 양호하여 폐수처리에 이용가능한 균주이었다 2) 폐수의 멸균조작의 유무는 설탕및 맥주공장폐수의 경우, 배양결과에 큰 차이가 없었으며, 다만 Ice cream공장폐수의 경우 비멸균시 induction period가 훨신 장시간이었다. 3) 비멸균배양시 최대 비증식속도는 설탕, Ice cream 및 맥주공장폐수 순으로 각각 0.5, 0.5 및 1.0/hr이었다. 4) 접종량을 늘리면, 비멸균시에서도 induction period가 짧아지고 따라서 배양시간이 단축되었다. 5) 건조균체량은 설탕, 맥주 및 Ice cream공장폐수 순으로 폐수 $1{\ell}$당 각각 175mg, 628mg 및 857mg이었고, 균체의 조란백함량은 같은 순으로 각각 52%, 54% 및 54%이었다. 6) BOD 제거율은 위의 5)항과 같은 순으로 각각 49%, 80%, 및 64%이었다.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1470-1474
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• 2009

Thermal and photochemistry of methyl iodide ($CH_3I)\;adsorbed\;on\;D_2O$ ice film on Cu(111) at 100 K were studied using temperature-programmed desorption (TPD) time-of-flight mass spectrometry (TOF-MS), X-ray and ultraviolet photoelectron spectroscopies. On the basis of TPD, multilayer and monolayer $CH_3I$ molecules desorb from $D_2O$ ice layer at 120 and 130 K, respectively. Photo-irradiation at 100 K exhibits dramatic changes in the TPD and I $3d_{5/2}\;XPS\;of\;CH_3I$ on ice film, due to a dramatic dissociation of $CH_3I$. The dissociation is likely activated by solvated electrons transferred from the metal substrate during photo-irradiation. No other photo-initiated reaction products were found within our instrumental detection limit. During photo-irradiation, the $CH_3I$, $CH_3$ and I could be trapped (or solvated) in ice film by rearrangement (and self-diffusion) of water molecules. A newly appeared parent molecular desorption peak at 145 K is attributed to trapped $CH_3I$. In addition, the $CH_3$ and I may diffuse through ice and chemisorb on Cu(111), indicated by TPD and I $d_{5/2}$ XPS taken with photo-irradiation time, respectively. No molecular ejection was found during photo-irradiation at 100 K. The work functions for $CH_3I/Cu(111),\;D_2O/Cu(111)\;and\;CH_3I/D_2$O/Cu(111) were all measured to be about 3.9 eV, 1.0 eV downward shift from that of clean Cu(111).