• Geomechanics and Engineering
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• 제22권3호
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• pp.219-226
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• 2020

Unconfined compression test (UCT) is widely conducted in laboratories to evaluate the mechanical behavior of frozen soils. However, its results are sensitive to the initial conditions of sample creation by freezing as well as the end-surface conditions during loading of the specimen into the apparatus for testing. This work compared ice samples prepared by three-dimensional and one-dimensional freezing. The latter created more-homogenous ice samples containing fewer entrapped air bubbles or air nuclei, leading to relatively stable UCT results. Three end-surface conditions were compared for UCT on ice specimens made by one-dimensional freezing. Steel disc cap with embedded rubber was found most appropriate for UCT. Three frozen materials (ice, frozen sand, and frozen silt) showed different failure patterns, which were classified as brittle failure and ductile failure. Ice and frozen sand showed strain-softening, while frozen silt showed strain-hardening. Subsequent investigation considered the influence of fines content on the unconfined compression behavior of frozen soil mixtures with fines contents of 0-100%. The mixtures showed a brittle-to-ductile transition of failure patterns at 10%-20% fines content.

• 한국축산식품학회지
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• 제34권6호
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• pp.757-762
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• 2014

The object of this study was to investigate the difference in physical and sensory properties of various premium ice creams. The physical properties of the various ice creams were compared by manufacturing brand. The water contents of the samples differed, with BR having the highest value at 60.5%, followed by NT and CS at 57.8% and 56.9%, respectively. The higher the water content, the lower Brix and milk fat contents in all samples. The density of the samples showed almost similar values in all samples (p>0.05). The viscosity of each ice cream had no effect on the water content in any of the brands. Before melting of the ice cream, the total color difference was dependent on the lightness, especially in the vanilla ice cream, owing to the reflection of light on the surface of the ice crystals. The CS product melted the fastest. In the sensory test, CS obtained a significantly higher sweetness intensity score but a lower score for color intensity, probably due to the smaller difference in total color, by which consumers might consider the color of CS as less intense. From this study, the cold chain system for ice cream distribution might be important to decide the physical properties although the concentration of milk fat is key factor in premium ice cream.

• 한국농공학회지
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• 제33권2호
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• pp.112-119
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• 1991

Some experiments were carried out to investigate the effects of freezing and thawing on the strength and strain characteristics of alluvial silty clay under the different temperatures, loading and moisture conditions. The results were as follows; 1. The soil used was proved to be consisted of silty clay with honey-combed structure, and showed higher dilatancy, frost activity and lower stability in natural state. 2. Soil treated with freezing and thawing cycles showed lower compressive strength compared with the non treated, The strength decreased with incement of freezing and thawing cycles. It's shapes of stress-strain curves were flat and did not formulate a peak while the peak strength of higher moisture content soil decreased with the increment of moisture content. It's decrement ratio was most distinctly shown at the first one cycle of freezing and thawing. 3. The cohesion decreased due to freezing and thawing cycles but internal frcition angle was not changed. 4. The liquid limit decreased with increment of freezing and thawing cycles, and became almost constant after three cycles of freezing and thawing. 5. The strength under simple loading at failure mode was appeared to be higher compared with the cyclic loading after freezing and thawing but initial moisture content effect was not observed. 6. Ice lense was not observed within 50% of ice content ratio but observed over 100%. The higher the ice content ratio, the higher the peak strength. As a matter of fact, it seems that an optimum ice content ratio exists for plastic mode and the least compressive strength.

• 한국생활과학회지
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• 제21권2호
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• pp.377-388
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• 2012

The purpose of this study was to determine the content attributes and sensory characteristics of ice cream flavored with lotus leaf and seeds (Nelumbo nucifera Gaertner). Analysis of freeze dried lotus leaf powder produced the following technical results: Freeze dried lotus leaf powder contained moisture 12.2, crude protein 5.9, crude fat 1.2, crude ash 7.0, crude fiber 13.4g/100mg; raw lotus seed powder contained moisture 65.0, crude protein 8.2, crude fat 0.3, crude ash 1.0, crude fiber 10.8g/100mg; freeze dried lotus seed powder contained moisture 14.0, crude protein 17.1, crude fat 1.9, crude ash 4.0, crude fiber 2.8g/100mg. Lotus seed was processed by 4 methods: freeze dried, roasted, freeze dried peeled inner layer, cooked cut peeled inner layer. Analysis of the color value produced the following technical results: freeze dried lotus leaf powder were L(lightness) 14.5, a(redness) 4.4, b(yellowness) 24.0; freeze dried lotus seed powder L 57.3, a 14.4, b 12.0; roasted lotus seed powder L 52.7, a 22.5, b 11.9; freeze dried lotus seed peeled inner layer L 60.0, a 1.4, b 12.3. Proportional lotus ingredients used for ice cream were 1%, 3%, 5%, 7%, 10% for lotus leaves and 1%, 3%, 5% for lotus seeds. The maximum over run ratio for lotus leaf ice cream was 45.3~56.9% at 20~25 minutes operating time. Over run was significantly decreased by increasing the contents of lotus leaf powder. A maximum over run ratio for lotus seed ice cream was 46.1~54.3% at 20~25 operating time. Over run was not significantly different based on content of lotus leaf versus lotus seed. Sensory evaluation of lotus leaf ice cream produced the following results: the highest score was for color of 4.42 and the lowest score was for sweetness of 3.30. The total mean score significantly decreased by increasing the content of lotus leaf powder. Sensory evaluation of lotus seed ice cream produced the following results: the highest score was for cooked cut peeled inner layer type and the lowest was for freeze dried type 3.86. The sensory scores were not significantly different based on the content of lotus seed. Texture was evaluated highest with a rating of 4.21 and the taste was evaluated lowest with a rating of 3.68 For whole evaluation. This study concluded that lotus leaf ice cream demonstrates relative strength in terms of color and taste, and a relative weakness in terms of over run and sweetness. Suitable content of lotus leaf ranged from 1~5%. The lotus seed processed by the cooked cut peeled inner layer method received a higher rating than dried powder for lotus seed ice cream.

• 한국잠사곤충학회지
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• 제45권2호
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• pp.85-89
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• 2003

최근 건강기능식품에 대한 소비자들의 선호도가 증가함에 따라 안전성, 기능성, 안정성을 지닌 천연물에 대한 관심이 높아지고 있으나, 아이스크림은 기호성이 큰 식품이기 때문에 기능성이 가미된 아이스크림을 제조하기가 쉽지 않다. 이에 건강기능식품의 조건을 만족시키는 기능성식품 소재로서 뽕나무 오디를 첨가하여 기호성과 기능성을 공유한 기능성 아이스크림을 제조하였으며, 관능평가 및 영양성분 분석을 실시하였다. 그 결과를 요약하면 다음과 같다. 1.오디 샤베트 아이스크림과 아이스 바 모두 2％ 첨가구의 선호도가 높았으며, 제품의 기호도를 결정짓는 인자는 '색상'과 '맛'이었다. 2. 일반성분 분석결과 오디 농축물 첨가비율이 증가할수록 오디 샤베트 아이스크림과 아이스 바의 조단백질, 조회분 함량이 무처리군에 비해 유의하게(p＜0.05)증가하였으며 조지방은 오디 농축물 첨가율에 따라 증가하는 경향이 있었으나 유의적인 차이는 나타나지 않았다. 3. 무기질 함량은 오디 농축물의 첨가율이 증가함에 따라 칼슘, 마그네슘, 칼륨, 나트륨, 철분 및 아연 함량이 증가하는 경향이었으며 다른 무기질에 비해 칼슘과 칼륨함량이 높은 것으로 나타났다.

• 한국응용과학기술학회지
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• 제37권4호
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• pp.860-869
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• 2020

본 연구는 근해에서 잡은 고등어의 신선도유지효과를 확인하기 위해 해수 슬러리얼음(SS), 해수 큐브얼음(SC), 수돗물 슬러리얼음(TS), 수돗물 큐브얼음(TC)에 저장하며, 신선도분석을 시행하였다. 각 얼음 성분 중 세균수는 음용수 기준 이하였고, 암모니아성 질소는 해수 기준치인 11 mg/L를 초과했다. 민물에 비해 바닷물의 탁도가 심했다. 고등어의 일반성분 분석결과 수분 함량이 72.7%, 단백질 20.5%, 지질 5.25%, 회분 함량이 1.3%로 나타났다. 해수 슬러리 얼음은 수돗물 얼음과 비교하여 pH가 낮게 유지되었다. 저장 초기에는 모든 저장소에서 VBN 증가가 억제되었다. 전반적으로 해수빙이 담수 얼음보다 휘발성 염기질소(VBN) 값이 낮게 유지 되었다.

• 한국지반공학회논문집
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• 제39권6호
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• pp.13-19
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• 2023

달 얼음은 향후 인류의 심우주 탐사와 장기 체류를 위한 자원으로 활용될 수 있다. 달 얼음에 대한 기원 및 존재 유형은 여전히 가설로 남아 있다. 최근 세계 우주국에서는 달 얼음에 대한 원격탐사에서 지상탐사를 통해 정량적 매장량과 존재 유형을 밝히고자 경쟁적으로 미션을 계획하여 추진 중에 있다. 달 얼음의 매장량이 충분하다면 향후 얼음을 자원으로 활용하는 현지자원활용 개념이 각광받을 것으로 예상된다. 그러나 현재까지 얼음 추출에 따른 지반 공학적 관점에서 유의해야 하는 침하에 대한 검토는 전무한 실정이다. 본 연구에서는 인공월면토-얼음 존재 유형별로 얼음 추출로 인해 발생 가능한 침하량에 대한 실험적 연구결과를 제시하고 있다. 그 결과 초기 함수비 약 10%의 인공월면토-얼음 혼합토에서 상당한 침하가 발생하였다.

• 한국식품과학회지
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• 제46권2호
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• pp.173-179
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• 2014

국내산 포도주의 품질 개선을 위한 발효 방법으로 국내산 포도 Muscat Bailey A를 동결건조기를 이용하여 인공적으로 당분을 농축시키고 이를 발효하여 아이스와인을 제조하였으며 시중 아이스와인과 같이 환원당이 많이 잔존하면서 알코올 도수는 $10{\pm}5%$ 내외로 발효를 종료해 일반적으로 제조한 포도주와 비교하여 품질 특성을 조사하였다. 일반적 아이스와인 기준과 유사한 포도즙(must) 당도 $34.8^{\circ}Bx$와, 보당에 따른 포도주 발효에서 정상 발효될 수 있는 한계점으로 생각된 포도즙 당도 $40.8^{\circ}Bx$로 포도를 동결건조한 후 포도주를 제조하였으며, 포도주 발효 과정 중에 발효특성을 알코올, 당도, 환원당 함량과 pH, 총산, 효모생균수, 포도주 생산량을 측정해 보았는데, ice wine $34^{\circ}Bx$와 ice wine $40^{\circ}Bx$는 농축된 당, 산으로 인해 발효가 종료되었을 때 잔존하는 환원당은 대조구가 0.3%인 반면 ice wine $34^{\circ}Bx$와 ice wine $40^{\circ}Bx$는 각각 21.5%와 23.9%를 나타내었다. 또한 알코올 함량은 대조구 9.6%에 비해 각각 10.3%와 10.6%를 나타냈으며, 총산 함량이 높았고 정상발효가 일어났음을 확인할 수 있었다. 유리당, 유기산 조성을 보아도 아이스와인의 경우가 발효전후에 함량이 높게 나왔으며, 총 페놀함량도 468 mg/L인 대조구와 비교하여 ice wine $34^{\circ}Bx$와 ice wine $40^{\circ}Bx$는 각각 1,304, 1,350 mg/L로 높아 건강기능적인 측면에서도 우수함을 알 수 있었다. 메탄올, 알데히드함량은 식품공전의 기준치를 넘지 않았으며, 농축되어 진한 색을 띈 ice wine $34^{\circ}Bx$와 ice wine $40^{\circ}Bx$는 520 nm 흡광도에서 높았으며, 이는 색도 L, a, b 값을 통해서도 확인하였다. 시중 판매되는 레드 아이스와인인 Pinot Noir ice wine과 sweet wine인 Concord 품종 와인을 포함하여 5가지 포도주의 색, 향, 단맛, 종합적 기호도를 조사한 결과 환원당이 가장 높은 Pinot Noir ice wine이 단맛에서 강도가 가장 높았고, ice wine $34^{\circ}Bx$와 ice wine $40^{\circ}Bx$가 색, 향, 종합적 기호도에서 우수함을 알 수 있었다. 전체적인 기호도에서는 색, 향이 우수하면서도 적당한 단맛을 가진 ice wine $34^{\circ}Bx$가 가장 우수한 기호도를 보였다.

• International Journal of Knowledge Content Development & Technology
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• 제9권4호
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• pp.31-45
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• 2019

In this study, a database was established by analyzing the record data research produced in ice hockey sports. The deployed data verification with Ice hockey reference service was demonstrated with ice hockey officials and players. This research utilized the data stored in the KNSU Datanest data repository and developed PDF parsers for batch processing of records. Among the types of records, the game summary, team roster, team statistics, and player statistics files were collected, and tables were extracted from the records. PDF records were converted to text in CSV format which are converted to DataFrame and loaded into the database. Out of the total 22 types of records, 4 types were constructed with OO data parsed as element values. Data verification has found no problems with the quality of the data deployed, showing a high satisfaction with providing 66 factors against the 30 factors provided by the service previously used.

• 설비공학논문집
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• 제21권9호
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• pp.496-504
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• 2009

In order to investigate the feasibility of a direct ice slurry transporting system for the purpose of district cooling, a case study of field application is performed. The research aims include the field measurement of ice packing factor, the performance of coldness delivery, and the branching characteristics of ice slurry. Two representative types of pipe branch are dealt with in this work. For the slurry flow with ice volume fraction of 0.16 or less, the pipe blocking due to aggregation is not observed. Based on the time-wise variation of temperature in the storage tank, a calculating method of ice packing factor is newly developed, which seems to be useful when the brine concentration is unknown. It is confirmed that the mass flow rate of ice slurry per unit cooling load is markedly reduced with increasing the ice content. The pumping power also decreases, but remains unchanged for high ice fractions. The distribution of ice particle before and after branching shows a good uniformity within the range of 5% difference, but yields a unique trend depending on the flow rate.