• Korean Journal of Plant Resources
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• v.35 no.4
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• pp.455-463
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• 2022

The effects of freeze-drying (FD), room-temperature drying (RD), and room-temperature drying after roasting (RDAR) on the volatile organic compounds (VOCs), sugar content, flavonoids, and antioxidant activity of Hallabong peel tea were tested. This experiment was conducted to collect a basic information for developing of peel tea. FD samples showed lower total soluble solids and VOCs than other drying treatments. RDAR samples showed a significant difference in VOCs and visual color of FD samples. The reduced VOCs in FD samples was caused by freeze drying treatment; identical VOCs composition of hallabong peel was detected from condensed ice of freeze-drying machine. Metabolomics analysis showed no difference among three drying treatments. In addition, antioxidant activity and total phenolic compounds were not significantly different from three different drying treatments. Thus, RD or RDAR is a suitable drying method for hallabong peel tea rather than FD method in terms of VOCs and economical reasons.

• Journal of Ocean Engineering and Technology
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• v.16 no.1
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• pp.71-75
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• 2002

대형 시추구조물의 건조는 보통 드라이도크에서 하거나, 해양에서 선체와 데크를 접합하는 방법을 사용한다. 그러나 적당한 해양 접합장소가 없거나 드라이도크의 공간부족으로 현대중공업에서는 드라이도크나 해양에서의 접합건조 대신 부유식 시추구조물을 지상에서 조립하는 방법을 채택하게 되었다. 현대중공업에서는 세 가지 단계를 통해 지상 데크조립을 수행하였다. 첫 번째는 네 개의 철골구조 리프팅타워 상에서 유압리프팅시스템을 이용하여 데크를 지상으로부터 38m 들어올린다. 두 번째는 마찰을 줄이기 위해 윤활제가 칠해진 합성 플라스틱으로 싸인 미끄럼틀(Skidway)을 이용하여 두 개의 6000톤 짜리 하부구조를 데크 아래로 끌어 들인다. 마지막 단계로 데크와 하부구조를 단단히 결합시킨다. 이 과정에 2주일이 소요되었으며 일련의 작업을 거쳐 중량 25,500톤급의 Deepwater Nautilus (RBS-8M) 시추선을 무사히 바다 위로 인도하였다. RBS-8M의 데크결합에 Super Lift를 적용하여 성공시킨 사례를 통해 현대중공업의 초대형 시추구조물 건조방식이 이상적이고, 작업 공기나 원가 측면에서 우위가 있음을 시사하고 있으며 이렇게 건조작업의 대부분을 지상에서 수행한 과정을 통해 작업관리, 품질관리, 일정관리에도 좋은 결과를 가져올 수 있었다.

• Food Science and Preservation
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• v.14 no.1
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• pp.61-66
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• 2007

This study investigated changes in physicochemical properties of onion powders during various drying conditions. The moisture content during vacuum drying at $40^{\circ}C$ remained at 5.23% for 5 days of drying, and it was possible to quickly obtain day powder Weight reduction upon $-70^{\circ}C$ vacuum drying was 90% after 7 days. The large change in browning caused by vacuum freeze drying was lowest ($OD_{420}\;of\;1.173$) after 7 days of drying. The content of vitamin C increased with vacuum freeze drying. The major free sugars were fructose, glucose and sucrose. Of organic acids, citric acid was prominent and, after vacuum freeze drying, showed a high value of 1,965 mg/100g. Free amino acids noted were L-arginine, ${\beta}-alanine$, L-alanine and L-threonine. In summary, vacuum freeze drying at $-70^{\circ}C$ is optimal.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.613-619
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• 2013

Konjac gel is known as a low calorie food, because the main component is water. Mugwort has been used for food and medicine for a long time due to itsfunctional property, which contains a lot of vitamins and minerals. Therefore, konjac noodle-added mugwort was prepared. The konjac gel was made by from a centrifuge after adding water, alkali and mugwort power in konjac flour. The centrifuge was used to remove air in the gel. After centrifuging by heating the gel in boiling water for one hour, konjac noodle was made by pressing using a flat heating press. The results are as follows. In the drying process of mugwort freeze drying after blanching in 1% $NaHCO_3$ solution is better than other drying methods. The physical properties (hardness, elasticity, cohesiveness, gumminess) of konjac gel were measured with a Rheometer. The optimum processing conditions were decided by these measured values. The optimum condition of making konjac gel is 9% concentration of konjac flour, a ph of 12.0, $Na_3PO_4$ coagulant and 1.5% concentration of mugwort power in konjac flour.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.250-255
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• 2004

To analyze delay, Seoul - Daegu line of Korea High Speed Railway was divided into three sections and analyzed independently by the business characteristics. The analysis on the project delay reasons was performed on macro and micro scales. This analytic method was named as 'Macro-Micro Delay Analysis Method (MMDAM)'. The macro scale analysis has three approaches, which are (1) scheduling, (3) structural characteristic, (3) and responsibility of project administrative works. Micro analysis also has three, methodologies which are (1) As Planned Method, (2) As Built method, (3) Modified Time Impact Analysis for analyzing the most influential section which the largest delay occurred. Using elicited project delay reasons from above analysis, the questionnaire was carried out for analyzing the influence of project delay reason. The reasons of the delay were driven from two different aspects (1) structural characteristic and (2) responsibility of the people involved in the project. The reasons that were identified from aforementioned three sections are the factors of the delay of the large-scale government driven projects. Finally, the author suggested the methodology of identifying the project delaying factors. The author also analyzed delay reasons in both the overseas and domestic cases of high rapid railway construction and has elicited some benchmarks for the future projects.

• Food Science and Preservation
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• v.11 no.2
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• pp.269-275
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• 2004

This study was conducted to develop an optimization model using Box's Complex Algorithm, and to determine optimum operating conditions to minimize costs for the drying and storage system using the grain cooler. To minimize the system operation cost, the optimum moisture contents after the first drying were found to be from 17.2 to 19.8 %. And optimum drying and cooling capacities were obtained. The combination of the dryer and grain cooler was found to be economical, showing enhancement of the drying capacity over 50%, and decrease of drying cost over 10%. When the circulating grain dryers of 6 and 20 ton/batch were used in conjunction with the grain cooler, the cost required for drying and storage system for paddy were 28,464∼33,317won/ton and 20,588∼26,511 won/ton, respectively, which was from 2.6 to 27.3% lower than that of conventional drying and storage system.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.716-721
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• 2012

This study was designed to compare the quality characteristics of spray-dried (SD) and freeze-dried (FD) powders prepared with hot water extracts of sea mustard (Undraia pinnatifada) and sea tangle (Laminaria longissima). The moisture content of FD seawed was lower than that of SD, and sea mustard had a higher overall moisture content than sea tangle. The alginic acid content of SD seaweed was significantly higher than that of FD seaweed for both species. There were relatively higher contents of phenolic compounds in SD powders than in FD powders. DPPH radical scavenging ability was significantly greater in SD seaweed, and also, SOD-like activity in SD powders was higher than those of FD powders. However, the nitrite scavenging activity of FD powders of sea mustard (10 mg/mL) was higher than that of SD. In conclusion, spray-dried sea mustard and sea tangle extracts exhibited higher physiological functionalities than their freeze-dried counterparts.

• Journal of agriculture & life science
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• v.43 no.6
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• pp.111-115
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• 2009

This study was conducted to develop the ultrasonic dryer because present drying methods (heat convection, microwave, vacuum, etc.) could not improve the drying consumption energy, decrease of quality and drying ratio by physical limitation. The drying tests were conducted with four levels (No. 1 only non-heated air, No. 2 only ultrasonic, No. 3 only heated air and No. 4 ultrasonic with heated air) and measuring weight of samples after drying carrot and ginseng slices for 30 minutes. The result of test is that the drying ratio was highest in the level of No. 4 ultrasonic with heated air. The sliced carrot's drying ratio was 22.4% (w.b.)/h and sliced ginseng's drying ratio was 3.8% (w.b.)/h. The discoloration and twist of samples was appeared on using only heated air like No. 3.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.416-423
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• 1993

Milk powders were made by several drying methods and raw materials, and rheological properties of milk powders were investigated by an Instron Universial Testing Machine. The results obtained are summarised as follows. Bulk density of the drum dried whole milk powder was $0.382\;g/cm^3$ and was higher than that of other milk powders. The Hausner ratio, angle of repose and compressibility of the spray dried skim milk powder were 1.127, $32.5^{\circ}$ and 0.029 respectively. This result indicated that skim milk powder showed free flowing characterristics. The compressibility of the drum dried whole milk powder was decreased by the decrease of moisture content. Compressibility of the milk granule was 0.056 and was lower than that of milk powder. The spray dried milk powder of a grobular shape had higher solidity than the freeze or drum dried milk powder. The drum dried milk powder particles consist of irregular shape.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.25-30
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• 1989

Effects of cooking and drying methods on the composition of glycolipids and phospholipids of shrimp, Metapenaeus joyneri, were investigated. Major components of the glycolipids were esterified steryl glycosides, monogalactosyl diglycerides and steryl glycosides. Hot air drying enhanced the esterified steryl glycosides content substantially with the reduction of the monogalactosyl diglycerides content. However, reversed pattern was shown for freeze drying. Main components of the phospholipids were phosphatidyl ethanolamines, phosphatidyl cholines, phosphatidic acids, phosphatidyl inositols and phosphatidyl serines. Phosphatidic acids content for hot air and freeze dried shrimp without tooting was 8.3% and 5.9%, respectively. On the other hand, freeze dried shrimp with microwave heating was higher in phosphatidyl ethanolamines contents but lower in phosphatidyl cholines contents than hot air dried shrimp. Major fatty acids of the glycolipids and phospholipids fractions were pentadecanoic acid, palmitic acid, oleic acid, nervonic acid and eicosapentaenoic acid in fresh shrimp.