• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.11-16
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• 1984

Rheological properties of waxy and non-waxy rice starch solutions were evaluated with a narrow gap rotational and Cannon Fenske viscometers. The gelatinized rice starch solutions containing 0.2-1.0% starch displayed pseudoplastic flow behavior. At higher starch level, degree of pseudoplasticity of waxy rice starch solutions increased, while that of non-waxy rice did not changed apparently. The consistency coefficient (K) of non-waxy rice starch solutions increased with increasing gelatinization temperature, but waxy rice starch solutions remained constant, and in alkaline aqueous solutions both of them showed increasing K values. The value of K increased exponentially with an increase in concentration. The effect of the temperature on the viscosity of the solutions followed Arrhenius' type equation, and the activation energies were in the range of 3.675-3.775 kcal/g-mol that were near to that of pure water. The changes of reduced viscosity with concentration were followed Huggin's equation and the values of intrinsic viscosity and interaction coefficient were 0.78-1.59 dl/g and 0.67-2.75, respectively.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.637-643
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• 2007

In this report, we discussed the physiochemical characteristics of corn starch during the alkali gelatinization process. Here, solubility and the amounts of eluted polysaccharides and amyloses increased in proportion to the amount of alkali added. The X-ray diffraction patterns and DSC thermogram showed that in the early stage of alkali gelatinization, crystallinity of the starch granules was disrupted as compared with heat gelatinization. This resulted in the eluted amylose content, while granule sizes were hardly changed in the alkali treated corn starch. The endotherm peak in the DSC thermogram shifted toward a higher temperature region as the degree of gelatinization increased, suggesting that the retained starch granules were more compactly crystallized during alkali gelatinization than during the heat process. Thus, we concluded that during the alkali gelatinization of corn starch, the disruption of weak particles would occur first, before swelling of the granules.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.88-98
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• 1978

Amylose content, water absorption and amylograph characteristics of waxy and nonwaxy barley varieties were studied. Amylose content of nonwaxy varieties ranged from 23.4% to 31. 5% and waxy varieties showed 5.4%-9.5%. Water absorption of waxy varieties was highest among the materials tested. Waxy barley showed lowest gelatinization temperature among the varieties. Gelatinization temperature was positively related with the maximum viscosity in all tested varieties. There was no relationships between amylose content and gelatinization temperature, gelatinization time and viscosity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.428-435
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• 1992

Intrinsic viscosity and gelatinization properties of brown rice starches of Japonica and Tonsil type cultivars were investigated. The intrinsic viscosity was similar between the two cultivars. The gelatinization temperature of Japonica brown rice starch determined by differential scanning calorimetry was higher than that of Tonsil brown rice starch. However, the range of gelatinization temperature, gelatinization enthalpy and the water content for gelatinization were similar between the two starches. The treatment of starch at 6$0^{\circ}C$ for 24hr increased the gelatinization temperature and gelatinization enthalpy and decreased the range of geltinization temperature. The water content for gelatinization was negatively correlated with the range of gelatinization temperature in case of Japonica starch and with the intrinsic viscosity in case of Tonsil one. The in-trinsic viscosities of both Japonica and Tonsil starches were positively correlated with gelatinization enthalpy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.181-185
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• 1993

The effects of concentrations (6~9%), heating temperatures (80, 85, 90 and 95$^{\circ}C$) and heating methods (continuous, method A and instantaneous, method B) on the flow properties of cowpea flour (air-dried sediment) at 6$0^{\circ}C$ were studied. The gelatinized cowpea flour dispersions by method B had higher values of yield stress and consistency index but lower value of flow behavior index compared to those values of method A. The log values of consistency index were positively correlated with the concentration and heating temperature for both methods. The rate of increase in the consistency index value by method B at the same concentration was greater in all heating temperatures than that by method A.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.366-370
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• 1987

Rheological properties of gelatinized rice starch solutions (5%) were examined with a Brookifield viscometer. Gelatinized rice starch solutions showed pseudoplastic flow having yield stress, i.e., Binghamplastic flow behavior. The yield stress of gelatinized rice starch solutions was reduced by the phosphate. Phosphate increased the pseudoplasticity of gelatinized nonwaxy rice starch solutions. but decreased that of gelatinized waxy rice starch solution. The yield stress of gelatinized nonwaxy rice starch solutions held for one hour at $90^{\circ}C$ was slightly decreased, but that of waxy starch solution was reduced by 10-fold. Phosphate reduced the yield stress for both gelatinized nonwaxy and waxy rice starch solutions. Phosphate decreased the consistency index, but did not affect the flow behavior index of the gelatinized rice starch solutions.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.05a
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• pp.192-193
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• 2019

클라우드 스토리지는 다양한 영역에서 이용가능하다. 일반적으로 데이터 저장, 이용에 사용되지만 추가적으로 데이터의 공유에 이용될 수도 있다. 이를 활용하여 단순 데이터 공유 및 데이터 구독 서비스 등 다양한 영역에 이용될 수 있다. 프록시 재암호화는 이러한 환경에서 데이터를 제 3자에게 안전하게 전달하기 위해 제안되었다. 프록시 재암호화는 데이터 소유자가 데이터를 암호화 한 뒤, 프록시에 보관하고, 위임자의 요청에 따라 데이터 소유자가 재암호화 키를 생성하여 프록시가 암호화된 데이터를 재차 암호화 할 수 있도록 한다. 프록시 재암호화는 암호화된 데이터를 제 3자에게 전달하기 위해 복호화 할 필요가 없기 때문에 데이터 원본을 노출 없이 안전하게 전달할 수 있다. 하지만 이러한 과정에서 프록시와 위임자가 결탁하여 데이터 소유자의 개인키를 복구하거나 재암호화 키를 위조하는 등의 위협이 발생할 수 있다. 이를 공모(결탁)공격이라 한다. 본 연구에서는 프록시 재암호화 기술에서 발생할 수 있는 공모공격을 방지하여, 보다 안전하게 이용할 수 있는 방법을 제시한다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1467-1475
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• 2016

To make soft and less stale bread, various amounts of gelatinized wheat flour dough were added for making pan bread. In the dough process, higher gelatinized wheat flour dough showed higher consistency and dough development time but a lower dough stability time. Expansion during fermentation represented the highest value upon addition of 10% gelatinized wheat flour dough (GWFD), and this value decreased with increasing amount of gelatinized wheat flour dough. Volume of bread was the highest in the control and lowest in 30% GWFD, and there was no difference between 10% GWFD and 20% GWFD. Moisture contents of bread made with various amounts of gelatinized wheat flour dough increased with increasing gelatinized wheat flour dough amount. Color values of bread made with various gelatinized wheat flour dough were not significantly different. Chewiness, brittleness, and hardness of bread made with control and 10% GWFD showed low values, whereas bread made with 20% GWFD and 30% GWFD showed high values. During storage, chewiness, brittleness, and hardness increased with increasing storage period in whole breads, whereas breads made with 10% GWFD showed the lowest increasing rate. In the sensory strength test, chewy texture increased upon addition of gelatinized wheat flour dough. In the consumer acceptance test, 10% GWFD showed the most overall acceptance. In conclusion, bread made with 10% gelatinized wheat flour dough is desirable for increasing softness and decreasing bread staling.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1277-1282
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• 2013

The effects of pregelatinized rice flour (PRF) as an additive on the textural properties of rice cookies were investigated in this study. PRF was used at 10, 20, 30, 40, 50, and 60% per 100 g of rice flour. The hardness of dough and cookies, as measured by a texture analyzer, increased upon the addition of PRF. In contrast, the moisture content of the dough and cookies decreased upon the addition of PRF. The L value of the dough and cookies decreased upon the addition of PRF, whereas the a value increased upon the addition of PRF. The bulk density of the cookies increased upon the addition of PRF. In addition, the spreadability of the cookies was lower than the control. In the sensory evaluation, rice cookies with 50% PRF showed the highest scores for hardness, brittleness, softness, and moisture. Rice cookies with 60% PRF showed the highest scores for sandiness. Our results suggest that the texture of the rice cookies can be improved by adding PRF.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.2
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• pp.147-155
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• 2013

Proxy re-encryption scheme has advantage where plaintext does not get exposed during re-encryption process. This scheme is popular for sharing server-saved data in case of cloud computing or mobile office that uses server to save data. Since previous proxy re-encryption schemes can use re-encryption key over and over again, it may abuse re-encryption. To solve this problem, conditional proxy re-encryption scheme was proposed. But, it is computationally expensive generate the same number of re-encryption key with the number of condition values. In this paper, we propose an efficient conditional proxy re-encryption scheme in terms of re-encryption key generation. The proposed scheme uses only encryption and decryption process. Therefore it has advantage to generate one re-encryption key for one person. The proposed scheme is secure against chosen-ciphertext attack.