• Journal of the Korean Home Economics Association
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• v.39 no.1
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• pp.103-111
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• 2001

This study was attempted to investigate the effect of partial replacement of rice flour with black or brown rice flour on texture properties and retrogradation of Julpyun(Korean rice cake). In sensory evaluation, the Julpyuns replaced black or brown rice flour 20% had high score in color, flavor and overall acceptability not including mouthfeel. As the result of the measurement with texture analyzer, hardness, gumminess and chewiness of Julpyuns tended to decrease in proportion to the amount of black and brown rice flour in the formula. These resets implied that the degree of retrogradation of black and brown rice Julpyuns might be low. Julpyuns replaced with black rice were a little lower than those of brown rice in the hardness. In the retrogradation speed by Avrami,s equation, the rate constants of Julpyun replaced black and brown rice flour was lower than that of milled rice, restating in delay in firming.

• The tire
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• s.67
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• pp.3-10
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• 1976

• International Journal of Highway Engineering
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• v.4 no.4 s.14
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• pp.53-66
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• 2002

Asphalt binder characteristics in asphalt mixture are changed due to aging. However. depending upon aggregate and binder used, asphalt mixture dose not show the same level of stiffness and brittleness under the same ageing level. The factors affecting Physical Properties change of the asphalt binder within aged asphalt concrete are not well known and there is limited study which is dealing with this topic This study dealt with evaluation of physical properties of asphalt binder recovered from the mixtures after short-term and long-term aging. Two asphalts. two aggregates. two gradations and four polymers were used to make 32 mixture combinations. The mixtures were prepared and aged artificially in a forced draft oven. The measured physical properties included absolute viscosity, kinematic viscosity and penetration. Statistical analyses were carried out to find out the factor(s) having a significant effect on change of physical property of asphalt binder due to asphalt mixture aging. The results of study shown that aggregate, gradation and polymer had a significant effect on change of physical properties of asphalt binder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.533-538
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• 2012

The retrogradation properties of a Korean rice cake ($Karedduk$) added with oligosaccharides after 0~30 hr of storage at $5^{\circ}C$ were examined by texture profile analysis and the Avrami equation using textural characteristics. Oligosaccharides, such as galactooligosaccharide (50%) and maltooligosaccharide, were added to dry rice flour at levels of 10%. In the amylogram, the breakdown (P-H) and consistency (C-H) of the Korean rice cake (Karedduk) added with oligosaccharides were lower than those of the control. Texture profile analysis using a Texture Analyzer revealed that the hardness of the Korean rice cake ($Karedduk$) added with oligosaccharides was lower than the control. The Avrami exponent ($n$) for the control, galactooligosaccharide (50%) 10% and maltooligosaccharide 10% addition was 2.415, 2.771 and 2.683, respectively. The time constant (1/$k$) for galactooligosaccharide (50%) 10% or maltooligosaccharide 10% addition was higher than the control. Overall, adding galactooligosaccharide (50%) 10% or maltooligosaccharide 10% to a Korean rice cake ($Karedduk$) is effective in retarding retrogradation.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.10
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• pp.21-26
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• 2003

In this research, the change of coefficient of thermal expansion (CTE) of graphite/epoxy composite laminate under space environment was measured using fiber optic sensors. Two fiber Bragg grating (FBG) sensors have been adopted for the simultaneous measurement of thermal strain and temperature. Low Earth Orbit (LEO) conditions with high vacuum, ultraviolet and thermal cycling environments were simulated in a thermal vacuum chamber. As a pre-test, a FBG temperature sensor was calibrated and a FBG strain sensor was verified through the comparison with the electric strain gauge (ESG) attached on an aluminun specimen at high and low temperature respectively. The change of the CTE in a composite laminate exposed to space environment was measured for intervals of aging cycles in real time. As a whole, there was no abrupt change of the CTE after 1000 aging cycles. After aging, however, the CTE decreased a Little all over the test temperature range. These changes are caused by outgassing, moisture desorption, matrix cracking etc.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.2
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• pp.43-51
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• 2020

After the accelerated aging, the bulkhead initiator using high explosives was carried out to verify aging characteristics. The Thru-Bulkhead Initiator operates by transmitting shock-wave generated from micro-initiator to the acceptor and the ignition explosives through the bulkhead. In order to evaluate the life-time of the product, the accelerated aging condition was set according to the life-time, and the ignition performance of the sample was measured every 10 cycles by measuring the delay time and the maximum pressure through the 10cc closed bomb test. In addition, variance analysis was used to determine aging.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.80-81
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• 1982

Staling rates of cooked rice from Akibare (Japonica) and Milyang 23 (Indica) stored at $21^{\circ}C$ and $72^{\circ}C$ were analyzed using the expression ${\theta}={\exp}\;(-kt^n)$, where ${\theta}$ in the fraction of uncrystallized material remaining after time t. The values for the rate constant (k) indicated that the firming process for both rices was not dependent on the variety, but was dependent on the storage temperature. The Avrami exponent (n) was found to be unity at two temperatures, suggesting that the staling of cooked rice is characterized by instantaneous nucleation followed by rod-like growth of starch crystals.

• Proceedings of the SCSK Conference
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• 1996.07a
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• pp.52-67
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• 1996

새로운 노화방지 물질로 개발한 3-APPA가 노화에 의해 야기되는 여러 변화들, 특히 세포 증식, 유전자 수준 및 단백질 수준에서의 collagen의 생합성 변화, 면역조직화학염색을 이용한 collagen 생합성의 변화등을 세포배양 및 동물실험을 통하여 측정하였다. MTT assay를 이용한 인체 피부 섬유아세포의 증식 실험에서 3-APPA는 무처치군에 비교해서 최고 2배의 섬유아세포 증식 효능을 나타내었으며, $^3$[H]-proline incorporation 방법을 이용한 단층세포 배양 및 3차원 dermal equivalent 섬유아세포 배양에서 무처치군 및 vitamin C 처리군에 비해 최고 1.5배의 collagen 생합성 증가를 나타내었다. 그러나 type I alpha-procollagen mRNA expression에는 영향을 미치지 않는 것으로 나타났다. H&E 염색을 이용한 hairless mice의 피부에 대한 형태학적 변화 및 type I pM procollagen antibody를 이용한 면역조직화학염색에서, 3-APPA는 collagen 생합성을 증가시키는 것으로 나타났다. 이상의 결과에서 3-APPA는 섬유아세포 배양 및 hairless mouse를 이용한 실험에서 피부 섬유아세포 증식을 촉진시키며 collagen 생합성을 증가시켜 피부노화를 억제 할 수 있는 물질임을 밝혔다.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.361-373
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• 2006

치주질환의 진행이 나이에 의해 영향을 받는다는 사실은 알려져 있으나 노화에 따른 치주조직 세포의 기능적인 변화에 관한 사실은 많이 알려져 있지 않다. 노화에 따른 세포의 노화가 치주질환의 진행에 어떠한 여향을 끼치는가를 아는 것은 중요하다. 염증 상태에서 nitric oxide (NO)는 조직 파괴에 관여하는 인자로 작용하여 치주질환의 진행에 관여하는 것으로 알려져 있다. 따라서 이 연구는 사람의 치은에서 배양된 치은섬유아세포를 이용하여 세포의 노화에 따른 NO와 이의 합성효소인 inducible nitric oxide synthase (iNOS)의 발현을 알아봄으로써 세포의 노화가 치주질환의 진행에 끼치는 영향에 대해 알아보고자 하였다. 10세의 환자와 55세의 환자에서 각각 채취한 치은에서 배양된 세포와 10세의 환자에서 채취한 세포를 계속적인 계대배양을 통해 얻은 실험실 상 노화된 세포를 포함하여 총 3 종류의 치은섬유세포를 실험에 이용하였다. Hot phenol-water extraction을 통해 추출된 Porphyromonas, gingivalis ATCC 33277 lipopolysaccharide (LPS)와 재조합 $IFN-{\gamma}$ 를 세포에 적용시켜 Griess assay를 통해 조건화된 배지에서 NO를 측정하였다. 20세와 55세의 환자에서 채취된 치은 조직과 총 3 종류의 배양된 세포에 NOS-II 항체를 적용시켜 iNOS 단백질 발현을 관찰하였다. Total RNA를 추출하여 RT-PCR를 통해 iNOS mRNA의 발현을 분석하였다. 치은섬유아세포에서 NO는 자발적으로 발생되었고, 이러한 발현은 젊은 세포보다 노화된 세포에서 강하였다. P, gingivalis LPS와 제조합 $IFN-{\gamma}$는 치은섬유아세포에서 NO의 발현을 증가시켰고, 이러한 발현은 젊은 세포보다 노화된 세포에서 강하였다. 면역조직화학 염색에서 iNOS 단백질은 젊은 사람과 노화된 사람의 치은 조직 모두에서 치은섬유아세포와 상피의 기저층 세포와 염증세포에서 발현되었으나 노화에 따른 발현의 차이를 구별할 수는 없었다. 세포의 면역염색에서 iNOS 단백질은 노화된 세포에서 강하게 발현되었고 이러한 발현은 LPS와 $IFN-{\gamma}$ 에 의해 강화되었다. LPS와 $INF-{\gamma}$ 의 조건이 주어지지 않은 상태에서 iNOS mRNA는 젊은 세포에서보다 노화된 세포에서 강하게 발현되었다. 이러한 결과를 통해 세포의 노화가 NO와 iNOS 발현을 증가시킴으로서 치주질환의 진행에 영향을 끼칠 수 있음을 시사하였다.

• 한국노년학
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• v.29 no.4
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• pp.1383-1396
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• 2009

In this study, we investigated the effects of perceived health and ageism experience of the elderly on successful aging, which were respectively presumed as predictors of biomedical model and psychosocial model of the successful aging. As important research results, firstly, negligence among ageism experience constructs appeared higher than other discriminatory experiences. Secondly, male showed significantly higher discriminatory experience than female in the area of 3 constructs such as property, negligence and employment ageism. Also there were some different discriminative experiences in the area of perceived health and ageism in terms of age, wealth and education. Finally, the results of hierarchical multiple regression hired to find out factors influencing successful aging showed that the factors such as sex, wealth, perceived health and property discrimination of ageism affected successful ageing. Based on the analytic results, we verified that perceived health, i.e., predictor of biomedical model had higher effect on successful aging than ageism experience, i.e., predictor of psychosocial model of successful aging. Thus, it was suggested that health promotion policy should be considered with priority and also combating ageism as well for successful aging.