• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.554-554
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• 2000

To improve mechanical properties of Cu-Al-Ni alloy by the grain refinement, Cu-Al-Ni SMA ribbons were fabricated by melt spinning apparatus. The variations of microstructure, mechanical properties and transformation characteristics with the condition of rapid solidification and annealing time-temperature were investigated in Cu-Al-Ni SMA ribbons. The ribbons fabricated by melt spinning obtained around 1.5nm in width and 50-60${\mu}{\textrm}{m}$ in thickness. With increasing wheel speed in order of 10m/s, 15m/s, 20m/s, 30m/s and 3m/s, the grain size was decreased in order of 10${\mu}{\textrm}{m}$, 6.25${\mu}{\textrm}{m}$, 5.5${\mu}{\textrm}{m}$, 3${\mu}{\textrm}{m}$ and 3${\mu}{\textrm}{m}$. $M_{s}$ and $A_{s}$ temperature were decreased with decreasing grain size. By X-ray diffraction test, ordered $\beta$$_1$ phase was observed in all the SMA ribbons and the volume friction of it was increased with increasing wheel speed. With increasing wheel speed, strain was increased from 4.2% to 5.8% and fracture mode has changed from mixture of intergranular and dimple fracture to mixture of fiber structure and dimple fracture. The grain size of ribbon heat-treated at $600^{\circ}C$ was increased with increasing time. In the heat-treated ribbons at 55$0^{\circ}C$, ${\gamma}$$_2$ phases were observed.d.d.

• 동력기계공학회지
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• 제16권4호
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• pp.60-65
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• 2012

This study was carried out to investigate the effect of reverse transformation on the damping capacity in high manganese austenitic stainless steel. ${\alpha}^{\prime}$-martensite was formed with the specific direction and surface relief by deformation. Over 95% of the austenite phase was transformed to deformation-induced ${\alpha}^{\prime}$-martensite by 70% cold rolling. Reverse transformation became rapid above an annealing temperature of $550^{\circ}C$, but there was no significant transformation above $700^{\circ}C$. In addition, with increasing annealing time at $700^{\circ}C$, reverse transformation was induced rapidly, but the transformation was almost completed at 10 min. Damping capacity was increased up to $700^{\circ}C$, and than unchanged with the increasing annealing temperature. Damping capacity increased steeply with an increasing reverse treatment time up to 10min, whereas there were no significant change with a treatment time of more than 10 min. Damping capacity increased with an increasing the reversed austenite and was strongly affected by reversed austenite.

• 보건행정학회지
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• 제19권1호
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• pp.62-80
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• 2009

The purpose of this study was to examine the factors influencing the attitude toward the increasing role of private health insurance(PHI). In the Korea Welfare Panel Data 2007, a sample of 1,675 (adjusted by weight value: 1,607) respondents on an opinion on promoting PHI was used in the study. With independent variables including socio-demographic characteristics, health status, health-related behavior, and opinions on welfare service, ordered-probit model was used to analyze the attitude toward PHI. Negative opinion on the increasing role of PHI were responded by 54.6%(n=877) of the respondents, whereas 22.2%(n=373) were positive and 23.2%(n=357) were neutral. Old people, the better off, those with worse self-assessed health status, and those having an experience of health examination tend to have the positive attitude toward the increasing role of PHI. Women, those with chronic diseases or disorders and those who do not agree that comprehensive welfare benefits reduce work incentive showed negative attitude toward PHI. When comparing the needs for PHI before and after medical utilization, ex-ante need tends to strengthen the tendency to support private health insurance. This study will contribute to the discussion on the optimal mix of public and private health insurance in Korea by a better recognition of attitude toward PHI and health care system.

• 한국식품영양학회지
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• 제12권5호
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• pp.484-489
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• 1999

Rosting conditions for improvement of viscosity and sensory properties of sea tangle extracts were investigated. The supernatant % solid yield and crude protein yield were increased by increasing of roasting temperature and times. The highest contents of algin was obtained in roasting temperature of 175$^{\circ}C$ ash contents were increased by roasting temperature increasing. Viscosities of sea tangle extract were significantly decreased by increasing of roasting temperature and time upto 175$^{\circ}C$ and 10 mins more than further roasting conditions. The pH of sea tangle extracts slightly decreased from 5.94 to 5.83 in the roasting of 15$0^{\circ}C$ however at temperature more than 175$^{\circ}C$ its pH was increased by increasing of temperature and time. According to increase of roasting temperature and time Lightness (L value) were significantly decreased and redness (a value) and yellowness (b value) reached the highest value in the roasting of 20$0^{\circ}C$ 15 min. or 175$^{\circ}C$ 30 min and after that its value were decreased. The odor characteristics showed that sea tangle extract prepared by roasting of 175$^{\circ}C$ 10mins was slightly reduced in intensity of savory and seaweed taste but significantly low in intensity of nauseous taste and high in intensity of roasted taste and accetability. Overall data suggested 175$^{\circ}C$ 10min was the most effective roasting conditions for improvement of viscosity and sensory properties of sea tangle extract.

• 한국식품영양학회지
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• 제33권2호
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• pp.183-193
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• 2020

The study was to investigate the quality characteristics of American waffles substituted with 0, 25, 50, 75, and 100% of kamut whole wheat flour (KWF). The KWF samples had maintaining the specific gravity of the batter until the 25% substitution. The spreadability decreased as the ratio of the KWF increased, and the pH of the 100% substitution sample were the lowest. The KWF samples had increasing baking loss rates until the 75% substitution while decreasing the water activity. Lightness and yellowness significantly decreased with increasing the KWF while redness increased. Hardness, chewiness, and gumminess of the 25% substitution sample were the highest, while the springiness and resilience were maximum with the 100% substitution. The KWF samples had increasing overall acceptability, acceptability of color, flavor, and texture until the 50% substitution. The characteristics intensity rating of crust color, bran flavor, and sweetness increased with increasing the KWF. The KWF samples had significantly higher crispiness than the control group. The frequency of the bran flavor, sweetness, nuttiness, and unpleasant increased while the egg and milk flavor, and flour taste decreased. These results suggest that the substitution of the 25~50% KWF could be the optimal to improve the quality characteristics of American waffles.

• 한국식품조리과학회지
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• 제28권6호
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• pp.665-673
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• 2012

The purpose of this study was to propose optimal mixing proportion by adding stevia in powder form, which are low caloric and high intensity sweetener to cookies, and to determine the characteristic of product. It reduced the average sugar content of cookies to 50%, processed stevia powder, add them in 2, 4, 6, and 8% to make cookies and measured various product characteristics, including anti-oxidant activity. The antioxidant activity was highly correlated with the total phenolic composition of stevia cookies (r=0.967). Total phenolic contents and DPPH free radical scavenging activity of cookies significantly increased with increasing stevia powder. The bulk density of the dough, spread factor and the hardness, total polyphenol contents and DPPH free radical scavenging activity of cookies significantly increased with increasing stevia powder, while the pH of the dough, and L values of the cookies decreased with increasing stevia powder content (p<0.001). Additionally, the consumer acceptability scores for the 4% stevia cookie groups ranked significantly (p<0.001) higher than those of the other groups in color, taste, flavor, sweetness and overall preference. All the take together, the results of this study suggest that stevia powder is a good ingredient for increasing the consumer acceptability and the functionality of cookies.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.55.2-55.2
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• 2011

This research aims to study the effects of the incidence angle and surface temperature on the power generation performance of a thin-film CIGS solar cell for solar powered unmanned aerial vehicles (UAVs). The test rig consists of a unit CIGS solar cell is installed on a table whose angle is controlled manually. A K-type thermocouple is attached to the solar cell surface for temperature measurements. A solar module analyzer measures the voltage and current generated from the test solar cell. The solar module analyzer also calculates the maximum solar power and efficiency of the solar cell. All test data are acquired in a PC. Test results show that the solar cell efficiency decreases significantly with increasing incidence angle and increasing surface temperature in general. As the incidence angle increases from 0 degree to 90 degree, the solar cell efficiency decreases by 60%. The solar cell efficiency decreases by 10% with increasing solar cell surface temperature from $20^{\circ}C$ to $30^{\circ}C$, for exmaple. The direct cooling method of the solar cell using dry ice decreases dramatically the solar cell surface temperature, thus increasing the solar cell efficiency by 15%.

• 열처리공학회지
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• 제13권4호
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• pp.265-271
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• 2000

The microstructural change and transformation characteristics with cooling rate i.e. wheel speed were investigated in 82.8wt%Cu-12.8wt%Al-4.3wt%Ni SMA ribbons fabricated by melt-spinning. The thickness and width of ribbon were decreased with increasing wheel speed, while the uniformity of it was improved. At same wheel speed, the grain size of the contact surface of ribbon was smaller than that of free surface. The mean grain size was decreased with increasing wheel speed, resulted in obtaining grains with $3{\mu}m$ in mean diameter in the wheel speed of 30 m/s. However, micro-voids and cracks at grain boundary could be observed at higher wheel speed. $M_s$ and $A_s$ temperatures were decreased, and $M_s{\sim}M_f$ and $A_s{\sim}A_f$ temperature ranges were broadened with increasing wheel speed. All the ribbons were retained the ordered $D0_3$ due to rapid cooling, the volume fraction of it was increased with increasing wheel speed.

• 열처리공학회지
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• 제10권3호
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• pp.209-217
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• 1997

Effect of Co content on the microstructure and damping capacity of Fe-23%Mn-X%Co alloy was studied. The volume fraction of ${\varepsilon}$ martensite of the alloy was increased with increasing Co content. The hardness was increased with lowering cooling temperature and increasing Co content in Fe-23%Mn-X%Co alloy, which is ascribed to the increase in ${\varepsilon}$ martensite content. The damping capacity of Fe-23%Mn-X%Co alloy was linearly increased with increasing the strain amplitude, and was constant regardless of Co content at the same volume fractions of ${\varepsilon}$ martensite when the low strain amplitudes ($1{\sim}3{\times}10^{-4}$) were applied, while the damping capacity with large strain amplitudes ($4{\sim}6{\times}10^{-4}$) became higher with increasing Co content at all valume fractions of ${\varepsilon}$.

• 한국의류학회지
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• 제23권8호
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• pp.1110-1118
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• 1999

This study was to examine the effects of garment types on thermal insulation using a thermal manikin. cotton polyester wool silk and rayon were selected as outer wears like a blouse a skirt slacks and one-piece for this study Acetate was chosen as a lining. Brief and upper innerwear with long sleeves(cotton) were also chosen as the innerwear. The results were as follows: 1. The thermal insulation of the garment of single layer was in proportion to the covering area of garment in all types of clothing. 2. On adding the innerwear or the lining or both the thermal insulation of the each garment of single layer were showed a different trends by garment types. The thermal manikin insulations of one-piece dress adding the innerwear was higher than those of blouse-skirt suits. The thermal insulation of one-piece dress adding the innerwear and lining was lower than those of blouse-skirt suits. 3. The increasing rates of thermal insulation of multi-layered garments had different value by garment types but garment made of rayon and silk were showed very high increasing rates of thermal insulation. 4. The increasing rates of the thermal insulation of one-piece dress added the lining the innerwear or both except polyester showed the highest value and then blouse-slacks suits' turn came ound Blouse-skirt suits had the lowest the increasing rates of thermal insualition value.