BaTiO3-Poly vinylidene fluoride (PVDF) solution was prepared by adding 0~25 wt% BaTiO3 nanopowder and 10 wt% PVDF powder in solvent. BaTiO3-PVDF film was fabricated by spreading the solution on a glass with a doctor blade. The output performance increased with increasing BaTiO3 concentration. When the BaTiO3 concentration was 20 wt%, the output voltage and current were 4.98 V and 1.03 μA at an applied force of 100 N. However, they decreased when the over 20 wt% BaTiO3 powder was added, due to the aggregation of particles. To enhance the output performance, the generator was poled with an electric field of 150~250 kV/cm at 100 °C for 12 h. The output performance increased with increasing electric field. The output voltage and current were 7.87 V and 2.5 μA when poled with a 200 kV/cm electric field. This result seems likely to be caused by the c-axis alignment of the BaTiO3 after poling treatment. XRD patterns of the poled BaTiO3-PVDF films showed that the intensity of the (002) peak increased under high electric field. However, when the generator was poled with 250 kV/cm, the output performance of the generator degraded due to breakdown of the BaTiO3-PVDF film. When the generator was matched with 800 Ω resistance, the power density of the generator reached 1.74 mW/m2. The generator was able to charge a 10 μF capacitor up to 1.11 V and turn on 10 red LEDs.
In this study, the nutritional components (moisture, fat, protein, ash) value of military hardtack was collected and analyzed to control the mixing ratio of rice and flour. Hardtack from 4 factories was analyzed by 3 testing organizations certified by the Korean Ministry Food and Drug Safety. In addition, the accuracy and collaborative study possibility of each organization were evaluated in Q-test and HorRat. Also, other hardtack groups with different mixing ratios were compared to quality control of hardtack by I-MR charts. As a result, the HorRat and Q-test values of test organizations were 0.5-6.2 and 0.08-0.91, respectively. The quality of hardtack by the factories was similar. However, for accurate management of the mixing ratio, suggesting both upper and lower limit requirements of the nutritional components is necessary.
This study was conducted to investigate quality characteristics of red bean gochujang prepared with different ratios of meju for eight weeks. We determined quality characteristics such as pH, moisture content, total microbial flora counts, amino-type nitrogen content, total polypenol content, and antioxidant activity. The pH decreased by fermentation period, whereas total acidity was 0.36~0.39% in the early stage of fermentation, 0.63~1.16% at four weeks of fermentation, and decreased to 0.43~0.65% after the eighth week of fermentation. Moisture content of the control (no red bean, no rice) decreased 62.13% to 50.93%, but in case of the treatment, it slightly decreased. Total cell counts revealed similar tendency at the beginning of fermentation, and at eight weeks of fermentation. In case of lactic acid bacteria, all samples except RB-1.5 (gochujang added meju made of mixing ratio of rice:soybean:red bean (1:2:1.5) slightly increased. Amino nitrogen and total polyphenol of all samples increased in the fermentation period, especially RB-1.5 sample had the highest levels than other samples. By increasing the amount of red bean, DPPH radical scavenging activities increased. In taste sensing analysis, all treat samples except RB-1.5 revealed lower sourness than the control. Also, in case of bitterness, all samples revealed low content than the control. So, by adding red bean, it can enhance taste and function of gochujang.
This study was conducted to optimize the conditions of a sweet rice paste as a replacement of red bean paste recipe using the central composite design of response surface methodology (RSM). Ten experimental recipes with two reference points (rice flour and sugar), were selected, and the physical and sensory characteristics of a sweet rice paste were measured. In the Rapid Visco Analyzer test, breakdown value was the highest in rice flour (105.73 RVU). Sweetness significantly increased with addition of sugar contents (p<0.0002) and viscosity increased with addition of rice flour contents (p<0.0185). Moisture contents decreased with increasing contents of rice flour and sugar, whereas yellowness and redness tend to increase. In the sensory evaluation test, quadratic models for color (p<0.01865), sweetness (p<0.0399), thickness (p<0.0073), and overall acceptability (p<0.0249) were approved as independent for the rice flour and sugar contents. In conclusion, the optimal mixing ratio of sweet rice paste was determined to be 45.38 g of rice flour and 77.95 g of sugar.
FRP Hybrid Bar, composite structures composed of synthetic resins, deformed bar and glass fiber, was invented in order to solve corrosion of rebar in reinforced concrete structures. In order to bond deformed bar and glass fiber to FRP Hybrid Bar, synthetic resins is used. Curing time of the synthetic resins greatly affect productivity. If curing time of synthetic resins is short, cost of facilities is reduced and productivity is increased. Also, If this curing time is shorter or omitted, FRP Hybrid Bar can be commercialized. So, it can cause mass-production and substantial economic effect. Therefore, in this paper, optimum mix proportion is observed in order to increase economic efficiency of FRP Hybrid Bar and reduce curing time of synthetic resins. Total 9 variables are set, adjusting ratio of hardener ratio, and 3 resin moulds on each variables are fabricated. Optimum mix proportion is suggested based on data measured by temperature sensor.
The purpose of this study was to formulate the optimal ratio of tofu ice cream made with crushed tofu and soybean milk. Also, to compare characteristics of tofu ice cream and soybean ice cream. Mix viscosity, overrun and melting down are measured as characteristics of ice cream. The optimal mixing ratio of tofu ice cream was determined by response surface methodology based on overall quality. As a result of optimization, tofu ice cream was made with 65.90% tofu cream (9% solid contents), 4.35% whipping cream, 14.35% canola oil, 15.00% sugar, 0.2% emulsifier and 0.2% guar gum. Soybean ice cream made with three different treated (blanched, steamed, roasted) soybean and each preprocess are treated for 0-20 min. Mix viscosity was enhanced preprocessing time increasing. Also, overrun and melting down was decline preprocessing time increased. As a result of comparison of ice cream overall quality, 15 min roasted soybean ice cream was shown the best quality.
The purpose of this study was to formulate the optimal mixing ratio for Korean vinegared cabbages harvested in fall from Haenam, Hongseong and Gyeongsan regions. The general compositions such as moisture and ash, and hardness were not significant different among 3 cabbages. The vinegared cabbage was made with vinegar, salt and sugar, and stored at 5oC for 5 d. The diffusion of salt, sugar and vinegar to the cabbage was completed within 3 h. The optimal mixing ratio of those components was determined by response surface methodology (RSM) based on overall preference. As a result of analysis, optimal mixing ratio of Haenam vinegared cabbage was 8.94% vinegar, 1.88% salt, and 18.18% sugar, whereas 8.91% vinegar, 2.12% salt, and 17.97% sugar in Hongseong vinegared cabbage, lastly 8.24% vinegar, 2.50% salt, and 18.26% sugar in Gyeongsan vinegared cabbage. Storage characteristics were investigated at different storage times and temperatures using overall preference, texture, and pH. Overall preference and texture were enhanced after 1 wk storage, but vinegared cabbage was spoiled after 3 wk at 20oC. Change in pH was the fastest during 1 wk at all temperatures, and then reached equilibrium.
PURPOSES : This study was conducted to derive the optimum mixing ratio of phosphorescent pigment for the development of phosphorescent line marking.
METHODS: In this study, we utilized a literature review and case study methodology, to describe the domestic and foreign state of practice for the production and mixing of phosphorescent pigment for use in line marking. The optimal mixing ratio was derived by comparing the reduction in luminance over time for the various phosphorescent pigment mixing ratios identified in the literature. In addition, performance and construction characteristics were analyzed using field testing techniques.
RESULTS : The results were as follows: 1) the results of the luminance performance standards tests showed that all of the phosphorescence test specimens satisfied the phosphorescent fire protection standard. As the phosphorescent pigment mixing ratio increased, the luminance value increased, 2) the luminance reduction rate was minimum at the mixing ratio of 50%. However, when compared to a mixing ratio 40%, a small difference was recorded, the luminance reduction rate from the mixing ratio of 40% is judged as being converged. Therefore, in view of the economic efficiency, it was determined that the optimal mixing ratio was 40%, 3) as a result of construction on the field, a mixing ratio of 40% was found to have a higher luminance value than the general line marking for up to three hours after sunset, 4) it was found that the phosphorescent line markings without glass beads spraying had a higher luminance value than the phosphorescent line markings with glass beads spraying.
CONCLUSIONS : Through the results of the basic experiments of the line markings obtained by blending a phosphorescent pigment, the results could be applied to play an important role in the development of phosphorescent line marking paint technology and in establishing application planning for on-site construction characteristics.
Three different weather-resistant coatings were fabricated with the various weight ratios of a mill-base silicone/acrylic resin to let-down silicone /acrylic resin at 2:8, 3:7, and 4:6 respectively. The prepared coatings were tested to investigate the effect of composition of weather-resistant coatings on the physical properties. The thermal stability, salt spray exposure, and weather-resistance were improved with the increased silicone content. It was concluded that the optimum retio of mill-base silicone/acrylic resin to let-down silicone/acrylic resin would be 2:8 and the coating with 30 wt% of silicone content would have high weather-resistance.
Bechamel sauce의 배합비율과 방법을 달리하여 소스를 만들었을 때의 최적 조건은 다음과 같다. 1. 우유의 양과 조리 방법을 달리한 Bachamel sauce의 점도와 퍼짐성은 각각의 시료간에 유의적인 차이를 나타내었으며 (P<0.001), 점도는 우유에 첨가되는 루의 양이 적음에 따라 증가하며, 반대로 퍼짐성은 감소함을 알 수 있었다. 2. 양파 첨가 방법을 달리한 Bechamel sauce의 점도와 퍼짐성은 각각의 시료간에 서로 유의적인 차이를 나타내지 않았다(P<0.05). 3. 우유의 양과 조리 방법을 달리한 Bechamel sauce의 관능적 평가는 각각의 시료간에 유의적인 차이를 나타내었다(P<0.001). 색, 부드럽기, 전체적인 맛 등에서 높은 기호도를 나타낸 것은 버터와 밀가루 그리고 우유가 1 : 1 : 17인 것이었다. 4. 양파 첨가 방법을 달리한 Bechamel sauce의 관능적 평가에서는 점도, 부드럽기, 풍미, 전체적인 맛에서 각각의 시료간에 유의적인 차이를 나타내었으며(P<0.001), 버터에 양파를 볶아서 만드는 방법이 가장 기호도가 높았다.
본 연구는 옥상텃밭 적용을 위한 원예용상토와 펄라이트 배합비율에 따른 잎들깨의 생장반응을 조사하였다. 실험구는 직경 18cm, 높이 18cm의 플라스틱 용기에 원예용상토:펄라이트를 9:1, 7:3, 5:5, 3:7, 1:9(v/v)로 혼합한 다음 본엽이 3-4엽인 잎들깨 식재하였다. 측정항목 으로는 초장, 엽장, 엽폭, 엽수, 엽면적, 엽록소함량, 엽록소형광, 엽색, 생체중, 건물중 등의 생육 및 형태적 특성을 식재 후 4주와 8주 2회에 걸쳐 조사하였다. 초장, 엽장, 엽폭, 엽수, 엽면적은 식재 후 4주차에는 9:1 배합비에서 가장 높았으며, 그 다음으로 7:3, 5:5의 순이었다. 8주 차에는 9:1과 7:3에서 생육이 가장 양호하였으며, 전체적으로 원예용상토의 비율이 높아질수록 생육도 양호한 것으로 나타났다. 생체중과 건물중도 마찬가지로 4주, 8주차 모두 9:1에서 가장 높았으며, 그 다음으로 7:3, 5:5 순이었으며 1:9에서 가장 낮은 것으로 나타났다. 엽록소 함량은 4주차에는 9:1에서 가장 높았으며, 1:9에서 가장 낮았으나 8주차에는 1:9에서 가장 높았고 5:5에서 가장 낮은 것으로 나타났다. 엽 록소형광은 4주차에는 모든 배합비에서 차이가 나타나지 않았으나 8주차 때에는 1:9에서 0.565로 나타나 양분결핍에 의한 스트레스를 받 는 것으로 나타났다. 이상의 결과를 종합하면 옥상텃밭을 위한 잎들깨 재배시 원예용상토와 펄라이트 배합비율은 5:5 이상이 적절한 것으 로 판단된다.
본 연구는 옥상녹화 적용을 목적으로 펄라이트와 원예용상토 배합비별 비비추(Hosta longipes (Franch. & Sav.) Matsum.)를 식재한 후 무 관수 처리에 따른 스트레스가 생육에 미치는 영향을 평가하였다. 실험구는 펄라이트:원예용상토를 9:1, 7:3, 5:5, 3:7, 1:9(v/v)로 혼합한 다 음 직경 18cm, 높이 18cm의 플라스틱 용기에 본엽이 6~7매인 비비추를 식재하여 배합비별로 10반복씩 조성하였다. 측정항목으로는 초장, 엽장, 엽폭, 엽수, 엽록소함량, 엽록소형광, 녹엽면적율, 잎의 상대수분함량, 전해질 누출, 토양수분, 생존일수 등을 조사하였다. 초장, 엽장, 엽폭은 펄라이트 비율이 높아질수록 낮아지는 경향을 보였으며, 엽록소함량은 실험초기에는 펄라이트 비율이 높을수록 엽록소함량은 낮 은 경향을 보였으나 시간이 경과하면서 토양배합비율에 따른 차이는 나타나지 않았다. 용적수분함량은 실험시작 21일에는 0%에 도달하 였으며, 그 감소폭은 펄라이트 비율이 높을수록 낮은 경향을 보였다. 엽의 전해질누출은 수분스트레스로 인해 고사직전에 증가하는 경향 을 보였다. 생존일수는 7:3 배합비에서 53.3일로 가장 길었으며, 그 다음으로 9:1이 53.0일, 5:5 48.0일, 3:7 43.7일이었으며, 1:9에서는 40.3 일로 가장 빠르게 고사하는 것으로 나타나 펄라이트 비율이 높을수록 생존기간이 길어지는 것으로 나타났다. 이는 펄라이트의 높은 보수 력이 반영된 결과로 판되며, 펄라이트 비율이 높아질수록 생육적인 측면에서는 불리한 경향을 나타내 5:5 또는 3:7배합비율이 식물생육 측 면에서는 바람직한 것으로 판단된다.
This study was conducted to investigate the influence of hydrophilic polymer (HP) mixture ratio (Control, 1.0%, 2.5%, 5.0%, and 10.0%) on growth of eggplant (Solanum melongena) for lower maintenance urban agriculture via green roofs. Although it was not statistically significant (p > 0.05), substrate temperature was decreased as hydrophilic polymer mixture ratio were increased. High substrate water content (95%) was found consistently in growing media under elevated hydrophilic polymer mixture ratio at over 5% during the entire growing period. Substrate electronic conductivity was increased as hydrophilic polymer mixture ratio were increased. Growth index was decreased as hydrophilic polymer mixture ratio was increased. It was reduced about 1/3 and 1/5 compared to that of Control in HP5.0 and HP10.0 treatment plants, respectively. Number of leaves, leaf length, and leaf width were decreased in following order: Control> HP1.0> HP2.5> HP5.0> HP10.0 treatments. There numbers were significantly lower in HP5.0 and HP10.0 treatment plants. Dry weight of shoot and root were decreased as hydrophilic polymer mixture ratio was increased. They were reduced by 1/4 compared to those of Control treatment plants. In addition, visual value was decreased as hydrophilic polymer mixture ratio was increased. Plants grown in HP1.0, HP2.5, and HP5.0 treatments all survived. However, plants grown in the HP10.0 treatment had the lowest survival rate (56%) after 3 months of growing. These results indicate that the advantage of adding hydrophilic polymer to green roof growing media may greater during dry periods. However, the proper mixture proportion of hydrophilic polymer should be determined according to different characteristics of growing media and plant species.
본 연구는 고로슬래그 미분말 (GGBFS),플라이애시 (FA) 그리고 실리카 퓸( SF)을 각각 세 종류와 네 종류로 시멘트와 혼합한 다성 분계 시멘트의 특성 연구에 관한 것이다. 물-결합재 비는 0.45 이다. 본 연구에서는 혼화재료를 시멘트의 50%와 60% 비율의 두 가지로 치환하 였으며, 각 배합에 대해서 GGBFS는 20~40%, FA는 5~35% 그리고 SF는 0~10%를 배합하여 기초특성에 관한 실험을 수행하였다. GGBFS/FA 비와 SF 치환율에 따른 다성분계 시멘트에 대해 압축강도, 물 흡수율, 초음파 속도 (UPV), 건조수축 그리고 XRD 분석을 수행하였다. 실험결과 SF를 치환함에 따라 흡수율은 감소하고 압축강도, UPV와 건조수축은 증가하였다. 이러한 압축강도, 흡수율 그리고 UPV 등의 결과는 SF의 혼 합률이 증가함에 따라 용출된 수산화칼슘을 소비하여 CSH의 형성에 기여하기 때문이다. 각 SF 혼합률에서 GGBFS/FA 비가 증가함에 따라 강도, 흡수율 그리고 UPV도 증가하였다. GGBFS/FA 비와 강도, 흡수율, UPV는 선형적인 관계를 나타내었다. 본 연구를 통해 GGBFS/FA비와 SF 치환율은 다성분계 시멘트의 기초 특성에 중요한 요소임을 발견할 수 있었다.
Many researches are conducted on the concrete pannel to improve the capacity. Up to now, however,the surface glossing of concrete pannel is rarely executed. So it is needed to investigate the surface glossing of concrete pannel. In this paper, the mechanical properties and surface condition of the concrete pannel was compared with water content and aggregate ratio. From the results, when aggregate ratio increase, compressive strength and flexural strength decrease. And, the surface glossing of Non AE concrete pannel was better than that of AE concrete pannel.
CO₂는 온실효과에 주된 원인으로 기후 변화에 대한 기여율이 약 65%이다. 이 중 시멘트 산업에서의 CO₂ 배출이 전체 CO₂의 6%를 차지하는 것으로 알려져 있어 시멘트 생산과정에서의 CO₂ 배출량을 획기적으로 줄일 수 있는 대책들이 필요하다. 그 대책 중 하나로서 산업부산물을 이용한 지오폴리머가 각광받고 있다. 지오폴리머는 산업부산물들을 이용하기 때문에 CO₂ 발생량이 낮아 친환경 대체자원으로 국내‧외에서 많은 연구가 진행되고 있다. 본 연구에서는 메타카올린(MK)과 플래이애쉬(FA)를 이용한 고강도 지오폴리머를 제조하기 위해 반응표면분석법으로 최적 배합비를 산출하였다. 중심합성계획법을 이용하여 실험조건을 결정하였으며, 적용한 독립변수와 그 범위는 각각 플라이애쉬(FA) 첨가율(FA혼합율, 전체 무기성재료에 대한 FA의 질량 백분율, %) 0 ~ 50%, 알칼리활성화제 비(AE%, 전체 무기성재료에 대한 Na₂O 질량 백분율, %) 10 ~ 25, Silicate modulus (Ms., SiO₂/Na₂O 질량 비) 0.5 ~ 1.5이다. 시편은 고온・상온양생 후 7일, 28일 압축강도를 측정하였다. 7일 및 28일 압축강도는 FA혼합율 25.0%, AE% 17.50, Ms.1.0 일 때 각각 94.2 MPa, 98.8 MPa로 가장 높게 나타났으며, 7일 이후 압축강도 증가는 크지 않았다. 압축강도 결과를 이용하여 2차 모형 회귀분석, 분산분석, 정준분석을 실시하여 최적 배합조건을 도출하였다. 7일 압축강도 결과 값을 이용한 2차 모형으로 회귀 분석한결과 아래와 같은 식을 얻을 수 있었다.
y=84.809-8.933x₁+3.882x₂+17.092x₃-1.086x₁²-18.288x₂²
-12.614x₃²-4.828x₁x₂-1.027x₁x₃-2.552x₂x₃
x₁,x₂,x₃는 각각 FA혼합율, AE%, Ms.이며, 분산분석 결과 2차 모형 회귀식 및 1차항, 2차항의 회귀계수 모두 유의수준 0.05 수준에서 유효한 것으로 나타났으며, 적합성 결여 검정에서도 모델식이 유효한 것으로 판정되었다. 실험범위 내에서의 최적 배합비는 FA혼합율 0.0%, AE% 18.79, Ms. 1.2이며, 105.2 MPa의 압축강도를 얻을 수 있었다. 정준분석 결과 정상점은 최대점이며, (-6.538, 0.910, 0.852)로 파악되었다. 이로부터 정상점은 실험범위를 벗어난 영역에 존재함을 알 수 있다. 28일 압축강도 결과 값을 이용한 2차 모형 회귀분석 결과 아래와 같은 식을 얻을 수 있었다.
y=90.6873-11.0202x₁+1.9121x₂+16.57243x₃-2.6492x₁²-22.3598x₂²
-12.7944x₃²-4.7325x₁x₂-0.3950x₁x₃-4.1575x₂x₃
분산분석 결과 2차 모형 회귀식 및 1차항, 2차항의 회귀계수 모두 유의수준 0.05 수준에서 유효한 것으로 나타났으며, 적합성 결여 검정에서도 모델식이 유효한 것으로 판정되었다. 실험범위 내에서의 최대 28일 압축강도는 배합비 FA혼합율 0.0%, AE% 18.18, Ms. 1.2의 조건에서 108.1 MPa을 얻을 수 있는 것으로 나타났다. 정준분석 결과 정상점은 최대점이며, (-2.333, 0.230, 0.655)로 나타났다. 이로부터 정상점이 실험범위를 벗어난 영역에 존재함을 알 수 있다.
In this study, wheat doenjang was manufactured using Korean wheat meju and soybean meju, and its quality were investigated according to mixing ratio of meju. The general characteristics such as moisture contents, pH and salinity of wheat doenjang, which is fermented and aged at 25℃ for 70 days, were slightly decreased time dependently as similar pattern. The pH of wheat doenjang ranged from 4.95 to 5.11% and generally ecreased with aging. The moisture contents was 54.5~57.5%, and there was no significant differences in the aging period. Also, there was no significant changes in the salt contents. The amino-type nitrogen contents were 376.27~600.91 mg% at day 70 of the aging period, and showed 3 fold change compared to the initial contents. The reducing sugar contents showed significant difference between the samples, and repeated fluctuation in the aging period. Wheat meju sample A, which contains 50% of soybean meju, showed the highest antioxidation ability. In addition, wheat meju sample A showed the highest score in the sensory evaluation of the colour, taste, flavor, and overall acceptability. Therefore, wheat doenjang manufacturing at a 1:1 of mixing ratio will lead to desirable quality of wheat doenjang.