• 동아시아식생활학회지
• /
• 제23권2호
• /
• pp.218-226
• /
• 2013

This study examined the optimal mixture ratio of rice gruel supplemented with puffed rice by mixture design. The quality characteristics of rice gruel samples were examined according to mixture ratios at eleven experimental points. The high soluble solid content and viscosity of gruel samples were significantly dependent on rice (short grain) content instead of glutinous rice. The viscosity ranged from $2,891{\sim}9,153\;cP{\cdot}s$ and soluble solid content ranged from $8.23{\sim}10.13^{\circ}Brix$ at the eleven experimental points. The mixture with the highest solid content and viscosity, 12% rice gruel sample was $10.10{\sim}10.13^{\circ}Brix$ and $9,150{\sim}9,153\;cP{\cdot}s$. The L color of sample decreased with decreasing rice content, while "a" (redness) and "b" (yellowness) values slightly increased. In the sensory evaluation, samples with higher amount of puffed rice and glutinous rice scored higher for brown color, flavor and sweetness than high-content rice samples. The response surface and trace plot results showed that increasing of puffed rice increased the brown color, sweet taste and sticky aftertaste. From the results of the F-test, viscosity, "a" (redness) and "b" (yellowness) values fit a quadratic model with significant probabilities within 0.05%. The optimum predicted formulations of rice gruel containing puffed rice were 1.69% of puffed rice, 0.47% of glutinous rice and 9.84% of rice, respectively.

• 한국식품과학회지
• /
• 제35권4호
• /
• pp.617-622
• /
• 2003

두유박 시리얼을 제조하는데 최적 배합비를 산출하기 위하여 혼합물 실험 계획법을 사용하였다. 두유박 $30{\sim}80%$과 옥분 $20{\sim}70%$의 제약조건으로 실험디자인을 하여 압출성형을 한 결과, 두유박 함량이 증가할수록 시리얼의 팽화율은 작아지고 용적 밀도는 높아진 반면에 옥분의 함량이 증가할수록 팽화율과 절단강도, 수분용해지수, 수분흡수지수를 증가시켰다. 시리얼의 색도에서는 두유박을 첨가할수록 어두워지고, 옥분은 $L^*$값과 $b^*$값에 큰 영향을 주었다. 모델화 및 분석을 통한 반응 결과는 팽화율, 절단강도, 수분흡착지수는 quadratic 모델이 설정되고, 용적밀도, 수분용해지수, 색도는 linear 모델이 설정되었다. 색도의 $a^*$을 제외한 모든 반응결과에서 5% 이내의 유의차를 보여주어 모델에 대한 적합성을 입증하였고, 예측된 반응식을 통하여 혼합물내의 성분들이 시리얼에 미치는 영향을 살펴볼 수 있었다. 결과적으로 각 반응의 모델에서 나타난 계수를 이용한 수치 최적화를 하였을 때, 두유박 46.19%, 옥분 53.81%의 최적 배합비가 산출되었다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
• /
• pp.141-144
• /
• 2006

The main purpose of this study is to develop a Sprayed FRP repair and strengthening method, which is a new technique for strengthening the existing concrete structures by mixing carbon or glass shot fibers and the epoxy or vinyl ester resins with high-speed compressed air in open air and randomly spraying the mixture onto the concrete surface. At present, the Sprayed FRP repair and strengthening method using the epoxy resin has not been fully discussed. In order to investigate the material property of Sprayed FRP, this study carried out tensile tests of the material specimens which are changed with the combinations of various variables such as the length of shot fiber and mixture ratio of shot fiber and resin. These variables are set to have the material strength equal to one layer of the FRP sheet. As a result, the optimal length of glass and carbon shot fibers were derived into 3.8cm, and the optimal mixture ratio was also deriver into 1:2 from each variable. And also, the thickness of Sprayed FRP to have the strength equal to one layer of FRP sheet was finally calculated.

• 한국환경과학회지
• /
• 제29권8호
• /
• pp.793-800
• /
• 2020

The conventional development of multi-component electrodes is based on the researcher's experience and is based on trial and error. Therefore, there is a need for a scientific method to reduce the time and economic losses thereof and systematize the mixing of electrode components. In this study, we use design of mixture experiments (DOME)- in particular a simplex lattice design with Design Expert^Ⓡ program- to attempt to find an optimum mixing ratio for a three-component electrode for the high RNO degradation; RNO is an indictor of OH radical formation. The experiment included 12 experimental points with 2 center replicates for 3 different independent variables (with the molar ratio of Ru, Ti, Ir). As the Prob > F value of the 'Quadratic' model is 0.0026, the secondary model was found to be suitable. Applying the molar ratio of the electrode components to the corrected response model results is an RNO removal efficiency (%) = 59.89 × [Ru] + 9.78 × [Ti] + 67.03 × [Ir] + 66.38 × [Ru] × [Ir] + 132.86 × [Ti] × [Ir]. The R² value of the equation is 0.9374 after the error term is excluded. The optimized formulation of the ternary electrode for an high RNO degradation was acquired when the molar ratio of Ru 0.100, Ti 0.200, Ir 0.700 (desirability d value, 1).

• 한국습지학회지
• /
• 제3권1호
• /
• pp.75-89
• /
• 2001

Constructed wetlands were typically cost less to build and operate, and require less energy than standard mechanical treatment technology but they have similar performance to centralized wastewater treatment plants. Therefore, they were constructed especially many in rural areas, where are small villages but not industries. Accordingly, plantless column tests were performed to investigate the possibility on using zeolite as a filter medium of constructed wetland for the wastewater treatment. $COD_{cr}$ removal efficiency was 94.63% at hydraulic load $314L/m^2{\cdot}d$ and filtering hight 100cm filled with a zeolite mixture. This zeolite mixture consisted of 1 : 1 by volume of a zeolite in the diameter range of 0.5 to 1mm to a zeolite in the diameter range of 1 to 3mm. According, hydraulic load $314L/m^2{\cdot}d$ was considered as optimal. Three zeolite mixture were used to determine the optimal mixing ratio by volume of a zeolite(A) in the diameter range of 0.5 to 1mm to a zeolite(B) in the diameter range of 1 to 3mm diameter. 1 : 3, 1 : 1 and only B in A to B by volume were tested at hydraulic load $314L/m^2{\cdot}d$ and filtering hight 100cm. $COD_{cr}$ removal efficiency was more than 89% at mixing ratios of 1 : 3 and 1 : 1 in A to B. Removal efficiency was lower at the column filled with only B. Removal efficiency was better at filter medium filled with mixing ratio 1 : 1 in A to B than with the other mixing ratios. Thus, it was found that the mixture of mixing ratio 1 : 1 in A to B was appropriate for filter medium of constructed wetland. Removal efficiency was higher in down-flow than in up-flow, and $COD_{cr}$ and BOD were removed best in 20cm filter height near feeding area.

• 한국대기환경학회지
• /
• 제17권5호
• /
• pp.407-414
• /
• 2001

In this study, the absorption kinetics of $CO_2$onto a mixture of AMP (2-amino-2-methyl-1-propanol) MEA (monoethanolamine) water were investigated at 30 and 4$0^{\circ}C$ using a packed absorption tower. Solubility and absorption rate of $CO_2$into alkanolamine solutions and optimal condition of $CO_2$absorption process were investigated. The experimental conditions are as follows; temperature of 30 and 4$0^{\circ}C$, gas flow rate of 3ι/min for the absorption tower, and liquid flow rate of 0.1ι/min. Feed gas was a mixture of 85% $N_2$and 15% $CO_2$. The experimental results showed that AMP had greater solubilities and faster absorption rates than MEA and DEA. In addition, MEA had the fastest initial reaction rate. To improve the properties of AMP which have low initial reaction rate and high cost, AMP was used with MEA. The mixing ratio was also changed in constant total molarity of 1,2,3 and 4. The experimental results can be summarized as follows: (1) in solubility experiment, the addition of MEA in constant total polarity decreased the solubility of $CO_2$in AMP/MEA mixture. (2) from 0 to about 0.3 in mixing ratio, the solubility of $CO_2$in AMP/MEA mixture had little differences compared with the sum of solubility of AMP only and solubility of MEA only . (3) mixing ratio of 0.3 was found to be an optimal point with the fastest $CO_2$absorption rate.

• 한국환경복원기술학회지
• /
• 제2권2호
• /
• pp.33-42
• /
• 1999

The objective of this study was to determine the optimal amount and the mixture ratio of seeds for revegetation species by investigating their growth characteristics. For the purpose of the experiments, 15 plants were chosen. In May of 1995 to September of 1998, the nursery seedbeds of the College of Agriculture and Life Sciences, Seoul National University were seeded with the mixtures of those species. Then, the nursery seedbeds were treated to investigate the effects of the amount of seeding, the amount of fertilizer, and the depth of soil on the growth characteristics. As the results of the experiments, it was found that the effects of all the treatments on growth of shoots and roots were significant in the early phase. For the expected number of seedlings more than 3,000 per square meter, many seedlings got withered to death while the survivors were suppressed to grow slow in the early stage due to the density problem.

• 동아시아식생활학회지
• /
• 제22권6호
• /
• pp.782-794
• /
• 2012

The objective of this study was to determine the optimal conditions for preparation of cooked brown rice by blending brown rice, white rice and glutinous rice to improve the palatability. Formulations composed of brown rice (10~100%), white rice (0~90%) and glutinous rice (0~90%) were generated from an extreme-vertices of mixture experimental design, which showed ten experimental points for brown rice, with white rice and glutinous rice as the independent variables. The sensory evaluation, color, and texture profile analysis (TPA) of cooked brown rice and pasting characteristics of blending cereals flour were measured as response variables. Regression analysis showed that all responsible variables fit linear, quadratic or special cubic models (p<0.1), except for the cohesiveness of TPA. The goals of optimization of the blending ratio of brown rice, white rice and glutinous rice were given as appearance, flavor, texture and overall acceptability (lower: 5.50, target: 6.62). The optimal conditions were determined to be 34.55% brown rice, 42.71% white rice and 22.74% glutinous rice.

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 2017년도 춘계공동학술대회
• /
• pp.101-101
• /
• 2017

Beta-glucan is a polymerized polysaccharide on beta-1,3 chemical bonds. It has the main pharmacological action of various anticancer mushrooms and is colorless and odorless. In addition, it enhances phagocytosis of macrophages against mycobacterium tuberculosism and increases resistance of host against food poisoning bacteria. Owing to these advantages, beta-glucan was used in various health supplement foods such as immune boosters, hypotensive agent and hypoglycemic agent. Our study was aimed to investigate the effective components of beta-glucan, which was optimized via the contents of Sarcodon aspratus and rice bran. First, the mixture ratio condition of Sarcodon aspratus and rice bran were respectively 10:0, 7:3, 5:5, 3:7, and 0:10. The raw materials were fabricated using hot water extraction method. Distilled water of 100 mL was added to the raw material and extracted. After the extraction processed, the content of effective components was analyzed. The absorbance of beta-glucan was measured using a beta-glucan kit (Megazyme, (1-3) (1-4) BETA-D-GLUCAN ASSAY KIT). The absorbance analysis was repeated three times for accurate analysis. After the extracts were lyophilized, the yields of extracted raw materials according to the mixture ratio conditions of Sarcodon aspratus and rice bran (10:0, 7:3, 5:5, 3:7, and 0:10) were respectively 33.1%, 34.5%, 35.3%, 30.7%, and 24.3%. The absorbance was 1.52, 1.47, 1.50, 1.79, and 1.56, respectively. As a result, the optimum ratio of beta-glucan is 3:7 at Sarcodon aspratus and rice bran. This study suggested that the optimal amount of beta-glucan could be used as a health supplement foods and food additive such as immune boosters, hypotensive agent and hypoglycemic agent. However, the new condition (temperature, time) of hot water extraction to maximize the content of beta-glucan could be considered, could be necessary to compare with the existing extracts.

• 응용통계연구
• /
• 제35권1호
• /
• pp.77-91
• /
• 2022

의학통계와 신용평가 분야에서 혼합분포함수를 판별하는 최적분류점 추정하기 위하여 판별력을 측정하는 다양한 정확도 측도들이 존재한다. 최근에 혼동행렬 빈도수로 표현되는 Matthews의 상관계수와 정밀도와 재현율의 조화평균인 F1 통계량의 정확도 측도들이 최적분류점을 추정하는데 연구되었다. 본 연구에서는 이런 정확도 측도들 중에서 표본크기에 의존하는 정확도 측도들은 두 표본크기 차이가 많은 경우에 최적분류점을 설정하는데 적절하지 않음을 발견한다. 그리고 대안적인 정확도 측도로 혼동행렬의 비율들의 함수인 상관계수를 정의하고, 이를 최대화하는 분류점을 최적분류점으로 추정하는 방법을 제안하고 이 방법의 유용성과 활용성에 대하여 토론한다.