교통량이 증가하고 교량과 같은 특수구조물에 아스팔트 포장이 시공되는 사례가 증가함에 따라 일반적으로 사용되는 아스팔트보다 높은 성능을 가진 아스팔트에 대한 수요가 증가하고 있다. 일반 아스팔트 혼합물은 내구연한이 지나면 재생첨가제 등을 사용하여 다 시 도로포장재료로서 재활용할 수 있는 방안이 마련되어 있으나, 개질 아스팔트가 사용된 폐아스팔트 혼합물은 매립재로 사용하는 것 이외에는 별다른 대안이 없는 실정이다. 이에 본 연구에서는 국토부 지침에 규정된 재활용 아스팔트 혼합물 배합설계법을 적용하여 개질 폐아스팔트 혼합물을 재활용할 수 있는지를 검토해보고자 하였다. 이를 위해 개질 아스팔트를 활용하여 혼합물을 제작하였으며, 현장에서 수거되는 폐아스팔트 혼합물의 노화상태를 모사하기 위해 AASHTO R 30을 참고하여 강제 노화를 실시하였다. 노화 및 추출 과정에서 아스팔트의 물성 변화를 확인하기 위해 절대점도, DSR, MSCR 시험을 실시하였다. 시험결과, 추출 후 바인더의 절대점도는 감소하였으나 G*(복합전단계수)와 δ(위상각)은 증가하는 경향을 보였다. 소성변형 저항성을 확인하기 위해 MSCR(다중 응력 크리프 및 회복) 시험을 실시한 결과, 이 2배 가까이 증가하여 소성변형 저항성이 감소한 것을 확인할 수 있었다. 이러한 결과는 추출시 사용 되는 용매가 개질첨가제를 추출하지 못하여 기인한 결과로 판단된다. 따라서 개질 폐아스팔트 혼합물을 재활용하기 위해서는 기존과 는 다른 별도의 배합설계법이 개발되어야 할 것으로 판단되었다.
PURPOSES : The aim of this study is to investigate the enhancement of performance and the mix design method for asphalt mixtures utilizing ferronickel slag, an industrial by-product METHODS : To enhance the performance of FNS asphalt, waste tire powder (CR) was incorporated, and the characteristics of FNS asphalt aggregate, along with the impact of CR, were evaluated through the mix design process. RESULTS : CR is found to be suitable with a size of 30 mesh, and the optimal usage amount is determined to be 1±0.1% of the mixture weight, considering dense grade asphalt mixture. Volumetric design considering the swelling characteristics of CR is necessary, and a mixing design with a consistent tendency can be achieved only when an appropriate VMA is secured. CONCLUSIONS : The mix design for FNS-R asphalt mixture requires an increase of approximately 1% in VMA compared to conventional dense-graded asphalt mixtures to accommodate the swelling of CR. Additionally, FNS-R asphalt exhibits improved resistance to rutting comparable to modified asphalt and meets quality standards, including stripping resistance.
The study aims to analyze the mixed characteristics of knit fashion design as demonstrated in Sacai's collection, which promotes hybrid and mesh-up fusion and proposes various knit design ideas. Standards for categorizing mixed phenomena of Sacai’s knit design were established through a review of literature and data analysis. The study’s data collection period was from 2012 to 2021, and a total of 174 items were analyzed. The following are the results. First is the fusion of traditional knit and contemporary styles expressed through de-constructive design; traditional knit styles are combined with contemporary styles through color, material, and knitting structure mixtures, such as mixing Northern European Aran, Fair Isle, Nordic, and Ropy knit. Second, the Sakai knit design combines male and female styles by mixing materials and details. A deconstructed knit cardigan was matched with androcentric pin-striped shirts worn over layered shirring skirts embellished with chiffon and lace. Third, everyday street fashion style is blended with a formal, elegant fashion style. For example, the front view has a typical everyday appearance, whereas the back view contains florid and decorated details. The style is expressed as a 360-degrees appellation, with one thing in the front and another in the back. Sacai’s distinctive expressional characteristics include a mixed and de-constructive style characterized by unexpected design.
PURPOSES : In many European countries, the fine-size exposed aggregate concrete pavement (EACP) technique has been adopted for a quiet pavement. However, different noise reduction levels were reported based on the mixture design and texture conditions. This study aims to suggest a quality control condition for achieving low-noise texture and a mixture design procedure for exposed aggregate concrete overlay (EACO), which will provide the optimum mixture of the surface texture that can reduce the tire-pavement noise.
METHODS : The tire-pavement noise is highly influenced by the pavement surface texture. The surface texture of the EACP can be quantified by the mean texture depth (MTD) and the exposed aggregate number (EAN). The optimum condition for the low-noise texture of the EACP was investigated herein based on the analysis of the review of the texture conditions and noise measurement in many EACP sites.
RESULTS : The MTD and EAN criteria can be derived according to the investigated relationship between noise and texture condition. The optimum mixture design to satisfy these criteria can be achieved by controlling the maximum size of the coarse aggregate and the S/a.
CONCLUSIONS: This study aimed to suggest a quality control condition for achieving low-noise texture and an optimum mixture design for EACO. As a result, we found that the early traffic opening of EACO can be achieved by using high early-strength cement.
PURPOSES : In Korea, asphalt overlay has been used as a typical alternative rehabilitation method for deteriorated pavements. However, asphalt overlay has problems due to poor bonding of the asphalt overlay and the old concrete. Recently, concrete overlays, which have advantages such as long-term durability and high structural capacity to carry heavy traffic, have been considered for rehabilitation construction. However, concrete overlays have limitations such as difficulty in opening to traffic and pavement noise. Recently, an appropriate fine-size exposed aggregate concrete pavement technique was reported to solve these problems. Therefore, this study aims to suggest an optimum mixture design of fine-size exposed aggregate concrete overlay (EACO) that can ensure low noise and early strength.
METHODS : The optimum mixture design of fine-size EACO is determined to ensure adequate structural performance for early traffic opening and good functional performances such as low noise. Therefore, the optimum mixture proportion is determined based on the optimum design of aggregate content to produce a low-noise pavement texture by controlling the exposed aggregate number (EAN) and mean texture depth (MTD).
RESULTS : The water-cement ratio and unit cement ratio were used to determine the mixture designs to achieve workability and adequate strength for early traffic opening. The texture was determined by selecting the maximum size of coarse aggregate smaller than 10 mm with an S/a ratio of less than 30% for low noise. With these mixture proportions, the EAN and MTD were 50±5 / 25cm2 and 1.0±0.2 mm. Respectively, which meet the criteria for EACO.
CONCLUSIONS: In this study, an optimum mixture design of EACO for early traffic opening and low noise is suggested by using earlyhigh strength cement, and the pavement texture is implemented considering EAN and MTD. In addition, a pavement surface texture criterion is suggested for the quality control of EACO.
Purple-fleshed potato powder (PFPP) was investigated to determine optimal mixing ratio with milk powder and dextrin to produce a ready-to-eat mashed potato powder. The rheological characteristics, color, and anthocyanin contents were studied at a different concentration of ingredients. The power-law model was applied to explain the mechanical spectra of mashed potatoes which represented the change in structure induced by different mixing ratios. Mixture design was used to obtain the experimental points used to establish the empirical models to describe the effects of each ingredient on the characteristic of the mashed potato. The results of mechanical spectra showed that both storage and loss moduli (G' and G'') were significantly influenced by PFPP and milk powder concentration. The power law parameters n' and n'' showed higher values for the mashed potato with a lower concentration of PFPP and a higher concentration of milk powder, which showed that the gel networks involved in the mashed potato were weaker. The optimum mixing ratio with the highest redness and anthocyanin content, while maintaining the rheological properties similar to the commercial mashed potato, was determined as PFPP:milk powder:dextrin = 90.49:4.86:4.65 (w/w). The proportions of PFPP and milk powder in the formulation significantly changed the characteristics of mashed potato, whereas no significant effect of dextrin was observed in this formulation.
Purple-fleshed potato powder (PFPP) was investigated to determine optimal mixing ratio with milk powder and dextrin to produce a ready-to-eat mashed potato powder. The rheological characteristics, color, and anthocyanin contents were studied at a different concentration of ingredients. The power-law model was applied to explain the mechanical spectra of mashed potatoes which represented the change in structure induced by different mixing ratios. Mixture design was used to obtain the experimental points used to establish the empirical models to describe the effects of each ingredient on the characteristic of the mashed potato. The results of mechanical spectra showed that both storage and loss moduli (G' and G'') were significantly influenced by PFPP and milk powder concentration. The power law parameters n' and n'' showed higher values for the mashed potato with a lower concentration of PFPP and a higher concentration of milk powder, which showed that the gel networks involved in the mashed potato were weaker. The optimum mixing ratio with the highest redness and anthocyanin content, while maintaining the rheological properties similar to the commercial mashed potato, was determined as PFPP:milk powder:dextrin = 90.49:4.86:4.65 (w/w). The proportions of PFPP and milk powder in the formulation significantly changed the characteristics of mashed potato, whereas no significant effect of dextrin was observed in this formulation.
Sea cucumber (SC) or Stichopus japonicas is widely used in East Asia as a traditional medical component for the treatment of asthma, arthritis, and sinus congestion. The hydrolysate of SC (HSC) after treatment with a protease is also widely used as an ingredient for processed food application such as noodles. Tensile force and deformation are important texture properties of noodle. The peptides prepared by hydrolyzing SC could affect the tensile properties of noodle, as well as DPPH radical scavenging. The objectives of this study were to characterize the tensile properties, the texture properties, color, and DPPH radical scavenging of noodle with HSC and to determine an optimum formulation of dough with HSC for noodle. The HSC was prepared by hydrolyzing dried SC powder with distilled water (DW) and a protease, Protamex (Novozyme Nordisk, Bagsvaerd, Danmark). The tensile properties and antioxidant activity were used as major constraint functions for the optimization. The optimum ratio was determined as flour:water:HSC=69.27:22.48:7.05 (w/w). Increasing the amount of HSC in the formulation increased the tensile force but no significant difference was observed in the deformation.
국내산 고구마를 이용하여 고품질의 고구마 막걸리를 개발하기 위해 다양한 방법의 고구마 막걸리 제조 방법 선정과 믹스쳐 디자인을 이용한 고구마 막걸리의 최적 배합비를 산출하였다. 엿기름 첨가 유무에 따른 혼합당화, 분리당화발효법을 이용하여 고구마 막걸리를 제조한 결과, 동시당화발효를 이용하여 고구마 막걸리를 제조하는 것이 적합함을 확인하였다. 최적의 고구마 막걸리 배합비를 구하기 위하여 쌀, 고구마, 물 세 가지 재료 요인으로 mixture design을 이용하여 다양한 배합비를 결정한 후, 고구마 막걸리를 제조하였다. 또한 제조된 고구마 막걸리의 선호도, 총 폴리페놀 함량, DPPH 라디칼소거능을 측정하여 통계적 모델링과 분석을 하였고, trace plot 및 contour plot을 이용하여 각 재료의 함량이 반응값에 미치는 영향을 확인할 수 있었다. 프로그램에 의해 예측된 고구마 막걸리의 최적 배합비는 15.11(쌀) : 44.89(고구마) : 40(물)이었으며, 이 배합비에 따른 반응값의 예상치는 선호도 6.17, 총 폴리페놀 함량이 414.95 ㎎ GAE/ℓ, DPPH 라디칼 소거능은 38.02%로 예측되었다. 최적배합비를 바탕으로 일반고구마, 호박고구마, 자색고구마를 이용하여 고구마 막걸리를 제조한 결과, 호박고구마 막걸리의 알코올 함량이 5.83%로 가장 높게 나타났으며, 총 폴리페놀 함량과 DPPH 라디칼 소거능은 자색고구마 막걸리>호박고구마 막걸리>일반고구마 막걸리의 순서로 높게 나타났다.
혼합물실험계획법(mixture experimental design)을 적용하여 라면 밀가루 혼합비를 최적화하였다. 밀가루 혼합비를 최적화하기 위하여 전체 기호도(overall palatability)의 최대화, 반죽 레올로지 특성의 특정 범위 유지를 최적화의 목적으로 설정하였다. 라면은 가장 보편적인 미국산 밀가루 중 강력분인 DNS, 중력분인 HRW, 박력분인 SW를 simplex-lattice 방식에 의해 혼합비를 달리하여 제조하였다. 각 시료는 Rapid Visco Analyser(RVA), 파리노그래프, 익스텐소그래프를 이용하여 반죽의 레올로지 특성치를 측정하였으며, 조리된 라면의 전체 기호도를 관능 검사 하였다. 정준상관분석(canonical correlation analysis)를 통하여 RVA의 최고점도(PV), 파리노그래프의 반죽형성시간(DT), 익스텐소그래프의 R/E 45 min을 주요 반죽 레올로지 특성치로 선발하였다. 최적화 목적으로 전체 기호도의 최대화와 최고점도(PV)(최대화), 반죽형성시간(DT)(최소화) 및 R/E 45 min(최대화)를 지정하였다. 그 결과 최적화된 밀가루 혼합비는 DNS 33.3%, HRW 33.3% 및 SW 33.3% 이였으며, 이때 전체 기호도는 5.825, 최고점도(PV)는 587.9 cP, 반죽형성시간(DT)은 3.1 min, R/E 45 min는 2.339 BU/mm로 나타났다.
환경보호에 부응하고 고에너지효율성을 갖춘 중온아스팔트혼합물이 가열아스팔트혼합물의 대안으로 부각되고 있다. 본 연구의 목적은 아스파민을 혼합하여 제조한 중온아스팔트혼합물을 실험적으로 평가하고, 역학적-경험적 포장설계법인 MEPDG를 이용하여 설계한 결과를 일반아스팔트혼합물 설계와 비교하는 것이다. 실험재료는 최대공칭치수 12.5mm인 골재와 PG64-28바인더가 사용되었으며, 기존 혼합물, 0.3%와 0.5%의 아스파민을 혼합한 중온아스팔트혼합물에 대한 회복탄성계수실험이 실시되었다. 실험결과를 MEPDG 설계의 입력변수로 하여 분석한 결과, 아스파민을 사용한 중온아스팔트혼합물의 소성변형량이 일반혼합물에 비해 훨씬 적어 소성변형에 대한 저항성이 향상됨을 알 수 있었다.
생강이 가지고 있는 항산화력을 최대화 시키기 위해 다양한 제조 공정에서 흑생강을 제조하였다. 증숙 온도 및 시간에 따른 DPPH radical 소거능을 측정하였고, 이를 반응표면 분석법에 의해 최적화된 제조 공정을 선정하였다. DPPH radical 소거능을 최대화 할 수 있는 최적 점을 설정한 결과 93.2oC에서 6시간의 증숙 공정이 설정되었다. 제조한 흑생강을 음료로 개발하기 위해, 매실 농축액과 꿀을 혼합하여 기능성과 선호도가 높은 음료를 제조하였다. DPPH radical 소거능, 플라보노이드 함량, 관능평가의 canonical 계수를 이용하여 수적 최적화를 통하여 최적 배합비를 구한 결과, 흑생강 추출물 14.2%, 매실농축액 5%, 꿀 10.8%로 나타났고 desirability가 0.615로 설정되었다. 이때의 종속 변수값들은 DPPH radical 소거능 46.0 mg/L, 플라보노이드 함량 29.9 mg/L, 선호도 5.284로 예측되었다.
In this study, the additivity factors of compositions to density and glass transition point (Tg) in a xLi2O-(1-x)[(1-y)TeO2-yZnO] (0<x<20, 0<y<20) glass system were analyzed by using mixture design, and the change of ionic conductivity with density and Tg was discussed. As a method for predicting the relation between glass structure and ionic conductivity, density was measured by the Archimedes method. The glass transition point was analyzed to predict the relation between ionic conductivity and the bonding energy between alkali ions and non-bridge oxygen (NBO). The relation equations showing the additivity factor of each composition to the two properties are as follows: Density(g/cm3) = 2.441x1 + 5.559x2 + 4.863x3 Tg(˚C) = 319x1 + 247x2 + 609x3 - 1950x1x3 (x1 : fraction of Li2O, x2 : fraction of TeO2, x3 : fraction of ZnO) The density decreased as Li2O content increased. This was attributed to change of the TeO2 structure. From this structural result, the electric conductivity of the glass samples was predicted following the ionic conduction mechanism. Finally, it is expected that electric conductivity will increase as the activation energy for ion movement decreases.
There are several methods determining an appropriate performance grade of virgin binder, which is re(erred as design binder, in RAP contained bituminous mixture design process. However, difficulties have been experienced in utilizing the methods in the field application in Korea, because SHRP binder test, the key tests to determine a design binder, requires well-trained personnel, high price equipment, and time consuming process. Thus, the study investigated the relationship among the binder aging level, RAP contents, and rheologica1 properties of binder. The study results provide mix designer with a simple method in selecting an appropriate grade of virgin binder.
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◯R 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).
In this study, the tendency of flow characteristics according to the mixing design of mortar and mortar standard reference materials was analyzed based on the constituents of the standard reference materials for mortar. As a result, the plastic viscosity of the mortar tends to be maintained according to the amount of fine aggregate, while the yield value tends to increase greatly. On the other hand, in the case of the standard reference materials for mortar, the plastic viscosity tends to increase largely according to the amount of fine aggregate substitutes, while the yield value tends to be almost maintained.