이 연구는 셀룰로오스 또는 실리카를 포함하고 있는 목재, 왕겨 및 축분 바이오차로 시멘트 또는 잔골재를 대체한 콘크리트 의 강도시험을 통하여 역학적 특성을 파악한 것이다. 시험결과에 따르면, 바이오차 종류에 따른 강도는 왕겨 바이오차 혼입 콘크리트가 가장 크고, 다음으로 목재 바이오차였으며, 축분 바이오차가 가장 낮은 것으로 나타났다. 그리고 시멘트 또는 잔골재의 대체율에 따른 콘크리트 강도는 왕겨 바이오차의 대체율이 증가할수록 강도가 감소하였으나, 목재 및 축분 바이오차의 경우에는 대체율에 따라 강도 가 증가 하였다. 또한, 바이오차를 혼입하지 않은 보통 콘크리트와 비교하여 왕겨, 목재 및 축분 바이오차 순으로 최대 강도가 90%에 서 99%까지였으며, 압축강도로 추정하는 휨강도 또는 쪼갬인장강도 또한 보통 콘크리트의 상관 계수와 비슷하였다. 이와 같은 시험결 과를 근거로, 바이오차를 혼합한 콘크리트의 역학적 특성은 대체율에 따른 차이에도 불구하고 보통 콘크리트와 비슷한 강도를 확보할 수 있으므로 바이오차를 콘크리트의 새로운 혼화재료로 사용할 수 있을 것으로 판단된다.

세계적으로 환경에 대한 관심이 커지면서, 탄소 저감 및 탄소 중립을 위한 다양한 연구들이 진행되고 있다. 특히 최 근에는 탄소 포집 및 저장 기술인 CCS(Carbon Capture and Storage)에 주목이 높아졌다. 그뿐만 아니라, 대기 중의 탄소를 효과 적으로 저장하는 특성을 가진 바이오차는 탄소 중립에 기여할 수 있는 방안으로 다양한 연구가 진행되고 있다. 건설 산업에서 는 시멘트 대체재를 활용한 탄소 감소 관련 연구가 진행 중이며, 본 연구에서는 바이오차를 콘크리트 및 모르타르의 시멘트 대 체재로 활용하여 시멘트 사용량을 줄이고, 동시에 콘크리트 및 모르타르 내의 탄소를 포집하고 저장하여 탄소 배출량을 감소시 키고자 한다. 이를 위해 바이오차의 시멘트 치환율을 0%, 10%, 20%로 설정하고, 각각의 경우에 대해 콘크리트 및 모르타르의 슬럼프, pH 농도, 그리고 압축강도를 비교하였다.실험 결과에 따르면, 바이오차의 시멘트 치환율이 증가함에 따라 슬럼프와 압 축강도가 감소하는 경향을 보였으며, pH는 유사한 양상을 나타냈다.

In this study, the quality characteristics were compared by substituting allulose with a ratio of 0-40% instead of sugar used in dacquoise. The specific gravity and pH of the dacquoise dough were not significantly different, regardless of the allulose content. The spreadability was the highest in the sample using only sugar and decreased as the allulose content increased. Moisture content did not show a significant difference, the baking loss was the highest in the sample using 100% sugar, and there was no significant difference in the samples replaced with allulose. As a result of measuring the chromaticity of dacquoise, the L value and b value decreased and the a value showed a significant difference between the samples as the amount of substitution of allulose increased. Hardness increased as the replacement amount of allulose increased, while gumminess and chewiness showed similar trends. As a result of the sensory evaluation, the overall acceptability for the substitute sample of 100% sugar and 10% allulose was the highest. The maximum substitution ratio of allulose for dacquoise is considered to be 10%.

In this study, the quality properties were compared by replacing allulose with a ratio of 0%-100% instead of sugar used in sponge cake. There was no significant difference in specific gravity, pH, and degree Brix of the dough according to the allulose content, but the brightness decreased and the redness, and yellowness increased as the allulose content increased. The volume of the sponge cake decreased as the content of allulose increased. Symmetry was uniform in the cakes replaced with allulose compared to 100% sugar. There was no significant difference in baking loss and moisture content. Hardness, gumminess and chewiness increased as the replacement rate of allulose increased, and adhesiveness was highest in 100% allulose. In the hedonic evaluation, 100% sugar and allulose 25% samples showed no difference, and the other samples were evaluated lower than the control. The maximum replacement ratio of allulose for sponge cake is considered to be 50%.

본 연구에서는 설탕 대체 비율에 따른 알룰로스의 이화학적 특성 변화를 연구하였다. 알룰로스의 설탕 대체비율을 0, 25, 50, 75, 100%로 설정한 후 수분함량, pH, Brix 의 변화를 측정하였다. 설탕 100%를 사용하였을 경우 0.11%로 가장 낮은 수분함량을 나타냈으며, 알룰로스의 함량이 높아질수록 수분함량이 증가하는 경향을 보였다. pH 는 설탕 100%와 알룰로스 100%를 제외하고 알룰로스 대체에 따른 시료간의 유의적 차이는 없었으며, brix는 알룰 로스의 함량이 높아질수록 낮은 값을 보였다. 상대습도에 따른 흡습량의 정도를 측정한 결과, 모든 실험조건에서 알룰로스 함량이 높아질수록 흡습량이 높아졌으며, 상대습도가 높을수록 흡습량의 증가가 더 큰 것으로 나타났다. 상대습도가 높고 알룰로스의 함량이 높을수록 흡습이 일어나 는 기간이 긴 것으로 나타났다. 이러한 알룰로스와 설탕의 혼합 비율에 따른 수분함량 및 흡습량의 자료는 앞으로 제빵 공정에 있어서 최종제품의 품질을 결정할 수 있는 기초자료로서 활용이 가능할 것으로 판단된다.

본 연구는 국내 실정에 맞는 적정 TDN/CP 비율을 결정하기 위하여 4.6:1(T1)과 4.3:1(T2)의 비율로 생후 13개월령 육성우에게 급여하여 영양소 섭취량, 소화율, 반추 위액 특성 및 혈액조성에 대하여 조 사하였다. 건물 섭취량은 9.0kg/day로 동일하였으며, 조단백질 섭취량은 T1이 1.34kg/day, T2가 1.45kg/day로 T2가 조금 높았으나 유의적인 차이는 없었다. 섬유소 섭취량과 소화율은 T1이 조금 높은 경향을 보였으나 유의적인 차이는 없었다. 사료 섭취 후 4시간째 위액의 pH, ammonia-N, VFA 농도 를 비교한 결과 처리구간 유의적인 차이를 나타내지 않았다. 전반적인 VFA 수치는 TDN/CP 비율에 따 라 큰 영향이 없었으나 T1 처리구에서 iso-butyrate, iso-valerate 및 A/P ratio가 유의적으로 높은 결과를 보였다(p<0.05). 혈액 특성에는 처리구간 유의적인 차이를 나타내지 않았다. TDN/CP 비율이 4.3:1과 4.6:1 수준은 반추위 특성에 큰 영향을 미치지 않았지만, 소화율과 비교하였을 때 생후 13개월 령 육성우 시기에는 섬유소 섭취량과 소화율이 증가되는 4.6:1 수준이 보다 적합할 것으로 판단된다.

The optimization of brown rice replacement ratio and superheated steam (SHS) treatment conditions in production of extruded rice snack for infants were conducted using a response surface methodology. Experiments were designed using a Box-Behnken design with three independent variables (brown rice replacement ratio, SHS temperature, and SHS time) and two response variables (hardness and water uptake). The second order polynomial model showed a satisfactory description of the experimental results. Optimal conditions for extruded snack with the lowest predicted hardness (2.84 kg/cm2) were 15.81% of brown rice replacement with SHS treatment at 279.59oC for 197.40 sec. Meanwhile, optimal conditions for extruded snack with the highest predicted water uptake (384.79%) were 17.18% of brown rice replacement ratio with SHS treatment at 274.52oC for 196.22 sec.

In this paper, an evaluation of a product replacement ratio of irreparable items to the normally working ones is performed with a view to a warranty analysis. It is demonstrated that the replacement ratio during the warranty period can be estimated from t

급속공사 현장에 사용되는 속경성 보수모르타르의 내구성능 증진을 위해 사용재료의 물리적 성능을 평가하였다. 이를 위해 염화물 확산 억제 성능을 보유한 페로니켈 수쇄슬래그 잔골재와 급결제, EVA계 폴리머를 모르타르에 치환시켜 급결성능과 기초적 성능을 평가하였다. 그 결과 FNS잔골재 및 RS잔골재 사용에 따른 압축강도, 휨강도, 부착강도가 증가되었다. 속경성 폴리머 모르타르의 염화물 이온 촉진시험의 결과 FNS를 50%이하 사용 시 재령 7일에서 재령 28일간 염화물 억제 성능이 유지되었으며, FNS잔골재 및 RS잔골재 사용에 따른 내구성 저하는 발견되지 않았으나, 건축 및 토목용 대체골재로 사용하는데 경제성 및 장기 내구성에 대한 추가 검토가 필요할 것으로 판단된다.

In this study, the mechanical properties of concrete incorporating blast furnace slag with 60 % were analyzed according to CBS-Dust replacement rate. Results indicate that replacement of more than 10 % of CBS-Dust have a positive effect on reducing waste disposal costs and strength improvement

This study evaluated the fluidity and compressive strength of concrete by replacement ratio of blast furnace slag fine aggregate and ferronickel slag fine aggregate to investigate the possibility of replacing natural fine aggregate with steel slag for fine aggregate. Test results show that the use of steel slag fine aggregate improves the fluidity of concrete and compressive strength of concrete was higher than plain concrete.

In this study, the gamma-ray shielding characteristics of mortar specimens substituted CRT waste glass as a fine aggregate were evaluated. According to the results, the linear attenuation coefficient of mortar specimen replaced with CRT waste glass was increased. Especially, the half-value layer of CRT waste glass specimen in radiation source of 122KeV·57Co was 48% higher than that of normal sand specimen.

This research and development analysis provides numerical analysis techniques that can be used conveniently to determining the safety of the current state and to predict the stability in the future. It also seeks to present algorithms of back analysis to develop unified management system for control, prediction, coordination, and information modeling that can reasonably handle appropriate responses to structural behavior at project sites and design changes.

In this paper, the mechanical properties of GGBFS concrete according to the replacement ratio of electric arc furnace oxidizing slag fine aggregate was evaluated. As the replacement rate of EOS fine aggregate increased, the amount of slump and air content decreased. In addition, EOS concrete increased the initial compressive strength, but, it tended to decrease at 28 days.

Waste concrete powder generated during the process of recycling waste concrete into aggregate has a low recycling rate. This is because fine particles of waste concrete powder and cement components are present. Therefore, in this study, waste concrete powder is used as a raw material for centrifugal concrete. Experimental results show that waste concrete powder has cement and aggregate composition, SEM image has irregular shape, C-S-H and Ettringite exist inside. Waste concrete powder showed the same strength, up to 5% in terms of strength by age according to the substitution rate. Also, as the strength characteristics varied according to the centrifugal forming force, the substitution rate of siliceous matter increased by 5% and the strength decreased by substitution rate of 5%. Because of this study, it is considered difficult to use waste concrete powder as a substitute for silica sand because of the resulting characteristics of centrifugal concrete. It is recommended that economic and environmental concerns be considered when some substitution is made for silica sand.

The amount of ferro-nickel slag powder produced by the Fe-Ni industry has grown in conjunction with the increase in demand for stainless steel materials. In this study, we investigated the effects of ferro-nickel slag powder on the flow, strength, and microstructure of polymer mortar. Ferro-nickel slag powder was used to replace CaCO3 at ratios of 0%, 25%, 50%, 75%, and 100% by volume. The flow and the compressive and flexural strength of the polymer mortar were measured, and both scanning electron microscopy (SEM) and hot resistance testing were performed. The test results indicate that the flow of the polymer mortar with more than 25% CaCO3 replacement decreased as the ferro-nickel slag powder content increased. The compressive strength of the polymer mortar mixes with ferro-nickel slag powder was relatively higher than that of the control mix. From the results of the hot resistance test, the strength improved compared with that before the test and increased as the powder replacement ratio was increased.

This study investigated the properties of lightweight foamed concrete by using surfactant and synthetic foaming agent, lightweight aggregate. The effects of foaming agent types and replacing ratio of lightweight aggregate on the compressive strength, density and pore structure of the concrete were investigated. This study showed the improvement of important properties of lightweight foamed concrete. Lower pore distribution and correspondingly higher compressive strength values were reached. Also, synthetic foaming agent had more positive effect on the strength of foamed concrete.

This study was conducted examine the mechanical properties of LEFC in relation to the type of light weight aggregate and replacement ratio. For the specimen, different replacement ratio was used for recycled waste ALC and the bottom ash light weight aggregate respectively. The tests revealed that 60% of the waste ALC light weight aggregate is suitable for securing the optimal strength and light weight of the LEFC.