• 청정기술
• /
• 제8권3호
• /
• pp.129-139
• /
• 2002

This is the study for recycling waste foundry sand. Authors studied about main subject of grading of aggregate and three experimental items such as physical properties of waste foundry sand, optimum grading for concrete products of low water ratio, and quality variations of concrete products according to substitution proportion of fine aggregate as waste foundry sand. We were convinced of following results by experimental study. The first was that waste foundry sand was not fit as the aggregate for concrete because of bad qualities such as grading, unit weight, solid volume and passing 0.08 mm seive, so it is proper to composition using with other fine aggregetes. The second was that optimum grading is fineness modulus of 2.77 to 3.28 And the last is that optimum condition about substitution proportion as waste foundry sand is 10% fine aggregate.

• 한국식품영양과학회지
• /
• 제33권8호
• /
• pp.1367-1372
• /
• 2004

보리의 도정과정중에 생성되는 도정부산물의 식품소재로서의 활용 방안으로 보리 도정 겨를 밀가루에 0∼30% 대체한 쿠키와 머핀을 제조하여 품질 특성을 조사하였다. 보리겨의 첨가는 쿠키의 퍼짐성, 밝기, 관능특성을 감소시키는 것으로 나타났다. 그러나 20% 첨가수준까지 보리 겨를 첨가하는 것은 쿠키의 top grain, 색, 풍미, 텍스쳐 그리고 전반적인 기호도에서 양호한 점수를 얻었으며 특히 10% 첨가수준에서는 관능특성에서 대조구와 유의적으로 큰 차이가 없는 것으로 나타났다. 머핀의 경우에도 보리 도정 겨의 첨가는 부피를 감소시키고 내부 기공의 특성이 떨어지는 결과를 초래하였지만 20% 첨가 수준 범위내에서 색, 풍미, 텍스쳐 등 머핀의 품질에 크게 부정적이지 않는 것으로 평가되었다.

• Journal of Animal Science and Technology
• /
• 제60권5호
• /
• pp.12.1-12.5
• /
• 2018

Background: The use of agroindustrial by-products in ruminant nutrition to be an interesting alternative in order to reduce production costs and environmental impacts arising from the inadequate destination of residues. The initial step of beer production yields a large volume of wet brewer's grains all year around, which is available at a low cost and has a high nutritional quality, and hence a big potential for animal production. Methods: Twenty-four Suffolk non-castrated male lambs, from simple parturition were kept in individual spots and allocated to four treatments constituted by four levels of substitution of sorghum silage by WBG (i.e.0; 33.5; 66.5 and 100% of substitution). It was used roughage: concentrate rate of 50:50, based on dry matter. Results: The ether extract intake increased while the acid detergent fiber intake decreased linearly ($P{\leq}0.05$). Substituion of sorghum silage by WBG did not change lambs' feed DMI, daily weight gain and feed conversion. Conclusion: The substitution of sorghum silage by WBG as roughage showed to be a viable alternative from the productive and economic point of view for finishing of feedlot lambs.

• 농업과학연구
• /
• 제47권3호
• /
• pp.533-544
• /
• 2020

In this paper, we conducted a dynamic ex-post assessment on the grape business cessation support System. Based on the analysis results, in the short term, there was an increase in grape price due to a decrease in production and accompanying increases in the prices of consumption substitution items. However, in the long run, grape prices fell again due to an increase in grape production because of the entry of new grape farmers and the growth of adult grape trees. In addition, the analysis showed that the balloon effect caused by the conversion of crops caused indirect damage such as an increase in the production volume of substitution crops and a decrease in prices. When analyzing the social welfare measurement, the results showed that the support system for business cessation increased the overall social welfare due to an increase in producer welfare because of a price increase in the short term, but in the long term, both producer and consumer welfare decreased. In the end, it is necessary to review the system because the government's intervention may cause market distortion and inefficient resource allocation. Above all, it is necessary to minimize the indirect effect of the industry's contraction and balloon effect due to excessive business cessation. For this, conditional support should be provided in parallel with post management rather than unconditional support. In addition, it is necessary to provide a strategic support system that considers substitution items in addition to those items to be supported.

• 한국재료학회지
• /
• 제33권11호
• /
• pp.465-474
• /
• 2023

The effects of La³⁺ substitution for Sr²⁺-site on the crystal structure and the dielectric properties of (Ba_0.7Sr_0.3-3x/2La_x) (Ti_0.9Zr_0.1)O₃ (BSLTZ) (0.005 ≤ x ≤ 0.02) ceramics were investigated. The structural characteristics of the BSLTZ ceramics were quantitatively evaluated using the Rietveld refinement method from X-ray diffraction (XRD) data. For the specimens sintered at 1,550 ℃ for 6 h, a single phase with a perovskite structure and homogeneous microstructure were observed for the entire range of compositions. With increasing La³⁺ substitution (x), the unit cell volume decreased because the ionic size of La³⁺ (1.36 Å) ions is smaller than that of Sr²⁺ (1.44 Å) ions. With increasing La³⁺ substitution (x), the tetragonal phase fraction increased due to the A-site cation size mismatch effect. Dielectric constant (ε_r) increased with the La³⁺ substitution (x) due to the increase in tetragonality (c/a) and the average B-site bond valence of the ABO₃ perovskite. The BSLTZ ceramics showed a higher dielectric loss due to the smaller grain size than that of (Ba_0.7Sr_0.3)(Ti_0.9Zr_0.1)O₃ ceramics. BSLTZ (x = 0.02) ceramics met the X7R specification proposed by the Electronic Industries Association (EIA).

• 한국식품영양과학회지
• /
• 제37권5호
• /
• pp.625-632
• /
• 2008

본 연구에서는 sourdough의 대체량을 20%, 40%, 60% 및 80%로 달리하여 제조한 호밀-밀 혼합빵의 품질 특성을 실험하였다. Sourdough의 pH와 총산도는 배양시간이 길어질수록 pH는 감소하는 경향을 나타내었고, 총산도는 증가하였다. 호밀-밀 혼합반죽의 sourdough 대체량이 증가할수록 pH는 감소하는 경향을 나타내었고, 총산도는 감소하는 경향을 나타내었다. 호밀-밀 혼합빵의 pH는 대조군보다 sourdough 대체군들이 유의적으로 낮게 나타났고, 총산도는 높게 나타났다. 발효팽창력은 발효시간이 길어질수록 유의적으로 증가하는 경향을 나타내었으며, sourdough 20% 대체군이 111.43%로 가장 높게 나타났다. 비용적은 sourdough 20% 대체군이 1.87 mL/g로 가장 높았다. 굽기 손실률은 sourdough 80% 대체군이 7.39%로 가장 낮았다. 수분활성도는 대조군이 0.919로 가장 높았고, 대조군보다 sourdough 대체군들이 유의적으로 낮게 나타났다. 명도, 적색도 및 황색도는 sourdough 대체군들이 대조군보다 유의적으로 높게 나타났다. 견고성, 점착성 및 씹힘성은 대조군이 가장 낮았고, 대조군보다 sourdough 대체군들이 유의적으로 높게 나타났다. 한편, 부착성은 대조군이 가장 높았고, sourdough 대체군들이 대조군보다 유의적으로 낮게 나타났다. 부서짐성, 응집성 및 복원성은 대조군과 sourdough 대체군들 간에는 유의적인 차이가 나타나지 않았다. 탄력성은 sourdough 20% 대체군이 0.746으로 가장 높았고, 40% 대체군이 0.629로 가장 낮았다. Sourdough 20% 대체군을 제외하고, 겉껍질과 로프의 양 옆면 사이에 브레이크(break)와 슈레드(shred)가 관찰되었다. 관능검사 결과에서 빵 속살의 색상, 기공의 균일성, 빵 속살의 경도, 입안에서의 점착성 및 전체적인 기호도는 sourdough 대체량이 증가할수록 유의적으로 감소하는 경향을 보였고, 호밀향과 쓴맛은 이와 반대의 경향을 보였다. 기공의 밀도, 탄력성 및 신맛은 대조군보다 sourdough 대체군들의 점수가 유의적으로 높게 나타났다. 이상의 결과를 종합해 보면, 대조군의 호밀-밀 혼합빵이 관능검사에서 가장 높은 점수를 나타냈고, sourdough 대체량이 많아질수록 관능검사 점수가 다소 떨어지기는 하였지만, 전체적인 품질특성을 고려해 보면 $20{\sim}60%$ 대체는 sourdough의 향과 맛을 지니면서도 상당히 우수한 빵제품을 생산해 낼 수 있을 것으로 사료된다.

• 한국식품영양과학회지
• /
• 제37권5호
• /
• pp.640-646
• /
• 2008

쌀겨와 발효쌀겨, 쌀겨유의 쇼트닝 대체에 따른 제빵특성 변화에 대하여 조사하였다. 빵 반죽에 대한 쌀겨의 첨가는 제빵 후 명도의 감소, 황색도 및 적색도의 증가와 전반적 물성 변화를 가져오나, 5% 정도의 쌀겨 첨가는 쌀겨의 기능성을 가지면서 대조구와 외관 및 물성적으로 큰 차이를 보이지 않았다. 효모로 예비 발효한 발효쌀겨의 첨가는 대조구와 큰 차이를 보이지 않으면서 texture 및 풍미가 향상되었다. 빵 반죽에 대한 쌀겨유의 쇼트닝 대체는 첨가 수준이 클수록 반죽 내 비 용적이 감소되었다. 황색의 쌀겨유의 첨가는 반죽의 명도를 낮추고 황색도를 증가시켰다. 또한 쇼트닝의 쌀겨유 대체는 경도, 씹힘성 그리고 부서짐 등의 증가를 가져오는 불리한 점이 있으나, 50% 정도의 쌀겨유 대체는 빵의 물성변화에 있어 대조구와 큰 차이를 나타내지 않았다. 또한 쌀겨유의 대체는 관능평가에서 부피의 상대적 감소 및 경도의 증가로 인한 질감의 저하를 가져오나, 제빵 후 풍미 향상을 유도하는 것으로 나타났다. 이상의 결과로 볼 때 쌀겨, 발효쌀겨 그리고 쌀겨유의 제빵과정 중 첨가는 빵의 색, 부피 등 외관상 대조구에 비하여 다소 변화를 가져올 수 있으나, 쌀겨 특히, 발효쌀겨의 첨가는 오히려 맛 과 풍미 향상을 가져오는 것으로 사료된다.

• 전기화학회지
• /
• 제7권3호
• /
• pp.131-137
• /
• 2004

Sol-gel method which provides better electrochemical and physiochemical properties compared to the solid-state method was used to synthesize the material of $LiFe_yMn_{2-y}O_4$. Fe was substituted to increase the structural stability so that the effects of the substitution amount and sintering temperature were analyzed. XRD was used for the structural analysis of produced material, which in turn, showed the same cubic spinel structure as $LiMn_2O_4$ despite the substitution of $Fe^{3+}$. During the synthesis of $LiFe_yMn_{2-y}O_4$, as the sintering temperature and the doping amount of Fe(y=0.05, 0.1, 0.2)were increased, grain growth proceeded which in turn, showed a high crystalline and a large grain size, certain morphology with narrow specific surface area and large pore volume distribution was observed. In order to examine the ability for the practical use of the battery, charge-discharge tests were undertaken. When the substitution amount of $Fe^{3+}\;into\;LiMn_2O_4$ increased, the initial discharge capacity showed a tendency to decrease within the region of $3.0\~4.2V$ but when charge-discharge processes were repeated, other capacity maintenance properties turned out to be outstanding. In addition, when the sintering temperature was $800\~850^{\circ}C$, the initial capacity was small but showed very stable cycle performance. According to EVS(electrochemical voltage spectroscopy) test, $LiFe_yMn_{2-y}O_4(y=0,\;0.05,\;0.1,\;0.2)$ showed two plateau region and the typical peaks of manganese spinel structure when the substitution amount of $Fe^{3+}$ increased, the peak value at about 4.15V during the charge-discharge process showed a tendency to decrease. From the previous results, the local distortion due to the biphase within the region near 4.15V during the lithium extraction gave a phase transition to a more suitable single phase. When the transition was derived, the discharge capacity decreased. However the cycle performance showed an outstanding result.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2015년도 추계 학술논문 발표대회
• /
• pp.55-56
• /
• 2015

In this research the processing method of Desulfurized Plaster is changed to cyclotomy, 0.3mm sieve analysis and 500℃ heat exposure, and by changing the mix rate of the binding agent to 0~20%, it was applied to mortar that used natural aggregate and blast furnace slag for testing. The test results showed that the sieve analysis and high heat exposure of the flow and air volume increased according to the increase of mixing rate of FGD while the cyclotomy decreased. The setting time accelerated as the mixing rate of FGD increased, and the compression strength increased to its maximum when the mixing rate of FGD was right around 10%, and especially showed a high trend with cyclotomy and sieve analysis.

• 한국지역사회생활과학회지
• /
• 제28권1호
• /
• pp.81-91
• /
• 2017

This study was carried out to investigate the quality characteristics and antioxidant activities of bread containing mistletoe (Viscum album var.) powder (at ratios of 0, 3, 5, 7, and 10% of total flour quantity). As mistletoe powder (MP) content increased, the pH levels of dough and bread and lightness decreased, whereas total titratable acidity increased. The fermentation power of the dough expansion by fermentation decreased with an increase in MP content added. Although bread weight decreased, there were no significant differences in baking loss as MP content increased. Volume and specific volume significantly decreased as MP content increased. Moisture content was highest at a substitution level of 10% and increased with increasing MP content. Lightness of crumbs significantly decreased with increasing MP content, whereas redness and yellowness showed the reverse effect. As MP content increased, changes in hardness, gumminess, and brittleness were all significant. In the sensory evaluation, color, flavor, softness, and overall acceptability were highest at MP 3% and were lowest at MP 10%. Total polyphenol contents and DPPH radical scavenging activity of bread significantly increased with increasing MP content. In conclusion, addition of MP 3% showed the best performance in terms of the nutritional and functional aspects of the bread.