The composite PAN fibers which incorporated with CNTs and Titania were prepared by mean of wet spinning. These fibers were then pre-oxidized with microwave heating in an air atmosphere. A combination of characterizations was carried out to study the impact of nanoparticles fillers on the properties of as-spun fibers and their performance during the microwave pre-oxidation. The addition of an equal amount of fillers made obvious changes in the chemical and crystalline structure, consequently improves the strength, and this could lower the capability to creep over a wide range of temperatures in the subsequent processes. FTIR and NMR analyses results of the pre-oxidized fibers exhibited clear changes in the PAN structure, where the dehydrogenation reaction and the degree of cyclization were investigated. Additional confirmation of the occurrence of cyclization reaction was achieved by XRD and thermal analysis. According to the TGA results, the pre-oxidized CNT1/ Ti-PAN fibers exhibit greater thermal stability suggesting high carbon content and good quality could result in the dependent carbon fibers.

교면 포장은 교통하중 및 온도 변화 등의 환경적 요인에 따라 상판, 거더, 신축/압축 이음 등의 교량 상부 구조물의 복잡한 거동을 나타나기 때문에 도로포장의 구조 성능과는 다르다. 이에 본 논문에서는 가변형 팬믹서를 활용하여 개질유황 합성 시멘트 콘크리트(MSCC)를 혼합하는 새로운 방법을 제시하고자 한다. 혼합 단계는 건식 및 습식의 두 단계로 이루어지며, 회전 모터의 속도의 변화를 주어 혼합하는 방식이다. 제안된 방법의 타당성을 평가하기 위해 실내 실험을 실시하였으며, 본 기술 적용 시 MSCC의 내구성이 향상되고 교량 포장 설계 요건을 충족하는 것을 확인하였다. 또한 내구성 및 경제성을 고려하여 최적 MSCC 개질유황 함량을 4%로 제안하고자 한다. 현재 제안된 기술의 적용 가능성을 확인하기 위한 추가적인 현장 평가가 수행되고 있으며, 가까운 시일 내에 결과를 제시할 예정이다.

Five-color bread was prepared by adding herb powder to Korean whole wheat triticum aestivum flour and the quality of baking was analyzed. The pH of the control bread was 6.15±0.12 while that of the whole wheat flour test group was 6.35±0.11, 6.29±0.12, 6.36±0.12, 6.19±0.11, and 6.01±0.13, respectively. The L value of the control bread was 67.78±0.03 and that of the whole wheat flour test group was 69.66±0.02, 60.01±0.12, 64.23±0.01, 63.34±0.01, and 61.64±0.04, respectively. The water activity was slightly increased at 2 days of storage due to the difference in water absorption and water retention. However, on the third day, the water transfer phenomenon in the bread showed water activity decrease in all wheat flour test groups. On the 1st day of the whole wheat flour test bread, the hardness values were 186.86±4.81, 165.89±3.73, 189.71±3.32, 198.38±2.19, and 184.29±3.40 g/cm2, respectively, and that of the control group was 138.84±3.72 g/cm2. The hardness of the control group and the whole wheat flour test group showed a significant difference. The internal structure of the bread in the whole wheat flour test group (100x, 500x) was not smoother than the control’s. The swelling degree of the starch particles and the cracking of the crumbs were confirmed by the adding of five-colored herbs to whole wheat flour.

Commercial ultra-high-strength PAN-based carbon fibers (T1000G) were heat-treated at the temperature range of 2300– 2600 °C under a constant stretching of 600 cN. After continuous high-temperature graphitization treatment, microstructures, mechanical properties and thermal stability of the carbon fibers were investigated. The results show that the T1000G carbon fibers present the similar round shape with a smooth surface before and after graphitization, indicating the carbon fibers are fabricated by dry–wet spinning. In comparison, the commercial high-strength and high-modulus PAN-based carbon fibers (M40JB and M55JB) present elliptical shapes with ridges and grooves on the surface, indicating the carbon fibers are fabricated by wet spinning. After graphitization treatment from 2300 to 2600 °C under a constant stretching of 600 cN, the Young’s modulus of the T1000G carbon fibers increases from about 436 to 484 GPa, and their tensile strength decreases from about 5.26 to 4.45 GPa. The increase in Young’s modulus of the graphitized T1000G carbon fibers is attributed to the increase in the crystallite sizes and the preferred orientation of graphite crystallites along the fiber longitudinal direction under a constant stretching condition. In comparison with the M40JB and the M55JB carbon fibers, the graphitized T1000G carbon fibers are easier to be oxidized, which can be contributed to the formation of more micropores and defects during the graphitization process, thus leading to the decrease in the tensile strength.

In the Anzunbaengi (Triticum aestivum) whole wheat flour mixture group, some herbs (A [white], B [yellow], C [black], D [blue], and E [red]) were added. The physicochemical properties were compared to the strong flour and whole wheat flour mixture groups. The dry gluten content of the control group (strong flour) was 13.5±0.4%, and the content in the whole wheat flour test group was slightly lower in value than the control group. The final viscosity, breakdown, and setback values of the dough were 248.4±0.8, 104.8±0.9, and 103.1±2.9 RVU, respectively. The breakdown was significantly different in the control and whole wheat flour groups. The setback value of the dough was increased by 30 RVU in the whole wheat flour test group compared to the control group by 103.1±2.9 RVU, but there was no significant difference between the test group samples. The consistency of the control dough was 500±10 FU, and the whole wheat flour test group was significantly increased to 585±10~599±10 FU, respectively. The absorption rate was about 2% higher in the whole flour test group than in the control group (66.2±0.3%). The pH of the control paste gradually decreased with fermentation time, and the results of whole wheat flour test group were similar (5.78±0.12~5.88±0.12). As the fermentation time increased, the volume of dough was increased and the result was slightly lower in the whole wheat flour test group than in the control group.

본 연구에서는 녹말(starch)과 poly(acrylonitrile) (PAN)으로 이루어진 가지형 공중합체 기반의 슈퍼 캐퍼시터용 전해질막을 손쉽게 제조하는 방법을 제시하였다. 가지형 공중합체(starch-g-PAN)는 세륨 이온에 의해 개시된 자유 라디칼 중합을 통해 합성되었다. 실온에서 어떠한 유기용매 없이 Starch-g-PAN 고분자를 이온성 액체, 1-ethyl-3-methylimidazolium dicyanamide (EMIM DCA)에 용해하였으며 1시간 동안 100°C의 고온을 가해줌으로써 손쉽게 고분자 막을 만들었다. 제조된 막은 유연하여 플렉서블 고체 슈퍼 캐퍼시터의 전해질에 적용되었다. Starch-g-PAN 기반의 고분자 전해질막을 사용한 슈퍼 캐퍼시터는 0.5 A/g의 전류 밀도에서 약 21 F/g의 정전용량을 가졌으며 10,000 사이클 동안 86%의 유지율을 보이며 높은 주기 안정성을 보였다. 본 연구를 통해 starch-g-PAN 기반의 고분자 전해질막이 우수한 성능을 가진 플렉서블 고체 슈퍼 캐퍼시터에 응용될 수 있음을 확인하였다.

This study was conducted to evaluate the characteristics of bread and the rheology of flour dough containing jochung. In the farinogram test, the addition of jochung changed water absorption, development time and mixing tolerance index for making bread As the amount of jochung increased, the water absorption, mixing tolerance index decreased and the development time increased. In the extensograph test, the degree of extension decreased with increasing of jochung content whereas degree of resistance was enhanced with addition of jochung. After fermentation treatment, the volume of the dough with 20% sucrose were less than that of the dough containing 20% of jochung. The dough with 5% jochung showed the lowest dough raising power compared to the other doughs. The bread consisting of 15% jochung showed the highest volume of loaf and specific volume. Therefore, high quality of bread can be achieved by adding jochung instead of sucrose for making bread.

In the modern industrial period, the introduction of mass production was most important progress in civilization. Die-casting process is one of main methods for mass production in the modern industry. The aluminum die-casting in the mold filling process is very complicated where flow momentum is the high velocity of the liquid metal. Actually, it is almost impossible in complex parts exactly to figure the mold filling performance out with the experimental knowledge. The aluminum die-castings are important processes in the automotive industry to produce the lightweight automobile bodies. Due to this condition, the simulation is going to be more critical role in the design procedure. Simulation can give the best solution of a casting system and also enhance the casting quality. The cost and time savings of the casting layout design are the most advantage of Computer Aided Engineering (CAE).. Generally, the relations of casting conditions such as injection system, gate system, and cooling system should be considered when designing the casting layout. Due to the various relative matters of the above conditions, product defects such as defect extent and location are significantly difference. In this research by using the simulation software (AnyCasting), CAE simulation was conducted with three layout designs to find out the best alternative for the casting layout design of an automotive Oil Pan_BJ3E. In order to apply the simulation results into the production die-casting mold, they were analyzed and compared carefully. Internal porosities which are caused by air entrapments during the filling process were predicted and also the results of three models were compared with the modifications of the gate system and overflows. Internal porosities which are occurred during the solidification process are predicted with the solidification analysis. And also the results of the modified gate system are compared.

정조(正祖, 재위 1776-1800)시대를 대표하는 국중(國中) 최고의 화가였던 김홍도 (金弘道, 1745-1806년 이후)는 문인 수준의 지적 소양까지 겸비했던 인물이다. 그러나 양반이 아니면 사회적 대우를 거의 받지 못했던 신분제 사회의 질곡은 김홍도 또한 넘기 힘든 벽이었다. 본고에서 필자는 사농공상(士農工商)의 위계질서를 바탕으로 형성 된 엄격한 신분제 사회라는 한계 속에서 김홍도가 느꼈을 비애와 자기 연민을 중심으로 이러한 그의 신분 의식이 어떻게 그의 작품 속에 드러나 있는가를 살펴보고자 하였다. 신분제적 모순에서 김홍도가 느낀 소외감과 불만을 유추해보는데 가장 중요한 작품은 고려대학교박물관 소장의 <송하취생도(松下吹笙圖)>이다. 이 그림에서 흥미로운 부분은 그림 오른쪽에 적혀있는 김홍도의 제발로 그 내용은 “생황의 [길고 짧은] 들쑥날쑥한 모습은 봉황의 날갯짓 같고 월당(月堂)에 울려 퍼지는 생황 소리는 용(龍)의 울음보다 처절하네(筠管參差排鳳翅, 月堂凄切勝龍吟)”이다. 김홍도가 느낀 신분제적 차별과 관련해서 주목되는 것은 “용의 울음(龍吟)”이다. 중인 출신의 시인이었던 이득원(李得元, 1639-1682)은 한 시에서 “용처럼 으르렁거리고(龍吼) 빈산의 귀신처럼 울부짖는 칼”로 신분제적 차별 속에서 고통받았던 자신을 비유하였다. 그런데 이 제발에서 김홍도는 용의 울음보다도 더 처절한 생황 소리를 자신의 울분과 고뇌를 표현하는 상징으로 활용하였다. <단원도(檀園圖)>(1784년, 개인 소장)는 김홍도가 1781년에 자신의 집에서 강희언(姜熙彦, 1738-?), 정란(鄭瀾, 1725-?)과 같이 가진 모임을 그린 그림이다. 이 그림의 제발에서 김홍도는 이 모임을 ‘진솔회(眞率會)’로 지칭하였다. 그런데 이 진솔회는 북송시대를 대표하는 문인이었던 사마광(司馬光, 1019-1086)의 아회였던 ‘진솔회(眞率 會)’를 모델로 한 것이었다. 김홍도가 자신의 모임을 사마광의 진솔회에 비유한 것은 그가 스스로에 대해 매우 강한 자부심을 가지고 있었음을 보여준다. 김홍도는 당시(唐詩), 송시(宋詩)에 대한 이해가 깊었으며 다수의 시의도(詩意圖)도 제작하였다. 김홍도는 문 인적 소양을 갖춘 화가로 높은 자존 의식을 지니고 있었다. 그러나 엄격한 신분제 사회에서 김홍도는 뛰어난 재주와 능력을 지니고 있었지만 그 뜻을 펼칠 수 없었다. 중인으로서 그가 느낀 슬픔과 좌절감은 그의 그림 속에 녹아있다. 정조시대를 대표하는 최고의 도화서 화가였던 그의 화려한 명성 뒤에 숨어있었던 그의 신분 의식을 고려하지 않는 한 우리의 김홍도에 대한 이해는 절반에 불과할 수밖에 없다.

본 연구에서는 고분자인 polyacrylonitrile (PAN) 고분자에 산화 그래핀(Graphene Oxide, GO)을 첨가하여 전기방사법을 통해 나노섬유 복합막(GO-PAN)을 제조하였으며, 과량의 GO를 첨가하기 위해 표면개질 전략을 사용하였다. 계면활성제를 사용하여 GO의 표면을 간단히 변형하면 GO의 안정성 및 분산도 증가로 인해 최종적으로 분리막에 필러의 함량을 3wt%까지 증가시켰다. 이렇게 변형된 GO(mGO)의 PAN 나노섬유막으로의 도입은 원래의 PAN 나노섬유막과 GO-PAN 막에 비해 향상된 친수성과 기계적 강도를 가진다. 따라서 나노필러의 표면 개질은 최종 복합막의 성능에 영향을 미치며 이는 GO의 분산도와 상관관계가 있는 것으로 보인다.

기존의 교면 포장이나 측구 시공에 적용한 건설재료들의 성능저하로 인해 유지보수비가 증가하고 있는 추세이다. 이에 본 연구에서는 현장 실험을 통해 개질유황 콘크리트의 내구성을 평가하는데 있어 기존의 고정형 팬믹서와 건 비빔 시 자전속도 변환이 가능한 가변형 팬믹서를 이용하여 내구성 평가 시험으로 콘크리트의 압축강도 시험을 수 행하였다.

This study was conducted to evaluate characteristics of bread and rheology of flour dough containing fructooligosaccharide. In the farinogram test, addition of fructooligosaccharide changed stability and development time. Stability and development time increased as the amount of fructooligosaccharide increased. In the extensograph test, the degree of extension decreased with increasing of fructooligosaccharide content, whereas degree of resistance increased. The volume of the loaf bread containing 10% fructooligosaccharide was the largest, and the bread containing 15% fructooligosaccharide revealed the best taste, flavor, and texture scores. After fermentation treatment, the volume of the dough with 20% of sucrose were less than that of 20% of fructooligosaccharide. Dough with 20% of sucrose revealed lowest dough raising power compared to other doughs. Overall, preference scores by sensory evaluation of bread containing fructooligosaccharide were higher than that of bread with sucrose. Therefore, excellent quality of bread may be achieved by adding fructooligosaccharide instead of sucrose to the process.

이 논문은 금병매의 여주인공인 반금련의 욕망분석과 그녀의 삶이 비극으로 치닫게 된 원인 연구를 주제로 한다. 금병매는 명 중엽 이후의 심학 사상의 영향으로 인해 욕망을 긍정하던 사회적 분위기 속에서 나온 소설이다. 그에 걸맞게 금병매 속의 모든 인물들은 각자의 개성을 드러내고 있으며 원초적이고도 다양한 욕망들을 사실적으로 드러내고 있다. 그 중에서 도 반금련은 여성이라는 사회적 약자의 지위에 있으면서도 삶에 순응하거나 외부적 제약을 받아들이기 보다는 적극적으로 삶을 개척하고자 하였고 자신의 욕망을 만족시키기 위해 수단과 방법을 가리지 않고 노력하였다. 본고에서는 반금련이라는 인물이 적나라하게 드러내고 있는 여러 욕망의 대상, 욕망 추구의 양상 등을 살펴보고 그녀가 맞이하게 되는 비극의 원인 을 개인적·사회적·사상적 배경 속에서 살펴보았다.

Graphite fibers are materials with a high specific modulus that have attracted much interest in the aerospace industry, but their high manufacturing cost and low yield are still problems that prevent their wide applications in practice. This paper presents a laser-based process for graphitization of carbon fiber (CF) and explores the effect of laser radiation on the microstructure of CF. The obtained Raman spectra indicate that the outer surface of CF evolves from turbostratic structures into a three-dimensional ordered state after being irradiated by a laser. The X-ray diffraction data revealed that the growth of crystallite was parallel to the fiber axis, and the interlayer spacing d002 decreased from 0.353 to 0.345 nm. The results of scanning electron microscopy revealed that the surface of irradiated CFs was rougher than that of the unirradiated ones and there were scale-like small fragments that had peeled off from the fibers. The tensile modulus increased by 17.51% and the Weibull average tensile strength decreased by 30.53% after being irradiated by a laser. These results demonstrate that the laser irradiation was able to increase the graphitization degree of the CFs, which showed some properties comparable to graphite fibers.

This study was carried out to investigate the characteristics of the quality of bread containing Red Ginseng Jung Kwa by-product, added in ratios of 0, 10, 20 and 30% of flour. It was found in dough and bread containing red ginseng Jung Kwa by-product that dough and loaf volume, specific loaf volume, baking loss, and pH decreased with an increasing amount of red ginseng Jung Kwa by-product. In addition, loaf weight and hardness were also reduced. In particular, hardness appeared to be 2.18 times higher for bread containing 30% Red Ginseng Jung Kwa by-product as compared to the amounts found in the control. For color, increasing the amount of Red Ginseng Jung Kwa by-product reduced the L value, whereas the a and b values were increased. In the sensory evaluation, the highest overall preference score was observed in the bread containing 20% red ginseng Jung Kwa by-product, whereas the lowest score was found in the control (no red ginseng Jung Kwa by-product added). It was concluded that pan bread containing red ginseng Jung Kwa by-product could be prepared with good acceptability, and that its optimum concentrate was found to be 20% of flour.

본 연구에서는 graphene oxide (GO)를 polyacrylonitrile (PAN)에 첨가하여 전기방사법을 이용해 나노섬유 복합막 을 제조한 뒤 물리적 특성을 관찰하였다. GO의 제조는 개선된 Hummer’s 방법을 이용하였으며, 표면처리가 되지 않은 GO의 경우 0.5 wt% 이상에서 전기방사가 이루어지지 않았다. GO의 안정성 및 분산도 증가를 개선하기 위해 계면활성제를 이용하 여 GO의 표면처리를 하였다. 표면처리가 된 GO를 사용하여 나노섬유 복합막의 GO의 함량을 0.5 wt% 이상 첨가할 수 있었 다. 특히, 표면처리가 된 GO가 첨가된 나노섬유 복합막은 향상된 물리적 특성을 가지며, 이는 나노섬유 분리막 내의 GO의 분산도와 상관관계가 있는 것으로 보인다.