Numerical models of composite floor systems with various thickness of phase change material and sizes of circular spacers were developed based on finite element analysis. In order to perform a heat transfer analysis, thermal properties of steels were determined and those of phase change material were estimated from experiment results. In addition, the thermal insulation performance of composite floor systems with respect to different thickness of phase change material and sizes of circular spacers was predicted. To verify the validity of analysis, analysis results were compared with vertical furnace fire test results of equivalent conditions. As a result, available thicknesses of phase change material and sizes of circular spacers were proposed to satisfy the thermal insulation criteria of Korean Standards.
This study aimed to provide volatile flavor compounds of three onion products through thermal process and alcohol fermentation, to meet the quality standard of onion products. The identified components of onion extracts (OE) included 49 (18 sulfur-containing compounds, 5 alcohols, 8 acids, 3 ketones, 4 esters, 4 aromatic compounds, 2 aldehydes, 1 pyrazines and 4 miscellaneous compounds), and 55 (17 sulfur-containing compounds, 15 alcohols, 5 acids, 11 ketones, 3 aromatic compounds, 2 aldehydes and 1 pyrazine) in autoclave-sterilized onion extracts (SOE); and 69 (10 sulfur-containing compounds, 27 alcohols, 11 acids, 11 ketones, 6 esters, 1 aromatic compound and 3 pyrazines) in onion wine (OW), respectively. Among the major flavor classes, sulfur-containing compounds (36.8%), acids (31.3%) and aldehydes (13.6%) in OE were changed to alcohols (46.5%) and ketones (27.3%) in SOE whereas, alcohols (56.3%) and acids (26.6%) in OW. Moreover, 1,3-butanediol, 2,3-butanediol, and 3-hydroxy-2-butanone were highly detected in SOE whereas, acetic acid, 3-methylbutanol, 2-phenylethanol and 1,2,3-propanetriol in OW.
The purpose of this study is to comprehend the change of the terms and the structure of the Pungpanbu in the T-shaped wooden shrines in the later Joseon period through the Salleung-dogamuigwes. Following conclusions have been reached through the study. First, the terms in the Salleung-dogamuigwes were similar to Yeonggeon-dogamuigwes but timing difference was verified. The word about the frame of Pungpanbu was different from the current. Second, in accordance with the extended of Pungpanbu, the members of frame of Pungpanbu had been increased and it had been changed to the lattice. The members of Pungpanbu used as plan dimensions and the size of the members had been gradually increased. Third, the Pungpanbu had been extended to protect the side of T-shaped wooden shrines. At the same time, the range of Chukjungbang had been extended. This was the result of the efforts of the era to reduce the range of plaster. This affected the overall elevation change of T-shaped wooden shrines.
Recently, there have been many efforts to establish suitable processes for recycling fly ash, which is produced in thermal power plants and which poses serious environmental problems. Use of fly ash as a major ingredient of ceramic tiles can increase fly ash utilization, as well as reduce the cost of raw materials in ceramic tile production. In this study, the effects of fly ash addition on ceramic tile properties such as bending strength, water absorption and porosity were investigated. A manufacturing process of ceramic tile was developed for utilization of fly ash with high carbon content. In this approach, it is important to hold the ceramic tiles at a temperature that is sufficient for carbon oxidation, before the pores supplying oxygen to the inside of the ceramic tile are sealed. Ceramic wall tiles were manufactured with 0-40wt% of fly ash addition. The water absorption and porosity of the fired body were slightly changed with increasing fly ash content up to 30wt% and decreased with greater amounts of fly ash addition. The bending strength of ceramic tile including 10wt% fly ash increased, reaching a level comparable to that of ceramic tile without fly ash.
본 연구에서는 식생 복원 유형별 토양동물의 변화를 알아보기 위해 비오톱이식공법, 산림표토포설, 소경목군락식재, 다층구조군락식재를 적용한 조사구와 이를 비교할 대조구를 선정하였다. 토양동물의 변화를 통한 토양동물자연도 분석 결과, 대조구는 환경에 민감한 동물군과 둔감한 동물군이 골고루 출현하고 있어 토양동물자연도가 높게 확인되었 다. 식재를 통해 복원된 조사구의 경우, 비오톱이식공법의 토양동물자연도가 대조구와 유사한 수준까지 도달해 있었으 며, 이보다 낮은 수준이긴 하나 소경목군락식재, 다층구조군락식재지역의 토양동물 또한 점진적으로 회복되고 있었다. 가장 낮은 토양동물자연도를 보인 조사구는 산림표토포설지역으로 확인되었다. 이를 통해 비오톱이식공법이 식재를 통해 복원된 조사구가 다른 조사구에 비해 토양동물의 회복이 좀 더 빨리 이루어지고 있음을 파악할 수 있었다. 이는 산림 내부의 숲을 그대로 굴취한 후 이식하는 것으로 표토와 심토의 일부분이 함께 옮겨지기 때문으로 판단
The feasibility of reduction of sodium intake using sun-dried salt and monosodium glutamate (MSG) was studied. Preference test was performed to evaluate the sensory properties of bean-sprout soup and vegetable rice porridge soup. Sun-dried salt and MSG might be a partial substitute for refined salt. There was a significant difference in salt taste strength between sun-dried salt and refined salt. Sun-dried salts 0.45% with MSG 0.07% resulted in the highest taste preference compared to that of sun-dried salts 0.60% without MSG in bean-sprout soup, which resulted in 23.9% reduction of sodium intake. Sun-dried salts 0.38% with MSG 0.04% resulted in the highest taste preference compared to sun-dried salts 0.53% without MSG in vegetable rice porridge soup, which resulted in 25.4% reduction of sodium intake. There seemed to be a synergistic effect on reduced usage of sodium salt when MSG was used in vegetable rice porridge and bean-sprout soup with sun-dried salt.
Module coordination(分數), which is crucially relevant to plan shape of a fortress and the location of its gates and chis(雉, protruding posts), have not been thoroughly studied, despite its importance in fortress system. While plan shape of Goryeo fortress features orderly placement of gates and chis, under medium-sized Joseon fortress doesn’t follow it strictly. As a result, fortresses with various plan shapes greatly outnumber those of Goryeo. Especially, Gimhaeeupseong Fortress, which is a large-scale town wall, shows such a complicated plan shape, making it difficult to figure out its modular coordination. Presumably, the reason for Joseon fortress’ complicated plan shapes, which doesn’t follow the orderly modular coordination, is thought to be in its various geographical conditions. Also, it seems that the building of fortress with such various and complicated plan shapes was to deter enemies from intruding by confusing them. And various plan shapes of fortress are also figured out to be pertinent to street system of towns and positions of public offices.
Quality changes of dried sea cucumber (Stichopusjaponicus) after applying a cyclic rehydration and retorting process were investigated during 4 weeks of storage. The length, volume, and weight of dried sea cucumber increased significantly as the number of rehydration cycles increased. Sea cucumber (SC) was bottled in the glass jar and a retort thermal process (121.1oC, 0.15 MPa) was applied. The total thermal processing time (TTT) was 24 min based on the temperature at the cold point. The size and texture of retorted SC were significantly changed until the first week of storage. However, regardless of the number of rehydration cycles, the size and texture of samples at different rehydration cycles showed no significant difference during the whole storage. The length, volume, weight, rehydration ratio (RR), hardness, and chewiness at the maximum degree of swelling during rehydration of dried SC were estimated as 100.86 mm, 38.62 mL, 41.05 g, 6.39 of RR, 249.19 gf, and 4.05 mJ, respectively.
Effect of salt concentration (10, 20 and 30%, respectively) and fermentation temperature (10 and 20oC, respectively) on changes in quality index (VBN, Histamine, Amino nitrogen, Total viable cell counts, Coliform bacteria and E. coli counts) of culinary salted and fermented anchovy during fermentation were investigated to suggestion of fundamental documents for industrial objectives. Our results show that the effect of salt concentration on changes in quality index was not high compared with fermentation temperature in salted and fermented anchovy with below 20% of salt concentration however effect of salt concentration and fermentation temperature on quality index was not significant with 30% salt concentration. And all most whole changes of quality index were rapidly increased or decreased for 30 days of fermentation.
Porphyromonas gingivalis is a gram-negative bacteria of rod shape, and grown in an anerobic condition. It colonizes in subgingival crevice and is known as a major pathogen causing chronic periodontitis. It possesses an invasive property and replicative potential within various cell types, presumably playing an important role in modulating biological behaviors of oral cancer. However, the pathophysiology of P. gingivalis in the malignant transformation of oral cancer has not been fully understood. In this study, we aimed to investigate molecular changes of oral squamous cell carcinoma cells induced by repetitive P. gingivalis infection that clinically resembles chronic periodontitis.
본 연구에서는 계절별 혼잡도 변화를 검토하기 위해 1년 동안의 주요 연안 통항로 및 항만 입출항로를 대상으로 계절별 기상특보가 발효되지 않은 1주일간의 GICOMS Data를 바탕으로 혼잡도 평가를 실시하였다. 그 결과 시간당 평균 혼잡도의 계절별 차이는 최대 약 11 %, 평균 약 3.5 %, 피크시간 혼잡도의 계절별 차이는 최대 약 82 %, 평균 약 30 %를 보이는 것으로 분석되었다. 향후 혼잡도 평가시에 이러한 계절별 혼잡도 변화를 감안하여야 하며, 특히 해상교통안전진단에서의 평가 시에는 이러한 계절별 차이가 존재하므로 혼잡여부에 대한 해상교통 안전대책 마련에 더욱 주의를 기울여야 할 것이다.
The purpose of this study is to identify the sensibility images when the direction and width of stripes change on semi-tight skirts. The researcher made 12 stimuli consisting of images of skirts with a combination of six stripe directions and two stripe widths. The images were assessed by 126 subjects who were students majoring in apparel. Three sensibility image factors were found: personality, attractiveness, and activity. Images of skirts with different stripe directions were perceived as having significant differences among these factors. Stripe widths of 1.5cm and 3cm in upward diagonal, vertical side line, and downward diagonal directions influenced the personality factor. Diagonal stripes with a width of 1.5cm positively influenced attractiveness and activity. Stripes in a vertical direction increased attractiveness when the stripe width was 1.5cm rather than 3cm. Although the interaction of stripe direction and width significantly influenced perceptions of attractiveness and activity in images of semi-tight skirts, they did not significantly influence personality. In accordance with the analysis, stripe direction was significantly different for all factors. This analysis indicated that each factor has its own independent influence. Stripe width had major independent effects, showing significance in attractiveness and activity. However, personality did not indicate any significant difference. The results of this study will help women select suitable clothing according to their individual preferences and body shapes by influencing how images are depicted because women will be able to use the images to estimate their body images when the skirts are put on.
경제ㆍ금융 관련 강의에 주식모의투자와 같은 실험적 게임기법에 대한 관심이 증가되고 있으며, 국내 여러 증권사에서는 주식 및 선물옵션 모의투자가 성행하고 있다. 그러나 이에 대한 금융교육 효과나 개인투자자의 의사결정에 미치는 효과 등에 대한 연구는 미흡한 수준이다. 본 연구에서는 먼저 실제 주식투자에 앞서 시행하는 모의투자 게임의 유효성과 금융교 육 효과에 대해 분석하였다. 또한 이러한 모의투자의 유효성 요인은 금융교육에 어떤 영향을 미치는지 그 결정요인에 대해 분석하였다.
궁극적으로는 주식모의투자의 효과를 분석하기 위해 개인의 리스크 선호도를 종속변수로, 주식모의투자의 유효성 요인 및 금융교육 효과 요인을 설명변수로 회귀분석을 실시하였다. 그 결과 주식모의투자의 유효성 요인으로서 투자의 기본지식 습득, 전문적 투자기법의 인식과 더불어 금융교육 효과 요인 중경제관심도가 리스크 선호도에 영향을 미치는 결정요인으로 밝혀졌다. 이는 곧 개인의 리스크 선호도는 리스크 프로파일을 결정하는 주요인으로서 주식모의투자 과정을 통해서 변화될 수 있음을 의미한다.
결론적으로 경제ㆍ금융교육에 있어서 전통적 강의기법보다는 주식모의투자와 같은 실험적 게임기법을 활용한 강의가 효과적인 측면이 있으나, 개인의 리스크 선호도를 변화시킬 수 있어서 이에 대한 주의 또한 요망된다 하겠다.
E (Electric) -glass fibers are the most widely used glass fibers, taking up 90 % of the long glass fiber market. However, very few papers have appeared on the physical characteristics of E-glass fibers and how they depend on the fiberizing temperature of fiber spinning. Glass fiber was fabricated via continuous spinning process using bulk E-glass. In order to fabricate the E-glass specimen, raw materials were put into a Pt crucible and melted at 1550 oC for 2hrs; mixture was then annealed at 621 ± 10 oC for 2hrs. The transmittance and adaptable temperature for spinning of the bulk marble glass were characterized using a UV-visible spectrometer and a viscometer. Continuous spinning was carried out using direct melting spinning equipment as a function of the fiberizing temperature in the range of 1175~1250 oC, while the winder speed was fixed at 500 rpm. Subsequently we investigated the physical properties of the E-glass fiber. The average diameter of the synthesized glass fiber was measured by optical microscope. The mechanical properties of the fiber were confirmed using a UTM (universal materials testing machine); the maximum tensile strength was measured and found to be 1843 ± 449MPa at 1225 oC.
This study investigates changes in the mechanical behaviors, especially hardness and indentation load-displacement curves, of thermal barrier coatings (TBCs) brought about by thermal shock. The TBCs on the Nickel-based bondcoat/superalloy was prepared with diameters of 25.4 mm and 600 μm thickness. The results of thermal shock cycling test from 1100 oC of the highest temperature indicate that the thermal shock do not influence on the mechanical behavior, but a continuous decrease in porosity and increase in hardness were observed after 1200 thermal shock cycles; these changes are believed to be due to sintering of thermal barrier coating materials. The results that no degradation in the indentation load-displacement curves indicate that the coating shows good thermal shock resistance up to 1200 cycles at 1100 oC in air.
This paper is concerned with a test method that can be used to investigate the parameters of the Johnson-Cook constitutive model. These parameters are essential for accurately analyzing material behavior under impact loading conditions in numerical simulation. Ti-6Al-4V alloy (HCP crytal structure) was used as a specimen for the experiments. In the 10−3-103/ s strain rate range, three types of experimental methods (convention, compression and tension) were employed to compare the differences using MTS-810, SHPB and SHTB. Finite element analysis results when applying these parameters were displayed along with the experiment results.
Zirconia nanoparticles were widely used as filler in order to get high refractive index layer. However, dispersion of nanoparticles is difficult due to their agglomeration in solvent. In this study, the dispersibility of the zirconia suspension is promoted by controlling the steric hindrance and electrostatic interactions through the adsorption of PEI according to alkali treatment time. Also, to induce improved dispersibility on suspension, we changed the dispersion conditions variously and fabricated an ink formulation method for the coating layer. Zirconia suspension was characterized by dynamic light scattering (DLS), Zeta potential measurement, Transmission Electron Microscope (TEM) and FT-IR. We were able to confirm that good dispersion of zirconia suspension by alkali treatment and PEI led to high refractive index.
암반생물막의 군집구조와 생물량의 시, 공간적인 변화를 확인하기 위하여, 파도에 대한 노출이 다른 고사포와 격포에 서 11월부터 2011년 9월까지 격월로 암반조각을 채집하였다. 군집구조는 채집된 암반조각을 칫솔로 긁어 광학현미경 하에서 미세조류의 분류군별 개체수를 계수하여 분석하였고, 생물량은 NDVI, VI, 엽록소 a 농도를 측정하여 확인하였 다. 고사포와 격포의 조간대 암반생물막에서 가장 우점하는 분류군은 Aphanotece spp., Lyngbya spp.를 포함하는 남조류 였으며, 환경스트레스가 적은 조간대 하부에서는 규조류의 출현율이 높게 나타났다. 암반생물막에서 우점하는 규조류는 Navicula spp., Achnanthes spp.와 Licmophora spp.로 확인되었다. 식생지수와 엽록소 a 농도는 격포에 비해 고사포 생물막에서 높게 나타났다. 식생지수인 NDVI와 VI는 고사포에서 각각 0.49-0.40(평균 0.43), 2.64-3.22(평균 2.90)였으 며, 격포의 암반생물막은 NDVI와 VI가 각각 0.32-0.41(평균 0.38), 2.03-2.86(평균 2.48)으로 확인되었다. 엽록소 a의 농도는 고사포에서 12.79-32.87 ㎍/㎠(평균 22.84 ㎍/㎠)였고, 격포에서는 11.14-18.25 ㎍/㎠(평균 15.48 ㎍/㎠)로 식생지수와 마찬가지로 1월(겨울)에 최대, 3월(봄)에 최소인 계절 변화를 보였다. 엽록소 a 농도는 NDVI, VI와 양의 상관관계를 보여 비파괴적인 식생지수 측정방법이 파괴적인 엽록소 a 추출 방법을 대체할 수 있음을 알려준다. 결론적으 로 암반생물막은 여름보다 겨울에, 조간대 상부보다 중부와 하부에서, 파도에 보호된 해안보다 노출된 해안에서 높은 값을 보였다.
대부분의 온실가스는 에너지의 생성 및 이용으로부터 발생되고, 교통부문에서 배출되는 온실가스 중 약 95 % 이상이 수송용 연료에서 기인한다. 또한, IPCC 가이드라인에서 제시하는 배출계수를 사용하였을 경우 국가 고유의 연료특성이 반영되지 않는 단점이 있고, 기후변화협약 교토의정서에 따른 의무 감축국도 UN에 제출하는 국가 온실가스 배출량 보고서 작성 시 대부분 Tier 2나 Tier 3 수준의 배출계수를 적용하고 있 다. 본 연구에서는 국내 교통부문에 사용되는 휘발유, 경유 등의 수송용 연료에 대한 연차별 시계열 특성을 파 악하고, CO2 배출계수의 연도별 변화추이를 분석하여 실제 연료를 활용한 CO2배출계수 실측방법의 적용 타 당성을 평가하였다.