• 한국건축시공학회지
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• 제19권2호
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• pp.113-121
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• 2019

SWCNT는 매우 뛰어난 역학적 성능을 가지고 있고. 이로 인해 각종 첨단 소재의 보강재료로서 각광받고 있다. 그러나 완전한 형태의 SWCNT는 소수성을 가지고 있고. 서로간에 Van der Waals 인력으로 결합되어 물에 분산이 어렵다. 본 연구에서는 SWCNT를 시멘트 복합체에 활용하기 위하여, 분산된 용액 형태로 제조하여 시멘트 복합체에 활용하고자 하였고, 이를 위한 계면활성제로 DOC 및 SDS를 선정하였다. 초음파 처리 및 초원심분리를 통해 제조된 SWCNT 수용액을 이용하여 시멘트 페이스트를 제조하여 이의 전단응력 vs. 전단변형률 관계를 확인하고, 이를 통해 소성점도 및 항복응력을 도출하였다. 본 연구의 결과에 따르면 SWCNT를 혼입하지 않은 DOC 및 SDS는 공기연행제와 유사한 유변학적 효과를 발휘하는 것으로 나타났다. DOC 2wt%를 이용해서 제조된 SWCNT 수용액으로 배합된 시멘트 페이스트는 플레인 시멘트 페이스트와 거의 유사한 유변학적 거동을 하는 것으로 나타났으나, SDS 1%를 이용해서 제조된 SWCNT 수용액으로 배합된 시멘트 페이스트는 플레인 시멘트 페이스트와 상이한 유변학적 거동을 하는 것으로 나타났다.

• 대한토목학회논문집
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• 제28권6C호
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• pp.321-329
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• 2008

본 연구에서는 전통적인 압밀촉진공법의 단점을 보완하기 위한 방법으로 석션보드드레인 공법을 제안하고, 본 공법의 개량특성을 파악하기 위해, 배수재 종류 및 단계 진공압 조건에 따른 일련의 Column 실험을 실시하였다. 이때 실험 간 발생되는 침하량과 실험 종료 후 발생된 함수비 저감효과 및 강도증진효과를 파악하고, 개량 기간에 따른 압밀도를 파악하여 각 조건에 따른 최적의 석션보드드레인 공법 영향인자를 산정하고자 하였다. 각 배수재(포켓식 성곽형, 코일형, 하모니카 형, 원형 및 열융착식 성곽형배수재) 종류에 따른 개량 효과를 파악하기 위한 실험 결과, Core 형상(원형, 판형)과 필터의 Core 부착 여부(포켓식, 열융착식)에 의해 열융착식 성곽형 배수재와 포켓식 원형배수재의 배수효율이 다른 배수재의 경우 보다 좋게 나타났다. 단계석션압 조건 실험의 경우 최종 단계석션압인 $-0.8\;kg/cm^2$으로의 기간이 짧을수록 개량도가 크게 나타났다. 또한 각 석션압 단계 별 압밀도-적용기간 곡선 상의 변곡점을 이용하여 압밀효과를 극대화 시킬 수 있는 적용기간을 산정할 수 있었다.

• 복식
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• 제52권5호
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• pp.173-186
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• 2002

Street Style, occurred in British and America, has been expressed the character of the new generation by repeating developments and changes. Nowadays, pop music reflects the phase of society. and simultaneously it has influence on from culture to society. Rock Music was rooted in Country 8l western of America. Upon Country & Western, Afro-Americans Rhythm & Blues was added, and that was the birth of Rockabilly. Rockabilly developed to Rock'n 'roll and it started to change to various forms of Rock since 1950s. As the commercial impact and the breakthrough of teenagers emotion, the rock culture comprised the base of the youth culture. However. it formed the anti-establishment culture against the established value, accepting working class subculture. The teenager culture was affected by the Rock culture, also found relief in the opulence provided by the established generation, imitating it as it was. Simultaneously, it had a contrary aspect as anti-establishment form under the banner of revolt against languor in richness. The youth culture created street style that was escaped from high fashion, every time Rock music had changes. Since Street style was based on resistance of established culture and it fully refused vogue, it was indifferent from high fashion. The results of this study were as following. First, every time Rock music had changes, the new youth culture was concomitant with, the youth culture created street style. Secondly, rockahibilly style was characterized as diamond shaped design, embroidery, extra wide shirt collar, vivid contrast color . Rockers style was represented as metal studs, beads, denim, leather jacket, boots. Fusion of hippies style and Psychedelic, long hair, beads. worn denim were elements of headbangers style. Punks style was characterized as ripped T-shirt. rooster hair, over decorated jacket, short skirt. net or plastic T-shirt. Lastly, the firm relation between popular art and fashion was proved by examining the history of Rock Music and Street Style.

• 정보처리학회논문지B
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• 제9B권3호
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• pp.369-374
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• 2002

본 논문에서는 명암도 변화값과 기하학적 패턴벡터를 이용하여 실시간으로 차량번호판을 추출하고 인식하는 알고리즘을 제안하였다. 일반적으로 차량영상에서는 번호판 영역에서 문자와 배경이 뚜렷하게 구별되고, 일정한 명암도 변화를 가지면서 번호판 이외의 다른 영역보다 밀집도가 높은 특성이 있다. 따라서 본 논문에서는 이러한 성질을 이용하여 먼저 명암도 변화값을 사용하여 번호판을 추출하도록 하였으며 영상 입력과정에서 외부 환경에 따라 차량영상이 어둡거나 밝게 입력될 경우에도 동일한 추출 성능을 얻기 위하여 밝기 보정 과정을 수행하였다. 또한 추출된 번호판 영역으로부터 입력 문자의 크기, 이동 및 회전에 무관한 특성 추출을 위해 번호판 영역에서 잡음 제거와 세선화를 적용하여 전처리후 제안한 기하학적 패턴벡터를 이용하여 차량번호를 인식하도록 하였다. 제안한 방법들을 적용한 결과 기존의 원형 패턴벡터 보다 계산 속도가 빠르며, 차량번호판의 크기와 잡음에 무관하며, 불규칙한 조명 상태에서도 정확한 차량 번호를 인식할 수 있었다.

• Mycobiology
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• 제36권3호
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.

• Steel and Composite Structures
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• 제41권5호
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• pp.761-773
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• 2021

This study presents a 3D non-linear finite element (FE) assessment of dynamic soil-structure interaction (SSI). The numerical investigation has been performed on the time domain through a Finite Element (FE) system, while considering the nonlinear behavior of soil and the multi-directional nature of genuine seismic events. Later, the FE outcomes are analyzed to the recorded in-situ free-field and structural movements, emphasizing the numerical model's great result in duplicating the observed response. In this work, the soil response is simulated using an isotropic hardening elastic-plastic hysteretic model utilizing HSsmall. It is feasible to define the non-linear cycle response from small to large strain amplitudes through this model as well as for the shift in beginning stiffness with depth that happens during cyclic loading. One of the most difficult and unexpected tasks in resolving soil-structure interaction concerns is picking an appropriate ground motion predicted across an earthquake or assessing the geometrical abnormalities in the soil waves. Furthermore, an artificial neural network (ANN) has been utilized to properly forecast the non-linear behavior of soil and its multi-directional character, which demonstrated the accuracy of the ANN based on the RMSE and R² values. The total result of this research demonstrates that complicated dynamic soil-structure interaction processes may be addressed directly by passing the significant simplifications of well-established substructure techniques.

• Journal of Pharmaceutical Investigation
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• 제37권3호
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• pp.137-148
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• 2007

Using a strain-controlled rheometer [Rheometrics Dynamic Analyzer (RDA II)], the steady shear flow properties of a semi-solid ointment base (vaseline) have been measured over a wide range of shear rates at temperature range of $25{\sim}60^{\circ}C$. In this article, the steady shear flow properties (shear stress, steady shear viscosity and yield stress) were reported from the experimentally obtained data and the effects of shear rate as well as temperature on these properties were discussed in detail. In addition, several inelastic-viscoplastic flow models including a yield stress parameter were employed to make a quantitative evaluation of the steady shear flow behavior, and then the applicability of these models was examined by calculating the various material parameters (yield stress, consistency index and flow behavior index). Main findings obtained from this study can be summarized as follows : (1) At temperature range lower than $40^{\circ}C$, vaseline is regarded as a viscoplastic material having a finite magnitude of yield stress and its flow behavior beyond a yield stress shows a shear-thinning (or pseudo-plastic) feature, indicating a decrease in steady shear viscosity as an increase in shear rate. At this temperature range, the flow curve of vaseline has two inflection points and the first inflection point occurring at relatively lower shear rate corresponds to a static yield stress. The static yield stress of vaseline is decreased with increasing temperature and takes place at a lower shear rate, due to a progressive breakdown of three dimensional network structure. (2) At temperature range higher than $45^{\circ}C$, vaseline becomes a viscous liquid with no yield stress and its flow character exhibits a Newtonian behavior, demonstrating a constant steady shear viscosity regardless of an increase in shear rate. With increasing temperature, vaseline begins to show a Newtonian behavior at a lower shear rate range, indicating that the microcrystalline structure is completely destroyed due to a synergic effect of high temperature and shear deformation. (3) Over a whole range of temperatures tested, the Herschel-Bulkley, Mizrahi-Berk, and Heinz-Casson models are all applicable and have an almostly equivalent ability to quantitatively describe the steady shear flow behavior of vaseline, whereas the Bingham, Casson,and Vocadlo models do not give a good ability.

• Journal of Plant Biotechnology
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• 제34권1호
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• pp.11-17
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• 2007

수박작물의 대목용으로 사용하는 수박공대에 CGiMMV-CP 유전자를 도입하여 개발된 LM 수박공대의 CGMMV 내성 정도를 격리하우스와 노지 포장내에서 조사하였다. 격리온실에서의 $T_{3}$ 형질전환 수박대목의 CGMMV 내성은 접종 후 70일까지 유지되는 반면 대조구는 접종 후 20일에 전부 이병되었다. 인위적 토양전염 포장에서 형질전환체는 접종후71일까지 약 40%의 내성률을 보였으며, 대조구는 접종 후 37일에 모두 이병되었다. 인위적 접촉전염 포장에서 형질전환체는 대조구에 비해 약 10일 정도 지연효과를 보였다. 따라서 CGMMV-CP 형질전환체는 CGMMV에 저항성을 가진 것이 아니라 감염시기를 지연시키는 부분 내성으로 나타났다. CGMMV-CP homozygous T 세대를 진전시켜서 형질전환 수박공대 계통을 $BC_{1}T_{5}$ 세대에서 선발하였다. 또한 LM 수박공대에 형질전환 되지 않은 접수 (슈퍼금천수박)를 접목하여 non-LM 수박을 생산하고 CGMMV-CP 유전자에 관련된 물질의 이동 여부를 조사하였다. PCR, northern, western 분석한 결과 수박공대 대목에서 형성되는 DNA, RNA, protein 물질이 접수로 이동되지 않음을 확인하였다.

• 한국작물학회지
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• 제39권3호
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• pp.245-255
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• 1994

White clover는 많은 장점에도 불구하고 계속방목에 대한 적응력이 낮아 존속연한이 짧은 것이 결점이다. 따라서 본 시험은 white clover 혼파초지관리에 필요한 정보를 제공하기 위하여 예취주기의 장단(7일, 14일, 28일)이 28일의 재생기간동안 잎의 크기가 다른 white clover 품종들(Osceola, Huia, S184)의 수량과 재생에 미치는 영향을 조사하기 위하여 온실에서 pot 시험으로 실시한 바 그 결과를 요약하면 다음과 같다. 1. 28일의 처리기간중 수확 건물중은 대엽종 Osceola가 타품종에 비하여 많았고, 예취주기를 28일에서 7일로 줄임으로써 현저히 감소하였다. 2. 재생기간중 개체당 건물중은 주로 잎과 엽병의 증가에 기인하였고 예취 후 14일부터 대엽종 Osceola가 타품종에 비하여 많았다. 3. 개체당 엽면적과 복엽당 엽면적은 28일의 재생 기간동안 꾸준히 증가하였으나 예취를 28일에서 7일로 줄임으로써 현저히 감소하였다. 대엽종 Osceola의 개체당 엽면적과 복엽당 엽면적은 타품종에 비하여 많았다고 하나, 예취 후 28일의 개체당 엽면적에는 품종간 차이가 없는 것으로 측정되었다. 4. 예취주기를 짧게 할수록 엽수와 엽병장이 감소하였으며 예취 후 14일부터 타품종에 비하여 소엽종 S184가 많은 엽수를, 대엽종 Osceola가 긴 엽병을 확보하고 있는 것으로 조사되었다. 5. 개체당 포복경장과 분지경수는 재생기간동안 급격히 증가한 반면 소엽형 S184에서 가장 길고 많았으며 예취주기를 28일에서 7일로 줄임으로써 현저히 감소하였다.

• International Journal of Advanced Culture Technology
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• 제3권1호
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• pp.21-30
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• 2015

Ceramic foams are prepared as positive images corresponding to a plastic foam structure which exhibits high porosities (85-90%). This structure makes the ceramic foams attractive as a catalyst in a dry reforming process, because it could reduce a high pressure drop problem. This problem causes low mass and heat transfers in the process. Furthermore, the reactants would shortly contact to catalyst surface, thus low conversion could occur. Therefore, this research addressed the preparation of dry reforming catalysts using a sol-gel catalyst preparation via a polymeric sponge method. The specific objectives of this work are to investigate the effects of polymer foam structure (such as porosity, pore sizes, and cell characteristics) on a catalyst performance and to observe the influences of catalyst preparation parameters to yield a replica of the original structure of polymeric foam. To accomplish these objectives industrial waste foams, polyurethane (PU) and polyvinyl alcohol (PVA) foams, were used as a polymeric template. Results indicated that the porosity of the polyurethane and polyvinyl alcohol foams were about 99% and 97%. Their average cell sizes were approximate 200 and 50 micrometres, respectively. The cell characteristics of polymer foams exhibited the character of a high permeability material that can be able to dip with ceramic slurry, which was synthesized with various viscosities, during a catalyst preparation step. Next, morphology of ceramic foams was explored using scanning electron microscopy (SEM), and catalyst properties, such as; temperature profile of catalyst reduction, metal dispersion, and surface area, were also characterized by $H_2-TPR$ and $H_2-TPD$ techniques, and BET, respectively. From the results, it was found that metal-particle dispersion was relatively high about 5.89%, whereas the surface area of ceramic foam catalysts was $64.52m^2/g$. Finally, the catalytic behaviour toward hydrogen production through the dry reforming of methane using a fixed-bed reactor was evaluated under certain operating conditions. The approaches from this research provide a direction for further improvement of marketable environmental friendly catalyst production.