• Composites Research
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• 제26권3호
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• pp.160-164
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• 2013

In this study, the effect of phosphoric acid (PA) as a fiber spinning aid on the strength increase of polyacrylonitrile (PAN) nano-fibers by using modified mechano-electrospinning technologies has been analyzed. The medium carbonization temperature of $800^{\circ}C$ has been selected for the future economic production of these new materials. The concentration of PAN in dimethyl sulfoxide (DMSO) was fixed as 5 wt%. The weight fraction of PA was selected as being 2%, 4%, 6%, and 8% in comparison to PAN. These solutions have been used to make the nanofibers. The mechano-electrospinning apparatus installed in KRICT was made by our own design. By using this apparatus the continous and highly aligned precursor nano-fibers have been obtained. The bundle of 50 well aligned nano diameter continuous fibers with the diametr of 10 microns with 6 wt% phosphoric acid for addition showed maximum mechanical properties of 1.6 GPa as tensile strength and 300 GPa as Young's modulus. The weight of final product can be increased 19%, which can improve the economical benefits for the application of these new materials.

• Fibers and Polymers
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• 제4권3호
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• pp.124-128
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• 2003

Dark brown Alpaca fiber was reduced in shade via selective bleaching with peroxide. Two selective oxidative bleaching methods were tested on alpaca top to assess their effectiveness for color removal and fiber quality properties. Color change, bundle strength, weight loss, fiber diameter, surface modification, dye-ability and dye wash fastness were assessed for both methods and compared with the original brown top. Bleach method 1 (BL-I) showed little surface modification, 5.8% weight loss and 2.4% strength loss. D1925 yellowness index was reduced to 74.3 from 83.1 and provided a good base for the dyeing of medium to deep shades. Bleach method 2 (BL-II) displayed considerable surface modification, 7.8% weight loss and 18% strength loss. BL-II also resulted in a mean diameter reduction of 1.9 micron during bleaching. Yellowness was reduced to 64.5 from 83.1 and provided a very good base for the dyeing of medium to deep shades. BL-I showed better exhaustion of the premetallised dye Lanaset Violet B than BL-II. Wash fastness for BL-II was 1 grey scale unit poorer than BL-I. BL-II showed far better color clarity at pale depths however the wash fastness of the finished product was not good enough to maintain the depth or clarity of the color. BL-I showed poorer clarity of color but exhibited better wash fastness results.

• 한국유통학회지:유통연구
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• 제16권1호
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• pp.117-140
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• 2011

마케팅 연구에서 판매촉진은 지난 수십 년간 지속적으로 연구되어 온 분야중의 하나이다. 판매촉진은 소비자의 지각된 가치를 증가시키는 방법으로 크게 2가지 유형으로 나누어 볼 수 있는데, 첫째, 소비자에게 비용을 줄여주는 방법인 가격인하 판매촉진과 둘째, 소비자에게 혜택을 제공하여 전체적인 지각된 가치를 높여주는 부가가치 제공 판매촉진 방법이 그것이다. 그 동안의 판매촉진의 연구를 살펴보면 주로 가격할인 판매촉진을 중심으로 연구가 많이 이루어졌음을 알 수 있다. 그러나 최근 들어 부가가치 제공 판매촉진 방법에 관한 연구가 증가하고 있는 추세이다. 특히, 부가가치 제공 판매촉진 활동의 효과 평가, 적절한 부가가치 판매촉진 방법, 구매의도에 관한 연구가 많이 이루어졌음을 확인할 수 있다. 즉, 판매촉진 자체에 초점을 맞춘 연구가 대부분이었다. 본 연구는 부가가치적 판매촉진이 판매촉진 제품의 가치평가에 미치는 영향에 대해 살펴보고자 한다. 부가가치 판매촉진에 관심을 갖게 된 이유는 부가가치 판매촉진은 상황적인 요인에 의해 그 것이 혜택으로 지각될 수도 있지만 반드시 그렇지 않을 수도 있기 때문이다. 본 연구는 이러한 상황적 요인으로 사은품 제시 방법과 유통업체의 불확실성 수준이라는 2가지 요인이 판매촉진 제품의 가치평가에 미치는 영향을 알아보기 보기위해 실험과 준실험을 이용한 2가지 연구를 실시하였다. 먼저 실험은 2(사은품 제시방법; 통합제시 vs. 분리제시) *2(유통업체의 불확실성 수준(높음 vs. 낮음) *3(평가대상; 전체제품(본 제품+사은품), 본 제품, 사은품)로 집단 간 실험설계를 하였다. 그 결과 사은품을 통합 제시하는 경우가 분리 제시하는 경우에 비해 제품 가치 평가를 더 높게 하는 것으로 나타났으며, 유통업체 불확실성 수준이 높은 경우가 낮은 경우에 비해 전체 제품 가치 평가를 더 낮게 하는 것으로 나타났다. 이 두 요인의 상호작용을 살펴본 결과, 전체적으로 살펴보았을 때 상호작용은 유의미하게 나타나지 않았다. 하지만 보다 상세한 결과를 알아보기 위해 각각의 평가 대상별로 알아본 결과, 본 제품 평가에 있어서 유통업체 불확실성이 높은 경우에 통합 제시하는 경우가 분리제시 하는 경우에 비해 제품 가치를 더 낮게 평가하는 것으로 나타났다. 준실험인 연구 2는 연구 1의 결과를 재확인하기 위한 것으로 실제 시장에서 행해지고 있는 제품과 최근에 이용한 유통업체에 대해 평가하게 하였다. 그 결과 연구 1에서처럼 유통업체 불확실성이 높은 경우 제품 가치 평가를 더 낮게 하는 것으로 나타났다. 특히 연구 1에서 살펴보지 않았던 구매의도를 조사하였다. 부가가치 판매촉진 이전의 유보가격과 부가가치 판매촉진 자극물을 본 이후의 유보가격의 차이를 이용하여 2개의 집단으로 나눈 후, 구매의도를 비교한 결과 두 집단 간 구매의도에는 차이가 없는 것으로 나타났다. 본 연구 결과를 통해 유통업체 불확실성이 높은 경우, 사은품을 제공하는 것이 소비자에게 단순히 혜택으로 지각되는 것이 아니라 상술지각이 활성화되어 오히려 제품 평가에 부정적인 영향을 미치게 되며 구매를 망설이게 한다고 볼 수 있다.

• 한국막학회:학술대회논문집
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• 한국막학회 2002년도 제10회 하계 Workshop
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• pp.1-12
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• 2002

Desalination by reverse osmosis (RO), which first entered commercial use in the 1970s, was initially mainly used for treating brackish water. Technological progress led to the development of an RO membrane enabling single-pass seawater desalination. Toyobo succeeded in developing a single-pass seawater desalination RO module composed of hollow fiber type membranes made of cellulose triacetate in 1978, and then in 1979 began production of the first commercially available double-element module. This double-element module has many advantages suitable for seawater desalination. It has high chlorine tolerance and high salt rejection, derived from the properties of the membrane material, and it is highly resistant to fouling and scaling matters due to the unique flow pattern and fiber bundle configuration. These advantages help to explain why the Toyobo double-element module has been used so successfully at the many seawater desalination plants around the world. Since the 1980s, large plants capable of desalinating several tens of thousands of cubic meters a day have sprung up around the Mediterranean and In the Middle East. The Jeddah RO Phase I Plant, which has a capacity of 56, 800m$^3$/day, went into operation in 1989. In 1994, the same sized Phase II Plant came on stream, giving the plant a huge total capacity of 113, 600m$^3$/day. The plant constructor Mitsubishi Heavy Industries, Ltd. (MHI), and the RO membrane manufacturer Toyobo Co., Ltd. In 1998, the world's largest RO seawater desalination plant in operation, which has a capacity of 128, 000m$^3$/day and is run by Saudi Arabia's Saline Water Conversion Corporation (SWCC), went into operation at Yanbu. RO seawater desalination technology has thus already reached the stage of full-scale commercial use. In order to encourage its wider use, however, RO desalination needs to be made more economical by lowering construction and water treatment costs. Toyobo has therefore developed a new economical RO desalination system by a recovery ratio of 60% using a high-pressure module with a high product flow rate. In 2000, Toyobo high recovery membrane module was selected for the largest seawater desalination plant in Japan, which has a capacity of 50, 000m$^3$/day.

• 항공우주기술
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• 제13권2호
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• pp.80-86
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• 2014

본 연구에서는 다목적실용위성 3호 영상을 이용하여 지표면 상의 정규식생지수 비교 분석 하고자 한다. 산출된 다목적실용위성 3호의 정규식생지수 비교 분석을 위해 동일 지점 최소 관측 시간 오차를 가지는 고해상도 GeoEye 영상이 사용되었다. 먼저, 각 밴드별 분광 정도 산출을 위해 대기 보정이 수행되었다. 대기 보정 수행을 위한 기하 정보는 다목적실용위성 3호 보조자료에 포함된 태양천정각, 태양방위각, 위성천정각, 위성방위각, 날짜 정보이다. 그리고 대기 요소에 의한 감쇄, 산란, 흡수 정보를 물리적으로 계산하기 위해 수증기량, 오존량, 에어러솔 정보가 적용되었다. 일반적으로 정확한 대기정보를 얻기 위해서는 현장관측자료가 중요하지만, 본 연구에서는 MODIS atmospheric products를 사용하였고, 대기보정 모델에서 산출된 지면 반사도는 식생지수 산출에 사용되었다.

• Nuclear Engineering and Technology
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• 제54권5호
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• pp.1825-1834
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• 2022

Performing high-fidelity computational fluid dynamics (HF-CFD) to predict the flow and heat transfer state of the coolant in the reactor core is expensive, especially in scenarios that require extensive parameter search, such as uncertainty analysis and design optimization. This work investigated the performance of utilizing a multi-fidelity reduced-order model (MF-ROM) in PWR rod bundles simulation. Firstly, basis vectors and basis vector coefficients of high-fidelity and low-fidelity CFD results are extracted separately by the proper orthogonal decomposition (POD) approach. Secondly, a surrogate model is trained to map the relationship between the extracted coefficients from different fidelity results. In the prediction stage, the coefficients of the low-fidelity data under the new operating conditions are extracted by using the obtained POD basis vectors. Then, the trained surrogate model uses the low-fidelity coefficients to regress the high-fidelity coefficients. The predicted high-fidelity data is reconstructed from the product of extracted basis vectors and the regression coefficients. The effectiveness of the MF-ROM is evaluated on a flow and heat transfer problem in PWR fuel rod bundles. Two data-driven algorithms, the Kriging and artificial neural network (ANN), are trained as surrogate models for the MF-ROM to reconstruct the complex flow and heat transfer field downstream of the mixing vanes. The results show good agreements between the data reconstructed with the trained MF-ROM and the high-fidelity CFD simulation result, while the former only requires to taken the computational burden of low-fidelity simulation. The results also show that the performance of the ANN model is slightly better than the Kriging model when using a high number of POD basis vectors for regression. Moreover, the result presented in this paper demonstrates the suitability of the proposed MF-ROM for high-fidelity fixed value initialization to accelerate complex simulation.

• Nuclear Engineering and Technology
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• 제38권2호
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• pp.163-174
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• 2006

The $Ph{\acute{e}}bus$ FP project is an international reactor safety project. Its main objective is to study the release, transport and retention of fission products in a severe accident of a light water reactor (LWR). The FPT4 test was performed with a fuel debris bed geometry, to look at late phase core degradation and the releases of low volatile fission products and actinides. Post Test Analyses results indicate that releases of noble gases (Xe, Kr) and high-volatile fission products (Cs, I) were nearly complete and comparable to those obtained during $Ph{\acute{e}}bus$ tests performed with a fuel bundle geometry (FPT1, FPT2). Volatile fission products such as Mo, Te, Rb, Sb were released significantly as in previous tests. Ba integral release was greater than that observed during FPT1. Release of Ru was comparable to that observed during FPT1 and FPT2. As in other $Ph{\acute{e}}bus$ tests, the Ru distribution suggests Ru volatilization followed by fast redeposition in the fuelled section. The similar release fraction for all lanthanides and fuel elements suggests the released fuel particles deposited onto the plenum surfaces. A blockage by molten material induced a steam by-pass which may explain some of the low releases. The revaporisation testing under different atmospheres (pure steam, $H_2/N_2$ and steam /$H_2$) and up to $1000^{\circ}C$ was performed on samples from the first upper plenum. These showed high releases of Cs for all the atmospheres tested. However, different kinetics of revaporisation were observed depending on the gas composition and temperature. Besides Cs, significant revaporisations of other elements were observed: e.g. Ag under reducing conditions, Cd and Sn in steam-containing atmospheres. Revaporisation of small amounts of fuel was also observed in pure steam atmosphere.

• 약학회지
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• 제45권5호
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• pp.513-521
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• 2001

The chronic cholestasis induce to biliary liver fibrosis (cirrhosis) and the increased products of ROS(reactive oxygen species) cause to the liver damage. In this study ; the antioxidant and antifibrotic effect of dried extracts of oriental medicine (DW) was investigated under the liver fibrotic (cirrhotic) condition. The female Sprague-Dawley rats were divided in 5 groups (Normal, Op-2, Op-4, OpDW-2, OpDW-4). Except for normal group, the rats were induced to biliary liver fibrosis (cirrhosis) by the operation of bile duct ligation/scission (BDU/S) and were observed in 2 weeks or 4 weeks. And the prepared DW was treated p.o.2 ml/day/rats in 2 weeks or 4 weeks for OpDW groups. At the time of sacrifice, the liver, kidney, spleen were weighed and the ratio of organ weight/body weight was calculated. The MDA, the hyp and biochemical parameters (GOT GTP, ALP, t-bili) were measured in sera and liver tissue of rats. The biochemical change was observed on liver tissue. In the result, the hepatomegaly and spleenomegaly appeared in all BDL/S operated rats, and significantly lower liver weight was observed in OpDW-4 group compared with in Op-4 group (p<0.05). The level of clinical parameters in sera of all liver fibrosis (cirrhosis) developed rats was higher than in normal group. Especial1y, the value of GOT in OpDW-2 group and ALP in OpDW-4 group showed significantly lower than in Op-2 group and Op-4 group (p<0.01, p<0.005). The content of hyp in all operation groups was significantly higher than in normal group (p<0.05∼<0.005), and showed significantly lower value in the OpDW-4 group than in Op-4 group (p<0.05). The product of lipid peroxidationUDA) increased significantly under the fibrotic(cirrhotic) condition (p<0.05∼ <0.005), and the MDA value in OpDW-4 group decreased significantly in Op-4 group (p<0.005). The histological change (bile duct proliferation, fibrosis, collagen bundle) was similarly observed in Op-2 group and in OpDW-2 group, but the weak fibrosis and bile duct proliferation were observed in OpDW-4 group compared with in Op-4 group. In conclusion, lipid peroxidation and severe liver damage were activated by bile duct obstruction, and the measurement of MDA and hap can be useful monitor for the screening of antioxidant and antifibrotic effect in experimental liver fibrosis (cirrhosis). The 4 weeks treatment with DW extracts suppressed lipid peroxidation and inhibited fibrotic (cirrhotic) process in BDL/S operated rats.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.3104-3104
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• 2001

The research described here was undertaken with the aim of monitoring, optimizing and ultimately controlling the production of heterofermentative microbes used as starters in the salami industry. The use of starter cultures in the fermented meats industry is a well-established technique used to shorten and standardize the ripening process, and to improve and control the organoleptic quality of the final product. Starter cultures are obtained by the submerged cultivation of suitable microorganisms in stirred, and sometimes aerated, fermenters where monitoring of key physiological parameters such as the concentration of biomass, substrates and metabolites suffers from the general lack of real-time measurement techniques applicable to aseptic processes. In this respect, the results of the present work are relevant to all submerged fermentation processes. Previous work on the application of on-line NIR spectroscopy to the lactic acid fermentation (Dosi et al. - Monreal NIR1995) had successfully used a system based on a measuring cell included in a circulation loop external to the fermenter. The fluid handling and sterility problems inherent in an external circulation system prompted us to explore the use of an in-line system where the NIR probe is immersed in the culture and is thus exposed to the hydrodynamic conditions of the stirred and aerated fluid. Aeration was expected to be a potential source of problems in view of the possible interference of air bubbles with the measurement device. The experimental set-up was based on an in-situ sterilizable NIR probe connected to the instrument by means of an optical fiber bundle. Preliminary work was carried out to identify and control potential interferences with the measurement, in particular the varying hydrodynamic conditions prevailing at the probe tip. We were successful in defining the operating conditions of the fermenter and the geometrical parameters of the probe (flow path, positioning, etc.) were the NIR readings were reliable and reproducible. The system thus defined was then used to construct and validate calibration curves for tile concentration of biomass, carbon source and major metabolites of two different microorganisms used as salami starters. Real-time measurement of such parameters coupled with the direct interfacing of the NIR instrument with the PC-based measurement and control system of the fermenter enabled the development of automated strategies for the interactive optimization of the starter production process.

• 만화애니메이션 연구
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• 통권46호
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• pp.207-231
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• 2017

판화는 순수예술의 한 분야이면서 에디션(edition)이라는 특수성 때문에 대중적인 성격을 띤 상업적 결과물로 인식되는 모호한 경계에 놓여져 있다. 현대의 과학기술 발전은 판화의 새로운 기법을 발달시켰고 디지털(digital)이라는 컴퓨터와의 융합은 복제예술로서의 가능성을 보여주었다. 복제 판화는 사진과 접하며 확장된 영역으로의 지대한 영향을 받았고 프린트의 다양한 형태는 간접예술의 가능성을 여러 각도로 자극함으로써 많은 변화와 시도를 가져왔다. 판화와 과학기술의 역사가 밀접하게 관련되어 있듯이 컴퓨터의 발달은 복수예술성의 광범위한 영역확대, 기술적, 예술적 변화를 시도하게 만든다. 디지털이 갖는 매끈한 평면위에 판화의 물성을 얹음으로 단순히 복사된 이미지 위에 새로운 개념의 형상을 만들어낼 수 있는 과정과 결과는, 일품미술의 가치 혹은 판화가 주는 물성의 특성과는 또 다른 독특한 작품의 영역을 보여준다. 복제성에 대한 폄하된 인식은 판화와 직결된 의미로 작품의 가치를 평가하였고 복제된 각 에디션의 가치와는 무관하게 한 묶음의 작품으로 평가절하 되는 것은 부인 할 수 없는 사실이다. 그러나 종이 위에 찍혔던 판화의 물성은 캔버스위에 손으로 직접 그리는 핸드드로잉(hand drawing)과 함께 올려지고, 디지털 프린트라는 정보의 종이위에 결합하는 과정을 통해 새로운 면모와 변화를 보여주는 계기가 된다. 매체가 주는 다양성은 예술과 과학기술사이에서 때로는 정체성의 논란이 되기도 한다. 앞으로 예술의 영역에서 누릴 수 있는 매체성의 한계를 어떤 기준으로 정할 수 있을지도 논의가 되어야 할 것이다.