• 제목/요약/키워드: SDA

검색결과 117건 처리시간 0.031초

SDAR을 이용한 아스팔트 혼합물의 적용성 평가 (Application Evaluation of Asphalt mixtures using SDAR (Solvent DeAsphaltene Residue))

  • 양성린;임정혁;황성도;백철민
    • 한국도로학회논문집
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    • 제17권4호
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    • pp.53-61
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    • 2015
  • PURPOSES : The objective of this study is to evaluate the SDAR (solvent deasphaltene residue), which is obtained from the solvent deasphalting (SDA) process, as a pavement material. METHODS : The physical properties of the SDAR were evaluated based on its chemical composition, and asphalt mixtures with the SDAR were fabricated and used for the evaluation of mechanical properties. Firstly, the chemical composition of SARA (saturate, aromatic, resin and asphaltene) was analyzed using the TLC-FID (thin-layer chromatography-flame ionization detector). Moreover, the basic material properties of the asphalt binder with the SDAR were evaluated by the penetration test, softening point test, ductility test, and PG (performance grade) grade test. The rheological properties of the asphalt binder with the SDAR were evaluated by the dynamic shear modulus ($G^*$) obtained using the time-temperature superposition (TTS) principle. Secondly, the mechanical properties of the asphalt mixtures with the SDAR were evaluated. The compactibility was evaluated using the gyratory compacter. Moreover, the tensile strength ratio (TSR) was used for evaluating the moisture susceptibility of the asphalt mixtures (i.e., susceptibility to pothole damage). The dynamic modulus $E^*$, which is a fundamental property of the asphalt mixture, obtained at different temperatures and loading cycles, was used to evaluate the mechanical properties of the asphalt mixtures. RESULTS AND CONCLUSION : The SDAR shows stiffer and more brittle behavior than the conventional asphalt binder. As the application of the SDAR directly in the field may cause early failures, such as cracks on pavements, it should be applied with modifiers that can favorably modify the brittleness property of the SDAR. Therefore, if appropriate additives are applied on the SDAR, it can be used as a pavement material because of its low cost and strong resistance to rutting.

세계 시장을 주도하는 소형 가전의 품질평가 사례 연구 - 식품건조기를 중심으로 - (A Case Study on the Quality Evaluation of the Leading Small Domestic Appliances in the Global Market - Focusing on the Food Dehydrator -)

  • 김연성;김종만;서진영;임성욱;최정일;김서영
    • 품질경영학회지
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    • 제42권2호
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    • pp.253-264
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    • 2014
  • Purpose: The aim of this study is to gain a competitive advantage in the global marketplace by examining the current situation of three domestic Food Dehydrator companies' products. Food Dehydrators are sort of small domestic appliances(SDA), first introduced by Korean companies. Furthermore, this study suggests the improvement plans in the rapidly changing world situation. Methods: Evaluate through comparing three domestic Food Dehydrator companies' products based on the PQI(Premium Quality Index) model, developed by product quality evaluation experts group. Results: At first, we classified evaluation factors into three parts - usability quality, emotional quality - and each of the factors includes sub factors. Under this condition, the results of this study are as follows; the brand quality is remaining at a high satisfaction level compare to other two factors but emotional quality is assessed to be low. This study has shown at customers consider brand and usability quality factors as the most important factor due to the nature of the product. Conclusion: As the possibility of increasing customer needs such as product design and sensitive quality besides usability quality has risen in a competitive global market, the manufacturing companies in Korea are recommended to put forth the necessary effort to improve their product quality, especially in terms of emotional quality.

유연성 디스플레이 기판 소재용 투명성 폴리이미드의 합성 및 그의 나노복합화에 대한 연구 (Synthesis and Property of Colorless Polyimide and Its Nanocomposite for Plastic Display Substrate)

  • 마승락;김용석;이재흥;김정수;김인선;원종찬
    • 폴리머
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    • 제29권2호
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    • pp.204-210
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    • 2005
  • 플라스틱 디스플레이 기판용으로 사용하기 위하여 무색, 투명하면서 유연성, roll-to-roll 공정, 내열성과 저 열팽창계수 특성을 갖출 수 있는 폴리이미드에 대한 연구를 하였다. 3,3',4,4'-oxydiphthalic anhydride(ODPA), 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), sulfonyldianiline(3-SDA), aminophenoxybenzene(TPE-p, TPE-q, TPE-r)과 bis[4-(3-aminophenoxy)phenyl]sulfone(m-BAPS) 등을 사용하여 무색 투명한 폴리이미드를 합성하고 광학적 특성을 UV spectrophotometer, colormeter와 hazemeter를 이용하여 측정하였다. 열팽창계수(CTE)를 낮추기 위하여 층상실리케이트로 나노복합화하였다. 무색투명한 폴리이미드 필름은 440 nm에서 $89\%$ 이상의 광투과도와 yellow index(YI) 값이 7 이하의 우수한 광학 특성을 보였다. 나노복합화한 폴리이미드 필름은 층상실리케이트가 효과적으로 박리되어 층상실리케이트의 함유량이 증가함에 따라 열팽창계수가 감소하는 효과를 보였다.

레토르트 파우치 추어탕과 우렁 된장국의 세균상 조사 (Bacteriological Examination of Retort Pouched Loach Soup and Soybean Paste Soup Containing Mud Snail)

  • 박일웅
    • 한국식품영양학회지
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    • 제11권4호
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    • pp.431-436
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    • 1998
  • The present study is concerned with the bacteriological examination of retort pouched loach soup and soybean paste soup containing mud snail. It was found that before sterilization, viable cell counts (c.f.u/ml) in their media were for the loach soup 3.80${\times}$106 on TSA, 2.27${\times}$102 Endo agar, 5.20${\times}$102 on SS agar. With the culture media, SDA and TCBS, no microorgarnisms were isolated from the both soups. Sixteen species of microorgarnisms were identified for the unsterilized soups. In the loach soup on TSA, B. pantothenticus was the dominant species, followed by S. dysenteriae, C. sporogenes and some others were also identified, such on TSA, B. marinus was the dominant species, followed by S. aureus, S. saccharolytics and P. tetradius, S. adorifera, E. ictahuri, E. gergoviae, E. coli were also identified. On Endo agar, the two soups showed a similar bacteriological pattern, in which entrobacterium such as E. gergoviae and E. coli were identified. Particularly K. subsp. rhinoscleromatis for the loach soup. On SS agar, S. ficaria and P. prevotii in the loach soup, S. ficaria and P. tetradius in the soybean paste soup were identified respectively. Bacteriological examination was also carried out for the spoiled retort pouched soup in the market, in which thirteen microorgarnisms were isolated and its pattern almost similar to that before sterilzation. They were B. pantothenticus, S. dysenteriae, C. sporogenes, P. gergoviae, E. ictaluri, S. ficaria, K. subsp. rhinoscleromatis in the loach soup and B. marinus, S. aureus, S. saccharolytics, P. tetradius, E. ictaluri, S. ficaria, S. adorifera in the soybean soup.

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개선된 Woodward-Lawson 샘플링법을 사용한 불균일 결합선로형 트랜스버설 필터 설계 (Design of Nonuniform Coupled Line-Type Transversal Filters Using Improved Woodward-Lawson Sampling Method)

  • 정현수;전상재;박의준
    • 한국전자파학회논문지
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    • 제16권2호
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    • pp.120-127
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    • 2005
  • 연속적으로 연결된 방향성 결합기를 사용한 트랜스버설 필터 설계 방법을 제안하였다. 그 결합기형 트랜스버설 필터는 연속적으로 변화하는 불균일 결합선로로 간주될 수 있다. 이 설계 방법은 결합도 주파수 특성 패턴이 갖는 극점을 제어함으로써 원하는 결합도의 최적값을 도출하는데 기반을 두며, 이 최적화 과정에서 Woodward-Lawson 샘플링법을 개선 및 적용시키므로서 트랜스버설 필터가 갖는 분포된 지연요소와 가중치 요소를 쉽게 합성할 수 있도록 하였다. 응용을 위해 스펙트럴 영역법을 사용하여 마이크로스트립 트랜스버설 필터를 제작하고 결합기의 모드 위상속도 보상을 위해 최적한 유전체 덮개층을 적용시켰다. 실험결과로부터 제안한 방법의 타당성을 검증하였다.

Identification and molecular characterization of a low acid phosphatase 3 (lap3) mutant based on the screening of an Arabidopsis activation-tagged population

  • Jin, Yong-Mei;Won, So-Youn;Jeon, Hye-Sung;Park, Sang-Ryoung;Kim, Min-Kyun
    • Plant Biotechnology Reports
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    • 제5권1호
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    • pp.45-51
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    • 2011
  • A low acid phosphatase 3 (lap3) mutant was identified and characterized from an Arabidopsis activation-tagged (Weigel) population. The roots of the lap3 plants showed lower acid phosphatase (APase) activity compared to wild-type ones under low-Pi conditions ($10{\mu}M\;Pi$). Plasmid rescue experiments revealed that the activation-tagging vector was inserted into the intergenic region between At4g31540 and At4g31550 in the Arabidopsis genome. The genotypic segregation of the lap3 mutation was tightly linked with the phenotypic segregation of root APase activity in the prgeny of lap3. The transcript level of the At4g31520 (SDA1: SEVERE DEPOLYMERIZATION OF ACTIN 1), located 7.4 kb from the CaMV 35S enhancers in the lap3 mutant, was significantly reduced compared to that in the wild type. It was speculated that cellular actin polymerization may be involved in Pi acquisition in higher plants.

산란계에서의 전신 다발성 육아종성 Aspergillosis 발생 (Multisystemic Aspergillosis with Granulomas in Layer Chickens)

  • 김지예;김종만;모인필
    • 한국가금학회지
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    • 제38권1호
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    • pp.45-50
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    • 2011
  • 본 증례는 국내의 산란계 농장에서 사육 중이던 39일령 산란계 중추계군에서 신경 증상을 동반한 폐사를 나타내며, 부검 시 폐를 포함한 뇌, 간, 신장 등의 실질장기에서 직경 1~5 mm 크기의 황백색 결절이 다수 관찰되었다. 병리조직학적으로 다발성의 육아종성 병변이 폐, 뇌, 신장, 비장 등에서 관찰되었으며, 특히 폐의 결절 형성 및 건락성 육아종성 병변이 심한 정도로 나타나 호흡기를 통해 1차 감염이 이루어진 것을 확인할 수 있었다. 육아종성 결절을 SDA에 배양하여 집락의 색을 확인하고, 균사체의 Giemsa 염색 및 조직학적 병변상에서 PAS 염색 결과를 통해 Aspergillus 속 곰팡이인 것으로 확인할 수 있었고, 배양된 균사에 대한 유전학적 검사 결과 Aspergillus flavus로 동정되었다. A. flavus 균사는 폐, 뇌, 신장 및 선위에서 병변 중심부 및 변연부 모두에서 관찰되었고, 다핵 거대세포 및 섬유아세포가 염증세포들과 함께 둘러싸고 있는 것이 확인되었다. 특히 대뇌에서의 육아종성 병변 및 그로 인한 신경 증상이 임상 증상으로 발현된 것이 본 증례의 특징적인 소견이다.

디인터레이싱을 위한 방향지향 보간법의 개선 (Improvement of Direction-Oriented Interpolation for Deinterlacing)

  • 박도영;이연경;유훈
    • 한국정보통신학회논문지
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    • 제18권9호
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    • pp.2209-2215
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    • 2014
  • 본 논문은 DOI방법을 개선한 디인터레이싱 방법을 제안한다. DOI방법은 강력한 인트라필드 기반의 디인터레이싱 기술이지만 긴 연산시간과 주기적인 패턴에서 방향을 잘못 찾는 문제를 가지고 있다. 이 문제를 해결하기 위해 기존의 전역검색 대신하여 2단계 검색을 하여 연산속도를 향상시키고 두 가지 과정을 추가하여 영상의 화질을 개선하는 방법을 제안한다. 첫 번째 단계로 잘못된 방향으로 찾은 공간벡터를 삭제하며 두 번째 단계로 찾지 못한 방향에 대한 공간 방향벡터를 삽입함으로써 제안된 방법에서 잘못 찾은 공간 방향벡터를 정확한 결과인지 재확인하여 픽셀의 보간에 사용할지 검사한다. ISO 실험 이미지를 이용하여 제안된 방법과 line evarage, edge-based line averaging, DOI, selective deinterlacing algorithm 등의 기존의 방법을 비교한 결과 제안된 방법이 객관적으로나 주관적으로 우 수하다는 것을 보였다.

Prediction of Listeria monocytogenes Growth Kinetics in Sausages Formulated with Antimicrobials as a Function of Temperature and Concentrations

  • Bang, Woo-Suk;Chung, Hyun-Jung;Jin, Sung-Sik;Ding, Tian;Hwang, In-Gyun;Woo, Gun-Jo;Ha, Sang-Do;Bahk, Gyung-Jin;Oh, Deog-Hwan
    • Food Science and Biotechnology
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    • 제17권6호
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    • pp.1316-1321
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    • 2008
  • This study was conducted to develop a model to describe the effect of antimicrobials [potassium sorbate (PS), potassium lactate (PL), and combined PL and sodium diacetate (SDA, PLSDA)] on the growth parameters of Listeria monocytogenes such as specific growth rate (SGR) and lag phase periods (LT) in air-dried raw sausages as a function of storage temperature (4, 10, 16, and $25^{\circ}C$). Results showed that the SGR of L monocytogenes was dependent on the storage temperature and level of antimicrobials used. The most effective treatment was the 4% PLSDA, followed by the 2% PLSDA and 4% PL and 0.2% PS exhibited the least antimicrobial effect. Increased growth rates were observed with increasing storage temperatures from 4 to $25^{\circ}C$. The growth data were fitted with a Gompertz equation to determine the SGR and LT of the L. monocytogenes. Six polynomial models were developed for the SGR and LT to evaluate the effect of PS (0.1, 0.2%) and PL (2,4%) alone and PLSDA (2, 4%) on the growth kinetics of L. monocytogenes from 4 to $25^{\circ}C$.

Historical Review and Future of Cardiac Xenotransplantation

  • Jiwon Koh;Hyun Keun Chee;Kyung-Hee Kim;In-Seok Jeong;Jung-Sun Kim;Chang-Ha Lee;Jeong-Wook Seo
    • Korean Circulation Journal
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    • 제53권6호
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    • pp.351-366
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    • 2023
  • Along with the development of immunosuppressive drugs, major advances on xenotransplantation were achieved by understanding the immunobiology of xenograft rejection. Most importantly, three predominant carbohydrate antigens on porcine endothelial cells were key elements provoking hyperacute rejection: α1,3-galactose, SDa blood group antigen, and N-glycolylneuraminic acid. Preformed antibodies binding to the porcine major xenoantigen causes complement activation and endothelial cell activation, leading to xenograft injury and intravascular thrombosis. Recent advances in genetic engineering enabled knock-outs of these major xenoantigens, thus producing xenografts with less hyperacute rejection rates. Another milestone in the history of xenotransplantation was the development of co-stimulation blockaded strategy. Unlike allotransplantation, xenotransplantation requires blockade of CD40-CD40L pathway to prevent T-cell dependent B-cell activation and antibody production. In 2010s, advanced genetic engineering of xenograft by inducing the expression of multiple human transgenes became available. So-called 'multi-gene' xenografts expressing human transgenes such as thrombomodulin and endothelial protein C receptor were introduced, which resulted in the reduction of thrombotic events and improvement of xenograft survival. Still, there are many limitations to clinical translation of cardiac xenotransplantation. Along with technical challenges, zoonotic infection and physiological discordances are major obstacles. Social barriers including healthcare costs also need to be addressed. Although there are several remaining obstacles to overcome, xenotransplantation would surely become the novel option for millions of patients with end-stage heart failure who have limited options to traditional therapeutics.