• Title/Summary/Keyword: 좋은재료

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The Effects of Na2CO3 on Early Strength of High Volume Slag Cement (대량치환 슬래그 시멘트의 초기강도에 미치는 Na2CO3의 영향)

  • Kim, Tae-Wan;Hahm, Hyung-Gil
    • Journal of the Korea Concrete Institute
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    • v.28 no.3
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    • pp.349-356
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    • 2016
  • This report presents the results of an investigation on the early strength development of pastes high volume slag cement (HVSC) activated with different concentration of sodium carbonate ($Na_2CO_3$). The ordinary Portland cement (OPC) was replaced by ground granulated blast furnace slag (GGBFS) from 50% to 90% by mass, the dry powders were blended before the paste mixing. The $Na_2CO_3$ was added at 0, 2, 4, 6, 8 and 10% by total binder (OPC+GGBFS) weight. A constant water-to-binder ratio (w/b)=0.45 was used for all mixtures. The research carried out the compressive strength, ultrasonic pulse velocity (UPV), water absorption and X-ray diffraction (XRD) analysis at early ages(1 and 3 days). The incase of mixtures, V5 (50% OPC + 50% GGBFS), V6 (40% OPC + 60% GGBFS) and V7 (30% OPC + 70% GGBFS) specimens with 6% $Na_2CO_3$, V8 (20% OPC + 80% GGBFS) and V9 (10% OPC + 90% GGBFS) specimens with 10% $Na_2CO_3$ showed the maximum strength development. The results of UPV and water absorption showed a similar tendency to the strength properties. The XRD analysis of specimens indicated that the hydration products formed in samples were CSH and calcite phases.

Applicability of a Photosynthetic Ciliate, Mesodinium rubrum MR-MAL01 -Usefulness as a Live Prey Species for the Marine Aquaculture of Bivalves- (광합성 섬모류 Mesodinium rubrum MR-MAL01의 응용성(1) 이매패류 종묘생산을 위한 먹이생물 유용성)

  • 김형섭;명금옥;조수근;이원호
    • Journal of Aquaculture
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    • v.17 no.2
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    • pp.115-121
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    • 2004
  • In a series of feeding experiments using the newly established the first laboratory strain of a temperate photosynthetic ciliate, Mesodinium rubrum MR-MAL01, direct evidence was obtained for ingestion of the cultured M. rubrum cells by the bivalves like the Korean scallop, Chlamys farreri and Manila clam. Ruditapes phil-ippinarum. Each experimental Korean scallop and Manila clam removed up to 9,590 and 23,200 cells min-1, respectively. Small particles almost identical to the ruptured cells of MR-MAL01 culture were observed in the gut of the experimental bivalves, although no intact M. rubrum cell was found. In a 28 days rearing experiment, Isoshrysis galbana (KMCC H-2), a microalga, supported better growth of small Manila clam spat (0.46 mm in shell length) than MR-MAL01 strain. For the large Manila clam spat (0.84 mm in shell length), however. MR-MAL01 strain was a better prey item. Mass culture methods for this photosynthetic marine ciliate may be developed for use as live feed in aquaculture of the spat and broodstock of bivalve and small-mouthed fish larvae.

A Study on the Effect of the Importance of Selection Attributes for Chicken Specialty Store on Customer Satisfaction and Loyalty : Focusing on Undergraduate and Graduate Students in Daejeon City (치킨 전문점의 선택속성 중요도가 고객만족 및 고객충성도에 미치는 영향에 관한 연구 (대전지역 대학생.대학원생을 중심으로))

  • Kwon, Nam-Wook;Oh, Suk-Tae
    • Culinary science and hospitality research
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    • v.17 no.4
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    • pp.169-184
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    • 2011
  • This study tried to know the effect of selection attributes for chicken specialty stores on customer satisfaction and loyalty. IPA analysis on relation between the attributes and the satisfaction showed that most quality-related product attributes such as 'the taste and quality of chicken', 'proper portion', and 'fresh ingredients' had high levels of perceived importance and satisfaction. It indicates that the stores need to keep the current good quality. On the other hand, customers showed lower levels of satisfaction in 'reasonable prices', 'quick delivery'(certainty factors), and 'kindness of employees', so that those attributes need improving. The hypothesis testing showed that supplementary product factors such as 'side dishes offered with chicken', 'use of neat and convenient wrapping package', and 'coupon offers' among the customer selection attributes had a significant impact on customer satisfaction and loyalty. Therefore, the owners of chicken specialty stores need to choose a reasonable price to make customers satisfied and shorten delivery time directly related to quality. Also, they need to differentiate their services by continuous employee training and education and provide additional services in order to enhance customer satisfaction for their repurchase.

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Comparative study of two CAD software programs on consistency between custom abutment design and the output (두 가지 CAD software의 맞춤형 지대주 디자인과 출력물 일치도 비교)

  • Lim, Hyun-Mi;Lee, Kyu-Bok;Lee, Wan-Sun;Son, KeunBaDa
    • Journal of Dental Rehabilitation and Applied Science
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    • v.34 no.3
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    • pp.157-166
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    • 2018
  • Purpose: This study was aimed to compare the consistency between the custom abutment design and the output in two CAD software programs. Materials and Methods: Customized abutments were designed by using 3Shape Dental System CAD software and Delta9 CAD software on a plaster model with implants (CRM STL file). After milling of the designed abutments, the abutments were scanned with a contact method scanner (Test STL file). We overlaid the Test STL file with each CRM STL file by using inspection software, and then compared the milling reproducibility by measuring the output error of the specimens from each CAD software program. Results: The Delta9 showed better milling reproducibility than 3Shape when comparing the milling errors obtained with a full scan of all specimens (P < .05) and also when comparing the axial wall region specifically according to the axial angle. With 0.9 mm marginal radius, the Delta9 showed better consistency between the design and the output than 3Shape (P < .05). While, anti-rotation form had no significant difference in error between the two systems. When cumulative errors were compared, the Delta9 showed better milling reproducibility in almost cases (P < .05). Conclusion: Delta9 showed a significantly smaller error for most of the abutment design options. This means that it is possible to facilitate generation of printouts with reliable reproducibility and high precision with respect to the planned design.

A Soil Mechanical Study for a Practical Application to Forest Road Construction (임도설계(林道設計)에의 응용(應用)을 위한 흙의 토질(土質) 역학적(力學的) 특성(特性))

  • Kim, Ki Weon
    • Journal of Korean Society of Forest Science
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    • v.84 no.2
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    • pp.166-177
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    • 1995
  • This study was carried out to discuss how soils in the area planned for a forest road construction can be mechanically tested and practically applied. For this, 16 soil test samples from 8 plots(2 samples per plot) were used. The major tests are focused on unit weight before and after cut, water content, liquid and plastic limits, sieve and hydrometer analysis etc. The total unit weight(${\rho}_t$) before and after cut are $1.69g/cm^3$ and $1.19g/cm^3$, respectively. Their water contents are 21.0% and 20.5%. The coefficient of uniformity U and coefficient of curvature C obtained from sieve and hydrometer analysis are 125 and 0.42, which mean generally not well graded. On the soil classification by USCS, SM(silty sand or silt-sand mixed soil)is a Key soil, but it seems to be not good for fill material. From the standard proctor test are resulted $1.40{\pm}0.065g/cm^3$ for the unit weight(${\rho}$) in the nature and $1.88{\pm}0.049g/cm^3$ for the optimum proctor unit weight(${\rho}pr$) each. With this to say, it is necessary more powerful compaction work at earth filling, with which this soil reachs enough the ${\rho}pr$, and more earth.

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Effect of Medium Composition and Volume on Rooting and Growth of Cuttings of Rosa hybrida L. 'Red Sandra' and 'Little Marble' (배지의 종류와 부피가 절화 장미 'Red Sandra'와 'Little Marble' 삽목시 발근 및 생장에 미치는 영향)

  • Jeong, Jong-Woon;Kim, Gyeong-Hee;Hwang, Seung-Jae;Park, Su-Min;Jeong, Byoung-Ryong
    • Journal of Bio-Environment Control
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    • v.16 no.4
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    • pp.309-313
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    • 2007
  • Experiments were conducted to measure rooting and growth of rose cuttings as affected by medium composition and volume. Rosa hybrida 'Red Sandra' and 'Little Marble' were used as test plants. For medium composition test, rockwool, phenolic foam, perlite, vermiculite, peatmoss, coir and a commercial medium (Tosilee medium) were applied in single or mixed forms on the propagation bed with fog (200 sec./5 min.) installed to control the humidification time. 'Red Sandra' and 'Little Marble' cuttings were planted in 16-cell plastic pots and 72-cell plug trays, respectively. For the medium volume test, 72-cell plug trays and 16-cell or 9-cell plastic pots were used. Cuttings with an uniform node with a five-leaflet leaf was soaked in a $500mg{\cdot}L^{-1}$ IBA solution for 30 sec. A fogging system installed on the propagation bed was used for (100 sec./5 min.). Rockwool 1 : peatmoss 1 (v/v) was the most effective on growth and rooting for both cultivars and high volume of Tosilee medium and rockwool were most effective media far both cultivars.

Manufacturing and Mechanical Properties of Epoxy Fibers Spinning using Anhydride and Amine Hardeners (산 무수물계 및 아민계 경화제를 이용한 열경화성 에폭시 섬유 제조 및 물성)

  • Shin, Pyeong-Su;Kim, Jong-Hyun;Park, Ha-Seung;Baek, Yeong-Min;Kwon, Dong-Jun;Park, Joung-Man
    • Composites Research
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    • v.29 no.6
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    • pp.408-413
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    • 2016
  • Commonly-used polymers are manufactured as versatile forms. Furthermore, continuous polymer fibers are recently manufactured using nylon or aramid fiber. One of common epoxy was also used to make polymer fibers. Bisphenol-A type was used as base epoxy whereas amine and anhydride were used as hardeners. Epoxy fibers was cured by stepping up the temperature to maintain the shape of epoxy fiber. Surface energy was measured to confirm the degree of interfacial adhesion by modified static contact angle method. After mechanical properties were measured via fiber tensile test, the evaluation of fiber fracture was proceeded. Tensile strength of epoxy fiber using amine type hardener was higher as 138 MPa than anhydride case as 70 MPa. Fractured surface exhibited different failure patterns at the cross-section.

Characterization of Bovine Brucellosis in Korean Native Cattle by Means of Immunohistochemistry and Proteomics (면역조직 화학법 및 단백질체 변화 분석을 통한 한우에서 발생한 브루셀라증의 특성)

  • Jang, Seong-Jun;Do, Sun-Hee;Ki, Mi-Ran;Hong, Il-Hwa;Park, Jin-Kyu;Cho, Yu-Jeong;Park, Sang-Joon;Kim, Tae-Hwan;Kwak, Dong-Mi;Jeong, Kyu-Shik
    • Journal of Life Science
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    • v.20 no.2
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    • pp.153-160
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    • 2010
  • This study was conducted to examine the utilization of immunohistochemistry using the bovine anti-brucella immunoglobulin G (IgG) antibody in the diagnosis of brucellosis and to develop a functional biomarker relation for the progress of the disease. Anti-brucella IgG antibody was purified from the affected bovine serum using an affinity chromatography. We performed our investigation on 17 cases of brucellosis and 19 control cases with negative Rose-Bengal test results. Our purified anti-brucella IgG antibody showed a positive immunoreactivity in cytoplasmic hepatocytes of the centrilobular region, and glomeruli and tubular epithelium of the kidney. The protein pattern of the affected liver versus control was analyzed by two-dimensional electrophoresis, showing a different expression pattern of proteins between the two. Five protein spots were up-regulated and another were five down-regulated in the brucellosis liver. Significant upregulaton of catalase and 3-hydroxyacyl-CoA dehydrogenase might be due to a compensatory reaction in response to the endotoxic shock of brucella. In conclusion, the anti-brucella IgG antibody may be a good tool for discriminative diagnosis of the affected tissues and proteomics data suggest new target proteins underlying a possible pathogenic mechanism of brucellosis.

In Vitro Expression and Antibody Preparation of Rice black-streaked dwarf virus Coat Protein Gene (벼검은줄오갈병바이러스 외피단백질 유전자 단백질 발현과 항혈청 제작)

  • Lee, Bong Choon;Cho, Sang-Yun;Bae, Ju Young;Kim, Sang Min;Shin, Dong Bum;Kim, Sun Lim
    • Research in Plant Disease
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    • v.22 no.1
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    • pp.32-37
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    • 2016
  • In this work, major outer capsid protein (P10) encoded by genome segment S10 of Rice black-streaked dwarf virus (RBSDV) was expressed in Escherichia coli. Genomic dsRNA was extracted from RBSDV-miryang isolate infected rice plants. Based on the sequence of S10 (RBSDV-miryang, GenBank JX994211), a pair of S10 specific primers were designed and used to amplify the fragment encoding the N-part of P10. We amplified the partial gene (S10 1-834 nt) of RBSDV P10 (1-278 aa) by RT-PCR. Amplified RBSDV S10 (1-834 nt) was cloned into the expression vector pET32a (+). Recombinant RBSDV S10 (1-834 nt) was expressed in E. coli BL21(DE3) and purified by nickel-nitrilotriacetic acid (Ni-NTA) affinity column. We successfully obtained P10 partial protein of RBSDV and the purified protein was used to immunize rabbits. The resulting polyclonal antiserum specifically recognized RBSDV from infected plant in both Western blotting and enzyme-linked immunosorbent assay. In this study, we provide purified RBSDV P10 (1-278 aa), which would be good material for the serological study of RBSDV-miryang isolates.

A Study of Famous Traditional Kimchi in Pusan and Near Pusan Area (부산 및 부산근교의 명가김치 발굴을 위한 연구)

  • 문갑순;송영선;전영수
    • Korean journal of food and cookery science
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    • v.12 no.1
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    • pp.74-81
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    • 1996
  • Chinese cabbage Kimchi is a traditional fermented food and a numerous variety of Kimchies are produced in Korea. Most of Kimchis are produced on a small scale in the home for individual household use and recipes of Kimchis are deeply embedded in the individual cultures. Currently, however, factory-produced Kimchi is becoming popular by industrialization and changes of life style. This study was conducted to find out recipes of traditional Kimchis which are known delicious in Pusan and its environs and to develop a Kimchi with high quality. The characteristics of Kimchi recipes surveyed in Pusan and its environs are as follow: 1) Large amount of red pepper, garlic and anchovy sauce was used, which made Kimchi hot and spicy. 2) Extracts of dried anchovy or shrimp, or pear and onion juice was used to mix red pepper power. 3) Selection of good quality of Chinese cabbage and red pepper was very important step to determine quality of Kimchi. Furthermore, a numerous variety of submaterials added in Kimchi may also contribute to the high quality of Kimchi. 4) Salt concentration of Kimchi was around 2%, which was lower than it was generally known. Through this survey, it was suggested that maintaining low salt content of Chinese cabbage during salting make Kimchi crispy and juicy.

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