• International Journal of Highway Engineering
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• v.19 no.3
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• pp.1-10
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• 2017

PURPOSES : This paper focuses on strength development according to the mix design with cement type and mineral admixture from laboratory and field tests in cool weather. METHODS : Two methods evaluated the mix design of concrete pavement in cool weather. Firstly, laboratory tests including slump, air contents, setting time, strength, maturity, and freezing-thawing test were conducted. Three alternatives were selected based on the tests. Secondly, a field test was conducted and the optimum mix design in cool weather was suggested. RESULTS : It is an evident from the laboratory test that a mix with type III cement showed better performance than the one with type I cement. There was a delay in strength development of a mix with mineral admixture compared to mix design without any mineral admixture. In the field test, type III cement+flyash 20% mix design proved the best performance. CONCLUSIONS : For concrete pavement in cool weather, mix design using type III cement could overcome the strength delay due to mineral admixture. Moreover, it is possible to make sure of durability of pavement. Therefore, strength and durability problems due to cool weather would decrease.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.6
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• pp.1193-1200
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• 2014

Edwardsiella tarda, Streptococcus iniae and S. parauberis are main bacterial pathogens in aquaculture farms of olive flounder, Paralichthys olivaceus. We have discussed the efficacy and safety of 3 type-combined vaccines (A: S. iniae 1mg + S. parauberis 1mg + E. tarda 1mg, B: S. iniae 1mg + S. parauberis 1mg + E. tarda 0.5mg, C: S. iniae 1.5mg + S. parauberis 1.5mg + E. tarda 1mg) through intraperitoneal injections in olive flounder. None of the vaccines gave rise to any signigicant side effects on histopathology and blood chemistry. The antibody titers and lysozyme activities of A type were higher than those of B, C and control. Four weeks after vaccination, RPS (relative percent survival rates) was 62.5~75% (A type), 50~66.7% (B type) and 55.6~62.5% (C type) respectively. As the results, the combined vaccines are possible to prevent edwardsiellosis and streptococcosis, and A type : S. iniae 1mg + S. parauberis 1mg + E. tarda 1mg, is the most effective out of them.

• Food Science and Preservation
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• v.10 no.1
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• pp.23-27
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• 2003

This study was conducted to develop the corrugated fiberboard box which is suitable to pre-cooling and low temperature distribution of chinese cabbage Consider from a cooling performance viewpoint, the folding type box with 5.4% vent hole ratio was most efficient for fast cooling and even temperature distribution in the packaging box. At the end of storage periods, the compressive strength of the folding type box was less than the bliss type box. However, the compressive strength of the folding type box after storage was higher than required safety compressive strength for long term storage. So the folding type box was considered to have no problems toy practical use. The shelf-life of the chinese cabbage packaged with the developed box was 6∼7 days which was 2∼3 days longer than usual packaging.

• Journal of Technology Innovation
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• v.2 no.1
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• pp.219-241
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• 1994

This paper presents the results of an empirical study on the relationship between the type of new product idea sources and the rate of success of new product development and commercialization in Korean industries. The sample was taken from various Korean industries including telecommunication, electronics, chemical, machinery, textile, etc. and composed of 45 failure and 73 success cases. The findings are not much different from those of previous studies done in the developed countries, but show some typical characteristics of new product development activities and the idea sources, information acquisition methods, type of information , incentives for idea generation, etc. of the firms in developing country like Korea. Especially the survival rate curve and the accumulative investment curve from the idea generation to commercialization phase show a little different behavior from the previous study, which also reflect the manpower, duration of each phase of the new product development process in the Korean firms.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.88-94
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• 2022

The relationship between sound and vision was experimentally confirmed by physicist Ernst Florens Friedrich Chladni as early as the 18th century and formally entered into systematic research. With the development of emerging media technology, sound reactive type visual content is not limited to a single visual interaction based on the vibration of sound, and its visual content shows a diversified and scalable development trend according to different purposes in many fields. This study analyzes the development and changes of sound visual art contents from early stage to modernization, and analyzes the development characteristic of sound visual art content in different fields and scene environments influence by interactive media, new media technologies and devices by means of case analysis. Through this research, it is expected that the sound reactive type visual art content can continue to develop and extend in the existing fields, while explore the scalability of the application of sound reactive type visual art content in more fields.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.741-744
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• 2003

In this study, the influence of chemical admixture on early strength development of concrete is discussed. According to the results, fluidity with variation of kinds of chemical admixture is lower in the case of acceleration type than in the case of normal type. Setting time of naphthalene acceleration type is shortened by I hour, and that of melamine is nearly same, but that of polycarbonic acid is somewhat retarded in comparison with that of naphthalene normal type. Early compressive strength gains 5MPa in about 18hours regardless of the kinds of chemical admixture. But as time elapses, compressive strength is higher in order of polycarbonic acid, naphthalene and melamine type. The relativity between compressive strength and the rebound value of P-type schmidt hammer is also favorable at early age, and compressive strength of 5MPa is estimated at the rebound value of 22.

• Journal of electromagnetic engineering and science
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• v.6 no.2
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• pp.110-116
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• 2006

A reflective array type surface acoustic wave(SAW) dispersive delay line(DDL) with high time-bandwidth at the V/UHF-band is designed and fabricated for compressive receiver applications. This type of the SAW DDL has the properties of the relative bandwidth of 20 %, the time delay of 49.89 usec, the insertion loss of 38.5 dB and the side lobe rejection of 39 dB. In comparison with a commercial SAW DDL, the insertion loss, amplitude ripple and side lobe rejection are improved by $1.5dB{\pm}0.6dB$ and 4 dB respectively. Using the fabricated SAW DDL, the prototype of the compressive receiver is developed. It is composed of RF converter, fast tunable LO, chirp LO, A/D converter, signal processing unit and control unit. This prototype system shows a fine frequency resolution of below 30 kHz with high scan rate.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.347-352
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• 2002

The Cut off-type progressive die for U-bending production part is a very specific division. This study reveals the sheet metal forming process with multi-forming die by Center Carrier type feeding system. Through the FEM simulation by DEFORM, it was accepted to u-bending process as the first performance to design of strip process layout. The next process of die development was studied according to sequence of die development, i.e. die structure, machining condition for die making, die materials, heat treatment of die components, know-how and so on. The feature of this study is the die development of scrapless progressive die of multi-stage through the Modeling on the I-DEAS program, components drawing on the Auto-Lisp, CAD/CAM application, ordinary machine tool operating and revision by tryout.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2002.11a
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• pp.131-136
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• 2002

The purpose of this study is to analyze the characteristic of street markets in land development district, Dae-gu(Sung-su, Yeoung-san and Si-gy Land development districts). The result of this study is as follows, Street markets are located between detached housing estates and cooperative housing estates. Street markets are classified as private road type, linear street type and mixed type, The influential area of street markets is extended form inside of detached housing estates to arterial road. The vitality of street markets is explained by the scale of dwelling area, road system and variety of function.

• Korean Journal of Medicinal Crop Science
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• v.28 no.6
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• pp.471-480
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• 2020

Background: The roots of Cirsium japonicum var. ussuriense (RCJ) have been used as traditional medicine in Korea for hematuria and hematemesis. These extracts exert anti-oxidative and anti-inflammatory effects by scavenging for free radical and regulating the inflammatory response. However, the effect of RCJ on rheumatoid arthritis (RA) has not been elucidated. Thus, we evaluated the water extract of RCJ (WRCJ) using type II collagen-induced RA models. Methods and Results: RA was induced by immunization with type II collagen. All experimental materials were orally administered daily for three weeks. The positive control group was administered with 0.2 mg/kg methotrexate (n = 7), while the experimental group was administered with WRCJ (100 or 500 mg/kg, n = 7). Serum levels of TNF-alpha, Interleukin 6 (IL-6), and type II collagen IgG (CII) were measured using ELISA. Administration of 500 mg/kg WRCJ decreased the levels of TNF-alpha, IL-6, and CII. Moreover, WRCJ treatment diminished swelling of hind legs and infiltration of inflammatory cells in RA models' synovial membrane. Conclusions: These results indicate that WRCJ could improve RA, reduce inflammatory indicators and synovial inflammation. However, further experiments are required to determine how WRCJ can influence the signal transduction pathway in RA.