• 한국토양비료학회지
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• 제43권1호
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• pp.44-50
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• 2010

본 연구는 현재 유통 중에 있는 원예용 상토에 대해 이화학적 특성 및 안정도를 조사하여 상토이용의 최적화를 도모하기 위하여 수행하였다. 이를 위하여 12개 업체에서 생산하는 19 종류 원예용 상토를 수집하여 유럽표준분석법에 준해 상토의 이화학성을 분석하였다. 또한 이 결과를 이용하여 유럽에서 사용 중인 산소호흡률 측정방법에 따라 상토의 안정도를 평가하였다. 원예용 상토의 이화학성은 건물함량 39.33~69.00%, 수분함량 31.00~60.67%, 유기물함량 25.05~39.14%, 회분함량 60.86~74.95%, 실험실가밀도 227.38~391.20$g{\cdot}L^{-1}$ pH 4.75~6.10 EC 0.41~0.85 $dS{\cdot}m^{-1}$ T-N 0.19~1.29%, $P_2O_5$ 0.73~18.95 $mg{\cdot}L^{-1}$로 각각 조사되었다. 양이온 K, Mg, Ca, Na은 각각 49.72~306.74 $mg{\cdot}L^{-1}$, 9.97~91.17 $mg{\cdot}L^{-1}$, 6.90~283.32 $mg{\cdot}L^{-1}$, 80.68~295.83 $mg{\cdot}L^{-1}$의 범위를 나타내었다. 또한 가밀도 124.48~243.16 $kg{\cdot}m^{-3}$, 진밀도 2073.94~2249.99 $kg{\cdot}m^{-3}$, 총공극률 89.19~94.05%, 액상 57.14~78.35%, 기상 12.19~35.62%로 조사되었다. 원예용 상토의 산소호흡률은 2.03~5.63 mmol $O_2{\cdot}kg$ OM $hour^{-1}$로 선행연구를 통해 설정된 유기물질의 안정도 평가기준과 비교시 19점의 원예용 상토 중 17점의 상토에서 '매우 안정'의 단계로 조사되었으며, 나머지 2점의 상토에 대해서도 '안정' 단계로 평가되었다. 향후 상토의 산소호흡률을 이용한 안정도 평가를 통해 최적조건의 상토가 지속적으로 관리될 수 있을 것으로 판단된다.

• 한국환경농학회지
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• 제39권4호
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• pp.319-326
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• 2020

BACKGROUND: Measurement equipment was developed for inorganic nutrient concentration inside the hydroponic culture medium with several macro- and micro compositions, and applied for measuring the compositions of conventional medium. METHODS AND RESULTS: Before the equipment development, sonicator and heater were utilized to control temperature around of the module mixing with color reagents and target samples among the inorganic compositions. The measurement module and multi-sampler were also manufactured based on the COMS (Complementary Metal-Oxide Semiconductor) and installed inside the measurement equipment. Concentration of standard solution, value measured by the equipment, standard deviation or measured average value were used for estimating the accuracy and average recall of the equipment. Yamazaki solutions with EC of 0.5, 1.5, and 2.5 dS/m were offered to confirm the equipment accuracy and standard error. CONCLUSION: It was suggested that the developed equipment could be automatically applied for measurement with accuracy of over 96% and standard errors of less than 5% on 12 macro- and micro compositions such as a NO3-N, PO43- or Fe.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제6권5호
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• pp.477-486
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• 2000

본 논문은 SGML(Standard Generalized Markup Language) 문서를 포맷팅 처리하여 표현하기 위한 SGML 문서정보 표현 시스템의 설계 및 구현에 관한 것이다. 이를 위해 본 논문에서는 ISO/IEC에서 SGML 문서 포맷팅을 위해 정의한 모델인 DSSSL(Document Style Semantics and Specification Language)표준에 따라 시스템을 설게하였고, SGML 문서를 온라인으로 포맷팅 처리하는 시스템을 구현하였다. 본 시스템은 한글 처리를 지원하면서 임의의 DTD(Document Type Definition), SGML 문서, DSSSL 스타일 시트에 대한 파싱 기능을 가지며, 텍스트뿐만 아니라 표, 목록, 그림 등 다양한 명세 표현이 처리 가능한 포맷터를 포함한다. 이는 이 기종간에 포맷 정보를 포함한 SGML 문서 교환에 대한 사용자 욕구를 충족시킬 수 있으리라 보며, SGML 문서처리 환경 구축에 크게 기여하리라 본다.

• 한국생활과학회지
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• 제13권1호
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• pp.1-16
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• 2004

The purpose of this study was to examine the self-regulation in E-commerce business and review the major issues of self-regulation in several countries. This paper reviewed the legislation for the self regulation of APEC, OECD and EC, and introduced the regulation system for several countries, such as U.S. U.K and Japan. Also, we analyzed the current issues and problems of self-regulation in Korea and tried to suggest the future direction. There were three different regulations such as market forces, government regulation and self-regulation and the model of self-regulations were shaped in various types. Even though the government made the standard regulations for business sector but it was impossible to direct individual firms and their compliance of those regulations. To compensate the government regulation, the self regulation with low cost is needed and also two kinds of regulations has to be unified to enhance the regulation system in E-commerce. Industries should participate for the regulation voluntarily and consumers must give an award of legislation for self-regulation to motivate the self-regulations of industries.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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• pp.686-693
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• 1998

Prestressed Concrete Cylinder Pipe(PCCP) is used in water transmission pipeline of the Great Man-made River Project(GMR Project). In domestic area, PCCP is used for water cooling systems of Uljin and Youngkwang nuclear power plants. In abroad, especially in the United States and Canada PCCP supplies virtually every metropolitan area with raw and treated water. Compared with other pipe types, PCCP manufacturing cost is dear. But total cost can be considered as economical due to low installation and maintenance cost. Previously, the designs of PCCP were generally determined from one of two appendices in American Water Works Association(AWWA)standard C301 which provided two design methods-cubic parabola design method and stress analysis design method. In 1992, the design procedure for PCCP expanded from two alternatives to the most huge and complex AWWA standard C304. Because C304is so large, it takes too much time for the engineer to read and understand the design concepts and procedures. In this paper, the AWWA C304 design procedures are segmented into simple, understandable sections and concepts and explained. Each section or concepts is compared to the previous design procedure to highlight the revisions and reasons for them. Also the PCCP design program was developed and the design program results are compared with the calculations of the GMR project design consultant.

• 한국해양공학회지
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• 제15권1호
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• pp.98-103
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• 2001

This paper is conducted to compare the seismic design standard of a bridge column such as the Korean Bridge Design Standard(KBDS), EC 8, NZS 3101 and ATC 32. The KBDS adopted the seismic design requirements in 1992. The earthquake magnitude in Korea is compared with those in the west coast of the USA. It may be said that the current seismic design requirements of the KBDS provides design results, that are too conservative especially for transverse reinforcement details and amounts in reinforced concrete columns. This fact usually creates construction problems in concrete casting, due to congestion of transverse reinforcement. Furthermore, the effective stiffness; $I_{eff}$ depends on both the axial load P/$A_gF_{ck}$ and the longitudinal reinforcement ratio $A_{st}/A_g, so it is the conservative to use the effective stiffness I$_{eff}$ than the gross section stiffness Ig. Seismic design for the transverse reinforcement content of the concrete column was analyzed and considered to have an extreme-fiber compression strain, response modification factor, axial load and effective stiffness etc.c.

• Elastomers and Composites
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• 제59권1호
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• pp.34-41
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• 2024

In this study, the effects of the type and content of silica on the mechanical and tear properties of chloroprene rubber (CR), which is mainly used as a jacket material for mining cables, were studied. The crosslinking density (ΔM) and reinforcing factor (α_f) defined using cure characteristics increased with increasing silica content, whereas the cure rate decreased. The hardness, tensile strength, and modulus of the CR compounds increased depending on the silica content and structural development. The reinforcing behavior of the silica-filled CR compounds according to the silica type and content showed the best fit with the Thomas equation of the predictive model. Tear strength was evaluated using two standard test methods, ASTM D470 and DIN VDE 0472-613, and the results were compared. The tear strength increased as the silica content increased, regardless of the test method, and the different tear strengths obtained by the two standard test methods showed a linear relationship with each other, indicating a high correlation.

• 한국전자거래학회지
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• 제7권3호
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• pp.61-73
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• 2002

Product catalog information is the most important factor to make customers purchase the product for various B2B or B2C businesses provided on the Internet. As catalog information differs from company by company, it cannot provide common criteria standard to customers to make decisions. Therefore, it is necessary to develop a platform independent system, which integrates incompatible data from each company' catalogs and manages its database. This paper describes the integrated E-catalog system made up DB module, catalog management module, and interface module. This system allows customers to view standardized product catalog information from different companies with real -time updates, and also provides extensibility, flexibility, and interoperability for the effective E-Business management.

• 식물병과 농업
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• 제1권1호
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• pp.14-18
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• 1995

This study was carried out to investigate effect of transplanting method, environmental factor, and fertilizing level on occurrence of Pseudomonas glumae in south-west coastal area of Chonnam province. Occurrence in filed began after heading and increased gradually during 3-4 weeks. Occurrence of this disease was great at daily minimum temperature of 23-$25^{\circ}C$ and series of rainfall during early and mid. August Degree of infection by fertilization of nitrogen and by transplanting fertilizing level of 50% than standard fertilization of nitrogen and by transplanting method was greater machine-transplanting than hand-transplanting. Rate of degradation was 6.5% in case of 10% of infected panicle, 14.5% in 30%, 22% in 50% and 35.9% in 70%. We can reduce occurrence of this disease by sawing non -infected seed and balanced fertilizing in cultural practice and applying oryza 4kg/a in early transplanting or Kasugamin EC and Allta in heading stage.

• 전기학회논문지
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• 제58권7호
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• pp.1356-1362
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• 2009

IEC 61400-25(Communications for monitoring and control of wind power plants) is established as a international standard by IEC TC 88 in 2007 with the growth of the wind power industry. In this paper, MMS service which is defined in lEC 61400-25 part 4 is implemented, and the wind power generator is objectified by using the VMD of MMS service. We also implemented MMS communication system between the wind power generator and the local control center using the proposed VMD. The performance of the developed MMS communication system is verified through the XML based user interface on the web browser.