• Electric Engineers Magazine
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• v.265 no.9
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• pp.14-21
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• 2004

현재 국가간에 IEC를 통하여 국제적인 표준화를 진행 중에 있으나, 이러한 국가간의 표준화가 완료되기 이전이나 혹은 타국과 다른 특성의 제품을 제조 생산하는 경우에는 이와 관련된 내용을 자국의 기술 범위에서 언급을 하고 있는데 국내에서도 잘 알려진 NEMA VE 1-2002/CSA C22.2 NO. 126.1-02(METAL CABLE TRAY SYSTEMS)와 국내의 연구학문도 소개하여 전기계의 기술인들에게 참고 자료가 될 수 있도록 관련기준 위주로 정리하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.305-312
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• 2014

The current American Concrete Institute(ACI), Canadian Standard Associate(CSA) and CEB-FIP Model Code 2010 provisions on the shear strength of a simply supported deep beam suggest that deep beams should be designed using the strut-and-tie model. Although this is a useful methodology to design members in disturbed regions, the quality of the design is highly dependent on the truss model that designers create. However, Hong et al. derived the shear strength equations of reinforced concrete deep beams. This thesis investigates the validity of the current ACI, CSA and CEB-FIP code provisions on the shear strength of simply supported reinforced concrete deep beams by comparing them with the shear strength equations proposed by Hong et al. The comparison shows that all of these code provisions provide reasonable estimates on the shear strength of concrete deep beam members and the selection of an internal truss model plays an important role on the estimation of shear strength.

• Resources Recycling
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• v.32 no.6
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• pp.10-17
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• 2023

Calcium silicate cement (CSC) is an environmentally sustainable, low-carbon cement and has garnered significant attention in recent studies. However, the pre-curing step required to activate the carbon dioxide reaction and to handle the sample. This study aimed to examine the viability of extending the application of CSC without pre-curing by enhancing initial strength by mixing calcium sulfoaluminate (CSA) fast-hardening cement into CSC. The investigation assessed changes in compression strength and Q-XRD mineral characteristics concerning variations in the mixing ratio of CSC and CSA fast-hardening cement within a carbon dioxide atmosphere. The compressive strength results indicated that the 3-day and 7-day strengths were 14.18 MPa and 22.98 MPa, respectively, under the 50% CSC condition, meeting the type 1 cement KS standard. Mineral characteristics analysis revealed an increase in calcite mineral, a byproduct of the carbon dioxide reaction, contributing to strength enhancement. Even after seven days, substantial quantities of unreacted rankinitene and pseudowollastonite were observed, as well as dicalcium silicate and yeelimite, which are hydrated minerals. This observation was confirmed the possibility of strength improvement after 7 days.

• 전기의세계
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• v.38 no.12
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• pp.21-25
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• 1989

국내 최초로 첨단 전자세라믹스 제품인 ZnO Varistor의 국산화 개발에 성공하여, 정부로부터의 신기술 제품 보호를 받는 등 인정을 받았으며 그 이후로도 제품의 성능 및 신뢰성 향상등의 연구개발을 지속하여, 미국의 UL, 캐나다의 CSA등 외국의 유수 안전규격을 획득, 품질의 우수성을 입증받고 있을 뿐만 아니라 현재 국내의 광범위한 수요업체에의 납품은 물론, 미주와 구라파지역을 비롯하여, 홍콩, 싱가폴, 대만 등의 아시아 지역 등 많은 나라에 수출을 시작하고 있다. 아쉬운점이 있다면 국산화 개발이 이루어지자 일본 등의 기존 MAKER들이 가격을 대폭 인하함에 따라, 가격경쟁이 치열해져, 개발비 및 초기 설비투자비의 부담을 상대적으로 크게 안고 있는 국산개발 업체로서는 힘겨운 가격경쟁을 해야하는 등, 국산화 개발이라는 명분 외에는 기업의 투자효과를 크게 기대하기 어려운 실정이다. 따라서, 앞으로는 이러한 면이 정부 등에서 고려되어, 첨단기술 등 기술적 파급효과가 크거나 기술축적이 필요한 중요기술들의 국산화 개발시에는 보다 적극적인 정부의 지원시책과 수요업체의 관심이 있어야 할 것이다.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.544-558
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• 2017

The objective of this research is to investigate preservative efficacy for refractory species in field tests. The field tests were set up to evaluate the preservative performance of western hemlock and white spruce preservative-treated to the residential products group C and D of Canadian standard (CSA O80 Series-08) that have been developed for residential use in above-ground and ground-contact conditions, respectively. They were incised and pressure-treated with alkaline copper quaternary (ACQ) or copper azole (CA). Treated samples for the ground contact stake test and ground proximity test were installed in Jinju, Korea on November 2010 according to AWPA E7-09 and AWPA E18-06, respectively. Each sample has been annually assigned ratings for decay and termite attack, based on AWPA E7 grading system. After six years and five months of exposure, the untreated samples showed decay and particularly severe damage by termite attack but all the preservative-treated samples showed no decay. The results showed that the 5-mm penetration depths may be applicable for the treatment of refractory species. This paper discusses what to consider for the use of refractory species in Korean wood preservation industry from the penetration and retention points of view.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.947-953
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• 2005

Previous test results showed that the current ASTM(American Standard for Testing and Materials) grip adapter for GFRP(Glass Fiber Reinforced Polymer) rebar was not fully successful in developing the design tensile strength of GFRP rebars with reasonable accuracy. It is because the current ASTM grip adapter which is composed of a pair of rectangular metal blocks of which inner faces are grooved along the longitudinal direction does not take into account the various geometric characteristics of GFRP rebar such as surface treatment, shape of bar cross section as well as physical characteristics such as poisson effect, elastic modulus in the transverse direction and so on. The objective of this paper is to provide how to proportion the optimum diameter of inner groove in ASTM grip adapter to develop design tensile strength of GFRP rebar. The proportioning of inner groove in ASTM grip adapter is based on the force equilibrium of GFRP rebar between tensile capacity and minimum frictional resistance required along the grip adapter. The frictional resistance of grip adapter is calculated based on the compressive strain compatibility in radial direction induced by the difference between diameter of GFRP rebar and inner groove In ASTM grip. All testing procedures were made according to the CSA S806-02 recommendations. From the preliminary test results on round-type GFRP rebars, it was found that maximum tensile loads acquired under the same testing conditions is highly affected by the diameter of inner groove in ASTM grip adapter. The grip adapter with specific dimension proportioned by proposed method recorded the highest tensile strength among them.