• Journal of the Korea Concrete Institute
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• v.24 no.4
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• pp.445-452
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• 2012

In this study, experimental research was carried out to evaluate the structural performance of the reinforced concrete beam using strengthening materials (embedded FRP rod, metal fittings) in existing reinforced concrete buildings. Seven reinforced concrete beams comprised of retrofitted embedded FRP rod (BCR series), embedded FRP rod with metal fittings (BCR-AC series), and standard specimen (BSS) were constructed and tested under monotonic loading. Design parameters of test specimens were amount of embedded FRP rod and metal fittings. The test results showed that the maximum load carrying capacity of specimens with embedded FRP rod (BCR series) and embedded FRP rod with metal fittings (BCR-AC series) increased by 21~55% and 21~63%, respectively, in comparison with the standard specimen BSS. BCR series test specimens failed by the adhesion slip and concrete cover separation. BCR-AC series test specimens failed by the adhesion slip due to the confining effect of metal fittings.

• Journal of Power System Engineering
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• v.9 no.3
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• pp.71-78
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• 2005

A high-pressure hose includes rebar layers of the synthetic fiber such as nylon or a steel wire to control internal pressure. The hose assembly is manufactured through the swaging process to clamp the hose into the metal fittings. Usually, the hose behavior is affected by the resultant of the longitudinal and circumferential forces produced by the internal pressure. The rebar layers can appear the most ideal rebar effect when they are arranged to the same direction as the resultant force. The braid angle applied in the rebar layers is an important factor in determining ultimate burst pressure and overall hose life. Failure can occur on the contacted parts of a hose with the metal fittings under severe operating conditions such as high pressure and temperature of the inner fluid. In this paper, the mechanical behavior between the hose and the metal fittings during the swaging process and the stress variation characteristics of a high-pressure hose under a constant applied pressure are analyzed with respect to the braid angle of steel wire using the finite element method.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.805-810
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• 2002

An experimental study was carried out to evaluate the structural performance of new retrofitting technology using high performance carbon fiber bar and strengthening metal fittings. Experimental programs were accomplished to evaluate the structural performance of test specimens, such as load-displacement relationship, crack propagation, ductility, and strain of retrofitting materials etc.. Specimens(BCR2, BCR2-AF1) designed with the new retrofitting technology using high-performance carbon fiber bar and strengthening metal fittings showed much higher load-carrying capacity and ductility compared to specimens(BC1P, BC2P, BS30) designed with the conventional retrofitting method.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.242-253
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• 2020

Six ornamental metal quiver fittings were excavated from stone chamber No.1 of the ancient tombs of Jeongchon, Bokam-ri, Naju. The ornamental quiver fittings are metal, but the body of the quiver was made of organic material, so that it corroded and disappeared in the burial environment. The ornamental metal quiver fittings were made in pairs, and decorated one quiver according to the location they were found in and their forms. The ornamental metal quiver fitting can be divided into two types: A band style ornament (帶輪狀金具) which decorates the arrow pouch, and a board style ornament (板狀金具) which decorates the board connecting the waist belt. Two ornamental metal quiver fittings excavated from wooden coffin 2 of stone chamber No.1, were made in the band style, while the ornamental metal quiver fittings from southeast of stone chamber No.1 were identified as two boardstyle ornaments and two band-style ornaments for what was presumed to be belt loops. Material analysis of the ornamental metal quiver fittings shows that they are made of a gilt bronze plate attached to an iron plate, and the surface is marked with a speck of chisel to make lines and patterns. Chemical composition analysis (XRF) established that 24~40wt% Au and 50~93wt% Cu were detected on the gold surface, and it was confirmed that bronze corrosion had taken place on the gilt surface. SEM-EDS analysis of the gold plating layer identified a working line for glossing, and 7~9wt% Hg and an amalgam of gilt layers was detected, confirming the amalgam gilding. CT and FT-IR analysis established that the band style was double-layered with silk fabric under the iron plate, and there was also a lacquer piece underneath. The band-style ornaments have two layers of silk under the iron plate, along with lacquer pieces. Adding the fabric to the arrow pouch increases adhesion and decorative value. It is assumed that the lacquer pieces indicate that the surface of the lacquered arrow pouch had fallen together with the ornaments. On the other hand, the board-style ornaments have a thick layer of organic matter under the iron plate, but this is difficult to identify and appears to be a remnant of the quiver board. The characteristics of these ornamental metal quiver fittings were similar in Baekje, Silla, and Gaya cultures from the late 4th to the late 5th centuries, and enable us to identify the art of ancient gold craftwork at that time.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.335-336
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• 2008

Overhead transmission lines are mainly crossing mountainous area. They are easily affected in weathers like typhoon, strong wind, lightning, heavy rain, or heavy snow. Sometimes these weathers cause transmission line faults. A lightning flashover is most often fault. Nowadays lightning density in KOREA is growing high and lightning flashovers occur more often. A lightning flashover on transmission line is mostly cleared by momentary operation of a circuit breaker, so power failure happens rarely. However, when both circuits trip simultaneously due to the lightning flashovers on double circuit transmission line, short time power failure and voltage drop happen. KEPCO has used transmission line arresters to avoid double circuit simultaneous trip out since 2003. And transmission line arresters cannot be installed with KEPCO's present metal fittings, so various fittings have been used for each transmission line arrester manufacturer. This paper introduces development and standardization of arc-horn and metal fittings for transmission line arrester which can be used for both existing lines and new lines in KEPCO.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.13 no.4
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• pp.209-214
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• 1984

Friction factors and equivalent sand roughness of PVC pipe fittings have been studied by experiments in the Reynolds number range of $2,000\~70,000$. PVC pipe fittings studied are straight pipes, $90^{\circ}$ elbows and tees with 15, 25, and 40mm in norminal diameter, all manufactured in Korea with KS mark approval. Equivalent relative roughness of PVC pipes obtained lies between smooth pipe and 0.002. The study shows that equivalent sand roughness of PVC pipes increasses in proportion of the square root of pipe diameter , and can be approximately abtained by multiplying 4 to the root mean square value measured by metal surface roughness tester. Loss coefficient of PVC $90^{\circ}$ elbows decreases slowly with increasing Reynolds number. Loss coeffiicent of tees is a function of ratio of flow rates and Reynolds number.

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.4-17
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• 2021

This study analyzed 19 samples of harness fittings and pendants, which were excavated in Tomb No. 15 in Songhyeon-dong, Changnyeong. Harness fittings and pendants are used for ostentation, rather than practicality, and were excavated from ancient tombs in Gaya culture. So, they are considered artifacts that compare the production techniques and raw materials. This study aimed to examine the production techniques and provenience studies of Bihwa Gaya, which is estimated to be from the 5th to 6th centuries. According to the research, harness fittings were made of pure copper and were gilded with Au·Ag alloys on their surfaces. Hg was detected together and plated with a mercury amalgam method. As a result of the pendant (fish scales-pattern, oval and fish-tail shape), analysis showed that Fe in the background metal, Cu in the middle layer, and Au and Ag on the surface were the main components. The method of adhesion between Cu and Au·Ag gilded layers are plated by a mercury amalgamation method. So, it was identified by the gilt-iron·gold·bronze technique. Since the pendant (heart shaped) is found to be the main component of Fe in the background metal and Ag in the surface layer, the metal was made gilt-iron·silver technique. The background metal and gilding were additionally fixed using a rivet. The raw materials of 3 harnesses excavated from Changnyeong are plotted in zone 2 in the southern Korean Peninsula. And 16 harnesses were plotted in Chinese copper ore by Mabuchi Hishao in the Chinese Peninsula.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.81.2-81.2
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• 2010

Based on Yonsei Evolutionary Population Synthesis (YEPS), we have investigated the effect of horizontal branch stars (HBs) on the age-dating of simple stellar populations (SSPs). A detailed comparison of YEPS SSP with H_beta of M31 globular clusters (GCs) reveals (1) that the age dating without HB prescription gives ~5 Gyr younger ages for metal-poor M31 GCs, and (2) the age dating with HB prescription does not need any age gap between metal-poor and metal-rich GCs. This result is parallel to the well-known discrepancy in ages derived from integrated Balmer strengths and isochrone fittings of Milky Way GCs (MWGCs). Without a synthetic blue HB model, we cannot explain strong Balmer indices of metal-poor and old MWGCs. Our results suggest that the SSP model with well calibrated HBs should be used for the age-dating of SSPs to avoid a serious underestimation of ages due to the strong Balmer indices.

• Journal of environmental and Sanitary engineering
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• v.14 no.1
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• pp.1-10
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• 1999

This study was carried out to improve management of wasted home appliances and computers. The generation of wasted home appliances and computers in korea was estimated. Disassembling wasted home appliances and computers according to disassembly procedure, investigate fittings weight and disassembly time. To evaluate hazardous contaminants from televisions and computers, measure heavy metals by leaching test.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.58-67
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• 1998

A sectional analysis of sheet metal forming process with an arbitrary tool shape is proposed in the present work. To improve the numerical convergence in the conventional membrane sectional analysis, the Bending Energy Augmented Membrane (BEAM) elements had been developed. The BEAM elements particularly improve the stability and convergence of the finite element method for the case of deep drawing. In this work, the FERGUBON spline (C$^2$-continuous) was used to fit the deformed mesh to smooth the given curves and calculate the local curvature of the deformed sheet. The fittings of the deformed sheet and tool surface profile ensure the stability and the convergence of the finite element analysis of highly nonlinear stamping processes. A center floor section and front fender section are analyzed to show the accuracy and robustness of the approach. The results obtained by the proposed approach are compared with the available experimental data.