• Title/Summary/Keyword: JIS

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A Comparative Study of Ophthalmic Spectacle Lenses Standards (시력보정용 안경렌즈의 규격에 관한 비교 고찰)

  • Yu, Dong-Sik;Moon, Byeong-Yeon;Son, Jeong-Sik
    • Journal of Korean Ophthalmic Optics Society
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    • v.9 no.2
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    • pp.397-415
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    • 2004
  • This study surveyed differences among KS, ISO, JIS and ANSI ophthalmic spectacle lenses standards. These standards applied to several lenses that were in common currency and we checked over problems and improvements in KS. KS corresponded to ISO, for the most part, and ANSI, partly. But terms, definitions, progressive power lenses standards, UV transmittance and base curves clauses did not exist in KS. There was no differences between nominal data and actual data in important clauses estimation-minimum requirements on refractive power, tolerances on the size of lenses, material and surface quality. But tolerances of thickness, base curves, UV and visible transmittance values were not existing, there were differences among several ophthalmic spectacle lenses in the test of these clauses. These requirements will be needed for better and more comfortable vision.

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The Spatial Restructuring and Changes of Locational Pattern of Auto Parts Industry in Korea (자동차 부품산업의 공간적 재구조화와 입지 패턴 변화)

  • Kim, Tae-Whan
    • Journal of the Korean Geographical Society
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    • v.42 no.3 s.120
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    • pp.434-452
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    • 2007
  • The globalization of the economy has strengthened competition in all industries. Facing an intensely competitive environment, the firm's choice of location is one of the most important strategies in enhancing its competitiveness. This paper aims to examine the locational changes and the spatial restructuring of suppliers firm with regard to modularization and customer diversification which result from the process of assembler's restructuring after the financial crisis. Some experimental findings which have been identified throughout this study can be summarized as follows: First, a number of suppliers has been located in the southern Seoul metropolitan area and northern Chungcheong area. And Hyundai's suppliers has been enlarged in the Seoul metropolitan area and Kia's in the Southeastern area. Second, suppliers who transact with several assemblers(network trade) tend to be more dispersed, but dedicated(exclusive) suppliers are more concentrated on assembly plants. Also it was confirmed that 'JIS(Just In Sequence)' system which is more detailed than 'JIT(Just In Time)'system has been used. Third, it was Prominent that suppliers are internalizing in order to reach economies of scale compare to assemblers are externalizing.

Braking Force Test Evaluation Dynamometer Development of Vehicle (차량용 브레이크 제동력 평가 다이나모미터 개발)

  • Kwon, Byeong-Heon;Yoon, Pil-Hwon;Lee, Seon-Bong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.5
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    • pp.56-65
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    • 2019
  • Recently, automobiles have been developed for safety and environmental reasons. Particularly, awareness of automobile safety is changing significantly. As a result, safety systems developed by ADAS have emerged. However, the period of mass production through ADAS development and test evaluation is long. Therefore, in this paper, we develop a brake dynamometer to shorten the time required for ADAS development and test evaluation. In addition, the developed brake dynamometer satisfies the international standard JIS D-0210, and the user can evaluate the braking force by selecting test conditions and test method for each mode of ADAS. We use the ACC, LKAS, and AEB scenarios proposed in previous studies to verify the reliability of the developed brake dynamometer. The developed brake dynamometer was verified by comparing the test values and the calculated values using theoretical formulas of the proposed ADAS mode based on previous studies. In addition, it is expected that the performance evaluation of brake parts for each ADAS mode will be possible in an environment where the vehicle test of ADAS is not possible in the future.

Comparative Analysis of International and Domestic Safety Assessment Criteria for the Powered-Scooter and the Electric-Wheelchair (전동휠체어 및 의료용스쿠터의 국내·외 안전성 평가기준 비교 분석 연구)

  • Jun, Sung Chul;Seo, Jeong Hee;Lim, Hee Chul;Lee, Chang Hyung;Shin, Young Il;Jung, Duk Young
    • 재활복지
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    • v.16 no.3
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    • pp.421-437
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    • 2012
  • The goal of this study is to provide the basic information for improvement of domestic standards on the powered scooter and the electric wheelchair considering using environments in the nation. The international standards and domestic standards have been analyzed and compared, in order to propose improved domestic standards. Based on the research, the items and standards for general and functional recommendations, electric features, and other suggestions have been reexamined so that the improvements on test item and standards have been identified, corrected, and summarized including max. speed, brake system, lights and so on. We have been preparing the reference data for the improvement of standards on the powered scooter and the electric wheelchair through the comparison & analysis on the international and domestic standards.

Investigation of Changes in Structural Characteristics and Chemical Composition after Heat Treatment Process of JIS-SUJ2 Bearing Steel (JIS-SUJ2 베어링강의 열처리 이후 표면 및 심부에서 나타나는 구조적, 화학적 물성 변화)

  • Donghee Lee;Kyun Taek Cho;Hyeonmin Yim;Seung-Hwan Oh;Tae Bum Kim;Woo-Byoung Kim
    • Korean Journal of Materials Research
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    • v.33 no.12
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    • pp.558-564
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    • 2023
  • In this study, we designed and manufactured a large angular contact ball bearing (LACBB) with low deformation using JIS-SUJ2 steel and analyzed changes in its structural characteristics and chemical composition upon heat treatment. The bearing was produced by hot forging and heat treatment including a quenching and tempering (Q/T) process, and its properties were analyzed using 4 mm thick specimens. A difference in the size distribution of the carbide in the outer and inner parts of the bearing was observed and it was confirmed that large and non-uniform carbide was distributed in the inner part of the bearing. After heat treatment, the hardness value of the outer part increased from 13.4 HRC to 61 HRC and the inner part increased from 8.0 HRC to 59.7 HRC. As a result of X-ray diffraction (XRD) measurements, the volume fraction of the retained austenite contained in the outer part was calculated to be 3.5~4.8 % and the inner part was calculated to be 3.6~5.0 %. The surface chemical composition and the content of chemical bonds were quantified through X-ray photoelectron spectroscopy (XPS), and a decrease in C=C bonds and an increase in Fe-C bonds were confirmed.

Comparison of Cement Strength According to Standard Units (각국 표준 규격에 따른 시멘트 강도 비교실험)

  • 김남호;정재동;이한봉
    • Proceedings of the Korea Concrete Institute Conference
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    • 1990.04a
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    • pp.20-23
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    • 1990
  • In order to evaluate the difference of testing results in the standards on the compressive strength of various countries, we have compared the testing results of the compressive and flexural strength, one of the most important properties of cement, obtained on the various standards(KS, JIS, BS, ASTM) and the statistical method was used to evaluate the results.

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Formation of Fe-Al Intermetallic Compound in GMAW Overlay (GMAW오버레이의 Fe-Al 금속간화합물의 형성)

  • 김병수;박경채;조상흠
    • Proceedings of the KWS Conference
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    • 2003.11a
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    • pp.240-241
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    • 2003
  • The iron aluminides have been among the most widely studied intermetallics because of their low cost, low density, good wear resistance, ease of fabrication and resistance to oxidation and corrosion. In this study, weld overlay was performed with JIS-YGW11 and A14043 wire on the base metal.

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안전표지의 통일과 ISO 규격화 동향

  • Korea Industrial Health Association
    • The Safety technology
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    • no.42
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    • pp.8-13
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    • 2001
  • 회사에서 사용하는 안전표지는 여러가지 형태로 의미도 다르다. 이에 따라 작업자가 회사를 변경할 때마다 새로운 안전표지를 만나게 되는데 이 때 잘못 판단하거나 잘못 조작으로 위험을 초래하는 사례가 빈번하다. 따라서 안전표지의 규격화를 통한 기업 개선사례와 ISO.JIS규격화 동향에 대해 살펴보도록 하겠다.

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Introduction of the Rapid Analysis Method for PCBs in Insulating Oils and Its Comparison Study to the Analysis Method in Korea

  • Hong, Jang-Ho;Takahashi, Tomohumi;Ishizaka, Takahiro;Toita, Hideki;Min, Byung-Yoon;Honda, Katsuhisa
    • Environmental Engineering Research
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    • v.16 no.1
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    • pp.11-18
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    • 2011
  • The aim of this research was to introduce a new rapid analysis method (heating of the multi-layer silica gel column/alumina column) for polychlorinated biphenyls in insulating oils, and to compare our new method with the analytical method currently used in Korea. The entire pretreatment procedure was completed within 2 hr, using about only 20 mL of solvents via our rapid analytical method. Furthermore, the pretreatment procedure can always be uniformly performed, regardless of oil type (JIS 1~JIS 7 and KS 1~KS 7). The recovery rates were more than 89%, with relative standard deviations below 6.0%. In conclusion, this rapid analytical method could reduce the pretreatment time and solvent usage by 1/10 and between 1/25 and 1/50, respectively, compared to analytical method currently used in Korea.