• Journal of Korean Vacuum Science & Technology
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• v.4 no.2
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• pp.44-46
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• 2000

Near-field photocurrent experiments were performed for GaAs/AIGaAs MQWs at room temperature. Heavy hole and light hole related peaks are clearly resolved even under extremely low power of near-field excitation. By scanning laterally 2 $\mu\textrm{m}$${\times}$2 $\mu\textrm{m}$ area on the surface, minority carrier diffusion process in the well region was qualitatively studied.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.77-78
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• 2022

This study compared the fire safety standards for windows of Korea, the U.S. and Japan to prevent fire expansion through exterior wall openings, and conducted experiments using PVC and aluminum window frames, which are widely used in Korea.The experiment is KS F 2845 which combines frames of the same thickness and area with single-window form and 1 hour fire resistance glass with 8T thickness. Experiments showed that the PVC window was about 9 minutes and the aluminum window was about 26 minutes. However, in Korea, there are no test standards for windows installed at the opening of the exterior wall. In addition, fire safety standards for windows shall be established along with the designation of fire prevention zones.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.54-55
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• 2021

This study compared the fire safety standards for windows of Korea, the U.S. and Japan to prevent fire expansion through exterior wall openings, and conducted experiments using PVC and aluminum window frames, which are widely used in Korea.The experiment is KS F 2845 which combines frames of the same thickness and area with single-window form and 1 hour fire resistance glass with 8T thickness. Experiments showed that the PVC window was about 9 minutes and the aluminum window was about 26 minutes. However, in Korea, there are no test standards for windows installed at the opening of the exterior wall. In addition, fire safety standards for windows shall be established along with the designation of fire prevention zones.

• Korea Trade Review
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• v.47 no.3
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• pp.129-139
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• 2022

Ethical issues in international trade will first need to be resolved through applicable public methods. However, considering that there is a party who produced and manufactured the goods, that is, a seller, and a buyer who purchased the goods, the area of the public law is now a matter of private law. Since the CISG does not mention the term 'ethics' in the full text, an ethical consideration is needed to interpret using existing provisions. In addition, a review of the validity, explicit and implied conditions, trade usages, or established practices between the parties through the CISG shows that ethical issues between the trading parties subject to the CISG may constitute part of the sales contract. Ethical hardship in the process of implementing the contract can also be seen as a impediment in the CISG. However, the safe way for a party to avoid disputes is to explicitly insert a contract clause incorporating ethical standards in the contract or add related terms and conditions and codes of ethics.

• Korean Journal of Childcare and Education
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• v.10 no.6
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• pp.223-241
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• 2014

The objective of this study was to plan a direction for the connection of the area of inquiry in daily life between infants and young children in Korea based on the analysis of the early learning standards for infants aged 0~2, and young children aged 3~4/5 in 17 different states in America. The problem of the study is as follows: What is the content area of cognitive development, science and mathematics of early learning standards regarding age? The data used in this study was collected from a total of 17 states in America in which 12 states classify infants and young children as aged 0~2 and 3~4/5 respectively and 5 states do not classify the age groups. The results obtained from the analysis of the given issues are as follows. First, in the case of the five states that showed the group aged 0~4/5, the contents related to the area of inquiry in daily life of the early learning standards were included in the mathematics and science and a part of these contents were also included in cognitive developments. In the case of the 12 states that classified the groups aged 0~2 and 3~4/5 respectively, the group aged 0~2 included cognitive developments and the group aged 3~4/5 includes mathematics and science. Second, the contents related to the area of inquiry in daily life of the early learning standards in the five states that showed the single group aged 0~4/5 include the contents in order of scientific idea, biology, physics, and the earth and space. In the 12 states that classify different age groups. Third, in the case of the states that separate age groups, the group aged 0~2 include the contents of number and operation, geometry and space while the group aged 3~4/5 include the contents of number and operations, geometry and space, and measurement. The implications of this study was that it is necessary to take into account the linking between development and characteristics of the subjects.

• Journal of The Korea Institute of Healthcare Architecture
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• v.23 no.1
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• pp.15-24
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• 2017

Purpose: Korea is expected to enter an aged society in 2018 and then a super-aged society in early 2025. The country's aging is progressing faster than any other country in the world. However, the foundation of the elderly friendly industry is weak, and measures at the government level are urgently needed. Especially, housing problems of the elderly are one of the most urgent measures to be taken. Korea does not have the minimum residential area standard for the elderly, and the current general minimum residential area standard is based on the survey of the housing situation without scientific evidence. Therefore, both standards need to be revised as soon as possible based on scientific evidence. Methods: The minimum residential area standard has been calculated following Karl H. E. Kroemer's Min or Max design also being called as-single cut and dual cut theory- as the maximum population value and minimum population value theory of Ernest J. McCormick. Therefore there is a need for a formula made using a few key factors, such as corresponding dimension, practical dimension, clearance, spare dimension, integrated dimension. These elements can be defined and used as formulas to calculate minimum residential area standards. Results: Assuming the results of the spatial variability in this study showed that it is possible to raise the standard of living in a terms of sustainable minimum size for the young, old and all residents. Implications: The government should set a minimum residential area standard with scientific grounds and set up a policy improving the life of people who live in an needy residential environment.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.212-221
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• 2013

Objectives: Asbestos fibers are accumulated in negative pressure unit (NPU) or vacuum cleaner in asbestos removal. Failure of operation or poor use performance of the NPU or vacuum cleaner causes asbestos fibers to spread in the air. Asbestos contractors should have an NPU fitted with a HEPA , vacuum cleaner, decontamination area, respirators, wetting equipment, and differential pressure manometer to register with the Ministry of Employment and Labor. There should be performance criteria of equipment used in asbestos removal. But there are none such criteria used in asbestos removal. This study was performed to investigate international or national performance criteria of equipment used in asbestos removal. Methods: Regulations, approved code of practice, guidance and national standards of the UK, USA and Korea were reviewed. A survey was done to investigate the requirements for equipment used in asbestos removal in Korea. Results: Air flow of NPUs used in Korea usually covers from$500m^3/h$ to over $3000m^3/h$. Some requirements for NPUs used in Korea were missing compared to the requirements of British standards for NPUs. All NPUs have different missing requirements. The UK also has separate British standard for leak tests for NPUs. Highly hazardous class vacuum cleaners should be used in asbestos removal in the UK. It has national standards on the operation of vacuum cleaners used in asbestos removal. There is only a certification system for less than 2.5kw rated voltage vacuum cleaners for home use in Korea. Powered (-assisted) respirators with mask are recommended in asbestos removal. Type 5 coveralls should be used in asbestos removal in the UK. There are international standards for requirements and leak tests of type 5 coveralls. A manometer for measuring differential pressure is needed in asbestos removal. The manometer's measuring range should cover less than ${\pm}125$ Pa and the gradation of manometer should be less than 2.5 Pa. The definition of decontamination area should be corrected. Installation of airlock and minimum area should be considered in decontamination area. Conclusions: Equipment should be used in asbestos removal proper performance and no leaks. There should be a certification system for equipment used in asbestos removal. This study can help to a certification system for equipment used in asbestos removal in Korea.

• Korean Journal of Optics and Photonics
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• v.32 no.6
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• pp.314-322
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• 2021

A reflecting telescope consists of a concave primary mirror and a convex secondary mirror. The primary mirror is easy to measure, because it converges the beam from an interferometer, while the secondary mirror diverges the beam and so is not easy to measure, even though it is smaller than the primary mirror. In addition, the Korsch-type telescope uses the central area of the secondary mirror, so that the entire area of the secondary mirror needs to be measured, which the classical Hindle test cannot do. In this paper, we propose a double-stitching method that combines two separate area measurements: the annular area, measured using the Hindle stitching method, and the central area, measured using a spherical wave from the interferometer. We test the surface error of a convex asphere that is 202 mm in diameter, with 499 mm for its radius of curvature and -4.613 for its conic constant. The surface error is calculated to be 19.5±1.3 nm rms, which is only 0.7 nm rms different from the commercial stitching interferometer, ASI. Also, the two results show a similar 45° astigmatism aberration. Therefore, our proposed method is found to be valuable for testing the whole area of a convex asphere.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.1
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• pp.46-53
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• 2000

Magnetostrictive sensors which can be used effectively to detect flaws in pipe were fabricated. The optimal conditions to obtain the maximum generation efficiency of the ultrasonic wave were established. In case of the used steel pipe the optimal magnetic field was $250{\sim}350Oe$ and the coil width of 15mm showed the best efficiency for generating a wave with the frequency of 180 kHz. In the best condition, the wave can propagate further than 50m without serious attenuation. The amplitude of the ultrasonic wave reflected from artificial flaw had a good linear relationship to the cross-sectional area of the flaw.

• 한국지구과학회:학술대회논문집
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• 2005.09a
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• pp.292-302
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• 2005

Science museum are the typical channels for students to experience science as outside school science lessons. Hereupon, in this study, middle school earth science contents system and achievement standards by the 7th Curriculum analyzed exhibit of science museum for basis. As a result, relevance between accomplishment level and Exhibition was insufficient in curriculum, and the area of geology in the exhibition overemphasized. Therefore, exhibit that consider curriculum is required. hereafter, Result of this study presents display of science museum and direction of education.