• Journal of the Korean Society for Heat Treatment
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• v.3 no.2
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• pp.32-36
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• 1990

For the accurate measurements of hardness in a material, it is necessary to have a thorough understanding of the effects of test variables on the accuracy of hardness value. For the rebound hardness test, major test variables are the radius of hammer ball tip, type of backing materials, size and roughness of the specimen. In this study, effects of these variables on Equo-Tip hardness value were investigated. Hardness measurements were carried out using WC balls with various sizes of worn-ot zone. The sample materials chosen for the experiments were commercial standard hardness blocks and SM45C steel bars subjected to either normalization or quench and temper treatments. As backing materials, aluminum, steel and rubber plates were used in all the experiments. Experimental results show that for the accurate measurements of Equo-tip hardness, it is necessary to use the hammer ball with a worn-out zone parameter of less than 0.23, and the recommended minimum thickness and width of the specimen are 25mm and 70mm, respectively. Further for the surface preparation, the specimens need to be polished with an emery paper of No. 400 or finer, and for the backing matrials, it is recommended to use steels or rubbers.

• Journal of the Ergonomics Society of Korea
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• v.34 no.3
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• pp.265-278
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• 2015

Objective:To study the sources of indoor noise, its effects on human health, noise assessment and regulation through the use of standards, and techniques used to reduce noise. Background: Noise significantly affects the living environment, and there are an increasing number of reports of its impacts on human health. Method: We reviewed domestic and foreign data regarding environmental noise, and examined its effects and the standards used to regulate noise levels. Results: We describe the major sources of indoor noise and suggest possible legal standards, as well as recommended criteria for the control of noise. Conclusion: South Korea has higher legal standards of environmental noise than international standards in terms of threshold values. People in Korea are exposed to various sources of noise, and therefore the reduction of noise is urgently required. Application: Depending on the features of indoor spaces, an appropriate degree of indoor noise can be determined and techniques to reduce excess noise are required.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2636-2640
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• 2003

KARI had developed an Local Area Augmentation System for aircraft precision landing as following ICAO SARPs(Standards and Recommended Practices) draft and FAA's recommended algorithm( carrier smoothing techniques). JPO in charge of managing GPS has introduced the signal structure of GPS modernization program. This paper estimates the accuracy performance of KARI-LAAS with modernized GPS signal but the same processing algorithm.

• Journal of the Korea Safety Management & Science
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• v.23 no.3
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• pp.1-9
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• 2021

Crane is an important equipment for the transport of heavy goods in industrial sites, but it is also known as one of the most fatal machines. In order to reduce crane accidents, it is necessary to minimize human errors during crane operations. To achieve this, ergonomic design principles are recommended to be reflected from the crane design stage. The study analyzed the safety certification standards for crane that should be fulfilled at the crane design and manufacturing stage. This study selected five representative ergonomic design principles (feedback, compatibility, consistency, full-proof, and fail-safe) by surveying heuristic evaluation principles that are widely used for usability evaluation in early design stage. Next, the principles were applied to the safety certification standards to identify insufficient clauses. This study identified 12 insufficient clauses out of 119 in the current safety certification standards for crane and discussed their improvement directions to comply the ergonomic principles. The analysis results of this study can help of improving the safety certification standards and the method used in this study can also be applied to identify insufficient clauses in the safety certification standards for other industrial machines such as press machine and lift.

• Journal of the Korean Society of Systems Engineering
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• v.13 no.1
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• pp.41-50
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• 2017

Systems engineering is being applied to various fields of industry such as national defense, aerospace, transportation, railway, and information technology industries. But in Korea, systems engineering has been selectively applied to government-driven projects such as space rocket development projects and unmanned flight development projects. And systems engineering processes introduced from international systems engineering standards has been directly applied to those projects. Unfortunately, this application method is not recommended as it requires highly experienced systems engineers. From our previous paper, we have proposed that domain specific engineering standards should be developed to be used as references for development of organizational engineering guide, so that more successful engineering performances can be achieved. And in this paper we have proposed a refinement of systems engineering processes from international systems engineering standards as they are bases of domain specific engineering standards.

• The Journal of Society for e-Business Studies
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• v.7 no.2
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• pp.69-81
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• 2002

The problem of the previous proprietary e-business systems is that they are not built upon well defined standards, which causes difficulties in extension of the system and interoperation among them. Therefore, a new e-business standard, ebXML, and related XML standards such as SOAP and XML Signature have been recommended for e-business systems. In this paper, as an application of the new XML standards, we design and implement a new internet bidding system. We use XML Schema for defining the document structure of the bidding system. DOM is used for structure search and XSL is used to represent styles. We use SOAP to handle distributed objects and XML Signature to provide data integrity. Due to the adoption of e-business standards, the developed system has advantages in interoperability and extensibility compared to previous systems.

• International journal of advanced smart convergence
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• v.9 no.2
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• pp.147-156
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• 2020

ACM's CSTA has drafted standards for computing curricula and recommended them to schools in the United States. The five core concepts of the US elementary school computing curriculum are computing systems, network and the Internet, data and analysis, algorithms and programming, and impacts of computing. In 2005, Korea prepared ICT education guidelines, including five fields, their subfields, and achievement criteria for each subfield. In the 2015 revised curriculum, software education was introduced and five achievement standards were set. The ACM CSTA has 18 achievement criteria up to K-2 and 21 achievement criteria up to K-5. If we compare the 39 achievement standards of the US to Korea, Korea's 2005 ICT education guidelines include 25 of these, and the 2015 revised curriculum includes 5 of them. In this study, we aim to study the CSTA achievement criteria that second graders should know and the achievement criteria that fifth graders should know. This is compared and analyzed with Korea's 2005 ICT Guidelines and 2015 Software Curriculum. In comparison with the number of achievement standards, the US elementary school's computing achievement standards are much higher than in Korea. Comparing with each standard, there are many areas that are not covered in Korean curriculum, and we can see that the 2015 curriculum has rather receded from 2005.

• Nutrition Research and Practice
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• v.5 no.3
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• pp.236-245
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• 2011

This study investigated the correlation between consumption of sugar intake by fifth grade students in primary schools and development of Attention Deficit Hyperactivity Disorder (ADHD). A total of 107 students participated, and eight boys and one girl (8.4% of the total) categorized as high risk for ADHD according to diagnostic criteria. There were significant differences in the occupations and drinking habits of the respondents' fathers between the normal group and risk group. In a comparison of students' nutrition intake status with daily nutrition intake standards for Koreans, students consumed twice as much protein as the recommended level, whereas their calcium intake was only 60% of the recommended DRI (dietary reference intake). Regarding intake volume of vitamin C, the normal group posted 143.9% of the recommended DRI, whereas the risk group showed only 65.5% of the recommended DRI. In terms of simple sugar intake from snacks, students in the normal group consumed 58.4 g while the risk group consumed 50.2 g. These levels constituted 12.5% of their total daily volume of sugar intake from snacks, which is higher than the 10% standard recommended by the WHO. In conclusion, children who consumed less sugar from fruit snacks or whose vitamin C intake was less than RI was at increased risks for ADHD (P < 0.05). However, no significant association was observed between total volume of simple sugar intake from snacks and ADHD development.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.04a
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• pp.138-141
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• 1986

After various oscillators have been reviewed, cesium beam frequency standards are recommended as the KRF(Korea Reference Frequency) source. We have investigated the characteristics of the SP-12M coaxial cable to find out whether it is usable for the network synchronization.

• Nutrition Research and Practice
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• v.17 no.1
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• pp.135-148
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• 2023

BACKGROUND/OBJECTIVES: In times of disaster, simplified and minimized nutritional standards are necessary for a quick response to provide nutritious relief food. This study aimed to develop nutrient-based nutritional standards for foodservice at shelters during disasters in the Republic of Korea (South Korea). SUBJECTS/METHODS: The standards were developed in 2 phases. First, nutrients to be included in the standards were selected. Initial candidates were selected considering 3 aspects: preceding standards, insufficient intake during disasters, and inadequate intake among South Koreans. Final selection was made by excluding nutrients for 3 reasons: nutrients for which there is no deficiency concern in South Korea, nutrients whose intake data were not available, or nutrients whose values presented by Dietary Reference Intakes for Koreans are difficult to achieve based on the current diet among South Koreans. Second, the reference values of energy and the selected nutrients were calculated. The reference values for the entire population who were 1-year-old and over were calculated by multiplying the estimated energy requirements or the recommended nutrient intake and the proportion of each age and sex group. Respective reference values were also calculated for 4 different age groups (1-5, 6-11, 12-64, and ≥ 65-year-old). RESULTS: The standards for the entire population were 2,000 kcal for energy, 55 g for protein, 650 ㎍ retinol activity equivalents for vitamin A, 95 mg for vitamin C, 1.1 mg for thiamin, 1.3 mg for riboflavin, 14 mg niacin equivalents for niacin, 350 ㎍ dietary folate equivalents for folic acid, 750 mg for calcium, and 11 mg for iron. Four additional standards corresponding to each age group were developed. CONCLUSIONS: The nutritional standards during disasters were developed for South Korea, including energy and 9 nutrients with reference values for the entire population and 4 different age groups. The standards will contribute to maintaining the health of disaster evacuees in South Korea.