• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.4
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• pp.761-766
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• 2013

A precision linear motion table plays a crucial role in manufacturing systems used in various industries such as machine tools, semiconductors, and nanofabrication. In particular, one of the most typical mechanisms for a linear motion table is to use a ballscrew and LM guides. However, this mechanism is inevitably influenced by friction because of the relative motion in its joint regions. One of the most complex phenomena in friction is the hysteresis behavior of dynamic friction, which was compared with the steady dynamic friction that was presented using a Stribeck curve in this study. Therefore, we investigated the dynamic friction and its hysteresis behavior using a miniaturized linear table equipped with a ballscrew and LM guides that were lubricated with grease. Subsequently, it could be seen that hysteresis could be considered a time delay after zero-velocity crossing and that it was influenced by acceleration.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.78-89
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• 2007

Two design examples of deep foundations for high-rise buildings on soft ground are introduced in this paper. The first one is a 54-story building in Ho-Chi-Minh city, Vietnam, which was designed to be founded on $2.8m{\times}1.0m$ barrette foundations with approximately 60m to 75m depth. Based on a number of design guides and existing load test data from the construction sites in Ho-Chi-Minh city, the capacity of a barrette foundation in sand or clay layered ground was calculated to be 17.2MN to 27.8MN depending on the installing depth. The second one is a 40-story building in Baku city, Azerbaijan, which was designed to be supported by 2.0m diameter bored pile foundations with approximately 23m depth. As analytical or empirical guides for the local ground conditions were very limited, the design procedure from the SNiP Code, one of Russian specifications, was adopted and used to calculate the pile capacity. The capacity of bored pile foundation in highly weathered soil was expected to be 14.8MN to 15.5MN depending on the boring depth.

• Nutrition Research and Practice
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• v.7 no.3
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• pp.207-215
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• 2013

The objective of this study was to investigate the associations between the prevalence of overweight and obesity and the degree of adherence to the Korean Dietary Action Guides for Children (KDAGC). In a cross-sectional study based on a child care center-based survey in Seoul, Korea, we collected parental-reported questionnaires (n = 2,038) on children's weight and height, frequency of fruit and vegetable consumption, and the quality of dietary and activity behaviors based on the 2009 KDAGC Adherence Index (KDAGCAI) which was developed as a composite measure of adherence to the KDAGC. Overweight and obesity were determined according to age- and sex-specific BMI percentile from the 2007 Korean national growth chart. Associations were assessed with generalized linear models and polytomous logistic regression models. Approximately 17.6% of Korean preschool children were classified as overweight or obese. Obese preschoolers had lower adherence to the KDAGCAI compared to those with lean/normal weight. Preschoolers with a high quality of dietary and activity behaviors had a 51% decreased odds ratio (OR) of being obese (highest vs. lowest tertile of KDAGCAI-score, 95% CI 0.31, 0.78; P = 0.001); the associations were more pronounced among those who were older (P = 0.048) and lived in lower income households (P = 0.014). A greater frequency of vegetable consumption, but not fruit, was associated with a borderline significant reduction in the prevalence of obesity. Our findings support the association between obesity prevention and high compliance with the Korean national dietary and activity guideline among preschool children.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.353-368
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• 2020

This research investigates how pre-service music teachers demonstrated pedagogical content knowledge (PCK) and self-efficacy during a 16-week Music Education Course. 37 pre-service music teachers underwent peer mentoring, and prepared teaching guides and class teaching demonstrations. At the end of the course, the 37 participants' teacher self-efficacy and PCK components (namely pedagogical knowledge, representational knowledge, subject matter knowledge, assessment knowledge, student characteristics knowledge, curriculum knowledge, and context and social knowledge) were assessed. Data on their self-efficacy and PCK were gathered through a group interview and their self-reflection journals, and analyzed as phenomenological experience research. Analyses of the data show that pre-service music teachers acquired diverse knowledge. It also showed that peer mentoring enhanced the pre-service music teachers' self-efficacy, enabling them to prepare teaching guides and confidently demonstrate classes. Thus, diverse opportunities in research and practical class demonstrations contributed to pre-service music teachers' PCK and self-efficacy.

• English Language & Literature Teaching
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• no.6
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• pp.35-47
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• 2000

This study questions the validity of Crosslinguistic Influence (CLI) in EFL Learning. A ten-minute grammaticality judgement test involving resumptive pronouns in English relative clauses was given to 15 female subjects. The research results, which were analysed in terns of language transfer and universalist arguments, support the existence of a universal process that guides L2 learning, and some common developmental patterns between the two processes of L1 and L2 learning. Hence, the universalist view should be given at least equal Weight as the CLI approach.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.2
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• pp.303-308
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• 2002

Genetic markers engendered by genome projects drew enormous interest in quantitative genetics, but knowledge on genetic architecture of complex traits is limited. Complexities in genetics will not allow us to easily clarify relationship between genotypes and phenotypes for quantitative traits. Quantitative genetics guides an important way in facing such challenges. It is our exciting task to find genes that affect complex traits. In this paper, landmark research and future prospects are discussed on genetic parameter estimation and quantitative trait locus (QTL) mapping as major subjects of interest.

• ETRI Journal
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• v.41 no.5
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• pp.608-618
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• 2019

We propose a general framework for keyed learning, where a secret key is used as an additional input of an adversarial learning system. We also define models and formal challenges for an adversary who knows the learning algorithm and its input data but has no access to the key value. This adversarial learning framework is subsequently applied to a more specific context of anomaly detection, where the secret key finds additional practical uses and guides the entire learning and alarm-generating procedure.

• Nuclear Engineering and Technology
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• v.47 no.4
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• pp.479-487
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• 2015

The thallium-doped sodium iodide [NaI(Tl)] scintillation detector is preferred as a gamma spectrometer in many fields because of its general advantages. A silicon photomultiplier (SiPM) has recently been developed and its application area has been expanded as an alternative to photomultiplier tubes (PMTs). It has merits such as a low operating voltage, compact size, cheap production cost, and magnetic resonance compatibility. In this study, an array of SiPMs is used to develop an NaI(Tl) gamma spectrometer. To maintain detection efficiency, a commercial NaI(Tl) $2^{\prime}{\times}2^{\prime}$ scintillator is used, and a light guide is used for the transport and collection of generated photons from the scintillator to the SiPMs without loss. The test light guides were fabricated with polymethyl methacrylate and reflective materials. The gamma spectrometer systems were set up and included light guides. Through a series of measurements, the characteristics of the light guides and the proposed gamma spectrometer were evaluated. Simulation of the light collection was accomplished using the DETECT 97 code (A. Levin, E. Hoskinson, and C. Moison, University of Michigan, USA) to analyze the measurement results. The system, which included SiPMs and the light guide, achieved 14.11% full width at half maximum energy resolution at 662 keV.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.05a
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• pp.25-26
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• 2016

In this paper, the major changes of the national inspection in respect of the KAERI nuclear facilities were summarized. The frequency of the national inspection was decreased since the amendment of the Notification of the NSSC on the national inspection. But the national inspection broadened its scope and its implementation procedures and criteria were not clear. So, it is necessary to establish and enhance the national inspection system including the implementing guides and criteria. In addition, the internal regulation of the nuclear material accountancy for the nuclear facilities should be approved from the NSSC and observed by the KAERI in accordance with the national law. As the Notification of the NSSC on the national inspection was amended in Sep. 2014, it need to be revised to reflect the detail accountancy procedures and the preparation of the national inspection. So, KAERI will revise it to meet the international and national requirements as well as to implement the safeguards effectively at facility level.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.8
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• pp.1517-1523
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• 2016

The global medical tourism industry including Asian market has been activating recently. That is as medical tourists are motivated to seek the higher quality of healthcare with lower costs, as well as of travel. The consumers in this field tend to need customized services of medical tourism. It is needed that the consumers get customized information on medical services and traveling, the clinics and hospitals resolve the issues of offering translation and luring medical tourists from overseas, and the guides, who offer tour and translation service, provide the consumers and the clinics with customized services so that they get the services needed for one another. This research studies the Offline to Online, called O2O, matching platform based on global clinics, which connects medical facilities, patients, and guides for traveling and language services. It presents the customized marketing plans by utilizing customers' experiences from medical services and traveling they use.