• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.2
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• pp.347-353
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• 2017

In order to prohibit global warming, various kinds of regulatory policies have been established in the whole world. One example is the establishment of the Renewable Portfolio Standard. It requires the increased portion in energy production from renewable energy sources. The Republic of Korea adopted the act on the promotion of the development, use, and diffusion of new and renewable energy since 2012. However, in spite of the effort on the consideration of the renewable energy sources, it was reported the carbon intensity of electricity in Korea was not that low in 2015. Thus, it is required to examine the recent state of the utilization degree of the renewable energy sources in Korea. This paper analyzed the statistical data provided by Korea Power Exchange (KPX) to examine any problems and solutions for generating electricity from the renewable energy sources. We focused on the generation capacity provided by the power plants participated in the market, the electric power trading amount, and the utilization coefficient for 10 years. By analyzing the data, we provide an alternative to solve some imbalance among the factors contributing to renewable energy use.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.1
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• pp.208-220
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• 2015

This study analyze Online class's current condition in Smart era. And suggest better operation model based on Internet Architecture. This study focuses the condition of e-learning operation model in University online class. Especially, 'Time Check Idea' that using for attendance on e-learning class has some side effects. So this study would applied 'Qualitative Check Idea Concept' on e-learning class. Question Based System, QBS is example model. QBS is leading a Learner's participation in e-class by Making Quiz. These quizs are shared with other students and refer to studing contents. Practically operating Qualitative Concept model QBS on university e-class, we can seek for the effectiveness of Qualitative e-learning model QBS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1637-1645
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• 2011

This study explores the plausible socio-economic variables that influence joint choice of tenure and dwelling type in Cheonan. For estimating these joint choice models, multinomial logit framework is employed. Following the practice of other studies, we chose the age of householder, education level of householder, occupation of householder, residence duration in Cheonan, experience of capital area residence, plan of capital area move and the monthly income of household as socio-economic variables, and size of house, access of subway area, residence area as house characteristics. According to the estimation result, we can derive som implications. For example, the higher monthly income of household, more member of student, bigger size of house, longer residence duration of Cheonan, the more they prefer owing house apartment to renting it. In addition, as householders are older, size of house is bigger, they prefer owing-non apartment to owing house-apartment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.5925-5932
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• 2014

The aim of this study was to develop assessment tools for analyzing society focusing on abilities, not an academic clique. The development of a type of occupational qualification, which is called a working and learning system, for Koreans, can be reliable and acceptable to a variety of society members. This study was conducted by searching for a dual system and examining a qualification system in developed countries. To achieve the goal of this study, the management status according to a type of qualification system was analyzed. In addition, a variety of related laws, related department, testing authority, testing institute, terms of applying for tests, way of testing, committee of testing, testing subjects, criterion for passing tests, a status of qualification test administrated in some developed countries, such as Germany, UK, the USA and Australia, were conducted. The occupational duty of the machine field and education contents are examined by analyzing the occupational duty. In addition, the criterion to solve problems and a way of marking in the field of machines were indicated and an example of written and practical tests is presented. This study makes a blueprint for a qualification system of working and learning at the same time in a national dimension.

• Animal Systematics, Evolution and Diversity
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• v.24 no.1
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• pp.25-32
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• 2008

The Gold-spotted pond frog, Rana plancyi chosenica, designated as a vulnerable species by IUCN Red list. This species is a typical example facing local population threats and extinction due to human activities in South Korea. A strategic conservation plan for this endangered species is urgently needed. In order to provide information for future conservation planning, accurate information on the genetic diversity and taxonomic status is needed for the establishment of conservation units for this species. In this study, we used a molecular genetic approach using the mitochondrial cytochrome b gene and control region sequences to find the genetic diversity of gold-spotted pond frogs within South Korea. We sequenced the mitochondrial DNA cytochrome b gene and control region of 77 individuals from 11 populations in South Korea, and one from Chongqing, China. A total of 15 cytochrome b gene haplotypes and 34 control region haplotypes were identified from Korean gold-spotted pond frogs. Mean sequence diversity among Korean gold-spotted pond frogs was 0.31% (0.0-0.8%) and 0.51% (0.0-1.0%), respectively. Most Korean populations had at least one unique haplotype for each locus. The Taean, Ansan and Cheongwon populations had no haplotypes shared with other populations. There was a sequence divergence between Korean and Chinese gold-spotted pond frogs (1.3% for cyt b; 2.9% for control region). Analysis of genetic distances and phylogenetic trees based on both cytochrome b and control region sequences indicate that the Korean gold-spotted pond frog are genetically differentiated from those in China.

• Korean Journal of Community Nutrition
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• v.9 no.2
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• pp.121-134
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• 2004

Purpose of this study was to compare nutrient intakes of disabled children and non-disabled children. Subjects consisted of 86 disabled children from a special education school and 127 non-disabled children from an elementary school in Seoul. Nutrient intakes were assessed by modified 24-hr recall method, with the help of children's parents and teachers. Almost all nutrient intakes (energy, protein, fat, carbohydrates, vitamin B$_1$ and niacin) of children with cerebral palsy were significantly lower than those of other groups. But nutrient intakes per body weight of children with cerebral palsy were not significantly different with those of other groups. There was no significant difference between disabled and non-disabled children in almost % RDA (rate of actual intake to RDA) except of energy %RDA in children with cerebral palsy. NARs (nutrient adequacy ratio) for energy and vitamin B$_1$ of children with cerebral palsy were significantly lower than those of children with autism and mental retardation, and non-disabled children. The proportions of energy, carbohydrate and protein intakes from lunch were significantly higher than those from breakfast and dinner in children with mental retardation and autism. The nutrient intakes of disabled children were different between other groups according to the type of handicap. For example, children with cerebral palsy had the risk of undernutrition. On the other hand, autistic children had the tendency of overnutrition. These results suggest that nutrition educational programs and educational materials for disabled children, their teachers and their parents should be developed considering the type of handicap.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2253-2260
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• 2009

The typical distribution systems have the power flow from distribution substations (sources) to customers (load) only as one direction. However, in the case where new energy power sources are connected to distribution systems, the output variations of new energy sources to distribution systems, which is so called reverse power flow, may cause the bi-directional power flow. So, the reverse power flow has severe impacts on typical power system, for example power quality problems, protection coordination problems, and so on. Therefore, this paper proposes the algorithm for Multi-functional protection devices in distribution systems in the case where new energy sources are interconnected. The proposed algorithm is verified to show the effectiveness by simulating and experimenting the prototype systems.

• Journal of KIISE:Software and Applications
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• v.30 no.11
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• pp.1044-1053
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• 2003

A virtual science experience space(VSES) using virtual reality technology including haptic device is proposed to overcome limits which the existing science education has and to improve the effect of it. Four example scientific worlds such as Micro World, Friction World, Electromechanical World and Macro World are demonstrated by the developed VSES. Van der Waals forces in Micro World and Stick-Slip friction in Friction World, the principle of induction motor and power generator in Electromechanical World and Coriolis acceleration that is brought about by relative motion on the rotating coordinate are modeled mathematically based on physical principles. Emulation methods for haptic interface are suggested. The proposed VSES consists of haptic device, HMD or Crystal Eyes and a digital computer with stereoscopic graphics and GUI. The proposed system is believed to increase the realism and immersion for user.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.34-50
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• 2012

This study set out to define a communication environment between an ITS center and field device required to be introduced in the nation in order to guarantee the interoperability, compatibility, and global competitiveness of communication between them in the nation. It also aimed to establish technical and policy plans for its introduction, develop an emulator for information exchange, and apply VMS by way of showing an example, thus testing its validity. First, a standard environment for information exchange between an ITS center and field device required to be introduced in the nation was defined as a dual protocol between DATEX and SNMP. The study also proposed a message definition system including meta-attribution definition and OID introduction. The study then suggested technical and policy plans for its introduction including securing enough feasibility with feedback through a model project of standard introduction, offering education and promotions for the standard in advance, providing methods to introduce and systematically manage OID, developing a hardware standard proper for the information exchange standard, and setting up an integrated management system to introduce a dual protocol.

• Journal of agriculture & life science
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• v.43 no.4
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• pp.21-31
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• 2009

Dipterans are excellent insects to serve as forensic indicators to determine the postmortem interval of a human corpse. Therefore, we undertook a study to identify the major dipterans that are attracted to and develop in vertebrate carcasses. To determine what dipterans occur in Korea, chicken carcasses were placed in various habitats including the forest, open field, stream bank, greenhouse, rooftop, rice paddy, Chinese cabbage field, vacant hut, and pond at different times of the year. The dipterans were collected at various time intervals after placement in each habitat until the end of decomposition and identified. Our results showed that 49 identified and unidentified dipteran species from 36 genera in 19 families were collected from the carcasses. Habitat placement influenced the number of species isolated from the carcasses. For example, 39 species were collected from the forest habitat, 28 species from the open field, stream bank, or greenhouse each, 16 species from a vacant home, and 12 species from the pond. The dipteran species that were collected from all habitats were Phaenicia sericata, Lucilia illustris, and Lucilia sp. in the family Calliphoridae and Boettcherisca peregrine in the family Sarcophagidae. Other dipteran species that were isolated depended on carcass placement that is, fewer dipteran species were observed from carcasses in the backpack and much more species were recorded from unburied carcasses than buried carcasses. P. sericata, L. illustris, Lucilia sp., B peregrine and an unidentified sarcophagid species were observed year round, but some dipterans showed seasonal differences.