• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.655-664
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• 1995

Sixty male patients with polysomnographically documented OSA were included in this study. A pair of cephalograms were obtained in the upright and supine positions. In the supine position, the ANB angle, lower facial height and the cross-sectional area of soft palate increased and there was a decrease in the vertical airway length and oropharynx cross-sectional area. Positional changes did not affect the cross-sectional area of tongue, but the cross-sectional area of the oropharynx decreased in the supine position. The obese group had higher AI and RDI. Maxillary unit length, C3-H, the cross-sectional areas of tongue, soft palate and oropharynx were significantly greater in the group Obese than in non-obese group. No correlation was noted between the mandibular unit length and OSA severity, The group of small mandibular unit length showed shorter lower facial height and maxillary unit length, and smaller cross-sectional area of tongue than the long mandibular unit length group. Hyold bone positioned more inferiorly and cross-sectional area of nasopharynx decreased as the OSA severity increased.

• Journal of Educational Research in Mathematics
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• v.19 no.2
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• pp.321-340
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• 2009

The purpose of this study was to analyze how lower graders in elementary school might respond to 4 different problem types in the context of measuring length: unit-length comparison, units and unit counting, unit-length expectation, and length comparison. A total of 375 students(185 second graders and 190 third graders) were surveyed and analyzed. The results showed that students were good at 'unit-length comparison' and 'units and unit counting', whereas they were not as to 'length comparison', This paper includes detailed analysis of students' responses as to both correct answer and incorrect one in conjunction with their typical answers and reasoning behind the answers. This paper suggests that teachers be sensitive to the certain level of reasoning tied to each type of problems and attend to students' difficulties in comparing length.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.634-639
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• 1998

A methodology based on the concept of variable string length GA(VGA) is developed for determining automatically the number of hyperplanes and their appropriate arrangement for modeling the class boundaries of a given training data set in RN. The genetic operators and fitness functionare newly defined to take care of the variability in chromosome length. Experimental results on different artificial and real life data sets are provided.

• Journal of Korea Water Resources Association
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• v.32 no.3
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• pp.291-300
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• 1999

The Snyder's synthetic unit hydrograph method is selected to apply the concept of the fractal dimension by stream order for the practicable rainfall-runoff generation, and fourth types of the Snyder's relation are derived from topographic and observed unit hydrograph data of twenty-nine basins. As a result of the analysis of twenty-nine basins and the verification of two basins, the Snyder's relation which considers the fractal dimension of the stream length and uses calculated unit hydrograph data shows the best result. The concept of the fractal dimension by stream order is applied to the Snyder's synthetic unit hydrograph method. The topographic factors, used in the Snyder's synthetic unit hydrograph method, which have a property of the stream length like $L_{ma}$ (mainstream length) and $L_{ca}$ (length along the mainstream to a point nearest the watershed centroid) were considered. In order to simplify the fractal property of stream length, it is supposed that $L_{ma}$ has not the fractal dimension and the stream length between $L_{ma}$ and ($L_{ma}\;-\;L_{ca}$) has the fractal dimension of 1.027. From the utilization of this supposition, a new Snyder's relation which consider the fractal dimension of the stream length occurred by the map scale used was finally suggested.

• Journal of Internet of Things and Convergence
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• v.3 no.2
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• pp.21-32
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• 2017

This study is a descriptive investigation for understanding factors influencing the length of stay in the postanesthesia care unit of elderly patients. Retrospective investigation was conducted on 300 patients aged 65 or older among those who had received an operation under general anesthesia and treated in postanesthesia care unit of hospital C located in Gyeonggi-do, from January 1 to December 31, 2014. The patients' average postanesthesia care unit stay was found to be 48.4 minutes and the 30-59 minute section accounted for the highest part with 58.0%. The postanesthesia care unit stay time according to intra-operative factors showed significant differences depending upon muscle relaxants, transfusion, ABGA, body temperature and total hours under anesthesia. Concerning the post anesthesia care unit stay length according to post-operative factors, significant differences were observed depending upon complications, PCA device, and circulatory drug use. In order to find out factors influencing the post anesthesia care unit stay length, the multiple regression analysis was conducted. As a result, the circulatory drug use and intra-operative lower body temperature were found to have an effect on the post anesthesia care unit stay length with the total explanatory power of 13%. Based on these findings above, it is deemed helpful to carefully monitor factors related to the post anesthesia care unit stay length and provide swift response accordingly for shorter post anesthesia care unit stay time of elderly general anesthesia patients.

• Journal of Korean Elementary Science Education
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• v.21 no.2
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• pp.201-212
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• 2002

This paper aims to find out how did elementary students understand scientific units in science textbooks. The subjects were 191 students of the 6th grade from 7 elementary schools in 3 different areas, consisting of 70 from 4 village schools of, 64 from 2 town schools of Gyeongnam province, and 57 from one city school in Ulsan Metro City. A test was developed based on the analysis of scientific units in the science textbooks and teacher's manuals constructed according to the 6th and 7th National Science Curriculum. The understanding of elementary students' on the scientific units(Temperature, Length, Weight, Volume, Speed, Plane Angle) were surveyed. The result are as follows: Regarding the temperature unit, the students generally well understand why to measure and how to read temperature, but had some problem in recording it, in confusion with the plane angle sign. As for the length unit, they obtained high scores in understanding the purpose of measuring length as well as recording and reading it. Which indicates that they are well aware of and use the unit appropriately. With respect to the weight unit, they got high scores in reading and recording weight, which means most students have no problem using the unit. However, it was found that they do not understand why to use the plate balance scale. The volume unit was one in which the students got relatively lower scores. They do not perceive the object of using a scale cylinder and confuse it with a device of length measurement. The unit of speed is the most difficult one for children's of science to understand, presumably, because it is an derived unit from two basic units. It is also assumed that the students got the highest score in the plane angle unit because they studied the unit immediately before the test. From the children's understanding of science units above the teacher's understanding and teaching methods presumed to play a major role for children to understand and use the science units properly.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.22-24
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• 2005

A study to assess and show applications of the easy lighting constructions of the new technics has presented in this paper, we have taken the present men-power to determine the optimum levels of the selected labour cost and analysis of the unit prices on the new developed lighting device for modularized to unit length, named Lite-way.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.567-570
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• 1988

This paper describes the design of FIR filtering DSP-chip that can be operated without programming. The proposed DSP-chip has not only the improvement of execution time but also selectivity of filter length from N=1 to N=128. Hilbert Transformer can be designed from this chip. FIR filter system is composed of Data memory/Control Unit, external memory and multiplier-accumulator. Data memory/Control Unit is laid out in this paper.

• Journal of Educational Research in Mathematics
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• v.18 no.2
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• pp.157-177
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• 2008

This paper provides a description of the process in development of textbook unit on measuring length for second grade in elementary school according to action research methodology. The teaching unit development has been done based on the new national mathematics curriculum released in 2006. Mathematical communication and positive attitude toward mathematics are highly emphasized in the new curriculum. These new foci have been analysed through literature review and interviews with two incumbent teachers to be respected in the unit in an appropriate way. Three stages of development with different ways of organizing contents and different problem contexts were reported in the paper.

• Journal of Korean Society on Water Environment
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• v.30 no.3
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• pp.319-328
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• 2014

Dorang - the Korean term for headwater streams - occupy a large portion of the total stream length in a basin, and contribute significantly towards the quantitative and qualitative characteristics, and the ecosystem, of the main river. The Ministry of Environment of South Korea has supported the investigation of the status of Dorang in the nation's four major basins, since 2007. Without a widely accepted academic or legal definition of Dorang, however, there are limits to understand the distribution of Dorang at the national scale and to systematically compile a Dorang database. This paper, through a review of the stream classification system and Korean legal system delineating streams, defines Dorang as 1st and 2nd order streams according to the Strahler ordering method, in a 1:25,000 geographical scale. Analysis of the Geum River basin, with this definition, reveals that the total length of Dorang is 20,622.4 km (73.6% of total stream length), and the number of Dorang catchments is 23,639 (71.3% of the basin area). Further analysis of the geomorphological characteristics of Dorang catchments shows that the average total stream length is 1.1 km, average catchment length is 1.2 km, average drainage area is $0.4km^2$, and average drainage density is 3.08/km.