• Sleep Medicine and Psychophysiology
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• v.15 no.2
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• pp.67-70
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• 2008

Overlap syndrome can be defined as a coexistence of chronic obstructive pulmonary disease (COPD) and sleep apnea-hypopnea syndrome (SAHS). The association of COPD and SAHS has been suspected because of the frequency of both diseases. Prevalence of COPD and SAHS is respectively 10 and 5% of the adult population over 40 years of age. However, a recent study has shown that the prevalence of SAHS is not higher in COPD than in the general population. The coexistence of the two diseases is only due to chance. SAHS does not affect the pathophysiology of COPD and vice versa. Prevalence of overlap syndrome is expected to occur in about 0.5% of the adult population over 40 years of age. Patients with overlap syndrome have a more profound hypoxemia, hypercapnia, and pulmonary hypertension when compared with patients with SAHS alone or usual COPD patients without SAHS. To treat the overlap syndrome, nocturnal noninvasive ventilation (NIV) or nasal continuous positive airway pressure (nCPAP) can be applied with or without nocturnal oxygen supplement.

• Journal of Korean Elementary Science Education
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• v.34 no.1
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• pp.72-85
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• 2015

Conception in learner's cognitive structure has a niche as species in ecosystems. The purpose of this study is to analyze the change of niche overlap of photosynthesis concept through instruction. The photosynthesis concepts were selected from literature review. Selected concepts were in 4 areas: Location of photosynthesis, reactants, products, and environmental factors. The subjects consisted 304 elementary students. The respondent marked the relevance between the presented concepts and each area on a scale of 1~30 points. The analysis of niche overlap in concepts was performed by changing in niche overlap graph, niche space size, and overlap index before and after instruction. The results are as follows. First, on the whole understanding level and relevance of the scientific concepts was increased through instruction as a result of learning. Second, elementary school students cognitive concepts in the form of chunking concepts through classification process. Based on the results, this study has the following suggestion. Students' conceptual ecologies and niche analyzed by this study will be used as material for development of instruction strategy.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.11
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• pp.17-23
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• 2010

Titanium alloy is one of the hard processing materials made by the traditional manufacturing method because of the excellent mechanical strength. Ablation of titanium alloy is investigated by using a femtosecond laser which is a regenerative amplified Ti:sapphire laser with 1kHz repetition rate, 184fs pulse duration time and 785nm wavelength. Experiments are carried out under various ablation conditions with different pulse overlap ratios for the rectangular shape and micro hole. Test results show that the ablation characteristic according to pulse overlap ratio of titanium alloy seems to be as non-linear type at the different zone of energy fluence. The optimal condition of rectangular shape processing is obtained at the laser peak power 1.3mW, pulse overlap ratio of 90%, beam gap of $1\;{\mu}m$. The micro hole has a good quality from the pulse overlap ratio of 99% at the same laser peak power. With the optimal processing condition, the fine rectangular shape and micro hole without burr and thermal damage are achieved.

• The Journal of Information Systems
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• v.29 no.1
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• pp.267-287
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• 2020

Purpose Online platform companies can increase the spread of content by communicating with users who have diverse preferences through social networks. Previous studies show the mixed effect on the network overlap, and there was a limited examinations for the underlying mechanism. This study expects high academic and practical implications that can be provided by studying on the user's viewership network. The purpose of this research is to examine the effects of network overlap on the users' viewership for creators of user-generated content in YouTube. We explain the direct and in-direct effects through the content sharing and the valence of user ratings. Design/methodology/approach The data contains 45 channels and 4,085 video clips from YouTube. We control the effect of the categories, channel characteristics, and vide clip characteristics on the viewership. PROCESS macro were used to analyze the direct and in-direct effects of network overlap. Findings The analysis results showed that the network overlap directly affect on the users' viewership. The variable decreases the moderators (i.e., content sharing and the valence of user ratings). This result implies that the users can not satisfy their need for uniqueness which is achieved by content sharing and rating in the overlapped network.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2C
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• pp.99-104
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• 2011

The chirp spread spectrum (CSS) technique spreads the data signal over a frequency bandwidth wider than minimum required bandwidth. By using time overlapping, the bit rate in CSS can be increased. However, for reliable transmission of data signal, the intersymbol interference (ISI) due to overlap should be analyzed. In this paper, the relation between the degree of overlap and ISI is analyzed in direct modulation binary phase shift keying CSS systems. In some cases, the overlap does not incur ISI at all and the ISI fluctuates or monotonically increases as the number of overlaps changes. It is also shown that the simulation results closely agree with the analytic results.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.2
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• pp.118-123
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• 2016

Overlap cutting is a fundamental method of applying abrasive water jet (AWJ) machining to milling to produce a wider surface because the nozzle outlet is approximately 1.0 mm wide. In this study, the effects of overlap cutting on the depth profile and surface roughness are investigated. The overlapping area depends on the amount of step over, which is controlled in the pick-feed direction. If the step over is equal to or larger than the diameter of the nozzle, no overlap cut occurs but large cusps remain between the cut paths. A step over as small as one-thirds of the nozzle diameter may lead to triple-overlap cutting resulting in an extraordinary depth. By using pocket milling experiments with a step over of 0.46 (or 0.47), it is verified that AWJ can produce a milled surface of titanium, one of the hard-to-cut materials, with $76{\mu}m$ Ra.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.504-507
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• 2009

Autoimmune hepatitis (AIH), primary sclerosing cholangitis (PSC), and primary biliary cirrhosis (PBC) are chronic autoimmune liver diseases. Overlap syndrome is defined as a condition in which the clinical, biochemical, and histological features of these autoimmune diseases are overlapped. Thus, it is difficult to appreciate overlap syndrome as an actual diagnostic entity. Only a few cases of the overlap syndrome of AIH and PSC have been reported, especially in children. Moreover, PSC is known to be the most frequent liver disorder associated with inflammatory bowel diseases such as ulcerative colitis. We report one case of AIH-PSC overlap syndrome in a child who was diagnosed as having ulcerative colitis.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.1-9
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• 2006

The single lap joint is the most studied joint in the literature in terms of both theory and practice. It is easy to manufacture and the lap shear strength is a useful value for strength assessment and quality control. Simple design rules exist such as the one present in standard ASTM 1002 or in a recent paper by Adams and Davies. The main factors that have an influence on the lap shear strength are the type of adhesive, i.e. ductile or brittle, the adherend yield strength and the overlap length. The overlap increases the shear strength almost linearly if the adhesive is sufficiently ductile and the adherend does not yield. For substrates that yield, a plateau is reached for a certain value of overlap corresponding to the yielding of the adherend. For intermediate or brittle adhesives, the analysis is more complex and needs further investigation. In order to quantify the influence of the adhesive, the adherend and the overlap on the lap shear strength, the experimental design technique of Taguchi was used. An experimental matrix of 27 tests was designed and each test was repeated three times. The influence of each variable could be assessed as well as the interactions between them using the statistical software Statview. The results show that the most important variable on the lap shear strength is the overlap length followed by the type of adherend.

• The Journal of Korean Medicine
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• v.22 no.2
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• pp.31-40
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• 2001

This experimental studies was to investigate location of labeled neurons in CNS following injection of pseudorabies virus(PRV), Bartha strain, into the uterus and Sanyinjiao(Sp6) of rats. After survival times of 4-5 days following the injection of PRV, the rats were perfused, and their brain and spinal cord were frozen sectioned($30\mu\textrm{m}$). These sections were stained by PRV immunohistochemical staining methods, and observed with light microscope. The results were as follows: 1. In the spinal cord, overlap areas of PRV labeled neurons projecting to uterus and Sp6 were observed in lamina VII, IX and X areas of cervical segments. In thoracic segments, overlap areas were observed in lamina IV, VII, X and intermediolateral n.. In lumbar segments, overlap area of PRV labeled neurons were observed in lamina I, V-VII, IX, X and intermediolateral n.. In sacral segments, overlap areas of PRY labeled neurons were observed in lamina N, V, VII, X and sacral parasympathetic n.. 2. In the brain, overlap areas of PR V labeled neurons projecting to the uterus and Sp6 were observed in lateral paragigantocellular n., rostroventrolateral reticular n., raphe obscurus n., raphe pallidus n., raphe magnus n., locus coeruleus n., Barrington's n., A5 cell group, central gray n., paraventricular hypothalamic n. and arcuate n. This results suggest that overlap areas of PRV labeled neurons of the spinal cord projecting to the uterus and Sp6 might be the first-order neurons related to the viscera-somatic sensory and sympathetic preganglionic neurons. PRV labeled neurons of the brain may be the second and third-order neurons response to the movement of smooth muscle of uterus. These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory and motor system monitoring the internal environment. These overlap areas of spinal cord and brainmay be related to autonomic centers related to regulation of uterus.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.376-385
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• 1991

For manufacturing trimming-free plates which have rectangular shaped edges and straight edges in as-rolled state, it is necessary to investigate rolling characteristics of overlap, bulge and width deviation etc. in a standardized plate rolling process. The present wok is for preventing edge overlap as the first approach to develop trimming-free plate rolling technique. An experimental study on overlap control was done with plasticine material in order to examine influence factors and find a control method by use of a laboratory mill scaled down to one tenth of actual production mill. It was found that edge overlapping was increased with the increase of slab thickness and of broadside rolling ratio, but decreased with the increase of chamfered amount on slab edges. In the simulated rolling experiment with edge chamfered slabs of various chamfered angles, the chamfered angle of 60.deg. was the most effective one for reducing overlapping irrespective of slab thickness and of broadside rolling ratio.