• The korean journal of orthodontics
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• v.47 no.6
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• pp.344-352
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• 2017

Objective: The purpose of this study was to compare the changes induced in the pharyngeal airway space by orthodontic treatment with bodily retraction of the mandibular incisors and mandibular setback surgery without extraction. Methods: This retrospective study included 63 adult patients (32 men and 31 women). Thirty-three patients who had been treated via four-bicuspid extraction and bodily retraction of the mandibular incisors (incisor retraction, IR group) were compared with 30 patients who had been treated via mandibular setback surgery (MS group) without extraction. Lateral cephalograms were acquired and analyzed before (T1) and after treatment (T2). Results: The superior pharyngeal airway space did not change significantly in either group during treatment. The middle pharyngeal airway space decreased by $1.15{\pm}1.17mm$ and $1.25{\pm}1.35mm$ after treatment in the IR and MS groups, respectively, and the decrease was comparable between the two groups. In the MS group, the inferior pharyngeal airway space (E-IPW) decreased by $0.88{\pm}1.67mm$ after treatment (p < 0.01). The E-IPW was larger in the MS group than in IR group at T1, but it did not differ significantly between the two groups at T2. No significant correlation was observed between changes in the pharyngeal airway space and the skeletal and dental variables in each group. Conclusions: The middle pharyngeal airway space decreased because of the posterior displacement of the mandibular incisors and/or the mandibular body. The E-IPW decreased only in the MS group because of the posterior displacement of only the mandibular body.

• Korean Journal of Mathematics
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• v.18 no.2
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• pp.175-183
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• 2010

The classical group completion theorem states that under a certain condition the homology of ${\Omega}BM$ is computed by inverting ${\pi}_0M$ in the homology of M. McDuff and Segal extended this theorem in terms of homology fibration. Recently, more general group completion theorem for simplicial spaces was developed. In this paper, we construct a symmetric monoidal 2-category ${\mathcal{A}}$. The 1-morphisms of ${\mathcal{A}}$ are generated by three atomic 2-dimensional CW-complexes and the set of 2-morphisms is given by the group of path components of the space of homotopy equivalences of 1-morphisms. The main part of the paper is to compute the homotopy type of the group completion of the classifying space of ${\mathcal{A}}$, which is shown to be homotopy equivalent to ${\mathbb{Z}}{\times}BAut^+_{\infty}$.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.100-100
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• 2004

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.62.3-63
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• 2017

The Mars Atmosphere and Volatile (MAVEN) mission has been providing valuable information on the atmospheric loss of Mars since its launch in November 2013. The Neutral Gass and Ion Mass Spectrometer (NGIMS) onboard MAVEN, was developed to analyze the composition of the Martian upper atmospheric neutrals and ions depending on various space weather conditions. We investigate a variation of upper atmospheric ion densities depending on the interplanetary coronal mass ejections (ICMEs). It is known that the Mars has a very weak global magnetic field, so upper atmosphere of Mars has been strongly affected by the solar activities. Meanwhile, a strong crustal magnetic field exists on local surfaces, so they also have a compensating effect on the upper atmospheric loss outside the Mars. The weak crustal field has an influence up to 200km altitude, but on a strong field region, especially east longitude of $180^{\circ}$ and latitude of $-50^{\circ}$, they have an influence over 1,400km altitude. In this paper, we investigated which is more dominant between the crustal field effect and the ICME effect to the atmospheric loss. At 400km altitude, the ion density over the strong crustal field region did not show a significant variation despite of ICME event. However, over the other areas, the variation associated with ICME event is far more overwhelming.

• Journal of Astronomy and Space Sciences
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• v.27 no.2
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• pp.123-128
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• 2010

This paper analyzes that the global positioning system (GPS) receiver differential code bias (DCB) has effect on the estimation the ionosphere total electron content (TEC). The data from nine permanent GPS sites of the Korea Astronomy and Space Science Institute (KASI) were used for the estimation of the receiver DCB before (Trimble 4000 SSi) and after (Trimble NetRS) the receiver replacement, using the singular value decomposition method. The results showed that the estimated mean value of the receiver DCB varied from 0.11 ns (nanosecond) to 7.54 ns before the receiver replacement, but the receiver DCBs shoed large values than 20 ns except some stations after the replacement. The receiver DCB showed a relatively large difference by types of the receivers, and, as a result, it had a great effect on the estimation the ionosphere TEC using GPS.

• Journal of Space Technology and Applications
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• v.2 no.2
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• pp.137-145
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• 2022

Space development has been independently performed by space agencies in each country. This causes redundant development for individual function, resulting in waste of space resources. Accordingly, Interagency Operations Advisory Group (IOAG) was established for standardization with mutual agreement between international organizations, and space resources can be used efficiently between space agencies through cross-support. IOAG define Service Catalog#1, #2, and #3, according to the network layer. In this technical paper, the background and main contents of the IOAG Service Catalog, and the application plan for domestic space development will be discussed.

• The korean journal of orthodontics
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• v.33 no.4 s.99
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• pp.223-233
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• 2003

The Purpose of this study was to Investigate the relationship between the space discrepancy of the mandibular dentition and craiofacial morphology in adults with good Angle class I occlusion. Dental casts of normal group, crowded group and spaced group were selected on the basis of dental crowding and spacing. Subjects with excessive space to accomodate the lower teeth were classified as spaced group(39). Subjects with a space discrepancy of more than 4mm were classified as crowded group(45). Normal subjects had little or no dental crowding and spacing(40). Various skeletodental measurements in lateral cephalograms were evaluated and compared by ANOVA, Pearson correlation analysis and multiple stepwise regression analysis. The results were as follows; 1. ANB angle was larger in crowded group than in spaced group. 2. Maxilla and mandible in crowded group were inclined more downward and forward than in spaced group, so crowded group was found to have vortical tendency. 3. Anterior cranial base length and mandibular body length were longer in spaced group than in crowded group. 4. According to the multiple stepwise regression analysis with space discrepancy as dependent variable, 40% of variance of space discrepancy could be explained by ANB angle, anterior facial height and ramus height. Multiple regression equation was as follows Space discrepancy=46.51-2.51ANB-0.58AFH+0.65RH

• Bulletin of the Korean Space Science Society
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• 2003.05b
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• pp.50-50
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• 2003

No Abstract, See Full Text

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.1
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• pp.21-28
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• 2011

The main purpose of this study is to analyze construction of space through the investigation of the cases of school community library through Gangneung-si's life-learning project and the findings from the analysis could be summarized as below. Firstly, most space used for school community library has the size of two classes in school on average and locals use generally space for reference and learning at school community library. Secondly, the construction of space of school community library is categorized into one for book-returning, references, reading, group learning and information, and an audio-visual space is also used for group learning and reading. A space for book-returning has features based on the location of its entrance and a space for reading features stand-up and sitting-on space considering size and usability. And a space for group learning has the feature of space planning that makes it possible for local people to get library programs and seminars and a space for information shows its feature of space planning that uses the wall.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.168-174
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• 2006

Background: Several biochemical mediators, such as substance P, calcitonin gene-related peptide (CGRP) and prostaglandin $E_2$, have been demonstrated to be involved in herniated or degenerated disc-induced radiculopathy. The authors tested the hypothesis that these mediators would existed in the epidural space of humans. Methods: Thirty nine patients were divided into two groups; 27 patients, who were diagnosed with spinal stenosis (stenosis group), and 12 scheduled for epidural anesthesia, without a history of back pain (control group). Under fluoroscopic guidance, an epidural catheter was introduced through the caudal space and placed into the anterior and posterior spaces, up to and around the epidural adhesive area, in the stenosis group. In the control group, the catheter was placed into the posterior epidural space through the L3⁣-4 or L4⁣-5 intervertebral space. Epidural irrigation was performed with 10 ml of saline, via an epidural catheter. Aspirated lavage fluid was collected, and the concentrations of biochemical mediators (substance P, CGRP and prostaglandin $E_2$) measured using an enzyme immunoassay kit. Results: Substance P, CGRP and prostaglandin $E_2$ were detected in all the epidural lavage fluids from both groups. The concentrations of substance P and prostaglandin $E_2$ in the stenosis group were higher than those of the control (P < 0.05). However, there was no difference in the CGRP levels between the two groups. In the stenosis group, the concentrations of these three mediators in the anterior epidural space were no different to those in the posterior space. Conclusions: These results suggest that biochemical mediators, such as substance P and prostaglandin $E_2$, in the epidural space might be partly involved in pain mechanism associated with spinal stenosis.