• The korean journal of orthodontics
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• v.48 no.6
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• pp.349-356
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• 2018

Objective: This study was performed to investigate the alveolar bone of lower incisors in skeletal Class III adults of different vertical facial patterns and to compare it with that of Class I adults using cone-beam computed tomography (CBCT) images. Methods: CBCT images of 90 skeletal Class III and 29 Class I patients were evaluated. Class III subjects were divided by mandibular plane angle: high (SN-MP > $38.0^{\circ}$), normal ($30.0^{\circ}$ < SN-MP < $37.0^{\circ}$), and low (SN-MP < $28.0^{\circ}$) groups. Buccolingual alveolar bone thickness was measured using CBCT images of mandibular incisors at alveolar crest and 3, 6, and 9 mm apical levels. Linear mixed model, Bonferroni post-hoc test, and Pearson correlation analysis were used for statistical significance. Results: Buccolingual alveolar bone in Class III high, normal and low angle subjects was not significantly different at alveolar crest and 3 mm apical level while lingual bone was thicker at 6 and 9 mm apical levels than on buccal side. Class III high angle group had thinner alveolar bone at all levels except at buccal alveolar crest and 9 mm apical level on lingual side compared to the Class I group. Class III high angle group showed thinner alveolar bone than the Class III normal or low angle groups in most regions. Mandibular plane angle showed negative correlations with mandibular anterior alveolar bone thickness. Conclusions: Skeletal Class III subjects with high mandibular plane angles showed thinner mandibular alveolar bone in most areas compared to normal or low angle subjects. Mandibular plane angle was negatively correlated with buccolingual alveolar bone thickness.

• The korean journal of orthodontics
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• v.43 no.3
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• pp.134-140
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• 2013

Objective: To evaluate lower incisor position and bony support between patients with Class II average- and high-angle malocclusions and compare with the patients presenting Class I malocclusions. Methods: CBCT records of 79 patients were divided into 2 groups according to sagittal jaw relationships: Class I and II. Each group was further divided into average- and high-angle subgroups. Six angular and 6 linear measurements were performed. Independent samples t-test, Kruskal-Wallis, and Dunn post-hoc tests were performed for statistical comparisons. Results: Labial alveolar bone thickness was significantly higher in Class I group compared to Class II group (p = 0.003). Lingual alveolar bone angle (p = 0.004), lower incisor protrusion (p = 0.007) and proclination (p = 0.046) were greatest in Class II average-angle patients. Spongious bone was thinner (p = 0.016) and root apex was closer to the labial cortex in high-angle subgroups when compared to the Class II average-angle subgroup (p = 0.004). Conclusions: Mandibular anterior bony support and lower incisor position were different between average- and high-angle Class II patients. Clinicians should be aware that the range of lower incisor movement in high-angle Class II patients is limited compared to average- angle Class II patients.

• The Journal of Korean Association of Computer Education
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• v.20 no.4
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• pp.15-25
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• 2017

The purpose of this study is to verify the effectiveness of the flipped class by comparing Python programming classes divided into flipped class and general class. The participants who participated in each class had 36 students, so that they could participate in the class without knowing the difference of the class method. The students's academic achievement was applied the two groups with similar test items, and then the overall achievement were compared. The analysis showed that the achievements in flipped class in the basic grammar and intermediate grammar were higher than those in the general class. As a result of gender achievement analysis, there was no effect on the type of instruction. However, male student were generally higher in academic achievement. In conclusion, flipped class in the programming is a good way to improve students' understanding.

• Journal of Korean society of Dental Hygiene
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• v.21 no.6
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• pp.813-820
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• 2021

Objectives: This study was conducted to verify the effectiveness of the VR-applied head and neck anatomy class and to be used as basic data for the development of a teaching method using VR in the basic dental hygiene field. Methods: A convenience sample was extracted from 128 students and graduates who completed the head and neck anatomy class at the department of dental hygiene at a university in Gwangju. From June 1 to July 31, 2021, an online survey was conducted on class attitude and satisfaction, and statistical analysis was performed using frequency analysis and independent sample t-test. Results: Class attitude (3.79), interest (3.64), attention (3.88), learning motivation (3.80), and achievement motivation (3.84) were all high in the head and neck anatomy VR application group (p<0.01). Satisfaction (3.99), relevance of class content (4.06) and class achievement (3.96) were high in the head and neck anatomy VR application group (p<0.01). The suitability of class attitude (3.65) and class content (sub-item of class satisfaction) (4.13) was high in the group with the 4th industrial revolution education experience (p<0.05). Conclusions: The effect of VR application in the head and neck anatomy class was confirmed to increase students' class attitude and satisfaction. In the basic dental hygiene curriculum, it will be necessary to develop and utilize teaching methods related to the 4th industrial revolution and VR application classes.

• Journal of the Korean Institute of Educational Facilities
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• v.2 no.3
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• pp.31-38
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• 1995

The paper is to evaluate existing school building system with respect to students' comforts in the class room in Korea. This paper compared three styles of different school building system builted during last 20 years. Using statistical analysis, at first, the paper found that box-style structure is efficient for sustaining heat in the class room because it is compactly constructed. Secondly, air conditioning in the class room is important factor affected students' comforts in the summer time and for the smog occurring in the heating class room. Thirdly, we should compactly construct school building because the compactiveness of building components is important factor for student comforts. Fouthly, heating system in the class room should be changed. The system using gas or electricity insteded of coals should be introduced in the class room for the smog of the stove in winter time and for freshness in summer time.

• Journal of Korean Neurosurgical Society
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• v.44 no.1
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• pp.19-25
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• 2008

Objective : To analyze the relationship of concomitant foraminallumbar disc herniation (FLDH) with postoperative leg pain after microdecompression for extraforaminallumbar disc herniation (EFLDH) at the L5-S1 level. Methods : Sixty-five patients who underwent microdecompression for symptomatic EFLDH at the L5-S1 level were enrolled, According to the severity of accompanying FLDH, EFLDH was classified into four categories (Class I : no FLDH; Class II : mild to moderate FLDH confined within a lateral foraminal zone; Class III : severe FLDH extending to a medial foraminal zone; Class IV : Class III with intracanalicular disc herniation). The incidence of postoperative leg pain, dysesthesia, analgesic medication, epidural block, and requirement for revision surgery due to leg pain were evaluated and compared at three months after initial surgery. Results : The incidences of postoperative leg pain and dysesthesia were 36.9% and 26.1%, respectively. Pain medication and epidural block was performed on 40% and 41.5%, respectively, Revision surgery was recommended in six patients (9.2%) due to persistent leg pain, The incidences of leg pain, dysesthesia, and requirement for epidural block were higher in Class III/IV, compared with Class I/II. The incidence of requirement for analgesic medication was significantly higher in Class III/IV, compared with Class I/II (p=0,02, odds ratio=9,82). All patients who required revision surgery due to persistent leg pain were included in Class III/IV. Conclusion : Concomitant FLDH seems related to postoperative residual leg pain after microdecompression for EFLDH at the L5-S1 level.

• Journal of the Korean Institute of Educational Facilities
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• v.21 no.2
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• pp.3-12
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• 2014

Elementary School is a special facility where sense of place plays critical role for the development of children. Children in special education call for special attention as they hold inferior status compared to the children in regular class especially under the inclusive education policy. Eight cases of special education class area are analyzed in terms of social space, personal space and favorite place which is known to be basic factor for the development. As a result outdoor space found to be designed inappropriate even when designed accessible to the special education class as it could not meet the developmental needs of children in special education. Special education class area inside the building is also found to be too exclusive to allow social mix with children in regular class disregarding the intention of inclusive education. Location of these class should be strategic as it is critical to be linked with regular classroom efficiently still allowing psychological buffer as the children in special education tend to form restorative space inside the special education classroom showing the possibility of creating sense of place there.

• Journal of Electrical Engineering and information Science
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• v.1 no.1
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• pp.164-172
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• 1996

The partitioning of related objects should be performed before clustering for an efficient access in object-oriented databases. In this paper, a horizontal partition of related objects in object-oriented databases is presented. All subclass nodes in a class inheritance hierarchy of a schema graph are shrunk to a class node in the graph that is called condensed schema graph because the aggregation hierarchy has more influence on the partition than the class inheritance hierarchy. A set function and an accessibility function are defined to find a maximal subset of related objects among the set of objects in a class. A set function maps a subset of the domain class objects to a subset of the range class objects. An accessibility function maps a subset of the objects of a class into a subset of the objects of the same class through a composition of set functions. The algorithm derived in this paper is to find the related objects of a condensed schema graph using accessibility functions and set functions. The existence of a maximal subset of the related objects in a class is proved to show the validity of the partition algorithm using the accessibility function.

• Journal of the Korean Society of Earth Science Education
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• v.8 no.3
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• pp.367-377
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• 2015

The purpose of this study was to see the influences of POE science class that emphasizes explanation on science research ability, motivation of science class as well as scientific attitude of elementary students. The results drawn from this analysis were as below. Firstly, positive relationship was found between science research ability and POE science class was shown among research group. This shows that science research ability was improved as POE science class encouraged the research activities of students. It indicates that POE science class emphasizing explanation is effective in improving science research ability of students. Secondly, positive relationship was found between motivation of science class and POE science class among research group and this means that POE science class that emphasizes explanation stimulates intellectual curiosity of students and improves their attitude by actively promoting research activities. Thirdly, there was a positive relationship between scientific attitude and POE science class among research group. This presents that POE science class emphasizing explanation is effective in improving students' attitude toward science by promoting research activities. Above results show that POE science class emphasizing explanation is highly effective for elementary students. It is considered that scientific writing, discussion and debate classes have positive influences on research ability, motivation of science class and scientific attitude of elementary students. Thus, it is needed to apply POE science class to current science class as it can promote wider scientific activities among students.

• The Journal of the Korea Contents Association
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• v.17 no.5
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• pp.376-387
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• 2017

The creative class is the class of workers whose job is to create meaningful new forms. Recently, much attention has been focused on the role of the creative class in regional development. Many policy makers have invested to amenities to attract more creative class into their cities or regions for regional economic growth. However, there are only a few studies about the migration of the creative class in Korea. The purpose of this study is to make an analysis of the movement of the creative class by using the 17th Korean Labor & Income Panel Study. According to empirical results, the creative class are more likely to move than the non-creative class. The characteristic of creative class who moved is related to married man aged 20s and 30s without own house. Also, there is the difference between determinants of migration of the creative class and the non-creative class. It was founded that the most important determinants of migration of the creative class are housing related reasons such as home ownership and job reasons. Relationship, convenient facilities are not important factors when the creative class make a decision to move.