• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.355-373
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• 1995

Craniofacial region is a musculodentoskeletal system that consists of many anatomical structures ; cranioskeletal structures, dental arches, and formation and functions of masticatory muscles have close correlations. Growth and development of craniofacial region are influenced by not only hereditory factors, but also environmental factors such as craniofacial muscles and surrounding tissues. On the contrary, however, study on changes in functions or adaptations of craniofacial muscles following changes of craniofacial skeletal structures has been somewhat insufficient. The author's purpose was to observe correlations between masticatory muscular functions and change patterns according to cranial skeletal structures and occlusion patterns, for this, comparative study of muscle activity changes of preand post- orthognathic surgery states in skeletal Cl III malocclusion patients was peformed. The selected sample groups were 15 normal male patients, 15 skeletal Cl III pre-orthognatic surgery patients and 15 skeletal Cl III post-orthognatic surgery patients. For each sample groups, cephalometric x-ray taking, masticatory efficiency test and measurements of muscle activities in anterior temporal muscle, masseter and upper lip in rest, clenching, chewing and swallowing were carried out. The following results were obtained : 1. In resting state of mandible, pre-surgery malocclusion group showed higher m. activities in ant. temporalis, masseter and upper lip than post-surgery group. Post-surg. malocc. group showed significantly high m. activity only in upper lip compared to the normal group. 2. In clenching state, post-surg. malocc. group showed higher m. activities in ut. temporalis, masseter and upper lip than pre-surg. malocc. group. 3. In chewing state, post-surg. malocc. group showed higher m. activities in ant. temporalis and masseter than pre-surg. malocc. group, on the other hand, decreased upper lip activity was noticed. 4. In swallowing state, post-surg. malocc. group showed lower upper lip activity than pre-surg. malocc. group but higher than that of the normal group. No significant difference in m. activities of ant, temporalis and masseter was noticed among the three groups. 5. Masticatory efficiency was lower in pre-surg. malocc. group than normal group, masticatory efficiency showed an increase in post-surg. malocc. group compared to the pre-surg. malocc. group. However, both groups showed significant differences compared to the normal group.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.101-110
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• 2010

Purpose: This study has been conducted in order to examine the oral health status and dental prostheses status, and the effects of dental prostheses to the oral health related quality of life among the elderly using social welfare centers. Material and methods: For this purpose, the researcher conducted a questionnaire survey and oral examination of 275 samples of old persons using 7 social welfare centers located in Daejeon metropolitan city. The oral health related quality of life was measured by GOHAI (Geriatric Oral Health Assessment Index). Results: 1. The less age and the more education and the more subjective economic status and living with spouse of family status, the higher GOHAI showed. 2. Mean age of first using of removable denture is 62.11 years old and average life cycle of removable denture is 10.76years. 57.5% of study subjects use removable denture and complete denture user of study subjects are 13.8%. 3. In the case that they use fixed prostheses rather than removable ones and in the complete denture they use both sides (upper and lower) rather than single side, showed higher GOHAI. 4. In the case that they showed higher degrees of satisfaction with dental prostheses and can use them always and showed no necessity for new dental prostheses and denture adaptation is good, GOHAI showed higher. Conclusion: In order to improve oral health related quality of life among the elderly who have many missing teeth, it is required to restore their masticatory ability to the normal level by restoring the missing teeth which has lost its function through providing proper dental prostheses.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.368-373
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• 2010

The incisors function as instruments for biting and cutting food during mastication. They also support the lips and face and maintain vertical dimension. In addition, they contribute to overall normal arch appearance. They play important role during the articulation of speech and assist in guiding jaw closure. Extraction and space maintenance are the most common treatment for a tooth with poor prognosis. However, in the mixed dentition, extraction of the upper permanent incisors results in many complications, such as resorption of alveolar bone, poor esthetics, pronunciation, and mastication. Considering these various roles of incisors in oral cavity, approach for traumatized incisors, even the ones with poor prognosis, should be considered first prior to simple extraction. The dentist must take into account the age of the patient, growth potential, occlusion, oral hygiene status, economic status and motivation towards dental health in addition to patient compliance. In this case, although the prognosis was predicted to be unfavorable due to short root and mobility, we could save the central incisor using conservative treatment, reposition by orthodontic appliance instead of extraction.

• Journal of Oral Medicine and Pain
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• v.32 no.3
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• pp.293-303
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• 2007

The purpose of this paper is to evaluate if there is a relationship between anterior disc displacement without reduction and development of anterior open bite, and a relation between occurrence of open bite and occlusal appliance therapy. In general, the statistically significant differences were found between the Group 1 and 2 and normal mean group. The variables that represent mandibular size and form, showed a statistical significance in all 3 groups. Also 3 groups patients had a smaller ANB, a larger FMA than normal mean group. When we compared the 3 groups with respect to all cephalometric measurements by One-way analysis of variance (ANOVA), group 1 and 2 patients had a larger FMA, a larger SN to mandibular plane angle, a larger maxillomandibular plane angle, a larger occlusal plane to mandibular plane angle, a smaller total posterior facial height/total anterior facial height(%), and a larger gonial angle than group 3. The statistically significant differences were not found between the Group 1 and 2, and skeletal patterns were similar. Thus, morphologic features of patients with vertical discrepancies may represent a risk factor for the development of anterior open bite with or without occlusal appliance treatment. In case of patients with vertical discrepancy, we may have to be more careful when inducing a change of the vertical dimension.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.3
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• pp.207-214
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• 1995

'Ihis experiment was canied out to investigate the feed intake, chewing activities and ruminal characteristics by change in roughage intake and concentrate feeding amount with 15 Holstein cows. 1. DM intake of cow fed rice straw, corn silage and grass hay was 4.97, 5.47 and 5.60% of metabolic weight, respectively, and that by kg increase of concentrate was decreased by 0.330, 0.294 and 0.461 kg, respectively. 2. RVI of rice straw, com silage and grass hay was 98.3, 93.7 and 87.1 respectively, and correlations between RVIfl) and concentrate level@) were the following; $Y_1$(rice straw) = 99.4543 - 5.9759X + 0.0230$X^2$ This experiment was carried out to investigate the feed intake, chewing activities and ruminal characteristics by change in roughage intake and concentrate feeding amount with 15 Holstein cows. 1. DM intake of cow fed rice straw, corn silage and grass hay was 4.97, 5.47 and 5.60% of metabolic weight, respectively, and that by kg increase of concentrate was decreased by 0.330, 0.294 and 0.461 kg, respectively. 2. RVI of rice straw, com silage and grass hay was 98.3, 93.7 and 87.1 respectively, and correlations between RVI(Y) and concentrate level(X) were the following; $Y_1$(rice straw) = 99.4543 - 5.9759X + 0.0230$X^2$ $Y_2$(com silage) = 88.7601 - 2.9000X - 0.2111$X^2$ $Y_3$(grass hay) = 95.1515 - 6.3096X + 0.0873$X^2$ 3. Average ruminal pH in rice straw feeding group was the highest and correlations between ruminal pH(Y) and concentrate level(X) were the following; $Y_1$ = 7.0920 - 0.0309X - 0.0023$X^2$ $Y_2$ = 6.5000 - 0.0516X + 0.0002$X^2$ $Y_3$= 6.7666 - 0.0072X - 0.0044$X^2$ 4. Average ruminal $NH_3-N$ concentration in forage hay feeding group was the highest and correlations between ruminal $NH_3-N$ concentration(Y) and concentrate level(X) were the following. $Y_1$ = 3.3777 - 0.0587X + 0.0682$X^2$ $Y_2$ = 4.2765 + 0.5921X + 0.0181$X^2$ $Y_3$= 5.3634 - 0.4203X + 0.0223$X^2$ 5. Ruminal VFA wncentmtion in corn silage feeding group was the highest.

• The korean journal of orthodontics
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• v.22 no.3 s.38
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• pp.735-753
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• 1992

The purpose of this study was to analyze the positions of upper and lower incisors according to facioskeletal patterns. The lateral cephalometric radiographs of sixty persons with normal occlusion, forty persons with Class II Division 1 malocclusion, and forty persons with Class III malocclusion all above the age of 18, were analyzed. The following results were obtained. 1. C I angle, the measurement related to masticatory system, were $89.20{\pm}4.34^{\circ}$ in normal occlusion group, $81.68{\pm}士5.95^{\circ}$ in Class II Division 1 malocclusion group and $101.96{\pm}6.31^{\circ}$ in Class III malocclusion group. 2. In comparison with the positions of upper and lower incisors according to facioskeletal patterns, Class II Division 1 malocclusion group showed that upper incisors were different significantly in all measurements and inclined labially (P < 0.05). Lower incisors were different significantly in all measurements except LI-APog, LI-APog (mm), LI-AB, LI-AB (mm) and inclined labially (P < 0.05), Class III malocclusion group showed that upper incisors were different significantly in all measurements except UI-SN, UI-OP, and inclined labially (P < 0.05). Lower incisors were different significantly in all measurements and inclined lingually (P < 0.05). 3. In all facioakeletal patterns, LI-SN and LI-PH ware correlated moderately to facioskeletal measurements, and FMA was correlated moderately to measurements of lower incisor position. 4. Regardless of the facioskeletal patterns, the reference planes equally applicable were AB line in the measurements of upper incisor and APog line in the measurements of lower incisor.

• The Journal of Korean Association of Computer Education
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• v.6 no.3
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• pp.99-108
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• 2003

This paper indicates limitations of the existing VOD(Video on Demand)-based on-line education systems and presents the design and implementation of Education on Demand (EOD) system as an alternative. EOD system is based on meta information expressed in XML and component technology. Overall system consists of authoring tool. contents server, learning policy system and contents viewer. which are utilized throughout the learning contents life-cycle. EOD system enables automated contents management using meta information exchange methodology that is conformant to the SCORM meta data presentation scheme. In addition, integrated management of interaction and feedback information along with the learning policy system provides customized learning guide for each individual learner. With the development of EOD system, this paper discusses about advanced on-line education system which surpasses existing content-providing-only systems.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.11a
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• pp.313-316
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• 2009

지상파 DMB에서는 양방�� 데이터 서비스를 위하여 MPEG-4 BIFS 규격을 사용하고 있다. BIFS는 콘텐츠의 장면을 구성하는 AV, 이미지, 그래픽, 텍스트 등의 다양한 멀티미디어 객체를 장면상에 표현하고, 사용자로부터 입력을 받아 표현된 객체를 조작하도록 하는 것이 가능하다. 그러나 BIFS가 다양한 형태의 입력장치를 갖는 멀티미디어 시스템에 부합되도록 설계되었지만, 오늘날과 같이 제한적 입력장치를 갖는 휴대 단말에 대한 고려가 결여되어 있다. 문제는 DMB 단말들이 제한적 입력을 가질 수밖에 없기 때문에 사용자가 양방향 데이터 콘텐츠를 조작하는 방법이 일관적이지 못하다는 것이다. 본 논문에서는 이러한 문제를 해결하기 위하여 콘텐츠 제공자와 사용자간의 통일되고 효율적인 콘텐츠 조작을 위해 현재의 BIFS 규격에 KeyNavigator 노드를 추가로 정의하였다. KeyNavigator 노드는 BIFS 콘텐츠에서 휴대 단말의 방향키를 이용하여 BIFS 객체간의 이동이나 BIFS 객체를 선택하는 방법을 제공한다. KeyNavigator노드를 사용함으로써 BIFS 콘텐츠 제공자가 의도하는 바에 따라 콘텐츠를 저작할 수 있고 휴대 단말 사용자에게도 통일되고 효율적인 BIFS 콘텐츠 제어 방법을 제시하는 우수한 효과가 있다.

• Journal of the Korean Society for information Management
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• v.23 no.2
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• pp.81-96
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• 2006

Changes in document delivery service environment such as spread of web-based research information communication and direct communication between users and information providers have considerable effects on document delivery service institutes. Swift advances in information technology have allowed users to receive information on their desktops via web. Web-based document delivery makes the massive scale of reproduction and distribution possible so it needs to protect the copyright holders' rights. This study identifies the current trends and issues of document delivery service environment and reviews electronic document delivery services of foreign countries. Also this study introduces the domestic electronic document delivery service, e-DDS, and evaluates the copyright issues for the service.

• The Journal of Korean Association of Computer Education
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• v.7 no.2
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• pp.67-76
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• 2004

The problems of developing web based adaptive hypermedia for education using XML are discussed in this paper. We define two different markup languages using XML. The one structures the domain model and the another describes the user model. These language can be easily extended and authored, with the result of obtaining a simple methodology for data structuring in the field of web based educational adaptive hypermedia. Also, We have suggested three learning rules that automatically restructures hypertext networks according to their user browsing behavior. The user profile is contained in a user model, while the knowledge about the domain can be represented in the form of a concept based domain model. Accordingly.