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The Relationship between the Growth of Cranial Base and the Position of Maxilla, Mandible in Complete Unilateral Cleft Lip and Palate Patients (완전 편측성 순구개열자의 두개저 성장과 상,하악골 위치의 상관 관계에 관한 연구)

  • Baek, Jae-Ho;Son, Woo Sung
    • The korean journal of orthodontics
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    • v.30 no.4 s.81
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    • pp.399-411
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    • 2000
  • This study was designed to evaluate the correlations between the morphology and growth of cranial base and the position of nasomaxillary complex and mandible in complete unilateral cleft lip and palate patients. Craniofacial skeletal morphology Pattern was analyzed on the lateral cephalometric radiographs of the 100 subjects of complete unilateral cleft lip and palate group and the 100 normal grower group and each group was divided three sub-groups by age-range like spheno-ethmoidal synchodrosis growing group, spheno-occipital synchondrosis growing group and finished synchondrosis growth group. These data were statistically analyzed to examine significant difference between both groups and between each sub-groups. The results of this study were as follows: 1. In complete unilateral cleft group, the length, thickness of clivus, and the rate of increase in length of clivus showed smaller amount by adolescence. The anterior length of cranial base and the rotation pattern of clivus with age showed no significant difference between two group. 2. In complete unilateral cleft group, nasomaxillary complex were located more posteriorly. This difference between two groups is larger by adolescent group than adult. Vertical position showed no significant difference between two groups. There was significant correlation between the cranial base of cleft group and the horizontal measurements(p<0.01). PtmS showed no significant increment in cleft group. This showed the deficiency of growth in posterior part of maxilla. 3. In mandible, there was no significant difference between normal group and complete unilateral cleft group but articular angle showed significantly smaller in cleft group than in normal one. And the measurements of nasomaxillary complex position, cranial base and the position of mandible had significant correlation(p<0.01).

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A Comparison of pre and post-surgical characteristics in skeletal Class III malocclusion patients using counterpart analysis (구조적 대응체 분석법에 의한 골격성 II급 부정교합 환자의 악교정 수술전후의 비교)

  • Sohn, Byung-Wha;Kyung, Seung-Hyun;Kim, Beom-soo
    • The korean journal of orthodontics
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    • v.34 no.1 s.102
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    • pp.93-107
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    • 2004
  • Enlow's counterpart analysis explains the complex with anatomic and developmental characteristics where craniofacial aspect of Individuals has been developed. Counterpart analysis does not compare individual measurement with the normal value from the average of majority but analyzes by comparison of values that each individual has. In this study we examined surgical changes in skeletal Class III malocclusion patients(male 40, female 40) and compared them with normal occlusion patients using counterpart analysis. The results indicated that : 1. Skeletal anterior-posterior discrepancy was relieved by shortening of the ramus width(B3). 2. The ramus alignment(R3, R4) was displaced posteriorly and the occlusal plane angle(R5) was rotated clockwise. 3. Skeletal Class III pattern was relieved in the post-operative group, but differences in the level of the cranium(R1, R2) was remaining compared to the normal occlusion patients. 4. In the comparison of surgery methods, the two-jaw surgery group presented changes In the maxillary length(A4), ramus alignment(R3, R4) and occlusal plane angle(R5) compared to the one-jaw surgery group, but the differences were not significant. In the past study about Korean skeletal Class m patients, the skeletal characteristics are upward backward rotation of the cranial base, posterior displacement of the maxilla, forward inclination of the ramus and lengthening of the mandibular body, but in this study, skeletal Class m pattern was relieved by shortening of the ramus width and maxillary advancement by orthognathic surgery, because orthognathic surgery is usually performed on limited areas in the maxilla and the mandible.

Optimization of Total Arc Degree for Stereotactic Radiotherapy by Using Integral Biologically Effective Dose and Irradiated Volume (정위방사선치료 시 적분 생물학적 유효선량 및 방사선조사용적을 이용한 Total Arc Degree의 최적화)

  • Lim Do Hoon;Lee Myung Za;Chun Ha Chung;Kim Dae Yong
    • Radiation Oncology Journal
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    • v.19 no.2
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    • pp.199-204
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    • 2001
  • Purpoe : To find the optimal values of total arc degree to protect the normal brain tissue from high dose radiation in stereotactic radiotherapy planning. Methods and Materials : With Xknife-3 planning system & 4 MV linear accelerator, the authors planned under various values of parameters. One isocenter, 12, 20, 30, 40, 50, and 60 mm of collimator diameters, $100^{\circ},\;200^{\circ},\;300^{\circ},\;400^{\circ}C,\;500^{\circ},\;600^{\circ}$ or total arc degrees, and $30^{\circ}\;or\;45^{\circ}$ or arc intervals were used. After the completion of planning, the plans were compared each other using $V_{50}$ (the volume of normal brain that is delivered high dose radiation) and integral biologically effective dose. Results : At $30^{\circ}$ of arc interval, the values of $V_{50}$ had the decreased pattern with the increase of total arc degree in any collimator diameter. At 45 arc interval, up to $400^{\circ}$ of total arc degree, the values of $ V_{50}$ decreased with the increase of total arc degree, but at $500^{\circ}\;and\;600^{\circ}$ of total arc degrees, the values increased. At $30^{\circ}$ of arc interval, integral biologically effective dose showed the decreased pattern with the increase of total arc degree in any collimator diameter. At $45^{\circ}$ arc interval with less than 40 mm collimator diameter, the integral biologically effective dose decreased with the increase of total arc degree, but with n and n mm or collimator diameters, up to $400^{\circ}$ or total arc degree, integral biologically effective dose decreased with the increase of total arc degree, but at $500^{\circ}\;and\;600^{\circ}$ of total arc degrees, the values increased. Conclusion : In the stereotactic radiotherapy planning for brain lesions, planning with $400^{\circ}$ of total arc degree is optimal. Especially, when the larger collimator more than 50 mm diameter should be used, the uses of $500^{\circ}\;and\;600^{\circ}$ of total arc degrees make the increase of$V_{50}$ and integral biologically effective dose. Therefore stereotactic radiotherapy planning using $400^{\circ}$ of total arc degree can increase the therapeutic ratio and produce the effective outcome in the management of personal and mechanical sources in radiotherapy department.

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A FEM comparison study about the force, displacement and initial stress distribution on the maxillary first molars by the application of Asymmetric Head-Gears with the different traction forces (Asymmetric Head-Gear의 견인력의 차이에 따른 상악 제 1 대구치에 나타나는 힘과 변위 및 초기 응력분포에 관한 유한요소법적 비교 연구)

  • Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.31 no.3 s.86
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    • pp.311-323
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    • 2001
  • One of the various mechanics used to treat unilateral Class II malocclusion is head gear with asymmetric face bow. We made the finite element models of unilateral Class II maxillary dental arch and power arm asymmetric face bow. We designed this experiment to observe stress distribution of periodontal ligament, reaction force, and displacement and to understand force system, so to predict the therapeutic effect. On the basis of computerized tomograph of maxillary dental arch of 25 years old male with normal occlusion without extraction and orthodontic treatment history, we made finite element models of maxillary dental arch and periodontal ligament. Then we modified that model to unilateral maxillary Class II malocclusion model of which maxillary left molar displaced mesially. Also, We made finite element model of asymmetric face bow of which right outer bow shorter than left by 25mm(RMO, Penta-FormTM/Medium size, 0.045 inch iner bow, 0.072 inch outer bow). After that, retraction force of 250g, 300b, 350g were applied to maxillary first molar. We concluded as follow. 1. The Net force that both maxillary first molars were received increased as the retraction force increased. Mesially positioned tooth received more force than normally positioned tooth. But, both tooth were received distal force, so distal movement occured. 2. Both tooth received buccal lateral force. In analysis of force element, as the retraction force were increased, force of X-axis at mesially positioned tooth decreased, and force of X-axis at normally positioned tooth increased. so lateral force component moved to the side received less force from more force. 3. There were rotation, tipping with distal movement in maxillary first molar. As retraction force were increased, rotation and tipping also increased. More tipping and rotation occured at the side received more force, that is, mesially positioned tooth. Though it Is small change, displacement of same pattern occur in normally positioned tooth

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The Effects of Organization Characteristics and Relationship Characteristics on Relational Performance: Focused on Mediating Effects of the Dimensions of Trust and Commitment (조직특성과 관계특성이 관계성과에 미치는 영향: 신뢰 차원과 결속 차원의 매개효과를 중심으로)

  • Sung, Min;Oh, Se-Jo
    • Journal of Distribution Research
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    • v.12 no.1
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    • pp.1-31
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    • 2007
  • While trust and commitment are core mediating variables for the purpose of maintaining the long-term relationship, in the context of the characteristics of company and the relationship performance of its members, there have been limited studies which explore as to how each of the dimensions has affects differently. The basic purpose of this study is to examine the relationship between an automobile manufacturer and its agencies. The main purpose of this study is to examine how each different dimension of trust and commitment on the automobile manufacturer has different mediating effects between the characteristics of company(organization characteristics, relationship characteristics) and relationship performance perceived by its agents. Another purpose is to investigate the mechanism by which the relationship performance of the agencies is improved. An empirical study surveying 115 sales office managers at a leading automobile manufacturer in Korea was conducted. An analysis of the collected data indicates that while the characteristics of company have a positive influence on the agencies' relational performance through the mediating role of both trust of benevolence and commitment, agencies' trust of their headquarter's benevolence has a different influence on the dimensions of commitment. Finally, the authors discussed some theoretical contributions and managerial implications. And then, they presented limitations of this study and the future research directions.

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The Relationship Between Knowledge of Oral Health and Actual Condition on Oral Health Care of Diabetic Patients (당뇨병 환자의 구강건강지식 정도와 구강관리실태의 관련성)

  • Kim, Ki-Eun;Han, Ji-Hyoung
    • Journal of dental hygiene science
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    • v.9 no.3
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    • pp.345-351
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    • 2009
  • The aim of this study is understanding the relationship between degree of knowledge and actual condition on oral health care to raise people's attention on oral health care and to develop a oral health care program and respondents are 121 diabetes patients. The conclusion of this study is as follows; 1. In terms of degree of Knowledge, women have better knowledge on dental healthcare than men. People aged between 20 and 50 have relatively good knowledge and the longer patients fight against diabetes the more they know about oral healthcare. 2. In actual oral healthcare condition, only 21.5% of patients use rolling method. Patients who have good knowledge have relatively high frequency of dental treatment. Most patients see dentists for their oral healthcare consultation. 3. All the respondent group hesitate to have dental treatment because of expensive cost. Surprisingly. most patients with good knowledge answers that diabetes has nothing to do with dental disease. 4. In terms of degree of knowledge and having oral healthcare program, diabetes patients who are having programs has better knowledge. 5. Respondent group which has middle level of knowledge in oral healthcare give high marks on oral healthcare but does not show statistical significance.

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Evaluation of nasolabial angle in adult patients with skeletal Class III malocclusion (성인 골격성 III급 부정교합 환자의 올바른 비순각 평가에 관한 연구)

  • Chang, Jun-Ho;Lee, Shin-Jae;Kim, Tae-Woo
    • The korean journal of orthodontics
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    • v.37 no.4
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    • pp.272-282
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    • 2007
  • The purposes of this study were to evaluate the nasolabial angle changes between closed lip position at centric occlusion and relaxed lip position at which the bite is open so that the lips do not touch and to elucidate the significance of the relaxed lip position for dentofacial diagnosis. Methods: The subjects consisted of 60 (35 Males, 25 Females) skeletal Class III malocclusion adult patients (mean age 23.3 years) with anterior crossbite. Results: In Class III malocclusion adult patients, there were significant differences in the nasolabial angle changes between closed lip position and relaxed lip position. Using the cluster analysis, the subjects were divided into three groups according to the pattern of nasolabial angle change: Group 1 (N = 27, 45%, $-8\;{\sim}\;1$), Group 2 (N = 30, 50%, $2^{\circ}\;{\sim}\;17$), and Group 3 (N = 3, 5%, over 18). Conclusion: The results showed that the pattern of the nasolabial angle change between closed lip position and relaxed lip position varies in skeletal Class III malocclusion patients. Thus, relaxed lip position should be taken into account when diagnostic records are obtained and analyzed to accurately to evaluate the facial soft tissues and predict facial esthetics after surgical-orthodontic treatment.

Sodium and Potassium Contents of Denjang (Bean paste) made in Korea and Japan (한국과 일본 된장 중의 sodium과 potassium 함량에 관한 연구)

  • Kim, Chon-Ho;Sumino, Takeshi;Aida, Kuniko;Kaneko, Kentaro;Yamada, Koji;Kaneda, Takashi
    • Journal of the Korean Society of Food Culture
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    • v.8 no.1
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    • pp.73-77
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    • 1993
  • We obtained the following results from determination of the sodium and potassium content contained in Denjang made in Korea and Japan. The mean sodium content of commercial denjang and home made denjang made in Korea and those of Japan are 4181.3 mg/100g, 6015.6 mg/100g and 5082.5 mg/100g, 5890.6 mg/100g, respectively. The mean potassium content of commercial denjang and home made denjang made in Korea and those of Japan are 595.8 mg/100g, 331.3 mg/100g and 365.4 mg/100g, 381.3 mg/100g, respectively. The mean NaCl concentration of commercial denjang and home made denjang made in Korea and those of Japan are 10.62%, 15.28% and 12.91%, 14.96% respectively. The mean Na/K ratios of commercial denjang and home made denjang made in Korea and those of Japan are 7.25, 21.54 and 14.42, 16.14 respectively.

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Study on the Emotional Response of VR Contents Based on Photorealism: Focusing on 360 Product Image (실사 기반 VR 콘텐츠의 감성 반응 연구: 360 제품 이미지를 중심으로)

  • Sim, Hyun-Jun;Noh, Yeon-Sook
    • Science of Emotion and Sensibility
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    • v.23 no.2
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    • pp.75-88
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    • 2020
  • Given the development of information technology, various methods for efficient information delivery have been constructed as the method of delivering product information moves from offline and 2D to online and 3D. These attempts not only are about delivering product information in an online space where no real product exists but also play a crucial role in diversifying and revitalizing online shopping by providing virtual experiences to consumers. 360 product image is a photorealistic VR that allows a subject to be rotated and photographed to view objects in three dimensions. 360 product image has also attracted considerable attention considering that it can deliver richer information about an object compared with the existing still image photography. 360 product image is influenced by divergent production factors, and accordingly, a difference emerges in the responses of users. However, as the history of technology is short, related research is also insufficient. Therefore, this study aimed to grasp the responses of users, which vary depending on the type of products and the number of source images in the 360 product image process. To this end, a representative product among the product groups that can be frequently found in online shopping malls was selected to produce a 360 product image and experiment with 75 users. The emotional responses to the 360 product image were analyzed through an experimental questionnaire to which the semantic classification method was applied. The results of this study could be used as basic data to understand and grasp the sensitivity of consumers to 360 product image.

Oblique Angle Measurements of Flood Velocities Using Microwave Water Surface Current Meter (홍수유속의 전자파표면유속계를 이용한 편각측정)

  • Kim, Young-Sung;Koh, Deuk-Koo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1807-1811
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    • 2009
  • 홍수기 유량측정에 있어서 가장 큰 어려움이었던 유속측정의 정확성을 확보하고 실무자의 안전성을 보장하기 위한 기본 취지에서 1993년 시작된 "대하천 유량 자동측정 설비개발"이라는 연구 주제하에 비접촉식 유속측정 기법에 대한 연구를 수년간 연구개발을 거듭한 결과물인 전자파표면유속계를 1999년도에 상품화하여 현재 국내에서 홍수유속측정 설비로 이용되어지고 있다. 현장에서 유량측정업무에 종사하는 실무자들은 홍수유량측정에 비하여 훨씬 간편함을 몸소 느끼게 되었고, 상품화보급이 시작된지 수년이 지난 상태에서는 더욱 성능이 개선된 전자파표면유속계가 개발되기를 기대하였다. 무엇보다도 홍수기에 유량측정시 기존의 유속측정 방법과 같은 방식으로 각 측선마다 전자파표면유속계를 설치해야하는 번거로움을 피력하였다. 기존의 전자파표면유속계는 하천을 가로지르는 교량위에서 흐름방향에 나란히 측정하는 조건을 고려하였기 때문에 이와 같은 편각인 상태의 유속측정은 검토하지 않았다. 이와 같은 사용자의 요구에 대하여 한국수자원공사에서는 홍수기 유량측정시의 사용자 편의성을 증대하기 위하여 성능개선 작업에 착수하여 편각측정용 전자파표면유속계를 개발하였다. 편각측정의 주된 목적은 전자파표면유속계를 모든 측선에 설치하지 않고 한 지점에서 편각(oblique angle)으로 여러 측선의 유속을 측정함으로써 유속측정의 효율성을 증대시키는 것이다. 전자파표면 유속계에서의 편각 측정은 하천의 유속 방향을 기준으로 정면에서 측정하면 수평 편각이 0도가 되며 좌우로 안테나를 회전하여 움직인 각도가 측정 편각으로 결정된다. 전자파의 물리적 특성 때문에 편각이 증가하면 반사된 신호의 수신 크기가 감소하여 측정이 불가능하게 된다. 이러한 문제를 최대한 극복하는 것이 본 연구의 중점 개선사항이다. 이를 통하여 전자파표면유속계를 교량의 임의 지점에 설치하여 좌우로 편각 $20^{\circ}$에 이르는 범위의 유속을 측정하고자 목표로 하였다. 홍수시의 현장 측정 환경은 열악하기 때문에 정확한 측정을 조건으로 측정자에게 최대한의 편리함과 신속한 측정 환경을 제공해야 효과적인 업무수행이 가능하다. 이러한 편각 측정을 가능토록 하기 위해서는 유속측정시 송신되는 전자파의 출력을 기존의 시스템보다 보다 높게 발사하여야 하며 안테나의 수신감도 및 지향성이 개선되어야 한다. 이를 위해서 안테나 형태에 있어 기존 전자파표면유속계와의 차이점은 기존안테나는 파라볼릭 형상이었으나 신규 제작된 안테나는 평면안테나로 이러한 형태의 개선를 통해 안테나 특성 및 구조적인 차이를 유도하였다. 두 가지 안테나 사양 각각 장단점이 있으나 가장 큰 차이점은 빔폭 특성에서 평면 안테나가 우수하며 수신 감도를 향상시킬 수 있다는 강점이 있다. 특히 Tx/Rx 분리의 평면안테나 구조는 파라볼릭 안테나에서 불가능한 기능으로서 편각측정으로 인한 수신감도의 저하의 문제를 해결하기 위한 개선조치이었다. 성능개선 제작된 편각측정용 전자파표면유속계를 이용하여 일반하천의 홍수유속에 대한 편각측정 실험을 안성천에서 실시한 결과 유속 약 1.7 m/s 인 상황에서 편각 $20\;^{\circ}$ 까지 편각 $0\;^{\circ}$일때와 유사한 측정 성능을 보였다.

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