• Title/Summary/Keyword: Joint development

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Treatment strategies on Class III malocclusion based on Long term follow up study (III급 부정교합의 치료전략)

  • Sung, Jae-Hyun
    • The korean journal of orthodontics
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    • v.26 no.2 s.55
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    • pp.125-139
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    • 1996
  • The author obtained some useful information for the class III treatment from long term observation on the growing patients with class III malocclusion. 8 patients were selected for this study and presentation. From these observation so far my conclusions might be as follows: First in the early correction of the anterior crossbite, considerable forward growth changes were observed in the maxilla Second, as for the growth modification of jaws by orthopedic treatment only limited effects were recognized from the long-term observation Thrid, at early age of patients with anterior crossbite, any data couldn't make me predict the stability after treatment on the long-term basis. Fortunately, however, genial angle showed a marginal possibility of it prediction. Fourth, at an advanced age/ retraction orthopedic force on the mandible and the rapid change in the mandibular position may cause some trouble in the T.M.joint. Finally, the followings are recommendable. As for the anterior crossbite, correct it early as possible, and use orthopedic force under the age of ten. Do not enter the phase II treatment directly. Just wait and observe until the growth were almost completed, focusiong on some important factors such as airway problem, tongue position, and third molar development. Of course, these factors may have some effects on the mandibular growth. for the female, at the age of around 14 years old and the male, around 17 years old, make a final decision whether the patients will continue to be treated orthodontically or surgically Thereby, (I think) the relapse and retreatment problem after treatemnt we have observed so far might be minimized. Furthermore, the active treatment time may be also reduced.

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AN EXPERIMENTAL STUDY ON THE MORPHOLOGIC CHANGES OF RAT MANDIBLE FOLLOWING OCCLUSAL INTERFERENCE (교합장애에 의한 백서 하악골의 형태적 변화에 관한 실험적 연구)

  • Kim, Jae-Seung;Chung, Kyu-Rim
    • The korean journal of orthodontics
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    • v.24 no.2
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    • pp.275-294
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    • 1994
  • The occlusal interference during adolescent period makes some effects on growth and development and morphological changes. And so, if we could predict the the timing and results of orthodontic treatment who have occlusal interference during adolescent period, it may be helpful for diagnosis and treatment planning of orthodontic treatment. For about those, the purpose of this study was to evaluate the effects of the posterolateral displacement by the metal casting crown with inclined pathway on the mandibular condyle and morphologic changes of mandible in the rat. The experimental animals were thirty six Sprague-Dawley male rats of 8 weeks old. Eight of them was used as control group, and experimental group 1 ( continuous appliance wearing group ) was composed of sixteen and experimental group 2 ( appliance removal group after worn the appliances during 3 months ) was composed of remaining twelve. The animals of experimental grouop 1 were sacrificed after 1, 2, 3, 6 months from beginning of the experiment and experimental group 2 were sacrificed 1, 2, 3 months after removal of the appliance from worn the appliance during 3 months. Both of mandible and temporomandibular joint were observed histologically and radiologically. The results were as follows : 1. In experimental group 1, the mandibular length and lower posterior height were decreased with experimental period, while the lower anterior height was increased, and the curvature of lower incisors and lingual inclination of anterior alveolar bone were profound as compared with control group. 2. In experimental group 1, both of the thickness of the condylar cartilage were thinned in the posterosuperior region, and this phenomenon was more prominent on right than left in 3-Mo experimental period and both sides were marked thinned in 6-Mo experimental period. 3. In experimental group 2, the lower anterior height was low and lower posterior height was high as compared with experimental group 1, and the curvature of lower incisors and lingual inclination of anterior alveolar bone were recovered to control group. 4. In experimental group 2, both of the thickness of the condylar cartilage were thickened in the posterosuperior region, and this phenomenon was more prominent with experimental period. 5. In experimental group 2, the mandibular length was short, lower anterior height was hight, the curvature of lower incisors were profound, and in histologically, both of the thickness of the condylar cartilage were thickened in the posterosuperior region as compared with control group. As shown above, the occlusal interfemce affected the condylar cartilage, curvature of lower incisor, inclination of anterior alveolar bone, mandibular length, and anterior and posterior height. When the interference was removed, significant recover was found in condylar cartilage, mandibular length, and posterior height. Although no significance was found, other items of measurement showed trends for recovery.

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Occlusal Analysis in the Policemen with Temporomandibular Disorders Using T-scan II System (경찰 종사자의 측두하악장애환자에서 T-scan II System을 이용한 교합분석)

  • Lim, Hyun-Dae;Jung, Seung-Ah;Lee, You-Mee
    • Journal of Oral Medicine and Pain
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    • v.31 no.4
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    • pp.365-373
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    • 2006
  • This study suggested correction of excessive mouth opening or maximum occlusal contact to analyse occlusal contact time, occlusal contact number and force through evaluation of occlusal pattern in policemen with temporomandibular disorders. The community of policemen influence on temporomandibular disorder's development and progress due to other condition of mouth opening and maximal occlusal contact. Repeated training or changes of usual life style may cause imbalance of stomatognathic system including the masticatory muscle, then develop or aggravate pain of temporomandibular joints and associated structures. This study uses T-scan II system(Tekscan Co., USA) for evaluation on occlusal pattern may influence temporomandibular disorders, and then the subjects take a sensor at 20 mm opening for maximal occlusal contact force. The policemen with temporomandibualr disorders get more long time on maximum contact timing, more short on end contact timing, and more force on end contact force than general society's. So they get closure of mouth with more short time and more force, then transfer remaining load to temporomandibular joint. There are no statistically significances between affected side and occlusal pattern of occlusal contact time and force. There are Left -right dental arch imbalances seems on Rt. dental arch if affected side is right and Lt. dental arch if affected side is left. In above results, It's worth due consideration that policemen with temporomandibular disorders get more smooth mandibualr movement and less force on maximal occlusal contact position.

Economic Analysis with Development of Rapid Setting Alumina-based Binder for Road Repair (알루미나계열 속경성 도로 보수재료 개발에 따른 경제성 분석)

  • Yang, Hee-Jun;Yang, Min-Jae;Hong, Sung-In;Ann, Ki-Yong
    • Journal of the Korea Concrete Institute
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    • v.29 no.1
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    • pp.3-10
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    • 2017
  • In case of Korea highways, about 60% of highways are paved by concrete and more than 50% of them were repaired due to reduction in required performance such as damage in pave or joint and delamination of cover pavement. However, repairing old material in such structure generally costs a lot of money and induces difficulty in maintenance. Thus, enhanced material for ensuring economic efficiency should be developed. The present study designed concrete mixtures with 3 levels of replacement using OPC (0, 10, 20%) in calcium aluminate cement and to evaluate material performance for load pavement, experimental works for setting time, compressive strength and flexural strength were carried out on those materials. As a result, 20% replacement for OPC was determined as an optimized material in terms of required physical performance and its unit price. Moreover, to determine cost in load pavement economy analysis using a program (CA4PRS) was conducted with widely used paving materials. Result showed that application for 20% replacement for OPC was the most efficient in economical aspect, arising from 4.052 and 1.577 billion won for total construction and user cost, respectively.

A Study on the Effective Method to Producing Data for The ROKA Live Fire Training Range Safety (한국군 실 사격 훈련간 효율적인 안전지대 데이터 구축 방안 연구)

  • Lee, June-Sik;Choi, Bong-Wan;Oh, Hyun-Seung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.38 no.3
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    • pp.64-77
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    • 2015
  • An effective method for produce munitions effectiveness data is to calculate weapon effectiveness indices in the US military's Joint Munitions Effectiveness Manuals (JMEM) and take advantage of the damage evaluation model (GFSM) and weapon Effectiveness Evaluation Model (Matrix Evaluator). However, a study about the Range Safety that can be applied in the live firing exercises is very insufficient in the case of ROK military. The Range Safety program is an element of the US Army Safety Program, and is the program responsible for developing policies and guidance to ensure the safe operation of live-fire ranges. The methodology of Weapon Danger Zone (WDZ) program is based on a combination of weapon modeling/simulation data and actual impact data. Also, each WDZ incorporates a probability distribution function which provides the information necessary to perform a quantitative risk assessment to evaluate the relative risk of an identified profile. A study of method to establish for K-Range Safety data is to develop manuals (pamphlet) will be a standard to ensure the effective and safe fire training at the ROK military education and training and environmental conditions. For example, WDZs are generated with the WDZ tool as part of the RMTK (Range Managers Tool Kit) package. The WDZ tool is a Geographic Information System-based application that is available to operational planners and range safety manager of Army and Marine Corps in both desktop and web-based versions. K-Range Safety Program based on US data is reflected in the Korean terrain by operating environments and training doctrine etc, and the range safety data are made. Thus, verification process on modified variables data is required. K-Range Safety rather than being produced by a single program, is an package safety activities and measures through weapon danger zone tool, SRP (The Sustainable Range Program), manuals, doctrine, terrain, climate, military defence M&S, weapon system development/operational test evaluation and analysis to continuously improving range safety zone. Distribution of this K-range safety pamphlet is available to Army users in electronic media only and is intended for the standing army and army reserve. Also publication and distribution to authorized users for marine corps commands are indicated in the table of allowances for publications. Therefore, this study proposes an efficient K-Range Safety Manual producing to calculate the danger zones that can be applied to the ROK military's live fire training by introducing of US Army weapons danger zone program and Range Safety Manual

The Characteristics of Pre-Service Secondary Science Teachers' Curriculum Design for Teaching in Science Museum (과학관 활용 수업을 위한 중등 예비과학교사의 교수 설계에서 나타나는 특징)

  • Yang, Chanho;Bae, Yujin;Noh, Taehee
    • Journal of The Korean Association For Science Education
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    • v.35 no.1
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    • pp.95-107
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    • 2015
  • In this case study, we investigated the characteristics of pre-service secondary science teachers' curriculum design for teaching in science museums. Three pre-service secondary science teachers at a college of education in Seoul participated in this study. We have observed and recorded their teaching practices in science museums, collected all of their teaching materials, and conducted semi-structured interviews before and after teaching. All the data collected were analyzed by using the constant comparative method. The analyses of results revealed that the pre-service teachers structured their teaching in a series of pre-visit, during-visit, and post-visit as continuous activities. They attempted to reinforce students' learning experiences during the visit by providing post-visit activities, and also properly considered the principle that activity should be personally meaningful or relevant to students. However, they lacked the perceptions as well as the practical knowledge of reducing student's novelty of the science museum by providing activities prior to the visit, encouraging to engage in joint productive activities, promoting diverse social interactions, and providing students with choices and controls on their learning. On the bases of these results, we made some suggestions in pre-service teacher education for the professional development of teaching in science museum.

Proposal's analysis of major fishing countries and Countermeasures under WTO/DDA (각국 제안서에 따른 WTO/DDA 수산보조금 대응 방안)

  • Lee, Kwang-Nam;Seo, Byung-Kwi
    • Journal of Fisheries and Marine Sciences Education
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    • v.17 no.3
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    • pp.324-339
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    • 2005
  • The WTO/DDA Negotiation on the Fisheries Subsidies started by DDA(Doha Development Agenda : 2001.11)at early 2002 has been held about 20 times until the fist half of 2005. The Negotiation will be terminated until the end of 2005 but now, it is impossible to predict the exact conclusion of the Negotiation. There is a sharp conflict of opinion on the WTO/DDA Negotiation on the Fisheries Subsidies between FFG(Fish Friends Groups : USA, New Zealand etc) and Anti-FFG(Rep. Korea, Japan etc). The Fisheries Subsidies is regulated by the WTO/DDA Negotiation that regulates on the subsidies of industrial products, fisheries products, forest products. Considering the progress of the WTO/DDA Negotiation on the Fisheries Subsidies, Guidelines for the Fisheries Subsidies Negotiation were established in Doha Ministerial Declaration at 2001 and a necessity of a special regulation on the Fisheries Subsidies has been discussed from 2002 to 2004. After june, 2004, the Negotiation was proceeding as Rep. Korea, Japan and Taiwan agreed with discussing a special regulation on the Fisheries Subsidies and At 1st, August, 2004, they reached an agreement on a necessity of a special regulation on the Fisheries Subsidies. At Feb, 2005, discussion was suspended because of presenting the joint proposal from 3 countries(Rep. Korea, Japan and Taiwan) and now discussion on the Fisheries Subsidies is giving the first consideration to classification of prohibited/non-actionable subsidies, S&D of a developing countries, small fisheries, problems of farming, grace period etc. From now on, Considering the 18th~the 20th negotiations, it is expected that discussion of fisheries subsidies regulation including property and range of prohibited/non-actionable subsidies, S&D of a developing countries, a definition of small fisheries is accelerated. In this point of view, this paper analyzed and arranged every country's proposals holding our own position and took a survey to fishermen and fisheries experts about prohibited/non-actionable subsidies. In addition, this paper intends to suggest the way of future-negotiation and provides essential data to help government's policy making through analyzing prohibited/ non-actionable subsidies, farming subsidies, S&D of a developing countries, small scale fisheries.

Railway Governance and Power Structure in China

  • Lee, Jinjing
    • International Journal of Railway
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    • v.1 no.4
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    • pp.129-133
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    • 2008
  • Over the last $15{\sim}20$years, many countries have adopted policies of railway privatization to keep up with increasing competition from road and air transport. Although each country and case has its own history, market characteristics, political context as well as administrative process, railway privatizations (including railway restructure, concession etc.) in the west usually are accompanied with the establishment of new regulatory regimes. Therefore, railway governance has been innovating towards an interaction of government, regulator, industry bodies, user groups, trade unions and other interested groups within the regulatory framework. However, it is not the case in China. Although China had seen a partial privatization in some branch lines and is experiencing a much larger-scale privatization by establishing joint-ventures to build and operate high-speed passenger lines and implementing an asset-based securitization program, administrative control still occupies absolutely dominant position in the railway governance in China. Ministry of Railway (MOR) acts as the administrator, operator as well as regulator. There is no national policy that clearly positions railway in the transportation network and clarifies the role of government in railway development. There is also little participation from interested groups in the railway policy making, pricing, service standard or safety matter. Railway in China is solely governed by the mere executive agency. Efficiency-focused economic perspective explanation is far from satisfaction. A wider research perspective from political and social regime is of great potential to better explain and solve the problem. In the west, separation and constrains of power had long been established as a fundamental rule. In addition to internal separation of political power(legislation, execution and jurisdiction), rise of corporation in the 19th century and association revolution in the 20th century greatly fostered the growth of economic and social power. Therefore, political, social and economic organizations cooperate and compete with each other, which leads to a balanced and resonable power structure. While in China, political power, mainly party-controlled administrative power has been keeping a dominated position since the time of plan economy. Although the economic reform promoted the growth of economic power of enterprises, it is still not strong enough to compete with political power. Furthermore, under rigid political control, social organizations usually are affiliated to government, independent social power is still too weak to function. So, duo to the limited and slow reform in political and social regime in China, there is an unbalanced power structure within which political power is dominant, economic power expanding while social power still absent. Totally different power structure in China determines the fundamental institutional environment of her railway privatization and governance. It is expected that the exploration of who act behind railway governance and their acting strength (a power theory) will present us a better picture of railway governance as a relevant transportation mode. The paper first examines the railway governance in China and preliminarily establishes a linkage between railway governance and its fundamental institutional environment, i.e. power structure in a specific country. Secondly, the reason why there is no national policy in China is explored in the view of political power. In China, legislative power is more symbolic while party-controlled administrative power dominates political process and plays a fundamental role in Chinese railway governance. And then, in the part three railway finance reform is analyzed in the view of economic power, esp. the relationship of political power and economic power.

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Group-Based Frequency Hopping Scheme for Improving Multi-Net Performance of Link-16 Waveform with Limited Frequency Band (제한된 주파수 대역에서 Link-16 웨이브폼의 멀티넷 성능 향상을 위한 그룹 기반의 주파수 도약 방식)

  • Yu, Jepung;Lee, Kyuman;Baek, Hoki;Lim, Jaesung;Kim, Jongsung;Choi, Hyogi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.1
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    • pp.110-121
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    • 2016
  • Link-16 is a representative TDL operated by US air force and NATO and supports structure of Multi-net. Under Multi-net, military operation can be conducted effectively since terminal nodes in Link-16 hop over total frequency band simultaneously. As air traffic is rapidly increasing, new aeronautical system is introduced or existing system should be expanded to accommodate increasing air traffic and frequency band assigned for operating this system is scarce. It is scheduled to implement frequency remapping to solve frequency scarcity. With limited frequency band for operating Link-16, as frequency remapping is implemented, degradation of Multi-net performance can happen since multiple access interference in Link-16 is increasing so it is difficult to conduct multiple military operations. Thus, Group-based frequency hopping scheme is proposed to solve this problem. We verified the performance of the proposed scheme is improved.

Study of emoticon as an emotional sign under the digital communication environment (디지털 커뮤니케이션 환경에서 감성기호로서 이모티콘에 관한 연구)

  • 조규명;김경숙
    • Archives of design research
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    • v.17 no.1
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    • pp.319-328
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    • 2004
  • The communication environment made by digital technologies has made it possible to exchange information and deliver messages fast and easily among people of various classes in virtual space beyond time and space. Net-generation, who is accustomed to this virtual space, couldn't be satisfied with the linear text-oriented language any more, and began to make signs by use of computers in order to differentiate itself from others and to express its desires. Among the signs, emoticon created by joint of popular culture and digital communication centering around young generation is a new visual sign and emotional sign that can deliver a sender's feelings contained in a message. This paper has studied social phenomena, their relationships with emoticon and background of its creation through documentary review of media development, changes in the communication environment and popular culture. Furthermore, it has analyzed the meaningful action and roles of emoticon as a sign in terms of semiotics and also, studied a possibility of using emoticon as a new emotional sign. The study results say that emoticon can play the roles of a non-linguistic sign just like general signs that make mutual exchange through meaningful action, and also that it can be used to effectively deliver messages not only in virtual space, but also in advertising, posters, magazines and CI. However, emoticon is better at emotional expressions yet than other textual signs or visual signs, but in order to position itself as a universal and popular sign, emotional expressions should be clear, any difference in understanding messages should be removed, and message delivery should be more efficient.

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