• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.29-41
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• 1998

Despite orthodontic treatment(tooth moving) is dynamic act many orthodontists have used mainly static evaluation method for evaluating effectiveness of the orthodontic appliances. They want to find which is better appliance, especially in the treatment results and treatment period when they chose one appliance from sugessted appliances for obtaining same treatment goal. The author and colleagues invented and manufactured new machine for getting information about the relative effectiveness from many suggested orthodontic appliances and we named it Calorific machine. We used this Calorinc machine to find the relative differences about tooth moving mechanism and tooth moving time between the Burstone's PLA(single force mechanism) and Molar-up's PLA(couple mechanism) for correcting the posterior cross bite. We measured the distance of tooth moving on the occlusal X-ray film and recorded the moving time of the anchored(control elctro-thermal tooth) and lingually tipped lower second molars(experimental electro-thermal tooth) and then processed paired t-est by SAS program. The results were as follows. 1. Molar-up's PLA showed more extrusive and horizontal movement than Burstone's PLA at the lingually tipped molar(p=0.0000). 2. There is no finding of tooth movement by Molar-up's PLA at the uprighted molar(p=o.3475) but Burstone's PLA showed a little change(0.2 m) at the same molar(p=0.0001). 3. Burstone's PLA took 17.8 minutes for tooth moving but Molar-up's PLA took only 3.8 minutes(p=0.0001)

• The korean journal of orthodontics
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• v.36 no.3 s.116
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• pp.207-217
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• 2006

Although ceramic brackets have been used widely for improved esthetics during treatment, ceramic brackets have some inherent problems; brittleness, attrition of the opposing teeth and high frictional resistance. This study was performed to understand the frictional resistance of the ceramic brackets, as well as to be a helpful reference for finding the solutions to the problem of frictional resistance. Three different kinds of brackets were used; metal bracket, polycrystalline ceramic brackets with a metal slot to reduce the high frictional resistance and monocrystalline ceramic brackets. The brackets were tested with a $.019{\times}.025$ stainless steel wire with a second order angulation of $0^{\circ}\;and\;10^{\circ}$, and the static and kinetic frictional forces were measured on the universal testing machine. The results of this study showed that the ceramic brackets, especially the monocrystalline ceramic bracket without a metal slot, generated higher frictional resistance than the metal bracket, and the frictional resistance was increased as the angulation between the bracket slot and the wire increased. Therefore, the development of the ceramic bracket with reduced frictional resistance and the prevention of excessive crown tipping during orthodontic treatment will lead to the simultaneous attainment of more efficient and improved esthetic treatment goals.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.379-389
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• 1998

The purpose of the present study was to evaluate the change of tooth mobility following orthodontic tooth movement. Six orthodontic patients which had been treated with edgewise appliance were used. Tooth mobility was measured with Periostest at the time of the removal of orthodontic appliance and 1, 2, 3, 4, 6, 8, 10, 12, 16, 20, 24 weeks after appliance removal. Following results were obtained: 1. Tooth mobility upon the removal of orthodontic appliance showed individual variation while incisor showed greater mobility than the other teeth. 2. Tooth mobility showed continued decrease pattern until 24 weeks after appliance removal. 3. While maxillary incisors showed continued decrease pattern during the study period, the other teeth showed steep decline pattern during the first 12 weeks and gentle slope during the second 12 weeks. 4. The tooth mobility of the maxillary second premolar showed the most typical change in terms of the consistency of the decline. 5. There were no significant differences of tooth mobility between heavy- and light-contacted anterior teeth during experimental period. The results of the present study suggested that periodontal reorganization is not completed even in 24 weeks following orthodontic tooth movement.

• The KIPS Transactions:PartC
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• v.10C no.6
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• pp.779-786
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• 2003

We propose a correction security framework as next generation security technology to provide secure and reliable Internet services. The framework guarantees durability of the services in spite of external attack, intrusion, vulnerability for fault tolerance, and network management technology that covers the set of techniques aimed at providing rapid service recovery. The improvement technology includes system itself improvement and synamic improvement preventing faults from being re-activated, in cooperation with other systems such as vulnerability anaysis system, NMS, ESM. It is expected that our framework will be applied to global networks as well as system alone, and be able to guarantee the network survivability and reliable Internet services.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.1
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• pp.109-114
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• 2009

Purpose: This study was designed to investigate the condition of refractive correction on wearing glasses currently of elementary school children and their accommodative ability in Jinju city. Methods: Objective refraction, subjective refraction, amplitude of accommodation, negative and positive accommodation, accommodative facility, and dynamic retinoscopy were examined on 60 elemenary school children who aged 8~12 wearing myopiacorrected glasses. Results: The condition of refractive corrections was distributed that a case of full correction was 11.7%, a case of low correction with more than 0.8 visual acuity (VA) was 10%, and a case of low correction with less than 0.8 VA was 78.3% in wearing glasses currently. In results from examination of accommodative ability, the number of children having accommodative anomaly is 8 persons (13.3%), they were divided into accommodation insufficiency (4 persons), accommodative facility insufficiency (2 persons), accommodation excess (1 person), and accommodation insufficiency related to ocular function (1 person). Conclusions: It is demanded a periodic inspection of refractive correction to growing children, and the refractive correction after due consideration to accommodative ability is really needed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.8
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• pp.708-714
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• 1990

This paper has proposed a self-tuning controller for tracking reference trajectory by measuring End-point of arm on robot manipulator whose link is light and flexibls, and proved the perforformance of the algorithm proposed through the computer simulation. As an object of control, a flexible robot manipulator with two-links was selected. As for structure of model, it utilized an assume mode shape method with include travity force and derived a dynaics equation by adapting two kinds of vibration mode of each.

• Proceedings of the Korean Society of Computer Information Conference
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• 2010.07a
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• pp.393-396
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• 2010

생산자로부터 고객에 이르는 상품 공급 활동을 관리하는 경영기법인 공급사슬관리(SCM)는 기존의 폐쇄적이고 정적인 환경에서 개방적이고 동적인 환경으로 변화하고 있다. 이러한 변화에 대응하기 위한 실험이나 연구는 부족한 상황이다. TAC SCM은 동적인 SCM 환경에서 다른 경쟁자들과의 경쟁을 통하여 다양한 SCM 전략을 시험할 수 있다. 본 연구에서는 실시간 SCM 환경에서 능동적 할인 전략을 적용한 에이전트를 설계 및 구현하였다. 능동적 할인은 입찰 성공률에 따라 할인율을 변경하여 적용하여 항상 일정한 생산량을 보유할 수 있도록 한다. 본 연구의 실험 결과에서 제안한 에이전트가 서버에서 제시한 Dummy 에이전트보다도 높은 수익과 안정된 생산을 할 수 있음을 보였다.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.227-233
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• 2016

Purpose: On this study, we compared the relationship of dynamic stereoacuity according to the dominant eye, degree of dominant eye, and dominant agreement eye and hand. Methods: For 130 adults (male 70, female 60), mean age of $21.06{\pm}2.21years$ old, dominant eye, degree of dominant eye were measured by objective examination by using the diameter $3.8cm{\times}3.8cm$ thin ring, the dynamic stereoacuity were measured by three-rods test (iNT, Korea). Results: Dynamic stereoacuity according to the dominant eye was center dominant eye without dominance was $14.97{\pm}13.80sec$ of arc, right eye $22.10{\pm}20.01sec$ of arc, left eye $22.31{\pm}20.39sec$ of arc. Dynamic stereoacuity was better when there was no dominance, but the correlation of the dominant eye with dynamic stereoacuity was very low. When Dynamic stereoacuity was separated by in the Center, Mild, Strong, dynamic stereoacuity was $14.97{\pm}13.80sec$ of arc, $20.76{\pm}15.73sec$ of arc and $24.45{\pm}25.60sec$ of arc respectively. The dynamic stereoacuity results were worse when dominance was stonger. However dynamic stereoacuity was better than Center when the degree of dominant eye was rather strong in the dominant left eye. Dynamic stereoacuity according to the dominant eye and hand showed that right eye and hand was $22.63{\pm}20.54sec$ of arc, left eye and hand was $17.36{\pm}10.13sec$ of arc, right eye and left hand was $14.79{\pm}7.05sec$ of arc, left eye and right hand was $22.97{\pm}21.42sec$ of arc so dynamic stereoacuity was comparatively good when the dominant hand was left. Conculsions: Correlation between the dynamic stereoacuity according to the dominant eye, degree of dominant eye was low, however when degree of dominant eye was Center 14.97 sec of arc, Strong 24.45 sec of arc, the dynamic stereoacuity tended to worse when degree of dominant eye was strong. As a result, dominant eye, degree of dominant eye would have to be considered in a more comfortable binocular balance between prescribed for the wearer in binocular vision correction in binocular function such stereoacuity, sports vision training, presbyopia correction and mono vision.

• Journal of the Korean Vacuum Society
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• v.2 no.1
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• pp.1-8
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• 1993

당 연구실에서 개발 제작된 동적교정방법을 이용한 고진공표준기를 사용하여 10-6∼10-3torr 영역에서 가장 널리 쓰이는 spinning rotor gauge와 열음극전리 진공게이지들의 특성을 상품화되어 사용되는 방법대로 측정하여 조사하여 보았다. 게이지들의 직선성, 단기간(15일)에 행해진 반복측정에서의 scattering을 조사하였고 또한 N2, CO, He, H2, O2, Ar 가스에 대한 감도와 압력을 올릴 때와 내릴 때의 hysteresis를 조사하였다.

• Journal of KIISE:Information Networking
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• v.33 no.1
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• pp.91-102
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• 2006

We analyze the performance of MAC-layer Reed-Solomon error recovery in the cdma2000 1xEV-DO Broadcast and Multicast Services (BCMCSs) environment, with respect to the size of the ECB (Error Control Block) and the air-channel condition, and establish the relationship between ECB size, error recovery capacity and service latency. From this we propose an adaptive error recovery scheme which adjusts the size of the ECB to reflect the environment of the mobile nodes so as to meet the required service quality (target bit error-rate), while reducing the latency of real-time applications. Extensive simulation results show the effectiveness of our approach compared to the current static scheme. Proposed adaptive schemes achieves near optimal solution with respect to service latency while satisfying the required service quality.