• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1068-1071
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• 1996

Good shape on flat rolled product is necessary to meet today's customer quality requirement. To meet the increasing demand in quality of strip shape from downstream customers, POSCO has replaced the Automatic Shape Control(ASC) system with the existing one that had used noncontact type measuring system at No.2 Cold Rolling Mill, Pohang works in October, 1995. The strip shape is influenced by the profile, roll crown, bending control, skew control system, as well as work roll cooling system. We have used ASC to adjust those factors in Cold Rolling Mill that could get a satisfactory result, almost less than .+-.5 1-unit deviation from the target shape. However, the downstream customer(i.e. Continuos Annealing Line) wants a good shape not only at the moment of exit of roll bite, but after rolling without tension. In this investigation, the difference will be discussed and how deal with this problem.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.274-279
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• 2009

Reduction Gear Box where from productive site uses the gear with power delivery with high mechanical efficiency of power a deceleration and as the mechanical element union product which has the velocity ratio which is various together is produced with the power occurrence motor and leads gets a high driving force is plentifully used. The above occurs from gear drive issue sound Whine, Noise and Vibration as occurring from the rim process which the gear will bite mainly is delivered with the case etc. gear drive whole which leads the axis and the bearing. The productivity falls with the going straight rate decrease which with like this problem point is caused by with rework the problem point where the cost of production rises under improving boil many kinds analyzed the plan and investigates the resultant acceleration sensor which and a frequency analysis system and was made to apply.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.1025-1028
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• 2002

In this paper, a micro-turning lathe is introduced for micro machining of aluminum rod. To give feed motion, stepwise motion[2] actuators are used instead of the conventional inchworm mechanism. These are consisted of two Piezoelectric ceramics; one is for feeding the slider, and the other is for clamping the slider in the guide way of the body. The guide is V-form. The linearity and positional accuracy of the actuators is good enough far high precision motion. Since the system is more compact than the conventional system using three Piezoelectric ceramics, it is applicable for the micro-machine or MEMS unit. To fabricate the lathe, a small spindle unit with ball bearings of diameter of 10 millimeter is built-up on the top the slider. The motion is feed backed with miniaturized linear encoder attached each axis slider. The diamond tool bite is used for cutting tool. The machining is tried to make small diameter rod. The possible diameter that can be machined in this machine is presented as well as chip formation, surface roughness, and machinability.

• 동력기계공학회지
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• 제6권1호
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• pp.82-87
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• 2002

Not only ferrous but also non-ferrous materials such as aluminum, brass, plastic and woods need cutting operation in recent manufacturing industry. Over the past few years a considerable number of studies have been made on non-ferrous metal cutting. But more study is required to meet various engineering needs. The purpose of this paper is to preform an experiment on the influence of feed-rate adjustment and side rake angle in turning operations from non-ferrous metals. As a result, the surface roughness was reduced when a side-rake angle increases and feed-rate decreases in the case of the plastic, brass, aluminum, and paulownia. Therefore, this papers develop a new type bite that be used to adjust side-rake angle.

• 대한치과보철학회지
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• 제31권4호
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• pp.565-579
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• 1993

This study was accomplished to analyse and compare the occlusal contact patterns during eccentric mandibular movements in adult with normal occlusion. 50 subjects(male 27, female 23), who had natural occlusion and no symptom of temporomandibular disorder, were selected. Teeth contact patterns during mandibular eccentric movements were recorded and the distribution of tooth contacts in maximum intercuspation analysed by T-scan system. And then, tooth contact numbers recored by T-scan and silicone bite registration at centric occlusion were analysed and compared. The results obtained were as follows : 1. Antero-posteriorly, the qualitative center of occlusal contacts in centric occlusion were in the first molar areas, but there was a slight deviation in left-right directions. Thus, distribution of occlusal contacts were not bilaterally symmetric. 2. During the mandibular movements from centric occlusal position to right lateral and left lateral directions, the frequency that maxillary canine joined in lateral guidance was relatively high, but pure canine protected occlusion or pure group function occlusion had small frequency. 3. During mandibular protrusive movement, one or more maxillary central incisors frequently joined in protrusive guidance. 4. During mandibular eccentric movements, working and balancing side premature contact was observered in relatively high frequency. 5. In centric occlusal position, the numbers of occlusal contacts recorded on T-scan were relatively smaller than on silicone bite registration.

• Journal of Oral Medicine and Pain
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• 제45권3호
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• pp.49-55
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• 2020

Purpose: This study investigated the association between the objective indicator of masticatory function assessment and the masseter muscle thickness (MMT) using ultrasound imaging. Methods: A total of 99 subjects (males: 24, females: 75, mean age: 76) were analyzed. The maximum bite force (MBF) was measured with a pressure-sensitive sheet and an image scanner. The mixing ability index (MAI) was calculated by image analysis after asking the subjects to chew a wax specimen. The MMT during rest and clenching were obtained with a diagnostic ultrasound system, and the difference in MMT during rest and MMT during clenching was defined as the difference in masseter muscle thickness (DMMT). Multiple regression analysis was performed to determine the independent variables affecting MBF and MAI. Results: The MBF showed correlation with the number of remaining teeth (β=0.346, p=0.002) and DMMT (β=0.251, p=0.011). The MAI correlated with only the number of remaining teeth (β=0.476, p<0.001). Conclusions: The DMMT reflects the state of masseter muscle contraction, and can be used as a predictor as well as the number of teeth when assessing masticatory function.

• 대한치과보철학회지
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• 제56권1호
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• pp.31-39
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• 2018

구치부 교합의 붕괴는 정상적인 교합평면을 소실 시키고, 과도한 마모를 일으켜 수직고경을 감소시킨다. 감소된 수직 고경은 심미적, 기능적 문제를 일으킬 뿐만 아니라 측두하악관절에 과하중을 야기하고 근신경계 이상을 일으킬 수 있다. 이렇게 붕괴된 교합관계를 개선하기 위해서 수직고경 변경을 고려하여야 하는데 치료 전 정확한 진단과 분석이 필수적이며 새로운 수직 고경에 대한 적응 평가를 함께 하여야 한다. 그리고 과도한 수직피개를 가지는 과개교합 환자는 치아 마모 및 치아정출의 교합 문제를 가지는 경우가 많다. 이러한 사항을 고려해 보았을 때 치아마모로 수직고경이 감소된 과개교합 환자의 문제 해결을 위해서는 전반적인 보철수복을 하여야 한다. 본 증례는 68세 남자환자로 다수 치아의 마모와 상악 구치의 결손부위를 치료하기 위해 수직고경 증가를 동반한 상악 가철성 국소의치 및 상하악 고정성 보철물로 수복한 증례이다.

• 대한치과보철학회지
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• 제33권4호
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• pp.769-779
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• 1995

The understanding the nature of occlusal tooth contacts of natural dentition is important for correct diagnosis and treatment of diseases developed in stomatognatic system. Several investigator have studied the distribution of tooth contacts in maximum intercuspation and have repored contact locations with respect to the tooth position. However, there are few report the variation of the occlusal contact point with change in each head position. This study analysed the number of occlusal contact point with change in each head position. 30 subject(male 17, female 13), who ahad natural occlusion and no symptoms of temporomandibular disorder, were selected. The numbers and patterns of tooth contact were recorded by silicone bite registration on stone model at four different head positions with head anguration gauge(from the supine to the upright position). The results obtained were as follows : 1. The numbers of total occlusal contact point on teeth increased to average 25, 29, 35, 42 points as head angulation was changed from the supine to the upright position against the ala-tragus line, and there was significant difference(P<0.05). 2. In the 19 subject(65%)of total 30 subject, the perforated point of the silicone bite indicated that the locus for the prime contact point moved mesially as the head angulation was changed from the supine to the upright position. 3. On the basis of the fact that the anterior occlusal contact point increase as head angulation changed from the supine to the upright position, we could find that the mandibular position is moved anteriorly.

• 대한치과보철학회지
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• 제57권3호
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• pp.245-253
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• 2019

골격성 3급 부정교합의 악교정 수술로 구강기능과 안모를 개선할 수 있다. 악골부조화가 클수록 술전 교정치료에 의한 치아 이동량이 더욱 커지기 때문에 치주조직에도 큰 변화를 줄 수 있는데, 특히 하악 전치부 치주조직의 파괴가 주로 발생된다. 이 보고는 20년전 골격성 3급 부정교합과 하악전돌로 악교정수술을 받은 후 하악 전치부의 심한 동요 및 반대교합의 해결을 위해 내원한 49세 여성환자의 증례로, Face Hunter, Plane System 및 ARCUS digma II를 이용하여 Top-Down concept의 개인 맞춤형 분석으로 치료계획을 수립하였다. 하악 전치부 발치를 동반한 순측 치조골 성형술과 임플란트 식립 후 즉시임시치관에 의한 즉시부하를 시행하였다. 최종 보철물은 CAD/CAM에 의한 Zirconia 수복물로 제작 후 구강 내에서 나사유지형으로 장착하였다. 6개월이 경과한 현재까지 보철물의 파절과 동요 등은 관찰되지 않았으며, 기능 및 심미적으로 만족스러운 결과를 얻었기에 보고하고자 한다.

• Journal of Korean Dental Science
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• 제4권1호
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• pp.20-25
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• 2011

Purpose: To describe the newly developed Film image transfer system (FITS) for proper positioning of the orthodontic mini-implant in the narrow interdental space and considerations for better application. Materials and Methods: A patient who was planning to have orthodontic mini-implant treatment on the posterior maxilla was recruited to assess the feasibility of FITS. Dental radiographic film and bite record was taken. And then the film image was transferred on the photographic emulsion coated model using transfer light through film projector (enlarger). After exposing the photo emulsion coating on the model, the image was developed with a working solution for a paper developer and fixed. The surgical guide for the mini-implant was fabricated from the transported FITS data. Results: The completed surgical guide was easily placed intraorally, and allowed a simple and rapid placement of the mini-implant. The site of the implant placement was accurate as planned position. Conclusion: In the reported case, The FITS technique represents an effort to minimize risk to the patient and produce consistently good results based upon accurate information about the anatomy of the implant site.