• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.793-803
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• 2000

Procedures for treatment of molar furcation invasion defects range from open flap debridement, apically repositioned flap surgery, hemisection, tunneling or extraction, to regenerative therapies using bone grafting or guided tissue regenerative therapy, or a combination of both. Several clinical evaluations using regenerative techniques have reported the potential for osseous repair of treated furcation invasions. Regenerative treatment of maxillary molars are more difficult due to the multiple root anatomy and multiple furcation entrances therefore, purpose of this study was to evaluated histologically self-curing glass-ionomer cement and light-curing glass-ionomer cement as a barrier in the treatment of a bi-furcated maxillary premolar. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree II furcation defect was made on maxillary third(P3), forth(P4) and fifth(P5) premolar. 2 month later experimental group were self-curing glassionomer cement and light-curing glassionomer cement. After 4, 8 weeks, the animals were sacrificed by vascular perfusion. Tissue block was excised including the tooth and prepared for light microscope with Gomori's trichrome staining. Results were as follows. 1. In all experiment group, there were not epithelial down growth and glass ionomer cement were encapsulated connective tissue. 2. In 4 weeks experiment I group slighly infiltrated inflammatory cells but not disturb the new bone or new cementum formation. 3. In 8 weeks, experiment groups I, II were encapsulated fine connective tissue. 4. Therefore glass-ionomer cement filling to the grade III maxillary furcations with multiple root anatomy and multiple furcation entrances were possible clinical methods and this technique is useful method for Maxillary furcation involvement.

• 기술혁신연구
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• 제8권1호
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• pp.95-123
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• 2000

The main purpose of this study is to investigate the Korean adults' impressions of the SET(scientist-engineer-technician). The concept of impression is assumed to reflect our significant view of an object better than that of image. That is, the basic assumption is that we tend to behave toward an object, based on its impression which is conceived to be "significant." In September 1999, a national survey for 1,161 sampled adults was conducted to find the Korean general public's impressions of the SET. In addition, a sample of 206 SET persons were surveyed for comparison. Our major finding is that the Korean public has such a good impression that the SET contributes to advanced technology development and human well-being, is very smart and professional, and conducts research and experiment. Many other relevant things such as sources of impression and evaluations of SET professions were also surveyed. Finally, some policy-related implications based on survey results were presented at the end.t the end.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
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• pp.489-492
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• 2002

The objective of the present study were to measure the viscosities of non-Newtonian fluids by the transient flow concept in a capillary tube and to apply to hemodynamic studies and pump performance evaluations. The developed capillary tube viscometer could be used to measure the viscosities of the non-Newtonian fluids for a wide range of the shear rate by a run of experiment in a very short time interval. The measured viscosities of water and blood fur different shear rates were good agreement with those of the well established data. The measured viscosities for muddy water varied with the shear rates.

• 한국의류학회지
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• 제25권3호
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• pp.516-524
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• 2001

This dissertation has been intented to grasp the components of personal colors and classify personal colors. The Method of the study was quasi-experimental. In the experiment to evaluate personal colors, the subjects was 315 male and female college students in Taegu and Kyungbuk area. The evaluations were analyzed by SAS and the methods used were descriptive statistics, cluster analysis, T-test. The results obtained were as follows: First, the major components of subjects personal colors were found to be the colors of skin and hair. Secondly personal colors were classified into three types: warm, cool, and ambiguous. Third types of personal colors tended to be different between men and women.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.474-479
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• 2002

In this research, the relationship between physical measurements and subjective evaluations of floor impact noise in apartment building was quantified by applying the neural network analysis due to its complex and nonlinear characteristics. The neural network analysis was undertaken by setting up L-value, inverse A index, Zwicker parameters and ACF/IACF factors, as input data, which came from the measurements at real suites of apartment building having various sound insulations. The subjective responses from the psychoacoustic experiments were extracted as output data. Then, the reliability of the quantitative prediction for the subjective loudness was evaluated.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제12권2호
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• pp.119-131
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• 2008

The paper considers the computation method in the performance evaluation of cellular network in the phase-type distribution assumptions that the channel holding times induced from mobility are modeled by well-fitted distributions to reflect an actual situation. When ww consider a phase-type distribution model instead of exponential distribution, the complexity of the computation increase exponential even though the accuracy is improved. We consider an efficient numerical algorithm to compute the performance evaluations in cellular networks such as a handoff call dropping probability, new call blocking probability, and handoff arrival rate. Numerical experiment shows that numerical analysis results are well approximated to the results of simulation.

• International Journal of Aeronautical and Space Sciences
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• 제18권2호
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• pp.175-185
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• 2017

This paper presents new differential methods for computing the combined and single dynamic stability derivatives of flight vehicle. Based on rigid dynamic mesh technique, the combined dynamic stability derivative can be achieved by imposing the aircraft pitching to the same angle of attack with two different pitching angular velocities and also translating it to the same additional angle of attack with two different rates of angle of attack. As a result, the acceleration derivative is identified. Moreover, the rotating reference frame is adopted to calculate the rotary derivatives when simulating the steady pull-up with different pitching angular velocities. Two configurations, the Hyper Ballistic Shape (HBS) and Finner missile model, are considered as evaluations and results of all the cases agree well with reference or experiment data. Compared to traditional ones, the new differential methods are of high efficiency and accuracy, and potential to be extended to the simulation of combined and single stability derivatives of directional and lateral.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2002년도 춘계학술대회논문집
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• pp.163-168
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• 2002

The road sign in dynamic traffic system is an important element which affects on human cognitive performance on driving. Web-based vision system simulator was developed to examine the cognition time of the road sign in dynamic environment. This experiment was designed in within-subject design with two factors; vehicle speed and the amount of information of the traffic sign. It measured the cognition time of the road sign through two evaluation methods; the subjective test with vision system simulator and computational cognitive model. In these two evaluations of human cognitive performance under the dynamic traffic environment, it demonstrated that subject's cognition time was affected by both the amount of information of traffic sign and driving speed.

• 아동학회지
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• 제25권4호
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• pp.177-190
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• 2004

Training for mothers and children first included information on water, ground, and air pollution, saving energy, and reducing trash. In the second phase, the family followed steps outlined in an environmental preservation guidebook. The experiment was of 16 weeks duration, conducted with 120 subjects, comprised of sixty 4-year-old children and their mothers. Measures included environmental preservation knowledge and the actual practice of environmental preservation on the part of the subjects. Mothers performed self-evaluations while teachers measured the children. SPSS was used for data collection and analysis. The results of this study indicate that the program increased perceptions on environmental preservation and the actual practice of the experimental group. The program application also resulted in meaningful co-relationships between perceptions and practice and between mothers and their children.

• 정보처리학회논문지C
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• 제12C권7호
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• pp.1047-1056
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• 2005

기존 데이터 방송 시스템은 수신 단말이 완전한 애플리케이션 데이터를 획득하지 못한 경우 반복적으로 방송 애플리케이션 데이터 전체를 다운로드하는 매커니즘을 가지고 있다. 이 방식은 다운로드 시간이 길어지는 요인이 된다. 이러한 문제점을 개선하기 위해 본 논문은 리턴 채널을 활용하여 누락된 방송 애플리케이션 데이터를 효과적으로 다운로드하는 기법을 제안하고 실험을 통하여 제안된 기법의 비교 성능 평가를 보인다.