• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.170-177
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• 2020

This study examined the clamping force control method and the braking performance test results of an electromechanical brake (EMB) using braking test equipment. Most of the studies related to EMBs have been carried out in the automotive field, dealing mainly with the static test results for various control methods. On the other hand, this study performed a dynamic performance evaluation. The three-phase interior permanent magnet synchronous motor (IPMSM) was applied to drive the actuator of the EMB, and the analysis was verified by JMAG(Ver. 18.0), which is finite element method (FEM) software. The current control, speed control, and position control were used for clamping force control of the EMB, and the maximum torque per ampere (MTPA) control was applied to the current controller for efficient control. The EMB's emergency braking deceleration performance was tested in the same way as conventional pneumatic brake systems when the wheel of a train rotates at 110 km/h, 230 km/h, and 300 km/h. The emergency braking time, with the wheel stopped completely at the maximum rotational speed, was approximately 73 seconds. The similarity of the braking time and deceleration pattern was verified through a comparison with the performance test results of the pneumatic brake system applied to the next generation high-speed railway vehicle (HEMU-430X).

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.1
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• pp.53-62
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• 2014

Human has noticed a beautiful natural scenery and appreciated it as a scenic site by giving meaning to it and evaluating it. How the beautiful natural scenery was appreciated as a scenic site depends on natural features, social and cultural environments, and the current of the times. Mt. Jiri is the highest mountain in inland South Korea and keeps ancestors' history and culture intact. Joseon Dynasty literary men frequently mentioned Mt. Jiri as a tourist attraction where they could pursue and share their studies against its beautiful natural scenery. The countless literary men visited Mt. Jiri and some of them left their journeys as travelling records. This research aimed at apprehending travel routes of Chunwang Peak of Mt. Jiri based on the contents of travelling records and investigating the scenic site value of scenic resources as the literary men in Joseon Dynasty recognized. The scenic resources of Mt. Jiri were related to the change of the reason or motivation of person who climbed and it should be noted that there was a change of reason or motivation in climbing Mt. Jiri from a following of master's paths to discovery of a new trails. Thus, even if there was a difference in reason or purpose of natural scenic beauty, the concept of scenic sites of the past and the present day should be included into the extended meaning of scenic sites. This research aimed the routes of well-known literary men need to be developed as programs utilizing "the concept of ancient sages' footprints" and the development of these contents shall be used for vitalization and self-support of a regional economy.

• Journal of Biomedical Engineering Research
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• v.20 no.4
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• pp.479-484
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• 1999

본 연구에서는 사람의 턱 운동과 턱 사이에 작용하는 힘(혹은 압력)을 그대로 나타낼 수 있는 저작로봇을 개발하는 것을 궁극적인 목표로 한다. 이러한 저작로봇이 개발되면, 치과의사가 환자의 턱운동에 나타나는 병변을 진단하고 치료하는데 큰 도움이 될 것으로 사료된다. 또한 , 본 연구에 채택한 병렬기구(parallel mechanism)에대한 순기구학적( forward kinematics)분석은 일반적인 병렬기구의 실계에도 응용될 것으로 기대된다. 본 연구진이 1차적으로 설계한 모델은 베이스와 플랫폼(platform), 그리고 이 둘을 연결하는 3개의 다리로 구성되어 있다. 다리와 플랫폼은 3자유도의 관절로 다리와 베이스는 1자유도의 경첩 관절로 연결되어 있으며, 이 3개의 경첩 관절은 베이스 위의 수평면에서 직선을 따라 움직인다. 경첩 관절의 수평 변위와 세 다리의 길이가 주어졌을 때 플랫폼의 위치와 오리엔테이션을 구하는 순기구학의 해( 解)를 계산해내는 알고리즘을 개발하였다. 이 알고리즘의 특징은 매 순간 오차를 계산하여 이 오차가 줄어드는 방향으로 나아가도록 시간간격(time step)을 조절하는 것이다. 본 알고리즘은 현재 가장 보편적으로 사용되고 있는 뉴튼-렙슨 방법에 비하여 3가지 장점을 나타내고 있다. 우선 , 초기치(initial guess)에 관계없이 수렴한다는 것이다. 또한, 본 알고리즘은 뉴튼-렙슨 방법에 비하여 수렴속도가 훨씬 빠르며, 연산 시간이 매우 짧아져 실제적인 실시간 적용에 적합하다. 마지막으로, 뉴튼-렙슨 방법에서는 여러 개의 해 가운데 어느 곳으로 수렴할 지 예측 할수 없으나 본 알고리즘에서는 초기치에 가장 가까운 해로 수렴한다. 이러한 순기구학의 다중성(multiplicity)문제를 해결하기 위하여 두 개의 조건을 제시하였으며, 이를 적용한 시뮬레이션 결과에 의하면 항상 원하는 해(true solution)에 수렴할 수 있었다.발생량의 감소를 기대 할 수 있는 친환경기술로 유지관리비를 최소화할 수 있는 장점이 있었다. 않은 사람들 중 미래의 검진실행의지에 건강소식지가 영향을 미친 경우는 48.7%였다. 보건교육을 받은 후 유방암 자가검진 실천율은 사업군에서 53.9%로 받기 전의 27.3%보다 증가하였으나 대조군의 경우는 별 차이가 없었다. 연령별로는 60대가 가장 높았고 사업군에서 검진율의 증가분은 30대가 가장 컸다. 교육수준별로는 사업군은 고졸이, 대조군은 전문대졸이 가장 높았고 사업군에서 검진율의 증가분은 고졸에서 가장 컸다. 보건교육 후 유방암과 관련된 건강지식의 정도는 사업군이 3.7점으로 대조군보다 유의하게 높았으며, 유방암 자가검진법을 실천하는 사람들의 동기는 ‘일반 대중매체의 영향’이 가장 많았으며 건강소식지가 동기인 경우도 20.4%였다. 사업군에서 건강소식지가 유방암 자가검진법 실천에 영향을 미친 경우가 79.6%였으며 유방암 자가검진법에 관한 보건교육을 받고 실천하지 않은 사람들 중 미래의 실천의지에 건강소식지가 영향을 미친 경우는 43.6%였다. 이상의 소견에서 지역주민을 대상으로 인쇄매체를 통한 보건교육은 인쇄물만으로도 쉽게 실천 할 수 있는 유방암 자가검진법이 가장 효과적이었으며, 자궁암검진에 관해서도 검진을 받을 수 있도록 지역사회의 보건의료의 하부구조를 정비하여 제도적 장치를 마련하고 정보를 제공한다면 자궁암검진 실천율도 증가할 것이다.고 12.9% 의 발달율을 보여 유의적인 차이를 보이지 않았다. 이상의 결과로 보아 핵이식 수정란을 효율적으로 생산하기 위하여 수핵난자의 세포질에 ionomycin 과 DMAP 의 혼합처리로 탈핵난자의 활성화를 유도하는 것이 효율을 증진시킬 수 있었다고 본다. 또한 공핵수정란을 수정 후 90시간과 114시간 개별 배양하여 할구를 공핵체로 핵이식에 이용하였을 때도 그룹배양에 비하여 효율이 떨어지지 않음을 알 수 있었으며, 수정란의 할구

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.403-414
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• 2018

The purpose of this study was to investigate the knowledge and satisfaction of tooth bleaching. From June 1st, 2017, 328 patients who visited a dental clinic in Ulsan Metropolitan City for two weeks were asked to do a self - filling questionnaire. As a result of the study, the tooth bleaching satisfaction according to tooth bleaching knowledge was not statistically significant (p<0.05), and the highest(8-10) degree of satisfaction was 3.86 when the knowledge of tooth bleaching was high, and the lowest(0-3) was 3.00. The tooth bleaching satisfaction according to general characteristics was significantly different in age and gender. The score of women were 3.74 and higher than men's 3.11 The tooth bleaching experience and tooth bleaching satisfaction were statistically significant (p <0.05) and professional tooth bleaching (4.41) was higher than OCT bleaching (2.64). Also, when the tooth bleaching was done by the invitation of the hospital, it was higher than the case of experiencing tooth bleaching through media advertising. Therefore, the satisfaction of tooth bleaching is required not only for general characteristics but also for tooth tooth bleaching, and it is influenced by tooth bleaching method and tooth bleaching motivation. These factors may be useful to establish a treatment plan to improve the satisfaction of tooth bleaching.

• Geophysics and Geophysical Exploration
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• v.20 no.1
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• pp.43-48
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• 2017

The applicability of refraction survey has been tested using a wave glider widely used in long-term ocean observations around the world. To record seismic refractions, a single channel streamer with metal weight and a seismic recording system were mounted on the wave glider. We used GPS precise time synchronization signal and radio frequency (RF) communication to synchronize shot and recorder triggers and to control acquired data quality in real time. When the wave glider is positioned close to the set point, a 2,000 J sparker is exploded along the designed track at 2 second intervals. Through the test survey, we were able to successfully acquire refractions from the subsurface.

• Journal of dental hygiene science
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• v.6 no.4
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• pp.243-249
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• 2006

The purpose of this survey research was to investigate the satisfaction and the factor of stress of 183 dental hygienic students for the dental clinical training who were at 3 colleges which were located in Incheon-city and Kyunggido. This survey was carried out from 12th of September to 19th of October and analyzed using SPSS WIN 12.0. As a result of analysis, the following conclusion were obtained. 1. 86.3% dental hygienic students for satisfaction for the major, 75.9% for training, and 91.8% for future occupation reflected as more than good. 2. In case of the factor of stress, Ideal and value was found out as $3.54{\pm}1.23$ and personnel relationship as $1.74{\pm}1.20$. 3. In case of satisfaction according to general characteristics, there were more or less significant differences according to motive of department choice (P = 0.003) for satisfaction of the major and motive of department choice (P = 0.036) for satisfaction of future occupation. 4. Correlation among each satisfactions showed as the more they were satisfied with the major, the more they were satisfied with training, moreover, they were also satisfied with future occupation. 5. For factor of stress affecting to satisfaction for training, role and ideal and value were showed as affecting variables.

• Journal of dental hygiene science
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• v.5 no.4
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• pp.239-244
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• 2005

The purpose of this study was to delve into the work values of dental hygiene students. The subjects in this study were 465 students who attended three different colleges in Gyeonggi province. After a survey was conducted, the collected data were analyzed with SPSSWIN 12.0 program. The findings of the study were as follows: (1) As for the type of work values, the largest group of the students investigated attached importance to pay and reputation, as they gave a mean of 4.18 to those things. In detail, they put the most emphasis on economic compensation since they gave it a mean of 4.42. (2) Regarding their detailed outlook, there was significantly strong positive correlation between their view of achievement and of competency, between their view of economic compensation and of position, and between their view of recognition and of position. (3) As to the impacts of their general characteristics, their work values in pursuit of self-realization was statistically significantly different according to their motivation of choosing dental hygiene(P = .042). Their school(P = .011), academic school year(P = .023), actual work experience as a dental hygienist(P = .045) and motivation of choosing dental hygiene (P = .023) made a statistically significant difference to their contribution- oriented view of occupation. And their work values that accentuated pay and reputation varied statistically significantly with their school(P = .000) and academic school year(P = .000).

• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.163-171
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• 2005

Current roads were designed and constructed based on the design criteria and thus those were overly simplified drivers' needs. The road criteria do not suggest the desirable range of the design values but suggest the minimum requirements for the road design. Therefore, a completed road design based on the design criteria does not always guarantee the best design in terms of safety and it sometimes violates drivers' expectation. Therefore, the ROSSAV(ROad Safety Survey and Analysis Vehicle) is being developed by the KICT to evaluate road safety and increase driving safety. In this paper, the image capture system was described in detail. The image capture system is consisted of two front view cameras, two side down-looking cameras and a synchronization device. Two front view cameras were used to take a picture of road and road facilities at the driver's viewpoint. Also, two side down-looking cameras were used to capture road surface image to extract lane markings. A synchronization device were used to generate image capturing signal at the fixed distance spacing huck as every 10m. The front view images could be used to calculate and measure highway geometry such as shoulder width because every image is saved with it's locational information. And also the side down looking images could be used to extract median lane mark which representing road alignement efficiently.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.245-251
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• 2020

From the perspectives of grammaticalization and corpus, the purpose of this study is to examine the motivation of the emergence of the split infinitives in American English and to discuss the justification of the split infinitives based on the corpus empirical data such as COHA and COCA. The formerly ungrammatical split infinitives in the form of [to + adverb + verb] are now definitely grammatical forms in Present Day English (PDE). The corpus-based data confirms the legitimacy of the split infinitives with the empirical reasons like clarifying sentences (i.e., disambiguation) or strongly focused readings. In addition, the split infinitives are natural consequences caused by the grammaticalization of an infinitival particle to and most crucially by the loss of verb movement. When verb movement to T position does not occur in infinitival clauses, the word order results in [to + AdvP + V], thus forming the split infinitives. The split infinitives are no longer a matter of discussion and will continue to increase in both formal and informal contexts as being definitely grammatical forms.

• Journal of Internet Computing and Services
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• v.15 no.1
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• pp.179-191
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• 2014

In this paper, a frame transmission method to make IEEE 802.15.4 nodes run at a new channel and its characteristics are studied when they experience difficulties in transmission of frames due to WiFi traffic. The researches on evaluating the interference from WiFi traffic, searching for a new channel with little interference or not, and changing the operating channel are analyzed. In an wireless channel overlapped with IEEE 802.11 network, the transmission delay of IEEE 802.15.4 frames, the collision of frames in sending IEEE 802.15.4 frames without applying CSMA-CA algorithm, and the operation of IEEE 802.11 nodes are explained. A transmission method of frames including frame-formated code blocks in order to use the rest part of collided IEEE 802.15.4 frame is proposed. In the experiments of the proposed method, it is observed that frame-formated code blocks are synchronized and received by receivers in case of collision, and then the collided positions in IEEE 802.15.4 frame and the characteristics of frame reception rate are analyzed. The experimental results show that the performance of the proposed method is improved in comparison to an existing method when we measure the time taken to send a channel change command and get the response in order to avoid the interference from WiFi traffic.