• Journal of Oral Medicine and Pain
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• 제19권2호
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• pp.153-168
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• 1994

The aim of the present study was to investigate a relation between occlusal wear area and occlusal contact patterns. For the purpose, occlusal wear area were measured in 58 dental students and in 129 patients with temporomandibular disorders(TMDs) from dental casts. Teeth used in this study were from canine to second molar on both sides in upper arch, totally ten. Occlusal wear area on casts was marked by pencil and photocopies, and then, the area was measured with planimeter. Occlusal relation was clinically examined with regard to Angle's classification, chewing side preference, lateral guidance pattern and bruxing and/or clenching habit. T-Scan, electronic occlusal contact analyzer, was used to record occlusal contact number, contact force, contact time and occlusal balance that is TLR(total left-right statistics) during tooth contact. All measurement were repeated 3 times and the average value was used for data processing. The obtained results were as follows : 1. Mean value of occlusal wear area did not differ significantly between dental students and patients. 2. There ws not significant difference in wear area between chewing side and non-chewing side in both groups. 3. Occlusal wear area was significantly increased with age in both groups. 4. Three subgroups divided by Angle's classification did not show any difference in occlusal wear area among them, but three subgroups divided by lateral guidance pattern showed slightly significant difference between canine guide subgroup and group function subgroup in patients. Occlusal wear ares\a in group function subgroup wear larger than canine guide subgroup. 5. Mean value of wear area in patients with bruxing and/or clenching habit did not differ from those in patients without such habit. 6. Correlationship among items related to occlusal contact pattern were highly consistent and significant in dental students and only one item significantly correlated with occlusal wear area was tooth contact time.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.242-245
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• 2003

A garter spring, which is a long, special, close-coiled extension spring with its ends joined to form a ring, is used in tulip contactor between vacuum circuit breaker and bus bar in switchgear. To carry short-time current and resist welding at the contact surface in the tulip contactor, the garter spring must transmits an uniform contact force to the contact surface through the contact chips arranged in the circumference of bus bar. In this paper, the system for measurement of the contact force by the garter spring is developed. Using the developed measurement system, the design of the connection structure including the garter spring is reviewed to obtain the uniform contact forces in all of contact chips.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 춘계종합학술대회
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• pp.279-282
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• 2002

In this paper, we discuss influence of process condition on contact resistance in WSix deposition process. In the WSix deposition process, we confirmed that word line to bit line contact resistance(WBCR) due to temperature of word line WSix deposition among various process condition split experiment. RTP treatment, d-poly ion implantation dose and thickness was estimated a little bit influence on contact resistance. Also, life time of shower head in the process chamber for WSix deposition related to contact resistance. The results obtained in this study are applicable to process control and electrical characteristics for high reliability and high density DRAM's.

• 상하수도학회지
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• 제13권2호
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• pp.82-88
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• 1999

This study was to evaluate disinfection efficiency of chlorine and chloramine as secondary disinfectants in the distribution systems. Indicator organism, HPC in the suspended and attached were measured for copper, galvanized steel, PVC, and carbon steel pipes. For suspended microorganism, the PVC pipe was markedly dense among the assessed pipe materials. The attached microorganism was markedly equivalent roughness of pipe materials. In copper and galvanized pipes, chloramine was more effective that free chlorine to disinfect suspended microorganism in the contact time of 2 hours. The contact time for the 99% inactivation of suspended microorganism by chloramine was longer than that of free chlorine. Regardless of pipe materials, chloramine was effective on both disinfection efficiency and 99% inactivation time for attached microorganism. In conclusion, chloramine which is good disinfectant for long contact time was recommended as secondary disinfectant in distribution system.

• Journal of Welding and Joining
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• 제16권2호
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• pp.122-128
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• 1998

This investigation was performed to collect fundamental informations concerning the behavior of glass solders on ceramic joining process. The wettability of glasses on two types of alumina was evaluated by sessile drop method. SiO$_2$-CaO-Al$_2$O$_3$system glasses were selected as solder glasses, and alumina that have different purities were used for substrate materials. It is indicated that contact angles of glasses on 99% purity of alumina substrate do not change as increasing time at elevated temperature, however the contact angles on the 92% purity of alumina substrate exhibit the strong time dependency. The time-dependent property on 92% alumina was due to the interlayer reactions occurred between the glass solder and impurities on the substrate.

• 제어로봇시스템학회논문지
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• 제4권3호
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• pp.334-341
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• 1998

This paper proposes an algorithm to obtain the time-to-contact between an observer and a target and surface orientation of the target. These two physical elements are computed from the image deformation of a known shape, which is extracted by supervised classification of detected line segments based on MAP and Mahalanobis distance. The proposed algorithm was applied to the natural outdoor traffic scene and would contribute to the development for a collision avoidance system.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.501-505
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• 1996

In CMM system, a contact probe is not applicable to very small, or flexible elements. There is need to develop non-contact probes of CCD camera. But non-contact probes have some technical problems, including distortion, user interface and time delay. This development gives the foundation of the non-contact probe system and some useful solutions for the problems. The results can be useful for industry application.

• 한국학교보건학회지
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• 제20권2호
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• pp.59-68
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• 2007

Purpose: The purpose of this study was to investigate the difference of sexual behaviors of college students according to internet pornography contact. Methods: Subjects consisted of 472 students of K college located in chungcheongbuk-do. The data were collected through a self-administered questionnaire from May, 21 to May, 31, 2007. Results: Eighty-seven percent (87.3%) of respondents contacted internet pornography. As for the first time they contacted it, forty-eight percent(48.3%) contacted it when they were middle school students. Forty-three percent(43.6%) contacted it one time per several months and twenty-one percent(21.2%) contacted it within 10 minutes. Sexual behaviors(hand grasping, hugging, kiss, masterbation, coitus, pregnancy, love expression in public place) showed significant differences according to Internet pornography contact experience, period, frequency, and time. Conclusion: College administration should investigate sexual behavior patterns according intemet pornography contact and provide all college students regular sexual health promotion program.

• Journal of Oral Medicine and Pain
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• 제31권4호
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• pp.365-373
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• 2006

이 연구는 경찰사회에서의 측두장애환자의 교합상태를 평가하여 습관적인 최대교합시에 교합접촉 시기와 접촉수, 접촉힘을 분석하여 과도한 개구나 이악물기등의 악습관 교정을 제시 하는데 있다. 경찰사회에서는 일반 사회에는 다른 양상의 최대 개구, 습관적인 긴밀한 최대 교합상태 등으로 인하여 측두하악장애에 영향을 미칠 수 있다. 반복적인 훈련이나 일상생활에서의 변화는 그동안 유지되어 오던 저작근을 비롯한 악구강계 평형 상태에 변화를 초래하여 측두하악관절과 그에 따른 구조물에 동통을 유발 내지는 악화 시킬 수 있다. 본 연구는 측두하악장애에 영향을 미칠 수 있는 교합상태를 조사하기 위하여 T-scan II system(Tekscan Co., USA)을 이용하였으며, 최대 교합력을 발휘하기 위하여 약 20 mm 정도의 개구 상태에서 최대교합시까지 물었다. 경찰종사자의 측두하악장애환자는 일반 측두장애환자보다 최초 접촉부터 최대 접촉까지 걸리는 시간은 오래 걸리며, 최종 접촉까지의 시간은 보다 짧았으며, 최종 교합접촉력은 더 강하여, 더 짧은 시간에 강한 힘을 유지한 채 폐구가 이루어져 측두하악관절에 더 많은 잔존한 부하를 전달하였다. 이환 측과 교합접촉 시간, 교합 접촉 힘등의 교합양상과는 관계가 미약하였으며, 최대 접촉력이 가해진 시기에서 우측이 이환 측이면 우측 악궁에, 좌측이 이환측일 경우 좌측 악궁에 집중되는 좌, 우 악궁간 불균형을 보였다. 이상의 결과에서 측두하악장애를 가진 경찰 종사자들의 하악 운동에 보다 부드러운 움직임과 습관적인 최대 교합상태에서의 보다 적은 힘을 유지해야 할 것으로 생각되어진다.

• Journal of Information Processing Systems
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• 제18권3호
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• pp.359-373
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• 2022

The new crown pneumonia (COVID-19) has become a global epidemic. The disease has spread to most countries and poses a challenge to the healthcare system. Contact tracing technology is an effective way for public health to deal with diseases. Many experts have studied traditional contact tracing and developed digital contact tracking. In order to better understand the field of contact tracking, it is necessary to analyze the development of contact tracking in the field of computer science by bibliometrics. The purpose of this research is to use literature statistics and topic analysis to characterize the research literature of contact tracking in the field of computer science, to gain an in-depth understanding of the literature development status of contact tracking and the trend of hot topics over the past decade. In order to achieve the aforementioned goals, we conducted a bibliometric study in this paper. The study uses data collected from the Scopus database. Which contains more than 10,000 articles, including more than 2,000 in the field of computer science. For popular trends, we use VOSviewer for visual analysis. The number of contact tracking documents published annually in the computer field is increasing. At present, there are 200 to 300 papers published in the field of computer science each year, and the number of uncited papers is relatively small. Through the visual analysis of the paper, we found that the hot topic of contact tracking has changed from the past "mathematical model," "biological model," and "algorithm" to the current "digital contact tracking," "privacy," and "mobile application" and other topics. Contact tracking is currently a hot research topic. By selecting the most cited papers, we can display high-quality literature in contact tracking and characterize the development trend of the entire field through topic analysis. This is useful for students and researchers new to field of contact tracking ai well as for presenting our results to other subjects. Especially when comprehensive research cannot be conducted due to time constraints or lack of precise research questions, our research analysis can provide value for it.