• 한국정보통신학회논문지
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• 제16권10호
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• pp.2267-2272
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• 2012

본 연구에서는 이중게이트 MOSFET에서 스켈링 이론에 대한 문턱전압이하 스윙을 분석하였다. 포아송방정식의 해석학적 전위분포를 구하기 위하여 가우스 전하분포를 이용하였다. 문턱전압이하 스윙의 저하와 같은 단채널 효과를 분석하기 위하여 스켈링이론이 사용되었으며 이중게이트 MOSFET의 특성상 두 개의 게이트 효과를 포함하기 위하여 일반적인 스켈링 이론을 수정하였다. 게이트길이에 대한 스켈링인자가 일반적인 스켈링인자의 1/2일 때 문턱전압이하 스윙의 저하현상이 매우 빠르게 감소하였으며 가우스함수의 이온주입범위 및 분포편차도 문턱전압이하 스윙에 영향을 미치는 것을 알았다.

• 한국도로학회논문집
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• 제16권6호
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• pp.27-37
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• 2014

PURPOSES : The purpose of this study is to verify the causes of surface scaling at L-shoulder concrete structure. METHODS : From the literature reviews, mechanisms of frost damage were studied and material properties including strength, air void, spacing factor and scaling resistance of L-shoulder concrete structure were analyzed using core specimens taken by real fields. RESULTS : The spacing factor of air void has relatively high correlation of surface conditions : lower spacing factor at good surfacing condition and vice versa. If the compressive strength is high, even thought spacing factor does not reach the threshold value of reasonable durability, the surface scaling resistance shows higher value. Based on these test results, the compressive strength also provide positive effect on the surface scaling resistance. CONCLUSIONS : The main causes of surface scaling of L-shoulder could be summarized as unsuitable aid void amount and poor quality of air void structure. Secondly, although the compressive strength is not the governing factor of durability, but it shows the positive effect on the surface scaling resistance.

• Earthquakes and Structures
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• 제5권2호
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• pp.129-142
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• 2013

Linear and nonlinear time history analyses have been becoming more common in seismic analysis and design of structures with advances in computer technology and earthquake engineering. One of the most important issues for such analyses is the selection of appropriate acceleration time histories and matching these histories to a code design acceleration spectrum. In literature, there are three sources of acceleration time histories: artificial records, synthetic records obtained from seismological models and accelerograms recorded in real earthquakes. Because of the increase of the number of strong ground motion database, using and scaling real earthquake records for seismic analysis has been becoming one of the most popular research issues in earthquake engineering. In general, two methods are used for scaling actual earthquake records: scaling in time domain and frequency domain. The objective of this study is twofold: the first is to discuss and summarize basic methodologies and criteria for selecting and scaling ground motion time histories. The second is to analyze scaling results of time domain method according to ASCE 7-05 and Eurocode 8 (1998-1:2004) criteria. Differences between time domain method and frequency domain method are mentioned briefly. The time domain scaling procedure is utilized to scale the available real records obtained from near fault motions and far fault motions to match the proposed elastic design acceleration spectrum given in the Eurocode 8. Why the time domain method is preferred in this study is stated. The best fitted ground motion time histories are selected and these histories are analyzed according to Eurocode 8 (1998-1:2004) and ASCE 7-05 criteria. Also, characteristics of both near fault ground motions and far fault ground motions are presented by the help of figures. Hence, we can compare the effects of near fault ground motions on structures with far fault ground motions' effects.

• 한국치위생학회지
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• 제18권1호
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• pp.77-92
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• 2018

Objectives: The purpose of this study was to review depression and anxiety associated with pain during scaling procedures, and to establish measures for reducing scaling pain encompassing not only physical factors but also psychological aspects of patients. This study also attempts to reduce anxiety through proper patient education prior to scaling procedures. Methods: In Seoul, and Gyeonggi area from July 26, 2017 to August 19, 2017, there were 327 copies of questionnaire data collected, excluding 23 questionnaires with insufficient information such as missing entries. The following inductions were made based on data collected. Results: There are positive correlations between pain and depression, dental anxiety, trait anxiety, and state anxiety. Especially, stronger correlation is present between pain and dental anxiety. Depression (${\beta}=0.439$, p<0.001) is the most influential factor associated with pain. Next is dental anxiety (${\beta}=0.292$, p<0.001). Higher the depression and dental anxiety tend to increase pain over scaling procedure. This model is with adjusted explanatory power of 28.2%. Conclusions: The result demonstrates that there is a correlation between scaling pain and depression, dental anxiety, trait anxiety, and state anxiety. Especially, depression and dental anxiety were prominent factors in affecting scaling pain. Therefore, considering aforementioned-findings, a dental hygienist's positive attitude may help in reducing the pain of the patient during scaling procedures, by affecting the psychological state of the patient and reduce the anxiety through proper education prior to scaling procedures.

• 한국치위생학회지
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• 제14권3호
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• pp.431-438
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• 2014

Objectives : The purpose of the study is to investigate the recognition between laypersons and dental hygienists on expansion of health insurance of scaling. Methods : A self-reported questionnaires was filled out by 100 laypersons and 100 dental hygienists from October 7, 2013. Data were analyzed by SPSS version 21.0 program. Results : All the dental hygienists recognized the introduction of the health insurance of scaling and 71.0% of the laypersons agreed. The introduction of health insurance of scaling was responsible for the interest toward scaling in 80 dental hygienists(80.0%) and 66 laypersons(66.0%). 94% of dental hygienists answered that health insurance of scaling would prevent periodontal diseases. The expansion of health insurance of scaling revealed many periodontal diseases and 52% of laypersons answered that prevention of periodontal diseases would deprive the dental hygienists of their jobs. Conclusions : The expansion of health insurance of scaling can prevent the periodontal diseases and enhance the oral health services. So the government must try to expand the health insurance of scaling.

• Journal of Astronomy and Space Sciences
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• 제28권3호
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• pp.183-192
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• 2011

The current study analyzes the effects of the scaling parameters of the batch unscented transformation on precision satellite orbit determination. Satellite laser ranging (SLR) data are used in the orbit determination algorithm, which consists of dynamics model, observation model and filtering algorithm composed of the batch unscented transformation. TOPEX/Poseidon SLR data are used by utilizing the normal point (NP) data observed from ground station. The filtering algorithm includes a repeated series of processes to determine the appropriate scaling parameters for the batch unscented transformation. To determine appropriate scaling parameters, general ranges of the scaling parameters of ${\alpha}$, ${\beta}$, k, $\lambda$ are established. Depending on the range settings, each parameter was assigned to the filtering algorithm at regular intervals. Appropriate scaling parameters are determined for observation data obtained from several observatories, by analyzing the relationship between tuning properties of the scaling parameters and estimated orbit precision. The orbit determination of satellite using the batch unscented transformation can achieve levels of accuracy within several tens of cm with the appropriate scaling parameters. The analyses in the present study give insights into the roles of scaling parameters in the batch unscented transformation method.

• 한국정보통신학회논문지
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• 제16권7호
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• pp.1463-1469
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• 2012

본 연구에서는 문턱전압이하 영역에서 이중게이트 MOSFET에서 스켈링 이론이 단채널효과에 미치는 영향을 관찰하였다. 기존 MOSFET의 경우 출력특성을 일정하게 유지하기 위하여 스켈링 이론을 적용하여 전류 및 스위칭 주파수를 해석하였다. 이중게이트 MOSFET에서 단채널효과에 대한 스켈링 이론의 적용 결과를 분석하기 위하여 문턱전압, 드레인유기장벽감소 및 문턱전압이하 스윙 등을 스켈링 인자에 따라 관찰하였다. 이를 위하여 이미 검증된 포아송방정식의 해석학적 전위분포를 이용하였다. 분석결과 단채널효과 중 문턱전압이 스켈링 인자에 가장 큰 영향을 받는다는 것을 관찰하였다. 특히 채널길이에 스켈링 이론을 적용할 때 가중치를 이용한 변형된 스켈링 이론을 적용함으로써 이중게이트 MOSFET에 가장 타당한 스켈링 이론에 대하여 설명하였다.

• 한국치위생학회지
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• 제16권5호
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• pp.661-667
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• 2016

Objectives: The objective of the study was to investigate oral health index between adequate and inadequate dental care following preventive scaling in regular dental check-up and management. Methods: The subjects in Busan were assigned to two groups including inadequate dental care (140 patients) and adequate dental care (88 patients) after preventive scaling from January 2014 to June 2015. The study instruments included oral health knowledge, awareness, practice, and community periodontal index of treatment needs (CPITN). Results: CPITN was significantly different between the two groups (p<0.05). Positive correlations were found in oral heath knowledge and awareness (r=0.462, p<0.05) before application of preventive scaling. There was a close correlation in oral health awareness and practice (r=0.205, p<0.05) before application of preventive scaling. After application of preventive scaling, oral health knowledge and awareness showed positive correlation (r=0.643, p<0.05). After application of preventive scaling, there was also a close correlation between oral health knowledge and practice (r=0.453, p<0.05). Oral health awareness and practice (r=0.512, p<0.05) showed positive correlation after the application of preventive scaling. However, oral health practice and CPITN (r=-0.189, p<0.05) showed a negative correlation. Conclusions: Practice made periodontal condition improve. To promote oral health practice in the group without adequate dental care, it is necessary to pay attention to adequate dental care and preventive scaling through education by dental hygienists.

• 한국정보통신학회논문지
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• 제16권5호
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• pp.982-988
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• 2012

본 연구에서는 이중게이트(Double Gate; DG) MOSFET에서 문턱전압과 스켈링 이론의 관계를 관찰하였다. 기존 MOSFET의 경우 채널크기에 스켈링 이론을 적용하여 전류 및 스위칭주파수를 해석하였다. 이에 본 연구에서는 이중게이트 MOSFET에서 문턱전압의 경우 스켈링 이론의 적용가능성을 관찰하기 위하여 문턱전압의 변화를 스켈링 인자에 따라 관찰하고 분석하였다. 이를 위하여 이미 검증된 포아송방정식의 해석학적 전위분포를 이용하였으며 이때 가우스함수의 전하분포를 사용하였다. 분석결과 문턱전압이 스켈링 인자에 따라 크게 변화하였으며 변화정도는 도핑농도의 스켈링에 따라 변화한다는 것을 관찰하였다. 특히 이중게이트의 특성상 채널두께 및 채널길이에 스켈링 이론을 적용할 때 가중치를 이용한 변형된 스켈링 이론을 적용함으로써 이중게이트 MOSFET에 가장 타당한 스켈링 이론에 대하여 설명할 것이다.

• 한국치위생학회지
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• 제19권5호
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• pp.765-776
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• 2019

Objectives: The purpose of this study was to compare the oral health statuses pre- and post-insurance using the $5^{th}$ and $6^{th}$ National Health and Nutrition Examination Survey data to confirm the effect of scaling insurance after a year. Methods: Data were analyzed using IBM SPSS ver. 21.0 (IBM Co., Armonk, NY, USA). The four years were integrated, and a composite sample analysis was performed. A total of 26,990 people were included in the study before applying for scaling insurance (14,343 persons) or after receiving scaling insurance (12,647 persons). A chi-squared test was performed to compare the demographic characteristics and oral health status of the subjects. The significance level of the statistical test was 0.05. Results: The proportion of patients without implants was high before the provision of scaling insurance once a year, however, the proportion of patients with one or more implants was high (p<0.05) after the provision of scaling insurance once a year. Hemorrhagic periodontal tissues and tartar formation in periodontal tissues were highly prevalent before the provision of scaling insurance once a year, however, healthy periodontal tissues and formation of periodontal pockets were highly prevalent (p<0.05) after the provision of scaling insurance once a year. The decay, missing, and filled teeth index scores were higher before the provision of scaling insurance once a year (p<0.05). Conclusions: The aforementioned results showed that scaling once a year helps prevent or treat periodontal disease. In addition, we confirmed the effect of prevention on periodontal disease and dental caries, therefore, we expect it to develop into a stable policy.