• 한국치위생학회지
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• 제24권2호
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• pp.149-162
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• 2024

Objectives: This study aimed to identify the level of digital oral health literacy among Korean adults in Gangwon-do. Methods: A survey was conducted through face-to-face interviews with adults aged 30-89 residing in Gangwon-do, South Korea. The independent variables were socio-demographic characteristics, including gender, age, education level, income, and occupation. The dependent variable was digital oral health literacy. The statistical analysis included Independent t-test, one-way ANOVA, Pearson correlation analysis, and multiple linear regression analysis, all performed using the SPSS 27.0 software program. Results: The elderly and those with poor socioeconomic status (p<0.001) had lower average scores due to poor digital oral health literacy. The ease of searching for oral health information and the utilization of digital devices to search for information on oral health displayed a significant relationship (r=0.730, p<0.001). To develop the use of digital devices, simplifying the search for oral information (p<0.001) is essential. Conclusions: All socio-demographic characteristics, except gender, displayed a correlation with the level of digital oral health literacy. Both environmental and individual aspects of the respondents' living conditions must be considered to improve digital oral health literacy.

• The Journal of Advanced Prosthodontics
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• 제9권6호
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• pp.432-438
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• 2017

PURPOSE. The purpose of this study was to evaluate the in vitro validity of quantitative light-induced fluorescence-digital (QLF-D) and laser fluorescence (DIAGNOdent) for assessing proximal caries in extracted premolars, using digital radiography as reference method. MATERIALS AND METHODS. A total of 102 extracted premolars with similar lengths and shapes were used. A single operator conducted all the examinations using three different detection methods (bitewing radiography, QLF-D, and DIAGNOdent). The bitewing x-ray scale, QLF-D fluorescence loss (${\Delta}F$), and DIAGNOdent peak readings were compared and statistically analyzed. RESULTS. Each method showed an excellent reliability. The correlation coefficient between bitewing radiography and QLF-D, DIAGNOdent were -0.644 and 0.448, respectively, while the value between QLF-D and DIAGNOdent was -0.382. The kappa statistics for bitewing radiography and QLF-D had a higher diagnosis consensus than those for bitewing radiography and DIAGNOdent. The QLF-D was moderately to highly accurate (AUC = 0.753 - 0.908), while DIAGNOdent was moderately to less accurate (AUC = 0.622 - 0.784). All detection methods showed statistically significant correlation and high correlation between the bitewing radiography and QLF-D. CONCLUSION. QLF-D was found to be a valid and reliable alternative diagnostic method to digital bitewing radiography for in vitro detection of proximal caries.

• ETRI Journal
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• 제33권4호
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• pp.537-546
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• 2011

This paper introduces an automated method for building height recovery through the integration of high-resolution satellite images and digital vector maps. A cross-correlation matching method along the vertical line locus on the Ikonos images was deployed to recover building heights. The rational function models composed of rational polynomial coefficients were utilized to create a stereopair of the epipolar resampled Ikonos images. Building footprints from the digital maps were used for locating the vertical guideline along the building edges. The digital terrain model (DTM) was generated from the contour layer in the digital maps. The terrain height derived from the DTM at each foot of the buildings was used as the starting location for image matching. At a preset incremental value of height along the vertical guidelines derived from vertical line loci, an evaluation process that is based on the cross-correlation matching of the images was carried out to test if the top of the building has reached where maximum correlation occurs. The accuracy of the reconstructed buildings was evaluated by the comparison with manually digitized 3D building data derived from aerial photographs.

• 한국분무공학회지
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• 제12권4호
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• pp.191-197
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• 2007

This study presents in-line digital particle holography and its application to spray droplets to measure the characteristics of spray droplets. Several important parameters at the time of hologram recording such as the object distance and the region of laser beam used were verified. The correlation coefficient method with important parameters such as the reconstruction interval and the correlation interval was used for determination of the focal planes of particles. The optimal values of all these parameters are obtained by either numerical simulation of holograms or experiments. Using these optimal parameters, double pulse digital spray holograms in a short time interval were recorded with the synchronization system for the time control. The spatial positions of droplets that are used for the evaluation of the three dimensional droplet velocities can be easily located, which proves the feasibility of the digital holographic technology for measurements of several important features of spray droplets.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.241-245
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• 2007

The residual stress in axial stress in the axial direction of the steel filaments has been measured by using a method based on the combination of the focused ion beam (FIB) and high resolution strain mapping program (VIC-2D). That is, the residual stress was calculated from the measured displacement field before and after the introduction of a slot along the steel filaments. The displacement was obtained by the digital correlation analysis of high-resolution scanning electron micrographs, while the slot was introduced by FIB milling with low energy beam. The present measurement revealed that the residual stress within 8% of the magnitude was persistent in the steel filaments fabricated.

• Advances in aircraft and spacecraft science
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• 제6권1호
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• pp.69-86
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• 2019

This paper discusses the use of the Digital Image Correlation (DIC) technique for the displacement and strain measurements of a wet lay-up composite wing. As opposed to classical strain gages, DIC allows to conduct full field strain analysis of simple to complex structural parts. In this work, wing-up bending tests and measurements of the composite wing of the Dardo Aspect by CFM Air are carried out through an ad-hoc test rig and the Q-400 DIC system by Dantec Dynamics. Also, the results are used to validate a finite element model of the structure under investigation.

• Smart Structures and Systems
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• 제24권5호
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• pp.597-606
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• 2019

Damage detection based on dynamic characteristics of a structure is one of important roles in structural damage identification. It is difficult to detect local structural damage using traditional dynamic experimental methods due to a limited number of sensors used in an experiment. In this work, a non-contact test stand of fan blades is established, and a full-field noncontact test method, combined with three-dimensional digital image correlation, Bayesian operational modal analysis, and damage indices, is used to detect local damage of a fan blade under ambient excitation without use of baseline information before structural damage. The methodology is applied to detect invisible local damage on the fan blade. Such a method has a seemingly high potential as an alternative to detect local damage of blades with complex high-precision surfaces under extreme working conditions because it is a noncontact test method and can be used under ambient excitation without human participation.

• International Journal of Internet, Broadcasting and Communication
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• 제9권3호
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• pp.27-34
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• 2017

According to the material about the analysis of digital consumers' lifestyle in Korea published at the end of 2016, 100% had experienced a smartphone before, and 91% had joined in digital communications. Among digital contents, 85.5% had experienced music, and 78.6% had used TV contents before. Also, SNS utility rate equaled 83.3%, and the Facebook utility rate of those in the 10's and 20's exceeded 80%. It means that it is necessary to conduct research on SNS utility in broadcasts. Based on the results of operating KBS Facebook accounts, this paper aims to compare the reaches of entertainment, drama, and culture genres and analyze correlation between the reaches and 'like' friends on Facebook and also correlation between the reaches and ratings.To address the goal, among the Facebook mentions operated within a year, 2016, this researcher analyzed 2,526 mentions to publicize entertainment, drama, and culture genres and the results of 834 million reaches and also used the data of original broadcasts' ratings. To analyze the data, this study employed SPSS Ver. 18.0 to perform the independent sample t-test and Pearson's correlation analysis. The conference interval is set as 95%, and p<0.05 is regarded to be statistically significant. According to the results, more reaches are found in entertainment, drama, and culture genres in order, and it is found to have strongly positive correlation with the frequency of 'like's. The reaches and ratings have no correlation, and there is no statistical significance found in it. It is expected that the results of this study can be applied to publicize programs efficiently for broadcasting.

• 디지털융복합연구
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• 제12권2호
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• pp.45-59
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• 2014

디지털경제를 맞이하여 지난 1980년대 중반 이후 부동산이 가장 선호하는 투자자산으로 부각되면서 많은 관심을 받아오고 있다. 부동산 중에서 주택가격의 상승과 하락은 가계 및 국가경제에 많은 비중을 차지하고 있다. 본 연구에서는 서울지역 아파트가격과 KOSPI, 건설주, 증권주, 금리, 환율 지표를 이용하여 지난 1987년 1월부터 2013년 8월까지 총 320개월 동안 월별 동향을 살펴보면서 서울지역 아파트가격과 각 지표와의 상관관계를 살펴보았다. 또한 서울지역 아파트가격의 상승과 하락에 어느 지표가 얼마나 영향을 주는지도 분석하였다. 상관관계 분석결과 서울지역 아파트가격과 KOSPI의 상관계수는 0.8566로 높은 양(+)의 값을 보여주었으나 반대로 금리는 -0.7846으로 강한 음(-)의 상관관계를 보여주었다. 주식시장의 상승은 서울지역 아파트가격 상승에 많은 영향을 주고 있으며 금리 하락은 서울지역 아파트가격의 가격상승으로 나타난다고 해석된다. 연구결과 서울지역 아파트가격은 KOSPI를 비롯하여 각 지표들과 통계적으로 유의한 관계를 유지하며 변동하고 있는 것으로 나타났다.

• 치과방사선
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• 제29권2호
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• pp.417-422
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• 1999

Purpose : The aim of this study was to assess the validity of standard deviation of gray scale histogram in digital subtraction radiography as a test parameter for superimposition error. Materials and Methods : Twenty periapical radiographs were used as baseline images and they were copied to exclude the influence of exposure geomety and contrast differences. These subsequent images were linearly displaced by 0.1-0.5 mm in the x-. y- and xy-directions, rotated by 0.5-3° and distorted by angular contraction of 1-5° in x- and y-axis before subtraction. The standard deviations of gray levels in the subtraction images were obtained and paired t-tests were performed. Pearson correlation coefficients(r) were calculated between the standard deviations and the superimposition errors. Results : Linear displacement showed high correlation coefficients of 0.997, 0.997 and 0.995 in x-. y- and xy-axis respectively. Statistically significant different standard deviation existed among all linearly displaced groups(p<0.05). Distortion showed relatively low correlation coefficients of 0.982 and 0.959 in x- and y-axis. The standard deviations between the two distortion groups were statistically significant different(p<0.05). Conclusion : Standard deviation of gray level distribution in digital subtraction images is satisfactory but not perfect similarity measure to assess the superimposition errors.