• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.48-53
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• 2017

Objectives: The aim of this study was to investigate the ability of the fluorescence-aided caries excavation (FACE) device to detect residual caries by comparing conventional methods in vivo. Materials and Methods: A total of 301 females and 202 males with carious teeth participated in this study. The cavity preparations were done by grade 4 (Group 1, 154 teeth), grade 5 (Group 2, 176 teeth), and postgraduate (Group 3, 173 teeth) students. After caries excavation using a handpiece and hand instruments, the presence of residual caries was evaluated by 2 investigators who were previously calibrated for visual-tactile assessment with and without magnifying glasses and trained in the use of a FACE device. The tooth number, cavity type, and presence or absence of residual caries were recorded. The data were analyzed using the Chi-square test, the Fisher's Exact test, or the McNemar test as appropriate. Kappa statistics was used for calibration. In all tests, the level of significance was set at p = 0.05. Results: Almost half of the cavities prepared were Class II (Class I, 20.9%; Class II, 48.9%; Class III, 20.1%; Class IV, 3.4%; Class V, 6.8%). Higher numbers of cavities left with caries were observed in Groups 1 and 2 than in Group 3 for all examination methods. Significant differences were found between visual inspection with or without magnifying glasses and inspection with a FACE device for all groups (p < 0.001). More residual caries were detected through inspection with a FACE device (46.5%) than through either visual inspection (31.8%) or inspection with a magnifying glass (37.6%). Conclusions: Within the limitations of this study, the FACE device may be an effective method for the detection of residual caries.

• Journal of the Ergonomics Society of Korea
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• v.23 no.3
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• pp.39-52
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• 2004

Icons are the main element of the graphic user interface (GUI). They can help users perform effectively on the computer, especially when the icons reflect user`s mental model. However, few studies in Korea represented Korean users` mental models in icon design. The purpose of this study, therefore, was to ascertain whether existing icons agreement with Korean twentieth mental model, and to deduce properties of Korean twentieth mental model. To do that, 10 icons from two commercially available toolbar-icons of word processing programs were compared with the newly developed icons, which were developed to represent Korean user`s mental modelthrough interviews, surveys, and mental model sketches. The results show that five new metaphors were found: a dog-eared part on the bottom right corner new for new document, a magnifying glass for search, a red pencil for spell-check, `＋` and `` signs in the magnifying glass for zoom, and a yellow post-it for paste. These new icons were preferred to the existing. Korean twentieth users preferred rather complex and dynamic icons than simple and static ones even though icon development guideline said simple icons are better.

• Applied Microscopy
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• v.33 no.2
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• pp.93-104
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• 2003

Since the Ptolemaeos' discovery that glass has magnifying power, human desire to see the unseen with naked eyes has lead to the inventions of a series of microscopes. Since the Janssen's first compound microscope in 1595, through the Abbe's non-aberration microscopy, various microscopes using different principles are now being used in various biomedical researches. The discovery of electron by Thompson in 1897 has lead to the first invention of microscope using electron as an illumination source, the electron microscope, in 1931. Now we can see the objects as close as 0.05 nm using 1 MV FE-TEM constructed in 2000. In this review, the authors reviewed the predecessors efforts to develop better microscopes.

• Journal of ILASS-Korea
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• v.17 no.1
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• pp.9-13
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• 2012

This study investigates experimentally evaporation characteristics of nanofluid droplets containing 50 nm alumina($Al_2O_3$) particles and the wettability changes on a hydrophilic glass surfaces. From the captured digital images by using a CMOS camera and a magnifying lens, we examined the effect of particle concentration on droplet evaporation rate which can be indirectly deduced from the measured droplet volumes varying with time. In particular, with the use of a digital image analysis technique, the present study measured droplet perimeters and the contact angles to study the wetting dynamics during evaporating process. In addition, we compared the measured total evaporation time with theoretically estimated values. It was found that as the volume fractions of nanofluid increased, the total evaporation time and the initial contact angles decreased, while the droplet perimeters increased.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.721-731
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• 1995

The purpose of this study was to evaluate the adaptability to tooth structure of light-cured glass ionomer cements. In this, study, class V cavities were prepared on the buccal surfaces of thirty extracted human premolar teeth, and they were randomly assigned into 3 groups with 10 teeth. The cavities of each groups were filled with the Fuji II LC(GC International Corp., Japan), Vitremer(3M Dental Products Division, U.S.A) and VariGlass VLC(Caulk/Dentsply Inc., U.S.A.). The specimens were immersed in 1% methylene blue solution and stored in 100% realtive humidity at $37^{\circ}C$ for 5 days. And then, the specimens sectioned buccolingually. Degree of eke penetration at tooth--restoration interfaces were examined by magnifying glass at occlusal and gingival margin. The results were as follows : 1. On the occlusal margin, among the experimental groups, the group 2 showed the lowest microleakage($1.40{\pm}1.17$) and the group 1 showed the highest microleakage($3.10{\pm}0.99$). There was significant difference between group 1 and group 2(P<0.01). 2. On the gingival margin, among the experimental groups, the group 2 showed the lowest microleakage($2.50{\pm}1.08$) and the group 1 showed the highest microleakage($3.50{\pm}0.84$). But there was not significant. difference among the experimental groups(P>0.05). 3. The degree of microleakage at occlusal margin was less than gingival margin in all experimental groups.

• Restorative Dentistry and Endodontics
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• v.6 no.1
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• pp.105-107
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• 1980

A total of 125 extracted maxillary first molars were used to study the configuration of the floor of the pulp chamber. The specimens were ground and the pulp chamber was examined with a magnifying glass and explored with sharp explorer. The study showed the shape of the pulp chamber, number of root canals, and type of canal orifice. The results were as follows; 1. In so far as observing the shape of the pulp chamber of the teeth, 50.4% of the teeth were trapezoid, 20.8% were inverted trapezoid, 18.4% were rectangle and 10.4% were triangle shape. 2. 71.2% of the specimens have 3 root canal orifices, and 28.8% have 4 root canal orifices. 3. 71.2% of the specimens have 1 mesiobuccal canal orifice, 23.2% have 2 mesio-buccal canal orifices joined by a groove, and 5.6% have 2 mesio-buccal canal orifices seperated each other.

• English & American cultural studies
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• v.9 no.1
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• pp.323-348
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• 2009

Kazuo Ishiguro's fifth novel When We Were Orphans (2000) tells the story of Christopher Banks, a private detective, who embarks on the ultimate case of his career, the puzzle of his own life. The novel consists of two overall parts, one taking place in London, the other in Shanghai-a division which reveals one of the novel's major themes, the relation between home and abroad. Set in the 1930s, Ishiguro's novel on the one hand contains all the classic ingredients of the so called golden age detective genre-an archetypal English private detective, equipped with fierce deductive skills and a magnifying glass, as well as suspects, criminals, and victims-and yet on the other hand it also deviates in significant ways. In this article, I will attempt to make some links between When We Were Orphans and the genre paradigm of the golden age detective story, arguing that Ishiguro's novel offers an exploration of the genre's ideological connections to a larger historical discourse of imperial nostalgia and decline.

• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.151-158
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• 1988

The purpose of this study was to evaluate the effect of canal filling methods and post-space preparation time on the apical seal of endodontically treated teeth. Seventy-six single-rooted human teeth were divided into 6 groups and each tooth was obturated and prepared post-space according to the purpose of this study. After all specimens were immersed in Indian ink, decalcified and cleared, the degree of dye penetration into the root canals observed by magnifying glass (X20) and measured by caliper. The results were as follows: 1. In the thermatic condensation, no significant difference in ink penetration occured when the post-spaces were created immediately after obturation or when they were made a week later. 2. In the lateral condensation, no significant difference in ink penetration existed between teeth whose post-space were prepared immediately or delayed. 3. In comparison of experimental groups and control groups, no significant difference showed when the groups were obturated with McSpadden compactor but when the teeth were laterally condensed, the experimental groups showed less ink penetration than controls. 4. Thermatic condensed teeth with McSpadden compactor were less ink penetration thn laterally condensed teeth.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.2
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• pp.371-378
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• 2000

In this study, we proposed pathological pattern detection system for X-ray chest image using artificial neural network. In a physical examination, radiologists have checked on the chest image projected the view box by a magnifying glass and found out what the disease is. Here, the detection of X-ray fluoroscopy is tedious and time-consuming for human doing. Lowering of efficiency for chest diagnosis is caused by lots mistakes of radiologist because of detecting the micro pathology from the film of small size. So, we proposed the method for disease detection using artificial neural network and digital image processing on a X-ray chest image. This method composes the function of image sampling, median filter, image equalizer used neural network and pattern recognition used neural network. We confirm this method has improved the problem of a conventional method.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.2
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• pp.89-95
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• 2010

High contrast and high resolution are the most important factors for examining mammography images. Despite of the inconveniences of screen-film, most clinics still prefer them to computed radiography(CR) and direct radiography(DR). The reading of screen-film mammography images is influenced by the brightness from the X-ray illuminator, the exam room and incoming light from outside sources. Therefore, a comparative analysis on the results of mammo phantom images would be variated by the changes in the reading environment. There was no influence on reading results from the examiners close distance eyesight(p > 0.05); however, reading of micro lesions improved with greater darkness in the X-ray film reading room and the brightness of the X-ray illuminator(p < 0.05). Also, observation of fiber and mass images were maximized at a distance of 50 cm from the reader. Now, it is possible to observe these small classification groups using a magnifying glass without being physically close to the image. For the image of mammography, obtaining high quality images is important but in order to get an accurate clinical lesions of the reading also needs to be considered the optimal environmental factors.