• Restorative Dentistry and Endodontics
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• v.36 no.4
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• pp.290-299
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• 2011

Objectives: The usage of fluoride varnish for a moderate to low caries-risk group has not been well validated. This study aimed to evaluate the preventive and therapeutic efficacies of fluoride varnish on the initiated root caries. Materials and Methods: Ten premolars were sectioned into quarters, further divided into two windows, one of which was painted with Fluor Protector (1,000 ppm fluoride, Ivoclar Vivadent). An initial lesion with a well-preserved surface layer was produced by pH cycling. Scanned line analysis using energy dispersive spectrometry determined the weight percentages of Ca and P in the demineralized layer. Scanning Electron microscopy and confocal laser scanning microscopy (CLSM) evaluated the varnish-applied root surfaces. Results: The mean lesion depth (SD) was 12.3 (2.6) ${\mu}m$ (single cycling) and 19.6 (3.8) ${\mu}m$ (double cycling). Double cycling extended the lesion depth, but induced no more mineral loss than single cycling (p < 0.05). The mean weight percentages of Ca and P between groups with and without varnish were not significantly different (p < 0.05). A CLSM showed varnish remained within 15 ${\mu}m$ of the surface layer. Conclusions: When a mild acid challenge initiated root tissue demineralization, the application of low-concentration fluoride varnish did not influence the lesion depth or the mineral composition of the subsurface lesion.

• Cartoon and Animation Studies
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• s.36
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• pp.669-702
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• 2014

Today, in Korean modern fine arts, 'cartoon images' are utilized for their roles of the 'personas' of the artists, and as the 'texts' for the artistic discourses, while they play a role as a bridgehead between the public and art. In this study, we made a study, focusing on 'Atomouse' of Lee Dong-gi, in order to examine how the borrowing of the 'cartoon images' was made in the Korean modern fine arts, and what its period context is. 'Atomouse' of Lee Dong-gi is the first cartoon character that appeared in Korean modern fine arts, and it has acquired a symbolism of a subculture being acknowledged as art. In this study, we tried to find out what period contexts the changes of 'Atomouse' have, focusing on the private exhibitions of Lee Dong-gi, such as 'Smoking' Exhibition (2006), 'Bubble' Exhibition (2008), 'Double Vision' Exhibition (2008), 'The Garden of Uncertainty' Exhibition (2012) and 'Do Not Look Back with Angry Face' Exhibition (2013). Atomouse was born in the era of 'lack of pop' a change was attempted of it in the era of 'excess of pop' and its proceeding ended along with the 'settlement of the neo-pop'. From Atomouse started from the unconsciousness of the artist, we can find the 'identity' of the Republic of Korea, which was being influenced by the 'American and Japanese' culture, as well as the symbolism of a subculture being acknowledged as art, while it emerged as an icon to represent the Korean pop art of the time. Then, as the agony and self-examination of the artist was contained in it, its use was changed into the role as a persona and it was utilized as a tool to connect the and figurative worlds. In the end, the artist put an end to the proceeding of the 'Atomouse' at the boundaries of a persona and an alter ego, removing the creation with his own hands. In the process in which Lee Dong-gi created and changed 'Atomouse', the start-up and growth of the pop art are included in the history of the Korean modern fine arts, apart from a study of an artist. 'Atomouse' was not only painted on the walls of the subway stations in the form of public art, but it tried to closely communicate with the public through the collaboration with diverse media. It made the best use of the 'marketability' which a 'cartoon character' had at first, so that pure art was made a step closer to the public. So 'Atomouse' of Lee Dong-gi not only raised a subculture into the realm of high art, but lowered the door sill to high art. Through the study we could confirm what position 'Atomouse' of Lee Dong-gi, which started absurdly between parody and Hommage, takes in Korean modern art of today.

• Journal of The Korean Ophthalmological Society
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• v.59 no.12
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• pp.1114-1121
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• 2018

Purpose: We report the clinical outcomes of patients undergoing additional widening of the limbal incision to prevent disease recurrence after conjunctivo-limbal autograft combined with pterygial excision. Methods: We retrospectively compared 95 eyes with primary and 12 eyes with recurrent pterygia randomized to treatment via two surgical methods: conjunctivo-limbal autograft alone and combined with widening of the limbal incision to allow for pterygial removal. We widened the limbal incisions by 1 mm on both the superior and inferior limbal margins and removed the pterygia. The outcomes were compared between 39 eyes undergoing conjunctivo-limbal autograft alone and 68 eyes undergoing conjunctivo-limbal autograft with widening of the limbal incision. Results: The mean overall postoperative follow-up period was $29.6{\pm}10.5months$ and conjunctivo-limbal autograft alone group was $27.4{\pm}11.5months$, combined with widening of the limbal incision group was $30.7{\pm}9.7months$. Six pterygia (15.4%; four primary and two recurrent) developed in those undergoing conjunctivo-limbal autograft alone and two (2.9%; one primary and one recurrent) in those undergoing additional widening of the limbal incision; the recurrence rate differed significantly between the two groups (p < 0.05). In the group treated with conjunctivo-limbal autograft alone, the mean time to development of a new primary pterygium was $6.3{\pm}3.4months$ and that to development of a recurrent pterygium $4.3{\pm}2.5months$; the respective values for the group undergoing additional widening of the limbal incision were $12.1{\pm}2.6$ and $8.4{\pm}4.6months$; the recurrence rates differed significantly (p < 0.05). Conclusions: Conjunctivo-limbal autograft with additional widening of the limbal incision used to treat both new primary and recurrent pterygia was more effective in terms of reducing pterygial recurrence than conjunctivo-limbal aAutograft alone.

• (The)Study of the Eastern Classic
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• no.37
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• pp.473-507
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• 2009

The purpose of this study is to understand Zhuxi's Taoxuezhengzhi(道學政治) by reorganizing both his political opinion in each different political situation and his consistent political consciousness appeared in his whole political career. He concluded that the politics was the real problematic in Southern Sung, which made its structure distorted. This distorted structure of politics had widely rooted in whole sphere of society. In order to cure this political problematic, Zhuxi had focused on huangdi(皇帝) and chaoting(朝廷). That is why people is the basis of State and the result of politics, while huangdi and chaoting is the basis of politics and the beginnig of politics. According to Zhuxi, forming their political power group of their own will by using huangdi's power, the political elites close to only to huangdi made the function of chaoting unstable, with the result that the political decay produced. In chaoting, it resulted in the weakness of huangdi's power, the collapse of official discipline(紀綱), and the absence of public opinion(公論) and public aggreement(公議). Beyond chaoting, it resulted in the absence of political trust and the degeneration of public morals(風俗). In the Southern Sung were not altered the political orientation and culture based on the political decay, but only political orientation and characteristics of political elite only altered. This proves Zhuxi's approach that all problems in Southern Sung could resolve by the political approach. Zhuxi had suggested political issues in office. The alternatives for those political issues had basis of the theme, the one that saving people(恤民) is the purpose of politics. However his political ideas and the execution of them had been occsionally collapsed by the complex political structue, the mechanisms of political power, and the sameness and privatization of political geography in Southern Sung. Qingyuandanghuo(慶元黨禍) was the final stage of his political frustration, with the result that it led to the failure of Zhuxi's taoxuezhengzhi and interrupted the tradition of taoxue(道學) for the time being.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.497-510
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• 2022

Agricultural reservoirs are essential structures for water supplies during dry period in the Korean peninsula, where water resources are temporally unequally distributed. For efficient water management, systematic and effective monitoring of medium-small reservoirs is required. Synthetic Aperture Radar (SAR) provides a way for continuous monitoring of those, with its capability of all-weather observation. This study aims to evaluate the applicability of SAR in monitoring medium-small reservoirs using Sentinel-1 (10 m resolution) and Capella X-SAR (1 m resolution), at Chari (CR), Galjeon (GJ), Dwitgol (DG) reservoirs located in Ulsan, Korea. Water detected results applying Z fuzzy function-based threshold (Z-thresh) and Chan-vese (CV), an object detection-based segmentation algorithm, are quantitatively evaluated using UAV-detected water boundary (UWB). Accuracy metrics from Z-thresh were 0.87, 0.89, 0.77 (at CR, GJ, DG, respectively) using Sentinel-1 and 0.78, 0.72, 0.81 using Capella, and improvements were observed when CV was applied (Sentinel-1: 0.94, 0.89, 0.84, Capella: 0.92, 0.89, 0.93). Boundaries of the waterbody detected from Capella agreed relatively well with UWB; however, false- and un-detections occurred from speckle noises, due to its high resolution. When masked with optical sensor-based supplementary images, improvements up to 13% were observed. More effective water resource management is expected to be possible with continuous monitoring of available water quantity, when more accurate and precise SAR-based water detection technique is developed.

• Journal of Internet Computing and Services
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• v.25 no.1
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• pp.99-107
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• 2024

Along with economic growth and industrial development, there is an increasing demand for various electronic components and device production of semiconductor, SMT component, and electrical battery products. However, these products may contain foreign substances coming from manufacturing process such as iron, aluminum, plastic and so on, which could lead to serious problems or malfunctioning of the product, and fire on the electric vehicle. To solve these problems, it is necessary to determine whether there are foreign materials inside the product, and may tests have been done by means of non-destructive testing methodology such as ultrasound ot X-ray. Nevertheless, there are technical challenges and limitation in acquiring X-ray images and determining the presence of foreign materials. In particular Small-sized or low-density foreign materials may not be visible even when X-ray equipment is used, and noise can also make it difficult to detect foreign objects. Moreover, in order to meet the manufacturing speed requirement, the x-ray acquisition time should be reduced, which can result in the very low signal- to-noise ratio(SNR) lowering the foreign material detection accuracy. Therefore, in this paper, we propose a five-step approach to overcome the limitations of low resolution, which make it challenging to detect foreign substances. Firstly, global contrast of X-ray images are increased through histogram stretching methodology. Second, to strengthen the high frequency signal and local contrast, we applied local contrast enhancement technique. Third, to improve the edge clearness, Unsharp masking is applied to enhance edges, making objects more visible. Forth, the super-resolution method of the Residual Dense Block (RDB) is used for noise reduction and image enhancement. Last, the Yolov5 algorithm is employed to train and detect foreign objects after learning. Using the proposed method in this study, experimental results show an improvement of more than 10% in performance metrics such as precision compared to low-density images.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.241-247
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• 2001

Boundary line method was adopted to analyze the relationships between rice yield and meteorological conditions during rice growing period. Boundary lines of yield responses to mean temperature($T_a$) and sunshine hour( $S_{h}$) and diurnal temperature range($T_r$) were well-fitted to hyperbolic functions of f($T_a$) =$$\beta$_{0t}$(1-EXP(-$$\beta$_{1t}$ $\times$ ($T_a$) ) and f( $S_{h}$)=$$\beta$_{0t}$((1-EXP($$\beta$_{1t}$$\times$ $S_{h}$)), to quadratic function of f($T_r$) =$\beta$$_{0r}$(1-($T_r$ 1r)$^2$), respectively. to take into account to, the sterility caused by low temperature during reproductive stage, cooling degree days [$T_c$ =$\Sigma$(20-$T_a$] for 30 days before heading were calculated. Boundary lines of yield responses to $T_c$ were fitted well to exponential function of f($T_c$) )=$\beta$$_{0c}$exp(-$$\beta$_{1c}$$\times$$T_c$ ). Excluding the constants of $\beta$$_{0s}$ from the boundary line functions, formed are the relative function values in the range of 0 to 1. And these were used as yield indices of the meteorological elements which indicate the degree of influence on rice yield. Assuming that the meteorological elements act multiplicatively and independently from each other, meteorological yield index (MIY) was calculated by the geometric mean of indices for each meteorological elements. MIY in each growth period showed good linear relationship with rice yield. The MIY's during 31 to 45 days after transplanting(DAT) in vegetative stage, during 30 to 16 days before heading (DBH) in reproductive stage and during 20 days after heading (DAH) in ripening stage showed greater explainablity for yield variation in each growth stage. MIY for the whole growth period was calculated by the following three methods of geometric mean of the indices for vegetative stage (MIVG), reproductive stage (HIRG) and ripening stage (HIRS). MI $Y_{I}$ was calculated by the geometric mean of meteorological indices showing the highest determination coefficient n each growth stage of rice. That is, (equation omitted) was calculated by the geometric mean of all the MIY's for all the growth periods devided into 15 to 20 days intervals from transplanting to 40 DAH. MI $Y_{III}$ was calculated by the geometric mean of MIY's for 45 days of vegetative stage (MIV $G_{0-45}$ ), 30 days of reproductive stage (MIR $G_{30-0}$) and 40 days of ripening stage (MIR $S_{0-40}$). MI $Y_{I}$, MI $Y_{II}$ and MI $Y_{III}$ showed good linear relationships with grain yield, the coefficients of determination being 0.651, 0.670 and 0.613, respectively.and 0.613, respectively.