• KIPS Transactions on Computer and Communication Systems
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• v.12 no.3
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• pp.103-110
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• 2023

With the spread of the Internet, anonymous communities emerged along with the activation of communities for communication between people, and many users are doing harm to others, such as posting aggressive posts and leaving comments using anonymity. In the past, administrators directly checked posts and comments, then deleted and blocked them, but as the number of community users increased, they reached a level that managers could not continue to monitor. Initially, word filtering techniques were used to prevent malicious writing from being posted in a form that could not post or comment if a specific word was included, but they avoided filtering in a bypassed form, such as using similar words. As a way to solve this problem, deep learning was used to monitor posts posted by users in real-time, but recently, the community uses words that can only be understood by the community or from a human perspective, not from a general Korean word. There are various types and forms of characters, making it difficult to learn everything in the artificial intelligence model. Therefore, in this paper, we proposes a preprocessing technique in which each character of a sentence is imaged using a CNN model that learns the consonants, vowel and spacing images of Korean word and converts characters that can only be understood from a human perspective into characters predicted by the CNN model. As a result of the experiment, it was confirmed that the performance of the LSTM, BiLSTM and CNN-BiLSTM models increased by 3.2%, 3.3%, and 4.88%, respectively, through the proposed preprocessing technique.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.4
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• pp.301-307
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• 2010

Purpose: The objectives of the current study are to assess the accuracy of X-Ray Micro Computed Tomography (microCT) in measuring enamel thickness and to evaluate enamel thickness in maxillary incisors of Koreans. Materials and methods: Five maxillary incisors were embedded in resin block. These teeth were longitudinally sectioned labiolingually through the medial axis. After polishing, the teeth were scanned using a microCT (X-EYE SYSTEM; DRGEM, Seoul, Korea). On a scanning electron microscope (S-4300; Hitachi, Tokyo, Japan) (${\times}20$) and a microCT, nearly identical planes were reconstructed. In each tooth, the thickness of labial enamel was measured 1, 3 and 5 mm above the cementoenamel junction (CEJ). Thus, the accuracy of the microCT was evaluated. In addition, using 26 maxillary central incisors and 11 maxillary lateral incisors, in the medial axis and 2 mm remote areas mesially and distally from the medial axis, the thickness of labial enamel was measured 1, 3 and 5 mm above the CEJ along the long axis of the teeth. Results: Measurements from nearly identical planes in physical and microCT sections differed by 3.81%. An independent t-test was performed and this showed that there were no significant differences in the measurements between the two methods. Mean values of labial enamel thickness in maxillary central incisors 1, 3 and 5 mm above the CEJ were $0.32{\pm}0.01$, $0.50{\pm}0.0.2$ and $0.70{\pm}0.02\;mm$, respectively. Mean values of labial enamel thickness in maxillary lateral incisors 1, 3 and 5 mm above the CEJ were $0.30{\pm}0.01$, $0.55{\pm}0.03$ and $0.80{\pm}0.02\;mm$, respectively. Conclusion: In measuring enamel thickness, microCT is one of useful way of measurement. So according to the results of this research, when restoring a porcelain laminate veneer on maxillary incisors in Koreans, careful consideration is needed in the amount of enamel reduction.

• Therapeutic Science for Rehabilitation
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• v.9 no.1
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• pp.24-44
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• 2020

Objective : To develop an occupation-based bilateral upper extremity training protocol that can be effectively applied in a medical setting Methods : The research process using the delphi technique was carried out in 3 stages. The first stage was an open questionnaire development stage, The first draft is prepared through literature review and open questions were developed through preliminary research based on the draft. The second stage was the delphi survey. Based on the responses of the experts obtained through the open Delphi survey, the adequacy of the training protocol was shown on a Likert 5 point scale. The items were edited and deleted, reconstructed by analyzing the mean and standard deviation, stability, convergence degree, consensus, and content validity ratio through the questionnaire. The third step was the completion of the protocol. After discussions between researchers, the finalized protocol contents were reorganized to complete the occupation-based bilateral upper extremity training protocol for medical setting. Results : The final protocol consisted of 9 items across 3 areas in the occupation-based intervention selection domain and 81 items across 4 areas in the bilateral upper extremity training domain, intervention period, and evaluation. Conclusions : This study suggests an evidence-based method that collects the opinions of occupational therapists in order to use occupation-based activities as interventions in a situation that currently sees occupational therapy primarily performed in hospitals. It is also meaningful that the bilateral upper extremity training can be applied effectively in clinical situations by concretely presenting.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.581-592
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• 2003

The aim of this study was to evaluate the effect of chemo-mechanical caries removal system($Carisolv^{TM}$, Medi Team, Sweden) for resin adhesion to carious primary and permanent dentin compared with conventional drilling method. The buccal surface of 92 primary molars and 92 permanent molars were used. Exposed dentins were occurred artificial caries. 32 tooth of primary molars and 32 tooth of permanent molars were prepared to observe treated dentin surface with $Carisolv^{TM}$ and conventional drilling method by SEM. Other tooth were prepared to measure resin-dentin shear bonding strength according to caries removal methods and dentin adhesive system. Two adhesive systems and a composite resin were used; single bonding agent(Scotchbond Multi-Purpose Plus, 3M) and self-etching bonding system(Prompt L-pop, 3M ESPE), and a composite resin (Z-250, 3M). The results were as follows : 1. The removal effect of carious dentin on $Carisolv^{TM}$ was stronger on the primary dentin than that to permanent dentin, and dentin surface became rougher with treated $Carisolv^{TM}$ than drilling method. 2. Acid-etched dentin surfaces were showed smoothening without smear layer. 3. In specimen applied single bonding system hybrid layer and adhesive layer were $2-4{\mu}m$ and $10-15{\mu}m$ in thickness, whereas self-etching bonding system were showed only thin hybrid layer($1-2{\mu}m$). 4. The shear bonding strength of group applied single bonding agent was higher than that applied self-etching priming system(P<0.05). 5. The shear bonding strength of group applied $Carisolv^{TM}$ and self-etching priming system were slightly higher than that applied conventional drilling method and self-etching priming system(P>0.05).

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.72-81
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• 2024

Purpose: This study aimed to assess the marginal and internal fit of 3-unit monolithic zirconia fixed partial dentures (FPDs) fabricated via computer-aided design and computer-aided manufacturing (CAD/CAM) from solid working casts and removable die system. Materials and Methods: The tooth preparation protocol for a zirconia crown was executed on the mandibular right first premolar and mandibular right first molar, with the creation of a reference cast featuring an absent mandibular right second premolar. The reference cast was duplicated using polyvinyl siloxane impression, from which 20 working casts were fabricated following typical dental laboratory procedures. For comparative analysis, 10 FPDs were produced from a removable die system (RD group) and the remaining 10 FPDs from the solid working casts (S group). The casts were digitized using a dental desktop scanner to establish virtual casts and design the FPDs using CAD. The definitive 3-unit monolithic zirconia FPDs were fabricated via a CAM milling process. The seated FPDs on the reference cast underwent digital evaluation for marginal and internal fit. The Mann-Whitney U test was applied for statistical comparison between the two groups (α = 0.05). Results: The RD group showed significantly higher discrepancies in fit for both premolars and molars compared to the S group (P < 0.05), particularly in terms of marginal and occlusal gaps. Color mapping also highlighted more significant deviations in the RD group, especially in the marginal and occlusal regions. Conclusion: The study found that the discrepancies in marginal and occlusal fits of 3-unit monolithic zirconia FPDs were primarily associated with those fabricated using the removable die system. This indicates the significant impact of the fabrication method on the accuracy of FPDs.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

• Journal of The Korean Association For Science Education
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• v.36 no.2
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• pp.203-219
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• 2016

The purpose of this paper was analyzing the contents of life science area in elementary science textbooks according to Korean science curricula change to get suggestions for the advancement of science curriculum. The framework of content analysis was developed by revising TIMSS 2015 life science evaluation framework. The results of this research were as follows: 'The differences of living things and non-living things appearing in the first grade mostly were not included in the 1st, the 6th and the 2009 revised curricula. Contents emphasizing rural life were appeared from 'Teaching themes period' to the 2nd curriculum period, disappeared from the 3rd curriculum period until the 2009 revised curriculum. Contagious disease was emphasized in all elementary grades in the 1st curriculum period, which reflected a social phenomena emphasizing health and hygiene after the Korean War. Mostly fungus was included until the 7th curriculum period and bacteria and virus were added from the 2007 revised curriculum period. The way of improving health was emphasized continuously.' The differences of living things and non-living things should be included in elementary science curriculum for the correct 'life' concept formation of elementary students. 'Strategies for helping the living of descendants' and 'the heredity of animal and plant' which were appeared in the lower grades, should be included at the higher grades with greater depth. The incoming elementary science textbooks also need to include science contents about evolution in greater depth, along with human health.

• The KIPS Transactions:PartA
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• v.10A no.5
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• pp.469-478
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• 2003

Internet information search engines using web robots visit servers conneted to the Internet periodically or non-periodically. They extract and classify data collected according to their own method and construct their database, which are the basis of web information search engines. There procedure are repeated very frequently on the Web. Many search engine sites operate this processing strategically to become popular interneet portal sites which provede users ways how to information on the web. Web search engine contacts to thousands of thousands web servers and maintains its existed databases and navigates to get data about newly connected web servers. But these jobs are decided and conducted by search engines. They run web robots to collect data from web servers without knowledge on the states of web servers. Each search engine issues lots of requests and receives responses from web servers. This is one cause to increase internet traffic on the web. If each web server notify web robots about summary on its public documents and then each web robot runs collecting operations using this summary to the corresponding documents on the web servers, the unnecessary internet traffic is eliminated and also the accuracy of data on search engines will become higher. And the processing overhead concerned with web related jobs on web servers and search engines will become lower. In this paper, a monitoring system on the web server is designed and implemented, which monitors states of documents on the web server and summarizes changes of modified documents and sends the summary information to web robots which want to get documents from the web server. And an efficient web robot on the web search engine is also designed and implemented, which uses the notified summary and gets corresponding documents from the web servers and extracts index and updates its databases.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.46-53
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• 2010

Purpose: The static image of nuclear medicine study should be acquired without a motion, however, it is difficult to acquire static image without movement for the serious patients, advanced aged patients. These movements cause decreases in reliability for quantitative and qualitative analysis, therefore re-examination was inevitable in the some cases. Consequently, in order to improve the problem of motion artifacts, the authors substituted the dynamic acquisition technique for the static acquisition, using motion correction. Materials and Methods: A capillary tube and IEC body phantom were used. First, the static image was acquired for 60 seconds while the dynamic images were acquired with a protocol, 2 sec/frame${\times}$30 frames, under the same parameter and the frames were summed up into one image afterwards. Also, minimal motion and excessive motion were applied during the another dynamic acquisition and the coordinate correction was applied towards X and Y axis on the frames where the motion artifact occurred. But the severe blurred images were deleted. Finally, the resolution and counts were compared between the static image and the summed dynamic images which before and after applying motion correction, and the signal of frequency was analysed after frequency spatial domain was transformed into 2D FFT. Supplementary examination, the blind test was performed by the nuclear medicine department staff. Results: First, the resolution in the static image and summed dynamic image without motion were 8.32 mm, 8.37 mm on X-axis and 8.30 mm, 8.42 mm on Y-axis, respectively. The counts were 484 kcounts, 485 kcounts each, so there was nearly no difference. Secondly, the resolution in the image with minimal motion applying motion correction was 8.66 mm on X-axis, 8.85 mm on Y-axis and had 469 kcounts while the image without motion correction was 21.81 mm, 24.02 mm and 469 kcounts in order. So, this shows the image with minimal motion applying motion correction has similar resolution with the static image. Lastly, the resolution in the images with excessive motion applying motion correction were 9.09 mm on X-axis, 8.83 mm on Y-axis and had 469 kcounts while the image without motion correction was 47.35 mm, 40.46 mm and 255 kcounts in order. Although there was difference in counts because of deletion of blurred frames, we could get similar resolution. And when the image was transformed into frequency, the high frequency was decreased by the movement. However, the frequency was improved again after motion correction. In the blind test, there was no difference between the image applying motion correction and the static image without motion. Conclusion: There was no significant difference between the static image and the summed dynamic image. This technique can be applied to patients who may have difficulty remaining still during the imaging process, so that the quality of image can be improved as well as the reliance for analysis of quantity. Moreover, the re-examination rate will be considerably decreased. However, there is a limit of motion correction, more time will be required to successfully image the patients applying motion correction. Also, the decrease of total counts due to deletion of the severe blurred images should be calculated and the proper number of frames should be acquired.

• Survey Research
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• v.6 no.1
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• pp.1-38
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• 2005

Considering the importance of corruption index measurement model and the diffusion of popular awareness about the importance of anti-corruption, this research compared and analyzed existing corruption index measurement models. This paper has selected "Anti-Corruption Index model(ACI model)" that was developed by Seoul Development Institute and "CCEJ's Corruption Index model" which is under use by the Citizens' Coaltion for Economic Justice. These two models were analyzed in terms of appropriateness of 'the indicator and index choice method', 'the research design' and 'the use of statistical data'. This analysis shows that two models have some problems. First, at the level of indicator and index choice method, the indicators of CCEJ's corruption index model is too atomized and redundant. As not putting weight of indicator, it did not consider importance of each indicator. Citizens who evaluated the level of corruption didn't participate in the weight evaluation team, which results in failure of the model to reflect the citizens' opinion. Also, because the question about Seoul Metropolis' corruption level is not included, it is not detected difference between real corruption level and perceptive corruption level. Second, in terms of appropriateness of research design, the sample of the CCEJ' corruption index model is too small to get credibility. The objectivity of research method seems to be low because survey was performed by exit interview. In addition, 38 items are overfull in the questionnire of CCEJ's corruption index model compare to 13 items in ACI model. Also, in making up questions, the terms are redundant and unobvious. Third, in regarding with feasibility of the statistical data, the CCEJ's corruption index model uses regulation data for disciplinary punishment of 25 local governments in Seoul from 1995 to 1999. But, it is common ideas of scholars that statistical data indicates the tip of an iceberg in corruption. So for using a statistical data, it needs a data of enough quantity and has a high level credibility. In addition, objective method of giving weight is not developed. In this point of view, the use of statistical data has some limits. To solve this problem, ① objective data should be included in the indicators, ② various indicators should be developed and ③ a method of giving weight should be improved.