• The Journal of Advanced Prosthodontics
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• v.16 no.4
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• pp.231-243
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• 2024

PURPOSE. The objective of the study was to analyze the impact of cement, bonding pretreatment, and ceramic abutment material on the overall color results of CAD-CAM ceramic crowns bonded to titanium-based hybrid abutments. MATERIALS AND METHODS. For single implant restoration of a maxillary lateral incisor a total of 51 CAD-CAM-fabricated monolithic lithium disilicate crowns were fabricated and subsequently bonded onto 24 lithium disilicate Ti-base abutments, 24 zirconia Ti-base abutments and 3 resin abutment replicas as a control group. The 48 copings were cemented with three definitive and one provisional cement on both grit-blasted and non-blasted Ti-bases. The color of each restoration and surrounding artificial gingiva was measured spectrophotometrically at predefined measuring points and the CIELAB (ΔE_ab) color scale values were recorded. RESULTS. The color outcome of ceramic crowns bonded to hybrid abutments and soft tissues was affected differently by cements of different brands. Grit-blasting of Ti-bases prior to cementing CAD-CAM copings affected the color results of allceramic crowns. There was a significant difference (P = .038) for the median ΔE value between blasted and non-blasted reconstructions at the cervical aspect of the crown. Full-ceramic crowns on zirconia Ti-base abutments exhibited significantly lower ΔE values below the threshold of visibility (ΔE 1.8). In all subcategories tested, the use of a highly opaque temporary cement demonstrated the lowest median ΔE for both the crown and the artificial gingiva. CONCLUSION. Various cements, core ceramic materials and airborne particle abrasion prior to bonding can adversely affect the color of Ti-base supported ceramic crowns and peri-implant soft tissue. However, zirconia CAD-CAM copings and an opaque cement can effectively mask this darkening.

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.1-8
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• 2007

The purpose of this study was to investigate whether there were any changes in taste sensitivity with recurrent aphthous ulceration. Nintyseven subjects(25 males and 72 females) were included for the study and they were categorized into 2 groups(recurrent aphthous ulceration 27 persons, control 70 persons), recurrent aphthous ulceration group was investigated in the department of Oral Medicine, College of Dentistry, Pusan National University from April, 2005 to August, 2006 and control group was investigated in the clinic at Incheon city from June, 2006 to August, 2006. The electrical taste thresholds were measured using an electrogustometer of the 4 different sites(tongue tip, tongue lateral, circumvallate papilla and soft palate) in oral cavity. The results were as follows ; 1. The electrical taste threshold showed significant lower in the RAU group. 2. The electrical taste threshold showed significant lower in female group, and showed significant lower except soft palate in male group of the RAU group. 3. The electrical taste threshold showed a tendency to increase in all site of the multiple RAU group, but there were no significant differences. 4. The electrical taste threshold showed a tendency to increase in tongue lateral of the acute RAU group, and showed a tendency to increase in tongue tip, circumvallate papilla, soft palate of the chronic RAU group. 5. After treatment, electrical taste threshold was significant increase than initial visit in the RAU group. 6. After treatment, NAS showed a tendency to decrease in the RAU group.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.1
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• pp.105-122
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• 2022

According to the statistics about the fatal crashes that have occurred on the expressways for the last 5 years, those who died on the shoulders of the road has been as 3 times high as the others who died on the expressways. It suggests that the crashes on the shoulders of the road should be fatal, and that it would be important to prevent the traffic crashes by cracking down on the vehicles intruding the shoulders of the road. Therefore, this study proposed a method to detect a vehicle that violates the shoulder lane by using the Faster R-CNN. The vehicle was detected based on the Faster R-CNN, and an additional reading module was configured to determine whether there was a shoulder violation. For experiments and evaluations, GTAV, a simulation game that can reproduce situations similar to the real world, was used. 1,800 images of training data and 800 evaluation data were processed and generated, and the performance according to the change of the threshold value was measured in ZFNet and VGG16. As a result, the detection rate of ZFNet was 99.2% based on Threshold 0.8 and VGG16 93.9% based on Threshold 0.7, and the average detection speed for each model was 0.0468 seconds for ZFNet and 0.16 seconds for VGG16, so the detection rate of ZFNet was about 7% higher. The speed was also confirmed to be about 3.4 times faster. These results show that even in a relatively uncomplicated network, it is possible to detect a vehicle that violates the shoulder lane at a high speed without pre-processing the input image. It suggests that this algorithm can be used to detect violations of designated lanes if sufficient training datasets based on actual video data are obtained.

• The KIPS Transactions:PartB
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• v.8B no.6
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• pp.693-698
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• 2001

Noisy data are often fitted using a smoothing parameter, controlling the importance of two objectives that are opposite to a certain extent. One of these two is smoothness and the other is closeness to the input data. The optimal value of this parameter minimizes the error of the result. This optimum cannot be found exactly, simply because the exact data are unknown. This paper propose the threshold value for noise reduction based on wavelet-thresholding. In the proposed method PSNR results show that the threshold value performs excellently in comparison with conventional methods without knowing the noise variance and volume of signal.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.1
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• pp.64-75
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• 2003

Medical image segmentation is the process by which an original image is partitioned into some homogeneous regions like bones, soft tissues, etc. This study demonstrates an automatic medical image segmentation technique based on independent component analysis. Independent component analysis is a generalization of principal component analysis which encodes the higher-order dependencies in the input in addition to the correlations. It extracts statistically independent components from input data. Use of automatic medical image segmentation technique using independent component analysis under the assumption that medical image consists of some statistically independent parts leads to a method that allows for more accurate segmentation of bones from CT data. The result of automatic segmentation using independent component analysis with square test data was evaluated using probability of error(PE) and ultimate measurement accuracy(UMA) value. It was also compared to a general segmentation method using threshold based on sensitivity(True Positive Rate), specificity(False Positive Rate) and mislabelling rate. The evaluation result was done statistical Paired-t test. Most of the results show that the automatic segmentation using independent component analysis has better result than general segmentation using threshold.

• Physical Therapy Rehabilitation Science
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• v.2 no.1
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• pp.27-30
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• 2013

Objective: Low back pain is a primary of source of dysfunction and economic costs. Gluteus medius muscle co-activation and activity pattern change caused the low back pain. Active release technique (ART) is a patented, non-invasive, soft tissue treatment process that both locates and breaks down the scar tissue and adhesions. The purpose of this study was to assess the effects on chronic low back pain using ART on gluteus medius so that suggest usable treatment method for treating chronic low back pain. Design: One group pretest-posttest design. Methods: Twelve patients with chronic low back pain were participated in this study. Subjects in ART group were received 2 times a week for 3 weeks treatments with either ART on gluteus medius muscle trigger points. Outcome measures were conducted by pain intensity with a pain visual analogue scale and pressure pain threshold on gluteus medius. Results: Completion of the intervention, the visual analogue scale was decreased in ART group (p<0.05). Also pressure pain threshold was decreased in ART group (p<0.05). Conclusions: Our results suggest that the response to ART may be usable to treat low back pain. ART was presented to reduce pain level of low back in people with chronic low back pain. Further study is required to management for low back pain due to gluteus medius and more ART study.

• Journal of Information Processing Systems
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• v.14 no.4
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• pp.941-947
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• 2018

Since the amplitudes of spin echo train in nuclear magnetic resonance logging (NMRL) are small and the signal to noise ratio (SNR) is also very low, this paper puts forward an improved de-noising algorithm based on wavelet transformation. The steps of this improved algorithm are designed and realized based on the characteristics of spin echo train in NMRL. To test this improved de-noising algorithm, a 32 points forward model of big porosity is build, the signal of spin echo sequence with adjustable SNR are generated by this forward model in an experiment, then the median filtering, wavelet hard threshold de-noising, wavelet soft threshold de-noising and the improved de-noising algorithm are compared to de-noising these signals, the filtering effects of these four algorithms are analyzed while the SNR and the root mean square error (RMSE) are also calculated out. The results of this experiment show that the improved de-noising algorithm can improve SNR from 10 to 27.57, which is very useful to enhance signal and de-nosing noise for spin echo train in NMRL.

• Journal of KIISE:Information Networking
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• v.29 no.4
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• pp.352-357
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• 2002

In CDMA cellular systems, a handoff process in which the mobile station (MS) can communicate with the target base station without interrupting the communication with the current base station makes contact with the target base station before it breaks with the station it is operating on. An MS requests a soft handoff to a neighbor base station (BS) whenever the pilot strength received from the neighbor BS exceeds the handoff threshold, even though the MS may not actually be approaching to the neighbor BS. Since two traffic channels have to assign to an MS during the soft handoff period, the utilization of traffic channels is wasted. Thus, an analysis of handoff rate is a key to understand and evaluate channel efficiency. In this paper, a simple and straightforward mathematical analysis method for evaluate obtaining direction-based soft handoff rate and the number of handoff calls in CDMA cellular systems is proposed.

• Journal of Oral Medicine and Pain
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• v.33 no.2
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• pp.133-145
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• 2008

The purpose of this study was to investigate the taste sensitivity in patients with oral mucosal diseases(Oral lichen planus(OLP), Recurrent apthous ulcer(RAU)) using electrogustometer. One hundred and seventy three subjects were included for the study and they were categorized into 2 groups(control 100, patient 73) and patient group was investigated in the Department of Oral Medicine, Pusan National University Hospital from April, 2005 until January, 2007. Control group was investigated in the clinics at Inchen Metroplitan city and Cheongju city from February to August, 2006. The electrical taste thresholds were measured by using an electrogustometer for the 4 different sites(tongue tip, tongue lateral, circumvallate papilla and soft palate) in oral cavity. The results were as follows ; 1. The electrical taste threshold in patient group was significantly decreased than that in the control group(p<0.001). 2. The electrical taste threshold, in terms of the chronicity and lesion multiplicity, was not significantly changed in patient group. 3. The electrical taste threshold was not significantly changed in Dexan only and Dexan+Prs combination treated group. 4. The electrical taste threshold, in terms of treatment progress(no response vs half response vs complete response), was not significantly changed. However subjective index which was determined by NAS(Numerical Analogy Scale) was significantly increased in no response group but significantly decreased in complete response group(p<0.001)

• Journal of Oral Medicine and Pain
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• v.33 no.1
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• pp.67-73
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• 2008

To investigate the change of taste sensitivity which follows after treatment for xerostomia, from September, 2006 to July, 2007, we categorized the patients, who were diagnosed as xerostomia in Oral Medicine, College of Dentistry, Busan National University, as subject group and from September, 2007 to December. The patients who were not diagnosed as systemic disease were categorized as control group. The results were as follows ; 1. Taste threshold comparison showed the differences at tongue lateral, tongue tip, circumvallate papilla between subject and control. 2. Taste threshold comparison showed no difference in male between subject and control. 3. Taste threshold comparison showed decrease in whole tongue except soft palate in female. 4. Taste threshold comparison showed no difference between first and second visit, but there was a tendency to change in circumvallate papilla.