• Korean Journal of Digital Imaging in Medicine
• /
• v.15 no.1
• /
• pp.55-59
• /
• 2013

Patients who had claustrophobia tend to feel fear when they were scanned by an MRI, CT, PET-CT, or using a gamma camera scan. In this paper, claustrophobic patients were tested to find effective ways by changing patient's positions. For this paper, PET-CT scan in patients who had claustrophobia were used in the prone position. Prone position helped to maintain stable position and to get a h0igh quality of inspection without failure. Thus, as claustrophobic patients were requested taking prone position, they could feel comfortable. In a confined space, prone position for the claustrophobic patients who had a fear of the PET-CT examination would be expected to reduce the failure rate of inspection.

• Journal of Korean Dental Science
• /
• v.17 no.1
• /
• pp.1-13
• /
• 2024

With the advances of digital scanning technology in dentistry, the interests in facial scanning in orthodontics have increased. There are many different manufacturers of facial scanners marketing to the dental practice. How do you know which one will work best for you? What questions should you be asking? We suggest a clinical guideline which may help you make an informed decision when choosing facial scanners. The characteristics of 7 facial scanners were discussed in this article. Here are some considerations for choosing a facial scanner. *Accuracy: For facial scanners to be of real value, having an appropriate camera resolution is necessary to achieve more accurate facial image representation. For orthodontic application, the scanner must create an accurate representation of an entire face. *Ease of Use: Scanner-related issues that impact their ease of use include type of light; scan type; scan time; file type generated by the scanner; unit size and foot print; and acceptance of scans by third-party providers. *Cost: Most of the expenses associated with facial scanning involve the fixed cost of purchase and maintenance. Other expenses include technical support, warranty costs, transmission fees, and supply costs. This article suggests a clinical guideline to make the right choice for facial scanner in orthodontics.

• Geophysics and Geophysical Exploration
• /
• v.12 no.2
• /
• pp.192-198
• /
• 2009

Side scan sonar and SBP (sub-bottom profiler) play a very important role in the survey for seafloor imaging and sub-bottom profiling. In this study, we have acquired side scan sonar and SBP data from the artificial reef area. We applied digital image processing techniques to side scan sonar data in order to improve an image quality. For the enhancement of data quality and image resolution, we applied the typical seismic data processing sequence including gain recovery, muting, spectrum analysis, predictive deconvolution, migration to SBP data. We could easily estimate if artificial reef structures were settled properly and their distribution on the seafloor from the integrated interpretation of side scan sonar and SBP data. From the sampling analysis of seabed sediments, texture filtering of side scan sonar data and SBP data interpretation, we could evaluate the sediment type, distribution and thickness of seafloor sediments in detail.

• The Journal of Korean Academy of Prosthodontics
• /
• v.61 no.4
• /
• pp.379-385
• /
• 2023

With the recent development of digital dentistry, fully digitalized methods for fabricating dentures, using intraoral scans and computer-aided design/computer-aided manufacturing (CAD-CAM), are getting popular. Digital methods have the advantage of simplifying the fabrication process in the clinic and laboratory, supplementing digital data. This case report shows a fully digital fabrication method for interim removable dentures in a patient with anterior tooth loss in which implant placement is impossible or delayed. Interim removable dentures were fabricated using two methods. One method is printing tooth and base parts separately and combining, and the other method is printing the whole denture at one time and coloring on the base part. Afterward, dentures were delivered and adaptation was evaluated using the triple scan technique. The extracted site was scanned intraorally (first scan) and the interim removable denture was digitally scanned both intraorally (second scan) and, after removal extraorally (Third scan). In both method, denture adaptation was shown favorable. We report this case report as both the patient and the operator were satisfied with a simplified process using a fully digital method in the clinic.

• The Journal of Advanced Prosthodontics
• /
• v.14 no.4
• /
• pp.212-222
• /
• 2022

PURPOSE. To evaluate and compare the effect of impression type (conventional vs digital) and the number of implants on the time from the impressions to the generation of working casts of mandibular implant-supported fixed completearch frameworks, as well as on patient satisfaction. MATERIALS AND METHODS. 17 participants, 3 or 4 implants, received 2 types of digital impression methods (DI) and conventional (CI). In DI, two techniques were performed: scanning with the scan bodies (SC) and scanning with a device attached to the scan bodies (SD) (BR 10 2019 026265 6). In CI, the making of a solid index (SI) and open-tray impression (OT) were used. The outcomes were used to evaluate the time and the participant satisfaction with conventional and digital impressions. The time was evaluated through the timing of the time obtained in the workflow in the conventional and digital impression. The effect of the number of implants on time was also assessed. Satisfaction was assessed through a questionnaire based on seven. The Wilcoxon test used to identify the statistical difference between the groups in terms of time. The Mann-Whitney test was used to analyze the relationship between the time and the number of implants. Fisher's test was used to assess the patient satisfaction (P<.05). RESULTS. The time with DI was shorter than with CI (DI, $\tilde{x}=02:58$; CI, $\tilde{x}=31:48$) (P<.0001). The arches rehabilitated with 3 implants required shorter digital impression time (3: $\tilde{x}=05:36$; 4: $\tilde{x}=09:16$) (P<.0001). Regarding satisfaction, the DI was more comfortable and pain-free than the CI (P<.005). CONCLUSION. Digital impressions required shorter chair time and had higher patient acceptance than conventional impressions.

• ETRI Journal
• /
• v.26 no.4
• /
• pp.332-343
• /
• 2004

One of the recent and most significant technical properties can be expressed as "digital convergence," which is helping lead the technical paradigm into a ubiquitous environment. As an initial trial of realizing a ubiquitous environment, the convergence between broadcasting and telecommunication fields is now on the way, where it is required to develop a scalable video coding scheme for one-source and multi-use media. Traditional scalable video coding schemes have, however, limitations for higher stable picture quality especially on the region of interest. Therefore, this paper introduces an adaptive scanning method especially designed for a higher regional-stable picture quality under a ubiquitous video coding environment, which can improve the subjective quality of the decoded video by most-preferentially encoding, transmitting, and decoding the top-priority image information of the region of interest. Thus, the video can be more clearly visible to users. From various simulation results, the proposed scanning method in this paper can achieve an improved subjective picture quality far better than the widely used raster scan order in conventional video coding schemes, especially on the region of interest, and without a significant loss of quality in the left-over region.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.837-840
• /
• 2007

We propose a novel digital driving method for AM-OLED (Active Matrix-Organic Light Emitting Diode) display. Proposed method modulates $V_{DD}$ so that luminance may be weighted in accordance with the bit significance. We can increase the minimum emission time or slower scan circuits are applicable by using proposed method.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2019.05a
• /
• pp.255-256
• /
• 2019

• Journal of Dental Rehabilitation and Applied Science
• /
• v.36 no.1
• /
• pp.29-40
• /
• 2020

Purpose: The purpose of this study was to compare the accuracy of impression taking method using the encoded healing abutment, scan body and pick-up impression coping with different implant angulations. Materials and Methods: Master model was fabricated by 3D printer and three implants were placed into the model with 0°, 10° and 20° mesial angulation. The abutments were secured to each implants and master model was scanned to make a reference model. Group P model was fabricated using pick-up impression copings and model was scanned after securing the abutments. Encoded healing abutment (Group E) and scan body (Group S) were secured on the master model and digital impression was taken using intraoral scanner 15 times each. Each STL files of test groups were superimposed with reference model using best fit alignment and root mean square (RMS) value was analyzed. Results: The RMS values were lowest in Group P, followed by Group S and Group E. Group P showed significant difference with Group S and E (P < 0.05) while there was no significant difference between Group S and E. Correlation between implant angulation and RMS value was significant in Group E (P < 0.05). Conclusion: The pick-up impression coping method showed higher accuracy and there was no significant difference in accuracy between the healing abutment and the scan body. The clinical use of the encoded healing abutment is possible, but it should be used with caution in the case of angulated implant.

• Progress in Medical Physics
• /
• v.21 no.3
• /
• pp.281-290
• /
• 2010

Cone-beam digital tomosynthesis (CBDT) has greatly been paid attention in the image-guided radiation therapy because of its attractive advantages such as low patient dose and less motion artifact. Image quality of tomograms is, however, dependent on the imaging conditions such as the scan angle (${\beta}_{scan}$) and the number of projection views. In this paper, we describe the principle of CBDT based on filtered-backprojection technique and investigate the optimization of imaging conditions. As a system performance, we have defined the figure-of-merit with a combination of signal difference-to-noise ratio, artifact spread function and floating-point operations which determine the computational load of image reconstruction procedures. From the measurements of disc phantom, which mimics an impulse signal and thus their analyses, it is concluded that the image quality of tomograms obtained from CBDT is improved as the scan angle is wider than 60 degrees with a larger step scan angle (${\Delta}{\beta}$). As a rule of thumb, the system performance is dependent on $\sqrt{{\Delta}{\beta}}{\times}{\beta}^{2.5}_{scan}$. If the exact weighting factors could be assigned to each image-quality metric, we would find the better quantitative imaging conditions.