• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.111-111
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• 2002

Purpose： This study is to compare the distinct brain activation between implicit and explicit memory retrieval tasks using a non-invasive blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging(fMRI). Materials ＆ Methods： We studied seven right-handed, healthy volunteers aged 21-25 years(mean；22 years) were scanned under a 1.5T Signa Horizon Echospeed MR imager(GE Medical Systems, Milwaukee, U.S.A.). During the implicit and explicit memory retrieval tasks of previously teamed words under the conceptual processing, we acquired fMRI data using gradient-echo EPI with 50ms TE, 3000ms TR, 26cm${\times}$26cm field-of-view, 128${\times}$128 matrix, and ten slices(6mm slice thickness, 1 mm gap) parallel to the AC-PC(anterior commissure and posterior commissure) line. By using the program of statistical parametric mapping(SPM99), functional activation maps were reconstructed and quantified.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.45
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• pp.121-133
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• 1998

This study suggests an efficient algorithm for updating discovered association rules in large database, because a database may allow frequent or occasional updates, and such updates may not only invalidate some existing strong association rules, but also turn some weak rules into strong ones. FUP and DMI update efficiently strong association rules in the whole updated database reusing the information of the old large item-sets. Moreover, these algorithms use a pruning technique for reducing the database size in the update process. This study updates strong association rules efficiently in the whole updated database reusing the information of the old large item-sets. An updating algorithm that is suggested in this study generates the whole candidate item-sets at once in an incremental database in view of the fact that it is difficult to find the new set of large item-sets in the whole updated database after an incremental database is added to the original database. This method of generating candidate item-sets is different from that of FUP and DMI. After generating the whole candidate item-sets, if each item-set in the whole candidate item-sets is large at an incremental database, the original database is scanned and the support of each item-set in the whole candidate item-sets is updated. So, the whole large item-sets in the whole updated database is found out. An updating algorithm that is suggested in this study does not use a pruning technique for reducing the database size in the update process. As a result, an updating algoritm that is suggested updates fast and efficiently discovered large item-sets.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.3
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• pp.353-360
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• 2012

This paper describes a SLAM method which estimates landmark locations and robot pose simultaneously. The particle filter can deal with nonlinearity of robot motion as well as the non Gaussian property of robot motion uncertainty and sensor error. The state to be estimated includes the locations of landmarks in addition to the robot pose. In the experiment, four beacons which transmit ultrasonic signal are used as landmarks. The robot receives the ultrasonic signals from the beacons and detects the distance to them. The method uses rang scanning sensor to build geometric feature of the environment. Since robot location and heading are estimated by the particle filter, the scanned range data can be converted to the geometric map. The performance of the method is compared with that of the deadreckoning and trilateration.

• Journal of Technologic Dentistry
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• v.42 no.1
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• pp.9-16
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• 2020

Purpose: The purpose of this study was to compare the marginal and internal fit of lithium disilicate ceramic inlay produced by heat pressing that inlay pattern made by subtractive manufacturing and additive manufacturing method. Methods: A mandibular lower first molar that mesial occlusal cavity (MO cavity) die was prepared. After fabricating an epoxy resin model using a silicone impression material, epoxy resin die was scanned with a dental model scanner to design an MO cavity inlay. The designed STL pile was used to fabricate wax patterns and resin patterns, and then lithium disilicate ceramic inlays were fabricated using hot-press method. For the measurement of the marginal and internal gap of the lithium disilicate, silicone replica method was applied, and gap was measured through an optical microscope (x 80). Data were tested for significant differences using the Mann-Whitney Utest. Results: The marginal fit was 103.56±9.92㎛ in the MIL-IN group and 81.57±9.33㎛ in the SLA-IN group, with a significant difference found between the two groups (p<0.05). The internal fit was 120.99±17.52㎛ in the MIL-IN group and 99.18±6.65㎛ in the SLA-IN group, with a significant difference found between the two groups (p<0.05). Conclusion: It is clinically more appropriate to apply the additive manufacturing than subtractive manufacturing method in producing lithium disilicate inlay using CAD/CAM system.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.211.1-211.1
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• 2012

The on-orbit test simulation for predicting the instrument directional responsivity was conducted by the Monte Carlo based integrated ray tracing (IRT) computation technique and analytic flux-to-signal conversion algorithms. For the on-orbit test simulation, the Sun model consists of the Lambertian scattering sphere and emitting spheroid rays, the Amon-Ra instrument is a two-channel including a broadband scanning radiometer (energy channel) and an imager with ${\pm}2^{\circ}$ FOV (visible channel). The solar radiation produced by the Sun model is directed to the instrument viewing port and traced through the dual channel optical train. The instrument model is rotated on its rotation axis and this gives a slow scan of the Sun model over the full field of view. The direction of the incident lights are fed with scanned images obtained from the visible channel instrument. The instrument responsivity was computed by the ratio of the incident radiation input to the instrument output. In the radiometric simulation, especially, measured BRDF of the 3D CPC was used for scattering effects on radiometry. With diamond turned 3D CPC inner surface, the anisotropic surface scattering model from the measured data was applied to ray tracing computation. The technical details of the on-orbit test simulation are presented together with field-of-view calibration plan.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.34.1-34.7
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• 2020

Objectives: This study evaluated by using micro-computed tomography (micro-CT) the filling ability and sealer apical extrusion promoted by a new Sealer Injection System (SIS; Angelus) with side openings needle, in comparison with the conventional injection system, associated with a new ready-to-use calcium silicate-based sealer (Bio-C Sealer). Materials and Methods: Acrylic resin models containing a main curved artificial canal and 3 simulated lateral canals in apical, middle and cervical thirds were used. The main root canals were prepared using a rotary system up to size 35.05. The canals were filled with Bio-C sealer by using a single cone technique and the conventional delivery system or SIS. Samples were scanned in micro-CT. The percentage of voids throughout the entire extension of the main root canal and in each third of the lateral canals, besides the apical extrusion of the sealer was calculated. Data were submitted to t-test (p < 0.05). Results: There was no difference between both systems in the main root canals filling. Although the volume percentage of voids was similar in the apical and middle thirds of lateral canals, SIS had the greatest filling ability of the cervical third lateral canal. Moreover, the conventional system showed the highest apical extrusion of the sealer. Conclusions: The conventional and SIS obturation systems had an appropriate filling ability of the main root canal. SIS had the best filling of the cervical third of the lateral canals, besides lower sealer apical extrusion, suggesting its clinical indication.

• The KIPS Transactions:PartD
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• v.15D no.1
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• pp.15-22
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• 2008

In this paper, we propose an efficient algorithm using only one-time database scan. The proposed algorithm creates the bipartite graph which indicates relationship of large items and transactions including the large items. And then we can find large itemsets using the bipartite graph. The bipartite graph is generated when database is scanned to find large items. We can't easily find transactions which include large items in the large database. In the bipartite graph, large items and transactions are linked each other. So, we can trace the transactions which include large items through the link information. Therefore the bipartite graph is a indexed database which indicates inclusion relationship of large items and transactions. We can fast find large itemsets because proposed method conducts only one-time database scan and scans indexed the bipartite graph. Also, it don't generate candidate itemsets.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.4
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• pp.331-338
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• 2008

Ultrasonic testing for welds is widely used to ensure the integrity of facilities in NPPs. Automated ultrasonic testing(AUT) is more consistent than the manual ultrasonic testing(MUT). It can scan welded parts, examines the scanned images, and saves the results as data files. AUT in NPPs is making use of commercial systems, and there has been some difficulties in calibration of the system. An AUT system is developed. It comprises of pulser/receiver, scanner and a control program(SonicWizard). The performance demonstration for piping welds in NPPs and the piping wall thickness measurement on site were conducted to verify this system. The test results of the ultrasonic testing system developed is satisfactory and effective.

• Journal of Nutrition and Health
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• v.35 no.10
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• pp.1053-1059
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• 2002

In post-genome period, the technique for identifying gene expression has been changed to high throughput screening. In the field of molecular nutrition, the need for this technique to clarify molecular function of the specific nutrient is essential. In this study, we have tested the zinc-regulated gene expression in zinc-deficient U937 cells, using cDNA microarray which is the cutting-edge technique to screen large numbers of gene expression simultaneously. The study result can be used for the preliminary gene screening data for clarifying, using monocyte U937 cell line, molecular Zn aspect in atherosclerosis. U937 cells were cultured in Zn-adequate (control, 12 $\mu$M Zn) or Zn-deficient (experimental, 0 $\mu$M Zn) ESMI media during 2 days, respectively. Cells were harvested and RNA was extracted. Total RNA was reverse-transcriptinized and synthesized cDNA probe labeled with Cy-3. fluorescent labeled cDNA probe was applied to microarray slide for hybridization slide, and after then, the slide was scanned using fluorescence scanner. ‘Highly expressed genes’ in Zn-deficient U937 cells, comparing to Zn-adequate group, are mainly about the genes for motility protein, immune system protein, oncogene and tumor suppressor and ‘Less highly expressed genes’ are about the genes for transcription, apoptosis associated protein, cell cycle, and several basic transcription factors. The results of this preliminary study imply the effectiveness of cDNA microarray for expression profiling of a singly nutrient deficiency, specially Zn. Furthur study, using tailored-cDNA array and capillary endothelial cell lines, would be beneficial to clarify molecular Zn function, more in detail.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.236-242
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• 2019

Recently, scanning projects have been carried out in various construction and construction fields for maintenance purposes. The point cloud generated by the scan results is composed of a number of points representing the object to be scanned. The process of extracting the necessary information, including dimensions, from such scan data is called paradox. The reverse engineering process of modeling a point cloud as BIM involves considerable manual work. Owing to the time-consuming reverse engineering nature of the work, the costs increase exponentially when rework requests are made, such as design changes. Reverse engineering automation technology can help improve these problems. On the other hand, the reverse design product is variable depending on the use, and the kind and detail level of the product may be different. This paper proposes the G2BM (Geometry-to-BIM mapping) rule definition method that automatically maps a BIM object from a primitive geometry to a BIM object. G2BM proposes a process definition and a customization method for reverse engineering BIM objects that consider the use case variability.