• Elastomers and Composites
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• v.36 no.4
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• pp.237-245
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• 2001

A study was made on the chemical treatment of silica and silane coupling agents, bistriethox ysilylpropyltetrasulfide(Si 69) and ${\gamma}$-mercaptopropyltrimethoxy silane (MPS) for reinforcement of silica formulation. The effects of chemical treatment method and the most popular two coupling agents were examined. The results clearly indicate that the wet method, coupling agent is combined chemically with the silica prior to mixing, has more dispersion, wetting ability, dynamic properties and stability than the dry method, coupling agent is premixed directly with the silica. The mixing was done using a bench-type kneader having two mixing cam and a two-roll mill, under approximately similar conditions. The physical properties of SBR vulcanizates give rise to marked improvements by addition of Si 69 and MPS in comparison with without silane coupling agents. The optimum amount of Si 69 and MPS was 2 w/w% by experiments in the dry method but was 4 w/w% by EA and TGA analysis in the wet method.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.166-172
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• 2018

In case of the treatment of maxillary anterior teeth, it should be taken into account the proper morphology, arrangement and color satisfying patient's esthetic demands. For this purpose, facial composition, dentofacial composition, dental composition and dentogingival composition should be considered making diagnosis and treatment plan in an esthetic point of view. In adjustable temporary crown state, careful evaluation and correction of the esthetic and functional aspect were performed, and the definite restoration was reproduced using double scan.

• Journal of Technologic Dentistry
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• v.34 no.2
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• pp.105-111
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• 2012

Purpose: The purpose this study was to evaluate the marginal fitness of metal copings fabricated using rapid prototyping method and to compare the fitness with copings by conventional method. Then clinical availability of fixed dental prostheses (FDPs) fabricated using rapid prototyping method shall be confirmed based on marginal fitness. Methods: Ten same cases of3 unit FDPs epoxy models (abutment teeth 14 and 16) were manufactured. Each of ten epoxy models were scanned by 3shape D-700 scanner to be designed by experienced technician, and photopolymer 3 unit FDPs were fabricated using rapid prototyping methodand fabricated using Lost wax technique (LW) with same models. Marginal fitness of 3 unit FDPs were measured by silicone replica technique. T-test of independent sample for statistical analysis was executed with SPSS 12.0K for Windows. (${\alpha}$=.05) Results: Significantly higher mean (SD) marginal fitness (P<.000) were observed in the RP group $(95.9(18.0){\mu}m$ compared to the conventionally LW group $(80.1(13.8){\mu}m$. Conclusion: Marginal fitness of LW group showed excellent rather than RP group. However marginal fitness of 3 unit FDPs fabricated by RP method did not get out of clinical allowance value range significantly to allow clinical application.

• Atmosphere
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• v.25 no.3
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• pp.529-541
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• 2015

Korea Institute of Atmospheric Prediction System (KIAPS) has been developing a global numerial prediction model and data assimilation system. We has implemented LETKF (Local Ensemble Transform Kalman Filter, Hunt et al., 2007) data assimilation system to NCAR CAM-SE (National Center for Atmospheric Research Community Atmosphere Model with Spectral Element dynamical core, Dennis et al., 2012) that has cubed-sphere grid, known as the same grid system of KIAPS Integrated Model (KIM) now developing. In this study, we have assimilated Global Positioning System Radio Occultation (GPS-RO) bending angle measurements in addition to conventional data within ensemble-based data assimilation system. Before assimilating bending angle data, we performed a vertical unit conversion. The information of vertical localization for GPS-RO data is given by the unit of meter, but the vertical localization method in the LETKF system is based on pressure unit. Therefore, with a clever conversion of the vertical information, we have conducted experiments to search for the best vertical localization scale on GPS-RO data under the Observing System Simulation Experiments (OSSEs). As a result, we found the optimal setting of vertical localization for the GPS-RO bending angle data assimilation. We plan to apply the selected localization strategy to the LETKF system implemented to KIM which is expected to give better analysis of GPS-RO data assimilation due to much higher model top.

• International Journal of CAD/CAM
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• v.6 no.1
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• pp.9-17
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• 2006

Performing inspections for Hull Condition Monitoring and Assessment as stipulated in IACS unified requirements and IMO's Condition Assessment Scheme (CAS) IMO Resolution MEPC.94(46), 2001, Condition Assessment Scheme, IMO Resolution MEPC.111(50), 2003, Amendments to regulation 13G, addition of new regulation 13H involves a huge amount of measurement data to be collected, processed, analysed and maintained. Information to be recorded consists of thickness measurements and visual assessment of coating and cracks. The amount of data and increasing requirements with respect to condition assessment demand efficient computer support. Currently, due to the lack of standardization for this kind of data, the thickness measurements are recorded manually on ship drawings or tables. In this form, handling of the measurements is tedious and error-prone and assessment is difficult. Data reporting and analysis takes a long time, leading to some repairs being performed only at the next docking of the ship or making an additional docking necessary. The recently started ED funded project CAS addresses this topic and develops-as a first step-a data model for Hull Condition Monitoring and Assessment (HCMA) based on XML-technology. The model includes simple geometry representation to facilitate a graphically supported data collection as well as an easy visualisation of the measurement results. In order to ensure compatibility with the current way of working, the content of the data model is strictly confined to the requirements of the measurement process. Appropriate data interfaces to classification software will enable rapid assessment by the classification societies, thus improving the process in terms of time and cost savings. In particular, decision-making can be done while the ship is still in the dock for maintenance.

• Korean Journal of Head & Neck Oncology
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• v.12 no.2
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• pp.181-187
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• 1996

We have characterized 4 human squamous carcinoma cell lines established from the larynx and hypopharynx area. All the cell lines were cultured in RPMI-1640 medium. During the growth they showed monolayer adherence pattern in culture flask. They showed tonofilament on transmission electromicroscopy which is characteristic of squamous cell epithelium. DNA finger-printing using Hinf-l proved them to be originated from different beings. Flow cytometric analysis revealed them to show aneuploidy. Immunohistochemical staining for cytokeratin was done using CK1, CK8.13, CK19 and CAM5.2 antibody, and produced various patterns of positivity. All the cell lines showed varying degrees of tumorigenecity in athymic nude mice when injected subcutaneously, but only heterotransplanted SNU-1041 cell line showed continuous tumor growth. Histopathologic findings of the heterotransplanted tumors were identical to those of the original tumors of patients. This study suggests that establishment of many different squamous cell lines might bestow great capability in researches of the head and neck cancer.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.4
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• pp.682-691
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• 2017

In this paper, we propose the fusion design methodology of both pedestrian detection and object tracking system realized with the aid of HOG-PCA based RBFNN pattern classifier. The proposed system includes detection and tracking parts. In the detection part, HOG features are extracted from input images for pedestrian detection. Dimension reduction is also dealt with in order to improve detection performance as well as processing speed by using PCA which is known as a typical dimension reduction method. The reduced features can be used as the input of the FCM-based RBFNNs pattern classifier to carry out the pedestrian detection. FCM-based RBFNNs pattern classifier consists of condition, conclusion, and inference parts. FCM clustering algorithm is used as the activation function of hidden layer. In the conclusion part of network, polynomial functions such as constant, linear, quadratic and modified quadratic are regarded as connection weights and their coefficients of polynomial function are estimated by LSE-based learning. In the tracking part, object tracking algorithms such as mean shift(MS) and cam shift(CS) leads to trace one of the pedestrian candidates nominated in the detection part. Finally, INRIA person database is used in order to evaluate the performance of the pedestrian detection of the proposed system while MIT pedestrian video as well as indoor and outdoor videos obtained from IC&CI laboratory in Suwon University are exploited to evaluate the performance of tracking.

• Journal of Technologic Dentistry
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• v.40 no.2
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• pp.63-69
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• 2018

Purpose: The purpose of this study is to investigate the non-precious metal core materials used in the dental laboratory to fabricate the implant superstructure by CAD / CAM method. And to observe and compare the morphology and distribution of the osteoblasts in relation to implant osseointegration. Methods: In this study, the mandibular right first molar tooth model was selected as an international standard to produce a single core. Using this model, the impression was made with the silicone rubber, the tooth model was scanned, and a single core was designed and 5-axis milling was performed. The materials used were Cobalt-Chromium and Nickel-Chromium, and the cores for dental implant top structures were fabricated according to the procedures of the dental labs. After the fabrication, the marginal area of the core was separated and cell culture experiment was performed. The osteoblast cells used MC3T3-E1, which is currently widely used. For morphological analysis of osteoblasts, cells were posttreated and observed using CLSM (Confocal Laser Scanning Microscope) and compared. Results: The cell adhesion behavior of the specimen surface measured by CLSM was uniformly distributed in specimen A (Cobalt-Chromium) than in specimen B (Nickel-Chromium). The distribution and changes of the cells were different in the two specimens. Conclusion : It is possible to confirm that specimen A (Cobalt-Chromium) is suitable for the living body through adhesion and proliferation of osteoblasts related to implant osseointegration in the non-precious metal superstructure used after implantation. It is considered that it is preferable to use Co-Cr when fabricating the superstructure.

• Journal of Haehwa Medicine
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• v.8 no.1
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• pp.403-424
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• 1999

To evaluate the antitumor activity, antimetastatic and radioprotective effects of Kamisasammaekmundongtang(KSMT), studies were done experimentally. The results were obtained as follows: 1. In cytotoxicity against P388, A549 and B16-F10, KSMT was not showed satisfiable cytotoxicity as compared with control. 2. In Inhibitory effect on activity of DNA topoisomerase I, KSMT has strong inhibitory effect. 3. The inhibitory effect on adhesion of A549 to complex extracellular matrix was significantly increased at 0.5mg/ml, 1mg/ml of KSMT. 4. The T/C% was 122 in KSMT treated group in S-180 bearing ICR mice. 5. In antiangiogenetic effect on CAM assay, inhibitory rate was 33% in KSMT treated group. 6. In pulmonary colonization assay, a number of colonies in the lungs were decreased significantly in KSMT treated group as compared with control group. 7. By FACS analysis of splenic leukocyte after exposure to radiation by linear accelerator, T-helper cell, B cell and macrophage in KSMT treated group were significantly increased while splenocytes were decreased in control group. 8. In histological changes of jejunum of $Bald{\setminus}C$ mice after exposure to radiation by linear accelerator, exclusion and fusion of villi were decreased as compared with control group. But in duodenum and ileum, exclusion and fusion of villi were not decreased as compared with control group. 9. WBC, PLT were increased in KSMT treated group as compared with control group after exposure to radiation by linear accelerator, but the increasing effect was not significant. Above results suggest that KSMT may be useful in prevention of cancer metastasis and protection from damage by radiotherapy. But the further study of KSMT would be demanded.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.198-203
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• 2013

PURPOSE. The purpose of this study was to investigate the effect of resin cements and primer on the retentive force of zirconia copings bonded to zirconia abutments with insufficient retention. MATERIALS AND METHODS. Zirconia blocks (Lava, 3M ESPE, St. Paul, MN, USA) were obtained and forty sets of zirconia abutments and copings were fabricated using CAD/CAM technology. They were grouped into 4 categories as follows, depending on the types of resin cements used, and whether the primer is applied or not:Panavia F2.0 (P), Panavia F2.0 using Primer (PRIME Plus, Bisco Inc, Schaumburg, IL, USA) (PZ), Superbond C&B (S), and Superbond C&B using Primer (SZ). For each of the groups, the cementation was conducted. The specimens were kept in sterilized water ($37^{\circ}C$) for 24 hours. Retentive forces were tested and measured, and a statistical analysis was carried out. The nature of failure was recorded. RESULTS. The means and standard deviations of retentive force in Newton for each group were $265.15{\pm}35.04$ N (P), $318.21{\pm}22.24$ N (PZ), $445.13{\pm}78.54$ N (S) and $508.21{\pm}79.48$ N (SZ). Superbond C&B groups (S & SZ) showed significantly higher retentive force than Panavia F2.0 groups (P & PZ). In Panavia F2.0 groups, the use of primer was found to contribute to the increase of retentive force. On the other hand, in Superbond C&B groups, the use of primer did not influence the retention forces. Adhesive failure was observed in all groups. CONCLUSION. This study suggests that cementation of the zirconia abutments and zirconia copings with Superbond C&B have a higher retentive force than Panavia F2.0. When using Panavia F2.0, the use of primer increases the retentive force.