• Progress in Superconductivity and Cryogenics
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• v.15 no.3
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• pp.40-48
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• 2013

Cryoablation device is a surgical instrument to produce the cooling effect to destroy detrimental biological tissue by utilizing low temperature around 110 K. Usually, this device has the concentrated cooling region, so that it is suitable for concentrated and thick target. Accordingly, it is hard to apply this device for the target which is distributed and thin target. In this study, the design procedure of a closed-loop cryoablation device with multiple J-T expansion part is developed for the treatment of incompetent of great saphenous vein. The developed cyoablation device is designed with the analysis of 1-dimensional (1-D) bio-heat equation. The energy balance is considered to determine the minimum mass flow rate of refrigerant for consecutive flow boiling to develop the uniform cooling temperature. Azeotropic mixed refrigerant R410A and zeotropic mixed refrigerant (MR) of R22 ($CHClF_2$) and R23 ($CHF_3$) are utilized as operating fluids of the developed cryoablation device to form the sufficient temperature and to verify the quality of the inside of cryoablation probe. The experimental results of R410A and the zeotropic MR show the temperature non-uniformity over the range are $244.8K{\pm}2.7K$ and $239.8K{\pm}4.7K$ respectively. The experimental results demonstrate that the probe experiences the consecutive flow boiling over the target range of 200 mm.

• Journal of the Korea Computer Graphics Society
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• v.19 no.2
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• pp.1-8
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• 2013

Captured human motion data has been widely utilized for understanding the mechanism of human motion and synthesizing the animation of virtual characters. Searching for desired motions from given motion data is an important prerequisite of analyzing and editing those selected motions. This paper presents a new method of content-based motion retrieval without the need of additional metadata such as keywords. While existing search methods have focused on skeletal configurations of body pose or planar trajectories of locomotion, our method receives a three-dimensional trajectory as its input query and retrieves a set of motion intervals in which the trajectories of body parts such as hands, foods, and pelvis are similar to the input trajectory. In order to allow the user to intuitively sketch spatial trajectories, we used the Leap Motion controller that can precisely trace finger movements as the input device for our experiments. We have evaluated the effectiveness of our approach by conducting a user study in which the users search for dozens of pre-selected motions from baseketball motion data including a variety of moves such as dribbling and shooting.

• Journal of Advanced Research in Ocean Engineering
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• v.2 no.3
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• pp.150-157
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• 2016

When blocks are supported on a dock, huge reaction forces concentrated at the supports cause structural damage owing to local stress concentrations. Thus, the supports should be arranged to avoid local failure from the reaction forces by redistributing those forces. Docking analyses to determine the proper blocks and their support arrangements are introduced so that the local stresses are minimized to warrant the safety of the docking supports. Local stresses enforced by the support arrangement should be evaluated by finite element analysis (FEA). However, it is difficult to consider an accurate 3D geometry of the blocks in the finite element model because the structural design information is too complicated to determine within several days using the FEA model. This paper presents a simplified FE model to evaluate the safety of the arrangement of supports using a simplified grillage element. The grillage element can be efficiently used to obrain the reaction forces in docking analysis becasuse the reaction forces at the supports are enough to assess the safety of block. Since a simplified grillage model of the entire ship cannot accurately calculate the local stresses, an optimized modeling method based on the grillage element was introduced. The local reaction forces obtained by the proposed approach and three-dimensional FEA were discussed for typical types of ships. It is shown that the reaction forces obtained by the present grillage model are in reasonably good agreement with the FEA model.

• Archives of Craniofacial Surgery
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• v.17 no.3
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• pp.162-164
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• 2016

Stafne bone cavity is a rare mandibular defect that was first reported by Edward C. Stafne in 1942. It commonly presents with a well-demarcated, asymptomatic, unilateral radiolucency that indicates lingual invagination of the cortical bone. A 52-year-old female patient who with nasal bone fracture, visited the hospital. During facial bone computed tomography (CT) for facial area evaluation, a well-shaped cystic lesion was accidentally detected on the right side of the mandible. Compared to the left side, no swelling or deformity was observed in the right side of the oral lesion, and no signs of deformity caused by mucosal inflammation. 3D CT scans, and mandible series x-rays were performed, which showed a well-ossified radiolucent oval lesion. Axial CT image revealed a cortical defect containing soft tissue lesion, which has similar density as the submandibular gland on the lingual surface of the mandible. The fact that Stafne cavity is completely surrounded by the bone is the evidence to support the hypothesis that embryonic salivary gland is entrapped by the bone. In most cases, Stafne bone cavity does not require surgical treatment. We believe that the mechanical pressure from the salivary gland could have caused the defect.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.245-259
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• 2003

This paper deals with an Umbrealla Arch Reinforcement Method (UARM) in tunnelling. It is known that the mechanism of the reinforcement system is too complex to be simulated in existent finite element (FE) frameworks when considering its complex geometry of pipe arrangements and contribution of each component of the reinforcement to reinforcing effect. In this study a 3-D elastoplastic FE procedure is, therefore, proposed by introducing homogenisation technique, which is used to define mathematically elastic as well as elastoplastic characteristics of a reinforced ground material as a composite. A number of practical suggestions are addressed considering staged constructions of tunnels. For illustrative purposes, a series of parametric studies are undertaken and anisotropic characteristics of the reinforced ground as well as effects of the reinforcement on tunnel convergences are investigated. It is found that the reinforced ground material defined in homogenisation framework has its mechanical characteristics reasonably representing inherent geometrical and quantitative characteristics of each of constituents.

• Journal of Environmental Policy
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• v.6 no.1
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• pp.111-132
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• 2007

The traffic noise of Busan, the second largest city in Korea, is polluting the area. Noise map is a map that shows data on an existing or predicted noise condition in terms of a noise indicator, breaches of a limit value, the number of dwellings exposed to certain values of a noise indicator in a certain area, or on cost-benefit ratios or other economic data on mitigation methods or scenarios with Geographic Information System. With noise map, the effect of traffic noise and the efficiency of city development plan are exactly estimated. So making systematic counteroffer is possible with it. This study is aimed to the construction of basis for noise map construction method for domestic use and the area focus is Busan.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.5
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• pp.1582-1589
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• 1996

Rapid prototyping is a new prototyping technology which produces three dimensional part models directrly from CAD data and has been extensively applied to various manufacturing processes. There are many types of rapid prototyping systems due to their building principles and materials. In this work, Stereolithography Appaaratus(SLA) which is the most widely-used rapid prototyping system is introduced to achieve die/mold technology innovation. For the purpose, the prototyping technology using SLA is developed such that patterns of which shapes are quite complicated are successfully produced with high accuracy. Using these patterns, prototype die/molds are efficientrly manufactured; a turbocharger rotor, a fan and a wheel patterns, prototype die/molds are efficienterly manufactured ; a turbochager rotor, a fan and a wheel pattern are made, and the molds of the investment casting, the injection molding and the die casting are manufactured respectively. The casting products are produced using these molds and it turns out that these methods are quitre effective for manufacturing products of complicated geometry from the viewpoint of efficiency and productivity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.131-131
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• 2017

Though the Platycodon grandiflorum, has a broad range of pharmacologic properties, but the mechanisms underlying these effects remain unclear. In order to profile proteins from the nodal segment, callus, root and shoot, high throughput proteome approach was executed in the present study. Two-dimensional gels stained with CBB, a total of 84 differential expressed proteins were confirmed out of 839 protein spots using image analysis by Progenesis SameSpot software. Out of total differential expressed spots, 58 differential expressed protein spots (${\geq}2-fold$) were analyzed using MASCOT search engine according to the similarity of sequences with previously characterized proteins along with the UniProt database. Out of 58 differential expressed protein, 32 protein spots were up-regulated such as ribulose-1,5-bisphosphate carboxylase, endoplasmic oxidoreductin-1, heat stress transcription factor A3, RNA pseudourine synthase 4, cysteine proteinase, GntR family transcriptional regulator, E3 xyloglucan 6-xylosyltransferase, while 26 differential protein spots were down-regulated such as L-ascorbate oxidase precursor, late embryogenesis abundant protein D-34, putative SCO1 protein, oxygen-evolving enhancer protein 3. However, the frequency distribution of identified proteins using iProClass databases, and assignment by function based on gene ontology revealed that the identified proteins from the explants were mainly associated with the nucleic acid binding (17%), transferase activity (14%) and ion binding (12%). Taken together, the protein profile may provide insight clues for better understanding the characteristics of proteins and its metabolic activities in various explants of this essential medicinal plant P. grandiflorum.

• The Journal of Korean Academy of Prosthodontics
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• v.27 no.2
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• pp.53-78
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• 1989

This study was taken to observe the changes of the residual stress in the alloy and to measure 3 dimensional distortions of the long span ceramo-metal bridge. The materials used in this study were Pors-on 4 (Pd-Ag alloy), and Ceramco and Vita VMK 68 powders. The residual stress of the alloy was measured on the six specimens (dia. 8m/m) by the X-ray diffraction stress analyzer according to the kind of ceramic powder and different measuring stages. And, for the measurement of the distortions, fifteen specimens of the anterior 8-unit ceramo-metal brige were fabricated and subjected to the 3-D coordinate measuring machine. Variables included the 2 kinds of a ceramic powder and the presence or absence of a splint bar at the cast metal framework. The measuring stages in both were after casting, after degassing and after glazing. The following conclusions were obtained : 1. The residual stress of the alloy showed increasing tendency for the tension by the ceramic fusing, but there was not significance. 2. The tendency of the distortions in the cast metal frameworks were decrease of the width, the anterior displacement and sagging. 3. The amount of the distortions at the degassing stage were greater than that at the ceramic fusing stage. 4. The splint bar was effective to control the distortion only at ceramic fusing stage. 5. The sagging distortion in the Ceramco firing were even through all measuring stages, but in the Vita firing, pronounced at degassing stage.

• Polymer(Korea)
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• v.38 no.2
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• pp.150-155
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• 2014

Polycaprolactone (PCL) is a synthetic biodegradable polymer with excellent mechanical properties. $TiO_2$ (titanium dioxide) has a hydrophilic, high density and excellent biocompatibility. In this work, we produced three-dimensional porous scaffolds with PCL and $TiO_2$ nanoparticles using a salt-leaching method. Physical properties of the scaffolds were analyzed by FE-SEM, FTIR, TGA and compressive strength. Interestingly, the addition of $TiO_2$ nanoparticles decreased the water absorption and swelling ratio of the porous scaffolds. However, the compressive strength was increased by $TiO_2$. CCK-8 assay, which is generally used for the analysis of cell growth, shows that $TiO_2$ nanoparticles have no cytotoxicity. Taken together, we suggest that the PLC/$TiO_2$-scaffold can be used for biomedical applications.