• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.9
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• pp.47-53
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• 2011

The signal transmission properties of the connector such as insertion loss and return loss are investigated using analysis procedure of S-parameter simulation, equivalent model extraction, and characteristic impedance calculation. S-parameter simulation is performed by connector's modeling and solving based on 3-dimensional finite element method. The connector's equivalent model of ${\pi}$ type is are proposed and extracted with an optimization process of circuit analysis simulator. The characteristic impedance of the connector is calculated with results of circuit analysis simulation and S-parameter data. According to the connector's characteristic impedance, it's revised design is carried out. In this work, the connector's effective contact area is increased and its body is applied as a high dielectric material in order to increase its capacitance and then obtain impedance matching. Therefore, return loss of the connector is improved by approximately 10 dB due to its design revision.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.12
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• pp.1968-1979
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• 2010

New technology that includes 3D body scanning, digital virtual human, and digital virtual garments has had a significant impact on the current apparel industry. Virtual simulation technology enables the visualization of a 3D virtual garment on a virtual avatar so that consumers can try on garments with their virtual avatars before purchasing. However, the manual virtual avatar provided for online apparel shopping currently has revealed limitations on the different body sizes and shapes of customers. This study analyzes the process of designing the automatic virtual avatar and the manual virtual avatar using OptiTex software; in addition, the study compares the practicality of the automatic virtual avatar with that of the manual virtual avatar. Data was examined by evaluating how much each virtual avatar is similar to the real body and how well it matched the needs of the current apparel industry. In the study, Avatar 1 was automatically created from three-dimensional body scan data and Avatar 2 was manually created from body measurements. The virtual avatar images laid over a real body image and the results were evaluated by comparing the simulated sizes of virtual avatars with those of a real body. Consequently, Avatar 1 was evaluated as more similar to the real body than Avatar 2 in all five body shapes. This study illustrates that an automatic virtual avatar might solve the fit problem that is the most common reason for a high return rate for online shopping. The results show that future virtual simulation technology needs to be improved for the practicality of the virtual avatars.

• Archives of Craniofacial Surgery
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• v.20 no.6
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• pp.361-369
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• 2019

Background: Trauma is one of the most common causes of enophthalmos, and post-traumatic enophthalmos primarily results from an increased volume of the bony orbit. We achieved good long-term results by simultaneously using an anatomical absorbable implant and iliac bone graft to correct post-traumatic enophthalmos. Methods: From January 2012 to December 2016, we performed operations on seven patients with post-traumatic enophthalmos. In all seven cases, reduction surgery for the initial trauma was performed at our hospital. Hertel exophthalmometry, clinical photography, three-dimensional computed tomography (3D-CT), and orbital volume measurements using software to calculate the specific volume captured on 3D-CT (ITK-SNAP, Insight Toolkit-SNAP) were performed preoperatively and postoperatively. Results: Patients were evaluated based on exophthalmometry, clinical photographs, 3D-CT, and orbital volume measured by the ITK-SNAP program at 5 days and 1 year postoperatively, and all factors improved significantly compared with the preoperative baseline. Complications such as hematoma or extraocular muscle limitation were absent, and the corrected orbital volume was well maintained at the 1-year follow-up visit. Conclusion: We present a method to correct enophthalmos by reconstructing the orbital wall using an anatomical absorbable implant and a simultaneous autologous iliac bone graft. All cases showed satisfactory results for enophthalmos correction. We suggest this method as a good option for the correction of post-traumatic enophthalmos.

• Steel and Composite Structures
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• v.34 no.6
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• pp.853-862
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• 2020

In recent years, due to the many advantages cable-stayed bridges have often constructed in medium and long span. These advantages can be listed as an aesthetically pleasing appearance, economic and easy construction, etc. The main structural elements of cable-stayed bridges are listed as deck, pylon, cables and foundation. Perhaps one of the most vital and expensive of these structural elements is stay-cables. Stay-cables ensure the allowable displacement and distribution of bending moments along the bridge deck with prestressing force. Therefore the optimum design of the stay-cables and prestressing force are very important in achieving the performance expected from the cable-stayed bridges. This paper aims to obtain the stay-cables size and prestressing force optimization of the cable-stayed bridge. For this purpose, single pylon and fan type cable configuration Manavgat Cable-Stayed Bridge was selected as an example. The three dimensional (3D) finite element model (FEM) of the bridge was created with SAP2000. Analysis of the 3D FEM of the bridge was conducted under the different combined effects of the self-weight of the structural element, prestressing force of stay-cable and live load. Stay-cable stress and deck displacement were taken into account as constraints for the optimization problem. To optimize this existing bridge a metaheuristic algorithm named Jaya was used in the optimization process. 3D FEM of the selected bridge was repeatedly analyzed by using Open Applicable Programming Interface (OAPI) properties of SAP2000. To carry out the optimization process the developed program which integrates the Jaya algorithm and the required codes for calling SAP2000 is coded in MATLAB. At the end of the study, the total weight of the stay-cables was reduced more than 40% according to existing stay cables under loads taken into account.

• Progress in Medical Physics
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• v.16 no.1
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• pp.47-51
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• 2005

We report a case of an accidental extravasation of contrast material. A large-volume extravasation occurred in an adult during spiral contrast-enhanced CT. The amount of contrast material extravasated was 47 ml. The patient had a swelling of the dorsum right hand. The extravasation injury site was determined by CT scanning. The extavasation case was examined using five separate display techniques: axial, multi planar reformation (MPR), maximum intensity projection (MIP), volume rendering, and shaded-surfaced display (SSD). This paper introduces extravasation with the CT and the three-dimensional appearance.

• Korean Journal of Optics and Photonics
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• v.25 no.1
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• pp.21-28
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• 2014

In this paper a Super Multi-view display method using a pinhole array with full parallax was proposed. The proposed method was simulated and its parameters analyzed. Also, the distribution and irradiance of light through each pinhole on the retina receiver, according to the change of crystalline lens focal length, were found by simulation. As a result, an image free of blurring was obtained while the crystalline lens focused on the depth plane of the three-dimensional image created by the imaging lens.

• Radiation Oncology Journal
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• v.38 no.1
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• pp.11-17
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• 2020

Purpose: Definitive radiotherapy remains a primary treatment option for early stage glottic cancer. Intensity-modulated radiation therapy (IMRT) has emerged as the standard treatment technique for advanced head and neck cancers, whereas three-dimensional conformal radiotherapy (3D-CRT) has remained standard for early glottic cancers. We used the National Cancer Database (NCDB) to identify predictors of IMRT use and effect on outcome in these patients. Materials and Methods: We queried the NCDB from 2004-2015 for squamous cell carcinoma of the glottic larynx staged Tis-T2N0 treated with radiation alone. Logistic regression was used to identify predictors of IMRT. Cox regression was used to identify factors predictive of overall survival. Propensity matching was conducted to account for indication bias. Results: We identified 15,627 patients, of which 11% received IMRT. IMRT use rose from 2% in 2004 to 16% in 2015. Predictors of IMRT include: increased comorbidity, T2 stage, urban location, chemotherapy, treatment at an academic center, and later treatment year. Predictors of improved survival were female gender, higher income, lower stage, no chemotherapy, academic facility, and more remote year. There was no difference in survival between 3D-CRT and IMRT across all stages. Conclusions: The rate of IMRT use for early stage glottic laryngeal cancer has increased over time. There was no difference in outcome in patients receiving IMRT versus 3D-CRT across the cohort.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.72.1-72.1
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• 2014

In this study, we extrapolate a nonlinear force-free field (NLFFF) from an observed photospheric magnetic field to understand the three-dimensional (3D) coronal magnetic field producing a huge solar flare. The purpose of this study is to develop a NLFFF extrapolation code based on the so-called MHD relaxation method and check how accurately our model reconstructs a coronal field. Furthermore, we apply it to the photospheric magnetic field obtained by Helioseismic and Magnetic Imager (HMI) on board Solar Dynamics Observatory (SDO) to reconstruct a 3D magnetic structure. We first investigate factors in controlling the accuracy of our NLFFF code by using a semi-analytical solution obtained by Low & Lou (1990). To extend a work done by Inoue et al. (2014), we apply various boundary conditions at the side and top boundaries in order to make our solution close to a realistic solution. As a consequence, our solution has a good accuracy when three components of a reference field are all fixed at the boundaries. Furthermore, it is also found that our solution is well matched to the Low & Lou solution in the central area of a simulation domain when the three components of a potential field are fixed at side and top boundaries (this approach is close to a realistic solution). Finally, we present the 3D coronal magnetic field producing an X 1.5-class flare in the active region 11166 through the extrapolation from SDO/HMI.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.11
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• pp.1077-1083
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• 2004

This study is to systematically analyze the effect of various kinds of design factors on the performance of stratified thermal storage tank. Taguchi method, known as a very reasonable tool in the parametric study, is employed in the present work. Three dimensional unsteady numerical experiment is conducted for 4 design parameters of stratified thermal storage tank: inlet Reynolds number, Froude number, diffuser size d with 3 levels (Re=400, 800, 1200, Fr=0.5, 1.0, 2.0 and d=150 mm, 200mm, 300 mm) and diffuser shape with 2 levels. Orthogonal array $L_{18}(2{\times}3^7)$ is adopted for the analysis of variance. The result gives quantitative estimation of the various design parameters affecting the performance and helps to select the main factors for the optimum design of stratified thermal storage tank. Reynolds number is found to be the most dominant parameter and the diffuser shape plays significant role on the performance of stratified thermal storage tank. Based on this finding, the prior questions on the contribution of the diffuser shape proposed by the authors become clear. The optimum condition for the performance is a set of d=300mm, Re=800, and radial regulated plate diffuser. Conformation test shows the repeatability in the analysis and $1.3\%$ difference between the estimated thermocline thickness and that of numerical result.

• Clinics in Orthopedic Surgery
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• v.10 no.4
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• pp.484-490
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• 2018

Background: The use of three-dimensional multi-segment foot models (3D MFMs) is increasing since they have superior ability to illustrate the effect of foot and ankle pathologies on intersegmental motion of the foot compared to single-segment foot model gait analysis. However, validation of the repeatability of the 3D MFMs is important for their clinical use. Although many MFMs have been validated in normal adults, research on MFM repeatability in children is lacking. The purpose of this study is to validate the intrasession, intersession, and interrater repeatability of an MFM with a 15-marker set (DuPont foot model) in healthy children. Methods: The study included 20 feet of 20 healthy children (10 boys and 10 girls). We divided the participants into two groups of 10 each. One group was tested by the same operator in each test (intersession analysis), while the other group was tested by a different operator in each test (interrater analysis). The multiple correlation coefficient (CMC) and intraclass correlation coefficient (ICC) were calculated to assess repeatability. The difference between the two sessions of each group was assessed at each time point of gait cycle. Results: The intrasession CMC and ICC values of all parameters showed excellent or very good repeatability. The intersession CMC of many parameters showed good or better repeatability. Interrater CMC and ICC values were generally lower for all parameters than intrasession and intersession. The mean gaps of all parameters were generally similar to those of the previous study. Conclusions: We demonstrated that 3D MFM using a 15-marker set had high intrasession, intersession, and interrater repeatability in the assessment of foot motion in healthy children but recommend some caution in interpreting the hindfoot parameters.