• Structural Engineering and Mechanics
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• v.72 no.6
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• pp.675-687
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• 2019

As the bridges are an integral part of the transportation network, their function as one of the most important vital arteries during an earthquake is fundamental. In a design point of view, the bridges piers, and in particular the wall piers, are considered as effective structural elements in the seismic response of bridge structures due to their cantilever performance. Owing to reduced seismic load during design procedure, the response of these structural components should be ductile. This ductile behavior has a direct and decisive correlation to the development of plastic hinge region at the base of the wall pier. Several international seismic design codes and guidelines have suggested special detailing to assure ductile response in this region. In this paper, the parameters which affect the length of plastic hinge region in the reinforced concrete bridge with wall piers were examined and the sensitivity of these parameters was evaluated on the length of the plastic hinge region. Sensitivity analysis was accomplished by independently variable parameters with one standard deviation away from their means. For this aim, the Monte Carlo simulation, tornado diagram analysis, and first order second moment method were used to determine the uncertainties associated with analysis parameters. The results showed that, among the considered design variables, the aspect ratio of the pier wall (length to width ratio) and axial load level were the most important design parameters in the plastic hinge region, while the yield strength of transverse reinforcements had the least effect on determining the length of this region.

• The Korean Journal of Quaternary Research
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• v.23 no.2
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• pp.13-33
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• 2009

Mineralogical analysis with petrographic microscope and XRD was carried out to verify manufacturing technique of the tiles(9 samples) and kiln wall materials(5 samples) from the Anchang-ri history site in Wonju county. One of the results we found is such that during the tile manufacturing process fine tile fragments or wall materials might be added instead of chamottes to maintain tile pattern. Abandoned tiles or wall materials were recycled repeatedly, which may be supported by the recycled chamottes that made from iron-rich fine aggregates or disposed kiln wall materials in many samples analyzed. The tiles and wall materials are divided into 3 types, including low temperature type (below $800^{\circ}C$), intermediate temperature type ($800-930^{\circ}C$) and high temperature type ($930-1470^{\circ}C$) as a function of firing temperature which deduced by mineral assemblages identified under petrographic microscope and by XRD composition. Both Kiln A8 of Choseon Dynasty and wall material AW5 were burned at the highest temperature among the all analyzed samples.

• Journal of Chest Surgery
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• v.29 no.2
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• pp.239-243
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• 1996

Chest wall reconstruction Is difficult because of the physiological and anatomical functions of thoracic cavity where the thoracic cavity must be stabilized in order to prevent paradoxical motion, and adequate protection must be provided to the mediastinal structures. A 37-year-old male patient with full-thickness defect on the left anterior thoracic cavity due to traffic accident was treated. Emergency operation was performed for debridement and bleeding control, and on postoperative 25 days, chest wall reconstruction was performed as a second-stage operation. Left anterior chest wall was reconstructed with latissimus dorsi myocutaneous flap which had thoracodorsal arterial pedicle, and split-thickness skin grift from the left thigh was done. After chest wall reconstruction, spontaneous self-respiration was possible without ventilatory support. The pulmonary function test performed at postoperative 3 months revealed 80% of predicted values (FVC, FEV1.0). The postoperative result of chest wall reconstruction using latissimus dorsi myocutaneous flap was excellent anatomically, physiologically and aesthetically.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.1
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• pp.304-320
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• 1996

A multiple production .epsilon. equation model was developed in the low Reynolds number $\kappa$-$\varepsilon$ model with the aids of DNS data. We derived the model theoretically and avoided the use of empirical correlations as much as possible in order for the model to have generality in the prediction of complex turbulent flow. Unavoidable model constants were, however, optimized with the aids of DNS data. All the production and dissipation models in the $\varepsilon$ equation were modified with damping functions to satisfy the wall limiting behavior. A new $f_{\mu}$ function, turbulent diffusion and pressure diffusion model for the k and .epsilon. equations were also proposed to satisfy the wall limiting behavior. By, computational investigation on the plane channel flows, we found that the multiple production model for .epsilon. equation could improve the near wall turbulence behavior compared with the standard production model without the complicated empirical modification. Satisfication of the wall limiting conditions for each turbulence model term was found to be most important for the accurate prediction of near wall turbulence behaviors.

• Journal of Veterinary Clinics
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• v.41 no.1
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• pp.24-29
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• 2024

A 6-year-old spayed female French Bulldog presented with a left-sided chest wall tumor. Physical examination revealed that the tumor was firmly adhered to the chest wall. A preoperative punch biopsy of the tumor revealed a grade 2 soft tissue sarcoma (STS). On computed tomography, the tumor's dimensions were assessed as 6.5 × 5.7 × 3.5 cm, and it exhibited invasiveness near the tissue surrounding the ninth rib. The tumor size was large in comparison to the dog's chest wall area. Hence, if the traditional wide-margin resection surgery were to be performed, primary wound closure seemed impractical and could potentially result in respiratory function complications. Therefore, considering the extent of tumor invasion and grade, deep margins were established to include the removal of the eighth to tenth ribs, and a 1-cm lateral margin was designated to enable primary wound closure. To reconstruct the chest wall, polypropylene mesh was attached to the adjacent ribs and the remaining muscles were sutured and covered over the mesh. The dog exhibited a rapid recovery beginning the day after the operation. Postoperative biopsy confirmed that the tumor was a grade 2 STS, and the surgical margins were evaluated as incomplete. The owner chose to pursue follow-up observation instead of chemotherapy. In this study, the surgical approach was chosen based on the importance of functional recovery after surgery. Recent research indicates that the tumor grade is more critical for postoperative prognosis than the extent of surgical margins when removing an STS.

• Journal of Korea Water Resources Association
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• v.53 no.1
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• pp.1-13
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• 2020

The most common approach for computing engineering flow problems at high Reynolds number is still the Reynolds-averaged Navier-Stokes (RANS) computations based on turbulence models with wall functions. The recently developed generalized wall functions blending between the wall-limiting viscous and the outer logarithmic relations ensure a smooth transition of flow quantities across two regions. The performances and convergence properties of widely used turbulence models with wall functions that are applicable for turbulence kinetic energy (TKE), turbulent and specific dissipation rates, and eddy viscosity are presented through a series of near wall flow simulations. The present results show that RNG k-𝜖 model should be carefully applied with small tolerance to get the stable solution when the first grid lies in the buffer layer. The standard k-𝜖 and RNG k-𝜖 models are not sensitive to the selection of wall functions for both TKE and eddy viscosity, while the k-ω SST model should be applied together with kL-wall function for TKE and nutUB-wall functions for eddy viscosity to ensure accurate and stable boundary conditions. The applications to a backward-facing step flow at Re=155,000 reveal that the reattachment length is reasonably well predicted on appropriately refined mesh by all turbulence models, except the standard k-𝜖 model which about 13% underestimates the reattachment length regardless of the grid refinement.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.4-21
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• 2021

The purpose of this study is to examine the names and types of walls constructed in the late Joseon Dynasty in YeonggeonUigwe, a record of construction works of the Joseon Dynasty, and to examine the current status and name of walls constructed in the main hall and the Yeongnyeongjeon Hall of Jongmyo Shrine. The results of the study are as follows. First, the name of the wall can be divided into four types depending on the characteristics, including direction, location, shape, function, material, and complexity, and was used as a compound word in front of the wall. Second, some of the wall types related to the material were found to have differences in the timing of theypes of walls. Since the 18th century, the use of earthen walls has been reduced, and the use of wooden walls and paper walls are often used. Third, the walls of the Jongmyo Shrine were composed of a mud wall and a fireproof wall. A fireproof wall was installed in the main hall, including a pillar, while the Yeongnyeongjeon Hall was installed only between the pillar and the pillar. Fourth, the Gap Wall can be defined as the "wall constructed at the upper part of the chamber used in the construction of the building in Jongmyo." This study is meaningful in that it attempted to clarify the definition of a wall in the late Joseon Dynasty by examining the names and examples of walls used in the late Joseon Dynasty, focusing on walls that lacked research in familiarity.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4577-4581
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• 2016

Objective: The aim of this study was to assess thyroid function in breast cancer patients exposed to therapeutic external beam radiation. The focus was on possible progressive changes and any relationships between the incidence of primary hypothyroidism, the time required to become hypothyroid, and factors such as chemotherapy, hormonotherapy and immunotherapy. Materials and Methods: Seventy females undergoing 3D conformal and IMRT radiation therapy for breast cancers were enrolled in a non-randomized prospective study. The patients was divided into two groups: those after mastectomy or breast conserving surgery (BCS) were irradiated to a scar of the chest wall/breast and the ipsilateral supraclavicular and the axillary areas (supraclavicular radiotherapy group - SC-RT group - 32 patients) and the control group receiving adjuvant chest wall/breast RT only (BCT group - 38 patients).The total doses were 50.0 to 70 Gy in 5 to 7 weeks. The median follow-up term was 24 months (range, 1-40 months). Thyroid function was evaluated by measuring thyroid stimulating hormone (TSH), free thyroxine (fT4), and free triiodothyronine (fT3) levels. The minimum, maximum and mean thyroid gland doses for 20 Gy (V20) were calculated for all patients. Results: Statistically significant results were obtained for the SC-RT group. Two yearsa fter the end of RT the chance of an event was increased in 6% of the population (p=0.009) in the SC-RT group. In the BCT group no significance was noted. No statistically significant differences were found for V20, chemio-, immunotherapy and hormonotherapy or Ki67 values (p=0.12). No significant results were obtained for development of hypothyroidism and clinical factors (age, thyroid volume, treatment modalities). Conclusion: Radiotherapy is associated with a higher incidence of thyroid toxicity in breast cancer patients. Routine thyroid function monitoring should be recommended in such cases.

• Investigative Magnetic Resonance Imaging
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• v.21 no.1
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• pp.20-27
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• 2017

Purpose: To evaluate quantification results of single breath-hold (SBH) magnetic resonance (MR) cine imaging compared to results of conventional multiple breath-hold (MBH) technique for left ventricular (LV) function in patients with cardiac arrhythmia. Materials and Methods: MR images of patients with arrhythmia who underwent MBH and SBH cine imaging at the same time on a 1.5T MR scanner were retrospectively reviewed. Both SBH and MBH cine imaging were performed with balanced steady state free precession. SBH scans were acquired using temporal parallel acquisition technique (TPAT). Fifty patients ($65.4{\pm}12.3years$, 72% men) were included. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), myocardial mass, and LV regional wall motion were evaluated. Results: EF, myocardial mass, and regional wall motion were not significantly different between SBH and MBH acquisition techniques (all P-values > 0.05). EDV, ESV, and SV were significant difference between the two techniques. These parameters for SBH cine imaging with TPAT tended to lower than those in MBH. EF and myocardial mass of SBH cine imaging with TPAT showed good correlation with values of MBH cine imaging in Passing-Bablok regression charts and Bland-Altman plots. However, SBH imaging required significantly shorter acquisition time than MBH cine imaging ($15{\pm}7sec$ vs. $293{\pm}104sec$, P < 0.001). Conclusion: SBH cine imaging with TPAT permits shorter acquisition time with assessment results of global and regional LV function comparable to those with MBH cine imaging in patients with arrhythmia.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.5
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• pp.685-697
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• 1998

Series of recent k-.epsilon. model modification have been carried out with the aid of DNS data to include the effect of near wall. Though these methods opened new way of turbulence modelings, newly developed turbulence models of its kind had yet shortcomings in prediction for the turbulent flows with various Reynolds numbers and various geometric conditions. As a remedy for these shortcomings, a new k-.epsilon. model proposed here by improving the dissipation rate equation and the damping function for eddy viscosity model. The new dissipation rate equation was modeled based on the energy spectrum and magnitude analysis. The damping function for eddy viscosity was also formulated on the ground of distribution of dissipation rate length scales near a wall and the DNS data. The new k-.epsilon. model was applied to the fully developed turbulent flows in a channel and a pipe with a wide range of Reynolds numbers. Prediction results showed that the present model represents properly the turbulence properties in all turbulent regions over a wide range of Reynolds numbers.