• Geomechanics and Engineering
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• v.21 no.2
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• pp.133-142
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• 2020

Submerged floating tunnel (SFT) is a type of tunnel which causes the tunnel segments to float in the water. When the SFTs are connected to the ground, the connection between the SFT and the subsea bored tunnel is fragile due to the difference in behavioral characteristics between the two types of tunnels. Therefore, special design and construction methods are needed to ensure the stability of the area around the connection. However, since previous research on the stability of the connection site has not been undertaken enough, the basic step necessitates the evaluation of ground behavior at the shore connection. In this study, the numerical analysis targeting the shore connection between the subsea bored tunnel and the SFT was simulated. The strain concentration at the shore connection was analyzed by numerical simulation and the effects of several factors were examined. The results showed the instability in the ground close to the shore connection due to the imbalance in the behavior of the two types of tunnels; the location of the strain concentration varies with different environmental and structural conditions. It is expected that the results from this study can be utilized in future studies to determine weak points in the shore connection between the submerged floating tunnel and the subsea bored tunnel, and devise methods to mitigate the risks.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.4
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• pp.394-400
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• 2007

The properties and weldability of lap joints by PFSW with 1050 Al sheet was investigated according to tool shape. dimension and welding condition. Tensile shear test was carried out for lap jointed specimen, and the hardness in the joint regions was examined. Moreover interfacial joining length, metallograph and failure location of the lap-jointed cross section were discussed. Two tool types were a simple cylindrical type and a notched cylindrical type. Under joining conditions such as plunging depth of 2.2mm. rotating speed of 1600rpm and dwelling time of 3s, the tensile shear strength of lap-jointed specimen by the notched type tool was superior to that by simple cylindrical type tool. The maximum tensile shear load of lap jointed specimen was 5807N. Optimal dimensions of the notched type tool were as follows : diameters of the shoulder and pin were $18{\phi}mm$ and $10{\phi}mm$, and pin length was 2.2mm.

• Korean Journal of Computational Design and Engineering
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• v.14 no.5
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• pp.291-296
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• 2009

This paper presents a post-processing algorithm for 5-axis machines with three rotary axes (3R-2L type). 5-axis machining needs the postprocessor for converting cutter location (CL) data to machine control (NC) data. The existing methods for post-processing use inverse kinematics equations from for-ward kinematics. However in case of 5-axis machines with three rotary axes, the inverse kinematics equations are not induced directly since the forward kinematics equations are non-linear. In order to get the joint values from the forward kinematics equations, previous algorithms use numerical method for the post-processing, which needs searching algorithms with computation time and may result in fail. This paper proposes a geometric method for the post-processing of 3 rotary type 5-axis machines. Our algorithm has three advantages: first, it does not need establishing forward kinematics equations. Second, it is reliable method that eliminates any numerical methods for the inverse kinematics, resulting in the exact solution. Finally, the proposed algorithm can also be applied to 2R-3L type of 5-axis machines.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.63-70
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• 2002

In tunnel construction, the information on the rock quality and the location of fault or fracture are crucial for economical design of support pattern and for safe construction of the tunnel. The grade of rock is commonly estimated through the observation with the naked eye of recovered cores in drilling or from physical parameters obtained by their laboratory test. Since drilling cost is quite expensive and terrains of planned sites for tunnel construction are rough in many cases, however, only limited information could be provided by core drilling Electrical resistivity and EM surveys may be a clue to get over this difficulty. Thus we have investigated electrical resistivity and EM field data providing regional Information of the rock Quality and delineating fault and fracture over a rough terrain. In this paper, we present some case histories using electrical resistivity and EM survey for the site investigation of tunnel construction. Through electrical resistivity and EM survey, the range and depth of coal seam was clearly estimated, cavities were detected in limestone area, and weak zones such as joint, fault and fracture have been delineated.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.2
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• pp.155-160
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• 2006

Giant cell-rich osteosarcoma is a rare tumor that is hard to distinguish from giant cell tumors of bone. The location and radiographic aspect of these tumors can be identical. The histologic differentiation between a giant cell-rich osteosarcoma and a giant cell tumor can be difficult. Due to the different prognosis and treatment strategies of these tumors it is essential to make the right diagnosis at presentation. This article reports a case of a giant cell-rich osteosarcoma of the proximal tibia that initially was diagnosed histologically as a giant cell tumor by needle biopsy.

• International journal of advanced smart convergence
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• v.10 no.3
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• pp.198-206
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• 2021

Based on the results of the survey and analysis of this study, we suggested a plan to activate the use of Capital Area Public Charnel Facilities as follows. First, the elderly population in Korea increased from 11.9% in 2013 to 16.4% in 2020, and the number of deaths also increased from 266,257 in 2013 to 305,127 in 2020. The supply of Public Charnel Facilities should be expanded, reflecting the cremation demand in the future and condition for the supply and increasing demand of Public Charnel Facilities after cremation, due to an increase of 14.6%. Second, it is urgent to expand the supply because the available period of using Capital Area Public Charnel Facilities is a short period of at least one year up to five years. However, as it is difficult to build Public Charnel Facilities due to location conflicts with local residents, joint construction plans between local governments should be promoted along with renting Private Charnel Facilities. Third, the enshrinement number ratio of the Public Charnel Facilities to the total cremation number of Capital Area Public Cremation Facilities is 16.3%, which is low. Therefore, when building Public Charnel Facilities, improvement plans for the use of public funeral facilities, such as modernization and promotion of facility level, quality improvement of service level, and creation of a pleasant environment, should be actively promoted.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1571-1584
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• 2023

In this study, a numerical analysis was performed as part of an international joint research project to reproduce a real cable tray fire that occurred in the heater bay area of the turbine building of a nuclear power plant. A sensitivity analysis was performed on various input parameters to derive results consistent with the sprinkler activation time obtained from the fire event analysis. For all sensitive parameters, the normalized sprinkler activation time correlated well with the power function of the normalized sprinkler height. A correlation equation was developed to identify the sprinkler activation time at any location when determining the slope or fire growth rate under the conditions assuming a linear or t-squared heat release rate (HRR) time curve. Various cable fire growth assumptions were used to determine which assumption was better to provide the prediction coincident with the information given from the fire event analysis in terms of the sprinkler activation time and total energy generated from cables damaged by fire. In the comprehensive analysis of all the sensitive parameters, the standard deviation of the input parameters increased as the sprinkler height decreased. Within the range of the sensitivity parameter values given in this study, when considering all sprinkler heights, the standard deviation of the cable model change was the largest and that of the overhang position change was the smallest.

• Journal of the Korean Society of Radiology
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• v.83 no.5
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• pp.1141-1146
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• 2022

Extraskeletal osteochondroma, a variant of chondroma, typically arises in the para-articular location of hands and feet. It is a rare disease and is particularly uncommon when joint components are not involved or localized away from joints. Herein, we report a case of extraskeletal osteochondroma in the posterior neck of a 66-year-old female. The characteristic radiologic finding of our case is presented, along with the typical findings of the disease and review of related literature reports.

• Journal of Korean Foot and Ankle Society
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• v.28 no.1
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• pp.31-35
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• 2024

Osteochondromas are benign bone tumors typically found in the metaphyseal region of long bones. These tumors are often asymptomatic and detected incidentally. However, their occurrence in atypical sites such as the talus can pose significant diagnostic and treatment challenges. This report describes a rare case of osteochondroma of the medial tubercle of the talus, which is an unprecedented location based on a review of relevant literature. A 28-year-old male presented with worsening medial ankle pain and limping. Imaging revealed a lesion consistent with osteochondroma contributing to medial ankle impingement syndrome. Uniquely, this case also featured a coinciding gout attack in the ankle joint. Surgical removal of the lesion resulted in significant symptom relief and functional improvement. This case underscores the need to consider rare diagnoses, such as talar osteochondroma, when presented with persistent medial ankle pain and highlights the potential presence of concurrent conditions, such as gout.

• Korean Journal of Acupuncture
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• v.23 no.4
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• pp.27-47
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• 2006

Objectives : The aim of this study was to analyze how to treat various symptoms through the combination of Yoelgyoel $(LU_7)$ and Johae $(KI_6)$, according to reviewing the contents and data since Ling Shu (靈樞經) to recent literatures including thirty-five medical books. Methods : It was arranged and considered that the location, needling, and symptoms of each acupoint were described in various literatures before the publication of Chim Kyung Ji Nam (鍼經指南). Through various literature since the Publication of Chim Kyung Ji Nam, it was examined how to be recognized and be referred about Yoelgyoel $(LU_7)$ and Johae $(KI_6)$. Results and Conclusions : The location of Yoelgyoel is the superior 1.5cun at wrist joint striation, medial of extensor carpi radialis longus; the location of Johae is the depression part under foot medial condyle. Yoelgyoel is often used for respiratory organ disease, urinary organ disease, neuopsychiatory disease, musculoskeletal system disease; Johae is often used for urinary organ disease, circulatory organ disease. At Chim Kyung Ji Nam, Yoelgyoel is often used for thoraco-abdominal Pain, gynecological disease, digestive organ disease; Johae is often used for abdominal pain, gynecological disease, digestive organ disease. Therefore, these points are used together for general internal disease. As well, these are not directly continuous with Previous literatures from Chim Kyung Ji Nam. The combination of Yoelgyoel and Johae have been developed to the three categories as follows; it is quoted from as it is; it is reconstructed in the form of song; it has new symptoms enlarged. Consequently, the combination of Yoelgyoel and Johae was not bind to the rule of Up-Bottom harmony (上下配合), but asserted for the rule of Ju-Eng harmony (主應配合), which add specific acupoints to e combination of Yolgyol and Chohae as the complication of the symptoms.