• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.1
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• pp.17-27
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• 2019

In this paper, we study the applicability of Tuned Mass Damper(TMD) to improve seismic performance of piping system under earthquake loading. For this purpose, a mode analysis of the target pipeline is performed, and TMD installation locations are selected as important modes with relatively large mass participation ratio in each direction. In order to design the TMD at selected positions, each corresponding mode is replaced with a SDOF damped model, and accordingly the corresponding pipeline is converted into a 2-DOF system by considering the TMD as a SDOF damped model. Then, optimal design values of the TMD, which can minimize the dynamic amplification factor of the transformed 2-DOF system, are derived through GA optimization method. The proposed TMD design values are applied to the pipeline numerical model to analyze seismic performance with and without TMD installation. As a result of numerical analyses, it is confirmed that the directional acceleration responses, the maximum normal stresses and directional reaction forces of the pipeline system are reduced, quite a lot. The results of this study are expected to be used as basic information with respect to the improvement of the seismic performance of the piping system in the future.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.140-152
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• 1998

Background: Prone position improves oxygenation in patients with ARDS probably by reducing shunt Reduction of shunt in prone position is thought to be effected by lowering of the critical opening pressure (COP) of the dorsal lung because the pleural pressure becomes less positive in prone position compared to supine position. It can then be assumed that prone position would bring about greater improvement in oxygenation when PEEP applied in supine position is just beneath COP than when PEEP is above COP. Hemodynamically, prone position is expected to attenuate the lifting of cardiac fossa induced by PEEP. Based on these backgrounds, we investigated whether the effect of prone position on oxygenation differs in magnitude according to the level of PEEP applied in supine position, and whether impaired cardiac output in supine position by PEEP can be restored in prone position. Methods: In seven mongrel dogs, $PaO_2/F_1O_2$(P/F) was measured in supine position and at prone position 30 min. Cardiac output (CO), stroke volume (SV), pulse rate (PR), and pulmonary artery occlusion pressure (PAOP) were measured in supine position, at prone position 5 min, and at prone position 30 min. After ARDS was established with warmed saline lavage(P/F ratio $134{\pm}72$ mm Hg), inflection point was measured by constant flow method($6.6{\pm}1.4cm$ $H_2O$), and the above variables were measured in supine and prone positions under the application of Low PEEP($5.0{\pm}1.2cm$ $H_2O$), and Optimal PEEP($9.0{\pm}1.2cm$ $H_2O$)(2 cm $H_2O$ below and above the inflection point, respectively) consecutively. Results : P/F ratio in supine position was $195{\pm}112$ mm Hg at Low PEEP and $466{\pm}63$ mm Hg at Optimal PEEP(p=0.003). Net increase of P/F ratio at prone position 30 min, however, was far greater at Low PEEP($205{\pm}90$ mm Hg) than at Optimal PEEP($33{\pm}33$ mm Hg)(p=0.009). Compared to CO in supine position at Optimal PEEP($2.4{\pm}0.5$ L/min), CO in prone improved to $3.4{\pm}0.6$ L/min at prone position 5 min (p=0.0180) and $3.6{\pm}0.7$ L/min at prone position 30 min (p=0.0180). Improvement in CO was attributable to the increase in SV: $14{\pm}2$ ml in supine position, $20{\pm}2$ ml at prone position 5 min (p=0.0180), and $21{\pm}2$ ml at prone position 30 min (p=0.0180), but not to change in PR or PAOP. When the dogs were turned to supine position again, MAP ($92{\pm}23$ mm Hg, p=0.009), CO ($2.4{\pm}0.5$ L/min, p=0.0277) and SV ($14{\pm}1$ ml, p=0.0277) were all decreased compared to prone position 30 min. Conclusion: Prone position in a dog with saline-lavaged acute lung injury appeared to augment the effect of relatively low PEEP on oxygenation, and also attenuate the adverse hemodynamic effect of relatively high PEEP. These findings suggest that a PEEP lower than Optimal PEEP can be adopted in prone position to achieve the goal of alveolar recruitment in ARDS avoiding the hemodynamic complications of a higher PEEP at the same time.

• Archives of design research
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• v.20 no.3 s.71
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• pp.119-128
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• 2007

With the development of digital technologies, CAID became an essential part in the industrial design process. Creating photo-realistic images from a virtual scene with 3D models is one of the specialized task for CAID users. This task requires a complex interface of setting the positions and the parameters of camera and lights for optimal rendering results. However, the user interface of existing CAID tools are not simple for designers because the task is mostly accomplished in a parameter setting dialogue window. This research address this interface issues, in particular the issues related to lighting, by developing and evaluating TLS(Tangible Lighting Studio) that uses Augmented Reality and Tangible User Interface. The interface of positioning objects and setting parameters become tangible and distributed in the workspace to support more intuitive rendering task. TLS consists of markers, and physical controller, and a see-through HMD(Head Mounted Display). The user can directly control the lighting parameters in the AR workspace. In the evaluation experiment, TLS provide higher effectiveness, efficiency and user satisfaction compared to existing GUI(Graphic User Interface) method. It is expected that the application of TLS can be expanded to photography education and architecture simulation.

• Clinics in Shoulder and Elbow
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• v.3 no.2
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• pp.95-101
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• 2000

Purpose : The purpose of this study was to evaluate the efficacy of oblique coronal MR images, oblique axial images of neutral, internal rotation and external rotation positions in the diagnosis of SLAP Ⅱ lesion. Materials and Methods: MR arthrography of the glenohumeral joint was evaluated retrospectively in 16 patients(16 shoulders) who underwent arthroscopic surgery(mean age; 38 years old, Male; 13, Female; 3). Oblique coronal fat-suppressed Tl-weighted spin echo images were performed with each shoulder in the neutral position of the arm and oblique axial images were performed in neutral, internal and external rotations of the arm respectively. The preoperative findings of MR were classified as definite tear, possible tear and no tear. Arthroscopic findings were correlated with MR findings of several different position of the arm. Results: Arthroscopic surgery revealed 8 SLAP Ⅱ lesion, 2 SLAP I lesion, and 6 normal superior labrum respectively. The accuracy of diagnosis in the 8 SLAP Ⅱ lesion were high on oblique axial image in external rotation which were interpreted as 8 definite tear, to compare with oblique axial images in neutral position which were interpreted as 4 definite tear, 3 possible tear, 1 no tear. The 6 normal superior labrum lesion were interpreted as no tear in all three position. The 2 SLAP I lesion were interpreted as 1 definite tear, 1 no tear on oblique axial image in neutral position and 1 definite tear, 1 possible tear on oblique axial image in external rotation. Conclusion: This study showed that axial MR images in external rotation of the arm combined with oblique coronal images have proved to be effective to detect SLAP Ⅱ lesion, and should be considered in imaging protocol for MR arthrography of the SLAP Ⅱ lesion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.305-313
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• 2019

Recently, spatial information is being constructed actively based on the images obtained by drones. Because occlusion areas occur due to buildings as well as many obstacles, such as trees, pedestrians, and banners in the urban areas, an efficient way to resolve the problem is necessary. Instead of the traditional way, which replaces the occlusion area with other images obtained at different positions, various models based on deep learning were examined and compared. A comparison of a type of feature descriptor, HOG, to the machine learning-based SVM, deep learning-based DNN, CNN, and RNN showed that the CNN is used broadly to detect and classify objects. Until now, many studies have focused on the development and application of models so that it is impossible to select an optimal model. On the other hand, the upgrade of a deep learning-based detection and classification technique is expected because many researchers have attempted to upgrade the accuracy of the model as well as reduce the computation time. In that case, the procedures for generating spatial information will be changed to detect the occlusion area and replace it with simulated images automatically, and the efficiency of time, cost, and workforce will also be improved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.1-8
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• 2018

This paper describes new communication methods for transmitting torque commands between the vehicle controller that determines the amount of power generation in a range-extended electric vehicle and the engine controller that performs it. Generally, vehicles use CAN communication, but in this case, the hardware and software of the existing engine controller must be modified. For this reason, it is not easy to apply CAN communication to small and medium sized automotive reorganize companies. Therefore, this research presents a pin-pin communication method for applying the existing mass produced engine controller to range-extended electric vehicles. The pin-pin communication method converts the driver's demand torque control map inside an mass produced engine controller into a virtual accelerator opening position according to the target speed and target torque of the engine, and converts this to a voltage signal for the existing mass produced engine controller to recognize it. The virtual accelerator opening positions are mounted in the form of a control map in the vehicle controller through the reverse conversion process in an offline environment and are determined by the engine generating power requirements and engine optimal operating point algorithm. These algorithms and signal conversion circuits for engine torque transmission have been mounted on the vehicle controller to conduct the virtual accelerator opening position conversion process according to the engine target torque and to establish the virtual accelerator voltage signal using the signal converter.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.2
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• pp.167-174
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• 2010

In this study, the optimal position for the backrest pivot of an office chair was investigated by evaluating its performance in terms of the lumbar support and sliding distance of the back from the backrest during tilting motions. The simulation was performed using a mathematical model, which included a human body and a chair. Forty-two backrest pivot points were selected on the sagittal plane around the hip joint of a sitting model. A motion analysis study was also performed using a prototype of an office chair (A-type) with a backrest pivot located on the hip joint of a normal Korean model and a typical office chair (B-type) with its pivot located under the seat. The simulation results showed that both the lordosis angle and the slide distance of the back were minimized when the backrest pivot was positioned close to the hip joint. The experimental results showed that the slide distance and gap between the sitter's lumbar and the backrest was smaller with the A-type than the B-type. Based on the simulation and experimental results, it can be concluded that the backrest can support the sitter's lumbar area more effectively as the pivot position for reclining approaches closer to the hip joint. In this position, the sitter can maintain a comfortable and healthy sitting posture. This paper presents the methods and guidelines for designing an office chair with ergonomic considerations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.468-474
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• 2012

In this study, experimental studies were performed for the carbon nanomaterial(CNM) which is catching on as a material for eco-ship. The opposed-flow methane flame was used as a heat source for synthesis of CNM. Ferrocene was used as a catalyst for the synthesis of CNM. These major parameters were $H_2$ mixing rate and sampling positions that synthesize CNMs in opposed-flow diffusion flames. The propensities of CNMs were experimentally determined using SEM and TEM images. The experimental result showed that the amount of CNTs was increased with increasing $H_2$ concentration. It can also be found that the optimal temperature in opposed-flow methane flame for synthesis of CNT was about 1500 K.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.745-751
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• 2013

Environmental Specimen Banks (ESBs) have been established widely in the world since 1979 for monitoring long-term bio-accumulation of environmental pollutants. The ESBs perform the retrospective analysis of representative biological samples collected regularly and store them in cryogenic condition. In Korea, National Environmental Specimen Bank (NESB) was established in 2009. Since then, NESB had prepared the standard operating procedures (SOPs) for the seven kinds of specimens (Red Pine (Pinus densiflora), Common Carp (Cyprinus carpio), and etc.) for monitoring the effect of environmental pollution on the terrestrial ecosystem and river ecosystem. In 2012, NESB added Black-tailed Gull (Larus crassirostris)'s eggs to the list of the environmental specimen for monitoring marine environmental pollution. In this study, we sampled the eggs of the Black-tailed Gull on two islands (Baekryeongdo of the West Sea and Hongdo of the South Sea). Especially, we selected eggs which remained in the early stages of embryo development for certifying the consistent and stable monitoring for environmental pollutants in egg contents. However, it was not considered to classify an order of eggs per clutch in this study. It is known that the concentration variations of pollutants exist among eggs in one clutch. Therefore, it is needed to consider the positions of eggs in the laying sequences to meet the objective of bioaccumulation monitoring. We collected 30 eggs in each site but the amount may be insufficient to achieve storage target (over 2,000 g). Therefore, we need to consider an optimal sampling size.

• Journal of Christian Education in Korea
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• v.62
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• pp.101-133
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• 2020

This study is an attempt to grasp the fundamental characteristics and core structures of Bibliodrama, which has recently received a lot of attention in various fields including Christian education. Bibliodrama is a guided form of process-oriented staging of biblical texts in groups with the aim of mutually opening up the text and the biography of the participants in the implementation of holistic encounters (H. Aldebert). In the background of the birth of Bibliodrama can be found the hermeneutical efforts of the biblical scholar Walter Wink who sentenced the bankruptcy of historical criticism. He laid the biblical interpretative foundation for Bibliodrama which combines Bible and body. German theologian Gerhard Marcel Martin had a new experience of seeing the Bible through body activity during his life in New York, and based on that experience he began to work on the Bibliodrama. And the New Testament scholar Tim Schramm, who focused on the TCI (themecentered interaction) movement, found the optimal methodology to embody the interaction of biblical studies in Bibliodrama. On the other hand, Peter Pitzele, who wanted to realize the Bibliodrama in the tradition of Midrash, has developed a new type of Bibliodrama (Bibliolog) that is different from the European Bibliodrama. When we put together the positions of the pioneers of Bibliodrama, it turns out that it has three fundamental characteristics: body, interaction, and the empty space of the Bible. The body refers to the personality of learners participating in the Bibliodrama. They are not passive participants, but voluntary and active participants. Interaction is realized through the dramatic way of Bibliodrama. Bibliodrama aims for a dynamic process in which hermeneutical interaction occurs. The empty space of the Bible, which Bibliodrama pays attention to, allows us to understand why the Bible is not a fixed word but a living word that is still heard today. In order to understand the Bible as the content of education, Bibliodrama liberates the text that is fixed in a literal way and gives life by paying attention to the empty space of the Bible and reading it slowly.