• Progress in Superconductivity and Cryogenics
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• v.7 no.3
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• pp.13-16
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• 2005

Multi-stacked HTS tapes are needed to conduct large current in the power application. In this paper magnetization losses of the multi-stacked YBCO coated conductor and the BSCCO tape have been measured and compared. Magnetization losses of single tape, 2-stacked, 3-stacked and 4-stacked HTS tapes have been presented in this paper. Multi-stacked tapes have been fabricated using face-to-face type stacking method. Measurements of magnetization loss were performed under various stacked of external magnetic field to consider the anisotropic characteristics of HTS tapes. Test results show that loss density per unit volume decreased for both YBCO coated conductors and BSCCO tapes when the stacking number of tapes is increased. As the external magnetic field decreased, the ratio of decrement has risen because the full penetration magnetic field(Bp) of the multi-stacked tape is larger than that of the single tape.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.8
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• pp.922-931
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• 1992

This paper presents an efficient algorithm for converting the boundary representation of a polyhedron to its corresponding octree representation which is convenient for detecting intersection between objects. In order to determine the states of octants efficiently and quickly, our algorithm consists of three basic processes which use the bounding box, the infinite plane and the projection. In our conversion algorithm, the states of octants are determined by performing one of these three processes according to the intersecting pattern of an octant with a polyhedron, instead of by performing only a face-to-face intersection test repeatedly. In particular, states of 8 suboctants are determined completely by performing the process using only the infinite plane, when the given octant is intersected with only a patch of the polyhedron. Finally, by using a 3D display method and a volume ratio method, it is confirmed that the octree converted by out algorithm is accurate. It is also confirmed that the conversion time is reduced in our algorithm.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.90-96
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• 2021

The logistics market is continuously growing due to the development of technology and the growth of the online market. In addition, the social atmosphere that emphasizes non-face-to-face due to the pandemic situation is accelerating the growth of logistics. Delivery of goods ordered online requires delivery process through courier worker. In order for the courier worker to ship the product, the work of loading the product on the truck must be preceded. The accident caused by such delivery and loading work is increasing and it is emerging as a social problem. This study proposes a robot-based automated loading system to efficiently handle the increasing volume of courier service and to construct a more efficient and safe working environment by replacing the physical labor that was overloaded to courier workers. The proposed system replaces the loading of the courier worker and proposes the optimal loading function through the automation system.

• Current Optics and Photonics
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• v.5 no.1
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• pp.32-39
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• 2021

We propose a three-dimensional (3D) streaming system based on a lamina display that can convey field information in real-time by creating floating 3D images that can satisfy the accommodation cue. The proposed system is mainly composed of three parts, namely: a 3D vision camera unit to obtain and provide RGB and depth data in real-time, a 3D image engine unit to realize the 3D volume with a fast response time by using the RGB and depth data, and an optical floating unit to bring the implemented 3D image out of the system and consequently increase the sense of presence. Furthermore, we devise the streaming method required for implementing augmented reality (AR) images by using a multilayered image, and the proposed method for implementing AR 3D video in real-time non-face-to-face communication has been experimentally verified.

• Steel and Composite Structures
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• v.41 no.6
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• pp.821-829
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• 2021

Nonlinear dynamic response of a sandwich beam considering porous core and nano-composite face sheet on nonlinear viscoelastic foundation with temperature-variable material properties is investigated in this research. The Hamilton's principle and beam theory are used to drive the equations of motion. The nonlinear differential equations of sandwich beam respect to time are obtained to solve nonlinear differential equations by Homotopy perturbation method (HPM). The effects of various parameters such as linear and nonlinear damping coefficient, linear and nonlinear spring constant, shear constant of Pasternak type for elastic foundation, temperature variation, volume fraction of carbon nanotube, porosity distribution and porosity coefficient on nonlinear dynamic response of sandwich beam are presented. The results of this paper could be used to analysis of dynamic modeling for a flexible structure in many industries such as automobiles, Shipbuilding, aircrafts and spacecraft with solar easured at current time step and the velocity and displacement were estimated through linear integration.

• Journal of Dental Anesthesia and Pain Medicine
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• v.22 no.6
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• pp.451-455
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• 2022

Glycogen storage disease (GSD) is a group of inherited disorders, which result in the deficiency of enzymes involved in glycogen metabolism, leading to an accumulation of glycogen in various organs. Deficiency of amylo-1-6-glicosidase (debranching enzyme) causes glycogen storage disease type III (GSD III). The main problems that anesthesiologists face in patients with GSD III include hypoglycemia, muscle weakness, delayed awakening due to abnormal liver function, possible difficulty in airway, and cardiomyopathy. In the face of these difficulties, airway preparation and appropriate glucose monitoring and support during the fasting period are important. The doses of the drugs to be used should be calculated considering the increased volume of distribution and decreased metabolic activity of the liver. We present the case of a child with GSD IIIa who underwent dental prosedation under general anesthesia. She was also being prepared for liver transplantation. This case was additionally complicated by the patient's serious allergic reaction to eggs and milk.

• Quality Improvement in Health Care
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• v.29 no.2
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• pp.85-93
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• 2023

Purpose: The predominant approach for mitigating inadequate sampling rates has primarily involved bolstering the volume of education. This study aimed to curtail inadequate sampling rates through the implementation of continuous quality improvement (CQI) activities, tailoring effective methods to the unique needs of each institution. Methods: We developed a sample handling guidebook and implemented QI activities to address this issue. Results: These measures resulted in a 4.7% decrease in inadequate sampling rates, concurrently improving knowledge of sample handling and overall nurse satisfaction. We addressed the root causes of inadequate sampling before laboratory pre-processing by: 1) focusing on systematic rather than erratic errors through CQI activities, 2) revising the sample handling guide, and 3) delivering face-to-face education based on the specific needs of the nursing department. These changes resulted in an additional 0.6% decrease in the inadequate sampling rate. Conclusion: This study demonstrates that the implementation of CQI activities based on evidence derived from a multifaceted causal analysis significantly reduced the inadequate sampling rate compared to previous studies.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.1
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• pp.61-74
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• 2016

This paper presents a case study on the ground settlement and volume loss estimation for slurry pressure balanced shield TBM tunnelling in weathered zone of granite rock. Settlement at each stage of shield tunnelling was analyzed and the volume losses and settlement trough factors were estimated from observations. In addition, using the existing volume loss evaluation method in literature, volume losses were estimated considering ground properties and actual driving parameters. Most of ground settlement occurred during passage of shield skin passage and after backfill grouting, and the measured total volume loss and trough curves appeared to coincide with literature. Shield and tail loss obtained from field measurement were found to be around 90% and 60% of the predictions, where tail loss indicated larger deviation than shield loss.

• Geomechanics and Engineering
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• v.35 no.1
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• pp.29-39
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• 2023

As the intensity of urban underground space development increases, more and more tunnels are planned and constructed, and sometimes it is inevitable to encounter situations where tunnels have to underpass the river embankments. Most previous studies involved tunnels passing river embankments perpendicularly or with large intersection angle. In this study, a project case where two EPB shield tunnels with 8.82 m diameter run parallelly underneath a river embankment was reported. The parallel length is 380 m and tunnel were mainly buried in the moderate / slightly weathered clastic rock layer. The field monitoring result was presented and discussed. Three-dimensional back-analysis were then carried out to gain a better understanding the interaction mechanisms between shield tunnel and embankment and further to predict the ultimate settlement of embankment due to twin-tunnel excavation. Parametrical studies considering effect of tunnel face pressure, tail grouting pressure and volume loss were also conducted. The measured embankment settlement after the single tunnel excavation was 4.53 mm ~ 7.43 mm. Neither new crack on the pavement or cavity under the roadbed was observed. It is found that the more degree of weathering of the rock around the tunnel, the greater the embankment settlement and wider the settlement trough. Besides, the latter tunnel excavation might cause larger deformation than the former tunnel excavation if the mobilized plastic zone overlapped. With given geometry and stratigraphic condition in this study, the safety or serviceability of the river embankment would hardly be affected since the ultimate settlement of the embankment after the twin-tunnel excavation is within the allowable limit. Reasonable tunnel face pressure and tail grouting pressure can to some extent suppress the settlement of the embankment. The recommended tunnel face pressure and tail grouting pressure are 300 kPa and 550 kPa in this study, respectively. However, the volume loss plays the crucial role in the tunnel-embankment interaction. Controlling and compensating the tunneling induced volume loss is the most effective measure for river embankment protection. Additionally, reinforcing the embankment with cement mixing pile in advance is an alternative option in case the predicted settlement exceeds allowable limit.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.12
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• pp.1047-1054
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• 2008

In this paper, the molecular dynamics (MD) simulations are performed with single-crystal copper blocks under simple shear and simple tension to investigate the effect of size and crystal orientation. There are many variances to give influences such as deformation path, temperature, specimen size and crystal orientation. Among them, the crystal orientation has a primary influence on the volume averaged stress. The numerical results show that the volume averaged shear stress decreases as the specimen size increases and as the crystal orientation changes from single to octal. Furthermore, the Schmid factor and yield stress for crystal orientation are evaluated by using the MD simulation on the standard triangle of stereographic projection.