• Journal of Surface Science and Engineering
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• v.57 no.4
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• pp.274-284
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• 2024

In this study, copper foil was electroplated under high current density conditions. We used Polyethylene Glycol (PEG), known for its thermal stability and low decomposition rate, as an inhibitor to form a stable and smooth copper layer on the titanium cathode. The electrolyte was composed of 50 g/L CuSO₄ and 100 g/L H₂SO₄, MPSA as an accelerator, JGB as a leveler, and PEG as a suppressor, and HCl was added as chloride ions for improving plating efficiency. The copper foil electroplated in the electrolyte added PEG which induced to inhibit the growth of rough crystals. As a result, the surface roughness value was reduced, and a uniform surface was formed over a large area. Moreover, the addition of PEG led to priority growth to the (111) plane and the formation of polygonal crystals through horizontal and vertical growth of crystals onto the cathode. In addition, the grains became fine when more than 30 ppm of PEG was added. As the microcrystalline structure changed, mechanical and electrical properties were altered. With the addition of PEG, the tensile strength increased due to grain refinement, and the elongation was improved due to the uniform surface. However, as the amount of PEG added increased, the corrosion rate and resistivity increased due to grain refinement. Finally, it was possible to manufacture a copper foil with excellent electrical and mechanical properties and the best surface properties when electroplating was carried out under the condition of additives with Cl-20 ppm, MPSA 10 ppm, JGB 5 ppm, and PEG 10 ppm.

• Journal of Platform Technology
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• v.11 no.6
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• pp.106-115
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• 2023

In this paper, we propose a sensor data sharing system for the safe and smooth operation of autonomous vehicles on two-way single lanes in traffic-isolated areas and implement the core module, the situational awareness technology. Two-way single lanes pose challenges for autonomous vehicles, particularly when encountering parked vehicles or oncoming traffic, leading to reversing issues. We introduce a system using infrastructure cameras to detect vehicles' approach, enter, and leave on twoway single lanes in real-time, transmitting this information to autonomous vehicles via V2N communication, thereby expanding the sensing range of the autonomous vehicles. The core part of the proposed system is the situational awareness of the two-way single lane using infrastructure cameras. In this paper, we implement this using object detection and tracking technology. Finally, we validate the implemented situational awareness technology using data collected from actual two-way single lanes.

• Herbal Formula Science
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• v.32 no.2
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• pp.141-153
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• 2024

Objective : Ephedrae Herba (Ephedra) has been frequently used in the East Asian traditional medicine including Korea, China and Japan in the clinical treatment of asthma, cold and influenza etc. This study was performed to explore an anti-fibrogenic potential of Ephedra Herba water extract (EHE) using immortalized human hepatic stellate cell line, LX-2 cells. Methods : We examined the anti-fibrogenic effects of EHE on canonical pathway of transforming growth factor-β1 (TGF-β1) signaling in LX-2 cells. Cell viability was measured using the MTT assay. mRNA levels were detected by real-time PCR. Proteins expression were detected by Western blot. Results : Treatment of EHE 30 ㎍/ml did not show any cytotoxicity on LX-2 cells. Pre-treatment of EHE (30 ㎍/mL) significantly inhibited α-smooth muscle actin expression induced by TGF-β1. Additionally, EHE significantly decreased Smad2 and Smad3 phosphorylations, Smad binding element-driven luciferase activity and plasminogen activator inhibitor type 1 expression by TGF-β1. Furthermore, increases of matrix metalloproteinases 2 genes by TGF-β1 was also attenuated by EHE treatment. Conclusion : These results suggest that EHE has an ability to suppress fibrogenic process in activated HSC via inhibition of TGF-β1-TGFBR mediated canonical (Smad dependent) pathway.

• The Research Journal of the Costume Culture
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• v.32 no.4
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• pp.468-480
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• 2024

The purpose of this study is to produce virtual models of women aged in their 60s and to implement the virtual clothing with jackets. We referred to 3D images of standard and obese body types from the 8^th Size Korea and attempted to create avatars based on their images through the various trials. Final virtual models were made to reflect the appearance of women in their 60s. For the standard body type, a 3D image with average body measurements was selected. Based on numerous trials aimed at turning her image into an avatar, the auto-converted avatar on CLO 3D was slimmer than the woman in the original image, and hence it was not suitable for the virtual model. After blending, we converted the image into an uneditable avatar for which only the joint points could be moved, thereby creating an avatar that was identical to the original image. We also selected an image of an obese woman with a "beer bottle" body shape from the 8^th Size Korea. We created an avatar that resembled her shape by also converting it into an uneditable avatar for which only joint points could be moved. To use these avatars in virtual clothing, we removed masks of avatars and made faces, hair styles, and skin tones representing women in their 60s. The moderately-sized classic jackets were smooth on both virtual models and fitted satisfactorily. This study demonstrated the applicability of virtual model production of various body types or ages in special clothing studies.

• Smart Media Journal
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• v.13 no.8
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• pp.67-78
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• 2024

The purpose of this study is to investigate the changes and developments in the administrative system, status, and role of public libraries in our country, and to analyze the spatial composition status according to the inter-cooperation system of public libraries located in Gwangju Metropolitan City. For this purpose, the study referenced the required space and area standards according to the status and role presented in the 2022 Public Library Construction and Operation Manual. Floor plan analysis and spatial composition analysis were conducted on the central libraries of the five districts in Gwangju Metropolitan City. The analysis results revealed redundancies and inefficiencies in the spatial composition of public libraries with similar purposes. It was found that securing the area of public libraries according to the hierarchy of administrative districts is necessary to provide smooth library services to local residents. Additionally, with the opening of the representative library in Gwangju Metropolitan City, the reconfiguration of the existing central library spaces was deemed necessary. This study can be used as a foundational resource for the efficient operation and construction of public libraries in the future.

• Structural Monitoring and Maintenance
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• v.11 no.3
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• pp.173-185
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• 2024

Currently, the electro-hydraulic servo loading control system manufactured by MTS, OpenFresco hybrid test interface software and OpenSees finite element software are widely used in structure laboratories to carry out hybrid test, but there is no relevant public information about full structure pseudo-dynamic test based on the above software and hardware. In order to study the feasibility of using the above software and hardware to carry out full structure pseudo-dynamic test, the full structure pseudo-dynamic virtual experiments of a single degree of freedom (SDOF) structure and a two degrees of freedom (2DOFs) structure are carried out based on the MTS 793 Demo Mode, and the results are respectively compared with the finite element analysis method. The results show that the finite element analysis results and full structure pseudo-dynamic virtual experiment results are highly consistent, which verifies the feasibility of carrying out the full structure pseudo-dynamic test based on the above software and hardware. Then, a three story steel frame full structure pseudo-dynamic test is conducted, and the smooth implementation of full structure pseudo-dynamic test of the three story steel frame further verifies the reliability of thistesting method. The implementation method of carrying out the full structure pseudo-dynamic tests are introduced in detail, which can provide some reference for relevant research.

• International Journal of Precision Engineering and Manufacturing-Green Technology
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• v.9
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• pp.431-441
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• 2021

Gadolinium-doped ceria (GDC) is sought-after as an electrolyte layer in solid oxide fuel cells because of its high ionic conductivity and low treatment temperature. Recently, some studies have been reported to produce a component layer of solid oxide fuel cell using a Roll-to-Roll (R2R) system because of its characteristics of the cost-effective and eco-friendly advantages. However, the brittleness and low density of GDC prevent it from being mass-produced via the R2R continuous process. Therefore, we attempted to improve the density of GDC-based multi-electrolyte layers through an optimized R2R calendaring process. The finite element method was employed to determine suitable materials for the calendering rolls and the maximum calendering pressure that would reduce the thickness and porosity of the coated electrolyte layer without producing cracks in the layer. The effect of the number of calendering processes on the thickness and porosity of the electrolyte layers was examined as well. Silicon and steel were observed to be best-suited as the materials for the top and bottom rolls, respectively. Moreover, the maximum permissible calendering pressure was determined to be 15 MPa, while the ideal number of calendering processes was found to be 5. Experimental observations using scanning electron microscopy confirmed that the optimized calendering process reduced the thickness and porosity of the coated electrolyte layers by 16.99% and 7.04%, respectively. Thus, our findings suggest that large-area, high-density GDC-based multi-electrolyte layers with smooth surfaces can be produced via the R2R process, which can enable mass production of SOFCs.

• International conference on construction engineering and project management
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• 2024.07a
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• pp.1057-1064
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• 2024

The construction industry has witnessed a concerning rise in ladder-related accidents, necessitating the implementation of stricter safety measures. Recent statistics highlight a substantial number of accidents occurring while using ladders, emphasizing the mandatory need for preventative measures. While prior research has explored computer vision-based automatic monitoring for specific aspects such as ladder stability with and without outriggers, worker height, and helmet usage, this study extends existing frameworks by introducing a rule set for co-workers. The research methodology involves training a YOLOv5 model on a comprehensive dataset to detect both the worker on the ladder and the presence of co-workers in real time. The aim is to enable smooth integration of the detector into a mobile application, serving as a portable real-time monitoring tool for safety managers. This mobile application functions as a general safety tool, considering not only conventional risk factors but also ensuring the presence of a co-worker when a worker reaches a specific height. The application offers users an intuitive interface, utilizing the device's camera to identify and verify the presence of coworkers during ladder activities. By combining computer vision technology with mobile applications, this study presents an innovative approach to ladder safety that prioritizes real-time, on-site co-worker verification, thereby significantly reducing the risk of accidents in construction environments. With an overall mean average precision (mAP) of 97.5 percent, the trained model demonstrates its effectiveness in detecting unsafe worker behavior within a construction environment.

• Journal of IKEEE
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• v.28 no.3
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• pp.303-309
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• 2024

This paper proposes a high-gain phased array antenna that can provide private network communication services for large office spaces, factories, and other large-scale facilities, specifically designed for millimeter-wave band 5G (5th generation) networks. The proposed antenna features a 4×4 array structure with eight sub-arrays, each consisting of a 1×2 series array. To achieve high side-lobe characteristics, an offset array structure is applied by shifting even-numbered rows by one unit, combined with power tapering to adjust the size of individual radiating elements. This design achieves a high side-lobe level (SLL) of 22.3 dB and a high gain of 18.1 dBi. Additionally, the antenna provides gain characteristics of at least 15.2 dBi and 17.4 dBi within the intended beam steering range of ±45° in the azimuth direction and ±10° in the elevation direction, ensuring smooth communication services over a wide service area.

• Anatomy and Cell Biology
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• v.55 no.2
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• pp.205-216
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• 2022

Chronic pancreatitis (CP) is an inflammatory disease affects the pancreas with upcoming fibrosis and notable parenchymal destruction. CP poses a high risk for pancreatic carcinoma. The present study aimed to investigate, for the first time up to our knowledge, the effect of olive leaf extract on L-arginine induced CP with referral to some of its underlying mechanisms. Forty adult male albino rats were divided equally into four groups; control, olive leaf extract treated (200 mg/kg orally once daily), CP group (300 mg L-arginine/100 g body weight intraperitoneally, once daily for 3 weeks then every 3 days for the subsequent 3 weeks), and CP treated with olive leaf extract group. At the end of the experiment, body weight, serum glucose, serum insulin, homeostatic model assessment of insulin resistance (HOMA-IR), serum amylase and lipase as well as tissue superoxide dismutase (SOD), and malondialdehyde (MDA) levels were assessed. Pancreatic tissues were subjected to histological and immuno-histochemical studies. The CP group revealed significant decrease in body weight and increase in serum glucose, serum insulin, HOMA-IR score, serum amylase, and serum lipase levels. Significant increase in MDA level and decrease in SOD level were detected. Marked degenerative changes and fibrosis were detected. Upregulation of alpha smooth muscle actin (α-SMA), transforming growth factor beta (TGF-β), caspase-3, and interleukin-6 (IL-6) immunoreactions were implicated in CP pathogenesis. Olive leaf extract alleviated all the examined parameters via its-antioxidant, anti-inflammatory, and anti-fibrotic properties. Olive leaf extract can protect against CP and restore pancreatic functions.