• Journal of the Korean Magnetics Society
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• v.21 no.4
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• pp.132-135
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• 2011

The exchange bias field ($H_{EX}$) and the coercivity ($H_C$) variation and change depending on the thickness of intermediately super-soft magnetic NiFeCuMo layer with different thickness of the bottom NiFe layer were investigated. The $H_{EX}$ of triple pinned NiFe(4 nm)/NiFeCuMo($t_{NiFeCuMo}$= 1 nm)/NiFe(4 nm)/FeMn multilayer has the maximum value more less than one of single pinned NiFe(8 nm)/FeMn layer. If NiFeCuMo layer is inserted each into between the pinned and free NiFe layers, we can be used as GMR-SV device for a bio-sensor that has improved magnetic sensitivity.

• Research in Plant Disease
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• v.13 no.1
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• pp.57-60
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• 2007

A rhizopus soft rot caused by Rhizopus stolonifer occurred sporadically on grape in orchard in Gyeongsang-nam-do Agricultural Research and Extension Services and in Wholesale Market of Agricultural Products in Jinju city. The infected fruits were rapidly water-soaked, softened and eventually rotted, and the symptoms were initiated from wounds or cracks occurred at harvest time. Sporangiophores were $850{\sim}1,800{\mu}m$ in length and $12{\sim}23{\mu}m$ in width. Sporangia were globose or hemispheric and $80{\sim}190{\mu}m$ in size. The color of sporangia was white and cottony at first and gradually to brownish black, bearing abundant spores when it matured. Columella were hemispheric and $70{\sim}95{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $8{\sim}22{\times}6{\sim}10{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was 25$^{\circ}C$. On the basis of mycological characteristics and pathogenicity to grape (Vitis vinifera), the causal fungus was identified as Rhizopus stolonifer (Ehrenberg ex. Fr,) Lind. This is the first report of Rhizopus soft rot by R. stolonifer on grape (V. vinifera) in Korea.

• Journal of Intelligence and Information Systems
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• v.29 no.2
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• pp.241-265
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• 2023

A corporate insolvency prediction model serves as a vital tool for objectively monitoring the financial condition of companies. It enables timely warnings, facilitates responsive actions, and supports the formulation of effective management strategies to mitigate bankruptcy risks and enhance performance. Investors and financial institutions utilize default prediction models to minimize financial losses. As the interest in utilizing artificial intelligence (AI) technology for corporate insolvency prediction grows, extensive research has been conducted in this domain. However, there is an increasing demand for explainable AI models in corporate insolvency prediction, emphasizing interpretability and reliability. The SHAP (SHapley Additive exPlanations) technique has gained significant popularity and has demonstrated strong performance in various applications. Nonetheless, it has limitations such as computational cost, processing time, and scalability concerns based on the number of variables. This study introduces a novel approach to variable selection that reduces the number of variables by averaging SHAP values from bootstrapped data subsets instead of using the entire dataset. This technique aims to improve computational efficiency while maintaining excellent predictive performance. To obtain classification results, we aim to train random forest, XGBoost, and C5.0 models using carefully selected variables with high interpretability. The classification accuracy of the ensemble model, generated through soft voting as the goal of high-performance model design, is compared with the individual models. The study leverages data from 1,698 Korean light industrial companies and employs bootstrapping to create distinct data groups. Logistic Regression is employed to calculate SHAP values for each data group, and their averages are computed to derive the final SHAP values. The proposed model enhances interpretability and aims to achieve superior predictive performance.

• Journal of Biomedical Engineering Research
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• v.30 no.1
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• pp.18-22
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• 2009

Laser has been widely used in various fields of medicine. Recently, noninvasive low-level laser therapeutic medical devices have been introduced in market. However, low-level laser cannot deliver enough photon density to expect positive therapeutic results in deep tissue layer due to the light scattering property in tissue. In order to overcome the limitation, this study was aimed to develop a negative pressure applied low-level laser probe to optimize laser transmission pattern and therefore, to improve photon density in soft tissue. In order to evaluate the possibility of clinical application of the developed laser probe, ex-vivo experiments were performed with porcine skin samples and laser transmissions were quantitatively measured as a function of tissue compression. The laser probe has an air suction hole to apply negative pressure to skin, a transparent plastic body to observe variations of tissue, and a small metallic optical fiber guide to support the optical fiber when negative pressure was applied. By applying negative pressure to the laser probe, the porcine skin under the metallic optical fiber guide is compressed down and, at the same time, low-level laser is emitted into the skin. Finally, the diffusion images of laser in the sample were acquired by a CCD camera and analyzed. Compared to the peak intensity without the compression, the peak intensity of laser increased about $2{\sim}2.5$ times and FWHM decreased about $1.67{\sim}2.85$ times. In addition, the laser peak intensity was positively and linearly increased as a function of compression. In conclusion, we verified that the developed low-level laser probe can control the photon density in tissue by applying compression, and therefore, its potential for clinical applications.

• The Korean Journal of Pain
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• v.29 no.3
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• pp.158-163
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• 2016

Background: Phenol and alcohol have been used to ablate nerves to treat pain but are not specific for nerves and can damage surrounding soft tissue. Lidocaine at concentrations > 8% injected intrathecal in the animal model has been shown to be neurotoxic. Tests the hypothesis that 10% lidocaine is neurolytic after a peri-neural blockade in an ex vivo experiment on the canine sciatic nerve. Methods: Under ultrasound, one canine sciatic nerve was injected peri-neurally with 10 cc saline and another with 10 cc of 10% lidocaine. After 20 minutes, the sciatic nerve was dissected with gross inspection. A 3 cm segment was excised and preserved in 10% buffered formalin fixative solution. Both samples underwent progressive dehydration and infusion of paraffin after which they were placed on paraffin blocks. The sections were cut at $4{\mu}m$ and stained with hemoxylin and eosin. Microscopic review was performed by a pathologist from Henry Ford Hospital who was blinded to which experimental group each sample was in. Results: The lidocaine injected nerve demonstrated loss of gross architecture on visual inspection while the saline injected nerve did not. No gross changes were seen in the surrounding soft tissue seen in either group. The lidocaine injected sample showed basophilic degeneration with marked cytoplasmic vacuolation in the nerve fibers with separation of individual fibers and endoneurial edema. The saline injected sample showed normal neural tissue. Conclusions: Ten percent lidocaine causes rapid neurolytic changes with ultrasound guided peri-neural injection. The study was limited by only a single nerve being tested with acute exposure.

• Journal of the Korean Society of Costume
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• v.35
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• pp.253-264
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• 1997

Han-Bok presents a unique consumption ex-perience different from Western dress which is common to our clothing life. This study is intended to propose the necessity of broad-ening deepening and systematizing a research related to the social aspects of Han-bok. A questionnaire consisted of 10 statements of attitude to Han-Bok 7 statements of the evaluation of the occasional appropriateness of Han-Bok preference questions about style color harmony and decorative materials of han-Bok was developed which includes 5 opinion statement of the importance of tra-ditiona and some demographic variables. During December 1996 and January 1997 the women aged above 20 responded to it and finally 702 data was analyzed. Korean urban women have positive attitude to Han-Bok And the conceit about Han-Bok was significantly higher than the intention to wear it . The most properly evaluated occasion for wearing han-Bok was 'holdays' like Seolnal and chuseok Han-Bok was evaluated im-proper for casual wear and out wear. Factor analysis of 7 occasions determined 3 factors; traditional occasion special occasion and cas-ual occasion. It is needed to identify the ef-ficiency of Han-Bok according to each differ-ent occasion. Korean urban women preferred the style of traditional line soft color and modern har-mony. In a viewpoint of tradition they put more importance in the line of Han-Bok that they do in the color of it.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.561-569
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• 1999

In this paper, the diode bridge-type ZVT(Zero- Voltage Transition) inverter is proposed. It consists of one a auxiliaI${\gamma}$ switch, three resonant inductors and six blockin당 diodes. So, the main advantage of the proposed t torXJ!ogy is the reduction of the auxiliar${\gamma}$ switch compare to the conventional ZVT inverter. The topology of t the propostxl lVT inverter is analyztxl with a description of the control conditions based on the load current. A And the resonant period control for operating the proposed inverter optimally is discussed by using resonant i inductor current ftxxlback. To verify the proposed topology, the detailed simulation and exJX끼mental results i indicate that zero volta당e operation during transition can be achieved.

• Journal of Audiology & Otology
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• v.25 no.4
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• pp.217-223
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• 2021

Background and Objectives: In cochlear implant (CI) surgery, the results and causes of revision and reimplantation may guide surgeons in establishing surgical protocols for revision surgery with safe audiological outcomes. The aim of this study was to review our experience in terms of etiology, surgical strategy, and hearing outcomes in pediatric patients who underwent CI removal and reimplantation. Subjects and Methods: All patients received implants of the same brand. Pre and postoperative Categories of Auditory Performance score and aided free-field pure tone audiometry thresholds were noted. In vivo integrity tests were performed for each patient and the results of ex vivo tests of each implant were obtained from manufacturer. Results: A total of 149 CIs were placed in 121 patients aged <18 years. The revision rate in children was 6.7% (10/121 children). Six patients had a history of head injury leading to a hard failure. The causes of reimplantation in others were soft failure (n=1), electrode migration (n=1), infection (n=1), and other (n=1). All patients showed better or similar postreimplantation audiological performance compared with pre-reimplantation results. Conclusions: It is very important to provide a safe school and home environment and educate the family for reducing reimplantation due to trauma. Especially for active children, psychiatric consultation should be continued postoperatively.

• Korean Journal of Audiology
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• v.25 no.4
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• pp.217-223
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• 2021

Background and Objectives: In cochlear implant (CI) surgery, the results and causes of revision and reimplantation may guide surgeons in establishing surgical protocols for revision surgery with safe audiological outcomes. The aim of this study was to review our experience in terms of etiology, surgical strategy, and hearing outcomes in pediatric patients who underwent CI removal and reimplantation. Subjects and Methods: All patients received implants of the same brand. Pre and postoperative Categories of Auditory Performance score and aided free-field pure tone audiometry thresholds were noted. In vivo integrity tests were performed for each patient and the results of ex vivo tests of each implant were obtained from manufacturer. Results: A total of 149 CIs were placed in 121 patients aged <18 years. The revision rate in children was 6.7% (10/121 children). Six patients had a history of head injury leading to a hard failure. The causes of reimplantation in others were soft failure (n=1), electrode migration (n=1), infection (n=1), and other (n=1). All patients showed better or similar postreimplantation audiological performance compared with pre-reimplantation results. Conclusions: It is very important to provide a safe school and home environment and educate the family for reducing reimplantation due to trauma. Especially for active children, psychiatric consultation should be continued postoperatively.

• Journal of Life Science
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• v.25 no.6
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• pp.693-702
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• 2015

Blocking new blood-vessel formation (angiogenesis) is now recognized as a useful approach to the therapeutic treatment of many solid tumors. The best validated approach to date is to target the vascular endothelial growth-factor (VEGF) pathway, a key regulator of angiogenesis. Many natural products and extracts that contain a variety of chemopreventive compounds have been shown to suppress the development of malignancies through their anti-angiogenic properties. Phellodendron amurense, which is widely used in Korean traditional medicine, has been shown to possess antitumor, antimicrobial, and anti-inflammatory properties, among others. The present study investigated the effects of P. amurense hot-water extract (PAHWE) on angiogenesis, a key process in tumor growth, invasion, and metastasis. To investigate PAHWE’s anti-angiogenic properties, this study’s authors performed an analysis of angiogenesis and endothelial-cell proliferation, migration, invasion, and tube formation, as well as zymogram assays and the rat aortic ring-sprouting assay. PAHWE inhibited cell growth, mobility, and vessel formation in response to VEGF in vitro and ex vivo. Furthermore, it reduced VEGF-induced intracellular signaling events, such as the activation of matrix metalloproteinases (MMPs) -2 and -9. These results indicate that PAHWE’s anti-angiogenic properties might lead to the development of potential drugs for treating angiogenesis-associated diseases such as cancer.