• Journal of Power Electronics
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• v.10 no.6
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• pp.673-679
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• 2010

Input-series-output-parallel (ISOP) connected DC-DC converters enable low voltage rating switches to be used in high voltage input applications. In this paper, a DSP is adopted to generate digital phase-shifted PWM signals and to fulfill the closed-loop control function for ISOP connected two full-bridge DC-DC converters. Moreover, a stable output current sharing control strategy is proposed for the system, with which equal sharing of the input voltage and the load current can be achieved without any input voltage control loops. Based on small signal analysis with the state space average method, a loop gain design with the proposed scheme is made. Compared with the conventional IVS scheme, the proposed strategy leads to simplification of the output voltage regulator design and better static and dynamic responses. The effectiveness of the proposed control strategy is verified by the simulation and experimental results of an ISOP system made up of two full-bridge DC-DC converters.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.271-275
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• 2004

A fast switching thyristor with a superior trade-off property between the on-state voltage drop and the turn-off time could be fabricated by the proton irradiation method. After fabricating symmetric thyristor dies with a voltage rating of 1,600V from $350{\mu}m$ thickness of $60{\Omega}cm$ NTD-Si wafer and $200{\mu}m$ width of N-base drift layer, the local carrier lifetime control by the proton irradiation was performed with help of the HI-13 tandem accelerator in China. The thyristor samples irradiated with 4.7MeV proton beam showed a superior trade-off relationship of $V_{TM}=1.55V\;and\;t_q=15{\mu}s$ attributed to a very narrow layer of short carrier lifetime(${\sim}1{\mu}s$) in the middle of its N-base drift region. To explain the small increase of $V_{TM}$, we will introduce the effect of carrier compensation by the diffusion current at the low carrier lifetime region.

• Structural Engineering and Mechanics
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• v.13 no.2
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• pp.187-209
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• 2002

The infrastructure system in the United States has been aging faster than the resource available to restore them. Therefore decision for allocating the resources is based in part on the condition of the structural system. This paper proposes to use neural network to predict the overall rating of the structural system because of the successful applications of neural network to other fields which require a "symptom-diagnostic" type relationship. The goal of this paper is to illustrate the potential of using neural network in civil engineering applications and, particularly, in bridge evaluations. Data collected by the Tennessee Department of Transportation were used as "test bed" for the study. Multi-layer feed forward networks were developed using the Levenberg-Marquardt training algorithm. All the neural networks consisted of at least one hidden layer of neurons. Hyperbolic tangent transfer functions were used in the first hidden layer and log-sigmoid transfer functions were used in the subsequent hidden and output layers. The best performing neural network consisted of three hidden layers. This network contained three neurons in the first hidden layer, two neurons in the second hidden layer and one neuron in the third hidden layer. The neural network performed well based on a target error of 10%. The results of this study indicate that the potential for using neural networks for the evaluation of infrastructure systems is very good.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.4
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• pp.59-65
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• 2018

PURPOSE: The purpose of the present study is to investigate the changes in the cognitive function of elderly dementia patients residing in a residential care facility, following six weeks of brain-computer interface (BCI)-based cognitive training and to determine whether BCI-based cognitive training effectively improves their cognitive functions. METHODS: Thirty subjects diagnosed with dementia were randomly assigned to either the experimental or control group. Pre- and post-test cognitive function assessments were conducted using the mini mental state examination-Korean (MMSE-K) and Korean-dementia rating scale (K-DRS). The experimental group received BCI-based cognitive training, which consisted of games such as flying a ball and exploding a bomb, while the control group participated in music listening activities and National Health Gymnastics. Both groups engaged in a total of 18 sessions (3 times per week for 6 weeks, for 40 minutes per session). RESULTS: After 6 weeks of intervention, the experimental group had significantly increased MMSE-K scores ($19.53{\pm}1.30$ to $22.20{\pm}1.15$; p<.0011) and total K-DRS scores ($87.20{\pm}4.16$ to $99.33{\pm}1.15$; p<.0011). In addition, the experimental group showed greater cognitive improvements than the control group. CONCLUSION: The results of this study suggest that BCI-based cognitive training is a positive intervention tool for improving the cognitive function of dementia patients.

• Journal of Oriental Neuropsychiatry
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• v.29 no.4
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• pp.305-314
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• 2018

Objectives: The objective of this study was to report the clinical effectiveness of the complex Korean medicine therapy and M&L (Mindfulness & Loving presence) psychotherapy on the patient with panic disorder. Methods: The subject for this study was the patient diagnosed with panic disorder who complained about intermittent panic attack and accompanying insomnia. During the treatment period, the patient received complex Korean therapy and M&L psychotherapy. The clinical effects were evaluated through Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HDRS), State-Trait Anxiety Inventory (STAI), Panic Disorder Severity Scale (PDSS), and Pittsburgh Sleep Quality Index (PSQI). Results: After the complex Korean medicine therapy and M&L psychotherapy, the overall symptoms of depression, anxiety, panic disorder and insomnia of the patient were lessened in a relatively short period. No specificities or adverse effects were reported during the treatment period. Conclusions: This study established that the complex Korean medicine therapy and M&L psychotherapy was effective in treating patients with panic disorder.

• Journal of Oriental Neuropsychiatry
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• v.30 no.3
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• pp.275-285
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• 2019

Objectives: This study was performed to review the research trends in the treatment of Tai Chi on anxiety. Methods: We searched for articles in Pubmed and China National Knowledge Infrastructure (CNKI) from January 2009 to December 2018. The selected studies were evaluated by Jadad Scale. Results: One pre-post comparison study and seven controlled clinical trials were selected. HAMA (Hamilton Rating Scale for Anxiety) and STAI (State Anxiety Inventory) were the most frequently used diagnostic criteria. For outcome measurement, STAI was again the most commo. From Jadad Quality Assessment Scale of 8 articles, the overall quality of the studies was low. Conclusions: According to this study, it seemed that Tai Chi treatment on anxiety disorder is an effective and safe intervention. Therefore, based on this study, more clinical research on diverse forms of treatments of anxiety disorder should be performed in Korean medicine in the near future.

• International Journal of Computer Science & Network Security
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• v.21 no.12spc
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• pp.513-520
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• 2021

The purpose of the article is to study the impact of digitalization on the transformation of the banking system, taking into account current innovative development trends. The article analyzes the impact of key factors on the development of the digital economy. Ukraine's ranking positions in terms of digital competitiveness are shown. The necessity of using digital technologies in the sphere of banking activity is substantiated. The dynamics of changes in the number of operating banks in Ukraine is analyzed. The directions of introduction of information technologies in the sphere of banking activity are determined. An analysis of changes in the share of the population of individual EU member states that use the Internet for Internet banking. It is noted that modern transformation trends, digitalization of the economy have a significant impact on the landscape of the banking sector, in this context, the rating of Ukrainian banks in the categories of "Internet Banking" and "Mobile Banking". The advantages and disadvantages of using the capabilities of Internet banking are identified. Based on the study, the importance of expanding the boundaries of digitalization of the domestic banking system is substantiated, which will further increase the level of availability of online services in the field of banking. Prospects for further research are identified in the study of the impact of digitalization on the development of the banking system of foreign countries.

• Journal of Acupuncture Research
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• v.39 no.4
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• pp.317-322
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• 2022

Gold thread therapy (GTT) continuously stimulates acupoints and is used to treat chronic conditions/diseases such as chronic lumbar pain. During the procedure gold thread is embedded into the skin and although gold thread is medically pure, GTT is an irreversible treatment where there is limited evidence on its safety. Here, we report a case of a 79-year-old woman being treated for low back pain who developed side effects following moving cupping therapy at a site of GTT (performed in the 1970s). Adverse reactions causing radiating pain persisted more than at least 9 days following moving cupping therapy. The symptoms of pain were evaluated using the numerical rating scale, and changes in tenderness and the state of bruising was recorded. Low back pain improved but the radiating low leg pain did not improve. This case highlights the need for caution when performing moving cupping therapy where GTT has been previously performed.

• Computers and Concrete
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• v.31 no.6
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• pp.469-484
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• 2023

The response mechanism of simply supported two-way reinforced concrete (RC) slabs under fire was numerically studied from the view of stress redistribution using the finite element software ABAQUS. Results show that: (1) Simply supported two-way RC slabs undergo intense stress redistribution, and their responses show four stages, namely elastic, elastic-plastic, plastic and tensile membrane stages. There is no cracking in the fire area of the slabs until the tensile membrane stage. (2) The inverted arch effect and tensile membrane effect improve the fire resistance of the two-way slabs. When the deflection is L/20, the slab is in an inverted arch effect state, and the slab still has a good deflection reserve. The deformation rate of the slab in the tensile membrane stage is smaller than that in the elastic-plastic and plastic stages. (3) Fire resistance of square slabs is better than that of rectangular slabs. Besides, increasing the reinforcement ratio or slab thickness improves the fire resistance of the slabs. However, an increase of cover thickness has little effect on the fire resistance of two-way slabs. (4) Compared with one-way slabs, the time for two-way slabs to enter the plastic and tensile cracking stage is postponed, and the deformation rate in the plastic and tensile cracking stage is also slowed down. (5) The simply supported two-way RC slabs can satisfy with the requirements of a class I fire resistance rating of 90 min without additional fire protection.

• Korean Journal of Psychosomatic Medicine
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• v.22 no.2
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• pp.121-129
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• 2014

Objectives : This study was to assess the prevalence and its correlates of restless legs syndrome(RLS) in outpatients with bipolar disorder. Methods : A total of 100 clinical stabilized bipolar outpatients were examined. The presence of RLS and its severity were assessed using the International Restless Legs Sydrome Study Group(IRLSSG) diagnostic criteria. Beck's Depression Inventory(BDI), Spielberg's State Anxiety Inventory(STAI-X-1), Pittsburgh Sleep Quality Index(PSQI), Korean version Drug Attitude Inventory(KDAI-10), Subjective Well-Beings under Neuroleptic Treatment Scale-Short Form(SWN-K) and Barnes Akathisia Rating Scale(BARS) were used to evaluate the depressive symptomatology, level of anxiety, subjective quality of sleep, subjective feeling of well-being, drug attitude, presence of akathisia, respectively. Results : Of the 100 bipolar outpatients, 7(7%) were met to full criteria of IRLSSG and 36(36%) have at least one of the 4 IRLSSG criterion. Because of relatively small sample size, non-parametric analysis were done to compare the characteristics among 3 groups(full-RLS, 1 ${\geq}$positive RLS-symptom and Non-RLS). There were no significant differences in sex, age, and other sociodemographic and clinical data among 3 groups. BDI, STAI-X-1 and PSQI are tended to be impaired in RLS and 1 ${\geq}$positive RLS-symptom groups. Conclusions : This is the first preliminary study for studying the prevalence and its correlates of RLS in bipolar disorder. The results shows that relatively small proportion of RLS was present in bipolar disorder patients when compared to patients with schizophrenia. Same tendencies shown in schizophrenic patients were found that bipolar patients with RLS had more depressive symptoms, state anxiety and poor subjective sleep quality. Further systematic studies may be needed to find the characteristics of RLS in bipolar patients.