• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.9
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• pp.1221-1225
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• 2012

This paper describes CSC(Current Sourced Converters)-based HVDC operational strategy for voltage stability enhancement in the power system. In case of CSC-based HVDC system, rectifier and inverter consume reactive power up to about 60% of converter rating. Therefore, CSC-based HVDC is basically not useful system for voltage stability even if AC filters and shunt capacitors are attached. But, If the particular power system condition is fulfilled, CSC-based HVDC also can be the rapid reactive power source for voltage stability enhancement using a cooperative control with converter and AC filters/Shunt Capacitors. In this paper, the cooperative control algorithm is presented and simulated to ${\pm}80kV$ 60MW HVDC system in Jeju island.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.11a
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• pp.183-186
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• 2007

In modern society, sense of crisis from environmental destruction caused by rapid industrial development, economic growth and improvement of educational level and medicine made environmental preservation and comfortable residential environment a necessary and sufficient condition. Since government conducted 'green building rating system' from 2002, application of pro-environmental elements has been extended. But the concept of substantial pro-environmental housing remains the stage of complex planning yet and application of system to interior space which has the most direct influence on actual dwellers is very poor.

• Journal of Korean Institute of Fire Investigation
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• v.10 no.1
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• pp.87-95
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• 2007

This paper is proposed a novel method to approximate the maximum power for a photovoltaic inverter system and tracking method. It is designed for power systems application and utilities. The proposed Maximum Power Point Tracking (MPPT) control has the advantage to provide a new simple way to approximate the optimal or rated voltage, the optimal or rated current and maximum power rating produced by a solar panel and the photovoltaic inverter. And this straightforward method will be named linear reoriented coordinates method (LRCM) with the advantage that Pmax and $V_{op}$ can be approximated using the same variable as the dynamic model without using complicate approximations or Taylor series. Furthermore tracking method is improved over 50% photovoltaic efficiency. This paper is proposed MPPT using LRMC and tracking method using weather condition of domestic moderate program technique. This paper is proposed the experimental results to verify the effectiveness of the new methods.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.417-420
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• 2003

In this paper, we have designed the ground faults detection and disconnection algorithm at normal rendition of AC 120V to 240V rating voltage. Ground faults in electrical network have the characteristics of low current, 60Hz frequency to 2kHz frequency. The load rendition are no load and 20A load. The controller have the trip level are 6mA with ground faults. Conventional controller does not have the miswiring condition. The Controller algorithm using pic16c71 microprotessor.

• The Journal of Internal Korean Medicine
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• v.37 no.2
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• pp.305-314
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• 2016

Objective: The present study reports on one patient diagnosed with Guillain-Barre syndrome.Method: One patient was treated by Sukjiyanggeun-tang, electroacupuncture, and physical therapy. Any improvement in symptoms was assessed by measuring changes in motor grade; scores in the modified Barthel index, the disability scale, and the numerical rating scale (NRS) of lower back pain; and ambulatory condition during hospitalization.Results: After 48 days of treatment, the patient's symptoms of Guillain-Barre syndrome showed improvement.Conclusions: Traditional Korean medical treatment appeared to be effective in reducing Guillain-Barre syndrome symptoms, but more research is required to confirm these results.

• The Journal of Korean Medicine
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• v.43 no.2
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• pp.110-116
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• 2022

Objectve: To inform a clinical usefulness of Nangan-geon (暖肝煎) decoction to treat a refractory abdominal pain especially in eldery. Methods: This case report presents an 85-year old male patient who had been suffered with a refractory abdominal pain without any abnormality in laboratory test and radiological examination for 5-years. The clinical outcome was observed by numerical rating scale (NRS) of self-reporting method. Results: Based on his previous multiple normal examination results from Western hospitals and clinical features including thin body (19.6 BMI), nocturnal pain around lower abdomen and cold-sensitivity, author diagnosed him as "deficiency and cold of liver-Qi (肝氣虛寒)" similar to intestinal spasm. After prescription with Nangan-geon (暖肝煎) for one month, all symptoms became improved notably (NRS 5), and almost completely recovered as a level of normal condition in 3 months (NRS 1). Conclusion: This study would show the potential of traditional Korean medicine (TKM) therapies for a refractory functional abdominal pain, and especially efficacy of Nangan-geon against cold-pattern of nonspecific abdominal pain in elderly patients.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.597-602
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• 2011

A robust asset management methodology is essential for effective decision-making of maintenance, repair and rehabilitation of a bridge network. It can be achieved by a computer-based bridge management system (BMS). Successful BMS development requires a reliable bridge deterioration model, which is the most crucial component in a BMS, and an optimal management philosophy. The maintenance optimization methodology proposed in this paper is developed for a small bridge network with limited structural condition rating records. . The methodology is organized in three major components: (1) bridge health index (BHI); (2) maintenance and budget optimization; and (3) reliable Artificial Intelligence (AI) based bridge deterioration model. The outcomes of the paper will help to identify BMS implementation problems and to provide appropriate solutions for managing small bridge networks.

• Journal of Sasang Constitutional Medicine
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• v.35 no.4
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• pp.86-95
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• 2023

Introduction This is the first case report of a soyangin suffering from burning feet syndrome who reported a significant improvement after taking Sukjiwhanggosam-tang. Case presentation The patient complained of hot feet, pain and numbness that occurred during the night. The patient was diagnosed with 'Yin deficiency diurnal fever disease' and treated with Sukjiwhanggosam-tang as well as acupuncture and cupping therapy. The degree of improvement in heat sensation, pain and numbness was expressed in numeric rating scale compared to the first visit. Conclusion After treatment, the heat sensation, pain and numbness of feet was decreased significantly, and the condition improved much at night.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.6
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• pp.79-87
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• 2003

Application of combustion stabilization devices such as baffle and acoustic cavity to liquid propellant rocket engine is investigated to suppress high-frequency combustion instability, i.e., acoustic instability. First, these damping devices are designed based on linear damping theory. As a principal design parameter， damping factor is considered and calculated numerically in the chambers with/without these devices. Next, the unbaffled chambers with/without acoustic cavities are tested experimentally for several operating conditions. The unbaffled chamber shows the peculiar stability characteristics depending on the operating condition and it is found to have small dynamic stability margin. As a result, the acoustic cavity with the present design has little stabilization effect in this specific chamber. Finally， stability rating tests are conducted with the baffled chamber, where evident combustion stabilization is observed, which indicates sufficient damping effect.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.3
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• pp.98-108
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• 2011

Objectives: The purpose of this study is to investigate the relationship between granulocyte/lymphocyte ratio and dysmenorrhea, history of gynecological disease, heart rate varibility(HRV). Methods: From May 1st 2011 to July 10th 2011, a total of 40 female subjects (age 20-39) were recruited. We evaluated the menstruation condition by questionnaires including VAS(Visual Analog Scale), VRS(Verbal Rating Scale) and MVRS (Multidimensional Verbal Rating Scale), also measured subject's WBC differential count and HRV. Results: 1. There was no statistically significant difference in granulocyte/lymphocyte ratio according to menstruation cycle, duration, amount, color, and blood clot. 2. There was no statistically significant difference in VAS, VRS, MVRS mean scores between normal group and abnormal group according to granulocyte/ lymphocyte ratio. 3. The past prevalence of gynecological disease of abnormal group showed significantly higher compared with that of normal group($x^2$=6.578, p=0.010). 4. LF/HF ratio and granulocyte ratio significantly showed positive correlation ($r_s$=0.311 p=0.048) and LF/HF ratio and lymphocyte ratio significantly showed negative correlation($r_s$=-0.319 p=0.045). Conclusion: These findings suggest that the gynecologic diseases are related to disorder of autonomic nervous system, but not dysmenorrhea. And the balance state of sympathetic/parasympathetic nerve infered through granulocyte/lymphocyte ratio and HRV seems to be consistent. However, reconfirmation through further studies is needed.