• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1181-1182
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• 2006

The solar power system comprises a solar battery that directly converts light energy to electrical energy with a photovoltaic effect and a power converter system, that is, inverter that converts direct current power, which is generated from solar battery to common alternating current. In this paper, database was constituted through remote monitoring supervision measurement for the long-time positive operation of 3kW solar power system installed within the solar energy positive research complex of Chosun University. As a result of analyzing the reduction of the efficiency of solar battery and inverter that are compositional components of PV system through an analysis on the acquired data, the PV output was proven over 65% of the total output when insolation intensity exceeded 600W/m2 in 2005, and the array conversion efficiency dropped much more than rating; meanwhile, insolation intensity dropped below 600W/m2. Therefore, it has been demonstrated that approximately 35% of the entire amount of PV output operated under the condition that the inverter efficiency rate dropped rapidly by 60 to 70%.

• Smart Structures and Systems
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• v.16 no.3
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• pp.521-535
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• 2015

Vibration-based monitoring is one approach used to perform structural condition assessment. By measuring structural response, such as displacement, dynamic characteristics of a structure may be estimated. Often, the primary dynamic responses in civil structures are below 5 Hz, making accurate low frequency measurement critical for successful dynamic characterization. In addition, static deflection measurements are useful for structural capacity and load rating assessments. This paper presents a DC coupled continuous wave radar to accurately detect both dynamic and static displacement. This low-cost radar sensor provides displacement measurements within a compact, wireless unit appropriate for a range of structural monitoring applications. The hardware components and operating mechanism of the radar are introduced and a series of laboratory experiments are presented to assess the performance characteristics of the radar. The laboratory and field experiments investigate the effect of factors such as target distance, motion amplitude, and motion frequency on the radar's measurement accuracy. The results demonstrate that the radar is capable of both static and dynamic displacement measurements with sub-millimeter accuracy, making it a promising technology for structural health monitoring.

• Korean Journal of Occupational Health Nursing
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• v.18 no.1
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• pp.71-83
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• 2009

Objective: This study was conducted to compare health conditions and problems, health promoting behavior, and risky environment of industrial workers. Methods: The subjects of this study were 1,075 workers in 40 factories, located in Daegu, Korea. Survey data were collected from April 17th, 2006 to April 28th, 2006. CMI (Cornell Medical Index) Health Checklist was used to assess the health problems, Health Rating Scale for health status, HPLP II for health promoting behavior, and environmental risk assessment tool for risky environment. The data were analyzed by One-way ANOVA and Pearson Correlation Coefficient using SPSS 12.0 for windows. Results: The results indicated a significant difference in health problems (F=4.70, p=.000), health conditions (F=2.47, p=.022), health promoting behavior (F=5.67, p=.000), and risky environment (F=14.75, p=.000) among these industrial workers. Conclusion: The results of this study suggest that there is a need to develop customized health care programs for each company to provide differentiated health care to different types of work places. Further studies are required to assess differences in work environment among different types of work places for measures to reduce harmful factors to the environment.

• Journal of Sasang Constitutional Medicine
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• v.30 no.3
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• pp.104-115
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• 2018

Introduction The aim of this study was to report significant improvement of Dyshidrosis(Pompholyx) patient who was diagnosed with 'Soyangin chest-bind symptomatic pattern' based on Sasang Constitutonal medicine. Methods The patient was treated with herbal medicine, acupuncture, as well as western medicine. To evaluate the results of this treatment, the patient assessed discomfort of dyshidrosis by using Numeral Rating Scale(NRS), percentage(%) and we assessed severity of dyshidrosis by using Dyshidrotic Eczema Area and Severity Index(DASI). Results At the time of admission, the degree of discomfort in the dyshidrosis symptoms was NRS 8 and the severity of dyshidrosis was DASI 16(moderate). After the treatment, her symptoms was improved(NRS 0, DASI 0). Sleep, digestion and defecation condition were also improved. Discussion The patient who had frequent recurrence showed a significant improvement of dyshidrosis and accessory symptoms without any side effects, who was treated with Hyeongbangdojeok-san, acupuncture and western medicine.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.747-750
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• 2004

Lightweight concrete is known for its advantage of reducing the self-weight of the structures, reducing the areas of sectional members as well as making the construction convenient. Thus the construction cost can be saved when applied. to . structures such as long-span bridge and high rise buildings. However, the lightweight concrete requires specific design mix method that is quite different from the typical concrete, since using the typical mix method would give rise the material segregation as well as lower the strength by the reduced weight of the aggregate. In order to avoid such problems, it is recommended to apply the design mix method of high performance self-compacting concrete for the lightweight concrete. Therefore, this study introduces a production of self-compacting concrete, PF-modified and improved version of Nan-Su's design mix method of self-compacting concrete. Through a series of test mixes conducted during the study, the quality of the concrete at its fresh condition has been evaluated per the 2nd class rating standards of self-compacting concrete published by JSCE, especially focused in its fluidity, segregation resistance ability, and filling ability.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1215-1217
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• 2007

This paper is proposed a novel method to approximate the maximum power for a photovoltaic inverter system. 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. This paper is proposed MPPT using LRMC method using weather condition of domestic moderate program technique. This paper is proposed the experimental results to verify the effectiveness of the new methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.599-604
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• 2008

An experimental study has been performed to investigate the air-side capacity and pressure drop of the fin-tube heat exchanger for a fan coil unit under a cooling condition. The experimental data of five kinds of slit fin-tube heat exchangers were measured using an air-enthalpy calorimeter and a constant temperature water bath. Cooling capacities at the air and water rating flow rates were larger at the lower inlet water temperature. With increasing the water flow rate, the cooling capacity increased at the constant rate. Under the lower inlet water temperature, since the condensate was generated more on the fin-tube surface, the air-side pressure drop of the heat exchanger was larger.

• 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 Acupuncture Research
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• v.36 no.4
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• pp.277-281
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• 2019

A patient with central post-stroke pain was treated for 4 weeks with scalp acupuncture and traditional Korean medicine (following a cerebral infarction in 2013). The patient presented at Chungju hospital in January 2019 with left side weakness and tingling, numbness in the left hemisphere, chronic pain and dysarthria. Initially, herbal medicine, acupuncture, pharmacupunture, indirect moxibustion, and physiotherapy were administered together with Western medicine, with no improvement in the patient's condition. On Day 5, scalp electroacupuncture (MS1, MS5, MS10, MS11) was introduced. The numbness feeling in the patient's head resolved, and the pain in his upper body decreased. Grip force difference between the left and right hand improved from 3 kg to 0-0.5 kg. Sleep disturbance was resolved after 4 weeks treatment, and his average numeric rating scale score for pain improved from an admission score of 10, to a discharge score of 5. The patient could walk unaided after treatment.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.14 no.1
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• pp.61-76
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• 2019

Objectives : The purpose of this study was to report the clinical results of various medical methods (including Chuna joint mobilization) used to treat a single patient with polyneuritis. Methods : We treated a 46 year-old female patient diagnosed with polyneuritis using various methods, including acupuncture, moxibustion, infrared therapy, herbal medication, Western medication, Chuna manual therapy, and physical therapy. We evaluated the results using the numeric rating scale (NRS), manual muscle test (MMT), active range of motion (ROM), modified barthel index (MBI). Other evaluation scale included Deep tendon reflex and thickness of muscle especially forearm and lower leg. Results : Following treatment using a combination of the above methods, the general overall condition of the patients was significantly improved. Furthermore, the NRS, MMT, MBI, and the active ROM scores were numerically improved. Conclusions : In this case, a single patient with polyneuritis was treated using a combination of Korean and Western medical methods. Although this study provides useful insight into treatment methods, further studies are required to determine the treatment effects of Korean medicine, specifically Chuna manual therapy, in patients with polyneuritis.