• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1994년도 특별강연 및 추계학술발표 개요집
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• pp.111-114
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• 1994

This paper describes a method to measure a weldment surface temperature for estimating variations of the weld pool size in the gas metal arc(GMA) welding processes. An Infrared sensing system is designed to measure the radiation emitted from the top surface of the weldment, The interference effect of the electric arc to the measurement is rejected by detecting the low peaks of the noisy signal. An optimizing criterion, in which the correlation between the weld quality and the measured temperature is maximized, is also proposed to determine the optimal measurement location.

• 한국정보통신학회논문지
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• 제8권7호
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• pp.1532-1536
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• 2004

지금까지는 직물의 신축성 측정은 작업자의 과거 경험을 바탕으로 작업자의 수작업에 의해 측정하였기 때문에 계량화된 신축성 데이터가 존재하지 않았다. 본 논문에서는 실시간으로 직물의 신축성 계수를 측정하기 위하여 특별히 제작된 로드 셀을 이용한 측정 장비가 소개된다. 측정방법은 직물에 따라 다르게 나타나는 로드 셀에 가해진 전압차를 기본으로 한다. 신축성이 강한 직물은 로드 셀에 강한 전압이 발생하며 신축성이 약할수록 약한 전압이 발생한다. 제안된 시스템은 직물의 시각화, 의류봉제, 품질관리 등에 이용될 뿐만 아니라 정량화된 데이터들은 B2B 전자상거래 시스템에 적용될 수 있다.

• Journal of Power Electronics
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• 제16권3호
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• pp.1163-1175
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• 2016

In recent years, microgrids have been the focus of considerable attention in distributed energy distribution. Microgrids contain a large number of power electronic devices that can potentially cause negative impedance instability. Harmonic impedance is an important tool to analyze stability and power quality of microgrids. Harmonic impedance can also be used in harmonic source localization. Precise measurement of microgrid impedance and analysis of system stability with impedances are essential to increase stability. In this study, we introduce a new square wave current injection method for impedance measurement and stability analysis. First, three stability criteria based on impedance parameters are presented. Then, we present a new impedance measurement method for microgrids based on square wave current injection. By injecting an unbalanced line-to-line current between two lines of the AC system, the method determines all impedance information in the traditional synchronous reference frame d-q model. Finally, the microgrid impedances of each part and the overall microgrid are calculated to verify the measurement results. In the experiments, a simulation model of a three-phase AC microgrid is developed using PSCAD, and the AC system harmonic impedance measuring device is developed.

• 전기학회논문지
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• 제59권9호
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• pp.1560-1565
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• 2010

The renewable resource are getting more attentions with increased concerns on the depletion of fossil fuels and several environmental issues like emission problem. Wind power is a representative option among several renewable sources and the generation capacity using wind power is being increased. However, the wind generation is so volatile on its output characteristic, so it is required to assess the grid impact of wind power generation by measuring the fluctuation effect more precisely. This paper proposes the method for measuring the generation output according to IEC 61400-21(Measurement and assessment of power quality characteristics of grid connected wind turbines) to assess the power quality of wind turbine generation. In addition, it shows an application case to a small-scale wind power generator. In the case study, it suggests a structure design of the proposed measurement instrument both on hardware and software aspects, which is composed of a remote monitoring & data analysis program and an FPGA based real-time signal processing device.

• International journal of advanced smart convergence
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• 제5권2호
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• pp.73-79
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• 2016

Remote sensing and measurement are of paramount importance of providing information on the state of water quality in water bodies. The formation and growth of cyanobacteria is of serious concern to in land aquatic life forms and human life. The main cause of water quality deterioration stems from anthropogenic induced eutrophication. The goal of this research to quantify and determine the spatial distribution of cyanobacteria concentration in the water using remote sensing technique. The standard approach to measure water quality based on the direct measurement of the fluorescence of the chlorophyll a in the living algal cells and the same approach used to detect the phycobilin pigments found in blue-green algae (a.k.a. cyanobacteria), phycocyanin and phycoerythrin. This paper propose the emerging sensor design to measure the water quality based on the optical analysis by fluorescence of the phycocyanin pigment. In this research, we developed an method to sense and quantify to derive phycocyanin intensity index for estimating cyanobacteria concentrations. The development of the index was based on the reflectance difference between visible light band 620nm and 665nm. As a result of research this paper presents, an optical biological sensor design information to measure the Phycocyanin parameters in water content.

• 임상간호연구
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• 제14권1호
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• pp.33-44
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• 2008

Purpose: This study was performed to determine the effects of foot reflexology on pain and quality of sleep in patients with terminal cancer. Method: Quai-experimental research design was used. The subjects of this study were consisted of 19 for experimental group and 18 for control group. Visualue Scale(VAS) was used as the measurement tool of pain in this study, Verra & Snyder-Halpern Sleep Scale(VSH) and Visual Analogue Scale(VAS) were used as the measurement tool of perceived quality of sleep. Data were analyzed using statistical methods such as frequency, percent, $x^2$-test, t-test using SPSS WIN 12.0 program. Results: The hypothesis 1 that the experimental group with reflexology has less degree of pain than the control group without reflexology was supported (t=5.41, p<.001). The hypothesis 2 that the experimental group with reflexology has higher degree of VSH Scale than the control group without reflexology was supported(t=2.37, p=.02). The hypothesis 3 that the experimental group with reflexology has the difference among the mean of sleep VAS Scale during the 12 measurement periods was not supported(F=1.63, p=.08), and no significant interactions between group and time. Conclusion: It is considered that reflexology is effective for reducing cancer pain and improving quality of sleep in patients with terminal cancer.

• 조명전기설비학회논문지
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• 제25권8호
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• pp.88-98
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• 2011

Development and use of renewable energy due to environmental problems and depletion of energy affect grid-connected power system around the world. Therefore this paper analyzes the characteristic of gird connected photovoltaic power generation system which it is available to connect the utility. Renewable energy photovoltaic power system has been linked to the system to analyze the impact of photovoltaic system. MATLAB / Simulink program is modeled and analyzed on power quality of a photovoltaic power plant. It is measured that power data for the Grid connected photovoltaic power plant with instantaneous measuring, 3sec measuring, 10min measuring for 7 days. Harmonic field measurement have shown that the harmonic contents of a waveform varies with time. A cumulative probability approach is the most commonly used method to solve time varying harmonics. so, it is used 50[%] cumulative probability approach. This paper provides an in depth analysis on power quality field measurement of the Grid connected photovoltaic power plant.

• Journal of Biosystems Engineering
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• 제32권3호
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• pp.166-172
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• 2007

Egg quality indices are related with freshness, size of air chamber, loss of weight, and viscosity of the yolk and the protein. However, since the described quality parameters require measured in a destructive way, it is not suitable to inspect the egg quality with complete enumeration. Therefore, this study was performed to investigate the potential of image analysis method for evaluation of internal egg quality. Samples of 90 fresh eggs were collected immediately after laying and stored up to 24 days. Five eggs were randomly drawn from each storage condition (packing vs unpacking) at a regular interval and loss of weight, specific gravity and size of air chamber were measured. The image analysis for nondestructive measurement of size of air chamber was also studied. Results showed that the egg weight and gravity gradually decreased with increasing of storage days, while the size of air chamber linear increased caused by evaporation of water through the shell. A relationship a between conventional method and the image analysis method for measuring the size of air chamber was developed with the correlation coefficient of 0.928. The new finding implied that image analysis might provide a useful nondestructive tool to assess internal egg quality.

• 한국정보시스템학회지:정보시스템연구
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• 제30권3호
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• pp.47-64
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• 2021

Purpose This study measures the degree of improvement in statistical quality experienced by data users when the data of a more convenient measurement method is extended to the analysis target to improve the quality of fine dust statistics service, and the method of expressing analysis data is revised. Ultimately, the main purpose is to explore how it can affect the quality of life of citizens. Design/methodology/approach As it was an issue the emerged as the most important issue at the time, various parties (government, private company, academia, civic groups, etc.) conducted multifaced research on fine dust, but they all focused on measuring technology and demonstrating its effectiveness there was only. This researcher redesigned the study from the viewpoint of statistical data users by changing the research subject from the technology itself to user, different from the existing research cases. The questionnaire method and structural equation were used in the study, and fine dust statistics generated through the existing method and the expanded/revised method were provided and compared for a total of 200 people. Findings Based on the results of the study, I would like to suggest what each entity should ultimately focus on to resolve the fine dust issue in the future.

• 대한치과보철학회지
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• 제44권4호
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• pp.405-413
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• 2006

Purpose : This study was conducted to evaluate the effect of denture placement on nutrition status and quality of life in the urban elderly Material and method : The first survey was conducted from 45 targeted elderly people(25 experimental group, 20 control). In the first survey, information on general characteristics, chewing ability, food intake and nutrient intake, anthropometric measurement, and degree of satisfaction in life were obtained. The second survey was conducted to evaluate the effect of denture placement with same method as the first survey. Results : Before denture placement, there are no statistical significant differences (in general characteristics, chewing ability, nutrient intake, anthropometric measurement, and degree of satisfaction in life) between experimental group and control. But after denture placement, survey shows that there is statistically significant difference in chewing ability between two groups. The experimental group have higher intake of energy, protein, carbohydrate, iron, and vitamin C. in nutrient intake. And after denture replacement, there is significant improvement in degree of satisfaction in life. After denture placement there are significant changes in agitation and attitude toward own aging according to Lawton's factor classification. Conclusion: In short, this study shows that chewing ability improvement of the elderly has strong positive effects to their food intake, nutrient status and quality of life.