• Journal of the Korea Society for Simulation
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• v.29 no.1
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• pp.23-30
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• 2020

In this paper, we theoretically examine the characteristics of an Artificial Magnetic Conductor (AMC) constructed of a perfect electric conductor and a normal material having permittivity ε_r, permeability μ_r, and thickness L. First, we derived rigorous equations to describe the infinite AMC structure. Then, we studied how the AMC's characteristics are affected by changes in ε_r, μ_r and L. The operating center frequency exhibiting a 0° reflection coefficient phase occurs when L is one quarter of a guide wavelength. Therefore, the AMC thickness can be reduced by using a material having a high product of ε_r and μ_r. As the ratio μ_r/ε_r increases, the bandwidth of the AMC increases (maximum value: 200 %), and its operating frequency decreases. We also find out he bandwidth of the AMC is improved by introducing a loss in the material. To validate the AMC, we design a dipole antenna on the AMC and demonstrate a relationship between AMC phase and dipole antenna's operating frequency by investigating the dipole on the AMC with different pairs of ε_r and μ_r.

• Science of Emotion and Sensibility
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• v.20 no.2
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• pp.117-126
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• 2017

In this study, moisture transport characteristics for the woven and knitted fabrics made of 8 kinds of fiber materials using MMT (moisture management tester) were measured and discussed with the Bireck bt MMT and water evaporating rate (WER) measuring methods, which are vertical moisture transport methods. In addition, the drying property by MMT of the eight kinds of specimens was compared and discussed with the results measured by the vertical drying measurement. MMT experimental result which is horizental moisture transport appeared to be similar to the result of the Bireck method, which is the vertical moisture transport experiment. Absortion time measured from drip method of the fabrics made of the bamboo, linen, and cotton/nylon composite fabrics was short and thus they showed best wicking property, which was attributed to the low contact angle on the fabric surface and high porosity of the fabrics due to the staple yarn structure composed of the hydrophilic staple fibers. In drying property of the fabric specimens by MMT, maximum absorption radius of the dry-zone knit and bamboo woven fabrics were the highest and they showed the best drying property, which was a little different result compared with vertical drying measurement method. Half time of the drying rate in the MMT method was highly correlated with the fabric thickness and saturated moisture absortion rate and their regression coefficients were 0.9 and 0.88, respectively. This means that the knitted and woven fabric design technology for retaining good wicking and drying properties of the fabrics with thin fabric thickness is very important for obtaining high functional wear comfort fabrics. In addition, wicking and drying properties of the fabrics made of different fiber materials and with different yarns and fabric structures showed different results according to the measuring methods.

• The Korean Journal of Applied Statistics
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• v.1 no.2
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• pp.34-44
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• 1987

In order to estimate the optimum fertilizer level for rice, a major food crop, the experimental results obtained from the fertilizer trials conducted at 642 experimental sites(farmers' fields) throughout the country for the period from 1976 to 1979 were examined. Since non-significant interactions among fertilizers have been ovserved from the past experiences, only thirteen treatments(combinations of fertilizer levels) for the experiments as given in the Table 1 were chosen such that simple response curves can be fitted with independent variables being N, $P_2O_5, and K_2O$. Weighted combining analysis of variance was also carried out for each type of paddy fields to test the significance of Treatments $\times$ Experimental sites interaction, and highly significant variability in response to treatments among experimental sites in the same type of paddy fields was observed in most types of fields. For the types of paddy fields where the treatments $\times$ experimental sites interaction was not significant, separate response curves for N, $P_2O_5, and K_2O$ were estimated on the basis of the mean yields of rice, and common values of the optimum levels of fertilizers were extimated thereform. When the interaction is significant, response curves were fitted for each experimental sites. The average fertilizer doses estimated for the types of paddy fields based on the individual sites are given in Tables 7-1 and 7-2.

• Journal of the Society of Disaster Information
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• v.14 no.2
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• pp.130-140
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• 2018

Purpose: In this paper, we propose a design technique for the safety characterization grounding in the construction of the photovoltaic power generation complex which can be useful and useful as an alternative power energy source in our society. In other words, we will introduce the application of safety grounding for each application, which can improve and optimize the reliability of the internal grid from the cell module to the electric room in the photovoltaic power generation complex. Method: We analyze the earth resistivity of the soil in the solar power plant and use the computer program (CDEGS) to analyze the contact voltage and stratospheric voltage causing the electric shock, and propose the calculation and calculation method of the safety ground. In addition, we will discuss the importance of semi-permanent ground electrode selection in consideration of soil environment. Results: We could obtain the maximum and minimum value of ground resistivity for each of the three areas of the data measured by the Wenner 4 - electrode method. The measured data was substituted into the basic equation and calculated with a MATLAB computer program. That is, it can be determined that the thickness of the minimum resistance value is the most favorable soil environment for installing the ground electrode. Conclusion: Through this study, we propose a grounding system design method that can suppress the potential rise on the ground surface in the inner grid of solar power plant according to each case. However, the development of smart devices capable of accumulating big data and a monitoring system capable of real-time monitoring of seismic changes in earth resistances and grounding systems should be further studied.

• Cartoon and Animation Studies
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• s.42
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• pp.81-104
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• 2016

was released in South Korea in 2002 with more than 2million audiences and had been appraised as a successful and sensational work. The work let the audiences highly evoke interest and curiosity through offering magnificent sceneries, weird and funny creatures and stimulating imagination, before having no idea about the work producted by Miyajaki Hayao, one of the greatest directors. Well-concentrated his works seem to be easy to understand but have a variety of meanings in very different ways. Expending the range of analysis of his works, for example, from its technical to cultural and philosophical etc. has an enormous amount of value of diversity such as a ray of light passing through a prism. For this reason, has been studied in many different views. This paper will analyse this animation in respect of ideas of eastern as well as western to show differences from former papers. The ideas of eastern and western seem to be not in a line, but this study will suggest that the two different ideas are not different, actually. Through plural analysis of , ask questions about what life is and what the direction is.

• Resources Recycling
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• v.27 no.2
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• pp.24-31
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• 2018

In this study, waste ITO target is dissolved into hydrochloric acid to generate a complex indium-tin chloride solution. Nano sized ITO powder with an average particle size below 30 nm are generated from these raw material solutions by spray pyrolysis process. Also, in this study, thermodynamic equations for the formation of indium-tin oxide (ITO) are established. As the reaction temperature increased from $800^{\circ}C$ to $900^{\circ}C$, the proportion and size of the spherical droplet shape in which nano sized particles aggregated gradually decreased, and the surface structure gradually became densified. When the reaction temperature was $800^{\circ}C$, the average particle size of the generated powder was about 20 nm, and no significant sintering was observed. At a reaction temperature of $900^{\circ}C$, the split of the droplet was more severe than at $800^{\circ}C$, and the rate of maintenance of the initial atomized droplet shape decreased sharply. The average particle size of the powder formed was about 25 nm. The ITO particles were composed of single solid crystals, regardless of reaction temperature. XRD analysis showed that only the ITO phase was formed. Remarkably, the specific surface area decreased by about 30% as the reaction temperature increased from $800^{\circ}C$ to $900^{\circ}C$.

• Analytical Science and Technology
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• v.17 no.6
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• pp.470-475
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• 2004

The mercury film thin layer flow cell (MFTLFC) which yielded the highest sensitivity for the electrochemical reduction of doxorubicin was constructed by coating the glassy carbon working electrode (GCE; $A=0.208cm^2$) with $5{\mu}L$ of HgO coating solution (0.5% HgO + 0.25% polystyrene/cyclohexanone) and subsequently followed by applying a potential of -0.40 V for 300 sec in the flow stream of an acetate buffer of pH 4.5. The voltammogram of doxorubicin reached the diffusion current plateau at -0.53 V vs. a Ag/AgCl (3 M NaCl) in the MFTLFC. The diffusion current (Id) of doxorubicin at the MFTLFC was 1.7 times greater than the Id obtained at the TLFC employing a bare glassy carbon working electrode. When the peak areas (electric charge) were plotted vs. concentrations of standard anthracyclines, the calibration factors of doxorubicin and daunorubicin were $1.12{\times}10^8{\mu}C/M$ (coefficient of determination; $R^2$: 0.969) and $0.98{\times}10^8{\mu}C/M$> ($R^2$: 0.999), respectively in the concentration range between $1.0{\times}10^{-8}M$ and $1.0{\times}10^{-6}M$.

• International Journal of Highway Engineering
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• v.1 no.1
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• pp.107-119
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• 1999

The joints in the jointed concrete pavement provide a control against transverse or longitudinal cracking at slab, which may be caused by temperature or moisture variation during or after hydration. Without control of cracking, random cracks cause more serious distresses and result in structural or functional failure of pavement system. However, joints nay cause distresses due to its inherent weakness in structural integrity. Thus, the evaluation at joint is very important. and the joint-related distresses should be evaluated reasonably for economic rehabilitation. The purpose of this paper was to develop an evaluation system at joints of jointed concrete pavement using finite element analysis program, ILLI-SLAB, and nondestructive testing device. FWD. To develop an evaluation system for JCP, a sensitivity analysis was performed using ILLI-SLAB program with a selected variables which might affect fairly to on the performance of transverse joints. The most significant variables were selected from precise analysis. An evaluation charts were made for jointed concrete pavement by adopting the field FWD data. It was concluded that the variables which most significantly affect to pavement deflections are the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G), and limiting criteria on the performance of joints at JCP are 300pci. 500,000 lb/in. respectively. Using these variables and FWD test, a charts of load transfer ratio versus surface deflection at joints were made in order to evaluate the performance of JCP. Practically, Chungbu highway was evaluated by these evaluation charts and FWD field data for jointed concrete pavement. For Chungbu highway, only one joint showed smaller value than limiting criterion of the modulus of dowel/concrete interaction(G). The rest joints showed larger values than limiting criteria of the modulus of subgrade reaction(K) and the modulus of dowel/concrete interaction(G).

• Conservation Science in Museum
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• v.14
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• pp.91-113
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• 2013

Cheongpung Buwongun Kim Wu-myeong's Funeral Bier, an important folklore cultural property No.120, possessed by Chuncheon National Museum was donated in 2002 (by Kim Seonggu). It consists of a bier, yoyeo(腰輿), myeongjeongdae(銘旌臺), and manjangdae(輓章臺). It has a high value as the oldest royal bier. The bier which had a resting time in the storage for special exhibition of "The great cultural treasure of Gangwon province" was inspected in September 2012 and colored pigment layer of the wooden part had the risk of peeling off and surface damage of the textile was serious. Therefore, conservation treatment was conducted. In addition, knots and susiks(垂飾) were severely damaged and their exhibition was impossible. Therefore, a reproduction to replace them through a close investigation was made. All parts of the funeral bier were in separation except for the basic furniture. Conservation was made by dividing the parts into wooden parts and textile parts. Yoyeo was reinforced after disassembling bujae from it and then was reassembled. Paraloid B-72 2 wt% (in ethyle acetate), acrylic resin, was applied to the wooden part of the bier in order to reinforce the colored pigment layer with the addition of sodium alginate 2 wt%(in stilled water) and glue 4 wt%(in stilled water). The pollutants on the surface of the textile part were removed (vacuuming) and its creases were smoothed out (steaming). Fat-soluble pollutants were removed using an nonionic surfactant(Saponin, concentration at 0.25 to 0.5 g/𝑙, in de-ionized water). After the disassembly of the yoyeo from the broken wooden, it was bonded with glue (3 wt% for the first gluing, 35 wt% for gluing), and pine wood was used to restore missing parts. In the process of connecting Wongak(雲角), the original metal hinge and nails were reused to complete the assembly.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.246-254
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• 2022

Domestic facility agriculture grows rapidly, such as modernization and large-scale. And the production scale increases significantly compared to the area, accounting for about 60% of the total agricultural production. Greenhouses require energy input to create an appropriate environment for stable mass production throughout the year, but the energy load per unit area is large because of low insulation properties. Through the rooftop greenhouse, one of the types of urban agriculture, energy that is not discarded or utilized in the building can be used in the rooftop greenhouse. And the cooling and heating load of the building can be reduced through optimal greenhouse operation. Dynamic energy analysis for various environmental conditions should be preceded for efficient operation of rooftop greenhouses, and about 40% of the solar energy introduced in the greenhouse is energy exchange for crops, so it should be considered essential. A major analysis is needed for each sensible heat and latent heat load by leaf surface temperature and evapotranspiration, dominant in energy flow. Therefore, an experiment was conducted in a rooftop greenhouse located at the Korea Institute of Machinery and Materials to analyze the energy exchange according to the growth stage of crops. A micro-meteorological and nutrient solution environment and growth survey were conducted around the crops. Finally, a regression model of leaf temperature and evapotranspiration according to the growth stage of leafy vegetables was developed, and using this, the dynamic energy model of the rooftop greenhouse considering heat transfer between crops and the surrounding air can be analyzed.