• Proceedings of the KSRS Conference
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• v.1
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• pp.520-523
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• 2006

Whereas it is well known that the surface roughness parameters, the RMS height and the correlation length, of a natural soil surface are underestimated with a short surface profile, it is not clear how much the underestimated surface parameters affect the backscattering coefficients of the surface for various incidence angles and polarizations. The backscattering coefficients of simulated and measured surface profiles are computed using the integral equation method (IEM) and analyzed in this paper to answer this question. It is shown that the RMS error of the backscattering coefficients between 5-m- and 1-m-long measured surface profiles is 1.7 dB for vv-polarization and 0.5 dB for hh-polarization at a medium range of incidence angle ($15^{\circ}{\leq}{\theta}{\leq}70^{\circ}$), while the surface roughness parameters are significantly reduced; from 2.4 cm to 1.5 cm for the RMS height s and from 35.1 cm to 10.0 cm for the autocorrelation length l. This result is verified with numerous simulations with various roughness conditions and various wavelengths.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.781-785
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• 1989

In the field of control technology, too, it is about time that the students should free themseleves from the paradigm of Newtonian mechanics. Otherwise, they might fail to grasp the essence of control. Now, let us consider the essence of control. Control consists of manipulating a particular object, matter, energy of environment on the basis of certain medium information. (measurement data, force, etc.) So, we shall look into the methods of manipulation. Here, we consider natural control, constraining control, and hybrid control as basic methods of manipulation. In this paper, we would like to put forward the daring proposal that it's called a Holon-type hybrid control system. It is intended to control a plat with complicated or unknown characteristics where a conventional control theory is not easy to apply. A prototype system has been developed and applied to a real plant. The control system is a multi-layer system. Each layer includes different control input. The important features of the system are as follows: 1) Each layer behaves autonomously and also cooperates with each other to optimize the whole plant. 2) The controller optimizes a plant without mathematical models when these models are not easy to obtain.

• Journal of architectural history
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• v.21 no.6
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• pp.35-44
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• 2012

This paper aimed at investigating into the origin and meaning of the Japanese architect Terunobu Fujimori's 'piercing column', and drew a conclusion as follows. First, the piercing column that made its first appearance in his architect debut work Jinchokan Moriya Historical Museum (1991) was conceived unexpectedly from pencil lines on a sketch that went through over the building's roof. And the tree-like natural treatment of the column's surface was influenced by Takamasa Yoshizaka's description of a Mongolian mud-house. Second, most of piercing columns in his later works have nothing to do with a structural role as in Jinchokan, but were designed for a visual effect and as a symbolic gesture. Again, they allude to a tree in nature through a roughly peeling treatment of the surface. Third, considering his ideas in History of Humankind and Architecture (2005), his column could be related to a universal origin of architecture and a symbol of the sun-god faith, and in particular to independent columns of Japanese Shito shrines, such as 'Onbashira' in Suwa and 'Iwanebashira' in Izumo. That is to say, the Fujimori column is a medium that implies the animistic nature-faith of Japan. Nevertheless, Fujimori's naturalism hints at a disquieting quality through an intentional artificiality and a provocative conflict between structure and finish of a building, which might be one aspect of the modern condition, 'uncanny'.

• Korean Journal of Human Ecology
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• v.9 no.3
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• pp.37-45
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• 2006

The purpose of this study was university student's preference for own house in future according to gender. This was the investigation of which 512 university students in Jeollabukdo province. In this statistical analysis, SPSS 11.5 program was utilized to calculate percentage, mean and standard deviation. Also, these materials were verified by factor analysis, t-test and $x^2$-test. The results of this study were as follows: The university students' future housing environment preferences has been appeared to be higher in the environmental equipment and the natural scenery. In the case of the gender variables was appeared to be higher for female than male students. The future housing area most of the university students wanted the medium city or over, $25{\sim}33\;p'y{\breve{o}}ng$ apartment, 3 bed rooms, 2 bathroom. In case most students have a yard in their future house, they'd like to grow lawn and trees. Also, they wanted to live in a short distance with their future parents-in-law. Therefore, It was desirable that make a plan based on the results of this study future-residing for the new generation.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.39-44
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• 2009

Geothermal energy is the heat contained in the earth and its internal fluids. Geothermal energy is stored as sensible or latent heat. Supplied by both internal and external sources, it represents a vast supply which is only started to be tapped for generation of electric power. In general, this is natural dry or wet medium to high enthalpy steam at temperatures above $150^{\circ}C$. For some time, binary systems employing substances with a lower boiling point than water in a secondary circuit have been used to generate vapor for driving turbines at a lower temperature level. The utilization of binary plants and the possibility of production from enhanced geothermal systems can expand its availability on a worldwide basis. The geothermal electricity installed capacity is approaching the 10,000GW threshold. Geothermal energy is not present everywhere, but its baseload capability is a very important factor for its success.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.17-22
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• 2006

Shear modulus is directly linked to material's stiffness and is one of the most critical engineering parameters. Seismically, shear-wave velocity (Vs) is its best indicator. Although methods like refraction, down-hole, and cross-hole shear-wave surveys can be used, they are generally known to be tougher than any other seismic methods in field operation, data analysis, and overall cost. On the other hand, surface waves, commonly known as ground roll, are always generated in all seismic surveys with the strongest energy, and their propagation velocities are mainly determined by Vs of the medium. Furthermore, sampling depth of a particular frequency component of surface waves is in direct proportion to its wavelength and this property makes the surface wave velocity frequency dependent, i.e., dispersive. The multichannel analysis of surface waves (MASW) method tries to utilize this dispersion property of surface waves for the purpose of Vs profiling in 1-D (depth) or 2-D (depth and surface location) format. The active MASW method generates surface waves actively by using an impact source like sledgehammer, whereas the passive method utilizes those generated passively by cultural (e.g., traffic) or natural (e.g., thunder and tidal motion) activities. Investigation depth is usually shallower than 30 m with the active method, whereas it can reach a few hundred meters with the passive method. Overall procedures with both methods are briefly described.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1516-1523
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• 2004

The purpose of this study were to analyze the effect of weft knit structural characteristics on the subjective texture and sensibility. For this, the material was knitted into 8 kinds of weft plain knit fabrics with four kinds of fiber components such as wool, acryl, rayon, and nylon, 3 steps of densities and 3 steps of twist numbers to ply two yarns. The data were analyzed by factor analysis, ANOVA and multidimensional scaling. From factor analysis, subjective textures were categorized as 'bulk/resilience', 'surface/density' and 'soft/drape', and subjective sensibilities were categorized as 'natural/comfortable', 'feminine/elegance' and 'stable/neat' Among the knit structural characteristics, the component of fibers and the density of fabrics were the important factors to give variations in texture and sensibility : In comparison with wool knit of medium density, the knit fabrics of other components and different densities each showed a unique texture and sensibility. But twist number to ply two yams had a few influence on subjective properties. As a result of MDS analysis, the texture and sensibility of plain weft knit fabrics was classified as 'thin-full', 'hard-soft', 'young-old' and 'warm-cool'.

• Animal Systematics, Evolution and Diversity
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• v.27 no.2
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• pp.151-158
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• 2011

Fish community structure in the Pyeongchanggang River was investigated from April to November 2009. About 900 individuals representing 24 species from eight families at six sites in the Pyeongchanggang River were collected. It was similar to the 2001's survey and it was less than 2006's survey. The Korean endemic species, Zacco koreanus was the most abundant, whereas subdominant species were native species, such as Pungtungia herzi, Zacco platypus, Rhynchocypris kumgangensis and Rhynchocypris oxycephalus. Three endangered species were collected at the sampling area, Acheilognathus signifier (relative abundance [RA] 0.9%), Pseudopungtungia tenuicorpa (RA 1.4%), and Cottus koreanus (RA 3.6%). One natural monument species, Hemibarbus mylodon, was included. According to the analysis of ecological indicator characteristics, the relative proportion of tolerant species was 6.3% (57 individuals), whereas the proportion of sensitive species was 65.9% (593 individuals). Species evenness, richness and diversity indices decreased gradually through the month from April to November during the study. Community indices in Pyeongchanggang River showed a high evenness index (J'>0.6), a low level of species richness (R<3.5) and a medium level of diversity (1.5

• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.441-448
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• 2017

Microcystis aeruginosa (M. aeruginosa) is a cyanobacterium species that can form harmful algal blooms in freshwater bodies worldwide. The use of Artemisia asiatica extracts to control M. aeruginosa inhibition will be environmentally friendly and promising. Artemisia asiatica extracts removed successfully upto 88% of M. aeruginosa pH 8 at $25^{\circ}C$ of temperature. These results was indicated that the amount of 2.24 g/L Artemisia asiatica extracts was removed 1g dryweight/L of M. aeruginosa. The kinetic data showed substrate inhibition kinetics and maximum growth rate was obtained when the M. aeruginosa was grown in medium containing 2.5 g/L of initial concentration of Artemisia asiatica extracts. In the various growth control models, Luong model showed the highest correlation coefficient of 0.9916. Therefore, the Luong model was the most suitable control model for the growth control of M. aruginosa using Artemisia asiatica extracts. In conclusion, the growth control of M. aruginosa using Artemisia asiatica extracts can be applied in the field without controlling the temperature and pH of rivers and streams, and it is possible to control the growth of M. aruginosa efficiently in a short time. The natural extract, Artemisia asiatica extracts, can be a promising inhibition due to its high efficiency and low dose requirements.

• Journal of The Korean Astronomical Society
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• v.51 no.2
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• pp.37-48
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• 2018

Massive stars blow powerful stellar winds throughout their evolutionary stages from the main sequence to Wolf-Rayet phases. The amount of mechanical energy deposited in the interstellar medium by the wind from a massive star can be comparable to the explosion energy of a core-collapse supernova that detonates at the end of its life. In this study, we estimate the kinetic energy deposition by massive stars in our Galaxy by considering the integrated Galactic initial mass function and modeling the stellar wind luminosity. The mass loss rate and terminal velocity of stellar winds during the main sequence, red supergiant, and Wolf-Rayet stages are estimated by adopting theoretical calculations and observational data published in the literature. We find that the total stellar wind luminosity due to all massive stars in the Galaxy is about ${\mathcal{L}}_w{\approx}1.1{\times}10^{41}erg\;s^{-1}$, which is about 1/4 of the power of supernova explosions, ${\mathcal{L}}_{SN}{\approx}4.8{\times}10^{41}erg\;s^{-1}$. If we assume that ~ 1 - 10 % of the wind luminosity could be converted to Galactic cosmic rays (GCRs) through collisonless shocks such as termination shocks in stellar bubbles and superbubbles, colliding-wind shocks in binaries, and bow-shocks of massive runaway stars, stellar winds might be expected to make a significant contribution to GCR production, though lower than that of supernova remnants.