• 한국세라믹학회지
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• 제49권5호
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• pp.399-403
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• 2012

SnO thin films were fabricated by rf reactive sputtering on borosilicate substrates with an Sn target and Ar/$O_2$ gas mixture. The effect of rf power on the structural, electrical, and optical properties of SnO thin films was investigated with XRD, AFM, SEM, Hall effect measurements, and UV-Vis spectrometer. As a plasma power increased the crystallinity with a preferred orientation of SnO thin films was improved and the grain size slightly increased. However the grains were coalesced and excessively irregular in shape. The electrical conductivity of SnO thin films demonstrated a relatively low p-type conductivity of 0.024 $(Wcm)^{-1}$ at a higher power condition. Lastly, SnO thin films had poor optical transmittance in the visible range as a plasma power increased.

• 대한기계학회논문집A
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• 제26권6호
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• pp.1120-1126
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• 2002

Machining characteristics of tool steels manufactured by electro slag casting process has been investigated in this study. For the estimation of machinability, turning and drilling tests are carried out. The chip shapes at various velocities are investigated for the comparison of turning workabilities of tool steels because the chip shapes reflect characteristics of cutting resistance. In case of drilling test, feed motor currents measured by a hall sensor are used as a measure for the drilling resistance. The machining characteristics of the tool steels are strongly correlated with tensile properties, such as tensile strength, hardness, and ductility. In case of turning workability, it was found to be favoured by the higher tensile strength, while the opposite is true far the drilling workability. The electro-slag casted materials show better turning workability in the viewpoint of chip shapes and, the quenching-tempered electro-slag casted material has relatively better drilling machinability than that of the annealed one.

• 교육시설
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• 제11권1호
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• pp.39-46
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• 2004

The objective of this study is to propose the architectural basic data for the planning of kindergarten attached to the elementary school. For this study, we selected and investigated 23kindergartens in Gwangju city. The results of this study are as follows. 1) The elementary school in separated style had the advantage of securing educational space and reducing interference with students of elementary school. But it had the problem in using the facilities of elementary school. So we have to consider the kindergarten to be located near by dinning room, multi-purpose hall. 2) Concentrating the entrance, it makes the inside and outside space use easily. For the actual use, we have to establish facilities for convenience in outer-space. 3) For each room, we suggest guides as follow. The classroom and the playroom have to be combined for flexibility and supervision. In the planning of toilet, it must have sliding door for confirm the inside situation and reasonable height partition to consider the student's body-size. The shape of teacher's room must be open-type for supervising children but protect the entry of children. There is consideration for the material room and the sleeping room for all-day-long class.

• 한국전기전자재료학회논문지
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• 제15권3호
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• pp.220-226
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• 2002

Amorphous $Sb_{2-x}Bi_xTe_3$ (x = 0.0, 0.5 and 1.0) thin films were prepared by vacuum evaporation. The resistivity of 7he films decreases from 1.4{\times}10^{-2}$ to $8.84{\times}10^{-5}\Omega cm$ and the type of conductivity changes from p to n with the increase of the x value of the films. D.C. conduction studies on these films ate performed at various electric fields in the temperature range of 303-403 K. At low electric fields, two types of conduction mechanisms, i.e. the variable range hopping and the phonon assisted hopping are found to be responsible for the conduction, depending upon the temperature. The activation energy decreases from 0.082 to 0.076 eV in the temperature range of 303-363 K and from 0.47-0.456 eV in the second range of 363-403 K, indicating the shift of the Fermi level towards the conduction band edge and hence the change of the conduction from P to n type with the increase of the Bi concentration. Poole-Frankel emission dominates at high fields. The shape of the potential well of the localized centre is deduced and the mean free path of the charge carriers is also calculated.

• 한국조경학회지
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• 제27권3호
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• pp.18-31
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• 1999

The research deals with external space Seowon(lecture hall) dedicated to education and memorial rises in Sangju area of Choson Dynasty. Characteristics of Seowon as follow; 1. Seowon of Sangju area were built from the middle of 17C to the beginning of 18C. Ideological background of building functioning were grafted into the belief in the three God governing Childbirth, the theory of feng-shui(wind-and water-magic) which is in close connection with the principles of yin and yang, and confucianism and the philosophy of lao-tze and chung-tze. The formation of space were horizontally arrangement and vertical arrangement as the first-learning and then-ancestor shrine of Youngnam provinces. 2. Background and factors of site selection were applied geographical feature, tried to connect owner home town. 3. The shape of path of flow were simple of vertical and curved composition, were continued, were stabilized through composition of human scale's space by reasonable internal. A case of Sangju area, D/H ratio of the front area of buildings and courts was as follows. D/H=1>Hyangkyo> houses on the river>temples>lecture halls. D/H ratio ot the backside areas is as follows. D/H=1>Hyangkyo>houses on the river>lecture halls. 4. Inner garden were planted deciduous than evergreen trees with Lagerstroemia indica. Enclosed dominant trees were planted by Pinus densiflora, Querces seuata.construct GEM strain, and examined for the expression and functional stability in microcosms.

• 전자공학회논문지D
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• 제34D권7호
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• pp.56-61
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• 1997

I $n_{0.53}$G $a_{0.47}$As/I $n_{0.52}$A $l_{0.48}$As pseudomorphic high electron mobility transistor (P-HEMT) structures were grown on semi-insulating InP substrates by molecular beam epitzxy method. The hall effect measuremetn was used to measure the electrical properties and the photoluminescence (PL) measurement was used to measure the electrical properties and the photoluminescence(PL) measurement for optical propety. By the cross-sectional transmission electron microscopy (XTEM) investigation of the V and X shape defects including slip with angle of 60.deg. C and 120.deg. C to surface in the sampel, the defects formation mecahnism in the I $n_{0.52}$A $l_{0.48}$As epilayers on InP substrates could be explained with the different thermal expansion coefficients between I $n_{0.52}$A $l_{0.48}$As epilayers and InP substrate.d InP substrate.

• 패션비즈니스
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• 제7권6호
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• pp.10-20
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• 2003

The object of this research is to develop the designs with aesthetics and function for making the uniforms of specialty restaurants of Korean dishes in pursuit of the image of excellent dignity and its result is as follows: As for designs, this research chose the traditional image as the basic concept and made visual Korean lines, colors, and patterns. As for lines, it made visual the curve of the eaves, the straight line of polls, and the fret of windows and doors represented in architecture and applied them, as for color tones, it chose traditional 'Obangsaek', five direction colors. As for the patterns, it symbolized 4 trigrams( Geon, Gon, Gam, and Yi), the cloud pattern, also it tried to get the formative beauty from traditional patchwork wrapping cloth and windows and doors. The expectant effects on the design of Uniform are as follows: First, it offered basic clothes for male and female employees working in the hall and suggested two kinds of skirt and pants for the latter. It tried to find out both the function of pants and the female beauty of skirts by wrapping on pants to eliminate the feeling of rejection towards the style of them, the use of which have been recognized for man only in spite of many merits of them. Second, it sought for the characteristics of shape on collar, breast-tie, and fold etc. of Korean clothes and designed clothes according to each employee's role and finally emphasized their traditional aesthetics.

• 국제초고층학회논문집
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• 제9권3호
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• pp.283-300
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• 2020

The Lakhta Center is a Multifunction Complex Development (MFCD) consisting of 1) an 86 story office tower rising 462 m above the ground to provide high-end offices for Gazprom Neft and Gazprom Group affiliates 2) a Multi-Function Building (MFB) that includes, a scientific/educational center, a sport center, a children's technopark, a planetarium, a multi-transformable hall, an exhibition center, shops, restaurants, and other public facilities 3) a Stylobate 4) "The Arch, which forms the main entrance to the tower, restaurants, and cafes 5) underground parking and 6) a wide range of large public plazas. While each of the MFCD buildings is technically challenging in its own right, the focus of the paper is to present the development and integration of the structural and foundation systems of the bowed, tapered, and twisted shape of the tower into the fabric of the tallest Tower in Europe.

• 한국재료학회지
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• 제30권8호
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• pp.399-405
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• 2020

In the present investigation we show the effect of Al doping on the length, size, shape, morphology, and sensing property of ZnO nanorods. Effect of Al doping ultimately leads to tuning of electrical and optical properties of ZnO nanorods. Undoped and Al-doped well aligned ZnO nanorods are grown on sputtered ZnO/SiO₂/Si (100) pre-grown seed layer substrates by hydrothermal method. The molar ratio of dopant (aluminium nitrate) in the solution, [Al/Zn], is varied from 0.1 % to 3 %. To extract structural and microstructural information we employ field emission scanning electron microscopy and X-ray diffraction techniques. The prepared ZnO nanorods show preferred orientation of ZnO <0001> and are well aligned vertically. The effects of Al doping on the electrical and optical properties are observed by Hall measurement and photoluminescence spectroscopy, respectively, at room temperature. We observe that the diameter and resistivity of the nanorods reach their lowest levels, the carrier concentration becomes high, and emission peak tends to approach the band edge emission of ZnO around 0.5% of Al doping. Sensing behavior of the grown ZnO nanorod samples is tested for H₂ gas. The 0.5 mol% Al-doped sample shows highest sensitivity values of ~ 60 % at 250 ℃ and ~ 50 % at 220 ℃.

• 대한조선학회논문집
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• 제48권2호
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• pp.183-187
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• 2011

As larger the commercial vessel is, and rougher the marine environment becomes nowadays, drag embedment type anchor (DEA) of more stable performance and higher holding power is requested to be applied on the vessel. But, the performance of DEA has not become well known to academy and industries so far, that the basic study of DEA performance and holding force for the development of new DEA of higher performance is insufficient that required. In this paper, three types of same holding category DEA model (HALL, AC-14, POOL-N, scale 1/10), which are generally applied on the commercial vessel nowadays, were tested by being horizontally dragged on the test tank, on which sand was being floored with sufficient depth, and measured the holding force of each anchor simultaneously using load cell and D/A converter. With the test results, the embedding motion was analyzed to have three different stages and the holding force of each anchor was analyzed with respect to the anchor geometry, such as shape and weight of each type of anchors, and final embedding depth.