• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.916-919
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• 2004

This paper studied about the (100) orientation of PZT thin films coated on the LNO electrode using a different thermal annealing. The thermal annealing method is divided into two things. The one is the method transferring heat to only the lower substrate and another is transferring heat to all directions. Orientation factor of PZT in the method of transferring heat to only the lower substrate was F=99% in the thermal annealing of the LNO. Orientation factor of PZT was F=67% in the method of transferring heat to all directions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.2
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• pp.176-180
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• 2006

[ $(Na_{0.5}Bi_{0.5})TiO_3$ ][NBT] thin films were prepared on a highly (100) oriented $LaNiO_3[LNO]$ by sol-gel process. X-ray diffraction patterns of the NBT films annealed above $600^{\circ}C$ for 5 minutes have confirmed a highly (100) oriented growth and pseudocubic structure (a=3.884${\AA}$). The (l00) orientation factor increased from 90 to $99\%$ with increasing soaking time from 5 to 60 minutes at $600^{\circ}C$. The NBT films ($600^{\circ}C$/5 min,) have a flat and dense microstructure with large columnar grains, and their grain size are about 44 nm. The Au/NBT/LNO/Si hetero structure sample show a ferroelectric properties.

• Journal of the Korean Home Economics Association
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• v.40 no.2
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• pp.87-100
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• 2002

The purpose of this study was to investigate the demographics and general clothing buying behavior according to clothing shopping orientation of female workers. A questionnaire was developed to measure clothing shopping orientation, fashion information sources, stores selection criteria, clothing purchasing frequency of a year, purchasing expenditure of clothing, the demographics. The questionnaire was administered to 775 female teacher in Chonnam. The data was analyzed using percentage, frequency, mean, factor analysis, Cluster Analysis, $\chi^2$-_test and ANOVA, Duncan test. The results of the study were as follows: 1. The female teachers were classified into four groups by the cluster analysis; indifferent shopping group, rational shopping group, conspicuous shopping group, recreational shopping group. 2. In the case of fashion information sources, significant differences were found according to shopping orientation subdivision in mass media information, information by consumer, information by marketer. 3. The stores selection criteria were significantly different depending on shopping orientation subdivision in goods and atmosphere of shop, promotion, convenience of shop's location. 4. The clothing purchasing frequency of a year were significantly different depending on shopping orientation subdivision. 5. The significant differences were found according to shopping orientation subdivision in purchasing expenditure of clothing. 7. In the demographic characteristics, significant differences were found according to shopping orientation subdivision in age, marriage, the length of one's work, income.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.859-865
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• 2004

LaNiO$_3$(LNO) thin films on (100) Si substrates are prepared by sol-gel method on heat treatment conditions, such as heat transfer direction, pyrolysis and annealing process, and annealing temperatures and times. The effect of heat treatment conditions on the (100) orientations, structures and resistances of the thin films are investigated by XRD, SEM(FESEM), and a lout probe method. Highly (100) orientation factor(0.97), a pseudocubic crystalline structure with a dense and uniform microstructure could be formed by the following conditions： 1) the heat transfer direction is from Si substrate to LNO, 2) the pyrolysis and annealing process are alternated, 3) the annealing temperature is $650^{\circ}C$ and 4) the annealing times is 3 minutes. The sheet resistance of thin films decreased with increasing of a annealing temperature and time, and a number of coating.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.905-909
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• 2007

Crystalline and micro-structural characteristics of ZnO thin films which were deposited on p-Si(100) with cooling naturally down of pre-heated substrate during RF magnetron sputter deposition, were investigated by XRD and SEM in this paper. The film which was prepared on the substrate which was pre-heated to $400^{\circ}C$ before deposition and then cooled naturally down during deposition, showed the most outstanding c-axis preferred orientation. The ZnO thin film having the best crystalline result were applied to SMR type FBAR device and resonance properties of the device were investigated by network analyzer. It showed that resonance frequency was 2.05 GHz, return loss was -30.64 dB, quality factor was 3169 and electromechanical coupling factor was 0.4 %. This deposition method would be very useful for application of surface acoustic wave filter or film bulk acoustic wave resonator.

• Solar Energy
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• v.8 no.1
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• pp.41-48
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• 1988

Heterojunction solar cells of $n-Cd_{1-x}Zn_xS/p-Si$ were fabricated by solution growth technique. The crystal structure, spectral response, surface morphology, and I-V characteristics of the $n-Cd_{1-x}Zn_xS/p-Si$ heterojunction solar cells were studied. The $Cd_{1-x}Zn_xS$ layer deposited on a silicon substrate (111) were found to be a cubic structure with the crystal orientation (111), (220) of the CdS and to be a hexagonal structure with crystal orientation (100) of the ZnS. The open-circuit voltage, short-circuit current, fill factor, and conversion efficiency of $n-Cd_{1-x}Zn_xS/p-Si$ heterojunction solar cell under $100mW/cm^2$ illumination were found to be 0.43V, 38mA. 0.76, and 12.4%, respectively.

• Progress in Superconductivity
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• v.12 no.1
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• pp.57-61
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• 2010

We have developed a whole-head MEG system for basic brain research and clinical application. The sensor system consists of a 152 SQUID gradiometer array oriented and located in a suitable way to cover a whole head of the human. The system measures magnetic fields generated by neuronal currents in the brain to get information on the brain activities. For this purpose, the field sensitivity determined by the position, orientation and geometry of the pickup coil as well as amplification factor of the electronic circuits should be known precisely. However, the position and orientation of the pickup coil might be changed from the designed specifications during cool down of the dewar and it is necessary to characterize the field sensitivity. In this study, we made calibration systems to determine the actual position and orientation of the 152 pickup coils and compared the localization results of the N100m source in the auditory cortex.

• Journal of the Korean Society of Costume
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• v.55 no.1 s.91
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• pp.86-100
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• 2005

The purpose of this study was to investigate lifestyle of male college students and their preference of casual wear style. A questionnaire consisted of 60 lifestyle items, 1 casual wear style-preference question and demographic variables was developed. Data were collected from questionnaires distributed to male college students of 7 universities located in the Daegu${\cdot}$Gyeongbuk area during August 2003. After eliminating incomplete questionnaires, 303 were analyzed by descriptive statistics, factor analysis, cluster analysis, one-way ANOVA, and $x^2-test$. As a result of factor analysis on lifestyle items, 8 factors were determined: consumption and fashion orientation, future preparation, social concern, a wide range of thought and experience, health orientation, independent spirit, masculinity, and family orientation. 4 groups were identified on the basis of these 8 factors and named as active pragmatic group, liberal empirical group, prospective self-supporting group, and social accommodative group. Their component ratio were $30.2\%,\;33.2\%,\;19.6\%,\;and\;16.9\%$ respectively. The most preferred casual wear style by male college students was determined as basic casual wear, followed by adult casual wear, fashionable casual wear, and sporty casual wear. Other than the most preferred style, basic casual wear, by every group, the preference of casual wear styles differed among 4 lifestyle groups.

• Tunnel and Underground Space
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• v.25 no.4
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• pp.341-358
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• 2015

This study analyzes the relationship between parameters of the discontinuity in Discrete Fracture Network model such as fracture intensity, fracture orientation, fracture size, fracture shape etc. In this paper, FracMan code was used to model and analyze 3D DFN. A sensitivity analysis was performed in order to analyze the relationship between linear fracture intensity measure ($P_{10}$) and parameters of the discontinuity in $100m{\times}100m{\times}100m$ model area. As a result the sensitivity analysis showed that key parameters affecting fracture intensity are fracture orientation (Trend / Plunge). Conversion factor($C_{13}$) for $P_{10}$, to calculate volumetric fracture intensity measure ($P_{32}$), is derived in case of vertical well and horizontal well when trend is $10^{\circ}$, $30^{\circ}$, $60^{\circ}$, $90^{\circ}$, $120^{\circ}$, $150^{\circ}$, $180^{\circ}$ (7cases) and plunge is $5^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$, $85^{\circ}$ (7cases). It is expected that this paper can be used effectively for modeling and understanding DFN model.

• Steel and Composite Structures
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• v.15 no.2
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• pp.131-150
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• 2013

This paper presents the experimental results of axially loaded stub columns of slender steel hollow square section (SHS) strengthened with carbon fiber reinforced polymers (CFRP) sheets. 9 specimens were fabricated and the main parameters were: width-thickness ratio (b/t), the number of CFRP ply, and the CFRP sheet orientation. From the tests, it was observed that two sides would typically buckle outward and the other two sides would buckle inward. A maximum increase of 33% was achieved in axial-load capacity when 3 layers of CFRP were used to wrap HSS columns of b/t = 100 transversely. Also, stiffness and ductility index (DI) were compared between un-retrofitted specimens and retrofitted specimens. Finally, it was shown that the application of CFRP to slender sections delays local buckling and subsequently results in significant increases in elastic buckling stress. In the last section, a prediction formula of the ultimate strength developed using the experimental results is presented.