• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.6
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• pp.297-303
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• 2003

Mn-Ni-Co type thin films were prepared at various conditions by a rf magnetron sputtering system. At the condition. or substrate temperature of $300^{\circ}C$ and $Ar/O_2$= 10/0, a cubic spinel phase was obtained. When oxygen was included in process gas, a cubic spinel phase was not formed even after the thermal annealing at $900^{\circ}C$. The thermistor thin film had no other elements except Mn, Ni and Co. The infrared reflection spectra of the thermistor thin films showed that the films had somewhat high reflectance for incoming infrared ray with some angle. The etch rate of the thermistor thin films was about 63nm/min at a condition of DI water : $HNO_3$: HCl = 60 : 30 : 10 vol%. The B constant and temperature coefficient of resistance of the thermistor thin films were 3500 K and -3.95 %/K, respectively. The voltage responsivity of the thermistor thin film infrared sensor was 108.5 V/W and its noise equivalent power and specific detectivity were $5.1\times 10^{-7}$ W/$Hz^{-1/2}$ and $0.2\times 10^6$cm $Hz^{1/2}$/W, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.225-229
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• 2015

This study was performed to investigate crystal structure of cubic spinel-type monophase oxide composed of the Mn-Co-Ni ternary system. Starting material was prepared by mixing Mn, Co, Ni oxides then evaporation to dryness. The XRD patterns were analyzed by in-situ XRD as increasing temperature from room temperature to $1400^{\circ}C$ in air atmosphere. The cubic spinel phase was existed in a temperature range from $900^{\circ}C$. However, separation of NiO phase was detected from $1300^{\circ}C$, which was the origin of deterioration in the crytallinity. The surface morphology of the manufactured NTC thermistors were analyzed by FE-SEM for comparison of good and bad samples.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.14-23
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• 2018

$TiO_2-coated$ cubic ${\alpha}-Fe_2O_3$ with mostly exposed (012) and (101) facets (${\alpha}-Fe_2O_3@TiO_2$) was fabricated using a hydrothermal route for the photo-Fenton degradation of tetracycline under visible light irradiation. $TiO_2$ coating could greatly affect the photocatalytic activity of ${\alpha}-Fe_2O_3@TiO_2$. Compared with cubic ${\alpha}-Fe_2O_3$ alone for photodegradation of tetracycline, ${\alpha}-Fe_2O_3@TiO_2$ with $TiO_2$ shell of around 15 nm exhibited higher removal efficiency of tetracycline in photo-Fenton system, and its durability was slightly affected after five cycle times under same conditions. It is ascribed to the well-matched interface between cubic ${\alpha}-Fe_2O_3$ core and $TiO_2$ shell, leading to the broadened light-absorption and the efficient separation of photo-generated electon-hole pairs. The $^{\bullet}OH$ radicals were main responsible for the advanced photocatalytic performance of ${\alpha}-Fe_2O_3@TiO_2$ in visible-light driven degradation of tetracycline.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.70-75
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• 1997

An improved technique based upon an electron beam evaporation system has been developed to prepare cubic thin films In crystalline semiconductors. Zinc blonde CdSe epilayers were grown on GaAs(100) substrate by an e-beam evaporation method. The lattice parameter obtained from (400) reflection is $6.077\AA$, which is in excellent agreement with the value reported in the literature for zinc blonde CdSe. The orientation of the as-grown CdSe epilayer is determined by electron channeling patterns. The crystallinity of epitaxial CdSe layers were investigated on the double crystal X-ray rocking curve. The carrier concentration and mobility of epilayers deduced by Hall effect measurement are about $10^{18}{\textrm}{cm}^{-3}$, $10^2\textrm{cm}^2/V{\cdot}sec$ at room temperature, respectively. The photocurrent spectrum peak of the epilayer at 30 K exhibits a sharp change at 1.746 eV due to the free exciton of cubic CdSe.

• Journal of the Korean Ceramic Society
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• v.32 no.8
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• pp.915-921
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• 1995

The morphotropic phase boundary and phase transitions of the solid solutiion system, (1-x)(Na1/2Bi1/2)TiO3-PbTiO3＋xPbTiO3 were studied by investigating changes in crystal structure, variations in permittivity with temperature, and calorimetric behavior. It was observed that the morphotropic phase boundary (MPB) of this solid solutiion system was at near 14 mol% of PbTiO3. Compositions containing less than 10mol% PbTiO3 (x<0.1) exhibited a phase transition, i.e. ferroelectric rhombohedrallongrightarrowparaelectric paraelectric cubic, with increasing temperature. Composition containing more than 14 mol% PbTiO3 (x 0.14) showed a phase transition from ferroelectric tetragonal to paraelectric cubic. In the composition range of 0.1$\varepsilon$ (T) curve, which coincided with a phase transition from ferroelectric rhombohedral to an intermediate phase, was also found.

• Journal of Korea Port Economic Association
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• v.21 no.4
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• pp.55-74
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• 2005

This study focuses on affording a material basis for rearranging the manpower supply system in port and logistics industry for Busan's international competitiveness strategies. First of all, the current state and future plan of port and logistics industry, as Busan's main strategic industry, are reviewed. Then theoretical background are introduced for the estimate of demand. As a methodology of this research, Cubic model is applied to estimate the demand of manpower by using 10 year time series data from 1993 to 2002. This paper also surveyed the supply side of port and logistics industry manpower in Busan area. The amounts of mismatched equilibrium between the demand and the supply are measured in this study. The concluding remarks shows some suggestions for the problem of mismatch and the relating policy planning.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.857-860
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• 1996

The area of gear dynamics has recently been the focus of many studies. A new tooth profile modification was proposed by author for reducing vibration and noise of involute gears. A comparative dynamic analysis of the gear drive with the involute tooth and the modified tooth profile(using cubic splines) is performed to the unuformal transmission error reduces the gear vibration and noise due to less dynamic tooth load variation during the meshing cycle. This work also include a gear design process by the meaning of a practical approach, such as Win95 based simulation program with all using basic geardesign variables. Especially this program enables gear designers to dynamic analysis based on G.U.I.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.5
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• pp.463-470
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• 2005

This paper describes a method aimed at improving dead-reckoning accuracy with gyroscopes in mobile robots. The method is a precision calibration procedure for gyroscopes, which effectively reduces the ill effects of nonlinearity of the scale-factor and temperature dependency. This paper also describes the methods of gyro data collection fur all ambient temperature$(-40^{\circ}C{\~}+80^{\circ}C)$ using cubic spline interpolation and defining the error function. The sensor used was a vibrating gyroscope called the EWTS82NA21, which is low lost and commonly used in car navigation system, made by Panasonic. This angular rate sensor utilizes Coriolis force generated by a vibrating tuning fork. The paper also provides experimental results to check the performance and the effectiveness of the proposed method.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.86-89
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• 2000

In this paper, we consider a fuzzy system representation for polynomials of two variables. The representation we use is an exact transformation of the corresponding cubic spline interpolation function. We examine some of the properties of their fuzzy rule tables md prove that the rule table is symmetric or antisymmetric depending on whether the polynomial is symmetric or antisymmetric. A few examples are included to verify our proof. These results not only provide some insights on properties of the cubic spline interpolation coefficients but also provide some help in setting up fuzzy rule tables for functions of two variables.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.53
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• pp.37-44
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• 1999

The problem to be studied here is the minimization of the total travel distance and the number of vehicles used for delivering goods to customers. Vehicle routes must also satisfy a variety of constraints such as fixed vehicle capacity, allowed operating time. Genetic algorithm to solve the VRPTW with heterogeneous fleet is presented. The chromosome of the proposed GA in this study has the 3-dimension. We propose GA that has the cubic-chromosome for VRPTW with heterogeneous fleet. The newly suggested ‘Cubic-GA (or 3-D GA)’ in this paper means the 2-D GA with GLS(Genetic Local Search) algorithms and is quite flexible. To evaluate the performance of the algorithm, we apply it to the Solomon's VRPTW instances. It produces a set of good routes and the reasonable number of vehicles.