• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.1.1-4
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• 1995

In this study, PLZT thin films in AFE region prepared by sol-gel processing were investigated. And PLZT stock solutions were spin-coated on ITO-glass. The PLZT thin films were annealed by RTA. Hysteresis curves, dielectric characteristics and optical transmittances were measured in order to investigates the characteristics far the thin films. The PLZT thin films were crystallized at 750$^{\circ}C$ for 5 mimutes by RTA and the rosette structure composed of perovskite observed in the thin films. In case La content was 2/90/10 antiferroelectric-ferroelectric phase boundary was 2/90/10 PLZT thin film, and its hysteresis curve was good for application of optical information storage.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.664-666
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• 2008

Low-temperature curable organic insulator was prepared through blending of polyimide type base resin and cross-linking agent. The newly developed resin can be formed into films using a wet process and cured at $130^{\circ}C$. Using the low temperature cured film as the gate dielectric layer, the field effect mobility of $0.15\;cm^2/V{\cdot}s$ was obtained from a pentacene field effect transistor in the saturation regime and no hysteresis behavior was observed in transfer curves.

• Computational Structural Engineering
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• v.2 no.4
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• pp.79-88
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• 1989

The behavior of composite beams in steel building structures subjected to lateral loading is studied. Mathematical models for the stiffness of composite beams and the strength at the connections, which are dependent on details of the connections are developed based on the previous experimental results and the results from numerical analyses. Analytical models for the skeleton and hysteresis curves of cantilever composite beams are also presented. A single component model for the composite beam, consisting of elastic beam and the end springs at which all the inelstic deformations within a member are lumped, is implemented into the computer program, DRAIN-2D. And a comparison of analytical results is made with the experimental results.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.2B no.4
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• pp.168-173
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• 2002

A new identification algorithm for the Preisach model is presented. The algorithm treats the identification procedure of the Preisach model as an inverse problem where the independent variables are parameters of the distribution function and the objective function is constructed using only the initial magnetization curve or only tile major loop of the hysteresis curve as well as the whole reversal curves. To parameterize the distribution function, the Bezier spline and Gaussian function are used for the coercive and interaction fields axes, respectively. The presented algorithm is applied to the ferrite permanent magnets, and the distribution functions are correctly found from the major loop of the hysteresis curve or the initial magnetization curve.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.107-108
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• 2007

In order to investigate the electrical properties of Hf-silicate as a function of annealing temperature, Hf-silicate deposited by atomic layer deposition (ALD) was studied. After Hf-silicate film deposition, annealing was proceeded at $500^{\circ}C\;and\;700^{\circ}C$. The hysteresis of C-V curves and trapping charge densities were decreased after annealing process. As annealing temperature became higher from $500^{\circ}C\;to\;700^{\circ}C$, the capacitance equivalent thickness (CET) was increased from 1.66 nm to 1.76 nm and the leakage current at -1 V was decreased from $1.70{\times}10^{-4}\;to\;5.68{\times}10^{-5}\;A/cm^2$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.224-227
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• 1999

Ferroelectric Pb(Zr$\sub$0.52/Ti$\sub$0.48/)O$_3$ thin films were fabricated by pulsed laser deposition, mainly varying process conditions such as substrate temperature, oxygen pressure, and laser energy, PZT films annealed at more than 600$^{\circ}C$ were crystallized into pure perovskite phases regardless of deposition temperatures. Lower deposition temperature of 400$^{\circ}C$ accompanied with post-annealing at 650$^{\circ}C$ resulted in denser microstructures with extremely small grains compated to those of thin films annealed at higher deposition temperatures. Hysteresis curves of thin film with small grains exhibitied good squareness and low leakage characteristics.

• Steel and Composite Structures
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• v.24 no.6
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• pp.741-751
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• 2017

A steel slit shear wall has vertical slits and when it is under lateral loads, the section between these slits has double-curvature deformation, and by forming a flexural plastic hinge at the end of the slit, it dissipates the energy on the structure. In this article, Experimental, numerical and analytical analyses are performed to study the effect of slit shape and edge stiffener on the behavior of steel slit shear wall. Seismic behavior of three models with different slit shapes and two models with different edge stiffener shapes are studied and compared. Hysteresis curves, energy dissipation, out of plane buckling, initial stiffness and strength are discussed and studied. The proposed slit shape reduces the initial stiffness, increases the strength and energy dissipation. Also, edge stiffener shape increases the initial stiffness significantly.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4C
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• pp.169-175
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• 2012

Soil water retention characteristics are influenced by factors of the confining stress and hysteresis in the variably saturated soil. In the description of effective stress based on hydraulic characteristics, the contribution of a matric suction to effective stress then varies with depth or is different between the processes of infiltration and evaporation. Unsaturated effective stress can be described based on suction stress characteristic curve, in which a representative soil water retention curve is required to evaluate. Pressure palate extractor tests under various confining stresses were performed and the hysteresis of drying and wetting process was also acquired. In the process of drying or wetting, a unique relationship has been estimated on the effective volumetric water content and the matric suction, which defines suction stress characteristic curve. In the unsaturated shear strength from triaxial tests, the suction stress and the effective stress were evaluated by matric suctions. The failure envelop by effective stress based on soil water retention characteristics was unique and the same as the saturated one. The measured suction stress from triaxial tests was similar to that from the soil water retention curve. Therefore it is verified that a representative soil water retention curve can be defined which is independent of the confining effect under wetting or drying process of the hysteresis.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.363-366
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• 1988

A new $NH_{3}-O_{2}$ oxidation method was estimated by the electrical properties of the fabricated n-MOS transistor. For the C-V characteristic curves the Qox are almost equal to Qss and no hysteresis phenomena are observed. The Id-Vds characteristics show that $NH_{3}-O_{2}$ oxidation method is superior to Dry oxidation.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.3
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• pp.258-261
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• 2005

The Preisach model needs a distribution function or Everett function to simulate the hysteresis phenomena. To obtain these functions, many experimental data obtained from the first order transition curves are usually required. In this paper, a simple procedure to determine the Preisach density function using the Gaussian distribution function and genetic algorithm is proposed. The Preisach density function for the interaction field axis is known to have Gaussian distribution. To determine the density and distribution, genetic algorithm is adopted to decide the Gaussian parameters. With this method, just basic data like the initial magnetization curve or saturation curves are enough to get the agreeable density function. The results are compared with experimental data and we got good agreements comparing the simulation results with the experiment ones.