• 대한전기학회논문지
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• 제43권7호
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• pp.1135-1143
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• 1994

We fabricate a bottom gate a-Si:H TFT on N-Type <100> Si wafer. According to the Variation of gate and drain voltage, the hysteresis characteristic curves were measured experimentally. Also, we proposed model equation and showed that the model predict the hysteresis characteristic successfully. Drain current on the hysteresis characteristic curve showed an exponential variation. Hysteresis area of TFT increased with the drain voltage increase and decreases with the drain voltage decrease.

• Geomechanics and Engineering
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• 제28권2호
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• pp.107-116
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• 2022

The steady state of unsaturated soil takes a long time to achieve. The soil seepage behaviours and hydraulic properties depend highly on the wetting/drying rate. It is observed that the soil-water characteristic curve (SWCC) is dependent on the wetting/drying rate, which is known as the dynamic effect. The dynamic effect apparently influences the scanning curves and will substantially affect the seepage behavior. However, the previous models commonly ignore the dynamic effect and cannot quantitatively describe the hysteresis scanning loops under dynamic conditions. In this study, a dynamic hysteresis model for SWCC is proposed considering the dynamic change of contact angle and the moving of the contact line. The drying contact angle under dynamic condition is smaller than that under static condition, while the wetting contact angle under dynamic condition is larger than that under static condition. The dynamic contact angle is expressed as a function of the saturation rate according to the Laplace equation. The model is given by a differential equation, in which the slope of the scanning curve is related to the slope of the boundary curve by means of contact angle. Empirical models can simulate the boundary curves. Given the two boundary curves, the scanning curve can be well predicted. In this model, only two parameters are introduced to describe the dynamic effect. They can be easily obtained from the experiment, which facilitates the calibration of the model. The proposed model is verified by the experimental data recorded in the literature and is proved to be more convenient and effective.

• 한국전기전자재료학회논문지
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• 제28권10호
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• pp.658-664
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• 2015

This paper presents an electrical feature analysis of hysteresis curves in memristor differential and intergral control circuit. After making macro model of the memristor device, electric characteristics of the model such as time analysis, frequency dependent DC I-V curves were performed by PSPICE simulation. Also, we made a circuit of memristor-capacitor based on nano-wired memristor device and analyzed the simulated PSPICE results. Finally, we proposed a memristor based differential or integral control circuit, analyzed hysteresis curve characteristic in the control circuit.

• 한국소음진동공학회논문집
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• 제12권8호
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• pp.648-656
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• 2002

This paper presents the identification of temperature-dependent hysteresis of an electro-rheological (ER) fluid under various operating temperatures using the Preisach model. As a first step, polymethylaniline (PMA) particles are prepared and mixed with silicone oil to make an ER fluid. A couette type electroviscometer is then employed to obtain the field-dependent shear stress. In order to show the suitability of the Preisach model to predict a physical hysteresis phenomenon of the ER fluid, two significant properties; the minor loop property and the wiping-out property are experimentally examined under three dominant temperature conditions. Subsequently, the Preisach model for the PMA-based ER fluid is identified using experimental multiple first order descending (FOD) curves. The effectiveness of the identified hysteresis model is verified in the time domain by comparing the predicted field-dependent shear stress with the measured one under the both specified and unspecified temperatures. In addition, the hysteresis model proposed in this work is compared to Bingham model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.3-5
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• 1996

The Preisach model needs density function or Everett function for the sample material to calculate the hysteresis characteristics. To obtain these functions, many experimental data obtained from the first order transition curves are required. However, it is not simple task to measure the curves. In this paper, a simple generalized technique to get the Everett function using saturation hysteresis loop and two first order transition curves is proposed. These three data makes three equations for the proposed Everett function model and we can get three variables by those equations. From the simulation, we got acceptable results.

• Structural Engineering and Mechanics
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• 제77권2호
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• pp.261-272
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• 2021

The energy-saving block and invisible multi-ribbed frame composite wall (EBIMFCW) is a new type of load-bearing wall. The study of this paper focus on it is hysteresis rule under horizontal cyclic loading. Firstly, based on the experimental data of the twelve specimens under horizontal cyclic loading, the influence of two important parameters of axial compression ratio and shear-span ratio on the restoring force model was analyzed. Secondly, a tetra-linear restoring force model considering four feature points and the degradation law of unloading stiffness was established by combining theoretical analysis and regression analysis of experimental data, and the theoretical formula of the peak load of the EBIMFCW was derived. Finally, the hysteretic path of the restoring force model was determined by analyzing the hysteresis characteristics of the typical hysteresis loop. The results show that the curves calculated by the tetra-linear restoring force model in this paper agree well with the experimental curves, especially the calculated values of the peak load of the wall are very close to the experimental values, which can provide a reference for the elastic-plastic analysis of the EBIMFCW.

• Journal of Mechanical Science and Technology
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• 제20권5호
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• pp.634-642
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• 2006

The aim of this paper is to increase the performance of hysteresis compensation for Shape Memory Alloy (SMA) actuators by using inverse Preisach model in closed-loop control system. This is used to reduce hysteresis effects and improve accuracy for the displacement of SMA actuators. Firstly, hysteresis is identified by numerical Preisach model implementation. The geometrical interpretation from first order transition curves is used for hysteresis modeling. Secondly, the inverse Preisach model is formulated and incorporated in closed-loop PID control system in order to obtain desired current-to-displacement relationship with hysteresis reducing. The experimental results for hysteresis compensation by using this method are also shown in this paper.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2048-2053
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• 2005

The aim of this paper is to compensate hysteresis phenomena in Shape Memory Alloy (SMA) actuators by using numerical inverse Preisach model. This is used to design a controller that correct hysteresis effects and improve accuracy for the displacement of SMA actuators. Firstly, hysteresis is identified by numerical Preisach model implementation. The geometrical interpretation from first order transition curves is used for hysteresis modeling. Secondly, the inverse Preisach model is formulated and incorporated in open-loop control system in order to obtain desired input-output relationship with hysteresis reducing. The experimental results for hysteresis compensation by using this method are also shown in this paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.83-85
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• 2007

In magnetic field analysis of electrical machines, hysteresis phenomena of B-H curves should be taken into account in order to obtain more accurate results. In this paper, the hysteresis modeling using the micromagnetics for the magnetic field analysis is investigated. In the micromagnetics, usually, it takes much CPU times. Therefore, the method for representing hysteresis phenomena by minimum modeling is investigated in order to applying it to the magnetic field analysis. First, the micromagnetics is described. Then, the method of minimum modeling is shown. Finally, the hysteresis curve obtained by the minimum modeling is demonstrated. The effect of parameters of micromagnetics on the shape of hysteresis curve is investigated.

• The Korean Journal of Ceramics
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• 제5권4호
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• pp.414-418
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• 1999

The synthesis of polycrystalline $Al_2TiO_5$ ceramics with low thermal expansion by fusion in an electric arc furnance was investigated. The thermal expansion curves of $Al_2TiO_5$ ceramics were lowered because of microcracks caused by the strong thermal expansion anisotropy of the crystal axes and were accompanied by hysteresis curves. These phenomena are explained by the opening and closing of microcracks. The difference in microcracking temperatures of dilatometric cooling curves in the range of 400~$620^{\circ}C$ is caused by the difference in sintering temperature, grain size and stabilization status.