• Korean Journal of Hydrosciences
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• 제4권
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• pp.33-49
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• 1993

The Purpose of this study is to classify existing hysteresis models and to discuss a possibility of a new type of the hysteresis model. The existing hysteresis models are classified into three types: the interpolation model, the scaling model and the domain model, of which only domain model is to simulate hysteresis curves based on the theoretical approach, It is useful to develop a hysteresis model that requires only one branch of hysteresis curves for the model calibration because obtaining hysteresis curves by experiments is expensive and time-concept by many investigators, however their models are not successful to accurately simulate real data of Rubicon Sandy Loam and Dune Sand. There is a possibility that a new model is based on the dependent domain concept considering the weighting factor, $P_a$($\theta$), which accounts for the pore blockage effect against air entry. Conclusively, a new model where the weighting factor $P_a$($\theta$) in Model III-1 (Mualem, 1984) reduces to a known variable through an appropriate method is an alternative model which required only one branch of main curves for the model calibration.

• 한국산림과학회지
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• 제1권1호
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• pp.1-6
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• 1962

Hysteresis Loops explaining relationship between E.M.C. and relative humidities of some commercial woods grown in Korea which have not been inspected were studied. Because of Hysteresis Loops are differently constructed among species, the loop of each species is necessary to plot in order to apply for seasoning of wood directly. Therefore relationship between E.M.C. and relative humidities, and Hysteresis Loops were inspected and compaired between species. Small sized ($3{\times}3{\times}1.3cm$) twenty pieces of wood blocks for each species were taken from log which cut few years ago and already attained air dry condition. Five relative humidity conditions (9, 32, 58, 82 and 91%) were controlled to keep constant in the cabinet under temperature $25^{\circ}C$. According to the results, it is concluded that there are considerable differences on the E.M.C. among two types of sorption, eight species and five different relative humidity conditions. Adsorption and desorption curves are showing characteristic Sigmeid Curves and desorption curves always are on the adsorption curves at all compaired species. Average hysteresis ratio is 0.75, the constructed loops of tested species are showing open hysteresis generally and flatten loop constructions of Qnerets aemitissima and Robinia pseudoaeaeia of hard wood species than other soft wood are considered to be established by differences of stability between hard and soft wood.

• 마이크로전자및패키징학회지
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• 제12권3호
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• pp.219-226
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• 2005

When a ferroelectric film has an inhomogeneous distribution of charged defects, a voltage shift in the polarization curve is induced by the internal field generated in the film. The direction and the magnitude of voltage shift in the P-V hysteresis curves obtained by the Sawyer-Tower method are different from those obtained by the virtual ground method. In this study, the asymmetric behavior in the P-V hysteresis curves of inhomogeneous ferroelectric films was investigated with a physical model and the polarization curves obtained by the Sawyer-Tower and the virtual ground methods are compared.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.255-258
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• 2003

The hysteresis characteristics of flux-lock reactor, which is an essential component of flux-lock type superconducting fault current limiter (SFCL), was investigated. The hysteresis loss of iron core in flux-lock type SFCL does not happen due to its winding's structure especially in the normal state. From the equivalent circuit for the flux-lock type SFCL and the fault current limiting experiments, the hysteresis curves could be drawn. Through the hysteresis curves together with the fault current level due to the inductance ratio for the 1st and 2nd winding, the increase of the number of turns in the 2nd winding of the flux-lock type SFCL had a role to prevent the iron core from saturation.

• 전기학회논문지
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• 제56권1호
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• pp.66-70
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• 2007

For the design to prevent the saturation of the iron core and the effective fault current limitation, the analysis for the operation of the flux-lock type superconducting fault current limiter (SFCL) with consideration for the hysteresis characteristics of the iron core is required. In this paper, the hysteresis characteristics of the flux-lock reactor, which is an essential component of the flux-lock type SFCL, were investigated. Under normal condition, the hysteresis loss of the iron core in the flux-lock type SFCL does not happen due to its winding structure. From the equivalent circuit for the flux-lock type SFCL and the fault current limiting experiments, the hysteresis curves could be drawn. From the analysis for both the hysteresis curves and the fault current limiting characteristics due to the number of turns for the 1st and 2nd windings, the increase of the number of turns in the 2nd winding of the flux-lock type SFCL had a role to prevent the iron core from saturation.

• Structural Engineering and Mechanics
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• 제16권4호
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• pp.405-422
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• 2003

Scaled brick masonry panels were tested under cyclic unialxial compression loading to evaluate its deformation characteristics. An envelope stress - strain curves, a common point curves and stability point curves were obtained for various cyclic test conditions. Loops of the stress-strain hysteresis were used to determine the energy dissipation for each cycle. Empirical expressions were proposed for the relations between energy dissipation and envelope and residual strains. These relations indicated that the decay of masonry strength starts at about two-third of peak stress.

• Steel and Composite Structures
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• 제43권2호
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• pp.139-152
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• 2022

Steel-reinforced concrete (SRC) L-shaped column is the vertical load-bearing member with high spatial adaptability. The seismic behavior of SRC L-shaped column is complex because of their irregular cross sections. In this study, the hysteretic performance of six steel truss reinforced concrete L-shaped columns specimens under the combined loading of compression, bending, shear, and torsion was tested. There were two parameters, i.e., the moment ratio of torsion to bending (γ) and the aspect ratio (column length-to-depth ratio (φ)). The failure process, torsion-displacement hysteresis curves, and bending-displacement hysteresis curves of specimens were obtained, and the failure patterns, hysteresis curves, rigidity degradation, ductility, and energy dissipation were analyzed. The experimental research indicates that the failure mode of the specimen changes from bending failure to bending-shear failure and finally bending-torsion failure with the increase of γ. The torsion-displacement hysteresis curves were pinched in the middle, formed a slip platform, and the phenomenon of "load drop" occurred after the peak load. The bending-displacement hysteresis curves were plump, which shows that the bending capacity of the specimen is better than torsion capacity. The results show that the steel truss reinforced concrete L-shaped columns have good collapse resistance, and the ultimate interstory drift ratio more than that of the Chinese Code of Seismic Design of Building (GB50011-2014), which is sufficient. The average value of displacement ductility coefficient is larger than rotation angle ductility coefficient, indicating that the specimen has a better bending deformation resistance. The specimen that has a more regular section with a small φ has better potential to bear bending moment and torsion evenly and consume more energy under a combined action.

• 센서학회지
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• 제32권4호
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• pp.238-245
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• 2023

0.75(Bi_1/2Na_1/2)TiO₃-0.25SrTiO₃ (BNT-25ST) ceramics with high densities were successfully prepared at a sintering temperature of 1,000℃ by adding a mixture of 1 mol% CuO and 0.5 mol% Na₂CO₃ or 0.5 mol% CuO and 0.25 mol% Na₂CO₃. Double polarization-electric field (P-E) hysteresis curves and sprout-shaped bipolar strain-electric field (S-E) hysteresis curves with small negative strains were observed in the pristine and CuO-added BNT-25ST ceramics whereas the Na₂CO₃-added sample showed similar P-E and S-E curves to a typical ferroelectric. The pristine BNT-25ST ceramics showed an extremely large strain and a large-signal piezoelectric strain constant (d₃₃^*): 0.287 % at 80 kV/cm and 850 pm/V at 20 kV/cm. Similar values, 0.248 % at 80 kV/cm and 655 pm/V at 20 kV/cm, were obtained in the CuO-added sample. However, the pristine and CuO-added samples showed large hysteresis in unipolar S-E curves at an electric field of less than 20 kV/cm. The Na₂CO₃-added sample showed smaller values of the strain and d₃₃^* but displayed a linear change and small hysteresis in the unipolar S-E curve. The co-added sample with CuO and Na₂CO₃ displayed intermediate P-E and S-E hysteresis curves.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.493-495
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• 2006

The hysteresis characteristics of flux-lock reactor, which is an essential component of flux-lock type superconducting fault current limiter (SFCL), was investigated. The hysteresis loss of iron core in flux-lock type SFCL does not happen due to its winding's structure especially in the normal state. From the equivalent circuit for the flux-lock type SFCL and the fault current limiting experiments, the hysteresis curves could be drawn. Through the hysteresis curves together with the fault current level due to the inductance ratio for the 1st and 2nd windings, the increase of the number of turns in the 2nd winding of the flux-lock type SFCL had a role to prevent the iron core from saturation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.43-46
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• 1995

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 showed that the model predict the hysteresis characteristic successfully. Drain current on the hysteresis characteristic currie showed an exponential variation. Hysteresis area of TFT increased with the drain voltage increase and decreases with the drain voltage decrease.