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Accurate seismic risk assessment of structures necessitates precise fragility analysis. This study focuses on the seismic fragility assessment of equipment in nuclear power plant structures, particularly emphasizing the influence of nonlinear hysteretic behavior exhibited by squat walls. By developing and comparing linear and nonlinear models of reactor containment and auxiliary buildings within a nuclear power plant, this research elucidates the significant impact of nonlinear behaviors on the seismic response and subsequent fragility curves of associated equipment and systems. Utilizing a lumped-mass stick model, the study efficiently captures the characteristics of squat shear walls, facilitating the calculation of floor response spectra and fragility for nuclear facility structures. The impacts of pinching and degradation, inherent characteristics of a squat wall’s hysteresis under cyclic loading, were identified as significant. These include the shift and change in amplitude of the floor response’s peak, along with amplification in high-frequency domains. Fragility assessments, informed by seismic response analysis, indicate significant variations in fragility curve parameters based on equipment location and frequency. The findings question the effectiveness of traditional response factor methods and general regression techniques in accurately addressing the complex probabilistic seismic demands of equipment, thus highlighting the importance of using direct analysis for calculating fragility in situations with significant nonlinearity.

In this paper, we study the effect of randomization probability p on the fundamental diagrams of the Nagel–Schreckenberg model (NS) with "slow-to-start" rule introduced by Benjamin, Johnson and Hui (BJH). It is shown that this model exhibits metastable states (which leads to the occurrence of hysteresis) only for very low values of the randomization probability (p≤0.08). Here we propose a simple generalization of the BJH model by introducing a distance-dependent randomization. With such simple generalization, the hysteresis effect and phase separation exist for all values of randomization probability. The new fundamental diagrams are analyzed within the framework of the distributions of time and distance headways.

This paper re-examines the hypothesis of unemployment hysteresis using panel data for 11 Asian countries for the period from 1980 to 2008. This study employs a variety of panel data unit root tests recently advanced by Bai and Ng (2004), Pesaran (2007) and Chang and Song (2009). The advantage of these tests is that they are able to exploit the cross-section variations of the series. In addition to these tests, a new powerful panel stationarity test proposed by Carrión-i-Silvestre et al. (2005) is applied which exploits the cross-section variations of the series and also allows for different numbers of endogenous breakpoints in the series. Our findings stress the importance of accounting exogenous shocks in the series and provide stronger evidence against the hypothesis of unemployment hysteresis for the countries analyzed. We also discover critical economic affairs which may cause the unemployment rates to fluctuate significantly. Policy implications are proposed through our observations.

In this paper, we consider the Coulomb crystals in linear ion trap with a nonlinear dissipative force induced by optical radiation. We discuss a relation between 2D and 3D ion crystals formation and the crystalline units’ initial conditions. A phase diagram of the Coulomb crystal configurations is constructed. We introduce a cross size and surface area metrics to define a Coulomb crystals dimension sensitivity to the initial conditions and show the hysteresis-like-type phase transition between 2D and 3D configurations.

We present in this paper the experimental results of transport hysteresis in an extremely imbalanced electron double-quantum-well (DQW) structure. The ratio of the top layer density (n_top) to bottom layer density (n_bot) is continuously tuned by applying voltage to a front gate. Under a condition when the top layer is nearly depleted (n_top~3×10¹⁰cm^-2) while the bottom layer remains at n_bot=1.9×10¹¹cm^-2, the hysteresis is absent in the B sweeps as long as the total Landau level filling ν<1 and the 2D electron systems are in the fractional quantum Hall effect regime. Surprisingly, a large hysteresis is observed during the gate sweeps at the same values of B and n_top. We attribute this unexpected hysteresis to the formation of an insulating state, probably a weakly pinned Wigner solid state, in the top layer.

Hysteresis V-I curves were simulated based on flux creep model. The clockwise loop was found for a sample with homogenous flux pinning if a fast current sweeping rate is used. Moreover, it is shown that an applied magnetic field can suppress the loop. The results coincide qualitatively with the relevant measurements.

The structural and dielectric properties of a PZN-PLZT solid solution were investigated. The formation of a single phase was studied by the addition of PLZT (8/60/40) in the present system. With the increase of PLZT, the content of the pyrochlore phase decreased significantly and PZN ceramics with 100% perovskite phase could be achieved with x>0.6. Dielectric properties were investigated as a function of temperature and frequency. The ferroelectric hysteresis loop shows typical characteristics of ferroelectrics.

Ferroelectric, hysteresis, impedance spectroscopy parameters, AC conductivity, and piezoelectric properties in the ceramics of Pb_0.74K_0.52Nb₂O₆ and Pb_0.74K_0.13Sm_0.13Nb₂O₆ have been studied. X-ray diffraction study reveals single phase with the orthorhombic structure. The samples were characterized for ferroelectric and impedance spectroscopy properties from room temperature to 600°C. Cole–Cole plots (Z″ versus Z′) are drawn at different temperatures. The results obtained are analyzed to understand the conductivity mechanism in both the samples. The piezoelectric constant d₃₃ has been found to be 96 × 10^-12 C/N in PKN.

A method for the estimation of reversible and irreversible susceptibilities of initial magnetization curves has been developed. It deals with the energy necessary for magnetizing and demagnetizing the sample, but neither with the nature of the magnetization processes nor with a specific type of anisotropy, so it could be applied for a wide variety of real materials. A set of minor hysteresis loops of an initially demagnetized sample, plotted with progressively increasing maximum magnetic field, has been used. The obtained results showed excellent agreement with those calculated by the remanence curve method for a Stoner–Wohlfarth model system.

We report studies of adsorption of helium in translationally invariant polygonal pores at zero temperature, with emphasis on the route to capillary condensation and the appearance of metastable states. We analyze hysteresis and hysterectic-like phenomena associated to the existence of multiple equilibrium states in a rhombic pore and examine the effects of the angular geometry, as opposed to the smooth curvature of cylindrical tubes.

The interaction of two magnetic particles separated by an interlayer is illustrated through the "astroid" curves that represent regions in the magnetic field plane where different numbers of minima associated with stable or metastable states may exist. For a single particle, we describe the astroid curves of the Stoner-Wohlfarth model. The case of two particles is then examined and found to be much more complicated. The energy landscape of the two-particle system contains ferromagnetic, antiferromagnetic and canting states that emerge in response to the level of applied magnetic field. Because of this, up to four energy minima can exist in the system, depending upon the strength of the magnetic field and the material properties of the particles.

We present an improved numerical implementation of the iterated perturbation theory, for use as an impurity solver for lattice models within dynamical mean field theory (DMFT). We demonstrate higher resolution of spectral and transport features and a reduced computational expense. Using this implementation, we study the issues of scaling and universality in spectral and transport properties of the particle-hole symmetric Hubbard model within DMFT. We re-examine experimental results for pressure-dependent resistivity in Selenium doped NiS₂ and thermal hysteresis on V₂O₃ and find qualitative agreement. A systematic study of spectral weight transfer in optical conductivity is carried out.

The ferrimagnetic mixed spin-1/2 and spin-1 cubic Ising nanowire is studied in the framework of the Monte Carlo simulation. The competition between the bilinear interaction and crystal field of spin-1 atoms as well as the nanowire size effect is highlighted. The corresponding phase diagram is discussed showing compensation points and critical second-order phase transitions. The effect of an external magnetic field and the hysteresis loops behavior are also carried out. Finally, we compare our results with other works in the literature.

We employ probabilistic method to obtain exact solutions of the zero temperature hysteresis loops of a 3-state clock model with quenched random fields in the presence of an absorbing state and in the limit of zero frequency of the applied external field. We consider discrete random fields drawn from a uniform distribution and present exact solutions of the model in one dimension. The analytical results are in excellent agreement with the simulation data of the model.

We report critical current density (J_c) behaviors of the Bi_1.7Pb_0.3-xGd_xSr₂Ca₃Cu₄O_12+y (x=0.01, 0.1) superconductors prepared by melt-quenching method and annealed in different time intervals at 840°C. The effects of annealing times are found to be very important. For example, for the sample B2, the highest value of J_c is 3.7×10⁴A/cm² at 9 K. This value is almost 1.5 and 2 times greater than that of the samples B3 and B1, respectively. With increasing annealing time, the 2223 phase increases, thus resulting in a decrease in the insulating phase. For lower annealing times, there are a large number of insulating phases. On the whole, our results indicate that there is an optimum annealing time t to form the 2223 phase, in a time interval of 120<t<192 h. It is clearly seen that J_c decreases smoothly with increasing temperature for all the samples studied. At lower temperatures, especially below 30 K, an extremely rapid decrease of J_c with increasing temperature has been observed. The experimental values also show that between the temperature interval from 9–45 K, J_c decreases by one order of magnitude. We have also observed that when the Gd–Pb substitution increases, the effective defect density increases, leading to small critical current densities.

The effect of niobium doping on the structure and electrical properties with the following compositions Pb(Zr_0.52Ti_0.48)_1-5X/4Nb_XO₃ with 0<x<0.025 was investigated. The materials were prepared by the usual ceramic technique using high purity raw materials. Disc-shaped samples of each compositions were sintered at 1250°C for 3 hours. The sample structure was determined by X-ray diffractometry. The average grain size, the maximum dielectric permittivity and the remnant polarization first increases up to x = 0.005 concentration of Nb⁵⁺ and then decreases with higher concentration of niobium, while the coercive field does not show any variation. The transition temperature decreases with the increase in niobium concentration.

The hysteresis behavior of charges was observed in Capacitance-Voltage (C-V) curve characteristics of fluorinated polyimide film in MPS (Cu-fluorinated polyimide film-Si) test structure. The degree of hysteresis was almost constant up to 150°C and then sharply increased beyond 150°C. Hysteresis behavior up to 150°C was due to a fixed amount of mobile charges at the interface between fluorinated polyimide film and Si and one beyond 150°C was due to abrupt increase of mobile charges and their enhanced movement in the bulk of fluorinated polyimide film due to structural transition of fluorinated polyimide film.

Thermal hysteresis in resistivity and magnetization of Pr_0.65Ca_0.35-xSr_xMnO₃(x = 0–0.35) manganites has been systematically studied to establish the interplay of their charge and spin-ordering. The increasing Sr concentration (x) transforms the charge-ordered (CO)/antiferromagnetic (AFM) insulating system (for x = 0) into a mixed-phased one (for x = 0.1) with sharp metal–insulator (MI) transition and finally leads to a ferromagnetic (FM) metallic (for x = 0.35) system. It has been found that the interplay of charge and spin-ordering is higher in mixed-phased state and the thermal hysteresis loop area is bigger. It increases with the increase of sharpness of MI transition. Interplay of charge and spin-ordering decreases with the increase of either CO/AFM insulating or FM metallic phase and is almost absent in completely CO/AFM insulating (with x = 0) or FM metallic (with x = 0.35) states bringing about zero thermal hysteresis loop.

Synthesis, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and magnetic measurements at low temperature of Ni metallic clusters covered by NiO, Ce₂O₃ and CeO₂, obtained from CeNi₅ powder oxidized in air at different temperatures up to 800°C, are reported. The average crystallite size of Ni core and the thickness of NiO oxide formed at the surface increase with temperature due to recrystallization processes, from 34 nm at 300°C to 77 nm at 800°C and from 9 nm to 19 nm, respectively. Ni metallic component was detected both in XPS valence bands and core levels spectra only after sputtering. The hysteresis loop presents a small shift towards negative magnetic fields which confirms the presence of ferromagnetic Ni/antiferromagnetic NiO interfaces.

Ferromagnetic shape memory alloy (FSMA) is one of the smart materials which finds increasing industrial applications. This paper deals with the effect of Mn substitution for Ga on martensitic and magnetic transformation temperature of polycrystalline Ni–Mn–Ga alloy prepared in argon atmosphere. The prepared alloy has been characterized by means of scanning electron microscopy (SEM), differential scanning calorimeter (DSC), and superconducting quantum interference device (SQUID). Magnetic property of alloy has been analyzed with vibrating sample magnetometer (VSM). From the VSM measurement, it is studied that the saturation magnetization of polycrystalline ferromagnetic shape memory occurs at high magnetic field. The main finding of this article is the raise in transformation temperature by 28 K/atom. As the working temperature is above room temperature, it seems to be a promising candidate for practical applications. The result reported here may help for further research in the field of polycrystalline Ni–Mn–Ga alloy.