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Existing dynamic capital structure models are based on single triggers determining bankruptcy, mainly over-indebtedness or illiquidity. The latter one tends to underestimate optimal capital structures by ignoring capital providers' flexibility to inject fresh money. The former one leans towards overestimation as it neglects agency conflicts between equity investors and debt holders while implying infinitely "deep pockets" of equity investors. This article incorporates both constraints, over-indebtedness and illiquidity, examining corporate debt value and optimal capital structure in a double barrier world with knock-in and knock-out options. We are first to derive closed-form solutions for all value components of a levered firm and for the optimal capital structure in such a setting. By testing our model for firms publicly listed in the US, we gain evidence that incorporating both triggers allows for capital structure estimations that are in accordance with empirical findings.

6th International Congress and Exhibition on Advances in Applied Physics and Materials Science (APMAS) -- JUN 01-03, 2016 -- Istanbul, TURKEY, WOS: 000396118600031, Scintillation materials are widely used in digital X-ray imaging applications, radiotherapy applications coupled with suitable photoreceptors. Gd2O2SO4 (GOS) scintillator doped with trivalent praseodymium (Pr3+) presented high X-ray absorption properties and good spectral compatibility which were utilized extensively for imaging system of X-ray microscopy, soft X-ray phosphor screen for water window. In this study, GOS:0.01Pr(3+) scintillation material was synthesized by unique sol-gel process which was not previously applied and its characterization properties were investigated. Structure and luminescence properties of GOS:Pr3+ were optimized by utilizing X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and luminescence spectroscopy.

The massive parallel approach of neuromorphic circuits leads to effective methods for solving complex problems. It has turned out that resistive switching devices with a continuous resistance range are potential candidates for such applications. These devices are memristive systems - nonlinear resistors with memory. They are fabricated in nanotechnology and hence parameter spread during fabrication may aggravate reproducible analyses. This issue makes simulation models of memristive devices worthwhile. Kinetic Monte-Carlo simulations based on a distributed model of the device can be used to understand the underlying physical and chemical phenomena. However, such simulations are very time-consuming and neither convenient for investigations of whole circuits nor for real-time applications, e.g. emulation purposes. Instead, a concentrated model of the device can be used for both fast simulations and real-time applications, respectively. We introduce an enhanced electrical model of a valence change mechanism (VCM) based double barrier memristive device (DBMD) with a continuous resistance range. This device consists of an ultra-thin memristive layer sandwiched between a tunnel barrier and a Schottky-contact. The introduced model leads to very fast simulations by using usual circuit simulation tools while maintaining physically meaningful parameters. Kinetic Monte-Carlo simulations based on a distributed model and experimental data have been utilized as references to verify the concentrated model.

Various negative photoelectric effects in films of alloys of II–VI compounds deposited from a solution are studied depending on the deposition mode and heat treatment. A combined electronic-molecular mechanism of the negative photocapacitance effect, which is for the first time found in Cd1 − xZnxS and CdS1 − xSex films, and negative slowly relaxing photoelectric effects is established. The latter are caused by the transition of electrons arranged in a nanoscale surface layer from shallow energy levels of attachment centers to deeper levels with lower polarizability and by the presence of nanoscale clusters playing the role of a “reservoir” for minority carriers in these materials. A model, which makes it possible to interpret the main regularities of negative photoconductivity in Cd1 − xZnxS and CdS1 − xSex films deposited from a solution, is suggested. It is established that the negative residual photoconductivity is explained on the basis of a double barrier profile, while the negative differential photoconductivity is explained by the presence of nanoscalel electric domains.

We study the Goos-Hanchen like shifts for Dirac fermions in graphene scattered by double barrier structures. After obtaining the solution for the energy spectrum, we use the boundary conditions to explicitly determine the Goos-Hanchen like shifts and the associated transmission probability. We analyze these two quantities at resonances by studying their {main} characteristics as a function of the energy and electrostatic potential parameters. To check the validity of our computations we recover previous results obtained for a single barrier under appropriate limits., Comment: 17 pages, 7 figures, clarifications and reference added, misprints corrected. Version to appear in Physica E

This paper develops a novel analytically tractable Neumann series of Bessel functions representation for pricing (and hedging) European-style double barrier knock-out options, which can be applied to the whole class of one-dimensional time-homogeneous diffusions even for the cases where the corresponding transition density is not known. The proposed numerical method is shown to be efficient and simple to implement. To illustrate the flexibility and computational power of the algorithm, we develop an extended jump to default model that is able to capture several empirical regularities commonly observed in the literature., Comment: 19 pages, 4 tables, 3 figures

We consider discretely monitored barrier options under Levy models, including single and double barrier options and first-touch digitals, as well as CDS and defaultable bonds. At each step of backward induction, we use piece-wise polynomial interpolation and an efficient version of the Fourier transform technique, which allows for efficient error control. We derive accurate recommendations for the choice of parameters of the numerical scheme, and produce numerical examples showing that oversimplified prescriptions in other methods can result in large errors.

We establish existence results for adapted solutions of infinite horizon backward stochastic differential equations with two reflected barriers. We also apply these results to get the existence of an optimal impulse control strategy for the infinite horizon impulse control problem. The properties of the Snell envelope reduce our problem to the existence of a pair of continuous processes.

This paper introduces new and significantly fast algorithms to evaluate the price of double barrier options using binomial trees. To compute the price of double barrier options accurately, trees with large numbers of steps must be used, which is time consuming. In order to overcome this weakness, we develop new computational algorithms based on the spectral expansion method. The original idea of this method is coming from the eigenexpansion approach in PDEs. We show that this method enables us to compute double barrier options within 0.07 s, even if we use binomial trees with one billion steps. Moreover, this algorithm is easy to implement. In addition, the prices obtained by the proposed approach are always the same as those obtained by conventional binomial trees and show a good approximation to those by earlier studies.

Thin film transistors with nanoparticles silicon floating-gate are fabricated by plasma enhanced chemical vapor deposition. It should be noted that SiO2acts as both a tunneling and a blocking layer. Meanwhile, some np-Si dots are embedded within SiO2layers. The electrical characteristic of the devices are measured by semiconductor parameter analyzer at room temperature. These Thin film transistors show a good device performance with a high charge-carrier mobility of 33 cm2/vs and a large on/off ratio of 1.2×106. Moreover, the capability of written and erasing was demonstrated. This indicates that thin film transistors can be operated as rewritable nonvolatile floating gate memory devices.

In this paper, we price the valuation of double barrier Parisian options, under the Black-Scholes framework. The approach is based on fundamental partial differential equations. We reduce the dimension of partial differential equations，then using finite difference scheme to solve the partial differential equations.

The simulation is done for electron tunneling through the insulating layer of the magnetic tunnel junction with non-magnetic embedded nanoparticles (npMTJs). The distribution of the nanoparticles by size (DNPS) was important part of the solution for tunnel magnetoresistance (TMR) which was calculated on the basement of the double barrier tunneling model. It was found that theoretical agreement with experimental data can be influenced not only from DNPS but also due to different cases of the quantization. A few cases of the quantization related with a redistribution over quantum well (QW) states of the nanoparticles (NPs) (with diameter d) were considered (one of the possible DNPS and related TMR is shown in Fig. 1a and Fig. 1b).

We consider the one dimensional problem of a non-relativistic quantum particle scattering off a double barrier built from two generalized point interactions (each one characterized as a member of the four parameter family of point interactions). The properties of the double point barrier under parity transformations are investigated, using the distributional approach, and the constraints on the parameters necessary for the interaction to have a well-defined parity are obtained. We show that the limit of zero interbarrier distance of a renormalized odd arrangement with two $\delta'$ is either trivial or does not exist as a generalized point interaction. Finally, we specialize to double barriers with defined parity, calculate the phase and Salecker-Wigner-Peres clock times and argue that the emergence of the generalized Hartman effect is an artifact of the extreme opaque limit.

We study the tunneling of Dirac fermions in graphene through a double barrier potential allowing the carriers to have an effective mass inside the barrier as generated by a lattice miss-match with the boron nitride substrate. The consequences of this gap opening on the transmission are investigated. The realization of resonant tunneling conditions is also analyzed., Comment: 17 pages, 6 figures

In this paper, we study the value of the tunnel magnetoresistance (TMR) as a function of the applied voltage in double barrier magnetic tunnel junctions (DMTJs) with the left and right ferromagnetic (FM) layers being pinned and numerically estimate the possible difference of the TMR curves for negative and positive voltages in the homojunctions (equal barriers and electrodes). DMTJs are modeled as two single barrier junctions connected in series with consecutive tunneling (CST). We investigated the asymmetric voltage behavior of the TMR for the CST in the range of a general theoretical model. Significant asymmetries of the experimental curves, which arise due to different annealing regimes, are mostly explained by different heights of the tunnel barriers and asymmetries of spin polarizations in magnetic layers.

In this paper, for the first time the non-equilibrium Keldysh Green functions are used to study theoretically a device capable of generating ultra-high-frequency coherent sound. The device consists of a double barrier heterostructure (DBH) tailored to allow a resonant phonon emmission, where the electrons are injected into the system via the application of an external potential. Studies concerning the instability phenomenon of electrons and phonons fluxes were analyzed by varying the widths of the barriers. The results show that the instability disappears for a number of barrier layers less than 12 for well widths of 70 layers.

The news media often serves as an intermediary between elected officials and constituents, informing voters of the ways in which they are being represented. While the media plays a critical role in allowing representatives to communicate with constituents, previous research indicates that coverage of women and minority members of Congress may be unfavorable. Contrary to previous research, I find that being either a woman or a minority alone does not negatively impact coverage. However, faced with the “double barrier” of race and gender, minority congresswomen often receive more negative and less frequent media coverage than all other representatives.

Sport is an area in which masculinity, youth and their achievements are celebrated and rewarded. Thus, ageing women face a double barrier when they wish to participate and perform in an endeavour w...

NiSi nanocrystals of high density and good uniformity were synthesized by vapor–solid–solid growth in a gas source molecular beam epitaxy system using Si2H6 as Si precursor and Ni as catalyst. A metal–oxide–semiconductor memory device with NiSi nanocrystal–Al2O3/SiO2 double-barrier structure was fabricated. Large memory window and excellent retention at both room temperature and high temperature of 85 °C were demonstrated.

In this paper we propose a new method for pricing double-barrier options with moving barriers under the Black-Scholes and the CEV models. First of all, by applying a variational technique typical of the boundary element method, we derive an integral representation of the double-barrier option price in which two of the integrand functions are not given explicitly but must be obtained solving a system of Volterra integral equations of the first kind. Second, we develop an ad hoc numerical method to regularize and solve the system of integral equations obtained. Several numerical experiments are carried out showing that the overall algorithm is extraordinarily fast and accurate, even if the barriers are not differentiable functions. Moreover the numerical method presented in this paper performs significantly better than the finite difference approach. © 2011 Elsevier Inc. All rights reserved.

Spin-polarization asymmetry is the key parameter in asymmetric voltage behavior (AVB) of the tunnel magnetoresistance (TMR) in magnetic tunnel junctions. In this paper, we study the value of the TMR as a function of the applied voltage Va in the single as well as double barrier magnetic tunnel junctions (SMTJ & DMTJ, which are constructed from CoFeB/MgO interfaces) and numerically estimate the possible difference of the TMR-Va curves for negative and positive voltages in the homojunctions. As a result, we found that AVB may help to determine the exact values of Fermi wave vectors for minority and majority conducting spin sub-bands. Moreover, significant asymmetry of the experimental TMR-Va curves, which arises due to different annealing regimes, is explained by different heights of the tunnel barriers and values of the spin asymmetry. The numerical TMR-Va data are in good agreement with experimental ones.

Fix an integer N > 2 and let X = (X(t))t ≥ 0 be the pseudo-process driven by the high-order heat-type equation \(\partial/\partial t=\pm\partial^N\!/\partial x^N\). The denomination “pseudo-process” means that X is related to a signed measure (which is not a probability measure) with total mass equal to one. In this survey, we present several explicit results and discuss some problems concerning the pseudo-distributions of various functionals of the pseudo-process X: the first or last overshooting times of a single barrier {a} or a double barrier {a, b} by X; the sojourn times of X in the intervals [a, + ∞ ) and [a, b] up to a fixed time; the maximum or minimum of X up to a fixed time.

Double barrier metal–oxide–semiconductor tunnel diodes with ultrathin PECVD Si and thermal SiO 2 layers were fabricated. The measured capacitance–voltage and current–voltage characteristics were interpreted and physical parameters of the structures were extracted by means of a theoretical model.

The paper discusses some issues of modeling the MOS tunnel structure with a gate stack containing a semiconductor quantum well (double barrier MOS system). The considerations are illustrated by simulations with the use of a theoretical model. Results of simulations are compared with experimental characteristics of fabricated DB MOS diodes.

Combining an extended Julliere model with transfer matrix method, we study the spin-polarized resonant tunneling in GaMnAs/AlAs/GaAs/AlAs/GaMnAs double barrier ferromagnetic semiconductor (FS) tunnel junctions with the arbitrary angle θ between the magnetic directions of two FS's. It is shown that tunneling magnetoresistance (TMR) ratio linearly varies with sin 2 ( θ / 2 ) . We also demonstrate that for the heavy and light holes, the properties of the spin-polarized resonant tunneling are obviously different. The present results are expected to be instructive for manufacturing the relevant semiconductor spintronic devices.

A double-barrier superlattice infrared photodetector (SLIP) that contains a superlattice sandwiched by the thin and thick barriers has been developed. Photoelectrons can bounce back and forth between the two barriers and inject through the thin barrier to enhance the photocurrent. In comparison with the single-barrier SLIP, this structure shows at least one-order higher magnitude of photocurrent at low bias and the associated 80 K detectivity is also increased for more than one order. This detector also shows high-temperature operation above 100 K with an appropriate detectivity at low bias (1.1 × 109 cm Hz1/2/W at 0.17 V). A simple photoelectron resonance model is given to analyze the resonance phenomenon. It is found that photoelectrons excited by 9.2 µm wavelength can resonate in the bottom of the second miniband by 42 to 49 times from 0.05 to 0.15 V to enhance the photocurrent dramatically.

We evaluate the transmission and the conductance through double and triple non-uniform magnetic barriers in graphene-based nanostructures. The results indicate that non-uniform magnetic modulation results in rich transport properties. Compared with uniform double barrier magnetic structures, both the transmission and the conductance are drastically reduced through non-uniform ones. In the non-uniform triple magnetic barriers, the transmission and the conductance exhibit complicated oscillations, which vary with the width or the height of magnetic barriers. The non-uniformity introduced by altering the height and width of magnetic barriers have different effects on the transmission. For the magnetic barriers with different heights, the transmission is suppressed greatly in both low and high incident wave vector regions, while for the magnetic barriers with different widths, the obvious suppression occurs in the low incident wave vector region.

Ibuprofen (IBU) was chosen as a model drug to investigate the drug delivery rate. Mesoporous MCM-41 has been charged with ibuprofen (MCM-41_IBU). Calcium alginate was applied to encapsulate free drug and the mesoporous material. The system with double barrier demonstrated a slower release of IBU than free ibuprofen-loaded alginate beads and MCM-41_IBU. The IBU release from alginate matrix can be controlled by adjusting the free IBU/MCM-41_IBU ratio.

In this paper, we apply Carr’s randomization approximation and the operator form of the Wiener-Hopf method to double barrier options in continuous time. Each step in theresultingbackwardinductionalgorithmissolvedusingasimpleiterative procedure that reduces the problem of pricing options with two barriers to pricing a sequence of certain perpetual contingent claims with first-touch single barrier features. This procedureadmitsaclearfinancialinterpretationthatcanbeformulatedinthelanguage of embedded options. Our approach results in a fast and accurate pricing method t