Sleep apnea syndrome (SAS) is a common sleep disorder, which has been shown to be an important contributor major neurocognitive and cardiovascular sequelae. Considering current diagnostic strategies are limited with bulky medical devices high examination expenses, large number of cases go undiagnosed. To enable large-scale screening for SAS, wearable photoplethysmography (PPG) technologies have used as early detection tool. However, existing algorithms energy-intensive require amounts memory...

We propose an optical cryptosystem for encrypting images of multi-depth objects based on the combination heterodyne technique and fingerprint keys. Optical heterodyning requires two beams to be mixed. For encryption, each beam is modulated by mask containing either person who sending, or receiving image. The pair masks are taken as encryption Subsequently, used scan over a 3-D object obtain encrypted hologram. During decryption process, sectional image recovered convolving its hologram...

Fingerprint authentication is a preferable biometric technique for securing images. Optical scanning cryptography (OSC) hybrid optical/digital method to encrypt and decrypt an image using optical technique. In this paper, we propose new strategy combine OSC with fingerprints enhance security. We have verified the effectiveness of proposed idea in simulations. Subsequently practical implementation has also been performed heterodyning confirm results from discussed added security flexibility...

We treat the Kapitza-Dirac diffraction effect observed recently by Batelaan et al. using a newly developed nonperturbative quantum-field scattering theory. Our theory shows that an electron beam passing perpendicularly through focused standing light wave can produce patterns. predicts (1) minimum value of ponderomotive energy is (Planck's over 2 pi omega)(2)/m(e)c(2), (2) critical laser intensity above which first pair peaks will occur, and (3) existence sidebands in spectra separated far...

Geologic subsurface energy storage, such as porous-media compressed-air storage (PM-CAES) and underground hydrogen (UHS), involves the multi-phase fluid transport in structurally disordered or heterogeneous porous media (e.g., soils rocks). Furthermore, is likely to repeatedly occur due successive injections extractions, thus, resulting cyclic drainage–imbibition processes. To complement our preceding study, we conducted a follow-up study with microfluidic pore-network devices square solid...

In this paper, we describe a generalized version of multicarrier CDMA (MC-CDMA) that extends to multiple frequency sub-bands or bands. We term frequency-generalized MC-CDMA (FG-MC-CDMA). This technique can provide more flexibility in selection data rates and larger diversity order than comparable schemes, by generalizing allow for different spreading factors. the scheme's principles operation, analytical simulation results its use multi-band channels. Our show FG-MC-CDMA be an attractive...

A scaling law which was used to classify photoelectron angular distributions (PADs) is now extended kinetic energy spectra. Both a theoretical proof and an independent verification are presented. Considering PADs of momentum spectra, this extension really extends the entire energy-momentum The for spectra applies both directly ionized rescattered photoelectrons. Re-scaling experimental input parameters without loosing physical essence with may ease conditions reduce material consumptions in...

We observed efficient terahertz (THz) emission from sol-gel grown Cu2ZnSnSe4 (CZTSe) thin films using THz time domain spectroscopy technique. The bandwidth exceeds 2 with a dynamic range of 20 dB in the amplitude spectrum. CZTSe is found to be independent external magnetic fields. Comparing polarity waveforms and GaAs, we suggest that acceleration photo-carriers surface accumulation layer dominant mechanism radiation emission. Optical excitation fluence dependence measurements show...

Using a nonperturbative quantum electrodynamics theory of high-order harmonic generation (HHG), scaling law HHG is established. The states that when the atomic binding energy Eb, wavelength λ and intensity I laser field change simultaneously to kEb, λ/k, k3I, respectively. characteristics spectrum remain unchanged, while yield enhanced k3 times. That obeys same with above-threshold ionization solid proof fact two physical processes have similar mechanisms. variation integrated yields also discussed.

To meet increasing communication demands on airport surface areas, several systems have been proposed. The OFDMA based IEEE 802.16e system and other multicarrier such as code division multiple access (MC- CDMA) are of great interest, since they provide flexible data rates good performance. In this paper, the performance multi-carrier transmission schemes, including OFDMA, spread spectrum (SS-MC- MA), frequency generalized CDMA (FG-MC-CDMA), evaluated area channels. All considered here can be...

In order to solve the long-time prediction problem of soil moisture under different depth conditions, this paper proposes a model based on ARIMA time-series model. Soil data at three depths 10cm, 40cm and 100cm are smoothed noise-reduced, then processed input into constructed LSTM for prediction, results show that combined has better compared with LSTM, finally, Pearson correlation coefficient filter out precipitation (mm), average The four independent variables, mean wind speed (knots),...

By developing a full quantum scattering theory of high-order above-threshold ionization, we study the energy spectra and angular distributions photoelectrons from atoms with intense laser fields shining on them. We find that real rescattering can occur many times, even infinite times. The process form broad plateau in kinetic-energy spectrum. further disclose multiple-plateau structure formed by high-energy photoelectrons, which absorb photons during process. Moreover, both obey same scaling...

The photoelectron angular distributions (PADs) from above-threshold ionization of atoms irradiated by one-cycle laser pulses satisfy a scaling law. law denotes that the main features PADs are determined four dimensionless parameters: (1) ponderomotive number up = Up/ℏω, energy Up in units photon energy; (2) binding εb Eb/ℏω, atomic Eb (3) absorbed photons q; (4) carrier-envelope phase ϕ0, carrier wave with respect to envelope. We verify theoretical analysis and numerical calculation,...

We theoretically investigate the feasibility of terahertz generation and detection in a 〈110〉-oriented 3C-SiC single crystal excited by frequency-doubled Yb-doped femtosecond pulse laser. The phase-matching condition optical rectification (OR) electro-optic (EO) sampling are analyzed on basis dispersion relation 3C-SiC. THz bandwidth as well peak frequency position via OR calculated at different thicknesses. EO is discussed 2 schemes. In collinear incidence scheme, cut-off function thickness...

Abstract A Wigner-distribution-like (WDL) function based on the strong-field approximation (SFA) theory is used to investigate ionization time of photoelectron emitted from initial states with different magnetic quantum number m in elliptically polarized electric fields. The saddle-point method adopted for comparisons. For states, a discrepancy exists WDL distributions photoelectrons direction close major axis laser field ellipse. Based analysis, this can be ascribed interference between...