9,516 research outputs found
Nonfactorization in Hadronic Two-body Cabibbo-favored decays of D^0 and D^+
With the inclusion of nonfactorized amplitudes in a scheme with , we
have studied Cabibbo-favored decays of and into two-body hadronic
states involving two isospins in the final state. We have shown that it is
possible to understand the measured branching ratios and determined the sizes
and signs of nonfactorized amplitudes required.Comment: 15 pages, Late
Non-degenerate, three-wave mixing with the Josephson ring modulator
The Josephson ring modulator (JRM) is a device, based on Josephson tunnel
junctions, capable of performing non-degenerate mixing in the microwave regime
without losses. The generic scattering matrix of the device is calculated by
solving coupled quantum Langevin equations. Its form shows that the device can
achieve quantum-limited noise performance both as an amplifier and a mixer.
Fundamental limitations on simultaneous optimization of performance metrics
like gain, bandwidth and dynamic range (including the effect of pump depletion)
are discussed. We also present three possible integrations of the JRM as the
active medium in a different electromagnetic environment. The resulting
circuits, named Josephson parametric converters (JPC), are discussed in detail,
and experimental data on their dynamic range are found to be in good agreement
with theoretical predictions. We also discuss future prospects and requisite
optimization of JPC as a preamplifier for qubit readout applications.Comment: 21 pages, 16 figures, 4 table
Femtosecond Photoionization of Atoms under Noise
We investigate the effect of incoherent perturbations on atomic
photoionization due to a femtosecond mid-infrared laser pulse by solving the
time-dependent stochastic Schr\"odinger equation. For a weak laser pulse which
causes almost no ionization, an addition of a Gaussian white noise to the pulse
leads to a significantly enhanced ionization probability. Tuning the noise
level, a stochastic resonance-like curve is observed showing the existence of
an optimum noise for a given laser pulse. Besides studying the sensitivity of
the obtained enhancement curve on the pulse parameters, such as the pulse
duration and peak amplitude, we suggest that experimentally realizable
broadband chaotic light can also be used instead of the white noise to observe
similar features. The underlying enhancement mechanism is analyzed in the
frequency-domain by computing a frequency-resolved atomic gain profile, as well
as in the time-domain by controlling the relative delay between the action of
the laser pulse and noise.Comment: 10 pages, 10 figure
Optimal Stochastic Enhancement of Photoionization
The effect of noise on the nonlinear photoionization of an atom due to a
femtosecond pulse is investigated in the framework of the stochastic
Schr\"odinger equation. A modest amount of white noise results in an
enhancement of the net ionization yield by several orders of magnitude, giving
rise to a form of quantum stochastic resonance. We demonstrate that this effect
is preserved if the white noise is replaced by broadband chaotic light.Comment: 4 pages, 4 figure
Perbandingan Model Estimasi Kandungan Nitrogen Padi Menggunakan Citra Hiperspektral dan Multispektral Sebagian Wilayah Kabupaten Sleman
Penelitian ini memiliki tujuan untuk mengetahui kemampun citra hipersepektral dan multispektral dalam mengestimasi kandungan nitrogen padi di sebagian wilayah Kabupaten Sleman menggunakan pendekatan semi-empiris. Bersamaan dengan itu juga menghitung besarnya akurasi pemetaan yang didapatkan. Diukur pula kemampuan data penginderaan multisensor untuk memetakan penggunaan lahan, sawah irigasi, yang menjadi dasar pengambilan data. Citra Hyperion dan citra Landsat 8 OLI digunakan sebagai data rujukan untuk pembuatan model estimasi.Hasil penelitian menunjukkan bahwa citra Hyperion dapat menyajikan informasi penggunaan lahan lebih baik dibandingkan dengan citra Landsat 8 OLI dengan akurasi pemetaan sebesar 87,78%. Model estimasi nitrogen padi terbaik dimiliki oleh NDNI (Hyperion) dengan nilai RMSE 0,45 dan r 0,53. Diikuti oleh OSAVI (Hyperion) RMSE=0,50, OSAVI (Landsat 8 OLI) RMSE=0,67 dan NDNI (Landsat 8 OLI) RMSE=0,80. Berdasarkan informasi tersebut, citra hiperspektral mampu menggambarkan informasi nitrogen padi di wilayah kajian lebih baik dibandingkan dengan citra Landsat 8 OLI. Hal ini disebabkan oleh karakteristik spektral citra
Heisenberg-limited qubit readout with two-mode squeezed light
We show how to use two-mode squeezed light to exponentially enhance
cavity-based dispersive qubit measurement. Our scheme enables true
Heisenberg-limited scaling of the measurement, and crucially, is not restricted
to small dispersive couplings or unrealistically long measurement times. It
involves coupling a qubit dispersively to two cavities, and making use of a
symmetry in the dynamics of joint cavity quadratures (a so-called
quantum-mechanics-free subsystem). We discuss the basic scaling of the scheme
and its robustness against imperfections, as well as a realistic implementation
in circuit quantum electrodynamics.Comment: 5 pages, 4 figures, Supplemental Materia
On some generalized ageing orderings
Some partial orderings which compare probability distributions with the expo-
nential distribution, are found to be very useful to understand the phenomenon
of ageing. Here, we introduce some new generalized partial orderings which de-
scribe the same kind of characterization of some generalized ageing classes. We
give some equivalent conditions for each of the orderings. Inter-relations
among the generalized orderings have also been discussed
Inelastic Final-State Interactions and Two-body Hadronic B decays into Single-Isospin channels
The role of inelastic final-state interactions in CP asymmetries and
branching ratios is investigated in certain chosen single isospin two-body
hadronic B decays. Treating final-state interactions through Pomeron and Regge
exchanges, we demonstrate that inelastic final state interactions could lead to
sizeable effects on the CP asymmetry.Comment: 23 pages, Latex, 1 eps-figur
Human Depth Sensors-based Activity Recognition using Spatiotemporal Features and Hidden Markov Model for Smart Environments
116Yscopu
Depth Images-based Human Detection, Tracking and Activity Recognition Using Spatiotemporal Features and Modified HMM
Human activity recognition using depth information is an emerging and challenging technology in computer vision due to its considerable attention by many practical applications such as smart home/office system, personal health care and 3D video games. This paper presents a novel framework of 3D human body detection, tracking and recognition from depth video sequences using spatiotemporal features and modified HMM. To detect human silhouette, raw depth data is examined to extract human silhouette by considering spatial continuity and constraints of human motion information. While, frame differentiation is used to track human movements. Features extraction mechanism consists of spatial depth shape features and temporal joints features are used to improve classification performance. Both of'these features are fused together to recognize different activities using the modified hidden Markov model (M-HMM). The proposed approach is evaluated on two challenging depth video datasets. Moreover, our system has significant abilities to handle subject's body parts rotation and body parts missing which provide major contributions in human activity recognition.1165Ysciescopuskc
- …
