189 research outputs found
Simulation of mirror inversion of quantum states in an XY spin chain using NMR
We report an experimental quantum simulation of unitary dynamics of an XY
spin chain with pre-engineered couplings. Using this simulation, we demonstrate
the mirror inversion of quantum states, proposed by Albanese et al. [Phys. Rev.
Lett. 93, 230502 (2004)]. The experiment is performed with a 5-qubit dipolar
coupled spin system using nuclear magnetic resonance techniques. To perform
quantum simulation we make use of the recently proposed unitary operator
decomposition algorithm of Ajoy et al. [Phys. Rev. A 85, 030303 (2012)] along
with numerical pulse optimization techniques. Further, using mirror inversion,
we demonstrate that entangled states can be transferred from one end of the
chain to the other end. The simulations are implemented with high experimental
fidelity, which implies that these kind of simulations may be possible in
larger systems.Comment: 9 pages, 6 figure
Environment in Submarine Compartments
The crew operating in the confined environment of a submarine are subjected to discomfort as a result of physiological stress caused by toxic substances which are generated due to engineering, operational and other human activities. The physioiogical problems of men under prolonged confinement in a submarine have been reviewed. Data on air pollutants monitored during 'cruise' and 'at rest' conditions inside a submarine are given. Threshold limit value (TLV) of trace substances in the confined environment has been discussed. The merits of air purification and air revitalization systems currently employed for control of air pollution have been brought out
Level anti-crossings of a nitrogen-vacancy center in diamond: decoherence-free subspaces and 3D sensors of microwave magnetic fields
Nitrogen-vacancy (NV) centers in diamond have become an important tool for quantumtechnologies. All of these applications rely on long coherence times of electron and nuclear spinsassociated with these centers. Here, we study the energy level anti-crossings of an NV center indiamond coupled to a first-shell13C nuclear spin in a small static magnetic field. These levelanti-crossings (LACs) occur for specific orientations of the static magnetic field due to the strongnon-secular components of the Hamiltonian. At these orientations we observe decoherence-freesubspaces, where the electron spin coherence times (T∗2) are 5–7 times longer than those at otherorientations. Another interesting property at these LACs is that individual transition amplitudesare dominated by a single component of the magnetic dipole moment. Accordingly, this can beused for vector detection of microwave magnetic fields with a single NV center. This is particularlyimportant to precisely control the center using numerical optimal control techniques
Image Encryption Using Elliptic Curve Cryptograhy and Matrix
AbstractThe enlarged size of the internet and vast communication across it and also medical needs digital images require of security plays vital role. So different techniques are used to protect confidential image data from unauthorized access. In this paper, we propose a New encryption technique Using elliptic curve cryptography with a magic matrix operations for securing images that transmits over a public unsecured channel. There are two most important groups of image encryption algorithms: some are non chaos-based selective methods and chaos- based selective methods. The majority of these algorithms is planned for a specific image format, compressed or uncompressed
RP-HPLC Method Development and Validation for Simultaneous Estimation of Duloxetin and Methylcobalamine in Combined Dosage Form
A simple, precise, accurate, simultaneous stability indicating RP-HPLC method for the estimation of DLU (Duloxetin) and MCB (Methylcobalamine) in combined dosage form was developed using Intersil-C18 (4.6 x 250mm, 5m) in an Isocratic mode with mobile phase comprising of Phosphate buffer (pH 4.5) The flow rate was 1 mL/ min and effluent was monitored at 255.0 nm. The retention times were found to be 5.32 min for DLU and 3.59 min for MCB. The assay exhibited a linear dynamic range of 20- 120 g/mL for DLU and 10- 60 g/mL for MCB. The calibration curves were linear (r 2 = 0.999 for DLU and r 2 = 0.999 for MCB) over the entire linear range. Mean % recovery was found to be 99.68 % for DLU and 100.3 % for MCB with % RSD was NMT 2 for both estimations which fully agrees with system suitability which is in good agreement with labeled amount of formulation. The % RSD for Intra- Day and Inter-Day Precision was NMT than 2 for both the drugs. The developed method was validated as per ICH guidelines
Adaptive And Reliable GPS Uncertain Position Estimation an Insightful Oceanography and Geography Applications
Location evaluation applications are one of the most imperative services in GPS position applications. The Global Positioning Systems (GPS) is a versatile and legacy technology has been providing a reliable and accurate position of objects on Earth. The uncertain GPS position is considered an initialization parameter for many inherent systems in today’s world. This initialization position estimate has a wide variety of applications such as Coast line maps, understanding the geo-dynamical phenomena such as volcanic eruptions, earthquakes and subsequent originating source mechanisms, Mean Sea level estimation for contours of land surfaces, Oceanic en-route as well as in mobile and Vehicular technologies etc. The validation and reliability of the results of all those applications is dependent on the accuracy of the position estimate given by GPS. In this work an attempt is made to retrieve accurate and reliable position parameters from GPS by correcting the measurement errors for all the visible satellites at every epoch. The maximum and minimum pseudo ranges in L2 signal observed are 2437404.2 meters and -76295.22 meters
Power Quality Enhancement in Grid Connected PV Systems using High Step Up DC-DC Converter
Renewable energy sources (RES) are gaining more importance in the present scenario due to the depletion of fossil fuels and increasing power demand. Solar energy is the one of the most promising as it is clean and easily available source. The voltage obtained from the PV system is low. This voltage is increased by high step up dc-dc converter which uses only one switch leads to low switching losses and hence the efficiency of this converter is high. To get the good response this converter is operated in closed loop manner. Integration of PV system with existing grid has so many issues like distorted voltage, current and reactive power control etc. This paper presents a four leg inverter which works on hysteresis current control technique to address the power quality issues like reactive power compensation, balanced load currents and compensation of neutral current. The switching to the inverter is designed in such a way that it supplies the extra current to stabilise the current of the grid that is being supplied to the loads. Finally, the proposed technique is validated by using mat lab/Simulink software and corresponding results are presented in this paper
LDA BASED FACE RECOGNITION USING DCT AND HYBRID DWT
In this paper we present a hybrid approach for efficient human face recognition. The proposed method is based on linear discriminant analysis of image in DCT domain with a combination of details of DWT. And the similarity measure Minkowshi is used here. This approach reduces the storage requirement and computation time while preserving the data. The approach LDA -DCT-hybrid DWT is evaluated on Matlab using ORL face database. Compared to previous methods the proposed method improves feature extraction and retrieval rate
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