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

Violation of Entropic Leggett-Garg Inequality in Nuclear Spins

We report an experimental study of recently formulated entropic Leggett-Garg inequality (ELGI) by Usha Devi et al. (arXiv: 1208.4491v2 (2012)). This inequality places a bound on the statistical measurement outcomes of dynamical observables describing a macrorealistic system. Such a bound is not necessarily obeyed by quantum systems, and therefore provides an important way to distinguish quantumness from classical behavior. Here we study ELGI using a two-qubit nuclear magnetic resonance system. To perform the noninvasive measurements required for the ELGI study, we prepare the system qubit in a maximally mixed state as well as use the `ideal negative result measurement' procedure with the help of an ancilla qubit. The experimental results show a clear violation of ELGI by over four standard deviations. These results agree with the predictions of quantum theory. The violation of ELGI is attributed to the fact that certain joint probabilities are not legitimate in the quantum scenario, in the sense they do not reproduce all the marginal probabilities. Using a three-qubit system, we experimentally demonstrate that three-time joint probabilities do not reproduce certain two-time marginal probabilities.Comment: 5 pages, 5 figures, 1 page supplementar

Managing Customer Perceived Service Quality in Private Healthcare Sector in India

Economic development and superior health care are so closely related that it is impossible to achieve one without the other. While the economic development in India is gaining momentum over the past few decades, our health system is at cross roads today. In this regard, health and health care need to be distinguished from each other for no better reason than that the former is often incorrectly seen as a direct function of the later. Indian healthcare sector is no longer limited to care rendered by or financed by government sector alone but recent time has seen massive participation of private players. At the same time superior service quality in private health care sector has been a major concern as customers have to pay a huge amount of money and effort to avail the services. The major problem in managing service quality lies in its heavy reliance on technical clinical criteria and the absence of ‘customers view’ on the services provided. Thus our main objective is to analyze perceived service quality, customer satisfaction and behavioural intention and looked at the most preferred private healthcare setting as perceived by Indian customers and the reasons thereof. At the same time we investigated and prioritized the diverse factors affecting perceived service quality and value in Indian private healthcare sector.The study uses both probability and non-probability sampling techniques for choosing the hospitals and respondents. Simple random sampling is used for availing respondents’ opinion on the subject whereas convenience and judgmental sampling is used for selection of hospitals. The sample size for respondents is determined by Hair et al., 2003 formula and found to be 384. However as increasing the sample size will reduce the sampling error we have finalized a sample size of 526 from twelve private hospitals of Odisha, Andhra Pradesh and Telangana. Analytical Hierarchy Process (AHP) was used to rank order of preferred healthcare setting with respect to the service quality dimensions and relative standings of every service provider with respect to its competitors. For decision making statistical tool such as AHP analysis, Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), Structural Equation Modeling (SEM), RIDIT analysis and GREY Relational Analysis (GRA) were used. The exploratory factor analysis was used to identify the underlying dimensions of customer perceived service quality (CPSQ) and customer perceived value (CPV) & confirmatory factor analysis (CFA) was used to confirm the factor structure and validate EFA results. Finally, the structural equation modeling (SEM) is employed to examine the hypothesized relationship

Purging of silence for robust speaker identification in colossal database

The aim of this work is to develop an effective speaker recognition system under noisy environments for large data sets. The important phases involved in typical identification systems are feature extraction, training and testing. During the feature extraction phase, the speaker-specific information is processed based on the characteristics of the voice signal. Effective methods have been proposed for the silence removal in order to achieve accurate recognition under noisy environments in this work. Pitch and Pitch-strength parameters are extracted as distinct features from the input speech spectrum. Multi-linear principle component analysis (MPCA) is is utilized to minimize the complexity of the parameter matrix. Silence removal using zero crossing rate (ZCR) and endpoint detection algorithm (EDA) methods are applied on the source utterance during the feature extraction phase. These features are useful in later classification phase, where the identification is made on the basis of support vector machine (SVM) algorithms. Forward loking schostic (FOLOS) is the efficient large-scale SVM algorithm that has been employed for the effective classification among speakers. The evaluation findings indicate that the methods suggested increase the performance for large amounts of data in noise ecosystems

Global maximum power tracking of PV system under partial shading

The increased usage of electrical energy in the recent times leads to a greater demand. It invites large development in the production of electrical energy from renewable energy sources. It involves more evolving technologies. Out of all energy extraction from solar would be abundant. Photovoltaic (PV) are one such components helps in deriving large amounts of energy, this has become more easiest method due to its economic liabilities and the world has aimed its interest in developing the PV technology, which gives clean energy. This paper objective is to implement various Maximum Power Point Tracking (MPPT) algorithms, mainly Cuckoo Search Algorithm, fuzzy logic control (FLC) and conventional perturb and observe (P&O), incremental conductance (INC) on solar PV systems. These controlled MPPT algorithms helps in driving DC-DC boost converter, which helps to obtain maximum output from the PV Panels/cells/modules/Arrays. The obtained results are compared with each other under several operating conditions. The operating conditions include change in irradiance, change in temperature dynamically, and partial shading on PV panels. The implemented MPPT algorithms require only the PV array voltage and current to control DC-DC converter, which makes them economically feasible and attractive. From the results, it can be observed that Cuckoo search algorithm gives better results under partial shading situations

Dynamic Time Slice Calculation for Round Robin Process Scheduling Using NOC

Process scheduling means allocating a certain amount of CPU time to each of the user processes.  One of the popular scheduling algorithms is the “Round Robin” algorithm, which allows each and every process to utilize the CPU for short time duration.  Processes which finish executing during the time slice are removed from the ready queue.  Processes which do not complete execution during the specified time slice are removed from the front of the queue, and placed at the rear end of the queue. This paper presents an improvisation to the traditional round robin scheduling algorithm, by proposing a new method. The new method represents the time slice as a function of the burst time of the waiting process in the ready queue. Fixing the time slice for a process is a crucial factor, because it subsequently influences many performance parameters like turnaround time, waiting time, response time and the frequency of context switches.  Though the time slot is fixed for each process, this paper explores the fine-tuning of the time slice for processes which do not complete in the stipulated time allotted to them

Monogamy of quantum correlations reveals frustration in a quantum Ising spin system: Experimental demonstration

We report a nuclear magnetic resonance experiment, which simulates the quantum transverse Ising spin system in a triangular configuration and further show that the monogamy of quantum correlations can be used to distinguish between the frustrated and non-frustrated regimes in the ground state of this system. Adiabatic state preparation methods are used to prepare the ground states of the spin system. We employ two different multipartite quantum correlation measures to analyze the experimental ground state of the system in both the frustrated and non-frustrated regimes. In particular, we use multipartite quantum correlation measures generated by monogamy considerations of negativity, a bipartite entanglement measure, and that of quantum discord, an information-theoretic quantum correlation measure. As expected from theoretical predictions, the experimental data confirm that the non-frustrated regime shows higher multipartite quantum correlations compared to the frustrated one.Comment: Title in the published version is "Multipartite quantum correlations reveal frustration in a quantum Ising spin system", 7 pages, 4 figure

Efficiency Improvement of Rotary Compressor by Improving the Discharge path through Simulation

To help raise consumer awareness on saving energy and create more energy efficient appliances, the government is upgrading the requirements of star rating of air conditioners. The enhanced star rating in air conditioners will significantly support the energy conservation and protect the environment by reducing greenhouse gas emissions in the fight against climate change. The increasing demand for star rated air-conditioners is compelling the compressor designers to develop & optimize more energy-efficient components. This paper deals with discharge port optimization in a rotary compressor, which is heart of an air-conditioner. The existing discharge port is studied & analyzed for the performance in the aspect of its capacity, EER, mass flow rate, over pressure power, area of PV diagram, motor power, valve functioning & stability. The port is redesigned to obtain improved performance, by analyzing the compressor performance parameters. Analysis is performed to study the stresses on the discharge valve and valve lift. Computational fluid dynamics is used to observe the flow behavior & pressure phenomenon in the rotary compressor, since the compressor shell accumulates the discharge gas pressure. The results are validated with the test and improved EER is observed

Green Synthesis of Silver Nanoparticles using Litsea glutinosa L. Leaves and Stem Extracts and their Antibacterial Efficacy

The present study explores the green approach for the preparation of silver nanoparticles (AgNPs) through the reduction of silver nitrate by the cell-free stem and leaf aqueous extracts of Litsea glutinosa (L.glutinosa) and its potential antibacterial activity. The analytical instruments include scanning electron microscopy, Fourier transforms infrared spectroscopy, UV-visible spectroscopy, and X-ray diffraction spectroscopy confirmed the synthesis of smaller, uniformly spherical AgNPs (10-40 nm). The average crystalline size of prepared AgNPs produced by L. glutinosa leaf extract was found to be 19 mm. From UV-visible spectral analysis, the maximum absorbance peak appeared at 444 nm for leaf extract AgNPs different from stem extract AgNPs (422 nm), which are found to be specific for AgNPs. The L.glutinosa stem extract-assisted AgNPs have shown significant antibacterial activity against Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative) in comparison to Gentamycin. Hence, the AgNPs obtained by green synthesis can be therapeutically explored against bacterial infections