The ability to detect and deal with errors when manipulating quantum systems is a fundamental requirement for fault-tolerant quantum computing. Unlike classical bits that are subject to only digital ...bit-flip errors, quantum bits are susceptible to a much larger spectrum of errors, for which any complete quantum error-correcting code must account. Whilst classical bit-flip detection can be realized via a linear array of qubits, a general fault-tolerant quantum error-correcting code requires extending into a higher-dimensional lattice. Here we present a quantum error detection protocol on a two-by-two planar lattice of superconducting qubits. The protocol detects an arbitrary quantum error on an encoded two-qubit entangled state via quantum non-demolition parity measurements on another pair of error syndrome qubits. This result represents a building block towards larger lattices amenable to fault-tolerant quantum error correction architectures such as the surface code.
We estimate the distribution of ice thickness for a Himalayan glacier using surface velocities, slope and the ice flow law. Surface velocities over Gangotri Glacier were estimated using sub-pixel ...correlation of Landsat TM and ETM+ imagery. Velocities range from ˜14–85 m a–1 in the accumulation region to ˜20–30 m a–1 near the snout. Depth profiles were calculated using the equation of laminar flow. Thickness varies from ˜540 m in the upper reaches to ˜50–60 m near the snout. The volume of the glacier is estimated to be 23.2 ± 4.2 km3.
•Performance assessment of a 20kWp solar photovoltaic system installed at Indian Institute of Science, Bangalore.•In summer, maximum module efficiency is attained at 45°C, whereas in winter, it is at ...55°C.•Performance ratio of the PV system is inversely proportional to the module temperature.
A 20kWp Solar Photovoltaic (SPV) system was set up on the library roof-top in Indian Institute of Science, Bangalore, India. This roof-top photovoltaic (RTPV) system partly powers the Central Office of IISc. The main objective of setting up this SPV system was to study the performance of solar plants under different seasons and climatic conditions of Bangalore. The system has been producing an average daily yield of approximately 80kWh for the past two years which translates to an annual yield of 28.9MWh. The overall yield of the system up to 14th September 2015 is 70MWh. This work focuses on the evaluation of the performance of SPV systems using the popular grading systems, namely Capacity Utilization Factor (CUF) and Performance Ratio (PR). The CUF of the SPV system is 16.5%, which lies within the range of CUF of well-performing solar plants located in India. Average Performance Ratio (PR) of the SPV system is around 85%, which indicates that the performance of the SPV system is satisfactory. PR of the SPV system is correlated with the behaviour of SPV modules in different seasons, with module temperature (Tmod) as the key factor of comparison. In summer, the SPV modules attain maximum efficiency (ηmax) at Tmod of 45°C, but in winter, it is at 55°C. In summer, for Tmod>45°C, module efficiency (η) reduces by 0.08% per degree rise in temperature. In monsoon, for Tmod>35°C, η reduces by 0.04% per degree rise in temperature. In post-monsoon period, for Tmod>38°C, η reduces by 0.06% per degree rise temperature. However, in winters, the modules attain ηmax at Tmod of 55°C, without much drop in efficiency. This is mainly because of intermittent natural cooling that takes places at the surface of the modules, due to cool breeze and lower ambient temperatures.
Mediated photon-photon interactions are realized in a superconducting coplanar waveguide cavity coupled to a superconducting charge qubit. These nonresonant interactions blockade the transmission of ...photons through the cavity. This so-called dispersive photon blockade is characterized by measuring the total transmitted power while varying the energy spectrum of the photons incident on the cavity. A staircase with four distinct steps is observed and can be understood in an analogy with electron transport and the Coulomb blockade in quantum dots. This work differs from previous efforts in that the cavity-qubit excitations retain a photonic nature rather than a hybridization of qubit and photon and provides the needed tolerance to disorder for future condensed matter experiments.
•GHI is derived from INSAT-3D satellite’s visible channel imagery over India.•Satellite derived GHI is validated against 19 ground-based stations across India.•Gridded satellite GHI is used to ...spatially validate WRF model forecast over India.
Geostationary satellites offer the possibility of producing high-frequency time series irradiance datasets, covering a large geographical area. Here, we derive half-hourly global irradiance (GHI) at 4 km spatial resolution from visible channel radiance of INSAT-3D satellite using a semi-empirical model and validate it against 19 ground stations over 2015–16, across India. Our model uses the Advanced Solis clear-sky model with monthly climatological values of modern-era retrospective analysis for research and applications-2 (MERRA-2) aerosol optical depth (AOD) and precipitable water (PW) as inputs. The relative root mean squared error (rRMSE) and relative mean bias error (rMBE) are 24.02% and −0.05%, respectively. Over the validation period, INSAT-3D derived GHI outperformed SARAH-E model and MERRA-2 reanalysis GHI.
Both medullary thymic epithelial cells (mTEC) and dendritic cells (DC) present tissue-restricted antigens (TRA) to thymocytes to induce central tolerance, but the relative contributions of these ...antigen-presenting cell (APC) subsets remain unresolved. Here we developed a two-photon microscopy approach to observe thymocytes interacting with intact APCs presenting TRAs. We find that mTECs and DCs cooperate extensively to induce tolerance, with their relative contributions regulated by the cellular form of the TRA and the class of major histocompatibility complex (MHC) on which antigen is presented. Even when TRA expression is restricted to mTECs, DCs still present self-antigens at least as frequently as mTECs. Notably, the DC subset cDC2 efficiently acquires secreted mTEC-derived TRAs for cross-presentation on MHC-I. By directly imaging interactions between thymocytes and APCs, while monitoring intracellular signaling, this study reveals that distinct DC subsets and AIRE
mTECs contribute substantially to presentation of diverse self-antigens for establishing central tolerance.
Vertically integrated eastward moisture flux at 70° E over the Arabian Sea (Q) is the dominant factor that drives seasonal Indian summer monsoon rainfall (ISMR). Yet, the nature of this relationship ...depends on the phase of El-Nino Southern Oscillation (ENSO). The conversion efficiency of Q to rainfall is twice as high during the El-Nino years than La-Nina years. This increased sensitivity of ISMR to Q during the El-Nino years causes positive feedback to reduce Q further. As a result, droughts are more frequent and more vigorous than floods, manifesting as a negatively skewed non-Gaussian probability distribution function of ISMR. A non-linear multi regression model using Q and ENSO explained the observed skewness of ISMR with the severity of droughts. Besides, droughts have frequent long break-spells of rainfall, characterized by zonal circulation with an ascending branch over the western North Pacific Ocean and descending branch over the Indian region, which may cause moisture divergence and hence the moist stability over India. The increased stability in droughts might determine the conversion efficiency of Q to rainfall. This zonal dipole pattern of circulation anomaly over India and the western North Pacific Ocean in long break spells is manifest about 10-days before the advent of break conditions.
With favourable error thresholds and requiring only nearest-neighbour interactions on a lattice, the surface code is an error-correcting code that has garnered considerable attention. At the heart of ...this code is the ability to perform a low-weight parity measurement of local code qubits. Here we demonstrate high-fidelity parity detection of two code qubits via measurement of a third syndrome qubit. With high-fidelity gates, we generate entanglement distributed across three superconducting qubits in a lattice where each code qubit is coupled to two bus resonators. Via high-fidelity measurement of the syndrome qubit, we deterministically entangle the code qubits in either an even or odd parity Bell state, conditioned on the syndrome qubit state. Finally, to fully characterize this parity readout, we develop a measurement tomography protocol. The lattice presented naturally extends to larger networks of qubits, outlining a path towards fault-tolerant quantum computing.
The clothing design based on sweat distribution pattern is called as body mapping clothing. Comparisons of three designs of body mapped and one conventional design of T-shirt was done in a wearer ...testing at a controlled chamber of 33 °C and 60% relativity humidity in a treadmill at 12 km/h for 40 min followed by 10 min resting. It is concluded that with the full body mapped T-shirt the increase in skin temperature is reduced in the chest area, shoulder, the body back by 47%,44% and 55% respectively; the increase in skin micro climate relative humidity is reduced in the chest area, shoulder, the body back by 54%,39.2% and 53% respectively; the increase in heart beat rate is reduced by 5.1%; the subjective perceptions of skin temperature, skin moisture and comfort are better; the wearer will be able to improve the running performance due better comfort level in terms lesser increase skin temperature, skin micro climate relative humidity and heart beat rate.
•Body Mapping Clothing (BMC) helps in improving thermal physiological benefit of the wearer in running.•The subjective sensations of comfort is better in BMC.•BMC helps in improving thermal physiological benefit in post running resting.•BMC helps in improving the running speed.
We demonstrate ultrahigh speed spectral / Fourier domain optical coherence tomography (OCT) using an ultrahigh speed CMOS line scan camera at rates of 70,000 - 312,500 axial scans per second. Several ...design configurations are characterized to illustrate trade-offs between acquisition speed, resolution, imaging range, sensitivity and sensitivity roll-off performance. Ultrahigh resolution OCT with 2.5 - 3.0 micron axial image resolution is demonstrated at approximately 100,000 axial scans per second. A high resolution spectrometer design improves sensitivity roll-off and imaging range performance, trading off imaging speed to 70,000 axial scans per second. Ultrahigh speed imaging at >300,000 axial scans per second with standard image resolution is also demonstrated. Ophthalmic OCT imaging of the normal human retina is investigated. The high acquisition speeds enable dense raster scanning to acquire densely sampled volumetric three dimensional OCT (3D-OCT) data sets of the macula and optic disc with minimal motion artifacts. Imaging with approximately 8 - 9 micron axial resolution at 250,000 axial scans per second, a 512 x 512 x 400 voxel volumetric 3D-OCT data set can be acquired in only approximately 1.3 seconds. Orthogonal registration scans are used to register OCT raster scans and remove residual axial eye motion, resulting in 3D-OCT data sets which preserve retinal topography. Rapid repetitive imaging over small volumes can visualize small retinal features without motion induced distortions and enables volume registration to remove eye motion. Cone photoreceptors in some regions of the retina can be visualized without adaptive optics or active eye tracking. Rapid repetitive imaging of 3D volumes also provides dynamic volumetric information (4D-OCT) which is shown to enhance visualization of retinal capillaries and should enable functional imaging. Improvements in the speed and performance of 3D-OCT volumetric imaging promise to enable earlier diagnosis and improved monitoring of disease progression and response to therapy in ophthalmology, as well as have a wide range of research and clinical applications in other areas.
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