Cochin University of Science and Technology

About: Cochin University of Science and Technology is a education organization based out in Kochi, Kerala, India. It is known for research contribution in the topics: Thin film & Natural rubber. The organization has 5382 authors who have published 7690 publications receiving 103827 citations. The organization is also known as: CUSAT & Cochin University.

Microwave dielectric properties of Ba5-xSrxTa4O15, Ba5NbxTa4-xO15 and Sr5NbxTa4-xO15 ceramics

Abstract: The Ba5−xTa4SrxO15, Ba5NbxTa4−xO15 and Sr5NbxTa4−xO15 microwave dielectric ceramics were prepared by the conventional solid-state ceramic route. The dielectric properties of the ceramics were measured in the microwave frequency region. The ceramics have high dielectric constant, high quality factor (Qxf up to 37 350 GHz) and temperature coefficient of resonant frequencies in the range −60 to +78 ppm/°C depending on the value of x. The solid solutions show intermediate microwave dielectric properties in between that of the end members except for Sr5NbxTa4−xO15 which showed a lower value of the dielectric constant.

Adjusting neutrino interaction models and evaluating uncertainties using NOvA near detector data

Abstract: The two-detector design of the NOvA neutrino oscillation experiment, in which two functionally identical detectors are exposed to an intense neutrino beam, aids in canceling leading order effects of cross-section uncertainties. However, limited knowledge of neutrino interaction cross sections still gives rise to some of the largest systematic uncertainties in current oscillation measurements. We show contemporary models of neutrino interactions to be discrepant with data from NOvA, consistent with discrepancies seen in other experiments. Adjustments to neutrino interaction models in GENIE are presented, creating an effective model that improves agreement with our data. We also describe systematic uncertainties on these models, including uncertainties on multi-nucleon interactions from a newly developed procedure using NOvA near detector data.

An (s,S) inventory system with rest periods to the server

Abstract: We study the (s,S) inventory system in which the server takes a rest when the level of the inventory is zero. The demands are assumed to occur for one unit at a time. The interoccurrence times between successive demands, the lead times, and the rest times are assumed to follow general distributions which are mutually independent. Using renewal and convolution techniques we obtain the state transition probabilities.

Multimode laser emission from dye doped polymer optical fiber

Abstract: Multimode laser emission is observed in a polymer optical fiber doped with a mixture of Rhodamine 6G (Rh 6G) and Rhodamine B (Rh B) dyes. Tuning of laser emission is achieved by using the mixture of dyes due to the energy transfer occurring from donor molecule (Rh 6G) to acceptor molecule (Rh B). The dye doped poly(methyl methacrylate)-based polymer optical fiber is pumped axially at one end of the fiber using a 532 nm pulsed laser beam from a Nd:YAG laser and the fluorescence emission is collected from the other end. At low pump energy levels, fluorescence emission is observed. When the energy is increased beyond a threshold value, laser emission occurs with a multimode structure. The optical feedback for the gain medium is provided by the cylindrical surface of the optical fiber, which acts as a cavity. This fact is confirmed by the mode spacing dependence on the diameter of the fiber.