Geometry of mixed states and degeneracy structure of geometric phases for multi-level quantum systems. A unitary group approach

We analyze the geometric aspects of unitary evolution of general states for a multilevel quantum system by exploiting the structure of coadjoint orbits in the unitary group Lie algebra. Using the same method in the case of SU(3) we study the effect of degeneracies on geometric phases for three-level systems. This is shown to lead to a highly nontrivial generalization of the result for two-level systems in which degeneracy results in a "monopole" structure in parameter space. The rich structures that arise are related to the geometry of adjoint orbits in SU(3). The limiting case of a two-level degeneracy in a three-level system is shown to lead to the known monopole structure.Comment: Latex, 27 p

Effect of ranolazine on HbA1c and blood glucose levels in diabetic patients with chronic angina

Background: Diabetes mellitus is the fifth leading cause of death worldwide and is one of the common co-morbid conditions associated with coronary artery disease (CAD). The overall prevalence of CAD is 7.4% but the prevalence of CAD in diabetics is 9%. Hence treatment of hyperglycemia is a key goal of secondary preventive therapy with a target of reducing HbA1c to <7%. The risk of CAD has been reported to occur 2 to3 decades prior in diabetics compared to non-diabetics. Hence discovery of drugs with potential role in both diabetes and CAD seems to be necessary. Ranolazine is a novel oral anti anginal drug known to reduce HbA1c and fasting blood glucose levels in angina patients with diabetes. The objective of this study is to show the effect of ranolazine (antianginal drug) on HbA1c and fasting blood glucose levels in diabetic patients with chronic angina.Methods: Patients were divided into: Group 1 continued with previous antidiabetic drugs and antianginal drugs. Group 2 were prescribed Tab ranolazine 1000mg b.d (orally) as add on therapy along with previous antidiabetic drugs and antianginal drugs.Results: There was a significant reduction in HbA1c and FBS levels in Group 2 patients who were on ranolazine. Reduction of HbA1c in group1 and Group 2 was 0.21±0.65% and 1.30±1.16% respectively. Reduction of FBS in group1 and group2 was 10.66±27.80mg/dl and 29.97±31.49mg/dl respectively.Conclusions: From the present study we can conclude that ranolazine, an antianginal drug when given at a dose of 1000mg bd in diabetic patients with chronic angina reduces HbA1c and FBS levels.

Numerical Study of Pulse Detonation Engine with One-step Overall Reaction Model

This paper presents an insight for the study of transient, compressible, intermittent pulsed detonation engine with one-step overall reaction model to reduce the computational complexity in detonation simulations. Investigations are done on flow field conditions developing inside the tube with the usage of irreversible one-step chemical reactions for detonations. In the present simulations 1-D and 2-D axisymmetric tubes are considered for the investigation. The flow conditions inside the detonation tube are estimated as a function of time and distance. Studies are also performed with different grid sizes which influence the prediction of Von-Neumann spike, CJ Pressure and detonation velocity. The simulation result from the single-cycle reaction model agrees well with the previous published literature of multi-step reaction models. The present studies shows that one-step overall reaction model is sufficient to predict the flow properties with reasonable accuracy. Finally, the results from the present study were compared and validated using NASA CEA.Defence Science Journal, Vol. 65, No. 4, July 2015, pp. 265-271, DOI: http://dx.doi.org/10.14429/dsj.65.873

Squeezing of a coupled state of two spinors

The notion of spin squeezing involves reduction in the uncertainty of a component of the spin vector below a certain limit. This aspect has been studied earlier for pure and mixed states of definite spin. In this paper, this study has been extended to coupled spin states which do not possess sharp spin value. A general squeezing criterion has been obtained by requiring that a direct product state for two spinors is not squeezed. The squeezing aspect of entangled states is studied in relation to their spin- spin correlations.Comment: Typeset in LaTeX 2e using the style iopart, packages iopams,times,amssymb,graphicx; 17 pages, 5 eps figure file

Parametric analysis of Asymmetric Spur Gear Tooth

Abstract Gear is a machine element used to transmit motion and power between rotating shafts by means of progressive engagement of projections called teeth. Gears are classified according to the relative position of the axes of the shaft, type of gearing, peripheral velocity of the gears and position of teeth on gear surface. Presently gears are suffered by backlash the amount by which the width of a tooth space exceeds the thickness of the engaging tooth on the pitch circles, undercut a condition in generated gear teeth when any part of the fillet curve lies inside of a line drawn tangent to the working profile at its lowest point and interference is an important aspect of kinematics of gearing. When the gear tooth tries to dig below the base circle of mating gear then the gear tooth action shall be non conjugate and violate the fundamental law of gearing this non conjugate action is called the interference . These defects can be eliminated by increasing the pressure angle, by increasing the addendum of mating gear and another way of increasing the load capacity of transmissions is to modify the involute geometry. This has been a standard practice in sophisticated gear design for many years. The nomenclature describing these types of gear modifications can be quite confusing with reference to addendum modification or profile shift. An additional alteration that is very rarely used is to make the gears asymmetric with different pressure angles for each side of the tooth. An asymmetric spur gear drive means that larger and smaller pressure angles are applied for the driving and coast sides. The two profiles of a gear tooth are functionally different for most gear drives. The workload on one side of profile is significantly higher than the other Gears. The main objective of this paper is to generate asymmetric spur gear tooth geometry for different pressure angles on drive and coast side using computer programme. Developed programme is used to create a finite element model of gear tooth to study the effect of bending stress at the critical section for different pressure angles, different number of teeth and module. To study the effect of above asymmetric spur tooth parameters Finite Element Analysis software ANSYS was used

A UNIQUE MODULATOR FOR BOOST REGULATOR TO REDUCE THE VOLTAGE STRESS

The APS control can be used to lessen the current force on switches see how to avoid load as the traditional interleaving control can be used to help keep better performance in heavy load. This paper looks into a manuscript pulse width modulation (PWM) plan for 2-phase interleaved boost ripper tools with current multiplier for fuel cell power system by mixing alternating phase shift (APS) control and traditional interleaving PWM control. To be able to reduce output fuel cell stack output current ripple or even the electricity/electricity ripper tools input current ripple, whether passive filter or active filter may be used, however, this will raise the complexity from the system. The boundary condition for swapping between APS and traditional interleaving PWM control comes. In line with the aforementioned analysis, a complete power range control mixing APS and traditional interleaving control is suggested. Loss breakdown analysis can also be given look around the efficiency from the ripper tools. Finally, it's verified by experimental results. The whole process of a switching cycle from the ripper tools could be split into six stages at boundary condition that the current force on switch is going to be bigger than 1 / 2 of the output current with traditional interleaving control