Towards a path integral for the pure-spin connection formulation of gravity

A proposal for the path-integral of pure-spin-connection formulation of gravity is described, based on the two-form formulation of Capovilla et. al. It is shown that the resulting effective-action for the spin-connection, upon functional integration of the two-form field $\Sigma$ and the auxiliary matrix field $\psi$ is {\it non-polynomial}, even for the case of vanishing cosmological constant and absence of any matter couplings. Further, a diagramatic evaluation is proposed for the contribution of the matrix-field to the pure spin connection action.Comment: 8 pages in plain-TeX.-----IUCAA_TH/9

Structural, optical and nanomechanical properties of (1 1 1) oriented nanocrystalline ZnTe thin films

Structural, optical and nanomechanical properties of nanocrystalline Zinc Telluride (ZnTe) films of thickness upto 10 microns deposited at room temperature on borosilicate glass substrates are reported. X-ray diffraction patterns reveal that the films were preferentially oriented along the (1 1 1) direction. The maximum refractive index of the films was 2.74 at a wavelength of 2000 nm. The optical band gap showed strong thickness dependence. The average film hardness and Young’s modulus obtained from loaddisplacement curves and analyzed by Oliver-Pharr method were 4 and 70 GPa respectively. Hardness of (1 1 1) oriented ZnTe thin films exhibited almost 5 times higher value than bulk. The studies show clearly that the hardness increases with decreasing indentation size, for indents between 30 and 300 nm in depth indicating the existence of indentation size effect. The coefficient of friction for these films as obtained from the nanoscratch test was ∼0.4.Financial support in the form of fellowships to MSRNK and SK from the ACRHEM project of DRDO is acknowledged

Momentum space properties from coordinate space electron density

Electron density and electron momentum density, while independently tractable experimentally, bear no direct connection without going through the many-electron wave function. However, invoking a variant of the constrained-search formulation of density functional theory, we develop a general scheme (valid for arbitrary external potentials) yielding decent momentum space properties, starting exclusively from the coordinate space electron density. Numerical illustration of the scheme is provided for the closed-shell atomic systems He, Be and Ne and for $1s^1~2s^1$ singlet electronic excited state for Helium by calculating the Compton profiles and the $$ expectation values derived from given coordinate space electron densities.Comment: 4 pages, 1 figur

AN APPROACH FOR FAULT DETECTION AND FAULT MANAGEMENT IN THE WIRELESS SENSOR NETWORK TO EXTEND NETWORK LIFETIME

A mobile wireless ad hoc sensor network (MANET) consists of a group of homogeneous or heterogeneous mobile communicating hosts that form an arbitrary network interconnected via by means of several wireless communication media without any fixed infrastructure. In such network the delivery of the data packet from source to destination may fail for various reasons and major due to failure-prone environment of networks. This may happens due to the topology changes, node failure due to battery exhaust, failure of the communication module in the wireless node and results in the link failure. This paper addressed the major problem of link failure in the WSN and with the aim of providing robust solution so as to satisfy the stern end-to-end requirements of QoS-based communication networks. In this paper we modifies existing fully distributed cluster-based routing algorithm by addressing local recovery for the link failure. Performance of this new fault-tolerant fully distributed cluster-based routing algorithm is evaluated by simulating it in NS2 environment and we show that it performs better than the existing algorithm and provide better solution for fault detection and fault management along the QoS paths

AN APPROACH FOR FAULT DETECTION AND FAULT MANAGEMENT IN THE WIRELESS SENSOR NETWORK TO EXTEND NETWORK LIFETIME

A mobile wireless ad hoc sensor network (MANET) consists of a group of homogeneous or heterogeneous mobile communicating hosts that form an arbitrary network interconnected via by means of several wireless communication media without any fixed infrastructure. In such network the delivery of the data packet from source to destination may fail for various reasons and major due to failure-prone environment of networks. This may happens due to the topology changes, node failure due to battery exhaust, failure of the communication module in the wireless node and results in the link failure. This paper addressed the major problem of link failure in the WSN and with the aim of providing robust solution so as to satisfy the stern end-to-end requirements of QoS-based communication networks. In this paper we modifies existing fully distributed cluster-based routing algorithm by addressing local recovery for the link failure. Performance of this new fault-tolerant fully distributed cluster-based routing algorithm is evaluated by simulating it in NS2 environment and we show that it performs better than the existing algorithm and provide better solution for fault detection and fault management along the QoS paths

Design of 8 and 16 Bit LFSR with Maximum Length Feedback Polynomial & Its pipelined Structure Using Verilog HDL

This paper is mainly concerned with the design of random sequences using Linear Feedback Shift Register (LFSR). This pseudo sequences is mainly used for various communication purposes. The other application such as banking, cryptographic, encoder & decoder. For hardware prototype FPGA is used because of its flexibility to reconfigure design many times. LFSR is a shift register whose output random state depends upon feedback polynomial. But by using pipelined architecture we can reduce the timing of random pattern generated at output by reducing the critical path. It can count maximum 2n-1 states and produce pseudo-random number at the output. Finally, comparing the simple and pipelined architecture of 8 & 16-bit LFSR

Comparative Study of Laparoscopic Cholecystectomy Techniques: Traditional Clipping versus Harmonic Scalpel Closure

Background: Laparoscopic cholecystectomy (LC), a widely used surgical procedure to remove the gallbladder, can vary in how the cystic duct and artery are closed. This study compared the safety and effectiveness of LC performed using the standard method (TM) with LC performed with harmonic scalpel assistance (HLC). Methods: A prospective comparison research with 30 patients in each group (LC and HLC) of 60 patients scheduled for LC was conducted. The length of the hospital stays, the number of antibiotics used, the number of surgical problems, postoperative bile leakage, and the length of the operation were all recorded. Suitable tests were used in the statistical analysis. Results: When compared to LC, HLC showed considerably shorter operating times (35.1 4.079 vs. 47.933 8.026 minutes, p0.0001) and less frequent need for antibiotics (3.267 0.691 vs. 4.367 0.809 days, p0.0001). Surgery-related complications were comparable between groups (LC 10% vs. HLC 6.67%, p=0.549). Postoperative bile leakage in HLC (0%) were trending lower than LC (6.67%, p=0.157). A shorter hospital stay was the result of HLC (3.1 + 0.547 vs. 4.4 + 0.855 days, p0.0001). Conclusion: In comparison to LC, HLC offers benefits such as faster recovery times, less need for antibiotics, and shorter hospital stays. Although there were no appreciable differences in postoperative problems in HLC, there was a tendency towards less intraoperative complications. These results back up the use of HLC as a secure and effective cholecystectomy option. It is need to do additional study with larger cohorts and longer follow-up