Percus-Yevick and Hypernetted-Chain Approximations

Percus-Yevick and hypernetted-chain models connecting the structure factor S(k) with effective pair potential φ(r) have been studied in detail. Recent neutron-scattering data of Yarnell et al., for liquid argon at 85°K, have been employed to generate these potentials. Using 0.01 uncertainty in the experimental data, the uncertainty in the pair potentials has been computed. Having developed a general method of error propagation analysis, the effect of experimental errors in S(k) on Percus-Yevick and hypernetted-chain potentials is investigated and the resulting potentials are compared with Lennard-Jones and Barker, Fisher, and Watts potentials

Incident Response Process Guidelines -For Information Security Management

ABSTRACT Attacks on information systems and networks have become more numerous, sophisticated, and severe in recent years. New types of securityrelated incidents emerge more frequently. While preventing such attacks would be the ideal course of action for organizations, not all information system security incidents can be prevented. Every organization that depends on information systems and networks to carry out its mission should identify and assess the risks to its systems and its information and reduce those risks to an acceptable leve

Administrator and Fidelity Based Secure Routing (AFSR) Protocol in MANET

The proliferation of mobile computing and communication devices are driving a revolutionary change in our information society. Among all the applications and services run by mobile devices, network connections and corresponding data services are without doubt the most demanded services by mobile users. A MANET is a continuously self-configuring, infrastructure-less network of mobile devices connected without wires, which makes it ideal for the present scenario. But, due to lack of any centralized infrastructure and access to trusted authorities, the security in MANET poses a huge threat. The prominent routing protocols we know are generally designed for environments where the nodes within a network are non-malicious. Due to the vulnerable nature of the mobile ad hoc network, there are numerous security threats that disturb its development. We propose a protocol for MANETs named “Administrator and Fidelity Based Secure Routing Protocol” (AFSR), which ensures secure routing through the network: by electing an Administrator node on the basis of Willingness and Fidelity, after which a node only communicates to that secure Admin node. This selection of secured admin nodes results in mitigation of various threats. We have evaluated our proposed protocol by simulating and comparing in GloMoSim

Immediate induction of labor in premature rupture of membranes at term (PROMT)-vaginal Misoprostol tablet versus PGE2 gel: a randomized comparative study

Background: The aim of the study is to compare immediate induction with vaginal misoprostol tablet and immediate induction with vaginal PGE2 gel in women with premature rupture of membranes at term (PROMT).Methods: Nine hundred thirty-two women with PROM at term were assigned randomly to receive intravaginal 25μg misoprostol tablet, 4 hourly with a maximum of 5 doses or 0.5 mg vaginal PGE2 gel 6 hourly with a maximum of 2 doses. The primary outcome measures were cesarean section rate, admission to delivery interval and induction to delivery interval. Secondary outcomes included, mode of delivery, and maternal and neonatal safety outcome. Results were calculated applying Fisher Exact Test, Chi square test, t test and calculating the P-value using an alpha level of 0.05 for Type I error.Results: The mean time from admission to delivery was 13.16 hours in the misoprostol group and 13.56 hours in the PGE2 group (P= 0.3014). Induction to delivery interval was also comparable between the groups (10.23 h versus 10.18 h).Caesarean section rate did not differ significantly between groups (12.13% versus 15.74% ,P=0.135 RR 0.783 95% CI 0.568-1.079).More women in misoprostol group had instrumental delivery (7.57% versus 4.25%, P=0.031, RR 1.089 95% CI 1.04-3.03).The  neonatal outcomes were comparable between the groups . Maternal outcomes were not significantly different except incidence of analgesic use (P=0.009 RR 1.62 95% CI 1.03-1.30), meconium stained liquor (P=.0096 RR 2.03 CI 1.17-3.53) and   number of digital vaginal examinations (P<.0001) in misoprostol group.Conclusions: Vaginal misoprostol is equally efficacious in labor induction and demonstrates a similar fetal and maternal safety profile to PGE2 gel

Collective Properties of X-ray Binary Populations of Galaxies. I. Luminosity and Orbital Period Distributions of High-Mass X-ray Binaries

We introduce a method for obtaining the X-ray luminosity function (XLF) and the binary-period distribution of populations of high-mass X-ray binaries (HMXBs) in the stellar fields (i.e. outside globular clusters) of normal galaxies. We start from standard distributions of the parameters of those primordial binaries which are the progenitors of HMXBs, and follow the transformation of these ditributions with the aid of a Jacobian formalism as the former evolve into the latter through the processes of the first mass transfer and the supernova (SN) that follows. We discuss the distributions of the post-SN binaries and the HMXBs. We show that our calculated model XLF has a differential slope $\approx -1.6$ with a flattening at low luminosities, in excellent agreement with observations. The calculated binary-period distribution, which basically has a slightly sloping plateau-like character at intermediate periods, with a rise to this plateau at shorter periods and fall-off from it at longer periods, is in agreement with the observed distribution within observational uncertainties. We discuss the physical origin of these distributions. We demonstrate that, while the effects of both (a) the distribution of the properties of the massive companion in the HMXBs, and (b) the primordial orbital distribution and the SN dynamics are important, the former appear to be dominant in determining the XLF, and the latter in determining the HMXB binary-period distribution. We discuss the possible roles of stellar-mass black holes and ultra-luminous X-ray sources (ULX) in the observed "universal" XLF of HMXBs.Comment: Accepted for publication in Ap

Simulating Descent and Landing of a Spacecraft

The Dynamics Simulator for Entry, Descent, and Surface landing (DSENDS) software performs high-fidelity simulation of the Entry, Descent, and Landing (EDL) of a spacecraft into the atmosphere and onto the surface of a planet or a smaller body. DSENDS is an extension of the DShell and DARTS programs, which afford capabilities for mathematical modeling of the dynamics of a spacecraft as a whole and of its instruments, actuators, and other subsystems. DSENDS enables the modeling (including real-time simulation) of flight-train elements and all spacecraft responses during various phases of EDL. DSENDS provides high-fidelity models of the aerodynamics of entry bodies and parachutes plus supporting models of atmospheres. Terrain and real-time responses of terrain-imaging radar and lidar instruments can also be modeled. The program includes modules for simulation of guidance, navigation, hypersonic steering, and powered descent. Automated state-machine-driven model switching is used to represent spacecraft separations and reconfigurations. Models for computing landing contact and impact forces are expected to be added. DSENDS can be used as a stand-alone program or incorporated into a larger program that simulates operations in real time

A stochastic frontier approach to modelling financial constraints in firms:an application to India

We propose the use of stochastic frontier approach to modelling financial constraints of firms. The main advantage of the stochastic frontier approach over the stylised approaches that use pooled OLS or fixed effects panel regression models is that we can not only decide whether or not the average firm is financially constrained, but also estimate a measure of the degree of the constraint for each firm and for each time period, and also the marginal impact of firm characteristics on this measure. We then apply the stochastic frontier approach to a panel of Indian manufacturing firms, for the 1997–2006 period. In our application, we highlight and discuss the aforementioned advantages, while also demonstrating that the stochastic frontier approach generates regression estimates that are consistent with the stylised intuition found in the literature on financial constraint and the wider literature on the Indian credit/capital market