LC-PCN: The Load Control PCN Solution

There is an increased interest of simple and scalable resource provisioning solution for Diffserv network. The Load Control PCN (LC-PCN) addresses the following issues:\ud o Admission Control for real time data flows in stateless Diffserv Domains\ud o Flow Termination: Termination of flows in case of exceptional events, such as severe congestion after re-routing.\ud Admission control in a Diffserv stateless domain is a combination of:\ud o Probing, whereby a probe packet is sent along the forwarding path in a network to determine whether a flow can be admitted based upon the current congestion state of the network\ud o Admission Control based on data marking, whereby in congestion situations the data packets are marked to notify the PCN-egress-node that a congestion occurred on a particular PCN-ingress-node to PCN-egress-node path.\ud \ud The scheme provides the capability of controlling the traffic load in the network without requiring signaling or any per-flow processing in the PCN-interior-nodes. The complexity of Load Control is kept to a minimum to make implementation simple.\u

What is the probability that a random integral quadratic form in nn variables has an integral zero?

We show that the density of quadratic forms in $n$ variables over $\mathbb Z_p$ that are isotropic is a rational function of $p$, where the rational function is independent of $p$, and we determine this rational function explicitly. When real quadratic forms in $n$ variables are distributed according to the Gaussian Orthogonal Ensemble (GOE) of random matrix theory, we determine explicitly the probability that a random such real quadratic form is isotropic (i.e., indefinite). As a consequence, for each $n$, we determine an exact expression for the probability that a random integral quadratic form in $n$ variables is isotropic (i.e., has a nontrivial zero over $\mathbb Z$), when these integral quadratic forms are chosen according to the GOE distribution. In particular, we find an exact expression for the probability that a random integral quaternary quadratic form has an integral zero; numerically, this probability is approximately $98.3\%$.Comment: 17 pages. This article supercedes arXiv:1311.554

Mechanisms of rolling contact spalling

The results of a study aimed at analyzing the mechanical material interactions responsible for rolling contact spalling of the 440 C steel, high pressure oxygen turbopump bearings are presented. A coupled temperature displacement finite element analysis of the effects of friction heating under the contact is presented. The contact is modelled as a stationary, heat generating, 2 dimensional indent in an elastic perfectly plastic half-space with heat fluxes up to 8.6 x 10000 KW/m sq comparable to those generated in the bearing. Local temperatures in excess of 1000 C are treated. The calculations reveal high levels of residual tension after the contact is unloaded and cools. Efforts to promote Mode 2/Mode 3 fatigue crack growth under cyclic torsion in hardened 440 C steel are described. Spalls produced on 440 C steel by a 3 ball/rod rolling contact testing machine were studied with scanning microscopy. The shapes of the cyclic, stress strain hysteresis loops displayed by hardened 440 C steel in cyclic torsion at room temperature are defined for the plastic strain amplitudes encountered in rolling/sliding contact. Results of these analyses are discussed in detail

3 Dimensional Virtual Modelling of Human Femur Bone with Prosthetic Plate and Screws

Femur bone is the longest and stronger bone in the human body. This bone is contained a linear-elastic, isotropic and homogeneous material of calcium phosphate. It needs to support maximum weight of the body in between hip joint and knee joint during different mode of body posture. Firstly 3 dimension geometric model of femur bone, prosthetic plate and screw is generated in Solid works CAD software which seems to define high mode of difficulty for generating the bone model. The objective of femur bone CAD model is identified the maximum stresses and deformation zone by applying the static load into the finite element ANSYS software. Further femur bone is provided a single crack at maximum stressed zone implanted with prosthetic bone plate and screws

Antimicrobial sensitivity pattern of gram positive CSF isolates in children with septic meningitis in a Tertiary Care Hospital

The present study was conducted with the objective to determineantimicrobial susceptibility of Gram positive CSF isolates in septic meningitis in a tertiary care hospital. CSF (3-5 ml) was collected from 638 admitted children clinically suspected of septic meningitis. Bacterial isolates were identified and microbial sensitivity was assessed by the Kirby-Bauer’s disk diffusion method. Of the samples tested 102 (15.99%) were culture positive of which 45 (44.12%) culture positives were found inchildren aged 1-12 years. M: F ratio was 1.62:1. Maximum incidence (51 cases) was in summer-rainy season and in institutional delivery (58 cases). Primary immunization did not protect against septic meningitis. The isolates in 66 (64.71%) cases were Gram positive of which 36 (54.55%) were Streptococcus spp., 24 (36.36%) Staphylococcus aureus and 6 (9.09%) cases coagulase negative Staphylococcus (CONS). Both Streptococci and coagulase negative Staphylococci were highly sensitive (100%) to Linezolid, Vancomycin and Piperacillin-Tazobactam. However, Staphylococcus aureus were 100% sensitive to Linezolid and Vancomycin but were only 87.5% sensitive to Piperacillin-Tazobactam combination. The Streptococcus species showed a high degree of resistance to Tetracyclin91.67%, Co-trimoxazole 88.89% and Penicillin 63.89%. Staphylococcus aureus showed resistance to the tune of 83.33% each to Tetracycline and Co-trimoxazxole and 79.17% with Penicillin. In case of coagulase negative Staphylococcus, Co-trimoxazole showed resistance in 83.33%, Penicillin in 66.67% and Tetracycline in 50% cases. In septic meningitis Gram positive isolates predominate. Therapy should be based on trends of bacterial sensitivity

Stabilization of anarobic digestor sludge through vermicomposting

In this study, efficiency of vermitechnology in stabilizing sludge without pre-treatment was studied. The sludge was directly introduced in the vermicomposting reactors after their withdrawal from the bio-methanation reactor installed for experimentation on domestic waste. One Liter (5% TS) sludge was loaded after every fourth day and it was discontinued after sixteen days. However, the chemical analysis of the compost was done till twentyfourth day. The present study also evaluated the potential of one indigenous Perionyx excavates (P.e.) and one exotic epigeic earthworm species Eisenia fetida (E.f). The results clearly elucidate that vermireactor with indigenous earthworms (P.e) gives over all comparable similar results with world wide known exotic species (E.f). The results of the study show a significant reduction in initial C/N ratio from an initial value of 19 to 9 for all reactors with earthworms, total organic matter (TOC) reduced by 50% and pH also reduced nearer to neutral, but increase in, total nitrogen (TN) 95%, NH4+-N reduced from 0.52% to 0.31% and NO3-N increased from 0 to 0.13%, total phosphorus (TP) increased from the initial concentration of 0.76% to 1.31%., However, removal efficiency of Fecal coliforms (indicator organism) in the prepared vermicompost through P.e and E.f was in the 6 log and 7 log (MPN/gm) respectively