2,815 research outputs found
Evaluating the performance of Netfilter architecture in Private Realm Gateway.
Network address translation(NAT) was introduced to decelerate the IPv4 ad- dresses depletion through separation of a network into the public and private realm. The hosts in a private network connect to the public Internet by sharing a pool of public IP addresses, and NAT acts as a gateway between the public and the private networks. Although NAT alleviates the problem of addresses deple- tion, it leads to a reachability problem as NAT would generally block any outside connections to the private network from the Internet.
This thesis examines a new concept called Private Realm Gateway(PRGW) which is developed to overcome the shortcoming of NAT. PRGW imitates the NAT func- tionality and allows the inbound connections initiated from the public networks towards a private realm via the Circular Pool of Public Addresses (CPPA). PRGW provides interoperability between the legacy IP network and hosts in the private networks and vice-versa, using pre-existing TCP/IP protocols and applications.
PRGW has been implemented on top of Linux operating system, and therefore, the primary approach in this thesis is to evaluate the forwarding performance of Linux kernel networking (Netfilter subsystem), as well as inspect the possible performance tuning methods to achieve higher packets processing rates.
The performance of Netfilter is evaluated by offering heavy traffic load to measure packet forwarding capability, memory usage by IP traffic as well as overloading the CPU process. In addition, the stateful mechanism for packet filtering and NAT routing was evaluated using appropriate iptables lookup and packets traversing through different chains. When conducting the various tests, by adjusting different parameters in Linux Netfilter subsystem revels that the PRGW can be deployed over the Linux architecture
Karyomorphology of skin diseases in human population
The aim of the present study is to determine the incidence of chromosomal abnormalities in skin diseases. Patients were analyzed for chromosomal aberrations using peripheral lymphocyte culture. Cytogenetic analysis was carried out in 27 people affected by Vitiligo, Psoriasis, Parthenia. Lymphocytes culture was done and subjected to colcemid, hypotonic treatment, fixation and air drying. GTG banded chromosomes were identified and counted for abnormalities. One way ANOVA was used to analyze the collected data. Tukey-Kramer Multiple Comparisons Test was used to determine differences between the means. Comparing the groups on the basis of type of chromosomal abnormalities, the differences between the means was found to be non significant (P>0.05) in all the comparisons. However, it was found to be significant for acrocentric association in Vitiligo subjects as compared to the controls. The means for premature centromeric divisions (Parthenia Vs Vitiligo) were also found to be significantly different
Plasma Electrophoresis and Phagocytic Index Screening of Some Indigenous Vegetables Subjected to Preclinical Models
50 % of methanolic extract Colocasia esculenta, Moringa oliefera, Luffa cylindrica, and Hibiscus esculentus were subjected to immunomodulatory activity in Swiss albino mice either sex. Mice were treated with five days of dosing of Colocasia esculenta 50 mg/kg bw, Colocasia esculenta 100 mg/kg bw, Moringa oliefera 200mg/kg bw, Moringa oleifera 400 mg/kg bw, Luffa cylindrica 100 mg/kg bw, Luffa cylindrica 200 mg/kg bw, Hibiscus esculentus 100 mg/kg bw, and Hibiscus esculentus 200 mg/kg bw. Cyclosporine (2.5 mg/kg) used as a standard reference drug for 5 days. Investigation of immunomodulator activity of these 50 % of methanolic extract of drugs to parentage of yeast digestion form 24 hours the peritoneal fluid culture and electrophoretic plasma protein band albumin, alpha 1, alpha 2, beta and gamma respectively from blood plasma were observed using parameters phagocytosis and plasma electrophoresis. Also investigated the ulcerogenic effect or any toxic effect of plant extract by histopathology study of crypt, villi and goblet cells with reference to standard drug cyclosporine. As regards these parameters, Hibiscus esculentus 100 and 200 mg/ kg bw dose, Moringa oleifera 200 and 400 mg/ kg bw dose and Luffa cylindrica 200mg/kg bw elicited a moderately significant increase in the % of yeast digestion (P < 0.001) respectively and Luffa cylindrica 100mg/kg bw significant increase in the % of yeast digestion (P < 0.01). Hibiscus esculentus showed significant dose dependent increase and Moringa oleifera decrease phagocytic activity of macrophages. Hibiscus esculentus 200 mg/ kg bw dose and Moringa oleifera 200 significantly increased (P < 0.01) the Gamma globulin.However, our present study revealed and signatured for their immunomodulator enhancing property. As in Asian subcontinent daily there vegetables are cooked and served with know and unknown of its potential function against different diseases. If there vegetables properly ruled out for their pharmacological aspect then it may add diamond in the crown of dietician which has been bother every day today life but over looked exponetentially.Keywords:- Colocasia esculenta, Moringa oliefera, Luffa cylindrica, and Hibiscus esculentu
Case Study on Resolving High Vibration Issue of a Centrifugal Compressor at an Offshore Platform
Case StudiesGas Injection Compressors are critical for offshore oil production facilities. A compressor downtime lowers oil production. This case study is about a Gas Injection Compression train at an offshore platform in the Middle East. This case study focuses on how the gradual increase in vibrations was successfully diagnosed, pinpointing the root cause for the high vibration, and finally how it was resolved. The Compression train is equipped with an online vibration monitoring and protection system in addition to a condition monitoring software that was used to diagnose the issue
A survey of MPI related debuggers and tools
technical reportMessage Passing Interface is a widely used standard in the High Performance and Scienti c Computing Community for writing programs that can exploit the capability of parallel platforms. However, the inherent complexity and the size of the communication standard have made it difficult for programmers to use it efficiently and more importantly correctly. There are numerous tools and debuggers written by various academic/industry communities to nd bugs in the MPI programs written by users. Some of them are MPI-CHECK (Iowa state Univ, [12]), MPIDD (UNBC, Canada [6]), UMPIRE (LLNL, [15]), Intel Message Checker (Intel, [5]), MARMOT (HLRS, [8]) and TotalView ([1]). A brief analysis and comparison of these tools are presented below. In addition, this report presents an overview of the debugging support build into some of the currently popular MPI libraries
Three Dimensional Pseudo-Spectral Compressible Magnetohydrodynamic GPU Code for Astrophysical Plasma Simulation
This paper presents the benchmarking and scaling studies of a GPU accelerated
three dimensional compressible magnetohydrodynamic code. The code is developed
keeping an eye to explain the large and intermediate scale magnetic field
generation is cosmos as well as in nuclear fusion reactors in the light of the
theory given by Eugene Newman Parker. The spatial derivatives of the code are
pseudo-spectral method based and the time solvers are explicit. GPU
acceleration is achieved with minimal code changes through OpenACC
parallelization and use of NVIDIA CUDA Fast Fourier Transform library (cuFFT).
NVIDIAs unified memory is leveraged to enable over-subscription of the GPU
device memory for seamless out-of-core processing of large grids. Our
experimental results indicate that the GPU accelerated code is able to achieve
upto two orders of magnitude speedup over a corresponding OpenMP parallel, FFTW
library based code, on a NVIDIA Tesla P100 GPU. For large grids that require
out-of-core processing on the GPU, we see a 7x speedup over the OpenMP, FFTW
based code, on the Tesla P100 GPU. We also present performance analysis of the
GPU accelerated code on different GPU architectures - Kepler, Pascal and Volta
Tuning phase-stability and short-range order through Al-doping in (CoCrFeMn)100-xAlx high entropy alloys
For (CoCrFeMn)Al high-entropy alloys, we investigate the
phase evolution with increasing Al-content (0 x 20 at.%). From
first-principles theory, the Al-doping drives the alloy structurally from FCC
to BCC separated by a narrow two-phase region (FCC+BCC), which is well
supported by our experiments. We highlight the effect of Al-doping on the
formation enthalpy and electronic structure of (CoCrFeMn)Al
alloys. As chemical short-range order (SRO) in multicomponent alloys indicates
the nascent local order (and entropy changes), as well as expected
low-temperature ordering behavior, we use thermodynamic linear-response within
density-functional theory to predict SRO and ordering transformation and
temperatures inherent in (CoCrFeMn)Al. The predictions agree
with our present experimental findings, and other reported ones.Comment: 27 pages, 9 figures, 1 tabl
Fighting Cybercrime with Zero Trust
Zero Trust Architecture focuses on securing critical data and access paths by eliminating trust as much as possible by “assuming breach.” It establishes trust every time a user tries to access an asset in the system by questioning the premise that users, devices, and network components should be implicitly trusted based on their location within the network. We have chosen Zero Trust to help reduce the impact of cybercrime and establish baseline security practices. It is a dramatic paradigm shift in the philosophy of securing our infrastructure, networks, and data, from verifying once at the perimeter to continually verifying each user, device, application, and transaction. Trust in humans is essential to forming connections; however, trust in network connections can create dangers and potential security gaps in the digital world. In a hyper-connected world, anyone can launch an attack virtually and participate in cybercrime by violating the trust of systems or networks. The cost of not implementing good security practices is evident in the growing number of data breaches and ransomware attacks that erode consumers' trust in tech and online space. Considering Zero Trust and Zero Trust Architecture developed by the National Institute of Standards and Technology (NIST) should help reduce the impact of cybercrime and protect the crown jewels in cyberspace from a malicious insider or an external attacker
Expanding the repertoire of pyrrolidyl PNA analogues for DNA/RNA hybridization selectivity: aminoethylpyrrolidinone PNA (aepone-PNA)
New PNA analogues derived from aminoethylpyrrolidin- 5-one backbone show stabilization of aepone-PNA:DNA hybrids and destabilization of the corresponding RNA hybrids compared to unmodified PNA
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