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81.
This work models the INL ZPR-6/7 assembly employing two different approaches: a probabilistic approach using MCNP/5 and a deterministic one using MC2-2/REBUS. With MCNP/5, each drawer of the assembly is modeled in detail with regard to geometry and fuel loading. In the deterministic approach, the MC2-2 collapses cross-sections in energy and space into a 15 few group structure homogenized spatially over each drawer for the REBUS 3D model. Various reactivity coefficients and reaction rates at different locations inside the core were evaluated and compared for both approaches and contrasted to published experimental data and were found to be in good agreement. 相似文献
82.
World Wide Web - Internet of things (IoT) have entirely revolutionized the industry. However, the cyber-security of IoT enabled cyber-physical systems is still one of the main challenges. The... 相似文献
83.
Masoumeh Tabatabaee Atefeh Gholamighavamabad Elaheh Khabiri Masood Parvez 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(3):627-633
Two novel three-dimensional coordination polymers, formulated as {[M2(μ-C4H4O6)2(H2O)] · 3H2O}∞ (M = Mn for 1 and Cd for 2), have been synthesized under hydrothermal reaction condition. Both complexes were characterized by elemental analysis and IR spectroscopy. Their molecular and crystal structures were determined by X-ray crystal structure analysis and their thermal stability by TGA-DTA methods. Compound 1 crystallizes in the monoclinic space group, P21, while compound 2 crystallizes the orthorhombic space group, P212121. The structures are self-assembled from bifunctional tartrate and water molecules. Tartrate ligands in 1 and 2 contribute to both covalent and hydrogen bonds. Polymeric chains of 1 and 2 are composed of M(II) ions bridged by tartrate ions in O,O′ fashion. The asymmetric units of coordination polymers contain two metal centers having different coordination environments. 相似文献
84.
Ijaz Ahmad Faqir Muhammad Anjum Masood Sadiq Butt Muhammad Issa Khan 《International Journal of Food Properties》2013,16(2):310-320
Spring wheat varieties were subjected to physico-chemical, mixographic and amino acid analysis. The data obtained was subjected statistically analyzed. The cluster analysis classification based on centroid method indicated that for lysine and overall cookie scores, generally most wheat varieties fell in one group, while for total chapati score most of the wheat varieties were classified into two groups. The wheat varieties falling in same cluster group have similarities in respect of lysine, chapati and cookie quality. This indicated that wheat varieties in Pakistan have narrow ranges of spectrum in their genetic make up for their quality attributes. However, some wheat varieties were distinguished into different groups having a wide distance range especially Shahkar 95 for lysine content, LU 26 and Punjab 96 for cookie quality and Punjnad 88 in case of chapati quality. The present grouping suggests that wheat varieties in cluster group with wider range for lysine content may be used further in a hybridization program to improve the nutritional quality of wheat. 相似文献
85.
Muhammad Abrar Faqir Muhammad Anjum Masood Sadiq Butt Imran Pasha Muhammad Atif Randhawa Farhan Saeed 《Critical reviews in food science and nutrition》2013,53(8):862-874
Food contagion with aflatoxins is the modern concern and has received a great awareness during the last few decades. The intermittent incidence of these toxins in agricultural commodities has negative role on the economy of the affected regions where harvest and postharvest techniques for the prevention of mold growth, are seldom practiced. Aflatoxins are difuranocoumarin derivatives produced by a polyketide pathway by the fungus Aspergillus flavus and Aspergillus parasiticus via polyketide pathway which are highly hepatotoxic, hepatocarcinogenic, teratogenic, and mutagenic in nature and contaminate a wide variety of important agricultural commodities before, during, and after harvest in various environmental conditions. The production of aflatoxins in innate substrates depends upon the various factors, that is, type of substrate, fungal species, moisture contents of the substrate, minerals, humidity, temperature, and physical damage of the kernels. These toxins cause several ailments such as cancer, hepatitis, mutation abnormalities, and reproduction disorders. Minimization and inactivation of aflatoxins contaminants through proper crop management at farm level and with physical, chemical, and biological techniques are the limelight of the article. 相似文献
86.
Neural Computing and Applications - Of concern in this work is an investigation of the heat and mass transfer mechanisms in the presence of first-order chemical reaction for an incompressible flow... 相似文献
87.
Estimation of Clark’s Instantaneous Unit Hydrograph Parameters and Development of Direct Surface Runoff Hydrograph 总被引:1,自引:1,他引:1
Muhammad Masood Ahmad Abdul Razzaq Ghumman Sajjad Ahmad 《Water Resources Management》2009,23(12):2417-2435
We present a method to estimate Time of Concentration (T
c) and Storage Coefficient (R) to develop Clark’s Instantaneous Unit Hydrograph (CIUH). T
c is estimated from Time Area Diagram of the catchment and R is determined using optimization approach based on Downhill Simplex technique (code written in FORTRAN). Four different objective
functions are used in optimization to determine R. The sum of least squares objective function is used in a novel way by relating it to slope of a linear regression best fit
line drawn between observed and simulated peak discharge values to find R. Physical parameters (delineation, land slope, stream lengths and associated drainage areas) of the catchment are derived
from SPOT satellite imageries of the basin using ERDAS: Arc GIS is used for geographic data processing. Ten randomly selected
rainfall–runoff events are used for calibration and five for validation. Using CIUH, a Direct surface runoff hydrograph (DSRH)
is developed. Kaha catchment (5,598 km2), part of Indus river system, located in semi-arid region of Pakistan and dominated by hill torrent flows is used to demonstrate
the applicability of proposed approach. Model results during validation are very good with model efficiency of more than 95%
and root mean square error of less than 6%. Impact of variation in model parameters T
c and R on DSRH is investigated. It is identified that DSRH is more sensitive to R compared to T
c. Relatively equal values of R and T
c reveal that shape of DSRH for a large catchment depends on both runoff diffusion and translation flow effects. The runoff
diffusion effect is found to be dominant. 相似文献
88.
Tayyab Mahmood Ishtiaq Hussain Bokhari Masood Iqbal Tariq Mahmood Naseer Ahmed Muhammad Israr 《Progress in Nuclear Energy》2011,53(6):729-735
Neutronic and thermal hydraulic analyses have been carried out for current core of Pakistan Research Reactor-1 (PARR-1). Comparison was made between calculated and measured key neutronic parameters. Reactor core parameters important for reactor operation and safety have been calculated. Calculated neutronic parameters include: excess reactivity, shut down margin, control rod worth, peak power density location, criticality position, peaking factors, neutron flux in fuel elements and neutron flux at irradiation sites in the core. Calculated thermal hydraulic parameters include: steady-state temperatures and peak temperatures at fuel centerline, clad surface and in water coolant. In order to determine safety margins, heat fluxes at Onset of Nucleate Boiling (ONB), Onset of Flow Instability (OFI) and Departure from Nucleate Boiling (DNB) were determined using standard correlations. After assembling the core, performance of the core was also evaluated by experimentation. The core was assembled and some of the core parameters namely: excess reactivity, shut down margin, control rod worth and flux profile at in-core irradiation sites have been measured. On comparison with experimental data, reasonable agreement has been found between the calculated and the measured parameters. 相似文献
89.
Rashid Masood Khan Waseem Iqbal Muhammad Faisal Amjad Haider Abbas Hammad Afzal Abdul Rauf Maruf Pasha 《The Journal of supercomputing》2018,74(10):5060-5081
Recent years have seen tremendous increase in crime and terrorism all over the world which has necessitated continuous surveillance of public spaces, commercial entities and residential areas. CCTV cameras are an integral part of any modern surveillance system and have evolved significantly. They are a vital part of any investigation that follows a criminal or terrorism incident by providing invaluable evidence. In this paper, we show that the Advance Systems Format (ASF) file used in most IP cameras, which is also the main file containing metadata about the streaming packets, is vulnerable to forgery. This file is stored in plain text and any technically savvy person can forge it; therefore, a mechanism is needed to prevent it. To that end, we have gathered critical artifacts from an ASF file of IP cameras and carried out their forensic analysis. The analysis performed during this study demonstrates successful detection of forgery/tampering of evidence in IP cameras. 相似文献
90.
An analytical approach for the thermal behavior of two-dimensional rectangular flux channels with arbitrary boundary conditions on the source plane is presented. The boundary condition along the source plane can be a combination of the first kind boundary condition (Dirichlet or prescribed temperature) and the second kind boundary condition (Neumann or prescribed heat flux). To model the boundary conditions along the source plane, the method of least squares is used. The proposed solution is in the form of Fourier series expansion and can be applied to both symmetrical and non-symmetrical channels. This method is more general than other approaches and there is no need to use equivalent heat flux distributions to model isothermal heat sources. The general approach for obtaining the multidimensional temperature profile in flux channels and the advantages of the least-square method is discussed. The proposed solution can be used to calculate the temperature at any specified point in the flux channel. Two case studies are presented. The first case study is a flux channel with five discretely specified contact temperatures along the source plane. The second case study has both of the first kind and second kind boundary conditions on the source plane. The analytical results for both systems are compared with finite element method using a commercial software package. It is shown that the proposed approach can precisely model the temperature profile over the flux channel. 相似文献