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31.
This paper deals with the nonisothermal boundary layer flow of Cross fluid due to a stretching sheet. Unlike previous studies on boundary layer flow of Cross fluid, a nonsimilar formulation is adopted to transform the boundary layer equations into nondimensional form. The problem is characterized by three dimensionless parameters, namely, the Deborah number, the Prandtl number, and dimensionless distance along the sheet. The transformed equations are simulated by a numerical scheme with the help of MAPLE software. The velocity and temperature profiles inside the boundary layer are calculated and shown graphically. The skin friction coefficient and Nusselt number at various axial stations are also tabulated for several values of Deborah number and Prandtl number. 相似文献
32.
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
33.
Muhammad Imran Fazal-e- Habib Saima Majeed Abdul Tawab Waqar Rauf Moazur Rahman 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(8):1530-1542
A simple, reliable and sensitive liquid chromatography-tandem mass spectrometry-based confirmatory method was redeveloped and validated for the simultaneous determination of chloramphenicol, thiamphenicol, florfenicol and florfenicol amine in chicken muscles. The analytes were extracted from minced chicken muscle with acetonitrile and ammoniated water mixture. A second extraction with ethyl acetate was followed by evaporation and dissolution of the residue in ammoniated methanol before defatting with n-hexane. Finally, the extract was further cleaned up by dispersive solid phase extraction using C-18 end-capped dispersive material. The validation protocol was adapted from the European Commission Decision 2002/657/EC and all the performance characteristics were successfully satisfied. The recoveries of all the analytes were found to be in the range of 86.4–108.1% and the precision values, within day and between days, ranged from 2.7% to 11% and 4.4% to 16.3%, respectively. The method was tested in various incurred samples and applied to analyse a wide range of random poultry market samples (n = 120) collected from three cities of the Punjab, Pakistan. Chloramphenicol and florfenicol residues were detected at low levels in less than 11% of the samples. Chloramphenicol was detected only in 4 samples with the concentration range of 0.17–0.477 µg kg–1, whereas the levels of florfenicol/florfenicol amine residues detected in 9 samples ranged from 8.7 to 32.8 µg kg–1. Moreover, most of the florfenicol residues were identified as tissue bound, extractable only after strong acid hydrolysis. 相似文献
34.
Ahmed Bilal Awan Muhammad Zubair Guftaar Ahmed Sardar Sidhu Abdul Rauf Bhatti Ahmed G. Abo‐Khalil 《国际能源研究杂志》2019,43(12):6296-6321
The aim of this research is to analyze the techno‐economic performance of hybrid renewable energy system (HRES) using batteries, pumped hydro‐based, and hydrogen‐based storage units at Sharurah, Saudi Arabia. The simulations and optimization process are carried out for nine HRES scenarios to determine the optimum sizes of components for each scenario. The optimal sizing of components for each HRES scenario is determined based on the net present cost (NPC) optimization criterion. All of the nine optimized HRES scenarios are then evaluated based on NPC, levelized cost of energy, payback period, CO2 emissions, excess electricity, and renewable energy fraction. The simulation results show that the photovoltaic (PV)‐diesel‐battery scenario is economically the most viable system with the NPC of US$2.70 million and levelized cost of energy of US$0.178/kWh. Conversely, PV‐diesel‐fuel cell system is proved to be economically the least feasible system. Moreover, the wind‐diesel‐fuel cell is the most economical scenario in the hydrogen‐based storage category. PV‐wind‐diesel‐pumped hydro scenario has the highest renewable energy fraction of 89.8%. PV‐wind‐diesel‐pumped hydro scenario is the most environment‐friendly system, with an 89% reduction in CO2 emissions compared with the base‐case diesel only scenario. Overall, the systems with battery and pumped hydro storage options have shown better techno‐economic performance compared with the systems with hydrogen‐based storage. 相似文献
35.
36.
The important problem of data classification spans numerous real life applications. The classification problem has been tackled by using Genetic Programming in many successful ways. Most approaches focus on classification of only one type of data. However, most of the real-world data contain a mixture of categorical and continuous attributes. In this paper, we present an approach to classify mixed attribute data using Two Layered Genetic Programming (L2GP). The presented approach does not transform data into any other type and combines the properties of arithmetic expressions (using numerical data) and logical expressions (using categorical data). The outer layer contains logical functions and some nodes. These nodes contain the inner layer and are either logical or arithmetic expressions. Logical expressions give their Boolean output to the outer tree. The arithmetic expressions give a real value as their output. Positive real value is considered true and a negative value is considered false. These outputs of inner layers are used to evaluate the outer layer which determines the classification decision. The proposed classification technique has been applied on various heterogeneous data classification problems and found successful. 相似文献
37.
Abdul Rauf Sheik Malay Kumar Ghosh Kali Sanjay Tondepu Subbaiah Barada Kanta Mishra Abdullahi Aalafara Baba 《Korean Journal of Chemical Engineering》2013,30(2):400-404
Nickel was recovered from a fertilizer industry spent catalyst by leaching with nitric acid followed by nickel hydroxide precipitation. The optimization of temperature, initial acid concentration and particle size for leaching of the spent catalyst was done through 23 factorial design. A maximum extraction of 91.9% was achieved at 90 °C, 1.5M HNO3 and 62.5 μm particle size. Temperature and acid concentration showed positive effect, while particle size showed no effect. A regression equation was developed and employed to predict conditions for 100% extraction which were experimentally tested. Nickel hydroxide was electrochemically precipitated from the leach liquor and its maximum discharge capacity was found to be 155 mAh/g. A 3-stage counter current leaching circuit was designed to obtain a leach liquor of suitable pH. XRD characterization of the precipitated Ni(OH)2 shows to consist of both α- and β-forms. 相似文献
38.
Prevalence of anemia among pregnant women and adolescent girls in 16 districts of India 总被引:2,自引:0,他引:2
Toteja GS Singh P Dhillon BS Saxena BN Ahmed FU Singh RP Prakash B Vijayaraghavan K Singh Y Rauf A Sarma UC Gandhi S Behl L Mukherjee K Swami SS Meru V Chandra P Chandrawati Mohan U 《Food and nutrition bulletin》2006,27(4):311-315
BACKGROUND: Nutritional anemia is one of India's major public health problems. The prevalence of anemia ranges from 33% to 89% among pregnant women and is more than 60% among adolescent girls. Under the anemia prevention and control program of the Government of India, iron and folic acid tablets are distributed to pregnant women, but no such program exists for adolescent girls. OBJECTIVE: To assess the status of anemia among pregnant women and adolescent girls from 16 districts of 11 states of India. METHODS: A two-stage random sampling method was used to select 30 clusters on the basis of probability proportional to size. Anemia was diagnosed by estimating the hemoglobin concentration in the blood with the use of the indirect cyanmethemoglobin method. RESULTS: The survey data showed that 84.9% of pregnant women (n = 6,923) were anemic (hemoglobin < 110 g/L); 13.1% had severe anemia (hemoglobin < 70 g/L), and 60.1% had moderate anemia (hemoglobin > or = 70 to 100 g/L). Among adolescent girls (n = 4,337)from 16 districts, the overall prevalence of anemia (defined as hemoglobin < 120 g/L) was 90.1%, with 7.1% having severe anemia (hemoglobin < 70 g/L). CONCLUSIONS: Any intervention strategy for this population must address not only the problem of iron deficiency, but also deficiencies of other micronutrients, such as B12 and folic acid and other possible causal factors. 相似文献
39.
Railway Engineering Science - The ballast layer, filled with fine particles like blown sand, is one of the important problems of ballasted railway tracks in desert areas. Blown sand, as a... 相似文献
40.
In this work, it is investigated whether electrochemical frequency modulation can be used to monitor crevice corrosion. With this novel technique, a potential signal consisting of two sine waves of different frequencies is applied to a corroding system. As a corroding system is non-linear in nature, the ac-response will contain non-linear components at harmonic and intermodulation frequencies. Analysis of these components can give information about the corrosion behavior of the system under investigation like the uniform corrosion rate. Crevice corrosion has been investigated by measuring the so-called “causality factors”, which are calculated from the ratio of the current components in the ac-response.According to ASTM standard G48, crevice corrosion has been investigated under the rubber band and cylindrical TFE-fluorocarbon block. Tests were also conducted by creating crevice between circular boundary of metallic sample and epoxy in which metal is engraved. Thus, three patterns of crevice corrosion have been used to see the response of causality factors for AISI 304. Besides some simulations with a simple mathematical model, experiments with artificial crevices were carried out in chloride containing water. The results show that in most cases these causality factors do change when the system goes from uniform corrosion to crevice corrosion. 相似文献