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1.
Modeling for Various Design Options of a Canal System 总被引:1,自引:1,他引:0
Irrigated agriculture is backbone of economy in many countries worldwide, including Pakistan with its large irrigation system.
Systemic Enhancements are periodically implemented to improve the performance of the system. In this paper the performance
of canals has been investigated for various operations. Data regarding discharge of outlets and the canals was collected by
field measurements. Crop-water requirements, bed slope of canals, cross-sectional details, longitudinal profile and outlet
details, were obtained from the Irrigation Department. It was noticed that the performance of canals is not satisfactory under
prevailing conditions. Different operational strategies for change of unlined to lined conditions, different discharge conditions
and outlet dimensions were evaluated using CanalMan model. It was established through extensive research that the performance
of the canals can be improved by lining and changing outlet dimensions. Modified dimensions of outlets for better performance
were estimated by iterative method of optimization. 相似文献
2.
Ishtiaq Hassan Abdul Razzaq Ghumman Hashim Nisar Hashmi Abdul Sattar Shakir 《Civil Engineering and Environmental Systems》2013,30(4):365-376
This study has been carried out to forecast the impact of global warming on the precipitation pattern of Saudi Arabia by the end of year 2100. Simulation has been done using EdGCM model software (with available 8×10 resolution) developed at Columbia University on which there have been produced global precipitation maps for the seasonal and annual averages for the last 5 years (2096–2100). For each map, EdGCM grid values surrounding Saudi Arabia are used as input to one of the tools of Eagle point software called surface modelling (SM). SM is a new approach for downscaling global climate model results. SM software modelled out isohyets at 0.2 mm/day interval. The results indicate that the present pattern of precipitation (more in winter and less in summer) is going to change by almost equal occurrence of precipitation in all seasons for double_CO2 (2CO2) experiment. The 2CO2 experiment indicates an increase of about 16.05% over the annual average precipitation across the country. 相似文献
3.
Sobia Noreen Sara Hasan Shazia Akram Ghumman Syed Nasir Abbas Bukhari Bushra Ijaz Huma Hameed Huma Iqbal Afeefa Aslam Mervat Abdelaziz Mohamed Elsherif Shazia Noureen Hasan Ejaz 《International journal of molecular sciences》2022,23(5)
The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target. 相似文献
4.
Muhammad Masood Ahmad Abdul Razzaq Ghumman Sajjad Ahmad Hashim Nisar Hashmi 《Water Resources Management》2010,24(12):2971-2989
Water resources planning and management requires hydrologic models to estimate runoff from a catchment. For catchments with
limited data, the choice of model and identification of its parameters is very important for development of a direct runoff
hydrograph. A method is presented to determine a unique pair of hydrologic parameters of the Nash Model, number of linear
cascade (n) and storage coefficient (k), using optimization based on Downhill Simplex technique. In this study physical parameters
of the catchment are derived from (SPOT) satellite imageries of the basin using ERDAS software. Four different objective functions
of varying complexity are tested to find the best solution. Weighted root mean square error (RMSE) and Model Efficiency (Nash-Sutcliffe
coefficient) are used to evaluate the model performance. Using the NASH model, a direct surface runoff hydrograph (DSRH) is
developed. Kaha catchment is part of Indus river system and is located in the semi-arid region of Pakistan. This catchment
is dominated by hill torrent flows and is used in this work to demonstrate the applicability of the proposed method. Ten randomly
selected rainfall-runoff events are used for calibration and five events are used for validation. Model results during validation
are very promising with model efficiency exceeding 93% and error in peak discharge under 8%. The sensitivity of the Nash model
output in response to variation in hydrologic parameters n and k is also investigated. When evaluating the hydrologic response
of large catchments, model output is more sensitive to n as compared to k indicating that the runoff diffusion phenomenon
is dominant compared to translation flow effects. 相似文献
5.
M. A. Khattak Anique Mukhtar Imran S. S. Ghumman Miraj Muhammad Jan 《Journal of Failure Analysis and Prevention》2018,18(2):274-279
Pressure cooker is a closed domestic pressure cooking vessel for use with external heat source and capable of maintaining nominal cooking pressure up to 1.0 kgf/cm2 (100 kN/m2 approximately) gauge nominal. In pressure cookers, despite the development of electronic controllers, the basic edition of such vessels are still equipped with fewer advanced safety functions due to economic constraints. Although the provision of pressure relief valves (PRV) is considered as one of the major protective features, however, pressure cooker failure accidents have been reported frequently. This paper describes the analysis of pressure cooker failure that failed prematurely after 1 year of service considering the design life of > 5 years. It was hypothesized that the root cause of pipe failure was either material degradation from exposure to an aggressive environment or an inherent defect in the pressure cooker. To test this hypothesis, a thorough visual examination of the exhumed failed section and the fracture surface was undertaken, followed by liquid penetrant testing, material identification, hardness testing, and metallographic analysis. Computational models of static and transient loading were also used to determine the stress distribution along the actual geometry of the failed cooker and to understand the main causes of recurrent failures. Visual and macroscale examination revealed significant body deformation at the lower dish-ended shell showing distorted locking grooves. It was also noticed that dirt and food particle, from the earlier cooking, were stuck in the pressure valves orifice. In addition, no evidence of metallurgical defect was observed. The inspection indicated that the cause of failure is primarily due to the choking of pressure relief value (PRV) and overpressure safety valves. Consequently, the pressure release occurred from the sealing side of the top lid, which resulted in its ejection. 相似文献
6.
M.A. Neto E.L. SilvaC.A. Ghumman O.M. TeodoroA.J.S. Fernandes F.J. OliveiraR.F. Silva 《Thin solid films》2012,520(16):5260-5266
Sintered silicon nitride (Si3N4) ceramic substrates were investigated as dielectric substrates for the growth of metal-like boron-doped nanocrystalline diamond (NCD) and microcrystalline diamond coatings via the Hot Filament Chemical Vapor Deposition (HFCVD) technique. The structural, electrical and chemical properties of both the ceramic substrates and the diamond coatings may potentiate their applicability in particular in harsh environments and highly demanding situations. Boron doping was achieved via a boron oxide solution in ethanol dragged into the reaction chamber with argon. The coatings were characterized by scanning electron microscopy, UV μ-Raman scattering, X-ray diffraction, time-of-flight secondary ion mass spectroscopy, Brale indentation for adhesion evaluation and two-point contact probe for resistivity measurements. The HFCVD technique led to a maximal growth rate of about 1 μm/h. Several metal-like boron doped diamond coatings were obtained. It was found that at lower substrate temperature, lower system pressure and higher methane concentration, the resistivity of the conducting NCD coatings is about 3 orders of magnitude higher when compared with samples obtained with higher substrate temperature, higher system pressure and lower methane concentration. Nevertheless, for every metal-like boron-doped coating the use of the Si3N4 ceramic substrate guaranteed a superior adhesion level. 相似文献
7.
Atinder Ghumman Narpinder Singh Amritpal Kaur 《International Journal of Food Science & Technology》2020,55(4):1744-1753
Effect of sprouting on the content of different phenolic compounds and starch characteristics of horse gram was compared to that of lentil. Increase in gallic acid, p-coumaric acid and ferulic chlorogenic acid content was observed in horse gram and lentil, respectively, with sprouting. Luteolin content in basic-bound fraction increased in lentil and decreased in horse gram with sprouting. Lentil starches showed higher retrogradation tendency than horse gram starches. Storage modulus and retrogradation tendency of starch gels decreased initially followed by an increase after 96 h of sprouting. Horse gram starches showed higher crystallinity than lentil starches, and crystallinity increased with increase in sprouting period. Horse gram starches showed higher onset, peak and conclusion temperature than lentil starches. Transition temperatures decreased with increase in sprouting duration in both the pulses. Sprouting changed the crystalline structure of starch significantly as well as phenolic composition of both the pulses. 相似文献
8.
Estimation of Clark’s Instantaneous Unit Hydrograph Parameters and Development of Direct Surface Runoff Hydrograph 总被引:2,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
9.
Zain Shabbir Anas Razzaq Ghumman Shabbir Majeed Chaudhry 《Circuits, Systems, and Signal Processing》2016,35(9):3113-3134
A low-power, high-speed \(4\times 4\) multiplier using Dadda algorithm is proposed. The full adder blocks used in this multiplier have been designed using reduced-split precharge-data driven dynamic sum logic. Flip flops used in the pipeline registers have been designed to increase input signal noise margin, resulting in the minimization of output signal glitches. The multiplier circuit is implemented in 1P-9M Low-K UMC 90nm CMOS process technology. Post-layout simulations are carried out using Cadence Virtuoso. The proposed multiplier operates at a clock frequency of 3.5 GHz, with an average dynamic power consumption of 1.096 mW at a temperature of \(27\,^{\circ }\hbox {C}\) and 1 V supply voltage and occupies a chip area of \(76\,\upmu \hbox {m}\times 102\,\upmu \hbox {m}\). 相似文献
10.
Atinder Ghumman Narpinder Singh Amritpal Kaur 《International Journal of Food Science & Technology》2017,52(10):2191-2200
Chemical, nutritional and antiradical properties of juice and shoot powder from wheatgrass and pulses were evaluated. Wheatgrass powder (WP) showed higher radical scavenging capacity, ash and chlorophyll content and lower protein content as compared to pulse powder (PP). Wheatgrass (WJP) juice powder had significantly higher K and Mg content as compared to pulse juice powder (PJP). Powders with relatively higher K and Mg content had higher radical scavenging capacity and chlorophyll content. Vanillic acid was present only in free form in both WP and PP. Luteolin was equally distributed in acid‐ and base‐bound form; sinapic acid was higher in base‐bound fraction; and protocatechuic acid was higher in acid‐bound form in both the sources. Positive correlations were found between radical scavenging capacity and ferulic acid and sinapic acid, whereas radical scavenging capacity was negatively correlated with gallic acid and p‐coumaric acid. WJP had higher glutamic acid, histidine, threonine, citrulline, arginine, gamma‐amino butyric acid (GABA) and leucine as compared to PJP. The present study highlights the nutritional benefits of wheatgrass juice. 相似文献