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      • KCI등재

        AVO-derived attributes to differentiate reservoir facies from non-reservoirs facies and fluid discrimination in Penobscot area, Nova Scotia

        Perveiz Khalid,Nisar Ahmed,Khalid Amin Khan,Mustansar Naeem 한국지질과학협의회 2015 Geosciences Journal Vol.19 No.3

        The discrimination of hydrocarbon (gas or oil) facies from non-hydrocarbon (wet sands) facies is an important goal in quantitative seismic interpretation and reservoir estimation. The differentiation of hydrocarbon facies from non-hydrocarbon in Mississauga Formation of early Cretaceous in Penobscot area is a difficult task due to smaller net pay thickness and shaly sand intervals. Based on seismic interpretation and wireline logs, five sand plays are identified in the middle of Mississauga Formation. Four sands have hydrocarbons while top of sand 5 represents hydrocarbon water transition zone. Among these four, the pay sand 4 is analyzed for hydrocarbon facies. Wireline logs and seismic data are used to derive various amplitude versus offset (AVO) based attributes such as: acoustic (IP) and shear (IS) impedances, Poisson ratio (σ) etc. Further, the combined attributes e.g., product of Lamé parameters (μ, λ) with density (ρ), their ratio (λ/μ), difference between bulk modulus (K) and shear modulus (μ), Δμρ/μρ, Δ(λ/μ + 2)(λ/μ + 2) and the pore space modulus (ΚP) are also analyzed to find out the best attribute as a hydrocarbon facies discriminator from non-hydrocarbon facies in the shale imbedded pay sand 4 of Mississauga Formation. First, petrophysical parameters such as P and S wave impedances, Lamé’s parameters etc. are extracted from log data. Then, appropriate pairs of seismic attributes are crossplotted so that the hydrocarbon and non-hydrocarbon facies cluster together for quick identification and interpretation. Gamma ray index is crossplotted against spontaneous potential log to mark sand and shale facies. Fluid substitution modeling for various fluid types and saturation is also done which demonstrate that the cross-plots between different rock physics parameters can be used to distinguish between reservoir fluids. Our analysis reveals single P-wave based attributes are not sufficient to discriminate fluids thus the use of multi-attributes such as KP, λρ and Κ-μ is more effective to discriminate the hydrocarbon and non-hydrocarbon facies. The analysis of these cross-plots was done to map the reservoir sands and the hydrocarbon-water contact.

      • KCI등재

        Unified Fault-Tolerant Control for Air-Fuel Ratio Control of Internal Combustion Engines with Advanced Analytical and Hardware Redundancies

        Amin Arslan Ahmed,Mahmood-ul-Hasan Khalid 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.3

        This paper proposes a Unifi ed Fault-Tolerant Control System (UFTCS) based on advanced analytical and hardware redundancies for Air-Fuel Ratio (AFR) control of Spark Ignition (SI) Internal Combustion (IC) engines. The advanced analytical redundancy part is termed the Hybrid Fault-Tolerant Control System (HFTCS) which consists of both active and passive types. The Lookup Tables (LTs) have been utilized in the active part and a robust proportional feedback controller of high gain with fuel throttle actuator has been implemented in the passive part. Since the failure of any two sensors at the same time or failure of a single actuator causes engine shutdown, an advanced hardware redundancy protocol Modifi ed Triple Modular Redundancy (MTMR) has been suggested for the sensors, and Dual Redundancy (DR) has been proposed for the actuators to prevent the tripping of the engine. MATLAB/Simulink simulation results indicate that the suggested UFTCS is highly robust to the sensor faults in both normal and noisy conditions. The probabilistic reliability analysis for various hardware redundancy schemes also proves the greater overall reliability of UFTCS. Finally, a comparison with the existing AFR control systems is carried out to demonstrate its superior performance

      • Enhancement of thermoelectric properties of MBE grown un-doped ZnO by thermal annealing

        Khalid, Mahmood,Asghar, Muhammad,Ali, Adnan,Ajaz-Un-Nabi, M.,Arshad, M. Imran,Amin, Nasir,Hasan, M.A. Techno-Press 2015 Advances in energy research Vol.3 No.2

        In this paper, we have reported an enhancement in thermoelectric properties of un-doped zinc oxide (ZnO) grown by molecular beam epitaxy (MBE) on silicon (001) substrate by annealing treatment. The grown ZnO thin films were annealed in oxygen environment at $500^{\circ}C-800^{\circ}C$, keeping a step of $100^{\circ}C$ for one hour. Room temperature Seekbeck measurements showed that Seebeck coefficient and power factor increased from 222 to $510{\mu}V/K$ and $8.8{\times}10^{-6}$ to $2.6{\times}10^{-4}Wm^{-1}K^{-2}$ as annealing temperature increased from 500 to $800^{\circ}C$ respectively. This observation was related with the improvement of crystal structure of grown films with annealing temperature. X-ray diffraction (XRD) results demonstrated that full width half maximum (FWHM) of ZnO (002) plane decreased and crystalline size increased as the annealing temperature increased. Photoluminescence study revealed that the intensity of band edge emission increased and defect emission decreased as annealing temperature increased because the density of oxygen vacancy related donor defects decreased with annealing temperature. This argument was further justified by the Hall measurements which showed a decreasing trend of carrier concentration with annealing temperature.

      • Efficient Hierarchical Clustering Routing in Wireless Sensor Networks

        Rais Amine,Bouragba Khalid,Ouzzif Mohammed 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.9

        The routing protocol allows routing data from source to destination through intermediate nodes up to the sink. In the hierarchical routing based on the clustering, every cluster head node forms its cluster with their neighbor nodes. The cluster heads are responsible of their clusters. In fact, they coordinate between nodes in the cluster for intra-cluster communication and route data to the other clusters for inter-cluster communication. In this article we propose a centralized and periodic protocol named Efficient Clustering Routing Protocol (ECRP). Our protocol is based on a modified version of CLARANS algorithm; it takes into account the location and the remaining energy of the sensor nodes to divide the sensed area to disjoint and balanced clusters. The simulation results show that the proposed protocol is more efficient than the existing hierarchical protocols in terms of packet delivery ratio, and energy consumption.

      • Data Science and Machine Learning Approach to Improve E-Commerce Sales Performance on Social Web

        Hussain Saleem,Khalid Bin Muhammad,Altaf H. Nizamani,Samina Saleem,M. Khawaja Shaiq Uddin,Syed Habib-ur-Rehman,Amin Lalani,Ali Muhammad Aslam International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.8

        E-Commerce is a buzzword well known for electronic commerce activities including but not limited to the online shopping, digital payment transactions, and B2B online trading. In today's digital age, e-commerce has been playing a very important and vital role in areas such as retail shopping, sales automation, supply chain management, marketing and advertisement, and payment services. With a huge amount of data been collected from various e-commerce services available, there are multiple opportunities to use that data to analyze graphs and trends. Strategize profitable activities, and forecast future trade. This paper explains a contemporary approach for collecting key data metrics and implementing cost-effective automation that will support in improving conversion rates and sales performance of the e-commerce websites resulting in increased profitability.

      • KCI등재

        Improved Current Controlled Doubly Fed Induction Generator Model with Grid Integration Under Sub and Super Synchronous Conditions

        Arslan Ahmed Amin,Hamza Ahmad,Hassan Khalid,Neha Masroor,Huda Mahmood,Muhammad Abubakar 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.1

        This paper presents the development and experimental verifi cation of the mathematical model of wind turbine and Doubly Fed Induction Generator (DFIG) using the current control and voltage estimation method between the DC link. The rotor of the induction generator (IG) is rotated with the wind turbine at a specifi c speed. The DFIG is directly coupled with a grid station and the synchronization between DFIG and the grid station is controlled by setting two converters: Machine Side Converter (MSC) implemented with the rotor side and Grid Side Converter (GSC) implemented with the grid. PI controllers have been utilized in the control loops and the parametric range is extracted to maximize the mechanical power transferred to the IG rotor. The model is tested under three conditions DFIG running at super synchronous speed, synchronous speed, and under synchronous speed using MATLAB Simulink. In the end, the same model is also tested through a series of experiments using lab modules. The results show that the proposed model is much simplifi ed and accurate as compared to previous versions available in the literature.

      • KCI등재

        Increased ERCP volume improves cholangiogram interpretation: a new performance measure for ERCP training?

        Shyam Vedantam,Sunil Amin,Ben Maher,Saqib Ahmad,Shanil Kadir,Saad Khalid Niaz,Mark Wright,Nadeem Tehami 대한소화기내시경학회 2022 Clinical Endoscopy Vol.55 No.3

        Background/Aims: Cholangiogram interpretation is not used as a key performance indicator (KPI) of endoscopic retrograde cholangiopancreatography(ERCP) training, and national societies recommend different minimum numbers per annum to maintain competence. This study aimed to determine the relationship between correct ERCP cholangiogram interpretation and experience. Methods: One hundred fifty ERCPists were surveyed to appropriately interpret ERCP cholangiographic findings. There were threegroups of 50 participants each: “Trainees,” “Consultants group 1” (performed >75 ERCPs per year), and “Consultants group 2” (performed>100 ERCPs per year). Results: Trainees was inferior to Consultants groups 1 and 2 in identifying all findings except choledocholithiasis outside the intrahepaticduct on the initial or completion/occlusion cholangiogram. Consultants group 1 was inferior to Consultants group 2 in identifyingStrasberg type A bile leaks (odds ratio [OR], 0.86; 95% confidence interval [CI], 0.77−0.96), Strasberg type B (OR, 0.84; 95% CI,0.74−0.95), and Bismuth type 2 hilar strictures (OR, 0.81; 95% CI, 0.69−0.95). Conclusions: This investigation supports the notion that cholangiogram interpretation improves with increased annual ERCP casevolumes. Thus, a higher annual volume of procedures performed may improve the ability to correctly interpret particularly difficultfindings. Cholangiogram interpretation, in addition to bile duct cannulation, could be considered as another KPI of ERCP training.

      • KCI등재

        Diversity in Betasatellites Associated with Cotton Leaf Curl Disease During Source-To-Sink Movement Through a Resistant Host

        Iftikhar Ali Khan,Khalid Pervaiz Akhtar,Fazal Akbar,Ishtiaq Hassan,Imran Amin,Muhammad Saeed,Shahid Mansoor 한국식물병리학회 2016 Plant Pathology Journal Vol.32 No.1

        Cotton leaf curl is devastating disease of cotton characterized by leaf curling, vein darkening and enations. The disease symptoms are induced by DNA satellite known as Cotton leaf curl Multan betasatellite (CLCuMuB), dominant betasatellite in cotton but another betasatellite known as Chili leaf curl betasatellite (ChLCB) is also found associated with the disease. Grafting experiment was performed to determine if host plant resistance is determinant of dominant population of betasatellite in cotton (several distinct strains of CLCuMuB are associated with the disease). Infected scion of Gossypium hirsutum collected from field (the source) was grafted on G. arboreum, a diploid cotton species, resistant to the disease. A healthy scion of G. hirsutum (sink) was grafted at the top of G. arboreum to determine the movement of virus/betasatellite to upper susceptible scion of G. hirsutum. Symptoms of disease appeared in the upper scion and presence of virus/betasatellite in the upper scion was confirmed via molecular techniques, showing that virus/betasatellite was able to move to upper scion through resistant G. arboreum. However, no symptoms appeared on G. arboreum. Betasatelites were cloned and sequenced from lower scion, upper scion and G. arboreum which show that the lower scion contained both CLCuMuB and ChLCB, however only ChLCB was found in G. arboreum. The upper scion contained CLCuMuB with a deletion of 78 nucleotides (nt) in the non-coding region between Arich sequence and βC1 gene and insertion of 27 nt in the middle of βC1 ORF. This study may help in investigating molecular basis of resistance in G. arboreum.

      • Nonlocal strain gradient theory for buckling and bending of FG-GRNC laminated sandwich plates

        Muhammad Basha,Ahmed Amine Daikh,Ammar Melaibari,Ahmed Wagih,Ramzi Othman,Khalid H. Almitani,Mostafa A. Hamed,Alaa Abdelrahman,Mohamed A Eltaher 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.43 No.5

        The bending and buckling behaviours of FG-GRNC laminated sandwich plates are investigated by using novel fivevariables quasi 3D higher order shear deformation plate theory by considering the modified continuum nonlocal strain gradient theory. To calculate the effective Young’s modulus of the GRNC sandwich plate along the thickness direction, and Poisson’s ratio and mass density, the modified Halpin-Tsai model and the rule of the mixture are employed. Based on a new field of displacement, governing equilibrium equations of the GRNC sandwich plate are solved using a developed approach of Galerkin method. A detailed parametric analysis is carried out to highlight the influences of length scale and material scale parameters, GPLs distribution pattern, the weight fraction of GPLs, geometry and size of GPLs, the geometry of the sandwich plate and the total number of layers on the stresses, deformation and critical buckling loads. Some details are studied exclusively for the first time, such as stresses and the nonlocality effect.

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