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Search Results: 1 - 10 of 429 matches for " Taimoor Abid "
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Entrepreneur as an authentic leader: A study of small and medium sized enterprises in Pakistan
Taimoor Abid,Mohsin Altaf,Usman Yousaf,Mohammad Majid Mehmood Bagram
Management Science Letters , 2012,
Abstract: The aim of this paper is to explore the authentic leadership styles of an entrepreneurs and its impact on employee’s commitment and satisfaction. By using the authentic leadership model, this study seeks to give a tentative test of the connection among employees’ awareness of the business creator as an authentic leader and the employees’ attitudes. Findings are that the opinion of employees’ about authentic leadership serves as the intoxicating analyst of employee job satisfaction and organizational commitment.
Entrepreneur as Anauthentic Leader's in Small and Medium Sized Enterprises in Pakistan
Taimoor Abid,MohsinAltaf,UsmanYousaf,Mohammad Majid Mehmood Bagram
School of Doctoral Studies Journal , 2012,
Abstract: The aim of this paper is to explore the Authentic leadership styles of an entrepreneurs and its impact on Employee's Commitment and satisfaction. By Using the Authentic Leadership Model, this study seeks to give a tentative test of the connection among employees' awareness of the business creator as an authentic leader and the employees' attitudes. Findings are that the opinion of employees' about authentic leadership serves as the intoxicating analyst of employee job satisfaction and organizational commitment.
Hardware Neural Networks Modeling for Computing Different Performance Parameters of Rectangular, Circular, and Triangular Microstrip Antennas
Taimoor Khan,Asok De
Chinese Journal of Engineering , 2014, DOI: 10.1155/2014/924927
Abstract: In the last one decade, neural networks-based modeling has been used for computing different performance parameters of microstrip antennas because of learning and generalization features. Most of the created neural models are based on software simulation. As the neural networks show massive parallelism inherently, a parallel hardware needs to be created for creating faster computing machine by taking the advantages of the parallelism of the neural networks. This paper demonstrates a generalized neural networks model created on field programmable gate array- (FPGA-) based reconfigurable hardware platform for computing different performance parameters of microstrip antennas. Thus, the proposed approach provides a platform for developing low-cost neural network-based FPGA simulators for microwave applications. Also, the results obtained by this approach are in very good agreement with the measured results available in the literature. 1. Introduction Low profile, conformable to planar and nonplanar surfaces, most economical, mechanically robust, light weight, and easily mount-ability are the key advantages of microstrip antennas (MSAs). Because of these add-on advantages, the microstrip antennas are widely used in many communication applications. Since the microstrip antenna operates only in the vicinity of the resonant frequency, it needs to be calculated accurately for analyzing the microstrip antennas. Similarly, for designing the microstrip antennas, the physical dimension(s) must also be calculated precisely [1]. There are two conventional ways for analyzing and/or designing the microstrip antennas, analytical methods and numerical methods. The analytical methods provide a good spontaneous explanation for the operation of microstrip antennas. As the analytical methods are based on the physical assumptions for simplifying the radiation mechanism of the microstrip antennas, these methods are not suitable for many structures, where the thickness of the substrate is not very thin. The numerical methods also provide the accurate results but the analysis using these methods leads to the expressions as an integral equation. The choice of test functions and path integrations appears to be more critical without any initial assumption in the final stage of the numerical results. Also, these methods require a new solution for any sort of alteration in the geometry. The problems associated with these conventional methods can be overcome by selecting the appropriate neural network methods [1]. In recent years, artificial neural networks (ANNs) have acquired
A Generalized ANN Model for Analyzing and Synthesizing Rectangular, Circular, and Triangular Microstrip Antennas
Taimoor Khan,Asok De
Chinese Journal of Engineering , 2013, DOI: 10.1155/2013/647191
Abstract: Since last one decade, artificial neural network (ANN) models have been used as fast computational technique for different performance parameters of microstrip antennas. Recently, the concept of creating a generalized neural approach for different performance parameters has been motivated in microstrip antennas. This paper illustrates a generalized neural approach for analyzing and synthesizing the rectangular, circular, and triangular MSAs, simultaneously. Such approach is very much required for the antenna designers for getting instant answer for the required parameters. Here, total seven performance parameters of three different MSAs are computed using generalized neural approach as such a method is rarely available in the open literature even for computing more than three performance parameters, simultaneously. The results thus obtained are in very good agreement with the measured results available in the referenced literature for all seven cases. 1. Introduction Microstrip antennas are being widely used for different applications in wireless communication due to several attractive features: low profile, conformable to planar, and nonplanar surfaces, most economical, mechanically robust, light weight, easy mount-ability, and so forth. [1]. Since the microstrip antenna (MSA) operates only in the vicinity of resonance frequency, it needs to be calculated accurately for analyzing the microstrip antennas. Similarly, for designing the MSAs, the physical dimensions must also be calculated precisely. Several classical methods [2–14] have been used for computing the resonance frequency of rectangular MSAs [2–5], resonance frequency of circular MSAs [6–12], and resonance frequency of triangular MSAs [13, 14]. These methods can broadly be categorized as analytical methods and numerical methods. The analytical methods provide a good spontaneous explanation for the operation of MSAs. These methods are based on the physical assumptions for simplifying the radiation mechanism of the MSAs and are not suitable for many structures where the thickness of the substrate is not very thin. On the other hand, the numerical methods provide accurate results but only at the cost of huge mathematical burden in the form of complex integral equations. The choice of test function and path integration appears to be more critical without initial assumptions in the final stage of the numerical results. Also, these methods require a new solution even for a minor alteration in the geometry. Thus, the requirement for having a new solution for every minor change in the geometry as well
Line-of-Sight Obstruction Analysis for Vehicle-to-Vehicle Network Simulations in a Two-Lane Highway Scenario
Taimoor Abbas,Fredrik Tufvesson
International Journal of Antennas and Propagation , 2013, DOI: 10.1155/2013/459323
Abstract: In vehicular ad-hoc networks (VANETs) the impact of vehicles as obstacles has largely been neglected in the past. Recent studies have reported that the vehicles that obstruct the line-of-sight (LOS) path may introduce 10–20?dB additional loss, and as a result reduce the communication range. Most of the traffic mobility models (TMMs) today do not treat other vehicles as obstacles and thus cannot model the impact of LOS obstruction in VANET simulations. In this paper the LOS obstruction caused by other vehicles is studied in a highway scenario. First a car-following model is used to characterize the motion of the vehicles driving in the same direction on a two-lane highway. Vehicles are allowed to change lanes when necessary. The position of each vehicle is updated by using the car-following rules together with the lane-changing rules for the forward motion. Based on the simulated traffic a simple TMM is proposed for VANET simulations, which is capable to identify the vehicles that are in the shadow region of other vehicles. The presented traffic mobility model together with the shadow fading path-loss model can take into account the impact of LOS obstruction on the total received power in the multiple-lane highway scenarios. 1. Introduction Vehicle-to-vehicle (V2V) communication is an emerging technology that has been recognized as a key communication paradigm for safety and infotainment applications in future intelligent transportation systems (ITS). In recent years extensive research efforts have been made to design reliable and fault tolerant vehicular ad-hoc network (VANET) communication protocols. However, the propagation channel is one of the key performance limiting factor which is not yet completely understood [1]; several aspects such as the impact of antenna placement on vehicles [2] and line-of-sight obstruction by other vehicles on V2V communication have largely been neglected in the past. In [3, 4], it is stated that a vehicle that obstructs the LOS path between the transmitter (TX) and receiver (RX) vehicle may introduce 10?dB additional loss in the received power and as a result cause 3 times reduced communication range. This additional power loss can increase up to 20?dB if the obstructing vehicle is tall and close to the RX vehicle [5]. Several network simulators suitable for VANET simulations exist today, for example, ns-2 [6], OMNet++ [7], ns-3 [8], and JiST/SWANS [9]. These simulators are different from each other in terms of run-time performance and memory usage [10]. Most of these simulators do not consider the impact of neighboring
Estimation of Different Performance Parameters of Slotted Microstrip Antennas with Air-Gap Using Neural Networks
Taimoor Khan,Asok De
ISRN Electronics , 2014, DOI: 10.1155/2014/296105
Abstract: Over the past decade, artificial neural networks have emerged as fast computational medium for predicting different performance parameters of microstrip antennas due to their learning and generalization features. This paper illustrates a neural network model for instantly predicting the resonance frequencies, gains, directivities, antenna efficiencies, and radiation efficiencies for dual-frequency operation of slotted microstrip antennas with air-gap. The proposed neural model is valid for any arbitrary slot-dimensions and inserted air-gap within their specified ranges. A prototype is fabricated using Roger’s substrate and its performance is measured for validation. A very good agreement is achieved in simulated, predicted, and measured results. 1. Introduction There are many situations of wireless communication where dual-frequency operation is required such as satellite communication, radar systems, and global positioning system (GPS). Microstrip antennas (MSAs), because of operating in dual-frequency mode, have eliminated two single-frequency operated antennas in these applications [1]. Different researchers have proposed different techniques for obtaining dual resonance such as multilayered stacked patch [2, 3], slotted rectangular patch [4], square patch with notches [5], patch loaded with shorting posts [6] or varactor diodes [7], and rectangular patch fed by an inclined slot [8]. These methods [2–8] can roughly be categorized as analytical methods and numerical methods. The analytical methods provide a good spontaneous explanation for the operation of MSAs. These techniques are based on the physical assumptions for simplifying the radiation mechanism of the MSAs but are not suitable for many microstrip structures where the thickness of the substrate is not very thin. On the other hand, the numerical methods provide accurate results but only at the cost of using complex mathematical expressions in the form of integral equations. The choice of test functions and path integrations appear to be more critical without initial assumptions in the final stage of the numerical results. Also, these approaches require a new solution even for an infinitesimal alteration in the geometry. Thus, the requirement for having a new solution for every small alteration in the geometry as well as the problems associated with the thickness of the substrates in analytical methods leads to complexities and processing cost [9]. Recently, artificial neural networks (ANNs) models have acquired tremendous applications in the wireless communication due to their ability and
Line-of-Sight Obstruction Analysis for Vehicle-to-Vehicle Network Simulations in a Two-Lane Highway Scenario
Taimoor Abbas,Fredrik Tufvesson
Computer Science , 2013,
Abstract: In vehicular ad-hoc networks (VANETs) the impact of vehicles as obstacles has largely been neglected in the past. Recent studies have reported that the vehicles that obstruct the line-of-sight (LOS) path may introduce 10-20 dB additional loss, and as a result reduce the communication range. Most of the traffic mobility models (TMMs) today do not treat other vehicles as obstacles and thus can not model the impact of LOS obstruction in VANET simulations. In this paper the LOS obstruction caused by other vehicles is studied in a highway scenario. First a car-following model is used to characterize the motion of the vehicles driving in the same direction on a two-lane highway. Vehicles are allowed to change lanes when necessary. The position of each vehicle is updated by using the car-following rules together with the lane-changing rules for the forward motion. Based on the simulated traffic a simple TMM is proposed for VANET simulations, which is capable to identify the vehicles that are in the shadow region of other vehicles. The presented traffic mobility model together with the shadow fading path loss model can take in to account the impact of LOS obstruction on the total received power in the multiple-lane highway scenarios.
Palatal Fistula Post-Cleft Palate Repair: A Tertiary Center Experience in Oman  [PDF]
Amal Al Balushi, Mohudoom Meera Sahib, Taimoor Al Balushi
Modern Plastic Surgery (MPS) , 2017, DOI: 10.4236/mps.2017.73003
Abstract: One of the known complications of cleft palate surgery is development of fistula. This study highlights our experience with cleft palate surgery in relation to fistula occurrence at our center. This is one of the first studies of this kind in Oman. We retrospectively reviewed 362 records of cleft palate patients. The most common technique used for cleft palate repair at our center was Veau-Wardill-Kilner technique. In our series we have noticed palatal fistulae in 32% of cases. This high rate is partially due to inclusion of very anterior fistulas in patients with complete cleft lips and palates, which actually represent part of the alveolar cleft rather than breakdown of the palatal repair. This will be closed during time of alveolar bone grafting at a later stage. We recommend a future prospective controlled study to study the factors that lower the incidence of fistula in our population.
Early Gallbladder Cancer: Clinical, Morphological, Therapeutic and Evolutionary Aspects  [PDF]
Berkane Salah, Abid Larbi
Surgical Science (SS) , 2013, DOI: 10.4236/ss.2013.411095
Abstract:

Introduction: The early cancer of gallbladder is an entity which is not well recognized currently. It is a cancer which does not extend beyond the muscularis layer of the gallbladder and it is characterized in almost of cases by the absence of lymph node and visceral invasion. Patients and Method: We have conducted this retrospective study of all our cases of early gallbladder cancer treated in our surgical unit. We have studied these through clinical, morphological, therapeutical and evolutionary aspects. Results: Of 202 gallbladder carcinoma, 33 cancers were classified as early cancer. 25 were females and 8 were males. The mean age was 56.4 years (4170 years). All patients were free of gallbladder cancer symptoms and all except one had normal CEA and CA19.9. 2 patients had synchronous tumors (one colonic cancer and one rectal cancer). For 16 patients, the diagnosis was done by ultrasonography and 17 by histological examination of the specimen removed for biliary lithiasis. 8 patients had PT1a tumor (confined only to mucosa) and 25 had PT1b tumor (tumor infiltration of the muscular layer). For 19 patients who benefited from extensive lymphadenectomy, only one (5.3%) had lymph node infiltration. 16 patients had a simple cholecystectomy and in two cases, the cholecystectomy was associated with bile duct resection. 17 patients had hepatectomy with extensive lymphadenectomy.

Success Factors of Extracorporeal Shock Wave Lithotripsy (ESWL) for Renal & Ureteric Calculi in Adult  [PDF]
Ammar Fadil Abid
Open Journal of Urology (OJU) , 2014, DOI: 10.4236/oju.2014.43005
Abstract:

The purpose of this study was to define factors that have a significant impact on the stone-free rate after ESWL. Methods: A total of 417 patients harboring renal or ureteral stones underwent extracorporeal shock wave lithotripsy (ESWL) between October 2008 and July 2012. Eighty five patients were lost on follow up. The remaining (n = 332). All patients were >18 yr of age. Siemens and SLX-F2 electromagnetic machines were used to impart shock waves. Patients were stratified according to localization (pelvic, calyceal, or ureteral stones) and stone size (up to 10 mm, 10 - 20 mm, and >20 mm). Result: The overall success rate was 251/332 (75.6%) achieve stone free status. Repeated ESWL sessions were needed in 258 (61.9%). Of eleven variables were studied including age, sex, side, location (pelvic, calyx, ureter), ureteric stent, previous renal surgery, stone size, number of shock waves, opacity of stone, renal system state, and type of lithotripter, three variables were significantly affect the success rate namely stone size, number of shock waves and location of stone. Conclusions: ESWL remains one of the most commonly utilized treatments for patients with upper urinary tract calculi; Stone diameter, location, and number of shock waves, are the most important predictors determining stone clearance after ESWL of renal and ureteric calculi. To optimize treatment outcomes with ESWL the presence of treating urologist is essential to optimize the final result.

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