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Qureshi A.J.,LCFC | Qureshi A.J.,Higher Education Commission | Dantan J.-Y.,LCFC | Bruyere J.,University Claude Bernard Lyon 1 | Bigot R.,LCFC
Engineering Applications of Artificial Intelligence | Year: 2010

Embodiment design is an important phase of the design process where the initial design parameters and their feasible solution spaces with design configurations are decided for the design problem. This article presents a new approach of embodiment design space exploration of the product based on set based design with integration of robustness for the mechanical systems. The approach presented addresses the initial design phase of the mechanical systems design and provides a three step approach based on a formal expression syntax, transformation and evaluation engine and a computational algorithm for performing a domain search for sets of robust solutions for the product designs by taking into the account the variations and uncertainties related to the manufacturing process and material. The approach is based on the design domain exploration and reduction techniques. This is achieved by the utilization and integration of existential and universal quantifiers from the quantifier constraint satisfaction problem (QCSP) for the expression of the parameters and variables related to the product design and robustness. The quantifier notion has been used to develop the consistency check for the existence of a design solution and existence of a robust design solution. In order to compute the developed quantifier approach, an algorithm based on the transformation of the quantifier with interval arithmetic has also been developed. In order to demonstrate the capability of the developed approach, this article includes three examples of mechanical systems from earlier research works that apply the quantifier model and the resolution algorithm to successfully explore the design domain for robust solutions while taking into account different types of variations such as variations in mechanical/material properties, manufacturing variations or variations in geometric dimensions which may be of continuous or discrete type. © 2010 Elsevier Ltd. All rights reserved.

Zafar-ul-Hye M.,Bahauddin Zakariya University | Farooq H.M.,Bahauddin Zakariya University | Zahir Z.A.,University of Agriculture at Faisalabad | Hussain M.,Bahauddin Zakariya University | Hussain A.,Higher Education Commission
International Journal of Agriculture and Biology | Year: 2014

Maize (Zea mays L.) has a lot of dietary and industrial value around the globe and its yield potential is being extremely affected by abiotic stresses i.e., drought and soil salinity/sodicity etc. However, damaging effects of abiotic stresses can be ameliorated by the combined application of plant growth promoting rhizobacteria (PGPR) and mineral fertilizers. Therefore this field trial was designed to explore the effect of PGPR containing ACC deaminase (1-aminocyclopropane-1-carboxylate deaminase) alone and in combination with mineral fertilizers on yield and nutrient uptake of maize under drought in saline field. Two PGPR strains S1 (Pseudomonas syringae) and S2 (Pseudomonas fluorescens) were applied to the maize seeds in separate and along with full and half dose of recommended NPK fertilizers. Drought stress was imposed generally on whole experiment at tasseling by withholding irrigation up to ~50% field capacity (FC) level. The PGPR strains significantly improved the yield of maize when applied alone and further promising results were obtained when applied with mineral fertilizers. Maximum increase in number of cobs plant-1 (19.05%), cob length (68.02%) number of grain rows cob-1 (25.53%), number of grains cob-1 (28.29%) plant height (58.14%), number of grains per cob (28.29%), 1000-grain weight (35.92%) and grain yield (55.14%) was observed by the combined application of PGPR strains and full dose of recommended fertilizers over un-inoculated control and without mineral fertilizers application. Moreover combined application of PGPR strains and mineral fertilizers notably improved the nitrogen (N), phosphorus (P) and potassium (K) contents of grains and stalk of maize not only over control (un-inoculated seed and without mineral fertilizers application) but also over alone application of PGPR strains, and half and full dose of mineral fertilizers application as well. In conclusion, the PGPR strains containing ACC-deaminase activity along with full dose of artificial fertilizers improved the maize productivity due to notable expansion in yield related traits and nutrient uptake under dual stress conditions i.e., drought and soil salinity/sodicity. © 2014 Friends Science Publishers.

Siddique M.,COMSATS Institute of Information Technology | Farooq R.,COMSATS Institute of Information Technology | Khan Z.,Higher Education Commission | Shaukat S.F.,COMSATS Institute of Information Technology
Ultrasonics Sonochemistry | Year: 2011

Textile industry effluents contain reactive dyes that may harm our receiving waters. A typical reactive blue (RB) 19 dye is frequently detected in significant concentrations in textile industry effluents. Such dyes have generally shown resistance to decomposition and tend to persist in the environment for long periods and multiply the impacts to water and environment. Therefore, the present investigation focused on high-rate decomposition of a typical reactive dye RB 19 under various ultrasound and electrochemical process conditions. The decomposition of un-hydrolyzed and hydrolyzed forms of reactive blue (RB) 19 dye by ultrasound assisted electrochemical process was investigated using various parameters including dye concentration, pH, ultrasonic frequency and reaction time. Reaction kinetics, organic carbon and mechanism for dye decomposition were determined using UV-Visible spectrophotometry, TOC (total organic carbon) analysis and gas chromatography-mass spectrometry (GC-MS). Almost complete 90% color removal and a maximum of 56% TOC removal for 50mgL-1 dye concentration of un-hydrolyzed RB 19 dye was achieved at an ultrasonic frequency of 80kHz, pH of 8 after 120min. GC-MS analysis showed that a sonoelectrochemical treatment of un-hydrolyzed RB 19 dye for 30min resulted in the formation of products e.g. acetic acid, benzoic acid etc. with the complete removal of dye. For hydrolyzed dye, a treatment of 10min was enough and the results were comparable with 30min treatment of un-hydrolyzed dye. Kinetics of ultrasound assisted electrolysis showed that the dye decomposition followed 1st order. The ultrasound assisted electrolysis for dye decomposition and hence decolorization proved to be more effective and the total energy consumption reduced to half as compared with simple electrolysis/sonochemical decomposition. Therefore, ultrasound assisted electrolysis was found to be more effective technique for dye decomposition of an otherwise environmentally persistent reactive dye. © 2010.

Khan J.,Sarhad University of Science and Information Technology | Bojkovic Z.S.,University of Belgrade | Marwat M.I.K.,Higher Education Commission
Communications in Computer and Information Science | Year: 2011

Enhancing in performance, strong bandwidth utilization and merging of MANET (3G) and 4G make a plate- form to get best Quality of services. Purpose of this research is to understand the functioning of ad hoc networks and implement proposed routing protocols for mobile ad hoc networks. After analyzing the existing QOS framework with respect to the dynamic and rapidly changing behavior of ad hoc networks. This research attempts to present some of the fundamental routing issues such as decentralization, bandwidth, MANETS delay in DSR and AODV, data delivery ratio in intermediate nodes in static and dynamic position and resource constrained in ad hoc network. Routing of data packets between source to destination is difficult task, So to overcome on these problems we have to extend and evaluate proposed routing protocols (AODV and DSR) suitable for mobile ad hoc networks for best QoS, In order to prove its correctness and efficiency evaluation of the proposed protocols should be done theoretically and implemented through simulation using OPNET simulator. The research will compares the statistics of ad hoc routing protocols by different researches with different simulating tools. 5G can be achieved by making a revolutionary attempt on the basis of this research ideology (merging of ad hoc and cellular technology under 4G umbrella with user centric concept wirelessly with multi terminals at a time), which will assure optimization in the next generation technology. © 2011 Springer-Verlag.

News Article | December 2, 2015

As former chairman of Pakistan's Higher Education Commission and former coordinator-general of the Organisation of Islamic Cooperation's science and technology body COMSTECH, I suggest that some universities in the Muslim world are not in such dire need of revitalization as Nidhal Guessoum and Athar Osama imply (Nature 526, 634–636; 2015). At least 3 such institutions are ranked in the world's top 250 — the University of Malaya in Kuala Lumpur, and King Fahd University and King Saud University, both in Saudi Arabia (see In 2013 and 2014, the Middle East Technical University, Istanbul Technical University and Bilkent University in Turkey were ranked in the top 400 globally (see Pakistan's National University of Sciences and Technology and the Pakistan Institute of Engineering and Applied Sciences were ranked in the top 200 Asian universities in 2014 (see The King Abdullah University of Science and Technology in Saudi Arabia and the Masdar Institute in Abu Dhabi are rising stars. According to 2014 data on scientific publications, Iran ranks 16th in the world, Turkey is 19th and Malaysia is 23rd — on a par with Switzerland, Taiwan and some Scandinavian countries, and ahead of South Africa (see Furthermore, the requirements of the United Arab Emirates' Commission of Academic Accreditation (CAA) are more stringent than those of the US Accreditation Board for Engineering and Technology (ABET), for instance. Whereas the CAA requires faculty members to have the highest degree in their field (such as a PhD), ABET requires only appropriate qualifications. The CAA also requires universities to have accredited PhD programmes in addition to accredited bachelor's and master's degrees.

Alam K.,University of Salzburg | Alam K.,Higher Education Commission | Trautmann T.,German Aerospace Center | Blaschke T.,University of Salzburg | Majid H.,Higher Education Commission
Atmospheric Environment | Year: 2012

The study of aerosol optical and radiative properties presented here focuses on a geographic region in which there exist significant gaps in our knowledge. These properties have been analyzed through the ground-based Aerosol Robotic Network (AERONET) over the two megacities of Lahore and Karachi for summer (April-June) and winter (December-February) of 2010-11. During the study period the monthly mean aerosol optical depth (AOD) at 500nm over Lahore ranged from 0.57±0.18 to 0.76±0.38, and the monthly mean ångström exponent () ranged from 0.39±0.17 to 1.22±0.13. Likewise, over Karachi the monthly mean AOD ranged from 0.33±0.11 to 0.63±0.28 and the values varied between 0.29±0.08 to 0.95±0.22. The average AOD values in summer and winter are 0.66±0.30, 0.50±0.18 and 0.67±0.40, 0.34±0.12 in Lahore and Karachi respectively. The relationship between the Absorption ångström Exponent (AAE) and the Extinction ångström Exponent (EAE) provided an indication of the relative proportions of urban-industrial and mineral dust aerosols over the two sites. The volume size distributions were higher over Lahore than over Karachi during both seasons. The single scattering albedo (SSA) ranged from 0.83±0.02 (440nm) to 0.91±0.05 (1020nm) over Lahore and from 0.88±0.02 (440nm) to 0.97±0.01 (1020nm) over Karachi. The lower SSA values over Lahore suggest that absorbing aerosols are more dominant over Lahore than over Karachi. The average aerosol radiative forcing (ARF) values in summer at the surface and the top of atmosphere (TOA) are-101.6±8.2,-63.3±9.5 and-19±4.35,-20±3.1 over Lahore and Karachi respectively. Likewise, the average ARF values in winter at the surface and TOA are-90.3±21.03,-57±6.35 and-26±7,-16±2.3 over Lahore and Karachi respectively. The averaged aerosol ARF values over Lahore and Karachi for the entire period covered by the observations were-22.5±5.9Wm -2 and-18±2.2Wm -2 at the TOA and-96±13Wm -2 and-60±6.8Wm -2 at the surface, respectively, giving an averaged atmospheric forcing of 74.56±16.8Wm -2 over Lahore and 41.85±6.4Wm -2 over Karachi, which indicates significant heating of the atmosphere at both sites. The average heating rate during summer was 2.3±0.1 and 1.2±0.2Kday -1 and during winter was 1.8±0.4 and 1.1±0.1Kday -1 over Lahore and Karachi respectively. © 2011 Elsevier Ltd.

Qureshi A.J.,Arts et Metiers ParisTech | Qureshi A.J.,Higher Education Commission | Dantan J.-Y.,Arts et Metiers ParisTech | Sabri V.,Arts et Metiers ParisTech | And 3 more authors.
CAD Computer Aided Design | Year: 2012

Tolerancing decisions can profoundly impact the quality and cost of the mechanism. To evaluate the impact of tolerance on mechanism quality, designers need to simulate the influences of tolerances with respect to the functional requirements. This paper proposes a mathematical formulation of tolerance analysis which integrates the notion of quantifier: "For allacceptable deviations (deviations which are inside tolerances),there existsa gap configurationsuch asthe assembly requirements and the behavior constraints are verified" & "For allacceptable deviations (deviations which are inside tolerances), andfor alladmissible gap configurations, the assembly and functional requirements and the behavior constraints are verified". The quantifiers provide a univocal expression of the condition corresponding to a geometrical product requirement. This opens a wide area for research in tolerance analysis. To solve the mechanical problem, an approach based on optimization is proposed. Monte Carlo simulation is implemented for the statistical analysis. The proposed approach is tested on an over-constrained mechanism. © 2011 Elsevier Ltd. All rights reserved.

Ahmad S.S.,Fatima Jinnah Women University | Abbasi Q.,Fatima Jinnah Women University | Jabeen R.,SBKW University | Shah M.T.,Higher Education Commission
Pakistan Journal of Botany | Year: 2012

Deforestation is one of the obstinate environmental problems globally. Pakistan, being a developing nation also encompasses crisis of depletion of forest reserves. The rising climate change consequences remain the primary culprit behind this phenomenon. The present study intends to focus attention on one of the threatened vegetation types, the Conifer forests and their consequent reduction in area during the last two decades. GIS techniques have been employed to analyze the change detection in various regions and provinces of Pakistan. The results of current study indicated that Conifer forests have been declining at the rate of 1.27% per annum since 1992, showing negative trends due to various causes associated with climate change i.e. increase in temperature and decrease in rainfall. So, the need for the conservation of these forests should be the basic task to accomplish order to avoid their vulnerability against various environmental and socio economic disturbances.

Majid H.,University of Salzburg | Majid H.,Higher Education Commission | Hofmann W.,Higher Education Commission | Winkler-Heil R.,Higher Education Commission
Annals of Occupational Hygiene | Year: 2012

Deposition fractions of inhaled particles predicted by different computational models vary with respect to physical and biological factors and mathematical modeling techniques. These models must be validated by comparison with available experimental data. Experimental data supplied by different deposition studies with surrogate airway models or lung casts were used in this study to evaluate the stochastic deposition model Inhalation, Deposition and Exhalation of Aerosols in the Lung at the airway generation level. Furthermore, different analytical equations derived for the three major deposition mechanisms, diffusion, impaction, and sedimentation, were applied to different cast or airway models to quantify their effect on calculated particle deposition fractions. The experimental results for ultrafine particles (0.00175 and 0.01) were found to be in close agreement with the stochastic model predictions; however, for coarse particles (3 and 8 μm), experimental deposition fractions became higher with increasing flow rate. An overall fair agreement among the calculated deposition fractions for the different cast geometries was found. However, alternative deposition equations resulted in up to 300% variation in predicted deposition fractions, although all equations predicted the same trends as functions of particle diameter and breathing conditions. From this comparative study, it can be concluded that structural differences in lung morphologies among different individuals are responsible for the apparent variability in particle deposition in each generation. The use of different deposition equations yields varying deposition results caused primarily by (i) different lung morphometries employed in their derivation and the choice of the central bifurcation zone geometry, (ii) the assumption of specific flow profiles, and (iii) different methods used in the derivation of these equations. © 2012 The Author.

Hussain M.,University of Salzburg | Hussain M.,Higher Education Commission | Renate W.-H.,University of Salzburg | Werner H.,University of Salzburg
Journal of Thoracic Disease | Year: 2011

Objective: The structure of extrathoracic passages, variability of tracheobronchial (TB) airways and alveolar dimensions and individual variations of breathing pattern exhibit significant intersubject variations, which affect extrathoracic deposition and, in further consequence, the fraction of inhaled particles actually reaching the thoracic region. The present study was conducted to quantify the intersubject variability of lung deposition fractions caused by the fluctuations in these three major sources of intersubject variability. Methods: To quantify intersubject variability of extrathoracic, thoracic and total deposition fractions (TDF), different combinations of the three sources of variability were simulated to identify the most important factors. Deposition fractions of inhaled particles were computed by the stochastic airway generation model IDEAL. The dimensions of the respiratory airways were scaled in proportion to age and height of the subject to calculate TDFs. Results: The variability of deposition fractions increased with the stepwise addition of influencing factors and the resulting standard deviations ranged up to 30%. While some combinations enhanced the effects of individual factors on deposition by up to 40%, others seemed to compensate each other with only a minor effect on deposition. Conclusion: The present study attempts to quantify experimentally observed intersubject variability of regional deposition fractions caused by individual variations of nasal and oral geometry, lung airway dimensions and breathing patterns in healthy lungs, serving as a baseline for subsequent calculations for diseased lungs, e.g. asthma, COPD, and emphysema, which may further increase intersubject variabilities of medically relevant depositions. © 2011 Journal of Thoracic Disease.

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