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Muhammad Ahsan Sami,Muhammad Umar Masood,Muhammad Waqar,Muhammad Mujtaba,Abrahim Ali Shah,Nasir Rashid,Mohsin I. Tiwana,Javaid Iqbal,Adnan Shujah 제어로봇시스템학회 2017 제어로봇시스템학회 국제학술대회 논문집 Vol.2017 No.10
This paper presents an application of a novel approach for detecting and tracking an object with a 2 DOF robotic manipulator which can be equipped with an array of electrically controlled actuators. The said approach utilizes the Image Based Visual Servoing (IBVS) technique. The developed system is able to determine the object pose in real time from features in the image. Object is detected using shaped based approach algorithms of image processing. The position and orientation of the world coordinates of the object being tracked are calculated from the coordinates of the object in image plane using camera’s intrinsic and extrinsic parameters. Experimental results demonstrate the effectiveness of this proposed approach.
Muhammad Nabeel,Muhammad Ali Nasir,Mariyam Sattar,Rizwan Ahmed Malik,Meshal Alzaid,Muhammad Shoaib Butt,Mohsin Saleem,Hussein Alrobei 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.11
Flexural, tensile, and impact strength of hybrid Kevlar/glass reinforced epoxy composite is studied. Six different types of hybrid composite material were manufactured by hand layup process using different compositions of Kevlar and glass fiber. Tensile, flexural and impact strengths of manufactured samples were investigated using standard tests and compared. It is observed that tensile strength is greater for combinations with higher percentage (%) of Kevlar fabric and decreases with an increase in the glass fabric %age. Flexural strength is higher for combinations with greater %age of glass fabric and decreases with an increase in the Kevlar fabric %age. From drop weight test, it is found from visual inspection that damaged area is increased with an increase in the glass fabric percentage. Numerical simulation model incorporated with elastoplastic material data successfully predicts tensile and flexural experimental results.
Nasir, Muhammad Tauseef,Ali, Muhammad Ansab,Khan, Tariq S.,Al-Hajri, Ebrahim,Kadri, Muhammad Bilal,Kim, Kyung Chun Elsevier Sequoia S.A 2019 Energy and buildings Vol.191 No.-
<P><B>Abstract</B></P> <P>Present work aims to investigate the thermal performance assessment of different combinations of working fluids for an Organic Rankine Cycle powered Vapor Compression Cycle (ORC-VCC) for air-conditioning applications. Analysis of system performance is conducted for a fixed cooling load of a small conditioned space having a sensible heat factor of 0.7, at different ambient conditions. A preliminary evaluation of the system at the baseline conditions was conducted considering the second law efficiency, overall heat capacity of exchangers, overall internal exergy destruction, and overall Coefficient of Performance. Afterwards, parametric study was performed for the best performing candidates from the preliminary analysis using second law efficiency and overall heat capacity of heat exchangers. The system parameters considered for the study include saturated temperatures of heat exchangers, ORC boiler superheat, pinch points and the sub-cooling of both the ORC and VCC condensers. Then, multi objective optimization was performed using Genetic Algorithm followed by multi-criteria decision-making using Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) to select the best optimal solutions from the Pareto front. Sixteen combinations comprising of four working fluids, R245fa, R600, R600a, and R134a were analyzed. The optimization results showed R245fa ORC-R600a VCC to be the best candidate at ambient conditions of 30 °C, while at 35 °C and 40 °C, R600a ORC-R245fa VCC was found to be the most suitable candidate.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The prospects of different working fluids and their combinations in an ORC driven air conditioning system are investigated. </LI> <LI> Ambient conditions considering the outdoor temperatures of 30 °C, 35 °C and 40 °C with 50% relative humidity is selected. </LI> <LI> Working fluids R245fa, R134a, R600a, and R600, and their combinations are the investigated. </LI> <LI> Sensitivity analysis of different parameters on the second law efficiency and UA values of heat exchangers is evaluated. </LI> <LI> Multi-objective optimization of the exergetic efficiency and the UA values of heat exchangers is carried out. </LI> </UL> </P>
Twisted non-diffracting beams through all dielectric meta-axicons
Mahmood, Nasir,Jeong, Heonyeong,Kim, Inki,Mehmood, Muhammad Qasim,Zubair, Muhammad,Akbar, Ali,Saleem, Murtaza,Anwar, Muhammad Sabieh,Tahir, Farooq Ahmad,Rho, Junsuk The Royal Society of Chemistry 2019 Nanoscale Vol.11 No.43
<P>We demonstrate transmission-based all-dielectric, highly efficient (≈73.4%) and polarization-insensitive meta-axicons (for the visible wavelength of 633 nm) to generate zero and higher order Bessel beams without using additional components. The Bessel beams, owing to their diverse applications and non-diffractive properties, attract great interest from the scientific community. It is shown that the propagation length can be increased through a lower numerical aperture (∼2600 <I>λ</I> for NA = 0.1) whereas a higher full width at half maximum (< 0.5 <I>λ</I>) can be obtained for a higher numerical aperture (for NA ≥ 0.7). Our dielectric material, hydrogenated amorphous silicon (a-Si:H), provides a significant efficiency advantage over plasmonic and other high-index all-dielectric (<I>e.g.</I>, TiO2 and GaN) metasurfaces in terms of cost, ease of fabrication, and CMOS compatibility. The finite difference time domain (FDTD) technique based numerically simulated and experimental results show excellent agreement. Due to the technological and scientific importance of the Bessel beams, the recommended material and meta-axicons provide an efficient and compact platform for realizing various advanced applications like optical manipulation, optical alignment, laser fabrication, imaging, and laser machining.</P>
Polarisation insensitive multifunctional metasurfaces based on all-dielectric nanowaveguides
Mahmood, Nasir,Kim, Inki,Mehmood, Muhammad Qasim,Jeong, Heonyeong,Akbar, Ali,Lee, Dasol,Saleem, Murtaza,Zubair, Muhammad,Anwar, Muhammad Sabieh,Tahir, Farooq Ahmad,Rho, Junsuk The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.38
<P>Metasurfaces, two dimensional (2D) metamaterials comprised of subwavelength features, can be used to tailor the amplitude, phase and polarisation of an incident electromagnetic wave propagating at an interface. Though many novel metasurfaces have been explored, the hunt for cost-effective, highly efficient, low-loss and polarisation insensitive applications is ongoing. In this work, we utilise an efficient and cost-effective dielectric material, hydrogenated amorphous silicon (a-Si:H), to create a ultra-thin transmissive surface that simultaneously controls phase. This material exhibits significantly lower absorption in the visible regime compared to standard amorphous silicon, making it an ideal candidate for various on-chip applications. Our proposed design, which works on the principle of index waveguiding, integrates two distinct phase profiles, that of a lens and of a helical beam, and is versatile due to its polarisation-insensitivity. We show how this metasurface can lead to highly concentrated optical vortices in the visible domain, whose focused ring-shaped profiles carry orbital angular momentum at the miniaturised scale.</P>
Aakash Ali,Muhammad Ali Nasir,Muhammad Yasir Khalid,Saad Nauman,Khubab Shaker,Shahab Khushnood,Khurram Altaf,Muhammad Zeeshan,Azhar Hussain 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.9
Natural fiber composites have great potential for reducing the product cost, lowering weight and enhancing renewability. Functionality and performance of natural fibers can be enhanced many folds using them together with synthetic fibers. Hybridization of carbon and low-cost natural jute fiber offers a sustainable hybrid composite having high modulus and mechanical strength. This study investigates flexural behavior of carbon/jute epoxy composites experimentally and numerically. Also, impact response is characterized through drop weight method. Study concludes that flexural strength decreases with increase in jute percentage. Simulation of flexural behavior diverges more than 10 % from experimental results. This anomaly is due to waviness of fiber resulting in heterogeneous property distribution in composites. Further, the fracto-graphic study revealed modes of failure. The drop weight impact tests reveal increased damage area with increase in jute percentage.
Abdul Haleem,Sidra Bibi Syaal,Muhammad Ajmal,Jaweria Ambreen,Sajid Rauf,Nasir Ali,Saz Muhammad,Afzal Shah,Muhammad Abid Zia,Muhammad Siddiq 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.4
Here in, we demonstrate facile fabrication of silver and palladium nanoparticles in dual responsive poly(Nisopropylacrylamide- co-2-Acrylamido-2-methylpropane sulfonic acid) microgel with temperature- and pH-dependent catalytic potential. Palladium-based catalyst showed better catalytic efficiency as compared to silver-based catalyst for degradation of Rhodamine-B and P-Nitrophenol in aqueous medium under the same set of reaction conditions. The responsive nature of the microgel was found to be useful to tune the catalytic activity of the as-prepared catalysts, and reduction rate was enhanced with the pH and temperature elevation of the reaction medium; however, the increasing trend was slowed in the volume phase transition region of the microgel. Under a specific set of reaction conditions, the reduction of Rhodamine-B was as fast as 0.968 and 0.571 min1 when catalyzed with palladium and silver based catalysts, respectively. The hydrodynamic radius of the particles of microgel support was found to be in the range of 65- 180 nm when pH and temperature of the medium were varied in the range of 2-12 and 25-45, respectively. The estimated diameter of silver and palladium nanoparticles fabricated in the microgel support under the same set of reaction conditions was 9-15 and 7-11 nm, respectively.
Nasir Shabab,Walters Keith F.A.,Pereira Roberto M.,Waris Muhammad,Ali Chatha Awais,Hayat Munawar,Batool Marriam 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.3
Mosquito vectors of major human diseases are currently controlled using chemical and biological products. Extensive insecticide use has led to resistance development and human/environmental health risks, and alter native sustainable control options are needed; in this study, activity of an extract of garlic (Allium sativum; Amaryllidaceae), and silver nanoparticles (AgNPs) synthesized from the extract, were evaluated against 2nd and 3rd instar larvae of the yellow fever mosquito, Ae. aegypti (Diptera: Culicidae). Synthesis of AgNPs was confirmed using UV–Vis spectroscopy, and characterised using powdered X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Larvae were exposed to five concentrations (50, 100, 150, 200, 250 ppm) of garlic extract or synthesized AgNPs, with distilled water and silver nitrate solution (1 mM) as controls. The mortality of larvae was recorded after 6, 12, 24, 36, and 48 h following addition of the respective extracts. Dose- and time-dependent toxicity were recorded in both treatment groups with no mortality in control groups. Exposure to AgNPs at 250 ppm for 48 h yielded 100% mortality for both larval instars, with corre sponding LC 50 values of 44.77 (2nd) and 62.82 ppm (3rd). Exposure to garlic extract resulted in similar 48-hour mortality (99 ± 0.77% (2nd) and 98 ± 1.10% (3rd), but consistently higher LC 50 values after all exposure times compared to AgNPs (e.g. 48-hour exposure: 108.42 ppm (2nd), 129.11 ppm (3rd), suggesting that AgNPs may potentially be used at lower concentrations for Ae. aegypti control.
Ali, Gowhar,Subhan, Fazal,Islam, Nazar Ul,Ullah, Nasir,Shahid, Muhammad,Ullah, Sami,Ullah, Ihsan,Shah, Rehmat,Khan, Ikhtiar,Sewell, Robert D. E.,Abbas, Ghulam 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7
The aim of the current study was to explore in vivo any relative gastroulcerogenic prospective propensity of newly synthesized nitrogen containing derivatives of salicyl alcohol; compound (I) [1-(2-hydroxybenzyl) piperidinium chloride], compound (II) [4-carbamoyl-1-(2- hydroxybenzyl)piperidinium chloride] and aspirin in albino rats. The experimental groups received the following oral treatments daily for 6 days: group I saline control; group II, standard (aspirin) treatment group [150 mg/kg of body weight]; group III, test (compound I) treatment group [100, 150 mg/kg]; group IV, test (compound II) treatment group [100, 150 mg/kg]. The results showed that in the case of the aspirin treated group and compound (I) [150 mg/kg], there was a significant increase in gastric volume, free acidity, total acidity, ulcer score and a decrease in gastric pH. Furthermore, histopathological examination of gastric mucosa of these treated groups revealed detectable morphological changes. Utilizing the same protocol, synthetic compound (I) [100 mg/kg] and (II) [100, 150 mg/kg] exhibited no statistically significant ulcerogenic or cytotoxic properties. A cyclooxygenase (COX) selectivity test indicated the preferential inhibition of COX-I and COX-II enzymes by compounds (I) and (II). This study therefore indicates that these synthetic compounds may possess reduced ulcerogenic potential and could be a functional substitute to aspirin.
Gowhar Ali,Fazal Subhan,Nazar Ul Islam,Nasir Ullah,Muhammad Shahid,Sami Ullah,Ihsan Ullah,Rehmat Shah,Ikhtiar Khan,Robert D. E. Sewell,Ghulam Abbas 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7
The aim of the current study was to explorein vivo any relative gastroulcerogenic prospective propensityof newly synthesized nitrogen containing derivativesof salicyl alcohol; compound (I) [1-(2-hydroxybenzyl)piperidinium chloride], compound (II) [4-carbamoyl-1-(2-hydroxybenzyl)piperidinium chloride] and aspirin in albinorats. The experimental groups received the following oraltreatments daily for 6 days: group I saline control; group II,standard (aspirin) treatment group [150 mg/kg of bodyweight]; group III, test (compound I) treatment group [100,150 mg/kg]; group IV, test (compound II) treatment group[100, 150 mg/kg]. The results showed that in the case of theaspirin treated group and compound (I) [150 mg/kg], therewas a significant increase in gastric volume, free acidity,total acidity, ulcer score and a decrease in gastric pH. Furthermore, histopathological examination of gastricmucosa of these treated groups revealed detectable morphologicalchanges. Utilizing the same protocol, syntheticcompound (I) [100 mg/kg] and (II) [100, 150 mg/kg]exhibited no statistically significant ulcerogenic or cytotoxicproperties. A cyclooxygenase (COX) selectivity test indicatedthe preferential inhibition of COX-I and COX-IIenzymes by compounds (I) and (II). This study thereforeindicates that these synthetic compounds may possessreduced ulcerogenic potential and could be a functionalsubstitute to aspirin.