Complex modes in damped sandwich beams using beam and elasticity theories

Ahmad, Naveed,Kapania, Rakesh K. Techno-Press 2015 Advances in aircraft and spacecraft science Vol.2 No.1

We investigated complex damped modes in beams in the presence of a viscoelastic layer sandwiched between two elastic layers. The problem was solved using two approaches, (1) Rayleigh beam theory and analyzed using the Ritz method, and (2) by using 2D plane stress elasticity based finite-element method. The damping in the layers was modeled using the complex modulus. Simply-supported, cantilever, and viscously supported boundary conditions were considered in this study. Simple trigonometric functions were used as admissible functions in the Ritz method. The key idea behind sandwich structure is to increase damping in a beam as affected by the presence of a highly-damped core layer vibrating mainly in shear. Different assumptions are utilized in the literature, to model shear deformation in the core layer. In this manuscript, we used FEM without any kinematic assumptions for the transverse shear in both the core and elastic layers. Moreover, numerical examples were studied, where the base and constraining layers were also damped. The loss factor was calculated by modal strain energy method, and by solving a complex eigenvalue problem. The efficiency of the modal strain energy method was tested for different loss factors in the core layer. Complex mode shapes of the beam were also examined in the study, and a comparison was made between viscoelastically and viscously damped structures. The numerical results were compared with those available in the literature, and the results were found to be satisfactory.

Synthesis, characterization and potential applications of Ag@ZnO nanocomposites with S@g-C₃N₄

Ahmad, Naveed,Javed, Mohsin,Qamar, Muhammad A.,Kiran, Umbreen,Shahid, Sammia,Akbar, Muhammad B.,Sher, Mudassar,Amjad, Adnan Techno-Press 2022 Advances in materials research Vol.11 No.3

It includes the synthesis of pristine ZnO nanoparticles and a series of Ag-doped zinc oxide nanoparticles was carried out by reflux method by varying the amount of silver (1, 3, 5, 7 and 9% by mol.). The morphology of these nanoparticles was investigated by SEM, XRD and FT-IR techniques. These techniques show that synthesized particles are homogenous spherical nanoparticles having an average particle size of about 50-100 nm along with some agglomeration. The photocatalytic activity of the ZnO nanoparticles and Ag doped ZnO nanoparticles were investigated via photodegradation of methylene blue (MB) as a standard dye. The data from the photocatalytic activity of these nanoparticles show that 7% Ag-doped ZnO nanoparticles exhibit much enhanced photocatalytic activity as compared to pristine ZnO nanoparticles and other percentages of Ag-doped ZnO nanoparticles. Furthermore, 7% Ag-doped ZnO was made composites with sulfur-doped graphitic carbon nitride by physical mixing method and a series of nanocomposites were made (3.5, 7.5, 25, 50, 75% by weight). It was observed that the 25% composites exhibited better photocatalytic performance than pristine S-g-C 3 N 4 and pure 7% Ag-doped ZnO. Tauc's plot also supports the photodegradation results.

Irrigation Management in Spring Planted Sunflower (Helianthus annuus L.) sown with Different Planting Methods

Muhammad Shahid,Abdul Khaliq,Naveed Ahmad,Khawar Jabran,Mohsin Zafar,Muhammad Rafiq,Mubshar Hussain 한국국제농업개발학회 2012 韓國國際農業開發學會誌 Vol.24 No.1

This study was conducted to determine the influence of irrigation levels on spring planted sunflower (Helianthus annuus L.) sown with different planting methods. Sunflower was sown either on 60 cm apart single rows on flat seed-bed or on ridges. Three irrigation treatments were I0 (irrigation at early vegetative stage, at bud visible stage, at anthesis and at achene development stage), I1 (irrigation at early vegetative stage, at bud visible stage and at achene development stage) and I2 (irrigation at early vegetative stage, at bud visible stage and at anthesis stage). In I1, irrigation was missing at anthesis and in I2 irrigation was missing at achene development stage. Sunflower yield and yield components showed positive response to ridge sown sunflower with normal four irrigations. Maximum achene yield 3.33 t ha-1 was recorded in ridge sown sunflower with four irrigations. Oil content percentage was highest in case of I0 (42.25%) while the effect of planting methods on oil content was insignificant.

Synthesis and Characterization of Polyaniline-Polyimide Thin-film Composite Membranes for Vegetable Oils/Solvent Separation

Naveed Shahzad Ali,Abdul Ghaffar,Asif Ali Qaiser,Muhammad Ahmad,Khurram 한국고분자학회 2021 폴리머 Vol.45 No.1

The recovery of solvents from the extracted oils using conventional thermal separation processes i.e. distillation or evaporation is often an energy-intensive process. To provide an energy-efficient alternative, an organic solvent nanofiltration thin-film composite membrane was prepared by depositing a thin layer of polyaniline (PANI), a selective layer, via interfacial polymerization on a crosslinked polyimide (XPI), a base ultrafiltration support membrane, to provide selective transport of constituents of a miscella. The membrane was characterized by microscopic, spectroscopic, and thermal analysis. The evaluation of the separation performance was carried out by a dead-end stirred cell using three vegetable oils. For sunflower, corn, and castor oil/n-hexane mixtures, the membrane resulted in a % rejection of 50, 56, and -44, respectively. A comparison of mass flux and rejection of corn and castor oils suggests that the PANI/XPI membranes showed a strong ion-exchange behavior significantly recognizing charge macromolecules due to the presence of charged emeraldine PANI.

영문지(JAST)게재논문 : Sahiwal 젖소의 최적 유생산을 위한 착유방법 측정 연구

( Naveed Aslam ),( Muhammad Abdullah ),( Muhammad Fiaz ),( Jalees Ahmad Bhatti ),( Zeeshan Muhammad Iqbal ),( Nasrullah Bangulzai ),최창원 ( Chang Weon Choi ),조익환 ( Ik Hwan Jo ) 한국동물자원과학회(구 한국축산학회) 2014 축산기술과 산업 Vol.5 No.2

24두의 Sahiwal 젖소를 대상으로 착유횟수와 방법에 의한 생산량 변화를 측정하였다. 선발된 시험축은 완전임의배치법으로 6두씩 4그룹으로 공시되었다. A와 B 그룹의 젖소들은 손 착유법으로 착유하되 각각 일일 2회 및 3회 착유하였고 C와 D그룹의 젖소들은 기계 착유법으로 착유하되, 각각 일일 2회 및 3회 착유 하였다. 전 두수는 동일한 사료와 사양관리 하에서 유지되었다. 건물 섭취량은 일일 3회 착유하는 그룹에서 높게 나타났고 이것은 손 착유법과 기계 착유법 간에도 차이를 보이지 않았다. 일일 2회 착유와 비교해서 일일 3회 착유 시 유량이 높았고(P<0.05), 손 착유법와 기계 착유법 간의 차이는 없었다. 손 착유법과 기계 착유법을 이용한 그룹 모두에서 유지방 비율은 일일 3회 착유보다 2회 착유 시 높게 나타났고(P<0.05), 총고형물 비율 역시 유지방 비율과 비슷한 패턴을 보였다. 하지만, 단백질, 유당, 무지고형물 비율들은 시험구간 유의적 차이를 보이지 않았다(P>0.05). 결론적으로 본 연구결과는 Sahiwal 젖소에 있어서 8시간 간격으로 2회 착유하는 것보다 3회 착유하는 것이 손 착유법이나 기계 착유법 모두에서 유량을 극대화할 수 있는 방법임을 보여주고 있다.

Role of antioxidants in fertility preservation of sperm - A narrative review

Ahmad Yar Qamar,Muhammad Ilyas Naveed,Sanan Raza,Xun Fang,Pantu Kumar Roy,Seonggyu Bang,Bereket Molla Tanga,Islam M. Saadeldin,Sanghoon Lee,Jongki Cho Asian Australasian Association of Animal Productio 2023 Animal Bioscience Vol.36 No.3

Male fertility is affected by multiple endogenous stressors, including reactive oxygen species (ROS), which greatly deteriorate the fertility. However, physiological levels of ROS are required by sperm for the proper accomplishment of different cellular functions including proliferation, maturation, capacitation, acrosomal reaction, and fertilization. Excessive ROS production creates an imbalance between ROS production and neutralization resulting in oxidative stress (OS). OS causes male infertility by impairing sperm functions including reduced motility, deoxyribonucleic acid damage, morphological defects, and enhanced apoptosis. Several in-vivo and in-vitro studies have reported improvement in quality-related parameters of sperm following the use of different natural and synthetic antioxidants. In this review, we focus on the causes of OS, ROS production sources, mechanisms responsible for sperm damage, and the role of antioxidants in preserving sperm fertility.

RESEARCH : Open Access ; Evaluation of different milking practices for optimum production performance in Sahiwal cows

( Naveed Aslam ),( Muhammad Abdullah ),( Muhammad Fiaz ),( Jalees Ahmad Bhatti ),( Zeeshan Muhammad Iqbal ),( Nasrullah Bangulzai ),( Chang Weon Choi ),( Ik Hwan Jo ) 한국동물자원과학회(구 한국축산학회) 2014 한국축산학회지 Vol.56 No.13

The production performance of multiparous lactating Sahiwal cows (n = 24) was evaluated according to both milking frequency and method. Selected animals were randomly divided into four groups containing six animals each under a completely randomized design. Cows in groups A & B were milked by the hand milking method three times per day, respectively. Similarly, cows in groups C & D were milked by the machine milking method two and three times per day, respectively. All animals were maintained under uniform feeding and management conditions. Dry matter intake was high in animal groups milked three times per day, and it remained unchanged between the hand and machine milking methods. Milk yield was higher (P < 0.05) in cows milked three times compared to those milked twice per day, and it did not differ between hand and machine milking methods. Milk fat percentage was higher (P < 0.05) in cows milked twice per day compared to those milked three times using both machine and hand milking methods. The percentage of total solids showed a similar pattern as the fat percentage. However, percentages of protein, lactose, and non-fat solids in milk were not significantly different(P > 0.05) among the treatment groups. Collectively, the results show that milking three times per day instead of twice at 8-hour intervals can enhance milk yield in Sahiwal cows using both hand and machine milking methods.

Evaluation of different milking practices for optimum production performance in Sahiwal cows

Aslam, Naveed,Abdullah, Muhammad,Fiaz, Muhammad,Bhatti, Jalees Ahmad,Iqbal, Zeeshan Muhammad,Bangulzai, Nasrullah,Choi, Chang Weon,Jo, Ik Hwan Korean Society of Animal Sciences and Technology 2014 한국축산학회지 Vol.56 No.4

The production performance of multiparous lactating Sahiwal cows (n = 24) was evaluated according to both milking frequency and method. Selected animals were randomly divided into four groups containing six animals each under a completely randomized design. Cows in groups A & B were milked by the hand milking method three times per day, respectively. Similarly, cows in groups C & D were milked by the machine milking method two and three times per day, respectively. All animals were maintained under uniform feeding and management conditions. Dry matter intake was high in animal groups milked three times per day, and it remained unchanged between the hand and machine milking methods. Milk yield was higher (P < 0.05) in cows milked three times compared to those milked twice per day, and it did not differ between hand and machine milking methods. Milk fat percentage was higher (P < 0.05) in cows milked twice per day compared to those milked three times using both machine and hand milking methods. The percentage of total solids showed a similar pattern as the fat percentage. However, percentages of protein, lactose, and non-fat solids in milk were not significantly different (P > 0.05) among the treatment groups. Collectively, the results show that milking three times per day instead of twice at 8-hour intervals can enhance milk yield in Sahiwal cows using both hand and machine milking methods.

Adsorption of methyl orange using self-assembled porous microspheres of poly(o-chloroaniline)

Muhammad Naveed Anjum,Heqing Tang,Mohammad Zuber,Khalid Mahmood Zia,Lihua Zhu,Haroon-ur-Rashid,Mirza Nadeem Ahmad 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.12

Self-assembled hollow microspheres poly(o-chloroaniline) (POC) have been synthesized by simple oxida-tive polymerization of o-chloroaniline using camphor-sulfonic acid (CSA) as dopant acid and ammonium persulfate(APS) as oxidant. The POC microspheres were characterized by means of FTIR, XRD and SEM analysis. Adsorptioncharacteristics of POC spheres were studied by using methyl orange (MO) as adsorbate. It was found that adsorptionof MO by POC was better described by pseudo-second-order kinetics than any other kinetic model, such as the pseudo-first-order and intra-particle diffusion models. Langmuir adsorption isotherm model was the best to fit experimentaldata. The results showed that hollow microspheres of POC can be used as novel and low-cost adsorbent for removalof organic dye from waste water.

Arabic Words Extraction and Character Recognition from Picturesque Image Macros with Enhanced VGG-16 based Model Functionality Using Neural Networks

Ayed Ahmad Hamdan Al-Radaideh,Mohd Shafry bin Mohd Rahim,Wad Ghaban,Majdi Bsoul,Shahid Kamal,Naveed Abbas 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.7

Innovation and rapid increased functionality in user friendly smartphones has encouraged shutterbugs to have picturesque image macros while in work environment or during travel. Formal signboards are placed with marketing objectives and are enriched with text for attracting people. Extracting and recognition of the text from natural images is an emerging research issue and needs consideration. When compared to conventional optical character recognition (OCR), the complex background, implicit noise, lighting, and orientation of these scenic text photos make this problem more difficult. Arabic language text scene extraction and recognition adds a number of complications and difficulties. The method described in this paper uses a two-phase methodology to extract Arabic text and word boundaries awareness from scenic images with varying text orientations. The first stage uses a convolution auto-encoder, and the second uses Arabic Character Segmentation (ACS), which is followed by traditional two-layer neural networks for recognition. This study presents the way that how can an Arabic training and synthetic dataset be created for exemplify the superimposed text in different scene images. For this purpose a dataset of size 10K of cropped images has been created in the detection phase wherein Arabic text was found and 127k Arabic character dataset for the recognition phase. The phase-1 labels were generated from an Arabic corpus of quotes and sentences, which consists of 15kquotes and sentences. This study ensures that Arabic Word Awareness Region Detection (AWARD) approach with high flexibility in identifying complex Arabic text scene images, such as texts that are arbitrarily oriented, curved, or deformed, is used to detect these texts. Our research after experimentations shows that the system has a 91.8% word segmentation accuracy and a 94.2% character recognition accuracy. We believe in the future that the researchers will excel in the field of image processing while treating text images to improve or reduce noise by processing scene images in any language by enhancing the functionality of VGG-16 based model using Neural Networks.