Regulation control of a dc motor by -PID controller based on the frequency response analysis

Alhassan Dodo Adamou Soudeize,박지선,최호림 한국전기전자학회 2023 전기전자학회논문지 Vol.27 No.4

In this paper, we propose an alternative analysis to regulate DC motors using a PID controller with a gainscaling factor. We start by providing a systematic design method for selecting the PID gains of our proposedcontroller by seeing the effect of  on damping ratio, overshoot and settling time from the frequency responseanalysis. With the help of matlab (simulink), We proceed to show that the proposed controller provides robuststability against system parameter uncertainty and the effect of the gain scaling factor on steady-state error. Thevalidity of our control method along with the analysis is verified with the simulation results.

DETERMINANTS AND CONSEQUENCES OF CONSUMERS’ ATTITUDES TOWARD ONLINE PRODUCT REVIEWS

Alhassan G. Mumuni,Karen M. Lancendorfer,Kelley O’Reilly,Amy MacMillan 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

In today’s Internet society, consumers value the opinion of other consumers, and regularly seek feedback on products and services prior to making purchase decisions. This consumer-to-consumer communication (C2C) commonly occurs online, and is referred to as electronic word-of-mouth (eWOM). One popular source of eWOM is online product reviews. The current research investigates the determinants of consumers’ attitudes toward online product reviews. Results indicate that perceived value and credibility of online product reviews positively impact consumer attitudes towards online product reviews. More specifically, consumers’ attitudes toward online product reviews positively influence their reliance on said reviews prior to product purchase. Additionally consumers’ attitudes toward online product reviews are positively determined by their perceptions of the credibility of online product reviews and the value of those reviews. However, the perceived value of online product reviews have a greater impact on online review attitudes than does perceived credibility of online product reviews. Further, men and women exhibit differences in their attitudes and reliance regarding online product reviews.

Acute phase protein mRNA expressions and enhancement of antioxidant defense system in Black-meated Silkie Fowls supplemented with clove (Eugenia caryophyllus) extracts under the influence of chronic heat stress

( Alhassan Usman Bello ),( Jelilat Aderonke Sulaiman ),( Madagu Samaila Aliyu ) 한국동물자원과학회(구 한국축산학회) 2016 한국축산학회지 Vol.58 No.11

Background: The current study investigates the anti-stress effects of clove (Eugenia caryophyllus) extracts (0, 200, 400, and 600 mg/kg) on serum antioxidant biomarkers, immune response, immunological organ growth index, and expression levels of acute phase proteins (APPs); ovotransferrin (OVT), ceruloplasmin (CP), ceruloplasmin (AGP), C-reactive protein (CRP), and serum amyloid-A (SAA) mRNA in the immunological organs of 63-d-old male black-meated Silkie fowls subjected to 21 d chronic heat stress at 35 ± 2 °C. Results: The results demonstrated that clove extract supplementation in the diet of Silkie fowls subjected to elevated temperature (ET) improve growth performance, immune responses, and suppressed the activities of glutathion peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), and thioredoxin reductase (TXNRD); reduced serum malonaldehyde (MDA) and glutathione (GSH) concentrations when compared with fowls raised under thermoneutral condition (TC). Upon chronic heat stress and supplementation of clove extracts, the Silkie fowls showed a linear increase in GSH-Px, SOD, CAT, and TXNRD activities (P = 0.01) compared with fowls fed diets without clove extract. ET decreased (P < 0.05) the growth index of the liver, spleen, bursa of Fabricius and thymus. However, the growth index of the liver, spleen, bursa of Fabricius and thymus increased significantly (P < 0.05) which corresponded to an increase in clove supplemented levels. The expression of OVT, CP, AGP, CRP, and SAA mRNA in the liver, spleen, bursa of Fabricius and thymus were elevated (P < 0.01) by ET compared with those maintained at TC. Nevertheless, clove mitigates heat stress-induced overexpression of OVT, CP, AGP, CRP and SAA mRNA in the immune organs of fowls fed 400 mg clove/kg compared to other groups. Conclusions: The results showed that clove extracts supplementation decreased oxidative stress in the heat-stressed black-meated fowls by alleviating negative effects of heat stress via improvement in growth performance, antioxidant defense mechanisms, immunity, and regulate the expression of acute phase genes in the liver and immunological organs.

Concerning the tensor-based flexural formulation: Applications

Mohammed A. Alhassan,Rajai Z. Al-Rousan,Moheldeen A. Hejazi 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.77 No.6

Recently, the plate bending analysis has been interpreted in terms of the tensor’s components of curvatures and bending moments by presenting the conceptual perspectives of the Hydrostatic Method of Analysis (HM) and theoretical formulations that combine the continuum mechanics with the graphical statics analysis, the theory of thin orthotropic and isotropic plates, and the elasticity theory. In pursuance of uncovering a genuine formulation of the plate’s flexural differential equations, that possess the general-covariance and coordinates-independency. This study had then, tackled various natural and structural problems in both solid and fluid branches of the continuum mechanics in a description of such theoretical and conceptual attainment in uncovering the dimensional independent diffeomorphism covariant partial differential laws.

Enhancing the Performance of Coherent Sources SAC OCDMA Networks via Spatial Multiplexing

Ahmed M. Alhassan,Nasreen Badruddin,Naufal M. Saad,Syed A. Aljunid 한국광학회 2013 Current Optics and Photonics Vol.17 No.6

The beating of two or more lasers that have the same or a finite difference in the central frequencies,is the main source of noise in spectral amplitude coding optical code division multiple access (SACOCDMA) systems. In this paper we adopt a spatial multiplexing (SM) scheme for SAC OCDMA systemsto mitigate this beat noise. The results show that for different code weights and different data rates SMSAC can support a larger number of users than the conventional SAC for all different laser sourceconfigurations. However, SM SAC requires a more complex system than the conventional SAC, and almosttwice as much optical component.

Solvent free cyclodehydration of sorbitol to isosorbide over mesoporous sulfated titania with enhanced catalytic performance

Dabbawala, Aasif A.,Alhassan, Saeed M.,Mishra, Dinesh K.,Jegal, Jonggeon,Hwang, Jin-Soo Elsevier 2018 Molecular catalysis Vol.454 No.-

<P>Mesoporous sulfated titania (MST), a solid acid catalyst has been prepared in one step by organic template free straightforward hydrolysis of titanium oxysulfate and subsequent calcination at different temperatures. The resultant nano-sized MST catalysts showed remarkable catalytic performances in solvent free cyclodehydration of sorbitol as compared to sulfated TiO2 prepared by conventional method. The catalyst activity of MST catalysts varied with calcination temperature and MST-450 (calcined at 450 degrees C) exhibited highest catalytic activity and isosorbide selectivity. The MST-450 catalyzed this dehydration reaction at comparatively lower reaction temperature and produced isosorbide with high selectivity in short reaction time. The complete conversion of sorbitol with 70% isosorbide selectivity was achieved in 2 h at 180 degrees C. The high catalytic activity of MST catalyst attributes to its high specific surface area, large pore size and hence facile diffusion of reactants into the pores and ease to access acid sites. Moreover, the effects of calcination temperature, sulfur content, catalyst amount, reaction temperature and reaction time on conversion and selectivity were studied and the catalyst was also reused.</P>

Concerning the tensor-based flexural formulation: Theory

Rajai Z. Al-Rousan,Mohammed A. Alhassan,Moheldeen A. Hejazi 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.70 No.4

Since the days of yore, plate\'s flexural analysis and formulation were dependent on the assumed coordinate system. In uncovering the coordinates-independent flexural interpretation, in this study, the plate bending analysis has been interpreted in terms of the tensor\'s components of curvatures and bending moments, in accordance with the continuum mechanics. The paper herein presents the theoretical formulations and conceptual perspectives of the Hydrostatic Method of Analysis (HM) that combines the continuum mechanics with the elasticity theory; the graphical statics and analysis; the theory of thin isotropic and orthotropic plates.

Impact resistance of polypropylene fiber reinforced concrete two-way slabs

Rajai Z. Al-Rousan,Mohammed A. Alhassan,Harith Al-Salman 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.62 No.3

Concrete structures are often subjected to long-term static and short-term dynamic loads. Due to a relatively low tensile strength and energy dissipating characteristics, the impact resistance of concrete is considered poor. This study investigates the feasibility of using polypropylene fibers to improve the impact resistance of reinforced concrete slabs. Fourteen polypropylene fiber reinforced concrete slabs were fabricated and tested using a drop weight test. The effects of slab thickness, fiber volume fractions, and impact energy on the dynamic behaviors were evaluated mainly in terms of impact resistant, crack patterns, and failure modes. The post impact induced strains versus time responses were obtained for all slabs. The results showed that adding the polypropylene fiber at a dosage of 0.90% by volume of concrete leads to significant improvement in the overall structural behavior of the slabs and their resistance to impact loading. Interestingly, the enhancement in the behavior of the slabs using a higher fiber dosage of 1.2% was not as good as achieved with 0.90%.

Novel nonlinear stiffness parameters and constitutive curves for concrete

Rajai Z. Al-Rousan,Mohammed A. Alhassan,Moheldeen A. Hejazi 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.22 No.6

Concrete is highly non-linear material which is originating from the transition zone in the form of micro-cracks, governs material response under various loadings. In this paper, the constitutive models published by many researchers have been used to generate novel stiffness parameters and constitutive curves for concrete. Following such linear material formulations, where the energy is conservative during the curvature, and a nonlinear contribution to the concrete has been made and investigated. In which, nonlinear concrete elastic modulus modeling has been developed that is capable-of representing concrete elasticity for grades ranging from 10 to 140 MPa. Thus, covering the grades range of concrete up to the ultra-high strength concrete, and replacing many concrete models that are valid for narrow ranges of concrete strength grades. This has been followed by the introduction of the nonlinear Hooke’s law for the concrete material through the replacement of the Young constant modulus with the nonlinear modulus. In addition, the concept of concrete elasticity index (φ) has been proposed and this factor has been introduced to account for the degradation of concrete stiffness in compression under increased loading as well as the multi-stages micro-cracking behavior of concrete under uniaxial compression. Finally, a sub-routine artificial neural network model has been developed to capture the concrete behavior that has been introduced to facilitate the prediction of concrete properties under increased loading.

Ru–NiO<i>x</i> nanohybrids on TiO₂ support prepared by impregnation-reduction method for efficient hydrogenation of lactose to lactitol

Mishra, Dinesh Kumar,Dabbawala, Aasif A.,Truong, Cong Chien,Alhassan, Saeed M.,Jegal, Jonggeon,Hwang, Jin Soo Elsevier 2018 Journal of industrial and engineering chemistry Vol.68 No.-

<P><B>Abstract</B></P> <P>Lactose is a reducing disaccharide consisting of two different monosaccharides such as galactose and glucose. The hydrogenation of lactose to lactitol is a formidable challenge because it is a complex process and several side products are formed. In this work, we synthesized Ru–Ni bimetallic nanohybrids as efficient catalysts for selective lactose hydrogenation to give selective lactitol. Ru–Ni bimetallic nanohybrids with Ru–NiO<I> <SUB>x</SUB> </I> (<I>x</I> =1, 5, and 10wt%) are prepared by impregnating Ru and Ni salts precursors with TiO<SUB>2</SUB> used as support material. Ru–Ni bimetallic nanohybrids (represented as 5Ru–5NiO/TiO<SUB>2</SUB>) catalyst is found to exhibit the remarkably high selectivity of lactitol (99.4%) and turnover frequency i.e. (374h<SUP>−1</SUP>). In contrast, monometallic Ru/TiO<SUB>2</SUB> catalyst shows poor performance with (TOF=251h<SUP>−1</SUP>). The detailed characterizations confirmed a strong interaction between Ru and NiO species, demonstrating a synergistic effect on the improvement on lactitol selectivity. The impregnation-reduction method for the preparation of bimetallic Ru–NiO/TiO<SUB>2</SUB> catalyst promoted Ru nanoparticles dispersed on NiO and intensified the interaction between Ru and NiO species. Ru–NiO/TiO<SUB>2</SUB> efficiently catalyzed the hydrogenation of lactose to lactitol with high yield/selectivity at almost complete conversion of lactose at 120°C and 55bar of hydrogen (H<SUB>2</SUB>) pressure. Moreover, Ru–NiO/TiO<SUB>2</SUB> catalyst could also be easily recovered and reused up to four runs without notable change in original activity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Highly active supported Ru–Ni bimetallic catalysts with NiO are prepared. </LI> <LI> Bimetallic Ru–5NiO/TiO<SUB>2</SUB> catalyst shows high selectivity to lactitol (99.4%). </LI> <LI> Optimization and kinetics studies of lactose hydrogenation. </LI> <LI> Bimetallic Ru–5NiO/TiO<SUB>2</SUB> catalyst is reused up to several consecutive times. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>