Search results for: Mahmood Ameen Abdulla
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 211

Search results for: Mahmood Ameen Abdulla

121 Knowledge Management and Motivation Management: Important Constituents of Firm Performance

Authors: Yassir Mahmood, Nadia Ehsan

Abstract:

In current research stream, empirical work regarding knowledge and motivation management along their dimensions is sparse. This study partially filled this void by investigating the influence of knowledge management (tacit and explicit) and motivation management (intrinsic and extrinsic) on firm performance with the mediating effects of innovative performance. Based on the quantitative research method, data were collected through questionnaire from 284 employees working in 18 different firms across the citrus industry located in Sargodha region (Pakistan). The proposed relationships were tested through regression analysis while mediation relations were analyzed through Barron and Kenny (1986) technique. The results suggested that knowledge management (KM) and motivation management (MM) have significant positive impacts on innovative performance (IP). In addition, the role of IP as full mediator between KM and firm performance (FP) is confirmed. Also, IP proved to be a partial mediator between MM and FP. From the managerial perspective, the findings of the study are vital as some of the important constituents of FP have been highlighted. The study produced important underpinnings for managers. In last, implications for policymakers along with future research directions are discussed.

Keywords: innovative performance, firm performance, knowledge management, motivation management, Sargodha

Procedia PDF Downloads 127
120 Unreality of Real: Debordean Reading of Gillian Flynn's Gone Girl

Authors: Sahand Hamed Moeel Ardebil, Zohreh Taebi Noghondari, Mahmood Reza Ghorban Sabbagh

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Gillian Flynn’s Gone Girl, depicts a society in which, as a result of media dominance, the reality is very precarious and difficult to grasp. In Gone Girl, reality and image of reality represented on TV, are challenging to differentiate. Along with reality, individuals’ agency and independence before media and the capitalist rule are called in to question in the novel. In order to expose the unstable nature of reality and an individual’s complicated relationship with media, this study has deployed the ideas of Marxist-media theorist Guy Debord (1931-1992). In his book Society of the Spectacle (1966), Debord delineates a society in which images replace the objective reality, and people are incapable of making real changes. The results of the current study show that despite their efforts, Nick and Amy, the two main characters of the novel, are no more than spectators with very little agency before the media. Moreover, following Debord’s argument about the replacement of reality with images, everyone and every institution in Gone Girl projects an image that does not necessarily embody the objective reality, a fact that makes it very hard to differentiate the real from unreal.

Keywords: agency, Debord, Gone Girl, media studies, society of spectacle, reality

Procedia PDF Downloads 93
119 Wave Propagation In Functionally Graded Lattice Structures Under Impact Loads

Authors: Mahmood Heshmati, Farhang Daneshmand

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Material scientists and engineers have introduced novel materials with complex geometries due to the recent technological advances and promotion of manufacturing methods. Among them, lattice structures with graded architectures denoted by functionally graded porous materials (FGPMs) have been developed to optimize the structural response. FGPMs are achieved by tailoring the size and density of the internal pores in one or more directions that lead to the desired mechanical properties and structural responses. Also, FGPMs provide more flexible transition and the possibility of designing and fabricating structural elements with complex and variable properties. In this paper, wave propagation in lattice structures with functionally graded (FG) porosity is investigated in order to examine the ability of shock absorbing effect. The behavior of FG porous beams with different porosity distributions under impact load and the effects of porosity distribution and porosity content on the wave speed are studied. Important conclusions are made, along with a discussion of the future scope of studies on FGPMs structures.

Keywords: functionally graded, porous materials, wave propagation, impact load, finite element

Procedia PDF Downloads 53
118 Islamic Banks and the Most Important Contemporary Challenges

Authors: Mahmood Mohammed Abdulsattar Aljumaili

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Praise be to Allah and peace and blessings be upon the Messenger of Allah. Islamic banks have not only made a lot of great achievements in a short period, but they imposed themselves in the global market, not to mention the transformation of some conventional interest-based banks to Islamic banks to the large demand on them, this transformation has pushed the Dow Jones Global Foundation to develop a new economic indicator released it (the Dow Jones Islamic market) for those who wish to invest in Islamic financial institutions. The success of Islamic financial institutions today face significant and serious challenges, that embody the serious consequences created by the current events on Islamic banking industry. This modest study, deals with these serious challenges facing the Islamic banking industry, and reflected on the success recorded in the previous period. The study deals with four main topics: The emergence of Islamic banks, the goals of Islamic banks, International challenges facing Islamic banks, internal challenges facing Islamic banks, and finally it touches on, (Basel 1-2) Agreement and its implications for Islamic banks.

Keywords: Islamic banks, Basel 1-2 agreement, most important contemporary challenges, islamic banking industry, Dow Jones Islamic market

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117 Involvement of BCRP/ABCG2 in Protective Mechanisms of Resveratrol against Methotrexate-Induced Renal Damage in Rats

Authors: Mohamed A. Morsy, Azza A. El-Sheikh, Abdulla Y. Al-Taher

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Resveratrol (RES) is a well-known polyphenol antioxidant. We have previously shown that testicular protective effect of RES against the anticancer drug methotrexate (MTX)-induced toxicity involves transporter-mediated mechanisms. Here, we investigated the effect of RES on MTX-induced nephrotoxicity. Rats were administered RES (10 mg/kg/day) for 8 days, with or without a single MTX dose (20 mg/kg i.p.) at day 4 of the experiment. MTX induced nephrotoxicity evident by significantly increase in serum blood urea nitrogen and creatinine compared to control, as well as distortion of kidney microscopic structure. MTX also significantly increased renal nitric oxide level, with induction of inducible nitric oxide synthase expression. MTX also significantly up-regulated fas ligand and caspase 3. Administering RES prior to MTX significantly improved kidney function and microscopic picture, as well as significantly decreased nitrosative and apoptotic markers compared to MTX alone. RES, but not MTX, caused significant increase in expression of breast cancer resistance protein (BCRP), an apical efflux renal transporter that participates in urinary elimination of both MTX and RES. Interestingly, concomitant MTX and RES caused further up-regulation of renal Bcrp compared to RES alone. Using Human BCRP ATPase assay, both RES and MTX exhibited dose-dependent increase in ATPase activity, with Km values of 0.52 ± 0.03 and 30.9 ± 4.2 µM, respectively. Furthermore, combined RES and MTX caused ATPase activity which was significantly less than maximum ATPase activity attained by the positive control; sulfasalazine (12.5 µM). In conclusion, RES exerted nephro-protection against MTX-induced toxicity through anti-nitrosative and anti-apoptotic effects, as well as via up-regulation of renal Bcrp.

Keywords: methotrexate, resveratrol, nephrotoxicity, breast cancer resistance protein

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116 Awareness, Use and Searching Behavior of 'Virtua' Online Public Access Catalog Users

Authors: Saira Soroya, Khalid Mahmood

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Library catalogs open the door to the library collection. OPAC (Online Public Access Catalog) are one of the services offered by automated libraries. The present study aims to explore user’s awareness, the level of use and their searching behavior of OPAC with a purpose to give suggestions and ways to improve user-friendly features of library OPAC. The population consisted of OPAC users of Lahore University of Management Sciences (LUMS). Convenient sampling technique was carried out. Total sample size was 100 OPAC users. Quantitative research design, based on survey method used to carry out the study. The data collection instrument was adopted. Data was analyzed using SPSS. Results revealed that a considerable number of users were not aware of OPAC i.e. (30%); however, those who were aware were using basic features of the OPAC. It was found that lack of knowledge was considered the frequent reason for not using all features of OPAC. In this regard, it is strongly recommended that compulsory information literacy programme should be established.

Keywords: catalog, OPAC, library automation, usability study, university library

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115 Bilateral Trade Costs Analysis of Policy Barriers for Growth Oriented Strategies in Exports

Authors: Shabana Noureen, Zafar Mahmood

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Economies consistently engage in trade across borders and face tariff, non-tariff barriers and other quotas that constitute trade costs. The trade costs imposed by policy barriers on exports are considered an impediment in the export growth rate. This work aims to measure over-year trends in total and bilateral trade costs and their trends in relevance to policy barriers (tariff and non-tariff). The analysis through the micro-founded theoretically based gravity model showed that the total trade costs have a general decreasing trend in the world while in the case of developing countries, the rate by which these trends decline is very low. Bilateral trade cost estimates associated with the policy barriers represent that the non-tariff barriers in a developing country have a major role in sustaining the high trade costs as compared to the tariff barriers. This ultimately leads to a low net declining rate. This work emphasizes that for developing countries the non-tariff barriers are a major factor that renders their exports and to be uncompetitive in the world market.

Keywords: trade costs, policy barriers, tariff barriers, non-tariff barriers, trade policies, export growth

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114 Pakistan’s Taxation System: A Critical Appraisal

Authors: Khalid Javed, Rashid Mahmood

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The constitution empowers the Federal Government to collect taxes on income other than agricultural income, taxes on capital value, customs, excise duties and sales taxes. The Central Board of Revenue (CBR) and its subordinate departments administer the tax system. Each of the three principal taxes has a different history and different set of issues. For a large number of income tax payers the core of the business process is pre-audit and assessment by a tax official. This process gives considerable discretion to tax officials, with potential for abuse. Moreover, this process is also not tenable as the number of taxpayers increase. The report is focused on a total overhaul of the process and organization of income tax. Sales tax is recent and its process and organization is adjusted to the needs of an expanding tax base. These are based on self-assessment and selective audit. Similarly, in customs the accent is on accelerating and broadening the changes begun in recent years. Before long, central excise will be subsumed in sales tax. During the nineties, despite many changes in the tax regime and introduction of withholding and presumptive taxes, Federal Government tax to GDP ratio has varied narrowly around eleven percent. The tax base has grown but still remains narrow and skewed. The number of income tax filers is around one million.

Keywords: central board of revenue, GDP, sale tax, income tax

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113 The Environment in Urban Planning and Management

Authors: Mahmood Salahi, Fatemeh Abbasi

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Increasing urbanization will be one of the defining features of the 21st century. This produces particular environmental challenges, but also creates opportunities for urban development that can contribute to broader goals of improving the quality of life for urban residents while achieving greater levels of global sustainability. Half of the world’s population already lives in urban areas, with a growing number of these people living in towns and cities in low and middle-income countries. As well as being a demographic phenomenon, urbanisation is intricately linked with economic, social and environmental transitions. The increasing proportion of the world’s population living in urban areas has been driven by the growing concentration of new investment and employment opportunities. In general, nations with the most rapid and sustained economic growth have urbanized most.2 Urban centres provide opportunities for a range of social and cultural activities, as well as being critical for innovations in science, technology and education. Indeed, urban areas are of critical importance for social and economic development: as the Cities Alliance recognizes, 'only sustained urban growth has the capacity to lift both rural and urban populations out of poverty'.

Keywords: environment, urban planning, management, urbanization

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112 Novel Oral Anticoagulants (NOACS) Adherence and Bleeding Events in Atrial Fibrillation Patients: A Systematic Review and Meta-Analysis

Authors: Tadesse Melaku Abegaz, Akshaya Srikanth Bahagavathula, Abdulla Shehab Sheab, Asim Hassen

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Objectives: Non-adherence and discontinuation of anticoagulant therapy lead to increased ischemic stroke risk and contributes to suboptimal outcomes of the anticoagulant treatment. This systematic review and meta-analysis were aimed to investigate the adherence to NOACs and adverse events in patients with AF. Methods: Original research articles conducted on patients with AF and using any NOACs (dabigatran, rivoraxaban and apixaban) reporting adherence for at least 35 days were included. Scientific databases including PubMed, Web of Science, and Google Scholar were searched using MeSH keywords to obtaining literature researched between 2008 to till June, 2016. Study characteristics, patient’s sociodemographic and clinical characteristics, medication adherence levels and bleeding events reported were recorded. Results: The overall sample size of the six studies is 1,640,157, with CHADS2 scores < 2 in 551 patients, CHADS2-VASc ≥ 2 in 62,232 AF patients. Three-forth [75.6% (95%CI= 66.5-84.8), p < 0.001] are adherent to NOACs. However, a higher rate [72.7% (62.5-82.9), p < 0.001] of adherence was observed with Dabigatran than Apixaban [59.9% (3.2-123.1), p=0.063] and Rivaroxaban [59.3% (38.7-80.0), p<0.001]. Sub-group analysis revealed that nearly 57% of the AF patients on NOACs have CHADS2 scores < 2 and 20% of these patients were non-adherent to NOACs. Overall bleeding events rate associated with NOACs non-adherent AF patients was found to be 7.5% (0.2-14.8), p=0.045. However, nearly 11.2% of AF patients experienced bleeding events were non-adherent to NOAC medications. A higher proportion of bleeding events were noticed with Dabigatran (14.7%). Conclusions: Adherence rates, while uniformly suboptimal, nevertheless varied considerably, lowest at 59.3% for rivaroxaban and 59.9% for apixaban, followed by dabigatran (75.6%). Overall bleeding events associated with NOACs rates were 7.5%. However, lower adherence to NOACs was associated with worse outcomes among patients with greater stroke risk.

Keywords: atrial fibrillation, bleeding events, meta-analysis, novel oral anticoagulants

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111 Enhancement in Seebeck Coefficient of MBE Grown Un-Doped ZnO by Thermal Annealing

Authors: M. Asghar, K. Mahmood, F. Malik, Lu Na, Y-H Xie, Yasin A. Raja, I. Ferguson

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In this paper, we have reported an enhancement in Seebeck coefficient of un-doped zinc oxide (ZnO) grown by molecular beam epitaxy (MBE) on silicon (001) substrate by annealing treatment. The grown ZnO thin films were annealed in oxygen environment at 500°C – 800°C, keeping a step of 100°C for one hour. Room temperature Seebeck measurements showed that Seebeck coefficient and power factor increased from 222 to 510 µV/K and 8.8×10^-6 to 2.6×10^-4 Wm^-1K^-2 as annealing temperature increased from 500°C to 800°C respectively. This is the highest value of Seebeck coefficient ever reported for un-doped MBE grown ZnO according to best of our knowledge. This observation was related with the improvement of crystal structure of grown films with annealing temperature. X-ray diffraction (XRD) results demonstrated that full width half maximum (FWHM) of ZnO (002) plane decreased and crystalline size increased as the annealing temperature increased. Photoluminescence study revealed that the intensity of band edge emission increased and defect emission decreased as annealing temperature increased because the density of oxygen vacancy related donor defects decreased with annealing temperature. This argument was further justified by the Hall measurements which showed a decreasing trend of carrier concentration with annealing temperature.

Keywords: ZnO, MBE, thermoelectric properties, annealing temperature, crystal structure

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110 Mutagenicity Evaluation of Locally Produced Biphasic Calcium Phosphate Using Ames Test

Authors: Nur Fathin Alia Che Wahab, Thirumulu Ponnuraj Kannan, Zuliani Mahmood, Ismail Ab. Rahman, Hanafi Ismail

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Locally produced Biphasic Calcium Phosphate (BCP) consists of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) which is a promising material for dentin and bone regeneration as well as in tissue engineering applications. The study was carried out to investigate the mutagenic effect of locally produced BCP using Ames test. Mutagenicity was evaluated with and without the addition of metabolic activation system (S9). This study was performed on Salmonella typhimurium TA98, TA102, TA1537, and TA1538 strains using preincubation assay method. The doses tested were 5000, 2500, 1250, 625, 313 µg/plate. Negative and positive controls were also included. The bacteria were incubated for 48 hours at 37 ± 0.5 °C. Then, the revertant colonies were counted. Data obtained were evaluated using non-statistical method. The mean number of revertant colonies in strains with and without S9 mix treated with locally produced BCP was less than double when compared to negative control for all the tested concentrations. The results from this study indicate that the locally produced BCP is non-mutagenic under the present test conditions.

Keywords: ames test, biphasic calcium phosphate, dentin regeneration, mutagenicity

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109 Modeling Dynamics and Control of Transversal Vibration of an Underactuated Flexible Plate Using Controlled Lagrangian Method

Authors: Mahmood Khalghollah, Mohammad Tavallaeinejad, Mohammad Eghtesad

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The method of Controlled Lagrangian is an energy shaping control technique for under actuated Lagrangian systems. Energy shaping control design methods are appealing as they retain the underlying nonlinear dynamics and can provide stability results that hold over larger domain than can be obtained using linear design and analysis. In the present study, controlled lagrangian is employed for designing a controller in an under actuated rotating flexible plate system. In the system of rotating flexible plate, due to its nonlinear characteristics and coupled dynamics of rigid and flexible components, controller design is a known challenge. In this paper, controller objectives are considered to be vibration reduction of flexible component and position control of the tip of the plate. To achieve the goals, a method based on both kinetic and potential energy shaping is introduced. The stability of the closed-loop system is investigated and proved around its equilibrium points. Moreover, the proposed controller is shown to be robust against disturbance and plant uncertainties.

Keywords: controlled lagrangian, underactuated system, flexible rotating plate, disturbance

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108 Molecular Dynamics Simulation of Free Vibration of Graphene Sheets

Authors: Seyyed Feisal Asbaghian Namin, Reza Pilafkan, Mahmood Kaffash Irzarahimi

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TThis paper considers vibration of single-layered graphene sheets using molecular dynamics (MD) and nonlocal elasticity theory. Based on the MD simulations, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS), an open source software, is used to obtain fundamental frequencies. On the other hand, governing equations are derived using nonlocal elasticity and first order shear deformation theory (FSDT) and solved using generalized differential quadrature method (GDQ). The small-scale effect is applied in governing equations of motion by nonlocal parameter. The effect of different side lengths, boundary conditions and nonlocal parameter are inspected for aforementioned methods. Results are obtained from MD simulations is compared with those of the nonlocal elasticity theory to calculate appropriate values for the nonlocal parameter. The nonlocal parameter value is suggested for graphene sheets with various boundary conditions. Furthermore, it is shown that the nonlocal elasticity approach using classical plate theory (CLPT) assumptions overestimates the natural frequencies.

Keywords: graphene sheets, molecular dynamics simulations, fundamental frequencies, nonlocal elasticity theory, nonlocal parameter

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107 A Survey on Early Screen Exposure during Infancy and Autism

Authors: I. Mahmood

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This survey was conducted to explore the hypothesis that excessive screen exposure combined with a subsequent decrease in parent-child interaction during infancy might be associated with autism. The main questions being asked are: Were children with autism exposed to long hours of screen time during the first 2 years of life? And what was the reason(s) for exposure at such an early age? Other variables were also addressed in this survey. An Arabic questionnaire was administered online (June 2019) via a Facebook page, relatively well-known in Arab countries. 1725 parents of children diagnosed with autism participated in this survey. Results show that 80.9% of children surveyed who were diagnosed with autism had been exposed to screens for long periods of time during the first 2 years of life. It can be inferred from the results of this survey that over-exposure to screens disrupt the parent-child interaction which is shown to be associated with ASD. The results of this survey highlight the harmful effects of screen exposure during infancy and the importance of parent-child interaction during the critical period of brain development. This paper attempts to further explore the connection between parent-child interaction and ASD, as well as serve as a call for further research and investigation of the relation between screens and parent-child interactions during infancy and Autism.

Keywords: attachment disorder, autism, screen exposure, virtual autism

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106 Framework for Implementation of National Electrical Safety Grounding Standards for Communication Infrastructure

Authors: Atif Mahmood, Mohammad Inayatullah Khan Babar

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Communication infrastructure has been installed, operated, and maintained all over the world according to defined electrical safety standards for separate or joint structures. These safety standards have been set for the safeguard of public, utility workers (employees and contractors), utility facilities, electrical communication equipment’s connected to the utility facilities and other facilities or premise adjacent to utility facilities. Different communication utilities in Pakistan use standards of different countries due to the absence of Common National Electrical Safety Standards of Pakistan. It is really important to devise a framework for implementation of a uniform standard for strict compliance. In this context, it is important to explore the compliance of safety standards for communication conductors and equipment for separate or joint structures for which NESC standards are taken as reference. Specific reference to grounding techniques including grounding AC/DC systems and its frames, leaving Fences, Messenger wires and special circuits used for the protection for lightning etc, ungrounded so recommendations are also given after in-depth analysis of current technical practices for the installation and maintenance of communication infrastructure.

Keywords: utility facilities, grounding electrodes, special circuits, grounding conductor

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105 Development of a Highly Flexible, Sensitive and Stretchable Polymer Nanocomposite for Strain Sensing

Authors: Shaghayegh Shajari, Mehdi Mahmoodi, Mahmood Rajabian, Uttandaraman Sundararaj, Les J. Sudak

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Although several strain sensors based on carbon nanotubes (CNTs) have been reported, the stretchability and sensitivity of these sensors have remained as a challenge. Highly stretchable and sensitive strain sensors are in great demand for human motion monitoring and human-machine interface. This paper reports the fabrication and characterization of a new type of strain sensors based on a stretchable fluoropolymer / CNT nanocomposite system made via melt-mixing technique. Electrical and mechanical characterizations were obtained. The results showed that this nanocomposite sensor has high stretchability up to 280% of strain at an optimum level of filler concentration. The piezoresistive properties and the strain sensing mechanism of the strain sensor were investigated using Electrochemical Impedance Spectroscopy (EIS). High sensitivity was obtained (gauge factor as large as 12000 under 120% applied strain) in particular at the concentrations above the percolation threshold. Due to the tunneling effect, a non- linear piezoresistivity was observed at high concentrations of CNT loading. The nanocomposites with good conductivity and lightweight could be a promising candidate for strain sensing applications.

Keywords: carbon nanotubes, fluoropolymer, piezoresistive, strain sensor

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104 Numerical Investigation on the Effect of Aluminium Nanoparticles on Characteristic Velocity of Kerosene-Oxygen Combustion

Authors: Al Ameen H., Rakesh P.

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To improve the combustion efficiency of fuels and to reduce the emissions of pollutants as well as to improve heat transfer characteristics of fuels, both non-metallic and metallic nanoparticles can be added into it. By varying the concentration and size of nano particles added into the fuels, behaviour of droplet combustion and hence heat generated can be altered. In case of solid or liquid fuels, surface area of the fuel in contact with oxidizer(gaseous) is small because of higher density compared to gases. If the surface area of fuel exposed to the oxidizer is very small, then the combustion will not occur, because the combustion rate is proportional to the surface area of fuel droplet. To avoid such instance there is a way to increase the exposed surface area. To increase the specific surface area available for reaction, the particle size can be reduced. If the additives are solid then by reducing the particles size the specific surface area of liquid fuel can be increased. For the liquid fuels the exposed surface area available for combustion can be increased by suspending nanoparticles. Addition of non-metallic and metallic nanoparticles in fuels improves its combustion efficiency by enhancing the thermo-physical properties. The burn rate constants and temperatures of Kerosene-Oxygen combustion for fuel droplet sizes of 50μm, 75μm, 100μm and 125μm under varying concentrations of 25%, 50%, 75% and 100% are studied numerically and its characteristic velocities are determined. Later the burn rate constants of fuel with concentrations of 0.5%, 1.0% and 2.0% by weight of aluminium nanoparticles are added. The spray combustion characteristics of such nano-fuel has improved the combustion temperature by the addition of aluminium nanoparticles. Thus, aluminium nanoparticles have improved burn rate and characteristic velocity of Kerosene-Oxygen combustion. An increase of 40% in characteristic velocity is observed.

Keywords: burn rate, characteristic velocity, combustion, thermo-physical properties

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103 Assessment of Radiological Dose for Th-232 Laboratory Accumulated in Tropical Freshwater Fish

Authors: Zal U’yun Wan Mahmood, Norfaizal Mohamed, Nita Salina Abu Bakar, Yii Mei Wo, Abdul Kadir Ishak, Mohamad Noh Sawon, Mohd Tarmizi Ishak, Khairul Nizam Razali

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The study of thorium radiotracer bioaccumulation in the whole body tropical freshwater fish (Anabas testudeneus; climb pearch) was performed. The objective of this study was to evaluate the effect of different Th-232 activity concentration andradiological dose in Anabas testudeneus under the laboratory bioaccumulation condition. Anabas testudeneus adults were exposed to different waterborne Th-232 levels: 0 BqL-1 (control), 50 BqL-1, 100 BqL-1,150 BqL-1and 200 BqL-1for 30 days. Radionuclide concentration ratios between the whole body levels and water levels were calculated and; total dose rates and risk quotients using ERICA Assessment Tool were also estimated. The results showed the increase of waterborne Th-232 concentration corresponded to a progressive decrease of Th concentration ratio. Meanwhile, the total dose rate (internal and external) in the whole body of Anabas testudeneus less than the ERICA dose rate screening value of 10 µGyh-1 and the risk quotient less than one. Thus, the findings can be concluded that the radiological dose of Th-232 to Anabas testudeneus is a very low probability and the situation may be considered to be of negligible radiological concern.

Keywords: Anabas testudeneus, bioaccumulation, radiological dose, Th-232

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102 Hydrogen Production at the Forecourt from Off-Peak Electricity and Its Role in Balancing the Grid

Authors: Abdulla Rahil, Rupert Gammon, Neil Brown

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The rapid growth of renewable energy sources and their integration into the grid have been motivated by the depletion of fossil fuels and environmental issues. Unfortunately, the grid is unable to cope with the predicted growth of renewable energy which would lead to its instability. To solve this problem, energy storage devices could be used. Electrolytic hydrogen production from an electrolyser is considered a promising option since it is a clean energy source (zero emissions). Choosing flexible operation of an electrolyser (producing hydrogen during the off-peak electricity period and stopping at other times) could bring about many benefits like reducing the cost of hydrogen and helping to balance the electric systems. This paper investigates the price of hydrogen during flexible operation compared with continuous operation, while serving the customer (hydrogen filling station) without interruption. The optimization algorithm is applied to investigate the hydrogen station in both cases (flexible and continuous operation). Three different scenarios are tested to see whether the off-peak electricity price could enhance the reduction of the hydrogen cost. These scenarios are: Standard tariff (1 tier system) during the day (assumed 12 p/kWh) while still satisfying the demand for hydrogen; using off-peak electricity at a lower price (assumed 5 p/kWh) and shutting down the electrolyser at other times; using lower price electricity at off-peak times and high price electricity at other times. This study looks at Derna city, which is located on the coast of the Mediterranean Sea (32° 46′ 0 N, 22° 38′ 0 E) with a high potential for wind resource. Hourly wind speed data which were collected over 24½ years from 1990 to 2014 were in addition to data on hourly radiation and hourly electricity demand collected over a one-year period, together with the petrol station data.

Keywords: hydrogen filling station off-peak electricity, renewable energy, off-peak electricity, electrolytic hydrogen

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101 Taleghan Dam Break Numerical Modeling

Authors: Hamid Goharnejad, Milad Sadeghpoor Moalem, Mahmood Zakeri Niri, Leili Sadeghi Khalegh Abadi

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While there are many benefits to using reservoir dams, their break leads to destructive effects. From the viewpoint of International Committee of Large Dams (ICOLD), dam break means the collapse of whole or some parts of a dam; thereby the dam will be unable to hold water. Therefore, studying dam break phenomenon and prediction of its behavior and effects reduces losses and damages of the mentioned phenomenon. One of the most common types of reservoir dams is embankment dam. Overtopping in embankment dams occurs because of flood discharge system inability in release inflows to reservoir. One of the most important issues among managers and engineers to evaluate the performance of the reservoir dam rim when sliding into the storage, creating waves is large and long. In this study, the effects of floods which caused the overtopping of the dam have been investigated. It was assumed that spillway is unable to release the inflow. To determine outflow hydrograph resulting from dam break, numerical model using Flow-3D software and empirical equations was used. Results of numerical models and their comparison with empirical equations show that numerical model and empirical equations can be used to study the flood resulting from dam break.

Keywords: embankment dam break, empirical equations, Taleghan dam, Flow-3D numerical model

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100 Model Based Fault Diagnostic Approach for Limit Switches

Authors: Zafar Mahmood, Surayya Naz, Nazir Shah Khattak

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The degree of freedom relates to our capability to observe or model the energy paths within the system. Higher the number of energy paths being modeled leaves to us a higher degree of freedom, but increasing the time and modeling complexity rendering it useless for today’s world’s need for minimum time to market. Since the number of residuals that can be uniquely isolated are dependent on the number of independent outputs of the system, increasing the number of sensors required. The examples of discrete position sensors that may be used to form an array include limit switches, Hall effect sensors, optical sensors, magnetic sensors, etc. Their mechanical design can usually be tailored to fit in the transitional path of an STME in a variety of mechanical configurations. The case studies into multi-sensor system were carried out and actual data from sensors is used to test this generic framework. It is being investigated, how the proper modeling of limit switches as timing sensors, could lead to unified and neutral residual space while keeping the implementation cost reasonably low.

Keywords: low-cost limit sensors, fault diagnostics, Single Throw Mechanical Equipment (STME), parameter estimation, parity-space

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99 Determination the Effects of Physico-Chemical Parameters on Groundwater Status by Water Quality Index

Authors: Samaneh Abolli, Mahdi Ahmadi Nasab, Kamyar Yaghmaeian, Mahmood Alimohammadi

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The quality of drinking water, in addition to the presence of physicochemical parameters, depends on the type and geographical location of water sources. In this study, groundwater quality was investigated by sampling total dissolved solids (TDS), electrical conductivity (EC), total hardness (TH), Cl, Ca²⁺, and Mg²⁺ parameters in 13 sites, and 40 water samples were sent to the laboratory. Electrometric, titration, and spectrophotometer methods were used. In the next step, the water quality index (WQI) was used to investigate the impact and weight of each parameter in the groundwater. The results showed that only the mean of magnesium ion (40.88 mg/l) was lower than the guidelines of World Health Organization (WHO). Interpreting the WQI based on the WHO guidelines showed that the statuses of 21, 11, and 7 samples were very poor, poor, and average quality, respectively, and one sample had excellent quality. Among the studied parameters, the means of EC (2,087.49 mS/cm) and Cl (1,015.87 mg/l) exceeded the global and national limits. Classifying water quality of TH was very hard (87.5%), hard (7.5%), and moderate (5%), respectively. Based on the geographical distribution, the drinking water index in sites 4 and 11 did not have acceptable quality. Chloride ion was identified as the responsible pollutant and the most important ion for raising the index. The outputs of statistical tests and Spearman correlation had significant and direct correlation (p < 0.05, r > 0.7) between TDS, EC, and chloride, EC and chloride, as well as TH, Ca²⁺, and Mg²⁺.

Keywords: water quality index, groundwater, chloride, GIS, Garmsar

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98 Comparative Acaricidal Efficacy of Fluralaner vs Oral Ivermectin Against Tick Infestation in Dogs

Authors: Tayyaba Zahra, Shehla Gul Bokhari, Asim Khalid Mahmood, Raheela Akhtar, Khizar Matloob

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In Pakistan, dogs are commonly infested with ticks, especially in summers, causing not only dermatological issues but also systemic problems. Persistence of tick infestation often leads to heavy losses. Different acaricides are locally available with variable efficacy; however, recurrence of infestation is commonly reported. The present study was thus designed to compare the efficacy of a novel drug Fluralaner and conventionally used Ivermectin against tick infestation. Dogs positive for tick infestation were randomly divided into 2 groups viz, Groups A and B having 8 dogs each. Ticks were enumerated manually from the whole body of dogs at day 0 before the administration of drugs Dogs in Group A were treated with Fluralaner at day 0, and dogs in Group B were treated with Ivermectin. Post-treatment, ticks were counted again at days 7, 14, 21, 28, and 35. At day 07 of the study, no tick was found on the dogs treated with Fluralaner, while many ticks were present on the dogs treated with Ivermectin showing an efficacy up to 50%. On the consecutive follow-up evaluations, similar results were found for Fluralaner while the efficacy of Ivermectin was further reduced to less than 50%. Furthermore, Fluralaner treated dogs had better RBC counts, PCV, Hgb concentration, LFTs, RFTs post-treatment than the dogs treated with Ivermectin. Statistically, oral Fluralaner proved a more effective drug (P≤0.05)than oral Ivermectin against tick infestation in dogs.

Keywords: fluralaner, ivermectin, dogs, tick infestations

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97 Experimental and Analytical Study of Various Types of Shear Connector Used for Cold-Formed Steel-Ferrocement Composite Beam

Authors: Talal Alhajri, Mahmood M. Tahir, Khaled Alenezi, Mohamad Ragaee

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This work presents the experimental tests carried out to evaluate the behaviour of different types of shear connectors proposed for cold formed steel (CFS) section integrated with ferrocement slab as potential used for composite beam. Ten push-out test specimens of cold-formed steel lipped channel sections connected with ferrocement slab were tested. Three types of shear connectors were studied comprised of bolts, self-drilling-screw and bar angle. The connection behavior is analysed in terms of its load-slip relationship and the failure mode. The parametric studies were performed to investigate the effect on the shear connector’s capacity by varying the number of layers of wire mesh used in ferrocement slab and types of shear connector used. An analytical analysis using ANSYS program and theoretical analysis (Eurocode 4) were carried out to verify the experiment results. The results show that the experimental, theoretical, and numerical values proved to have good agreement with each other.

Keywords: cold-formed steel, composite beam, ferrocement, finite element method, push-out test, shear connector

Procedia PDF Downloads 338
96 Comparison of Applicability of Time Series Forecasting Models VAR, ARCH and ARMA in Management Science: Study Based on Empirical Analysis of Time Series Techniques

Authors: Muhammad Tariq, Hammad Tahir, Fawwad Mahmood Butt

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Purpose: This study attempts to examine the best forecasting methodologies in the time series. The time series forecasting models such as VAR, ARCH and the ARMA are considered for the analysis. Methodology: The Bench Marks or the parameters such as Adjusted R square, F-stats, Durban Watson, and Direction of the roots have been critically and empirically analyzed. The empirical analysis consists of time series data of Consumer Price Index and Closing Stock Price. Findings: The results show that the VAR model performed better in comparison to other models. Both the reliability and significance of VAR model is highly appreciable. In contrary to it, the ARCH model showed very poor results for forecasting. However, the results of ARMA model appeared double standards i.e. the AR roots showed that model is stationary and that of MA roots showed that the model is invertible. Therefore, the forecasting would remain doubtful if it made on the bases of ARMA model. It has been concluded that VAR model provides best forecasting results. Practical Implications: This paper provides empirical evidences for the application of time series forecasting model. This paper therefore provides the base for the application of best time series forecasting model.

Keywords: forecasting, time series, auto regression, ARCH, ARMA

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95 Understanding Walkability in the Libyan Urban Space: Policies, Perceptions and Smart Design for Sustainable Tripoli

Authors: A. Abdulla Khairi Mohamed, Mohamed Gamal Abdelmonem, Gehan Selim

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Walkability in civic and public spaces in Libyan cities is challenging due to the lack of accessibility design, informal merging into car traffic, and the general absence of adequate urban and space planning. The lack of accessible and pedestrian-friendly public spaces in Libyan cities has emerged as a major concern for the government if it is to develop smart and sustainable spaces for the 21st century. A walkable urban space has become a driver for urban development and redistribution of land use to ensure pedestrian and walkable routes between sites of living and workplaces. The characteristics of urban open space in the city centre play a main role in attracting people to walk when attending their daily needs, recreation and daily sports. There is significant gap in the understanding of perceptions, feasibility and capabilities of Libyan urban space to accommodate enhance or support the smart design of a walkable pedestrian-friendly environment that is safe and accessible to everyone. The paper aims to undertake observations of walkability and walkable space in the city of Tripoli as a benchmark for Libyan cities; assess the validity and consistency of the seven principal aspects of smart design, safety, accessibility and 51 factors that affect the walkability in open urban space in Tripoli, through the analysis of 10 local urban spaces experts (town planner, architect, transport engineer and urban designer); and explore user groups’ perceptions of accessibility in walkable spaces in Libyan cities through questionnaires. The study sampled 200 respondents in 2015-16. The results of this study are useful for urban planning, to classify the walkable urban space elements which affect to improve the level of walkability in the Libyan cities and create sustainable and liveable urban spaces.

Keywords: walkability, sustainability, liveability, accessibility

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94 Powder Flow with Normalized Powder Particles Size Distribution and Temperature Analyses in Laser Melting Deposition: Analytical Modelling and Experimental Validation

Authors: Muhammad Arif Mahmood, Andrei C. Popescu, Mihai Oane, Diana Chioibascu, Carmen Ristoscu, Ion N. Mihailescu

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Powder flow and temperature distributions are recognized as influencing factors during laser melting deposition (LMD) process, that not only affect the consolidation rate but also characteristics of the deposited layers. Herewith, two simplified analytical models will be presented to simulate the powder flow with the inclusion of powder particles size distribution in Gaussian form, under three powder jet nozzles, and temperature analyses during LMD process. The output of the 1st model will serve as the input in the 2nd model. The models will be validated with experimental data, i.e., weight measurement method for powder particles distribution and infrared imaging for temperature analyses. This study will increase the cost-efficiency of the LMD process by adjustment of the operating parameters for reaching optimal powder debit and energy. This research has received funds under the Marie Sklodowska-Curie grant agreement No. 764935, from the European Union’s Horizon 2020 research and innovation program.

Keywords: laser additive manufacturing, powder particles size distribution in Gaussian form, powder stream distribution, temperature analyses

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93 Burnishing of Aluminum-Magnesium-Graphite Composites

Authors: Mohammed T. Hayajneh, Adel Mahmood Hassan, Moath AL-Qudah

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Burnishing is increasingly used as a finishing operation to improve surface roughness and surface hardness. This can be achieved by applying a hard ball or roller onto metallic surfaces under pressure, in order to achieve many advantages in the metallic surface. In the present work, the feed rate, speed and force have been considered as the basic burnishing parameters to study the surface roughness and surface hardness of metallic matrix composites. The considered metal matrix composites were made from Aluminum-Magnesium-Graphite with five different weight percentage of graphite. Both effects of burnishing parameters mentioned above and the graphite percentage on the surface hardness and surface roughness of the metallic matrix composites were studied. The results of this investigation showed that the surface hardness of the metallic composites increases with the increase of the burnishing force and decreases with the increase in the burnishing feed rate and burnishing speed. The surface roughness of the metallic composites decreases with the increasing of the burnishing force, feed rate, and speed to certain values, then it starts to increase. On the other hand, the increase in the weight percentage of the graphite in the considered composites causes a decrease in the surface hardness and an increase in the surface roughness.

Keywords: burnishing process, Al-Mg-Graphite composites, surface hardness, surface roughness

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92 Biogeochemical Study of Polycuclic Aromatic Hydrocarbons and Its Physiological Response in Mudskippre (B. dussumieri) along the North western Coasts of the Persian Gulf

Authors: Ali Mashinchian Moradi, Mahmood Sinaei

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Study on the biomarkers to assess health status of marine ecosystems has an important value in biomonitoring of marine environment. Accordingly, accumulation of polycyclic aromatic hydrocarbons in sediment, water and tissues (liver and gill) of mudskipper (Boleophthalmus dussmieri) and some physiological responses like lysosomal membrane change in haemocytes and the Glutathione-S Transferase (GST) activity in the liver were measured in mudskippers. Samples were collected from five sites along the noth western cost of the Persian Gulf. PAHs concentration was measured by HPLC method. The activity of GST enzyme was analysed by spectrophotometric method. Total PAH concentration in coastal seawater, sediments, liver and gill tissues ranged between 0.80-18.34 ug/L, 113.550-3384.34 ng/g dw, 3.99-46.64 ng/g dw and 3.11-17.This study showed that PAH concentrations in this region are not higher than available standards. The findings revile that lysosomal membrane destabilization and liver GST activities are highly sensitive to PAHs in mudskipper, B. dussumieri. Sediment PAH concentrations were strongly correlated with biomarkers, indicating PAHs were biologically available to fish. Thus, mudskipper perceived to be good sentinel organism for PAH pollution biomonitoring.

Keywords: PAHs, biomarker, mudskipper, Persian Gulf

Procedia PDF Downloads 324