Search results for: Mohamad Reza Niknam
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 720

Search results for: Mohamad Reza Niknam

510 Management of Religious Endowment Properties for Sustainable Development: A Case Study of Region of Kinniya, Sri Lanka

Authors: Muhammed Buhary Muhammed Thabith, Nor Asiah Mohamad

Abstract:

Religious Endowment (RE) (Waqf) has played an essential role in Islamic history and made a significant impact on the society, particularly in terms of socioeconomics. This has been made possible by having appropriate management of the RE propertiesin order to achieve the Sustainable Development Goals (SDGs), and the region of Kinniya, Sri Lanka, is not an exception. However, since the last Religious Endowment Act of 1982, a considerable deterioration has taken place, and cases of dormant properties have increased. This study proposes a conceptual model based on the SDGs initiatives to fill in the gaps. It analyses the application of the current RE properties management and identifies the issues as well as the challenges in the implementation of the RE Act. It adopts a doctrinal analysis involving the primary and secondary data, including statutes, practices, case law, and reports. The findings show that there are various management modes adopted by the stakeholders of RE. Some approaches are in tandem with the rules and practices of the SDGs with emphasis on support and cooperation from the community, private sector, and the government. Several initiatives such as awareness on RE, legal enforcements without fears and favours, as well as accounting and auditing, are recommended to minimize problems in managing the RE towards attaining the SDGs.

Keywords: sustainable development goals (SDGs), management, endowment, Sri Lanka

Procedia PDF Downloads 65
509 Random Subspace Ensemble of CMAC Classifiers

Authors: Somaiyeh Dehghan, Mohammad Reza Kheirkhahan Haghighi

Abstract:

The rapid growth of domains that have data with a large number of features, while the number of samples is limited has caused difficulty in constructing strong classifiers. To reduce the dimensionality of the feature space becomes an essential step in classification task. Random subspace method (or attribute bagging) is an ensemble classifier that consists of several classifiers that each base learner in ensemble has subset of features. In the present paper, we introduce Random Subspace Ensemble of CMAC neural network (RSE-CMAC), each of which has training with subset of features. Then we use this model for classification task. For evaluation performance of our model, we compare it with bagging algorithm on 36 UCI datasets. The results reveal that the new model has better performance.

Keywords: classification, random subspace, ensemble, CMAC neural network

Procedia PDF Downloads 297
508 Study of Nanocrystalline Scintillator for Alpha Particles Detection

Authors: Azadeh Farzaneh, Mohammad Reza Abdi, A. Quaranta, Matteo Dalla Palma, Seyedshahram Mortazavi

Abstract:

We report on the synthesis of cesium-iodide nanoparticles using sol-gel technique. The structural properties of CsI nanoparticles were characterized by X-ray diffraction and Scanning Electron Microscope (SEM) Also, optical properties were followed by optical absorption and UV–vis fluorescence. Intense photoluminescence is also observed, with some spectral tuning possible with ripening time getting a range of emission photon wavelength approximately from 366 to 350 nm. The size effect on CsI luminescence leads to an increase in scintillation light yield, a redshift of the emission bands of the on_center and off_center self_trapped excitons (STEs) and an increase in the contribution of the off_center STEs to the net intrinsic emission yield. The energy transfer from the matrix to CsI nanoparticles is a key characteristic for scintillation detectors. So the scintillation spectra to alpha particles of sample were monitored.

Keywords: nanoparticles, luminescence, sol gel, scintillator

Procedia PDF Downloads 561
507 Natural Interaction Game-Based Learning of Elasticity with Kinect

Authors: Maryam Savari, Mohamad Nizam Ayub, Ainuddin Wahid Abdul Wahab

Abstract:

Game-based Learning (GBL) is an alternative that provides learners with an opportunity to experience a volatile environment in a safe and secure place. A volatile environment requires a different technique to facilitate learning and prevent injury and other hazards. Subjects involving elasticity are always considered hazardous and can cause injuries,for instance a bouncing ball. Elasticity is a topic that necessitates hands-on practicality for learners to experience the effects of elastic objects. In this paper the scope is to investigate the natural interaction between learners and elastic objects in a safe environment using GBL. During interaction, the potentials of natural contact in the process of learning were explored and gestures exhibited during the learning process were identified. GBL was developed using Kinect technology to teach elasticity to primary school children aged 7 to 12. The system detects body gestures and defines the meanings of motions exhibited during the learning process. The qualitative approach was deployed to constantly monitor the interaction between the student and the system. Based on the results, it was found that Natural Interaction GBL (Ni-GBL) is engaging for students to learn, making their learning experience more active and joyful.

Keywords: elasticity, Game-Based Learning (GBL), kinect technology, natural interaction

Procedia PDF Downloads 449
506 Reliability Assessment of Various Empirical Formulas for Prediction of Scour Hole Depth (Plunge Pool) Using a Comprehensive Physical Model

Authors: Majid Galoie, Khodadad Safavi, Abdolreza Karami Nejad, Reza Roshan

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In this study, a comprehensive scouring model has been developed in order to evaluate the accuracy of various empirical relationships which were suggested for prediction of scour hole depth in plunge pools by Martins, Mason, Chian and Veronese. For this reason, scour hole depths caused by free falling jets from a flip bucket to a plunge pool were investigated. In this study various discharges, angles, scouring times, etc. have been considered. The final results demonstrated that the all mentioned empirical formulas, except Mason formula, were reasonably agreement with the experimental data.

Keywords: scour hole depth, plunge pool, physical model, reliability assessment

Procedia PDF Downloads 496
505 The Evaluation of Signal Timing Optimization and Implement of Transit Signal Priority in Intersections and Their Effect on Delay Reduction

Authors: Mohammad Reza Ramezani, Shahriyar Afandizadeh

Abstract:

Since the intersections play a crucial role in traffic delay, it is significant to evaluate them precisely. In this paper, three critical intersections in Tehran (Capital of Iran) had been simulated. The main purpose of this paper was to optimize the public transit delay. The simulation had three different phase in three intersections of Tehran. The first phase was about the current condition of intersection; the second phase was about optimized signal timing and the last phase was about prioritized public transit access. The Aimsun software was used to simulate all phases, and the Synchro software was used to optimization of signals as well. The result showed that the implement of optimization and prioritizing system would reduce about 50% of delay for public transit.

Keywords: transit signal priority, intersection optimization, public transit, simulation

Procedia PDF Downloads 435
504 Sandwich Structure Composites: Effect of Kenaf on Mechanical Properties

Authors: Maizatulnisa Othman, Mohamad Bukhari, Zahurin Halim, Souad A. Muhammad, Khalisani Khalid

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Sandwich structure composites produced by epoxy core and aluminium skin were developed as potential building materials. Interface bonding between core and skin was controlled by varying kenaf content. Five different weight percentage of kenaf loading ranging from 10 wt% to 50 wt% were employed in the core manufacturing in order to study the mechanical properties of the sandwich composite. Properties of skin aluminium with epoxy were found to be affected by drying time of the adhesive. Mechanical behavior of manufactured sandwich composites in relation with properties of constituent materials was studied. It was found that 30 wt% of kenaf loading contributed to increase the flexural strength and flexural modulus up to 102 MPa and 32 Gpa, respectively. Analysis were done on the flatwise and edgewise compression test. For flatwise test, it was found that 30 wt% of fiber loading could withstand maximum force until 250 kN, with compressive strength results at 96.94 MPa. However, at edgewise compression test, the sandwich composite with same fiber loading only can withstand 31 kN of the maximum load with 62 MPa of compressive strength results.

Keywords: sandwich structure composite, epoxy, aluminium, kenaf fiber

Procedia PDF Downloads 358
503 Analysis of the Effect of Food Veils on the Preservation of Button and Oyster Mushrooms, Case Study: Zein Corn Coating

Authors: Mohamad Javad Shakouri, Hamid Tavakkolipour, Mahdis Jamshidi Tehranian

Abstract:

The inclination toward using food coatings is increasing daily, due to containing natural elements and not producing environmental pollution. Food coatings are uniform and thin layers of natural substances that cover the food product and act as a barrier against moisture, oxygen, and substances dissolved in food. Using food coatings on fruits and vegetables can delay water dissipation, losing aroma, decolorization, and improve the appearance of the product, and in general, preserve and protect the quality of fresh produce. When fruits and vegetables grow, they are equipped with a natural shield, called cuticle– a layer of wax. Washing the products, after harvest, the cuticle – this protective coating – is removed. In order to replace the cuticle, we can use an edible protective coating. This coating delays dehydration and deterioration and hence increases the life of the product while keeping its moisture. In this study, it was concluded that using food coatings, such as corn zein, carrageenan, and starch can have a substantial effect on the quantitative and qualitative preservation of food products, such as fruits, vegetables, and mushrooms.

Keywords: food coating, corn zein, button and oyster mushrooms, ascorbic and citric acids

Procedia PDF Downloads 264
502 Students' Perceptions and Gender Relationships towards the Mobile Learning in Polytechnic Mukah Sarawak (Malaysia)

Authors: Habsah Mohamad Sabli, Mohammad Fardillah Wahi

Abstract:

The main aim of this research study is to better understand and measure students' perceptions towards the effectiveness of mobile learning. This paper reports on the results of a survey of three hundred nineteen students at Polytechnic Mukah Sarawak (PMU) about their perception to the use of mobile technology in education. An analysis of the quantitative survey findings is presented focusing on the ramification for mobile-learning (m-learning) practices in higher learning and teaching environments. In this paper we present our research findings about the level of perception and gender correlations with perceived ease of use and perceived usefulness using M-Learning in learning activities among students in Polytechnic Mukah (PMU). Based on gender respondent, were 150 female (47.0%) and 169 male (53.0%). The survey findings further revealed that perception of students are in moderately high and agree for using m-learning. The perceived ease of use and perceived usefulness is significant with weak correlations between students to adapt m-learning for active learning activities. The outcome of this research can benefit the decision makers of higher institution in Mukah Sarawak regard to way to enhance m-learning and promote effective teaching and learning activities as well as strengthening the quality of learning delivery.

Keywords: M-learning, student attitudes, student perception, mobile technology

Procedia PDF Downloads 467
501 Finding the Free Stream Velocity Using Flow Generated Sound

Authors: Saeed Hosseini, Ali Reza Tahavvor

Abstract:

Sound processing is one the subjects that newly attracts a lot of researchers. It is efficient and usually less expensive than other methods. In this paper the flow generated sound is used to estimate the flow speed of free flows. Many sound samples are gathered. After analyzing the data, a parameter named wave power is chosen. For all samples, the wave power is calculated and averaged for each flow speed. A curve is fitted to the averaged data and a correlation between the wave power and flow speed is founded. Test data are used to validate the method and errors for all test data were under 10 percent. The speed of the flow can be estimated by calculating the wave power of the flow generated sound and using the proposed correlation.

Keywords: the flow generated sound, free stream, sound processing, speed, wave power

Procedia PDF Downloads 358
500 End-of-Life Vehicle Framework in Bumper Development Process

Authors: Majid Davoodi Makinejad, Reza Ghaeli

Abstract:

Developing sustainable and environment-friendly products has become a major concern in the car manufacturing industry. New legislation ‘End of Life Vehicle’ increased design complexities of bumper system parameters e.g. design for disassembly, design for remanufacturing and recycling. ELV processing employs dismantling, shredding and landfill. The bumper is designed to prevent physical damage, reduce aerodynamic drag force as well as being aesthetically pleasing to the consumer. Design for dismantling is the first step in ELVs approach in the bumper system. This study focused on the analysis of ELV value in redesign solutions of the bumper system in comparison with the conventional concept. It provided a guideline to address the critical consideration in material, manufacturing and joining methods of bumper components to take advantages in easy dismounting, separation and recycling.

Keywords: sustainable development, environmental friendly, bumper system, end of life vehicle

Procedia PDF Downloads 349
499 Uncovering the Relationship between EFL Students' Self-Concept and Their Willingness to Communicate in Language Classes

Authors: Seyedeh Khadijeh Amirian, Seyed Mohammad Reza Amirian, Narges Hekmati

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The current study aims at examining the relationship between English as a foreign language (EFL) students' self-concept and their willingness to communicate (WTC) in EFL classes. To this effect, two questionnaires, namely 'Willingness to Communicate' (MacIntyre et al., 2001) and 'Self-Concept Scale' (Liu and Wang, 2005), were distributed among 174 (45 males and 129 females) Iranian EFL university students. Correlation and regression analyses were conducted to examine the relationship between the two variables. The results indicated that there was a significantly positive correlation between EFL students' self-concept and their WTC in EFL classes (p < .0.05). Moreover, regression analyses indicated that self-concept has a significantly positive influence on students’ WTC in language classes (B= .302, p < .0.05) and explains .302 percent of the variance in the dependent variable (WTC). The results are discussed with regards to the individual differences in educational contexts, and implications are offered.

Keywords: EFL students, language classes, willingness to communicate, self-concept

Procedia PDF Downloads 94
498 Assessment of Breast, Lung and Liver Effective Doses in Heart Imaging by CT-Scan 128 Dual Sources with Use of TLD-100 in RANDO Phantom

Authors: Seyedeh Sepideh Amini, Navideh Aghaei Amirkhizi, Seyedeh Paniz Amini, Seyed Soheil Sayyahi, Mohammad Reza Davar Panah

Abstract:

CT-Scan is one of the lateral and sectional imaging methods that produce 3D-images with use of rotational x-ray tube around central axis. This study is about evaluation and calculation of effective doses around heart organs such as breast, lung and liver with CT-Scan 128 dual sources with TLD_100 and RANDO Phantom by spiral, flash and conventional protocols. In results, it is showed that in spiral protocol organs have maximum effective dose and minimum in flash protocol. Thus flash protocol advised for children and risk persons.

Keywords: X-ray computed tomography, dosimetry, TLD-100, RANDO, phantom

Procedia PDF Downloads 442
497 Eu³⁺ PVC Membrane Sensor Based on 1,2-Diaminopropane-N,N,N',N'-Tetraacetic Acid

Authors: Noshin Mehrabian, Mohammad Reza Abedi, Hassan Ali Zamani

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A highly selective poly(vinyl chloride)-based membrane sensor produced by using 1,2-Diaminopropane-N,N,N',N'-tetraacetic acid (DAPTA) as active material is described. The electrode displays Nernstian behavior over the concentration range 1.0×10⁻⁶ to 1.0×10⁻² M. The detection limit of the electrode is 7.2×10⁻⁷ M. The best performance was obtained with the membrane containing 30% polyvinyl chloride (PVC), 65% nitrobenzene (NB), 2% sodium tetra phenyl borate (Na TPB), 3% DAPTA. The potentiometric response of the proposed electrode is pH independent in the range of 2.5–‎‎9.1. ‎The proposed sensor displays a fast response time 'less than 10s'. The electrode shows a good selectivity for Eu (III) ion with respect to most common cations including alkali, alkaline earth, transition, and heavy metal ions. It was used as an indicator electrode in potentiometric ‎titration of 25 mL of a 1.0×10⁻⁴ M Eu (III) solution with a 1.0×10⁻² M EDTA solution.

Keywords: potentiometry, PVC membrane, sensor, ion-selective electrode

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496 Using Cooperation Approaches at Different Levels of Artificial Bee Colony Method

Authors: Vahid Zeighami, Mohsen Ghsemi, Reza Akbari

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In this work, a Multi-Level Artificial Bee Colony (called MLABC) is presented. In MLABC two species are used. The first species employs n colonies in which each of the them optimizes the complete solution vector. The cooperation between these colonies is carried out by exchanging information through a leader colony, which contains a set of elite bees. The second species uses a cooperative approach in which the complete solution vector is divided to k sub-vectors, and each of these sub-vectors is optimized by a a colony. The cooperation between these colonies is carried out by compiling sub-vectors into the complete solution vector. Finally, the cooperation between two species is obtained by exchanging information between them. The proposed algorithm is tested on a set of well known test functions. The results show that MLABC algorithms provide efficiency and robustness to solve numerical functions.

Keywords: artificial bee colony, cooperative, multilevel cooperation, vector

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495 Radiation Effect on MHD Casson Fluid Flow over a Power-Law Stretching Sheet with Chemical Reaction

Authors: Motahar Reza, Rajni Chahal, Neha Sharma

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This article addresses the boundary layer flow and heat transfer of Casson fluid over a nonlinearly permeable stretching surface with chemical reaction in the presence of variable magnetic field. The effect of thermal radiation is considered to control the rate of heat transfer at the surface. Using similarity transformations, the governing partial differential equations of this problem are reduced into a set of non-linear ordinary differential equations which are solved by finite difference method. It is observed that the velocity at fixed point decreases with increasing the nonlinear stretching parameter but the temperature increases with nonlinear stretching parameter.

Keywords: boundary layer flow, nonlinear stretching, Casson fluid, heat transfer, radiation

Procedia PDF Downloads 367
494 Pregnancy through the Lens of Iranian Women with HIV: A Qualitative

Authors: Zahra BehboodiI-Moghadam, Zohre Khalajinia, Ali Reza Nikbakht Nasrabadi, Minoo Mohraz

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The purpose of our study was to explore and describe the experiences of pregnant women with HIV in Iran. A qualitative exploratory study with conventional content analysis was used. Twelve pregnant women with HIV who referred to perinatal care at the Imam Khomeini Hospital Behavioral Diseases Consultation: Center in Tehran were recruited to participate in in-depth interviews. The average age of the participants was 32.5 years. Four main themes were extracted from the data: “fear and hope, “stigma and discrimination, “marital life stability” and “trust”. The findings reveal the pregnant women living with HIV are vulnerable and need professional support. Improving the knowledge of healthcare professionals especially midwifes on pregnancy complications for women with HIV is crucial in order to provide high-quality care to pregnant women with HIV-positive.

Keywords: HIV, pregnancy, content analysis, experiences, Iran, qualitative research

Procedia PDF Downloads 438
493 Comparative Study of Serum Lipid Profile of Obese and Non-Obese Students of Al-Jouf University

Authors: Mohammad Najmuddin Khan, Mohamad Khaleel Albalwi

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The prevalence of obesity has risen dramatically in past several decades. Hormonal and genetic factors are rarely the cause of childhood obesity. Because obese adult may suffer life-long physical and emotional consequences, it is imperative to discuss prevention with parents during well-child examinations. Purpose of the study was to compare the serum lipid profile of obese and non-obese males. Twenty two male students were selected from Al-Jouf University. Their age ranged from 19 to 29. They were divided into groups. One group (N=15) having more than 20% fat was considered as obese group, another group (N=7) was considered as non-obese group. Fasting blood samples were analysed for blood cholesterol, triglycerides, low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C). Independent test was applied to compare mean difference. In obese group, significantly higher cholesterol and triglycerides were observed. On the contrary, obese group had significantly lower HDL-C concentration than the non-obese group. The adult obese has relatively larger changes in serum lipids at any given level of obesity. On the average, higher amount of fat makes it more likely for an individual to be dyslipidemic and to express elements of the metabolic syndrome. Increased triglycerides level in obese impaired lipolysis which reduced the HDL-C concentrations.

Keywords: obesity, serum lipid profile, Al-Jouf, HDL, LDL

Procedia PDF Downloads 249
492 Comparison of Particle Size for ɑ(Alpha) Fe2O3 and ɤ(Gamma)Fe2O3 on Heat Transfer Performance in an Copper Oscillating Heat Pipe

Authors: Hamid Reza Goshayeshi

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The effect of ɑ(alpha) Fe2O3 and ɤ(gamma)Fe2O3 particles on the heat transfer performance of an oscillating heat pipe was investigated experimentally. Kerosene was used as the base fluid for the OHP. Six size particles with average diameters of 10 nm, 20 nm, and 30 nm ɑFe2O3 and ɤFe2O3 were investigated, respectively. Experimental results show that the ɤFe2O3 particles added in the OHP significantly affect the heat transfer performance. When the OHP was charged with kerosene and 20 nm ɤ Fe2O3 particles, the OHP can achieve the best heat transfer performance among six particles investigated in this research.

Keywords: copper oscillating heat pipe, heat transfer, flow, comparison of ɑ(alpha)Fe2O3 and ɤ(gamma)Fe2O3, increase heat transfer

Procedia PDF Downloads 280
491 Numerical Simulation and Experimental Validation of the Tire-Road Separation in Quarter-car Model

Authors: Quy Dang Nguyen, Reza Nakhaie Jazar

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The paper investigates vibration dynamics of tire-road separation for a quarter-car model; this separation model is developed to be close to the real situation considering the tire is able to separate from the ground plane. A set of piecewise linear mathematical models is developed and matches the in-contact and no-contact states to be considered as mother models for further investigations. The bound dynamics are numerically simulated in the time response and phase portraits. The separation analysis may determine which values of suspension parameters can delay and avoid the no-contact phenomenon, which results in improving ride comfort and eliminating the potentially dangerous oscillation. Finally, model verification is carried out in the MSC-ADAMS environment.

Keywords: quarter-car vibrations, tire-road separation, separation analysis, separation dynamics, ride comfort, ADAMS validation

Procedia PDF Downloads 54
490 A New Computational Package for Using in CFD and Other Problems (Third Edition)

Authors: Mohammad Reza Akhavan Khaleghi

Abstract:

This paper shows changes done to the Reduced Finite Element Method (RFEM) that its result will be the most powerful numerical method that has been proposed so far (some forms of this method are so powerful that they can approximate the most complex equations simply Laplace equation!). Finite Element Method (FEM) is a powerful numerical method that has been used successfully for the solution of the existing problems in various scientific and engineering fields such as its application in CFD. Many algorithms have been expressed based on FEM, but none have been used in popular CFD software. In this section, full monopoly is according to Finite Volume Method (FVM) due to better efficiency and adaptability with the physics of problems in comparison with FEM. It doesn't seem that FEM could compete with FVM unless it was fundamentally changed. This paper shows those changes and its result will be a powerful method that has much better performance in all subjects in comparison with FVM and another computational method. This method is not to compete with the finite volume method but to replace it.

Keywords: reduced finite element method, new computational package, new finite element formulation, new higher-order form, new isogeometric analysis

Procedia PDF Downloads 75
489 A Framework for ERP Project Evaluation Based on BSC Model: A Study in Iran

Authors: Mohammad Reza Ostad Ali Naghi Kashani, Esfanji Elia

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Nowadays, the amounts of companies which tend to have an Enterprise Resource Planning (ERP) application are increasing particularly in developing countries like Iran. ERP projects are expensive, time consuming, and complex, in addition the failure rate is high among these projects. It is important to know whether these projects could meet their goals or not. Furthermore, the area which should be improved should be identified. In this paper we made a framework to evaluate ERP projects success implementation. First, based on literature review we made a framework based on BSC model, financial, customer, processes, learning and knowledge, because of the importance of change management it was added to model. Then an organization was divided in three layers. We choose corporate, managerial, and operational levels. Then to find criteria to assess each aspect, we use Delphi method in two rounds. And for the second round we made a questionnaire and did some statistical tasks on them. Based on the statistical results some of them are accepted and others are rejected.

Keywords: ERP, BSC, ERP project evaluation, IT projects

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488 Exploring Individual and Team Approaches in Crafting Workplace Inclusivity for Deaf and Hard of Hearing Employees in Malaysia

Authors: Nor Wahiza Abdul Wahat, Nor Haniza Abdul Wahat, Siti Noormi Alias, Mohamad Sazali Shaari

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This study prepares the groundwork for the development of a strategic model and instrument for workplace inclusivity for deaf and hard-of-hearing employees in Malaysia. In the past, scholars have discussed inclusivity of workplaces to the extent to which employees feel they are significantly part of the organizational processes. Such processes include access to information, connectedness to colleagues and team members as well as their ability to participate in and influence decision-making processes. A qualitative study was conducted to explore on experiences of employed deaf and hard-of-hearing employees in a few Malaysian organizations. Data were collected from two focus group discussions involving male and female deaf and hard of hearing employees. Three in-depth interviews were also conducted with employer representatives. Generated themes highlighted individual, and team approaches towards crafting workplace inclusivity for deaf and hard of hearing employees in Malaysia. The adaptiveness of deaf and hard-of-hearing employees and social inclusion by colleagues were among the emerged sub-themes. This study allowed the researchers to further develop workplace inclusivity instruments and models for the benefit of deaf and hard of hearing Malaysian employees, as well as their employers.

Keywords: deaf, hard of hearing, workplace inclusivity, disabilities

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487 Point-Mutation in a Rationally Engineered Esterase Inverts its Enantioselectivity

Authors: Yasser Gaber, Mohamed Ismail, Serena Bisagni, Mohamad Takwa, Rajni Hatti-Kaul

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Enzymes are safe and selective catalysts. They skillfully catalyze chemical reactions; however, the native form is not usually suitable for industrial applications. Enzymes are therefore engineered by several techniques to meet the required catalytic task. Clopidogrel is recorded among the five best selling pharmaceutical in 2010 under the brand name Plavix. The commonly used route for production of the drug on an industrial scale is the synthesis of the racemic mixture followed by diastereomeric resolution to obtain the pure S isomer. The process consumes a lot of solvents and chemicals. We have evaluated a biocatalytic cleaner approach for asymmetric hydrolysis of racemic clopidogrel. Initial screening of a selected number of hydrolases showed only one enzyme EST to exhibit activity and selectivity towards the desired stereoisomer. As the crude EST is a mixture of several isoenzymes, a homology model of EST-1 was used in molecular dynamic simulations to study the interaction of the enzyme with R and S isomers of clopidogrel. Analysis of the geometric hindrances of the tetrahedral intermediates revealed a potential site for mutagenesis in order to improve the activity and the selectivity. Single point mutation showed dramatic increase in activity and inversion of the enantioselectivity (400 fold change in E value).

Keywords: biocatalysis, biotechnology, enzyme, protein engineering, molecular modeling

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486 Evaluation of Iranian Standard for Assessment of Liquefaction Potential of Cohesionless Soils Based on SPT

Authors: Reza Ziaie Moayad, Azam Kouhpeyma

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In-situ testing is preferred to evaluate the liquefaction potential in cohesionless soils due to high disturbance during sampling. Although new in-situ methods with high accuracy have been developed, standard penetration test, the simplest and the oldest in-situ test, is still used due to the profusion of the recorded data. This paper reviews the Iranian standard of evaluating liquefaction potential in soils (codes 525) and compares the liquefaction assessment methods based on SPT results on cohesionless soil in this standard with the international standards. To this, methods for assessing liquefaction potential which are presented by Cetin et al. (2004), Boulanger and Idriss (2014) are compared with what is presented in standard 525. It is found that although the procedure used in Iranian standard of evaluating the potential of liquefaction has not been updated according to the new findings, it is a conservative procedure.

Keywords: cohesionless soil, liquefaction, SPT, standard 525

Procedia PDF Downloads 139
485 Using Different Methods of Nanofabrication as a New Way to Activate Cement Replacement Materials in Concrete Industry

Authors: Azadeh Askarinejad, Parham Hayati, Reza Parchami, Parisa Hayati

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One of the most important industries and building operations causing carbon dioxide emission is the cement and concrete related industries so that cement production (including direct fuel for mining and transporting raw material) consumes approximately 6 million Btus per metric-ton, and releases about 1 metric-ton of CO2. Reducing the consumption of cement with simultaneous utilizing waste materials as cement replacement is preferred for reasons of environmental protection. Blended cements consist of different supplementary cementitious materials (SCM), such as fly ash, silica fume, Ground Granulated Blast Furnace Slag (GGBFS), limestone, natural pozzolans, etc. these materials should be chemically activated to show effective cementitious properties. The present review article reports three different methods of nanofabrication that were used for activation of two types of SCMs.

Keywords: nanofabrication, cement replacement materials, activation, concrete

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484 Determination of Bisphenol A and Uric Acid by Modified Single-Walled Carbon Nanotube with Magnesium Layered Hydroxide 3-(4-Methoxyphenyl)Propionic Acid Nanocomposite

Authors: Illyas Md Isa, Maryam Musfirah Che Sobry, Mohamad Syahrizal Ahmad, Nurashikin Abd Azis

Abstract:

A single-walled carbon nanotube (SWCNT) that has been modified with magnesium layered hydroxide 3-(4-methoxyphenyl)propionic acid nanocomposite was proposed for the determination of uric acid and bisphenol A by square wave voltammetry. The results obtained denote that MLH-MPP nanocomposites enhance the sensitivity of the voltammetry detection responses. The best performance is shown by the modified carbon nanotube paste electrode (CNTPE) with the composition of single-walled carbon nanotube: magnesium layered hydroxide 3-(4-methoxyphenyl)propionic acid nanocomposite at 100:15 (% w/w). The linear range where the sensor works well is within the concentration 1.0 10-7 – 1.0 10-4 and 3.0 10-7 – 1.0 10-4 for uric acid and bisphenol A respectively with the limit of detection of 1.0 10-7 M for both organics. The interferences of uric acid and bisphenol A with other organic were studied and most of them did not interfere. The results shown for each experimental parameter on the proposed CNTPE showed that it has high sensitivity, good selectivity, repeatability and reproducibility. Therefore, the modified CNTPE can be used for the determination of uric acid and bisphenol A in real samples such as blood, plastic bottles and foods.

Keywords: bisphenol A, magnesium layered hydroxide 3-(4-methoxyphenyl)propionic acid nanocomposite, Nanocomposite, uric acid

Procedia PDF Downloads 181
483 Nanofluid Flow Heat Transfer Through Ducts with Different Cross-Sections

Authors: Amir Dehshiri, Mohammad Reza Salimpour

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In the present article, we investigate experimental laminar forced convective heat transfer specifications of TiO2/water nanofluids through conduits with different cross sections. We check the effects of different parameters such as cross-sectional shape, Reynolds number and concentration of nanoparticles in stable suspension on increasing convective heat transfer by designing and assembling of an experimental apparatus. The results demonstrate adding a little amount of nanoparticles to the base fluid, improves heat transfer behavior in conduits. Moreover, conduit with circular cross-section has better performance compared to the square and triangular cross sections. However, conduits with square and triangular cross sections have more relative heat transfer enhancement than conduit with circular cross section.

Keywords: nanofluid, cross-sectional shape, TiO2, convection

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482 Effectiveness of Jackfruit Seed Starch as Coagulant Aid in Landfill Leachate Treatment

Authors: Mohd Suffian Yusoff, Noor Aina Mohamad Zuki, Mohd Faiz Muaz Ahmad Zamri

Abstract:

Currently, aluminium sulphate (alum), ferric chloride and polyaluminium chloride (PAC) are the most common coagulants being used for leachate coagulation-flocculation treatment. However, the impact of these residual’s coagulants have sparked huge concern ceaselessly. Therefore, development of natural coagulant as an alternative coagulant for treatment process has been given full attentions. In this attempt jackfruit seed starch (JSS) was produce by extraction method. The removal efficiency was determined using jar test method. The removal of organic matter and ammonia were compared between JSS used in powder form and diluted form in leachate. The yield of starch from the extraction method was 33.17 % with light brown in colour. The removal of turbidity was the highest at pH 8 for both diluted and powdered JSS with 38% and 8.7% of removal. While for colour removal the diluted JSS showed 18.19% of removal compared to powdered JSS. The diluted JSS also showed the highest removal of suspended solid with 3.5% compared to powdered JSS with 2.8%. Instead of coagulant, JSS as coagulant aid has succeed to reduce the dosage of PAC from 900 mg/L to 528 mg/L by maintaining colour and turbidity removal up to 94% and 92 % respectively. The JSS coagulant also has decreased the negative charge of the leachate nearly to the neutral charge (0.209 mv). The result proved that JSS was more effective to be used as coagulant aid landfill leachate treatment.

Keywords: landfill leachate, natural coagulant, jackfruit seed starch, coagulant

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481 Influence of Surface Area on Dissolution of Additively Manufactured Polyvinyl Alcohol Tablets

Authors: Seyedebrahim Afkhami, Meisam Abdi, Reza Baserinia

Abstract:

Additive manufacturing is revolutionising production in different industries, including pharmaceuticals. This case study explores the influence of surface area on the dissolution of additively manufactured polyvinyl alcohol parts as a polymer candidate. Specimens of different geometries and constant mass were fabricated using a Fused Deposition Modelling 3D printer. The dissolution behaviour of these samples was compared with respect to their surface area. Improved and accelerated dissolution was observed for samples with a larger surface area. This study highlights the capabilities of additive manufacturing to produce samples of complex geometries that cannot be manufactured otherwise to control the dissolution behaviour for pharmaceutical and biopharmaceutical applications.

Keywords: additive manufacturing, polymer dissolution, fused deposition modelling, geometry optimization

Procedia PDF Downloads 55