Search results for: Pedram Hatami Abdullah
239 Hot Corrosion Susceptibility of Uncoated Boiler Tubes during High Vanadium Containing Fuel Oil Operation in Boiler Applications
Authors: Nicole Laws, William L. Roberts, Saumitra Saxena, Krishnamurthy Anand, Sreenivasa Gubba, Ziad Dawood, Aiping Chen
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Boiler-fired power plants that operate steam turbines in Saudi Arabia use vanadium-containing fuel oil. In a super- or sub-critical steam cycle, the skin temperature of boiler tube metal can reach close to 600-1000°C depending on the location of the tubes. At high temperatures, corrosion by the sodium-vanadium-oxygen-sulfur eutectic can become a significant risk. The experimental work utilized a state-of-the-art high-temperature, high-pressure burner rig at KAUST, King Abdullah University of Science and Technology. To establish corrosion rates of different boiler tubes and materials, SA 213 T12, SA 213 T22, SA 213 T91, and Inconel 600, were used under various corrosive media, including vanadium to sulfur levels and vanadium to sodium ratios. The results obtained from the experiments establish a corrosion rate map for the materials involved and layout an empirical framework to rank the life of boiler tube materials under different operating conditions. Safe windows of operation are proposed for burning liquid fuels under varying vanadium, sodium, and sulfur levels before corrosion rates become a matter of significance under high-temperature conditionsKeywords: boiler tube life, hot corrosion, steam boilers, vanadium in fuel oil
Procedia PDF Downloads 233238 Perception of Risks of the Telecommunication Towers in Malaysia: A Qualitative Inquiry
Authors: Y. Kamarulzaman, A. Madun, F. D. Yusop, N. Abdullah, N. K. Hoong
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In 2011, the Malaysian Government has initiated a nationwide project called 1BestariNet which will adopt the using of technology in teaching and learning, resulting in the construction of telecommunication towers inside the public schools’ premise. Using qualitative approach, this study investigated public perception of risks associated with the project, particularly the telecommunication towers. Data collection involved observation and in-depth interviews with 22 individuals consist of a segment of public that was anxious about the risks of radio frequency electromagnetic field (RFEMF) which include two employees of telecommunication companies (telcos) and five employees of Government agencies. Observation of the location of the towers at 10 public schools, a public forum, and media reports provide valuable information in our analysis. The study finds that the main concern is related to the health risks. This study also shows that it is not easy for the Government to manage public perception mainly because it involves public trust. We find that risk perception is related with public trust, as well as the perceived benefits and level of knowledge. Efficient communication and continuous engagement with the local communities help to build and maintain public trust, reduce public fear and anxiety, hence mitigating the risk perception among the public.Keywords: risk perception, risk communication, trust, telecommunication tower, radio frequency electromagnetic field (RFEMF)
Procedia PDF Downloads 320237 Effect of Segregation Pattern of Mn, Si, and C on through Thickness Microstructure and Properties of Hot Rolled Steel
Authors: Waleed M. Al-Othman, Hamid Bayati, Abdullah Al-Shahrani, Haitham Al-Jabr
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Pearlite bands commonly form parallel to the surface of the hot rolled steel and have significant influence on the properties of the steel. This study investigated the correlation between segregation pattern of Mn, Si, C and formation of the pearlite bands in hot rolled Gr 60 steel plate. Microstructural study indicated formation of a distinguished thick band at centerline of the plate with number of parallel bands through thickness of the steel plate. The thickness, frequency, and continuity of the bands are reduced from mid-thickness toward external surface of the steel plate. Analysis showed a noticeable increase of C, Si and Mn levels within the bands. Such alloying segregation takes place during metal solidification. EDS analysis verified presence of particles rich in Ti, Nb, Mn, C, N, within the bands. Texture analysis by Electron Backscatter Detector (EBSD) indicated the grains size/misorientation can noticeably change within the bands. Effect of banding on through-thickness properties of the steel was examined by carrying out microhardness, toughness and tensile tests. Results suggest the Mn and C contents are changed in sinusoidal pattern through thickness of the hot rolled plate and pearlite bands are formed at the peaks of this sinusoidal segregation pattern. Changes in grain size/misorientation, formation of highly alloyed particles, and pearlite within these bands, facilitate crack formation along boundaries of these bands.Keywords: pearlite band, alloying segregation, hot rolling, Ti, Nb, N, C
Procedia PDF Downloads 137236 Steps towards the Development of National Health Data Standards in Developing Countries
Authors: Abdullah I. Alkraiji, Thomas W. Jackson, Ian Murray
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The proliferation of health data standards today is somewhat overlapping and conflicting, resulting in market confusion and leading to increasing proprietary interests. The government role and support in standardization for health data are thought to be crucial in order to establish credible standards for the next decade, to maximize interoperability across the health sector, and to decrease the risks associated with the implementation of non-standard systems. The normative literature missed out the exploration of the different steps required to be undertaken by the government towards the development of national health data standards. Based on the lessons learned from a qualitative study investigating the different issues to the adoption of health data standards in the major tertiary hospitals in Saudi Arabia and the opinions and feedback from different experts in the areas of data exchange and standards and medical informatics in Saudi Arabia and UK, a list of steps required towards the development of national health data standards was constructed. Main steps are the existence of: a national formal reference for health data standards, an agreed national strategic direction for medical data exchange, a national medical information management plan and a national accreditation body, and more important is the change management at the national and organizational level. The outcome of this study can be used by academics and practitioners to develop the planning of health data standards, and in particular those in developing countries.Keywords: interoperabilty, medical data exchange, health data standards, case study, Saudi Arabia
Procedia PDF Downloads 338235 Exploring the Challenges and Opportunities in Clinical Waste Management: The Case of Private Clinics, Selangor, Malaysia
Authors: Golyasamin Khanehzaei, Mohd. Bakri Ishak, Ahmad Makmom Hj Abdullah, Latifah Abd Manaf
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Abstract—Management of clinical waste is a critical problem worldwide. Immediate attention is required to manage the clinical waste in an appropriate way in newly developing economy country such as Malaysia. The increasing amount of clinical waste generated is resulted from rapid urbanization and growing number of private health care facilities in developing countries such as Malaysia. In order to develop a sensible clinical waste management system and improvement of the management, information on factors affecting clinical waste generation has the crucial role. This paper is the study of management characteristics of clinical waste and the level of efficiency of clinical waste management systems operating in private clinics located in Selangor, Malaysia. Are they following the proper international standards? By taking all of this in consideration the aim of this paper is to identify and discuss the current trend, current challenges and also the present opportunities among the challenges of clinical waste management in private clinics of Selangor, Malaysia. The SWOT analysis was characterized for the evaluation of strengths, weaknesses, opportunities and threats. The methodology for this study was constituted of direct observation, Informal interviews, Conducting SWOT analysis, conduction of one sustainability dimensions analysis and application. The results show that clinical waste management in private clinics is far from an ideal model.Keywords: clinical waste, SWOT analysis, Selangor, Malaysia
Procedia PDF Downloads 348234 Managerial Overconfidence, Payout Policy, and Corporate Governance: Evidence from UK Companies
Authors: Abdullah AlGhazali, Richard Fairchild, Yilmaz Guney
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We examine the effect of managerial overconfidence on UK firms’ payout policy for the period 2000 to 2012. The analysis incorporates, in addition to common firm-specific factors, a wide range of corporate governance factors and managerial characteristics that have been documented to affect the relationship between overconfidence and payout policy. Our results are robust to several estimation considerations. The findings show that the influence of overconfident CEOs on the amount of, and the propensity to pay, dividends is significant within the UK context. Specifically, we detect that there is a reduction in dividend payments in firms managed by overconfident managers compared to their non-overconfident counterparts. Moreover, we affirm that cash flows, firm size and profitability are positively correlated, while leverage, firm growth and investment are negatively correlated with the amount of and propensity to pay dividends. Interestingly, we demonstrate that firms with the potential for undervaluation reduce dividend payments. Some of the corporate governance factors are shown to motivate firms to pay more dividends while these factors seem to have no influence on the propensity to pay dividends. The results also show that in general higher overconfidence leads to more share repurchases but the lower total payout. Overall, managerial overconfidence should be considered as an important factor influencing payout policy in addition to other known factors.Keywords: dividends, repurchases, UK firms, overconfidence, corporate governance, undervaluation
Procedia PDF Downloads 268233 Storage Durations Affect the Physico-Chemical Characteristics of Physalis Minima L.
Authors: Norhanizan U., S. H. Ahmad, N. A. P. Abdullah, G. B. Saleh
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Physalis minima from the family of Solanaceae is one of the promising fruits which contains the high amount of vitamin C and other antioxidants as well. However, it is a perishable fruit where the deterioration process will commence if the fruits are not stored in proper conditions. There is not much work has been carried out to study the effects of storage durations on Physalis fruit. Therefore, this study was conducted to determine the effects of 0, 3, 6, and 9 days of storage on postharvest quality of Physalis minima fruits. Total of 120g of uniform sizes of fruits (2.3 to 2.5g) were used for each replication and the experiment was repeated thrice. The fruits were divided equally into four groups with each group labeled according to the days of storage. The fruits were then stored in the cool room for nine days with temperature maintain at 12 ° C. The fruits were analyzed for weight loss, firmness, color (L*, C* and hue angle), titratable acidity (TA), soluble solids concentrations (SSC), pH and ascorbic acids. Data were analyzed using analysis of variance and means was separated using least significant difference (LSD). The storage durations affect the quality characteristics of the fruits. On the day 9, the average of fruit weight loss and fruit firmness decreased about 21 and 24% respectively. The level of ascorbic acids and titrable acidity were also decreased while the soluble solids concentration increased during storage. Thus, in order to retain the quality of the fruits, it is recommended that the Physalis fruit can be stored only up to 6 days at 12 ° C.Keywords: fruit quality, Physalis minima, Solanaceae, storage durations
Procedia PDF Downloads 282232 The Impact of Motivation, Trust, and National Cultural Differences on Knowledge Sharing within the Context of Electronic Mail
Authors: Said Abdullah Al Saifi
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The goal of this research is to examine the impact of trust, motivation, and national culture on knowledge sharing within the context of electronic mail. This study is quantitative and survey based. In order to conduct the research, 200 students from a leading university in New Zealand were chosen randomly to participate in a questionnaire survey. Motivation and trust were found to be significantly and positively related to knowledge sharing. The research findings illustrated that face saving, face gaining, and individualism positively moderates the relationship between motivation and knowledge sharing. In addition, collectivism culture negatively moderates the relationship between motivation and knowledge sharing. Moreover, the research findings reveal that face saving, individualism, and collectivism culture positively moderate the relationship between trust and knowledge sharing. In addition, face gaining culture negatively moderates the relationship between trust and knowledge sharing. This study sets out several implications for researchers and practitioners. The study produces an integrative model that shows how attributes of national culture impact knowledge sharing through the use of emails. A better understanding of the relationship between knowledge sharing and trust, motivation, and national culture differences will increase individuals’ ability to make wise choices when sharing knowledge with those from different cultures.Keywords: knowledge sharing, motivation, national culture, trust
Procedia PDF Downloads 348231 Causal Relationship between Macro-Economic Indicators and Fund Unit Price Behaviour: Evidence from Malaysian Equity Unit Trust Fund Industry
Authors: Anwar Hasan Abdullah Othman, Ahamed Kameel, Hasanuddeen Abdul Aziz
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In this study, an attempt has been made to investigate the relationship specifically the causal relation between fund unit prices of Islamic equity unit trust fund which measure by fund NAV and the selected macro-economic variables of Malaysian economy by using VECM causality test and Granger causality test. Monthly data has been used from Jan, 2006 to Dec, 2012 for all the variables. The findings of the study showed that industrial production index, political election and financial crisis are the only variables having unidirectional causal relationship with fund unit price. However, the global oil prices is having bidirectional causality with fund NAV. Thus, it is concluded that the equity unit trust fund industry in Malaysia is an inefficient market with respect to the industrial production index, global oil prices, political election and financial crisis. However, the market is approaching towards informational efficiency at least with respect to four macroeconomic variables, treasury bill rate, money supply, foreign exchange rate and corruption index.Keywords: fund unit price, unit trust industry, Malaysia, macroeconomic variables, causality
Procedia PDF Downloads 470230 3D Numerical Studies on Jets Acoustic Characteristics of Chevron Nozzles for Aerospace Applications
Authors: R. Kanmaniraja, R. Freshipali, J. Abdullah, K. Niranjan, K. Balasubramani, V. R. Sanal Kumar
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The present environmental issues have made aircraft jet noise reduction a crucial problem in aero-acoustics research. Acoustic studies reveal that addition of chevrons to the nozzle reduces the sound pressure level reasonably with acceptable reduction in performance. In this paper comprehensive numerical studies on acoustic characteristics of different types of chevron nozzles have been carried out with non-reacting flows for the shape optimization of chevrons in supersonic nozzles for aerospace applications. The numerical studies have been carried out using a validated steady 3D density based, k-ε turbulence model. In this paper chevron with sharp edge, flat edge, round edge and U-type edge are selected for the jet acoustic characterization of supersonic nozzles. We observed that compared to the base model a case with round-shaped chevron nozzle could reduce 4.13% acoustic level with 0.6% thrust loss. We concluded that the prudent selection of the chevron shape will enable an appreciable reduction of the aircraft jet noise without compromising its overall performance. It is evident from the present numerical simulations that k-ε model can predict reasonably well the acoustic level of chevron supersonic nozzles for its shape optimization.Keywords: supersonic nozzle, Chevron, acoustic level, shape optimization of Chevron nozzles, jet noise suppression
Procedia PDF Downloads 516229 Modified Single-Folded Potentials for the Alpha-²⁴Mg and Alpha-²⁸Si Elastic Scattering
Authors: M. N. A. Abdullah, Pritha Roy, R. R. Shil, D. R. Sarker
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Alpha-nucleus interaction is obscured because it produces enhanced cross-sections at large scattering angles known as anomaly in large angle scattering (ALAS). ALAS is prominent in the elastic scattering of α-particles as well as in non-elastic processes involving α-particles for incident energies up to 50 MeV and for targets of mass A ≤ 50. The Woods-Saxon type of optical model potential fails to describe the processes in a consistent manner. Folded potential is a good candidate and often used to construct the potential which is derived from the microscopic as well as semi-microscopic folding calculations. The present work reports the analyses of the elastic scattering of α-particles from ²⁴Mg and ²⁸Si at Eα=22-100 MeV and 14.4-120 MeV incident energies respectively in terms of the modified single-folded (MSF) potential. To derive the MSF potential, we take the view that the nucleons in the target nuclei ²⁴Mg and ²⁸Si are primarily in α-like clusters and the rest of the time in unclustered nucleonic configuration. The MSF potential, found in this study, does not need any renormalization over the whole range of incident α energies, and the renormalization factor has been found to be exactly 1 for both the targets. The best-fit parameters yield 4Aα = 21 and AN = 3 for α-²⁴Mg potential, and 4Aα = 26 and AN = 2 for α-²⁸Si potential in time-average pictures. The root-mean-square radii of both ²⁴Mg and ²⁸Si are also deduced, and the results obtained from this work agree well with the outcomes of other studies.Keywords: elastic scattering, optical model, folded potential, renormalization
Procedia PDF Downloads 224228 Performance Tracking of Thermal Plant Systems of Kuwait and Impact on the Environment
Authors: Abdullah Alharbi
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Purpose: This research seeks to take a holistic strategic evaluation of the thermal power plants in Kuwait at both policy and technical level in order to allow a systematic retrofitting program. The new world order in energy generation and consumption demand that sources of energy can safeguard the use of natural resources and generate minimal impacts on the environment. For Kuwait, the energy used per capita is mainly associated with desalination plants. The overall impact of thermal power plant installations manifests indisposed of seawater and the health of marine life. Design/methodology/approach: The research adopts a case study based evaluation of performance data and documents of thermal plant installations in Kuwait. Findings: Research findings on the performance of existing thermal plants demand policy benchmarking with internationally acceptable standards in order to create clarity on decisions regarding demolition, retrofitting, or renewal. Research implications: This research has the potential to strategically inform and influence the piecemeal changes to power plants, including the replacement of power generation equipment, considering the varied technologies for thermal plants. Originality/value: This research provides evidence based data that can be useful for influencing operational efficiency after a holistic evaluation of existing capacity in comparison with future demands.Keywords: energy, Kuwait, performance, stainability, tracking, thermal plant
Procedia PDF Downloads 98227 Environmental Online Campaigns Through Website Interactivity: The Case of Malaysia Environmental NGOs (MENGO)
Authors: Mohd Fadzil Mohd Idris, Aida Nasirah Abdullah, Kalthom Husain, Hanipah Hussin
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Online campaigns reflect all the advantages; namely speed, low cost, accessibility, customization, interactivity, and persuasive ability over other media channels. Normally via websites, expensive campaigns could be done not only faster and cheaper, but also successfully. Web interactivity seems to be highly beneficial to ENGOs in advocating environmental campaigns and trigger interaction. This paper looks into the environmental online campaigns through websites of the environmental NGOs in Malaysia (MENGO); particularly on how is web interactivity structured and employed by the selected the MENGO to conduct campaigns on important issues and encourage dialogue among the audience. In this study, a quantitative method for website content analysis was conducted to investigate the availability of the coded units and to determine on which level(s) the units were placed. Twelve (12) interactivity features were coded, including the placement of units of analysis for interactivity category as units of analysis until the fourth level (Level 0-Level 3). The result demonstrates how the MENGO do not effectively structure and employ the web interactivity to conduct campaigns on important issues and encourage dialogue among the audience. It is suggested that the MENGO should redevelop the interactive website in order to effectively advocate environmental campaigns on important issues and encourage dialogue among the audience.Keywords: environmental NGOs (ENGO), Malaysia environmental NGOs (MENGO), internet, website, online campaigns, web interactivity
Procedia PDF Downloads 440226 Prone Positioning and Clinical Outcomes of Mechanically Ventilated Patients with Severe Acute Respiratory Distress Syndrome
Authors: Maha Salah Abdullah Ismail, Mahmoud M. Alsagheir, Mohammed Salah Abd Allah
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Acute respiratory distress syndrome (ARDS) is characterized by permeability pulmonary edema and refractory hypoxemia. Lung-protective ventilation is still the key of better outcome in ARDS. Prone position reduces the trans-pulmonary pressure gradient, recruiting collapsed regions of the lung without increasing airway pressure or hyperinflation. Prone ventilation showed improved oxygenation and improved outcomes in severe hypoxemic patients with ARDS. This study evaluates the effect of prone positioning on mechanically ventilated patients with ARDS. A quasi-experimental design was carried out at Critical Care Units, on 60 patients. Two tools were utilized to collect data; Socio demographic, medical and clinical outcomes data sheet. Results of the present study indicated that prone position improves oxygenation in patients with severe respiratory distress syndrome. The study recommended that use prone position in patients with severe ARDS, as early as possible and for long sessions. Also, replication of this study on larger probability sample at the different geographical location is highly recommended.Keywords: acute respiratory distress syndrome, critical care, mechanical ventilation, prone position
Procedia PDF Downloads 538225 The Possible Role of the Endoneurial Fibroblast-like Cells in Resolution of the Endoneurial Edema Following Nerve Crush Injury
Authors: Faris M. Altaf, Abdullah M Elkeshy
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Forty-two albino male rats aged between 30 and 40 days (weighted 200 g to 250 g) were used in the present study. The left sural nerves of 36 rats were subjected to crush injury at 1 to 6 weeks intervals using 6 animals at each interval. The right and left sural nerves of the rest 6 rats were used as a control. After 2 weeks of the crush injury, the endoneurium showed channel-like spaces that were lined by the fibroblast-like cells and collagen bundles. These channels contained degenerated myelin and were connected with the perivascular and subperineurial spaces. Some of the flattened fibroblast-like cells were arranged in several layers in the subperineurial and perivascular spaces, forming barrier-like cellular sheets localizing the endoneurial edema in these spaces. Fibroblast-like cells also wrapped the regenerating nerve fibers by their branching cytoplasmic processes. At the end of the third week, the flattened fibroblasts formed nearly continuous sheets in the subperineurial and perivascular spaces. Macrophages were frequently noticed between these cellular barrier-like sheets and in the subperineurial and perivascular spaces. Conclusion: it could be concluded that the endoneurial fibroblast-like cells form barrier-like cellular sheets that localized the endoneurial edema in the subperineurial and perivascular spaces and create also the endoneurial channel-like spaces containing degenerated myelin and endoneurial edema helping the resolution of such edema.Keywords: sural nerve, endoneurial fibroblast-like cells, endoneurial edema, barrier-like and channel-like spaces
Procedia PDF Downloads 343224 Acceptance towards Counselling Services among Flood Victims in Selangor
Authors: Husni Mohd Radzi, Lilie Zahara Ramly, Sapora Sipon, Salhah Abdullah
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Malaysia have been experiencing series of huge floods all around the country for the past decades despide planned development done by local authorities. The floods incurred due to factors like natural climate change or man-made disaster. Floods have caused a lot of damages, destructions and losses in term of infrastructure, financial implications and physical health. However, other damaging aspect was not being given much attention are the psychological need of the flood victim. The traumatic impact from the natural disaster like floods may cause serious psychological and spiritual deterioration. Many flood relief shelters in the past did not provide counseling services for flood victims to consult, and as a result, it contributes to added stress among the flood victims, as the issue were not being addressed. Some studies indicates that flood victims did not look for counseling service being offered. A total of 257 flood victim was involved in this study. Main area of the study was Kg Bukit Changgang, Kg. Rancangan Tanah Belia, Kg. Labohan Dagang and Kg.Olak Lempit in Kuala Langat, Selangor. The flood victims have responded to the survey given and the data was analyze using SPSS for descriptive information and other measures. At least 13 victims were reported to have experienced moderate to severe level of stress and anxiety over the flood disaster incidents and a total of 88 respondents admitted to have at least thought and consider getting counseling service.Keywords: perception, acceptance towards counseling, counseling service for flood victim, disaster
Procedia PDF Downloads 319223 The Causes and Effects of Housing Project Abandonment in Malaysia
Authors: Abdul Aziz Abdullah, Anuar Alias, Khor Hooi Ting, Guan Ngah Mei
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One of the major sectors which contribute significant growth to socio-economic development is the construction and development industry. This industry is most badly hurt during the 1997 and 2008 economic crisis thus causing many government and private projects to be deferred and abandoned. The purpose of this study is to examine the causes and effects of housing project abandonment in Malaysia. This objective is achieved through rigorous review of literatures and documents related to housing and abandoned housing project. The finding revealed there are several causes of housing project abandonment. The significant causes are: economic recession, inadequacy of finance, poor marketing and sales strategies, technical problems faced during construction, problems caused by compensations demanded by squatters for resettlement, insolvency of contractor, cost overrun and currency fluctuation amongst others. However the alarming effect of housing project is: house buyers of abandoned project have the monthly payment although the house is delivered to house buy. In other case house buyers have to entangle in many legal action with the financial institution. This finding provides the various ministries in the Government some insights on real causes and effects of abandoned project. Perhaps this finding can enhance the current solution the Ministry of Housing Local Government on addressing the prevailing issue of reviving existing abandoned project in the country.Keywords: abandoned project, abandonment, housing project, ministry of housing and local government, causes and effect
Procedia PDF Downloads 540222 Evaluating the Green Marketing Performance, an Empirical Study for Dates Factories in Al-Kharj Province, Saudi Arabia
Authors: Saleh Abdullah Dabil
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The research aims to survey the dates factories in Al-Kharj Province, and then identify the nature of a series of different production processes and the using of raw materials, as well as their finished products, and the extent of their impact on the environment or consumers satisfaction. Twenty dates factories were selected according to their willingness to participate. The participants of dates factories consist of approximately 40 % of all dates factories in Al-Kharj province. All of the dates factories which were visited were observed. The research team also administered number of questionnaires to the public to know their satisfaction levels of the dates products as well as their suggestions. It is accounted to 237 participants who gave their opinion about the dates products and their suggestions. This study is one of rare studies about green marketing in dates factories. What is new about this study is that it depends upon both of the managers and consumers as well as the researchers to look into the factories’ production line and to observe the level of satisfaction. The study resulted in a very good ending because that the green marketing of dates is in its highest level. This indicates that the factories in general using natural materials and no bad materials or subsides used in the production, the levels of satisfaction by consumers are very good, preferring mostly lose product of dates. The preference of lose dates means the tendency to use the dates in their natural product. The recommendations of this study suggest solving marketing problems in transforming raw dates into manufacturing products. This includes biscuits and other types of sweet products.Keywords: green marketing, dates factories, environment impact, consumer satisfaction
Procedia PDF Downloads 271221 Effect of Weld Build-up on the Mechanical Performance of Railway Wheels
Authors: Abdullah Kaymakci, Daniel M. Madyira, Hilda Moseme
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Repairing railway wheels by weld build-up is one of the technological solutions that have been applied in the past. However, the effects of this process on the material properties are not well established. The effects of the weld build-up on the mechanical properties of the wheel material in comparison to the required mechanical properties for proper service performance were investigated in this study. A turning process was used to remove the worn surface from the railway wheel. During this process 5mm thickness was removed to ensure that, if there was any weld build-up done in the previous years, it was removed. This was followed by welding a round bar on the sides of the wheel to provide build-up guide. There were two welding processes performed, namely submerged arc welding (SAW) and gas metal arc welding (GMAW). Submerged arc welding (SAW) was used to build up weld on one rim while the other rim was just left with metal arc welding of the round bar at the edges. Both processes produced hardness values that were lower than that of the parent material of 195 HV as the GMAW welds had an average of 184 HV and SAW had an average of 194 HV. Whilst a number of defects were noted on the GMAW welds at both macro and micro levels, SAW welds had less defects and they were all micro defects. All the microstructures were ferritic but with differences in grain sizes. Furthermore, in the SAW weld build up, the grains of the weld build-up appeared to be elongated which was a result of the cooling rate. Using GMAW instead of SAW would result in improved wear and fatigue performance.Keywords: submerged arc welding, gas metal arc welding, railway wheel, microstructure, micro hardness
Procedia PDF Downloads 303220 Genotyping of Salmonella enterica Collected from Poultry Farms Located in Riyadh, KSA by Multiplex-PCR
Authors: Moussa I. Mohamed, Turki, K. A. Al-Faraj, Abdullah A. Al-Arfaj, Ashgan M. Hessain
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The objective of the present study is to detect the incidences of Salmonella enterica from different poultry farms located in Egypt on molecular basis. During the summer of 2012, a total of 1800 cloacal swabs were collected from poultry farms located I Cairo, Egypt to be subjected for isolation of Salmonella enteric. Moreover, a total of 300 samples of poultry and poultry products were collected from different retail establishment markets in Cairo, Egypt including, 150 local whole frozen chickens, 50 imported whole frozen chickens, 100 local chicken cut samples. The highest rate of isolation 8% was obtained from imported frozen chickens and local chicken cuts, followed by local frozen chickens 6.66% and finally rectal swabs from apparently health chickens 6.4 %. Salmonella Typhimurium and Salmonella Enteritidis were most frequent among the total Salmonella isolates. Multiplex-PCR for the rapid detection of Salmonella Typhimurium and Salmonella Enteritidis from field samples especially after pre-enrichment on Rappaport-Vassiliadis (RV) selective broth (PCR-RV), revealed the same positive samples. Therefore PCR-RV technique is rabid, time saving and applicable to detect Salmonella serovars directly from chicken samples. Moreover, detecting Salmonella Typhimurium and Salmonella Enteritidis by this assay was carried out within 2 days opposed to 5–6 d by the bacteriological and serological methods.Keywords: Salmonella enterica, Salmonella typhimurium, Salmonella enteritidis enrichment, multiplex-PCR
Procedia PDF Downloads 374219 Solving Process Planning, Weighted Earliest Due Date Scheduling and Weighted Due Date Assignment Using Simulated Annealing and Evolutionary Strategies
Authors: Halil Ibrahim Demir, Abdullah Hulusi Kokcam, Fuat Simsir, Özer Uygun
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Traditionally, three important manufacturing functions which are process planning, scheduling and due-date assignment are performed sequentially and separately. Although there are numerous works on the integration of process planning and scheduling and plenty of works focusing on scheduling with due date assignment, there are only a few works on integrated process planning, scheduling and due-date assignment. Although due-dates are determined without taking into account of weights of the customers in the literature, here weighted due-date assignment is employed to get better performance. Jobs are scheduled according to weighted earliest due date dispatching rule and due dates are determined according to some popular due date assignment methods by taking into account of the weights of each job. Simulated Annealing, Evolutionary Strategies, Random Search, hybrid of Random Search and Simulated Annealing, and hybrid of Random Search and Evolutionary Strategies, are applied as solution techniques. Three important manufacturing functions are integrated step-by-step and higher integration levels are found better. Search meta-heuristics are found to be very useful while improving performance measure.Keywords: process planning, weighted scheduling, weighted due-date assignment, simulated annealing, evolutionary strategies, hybrid searches
Procedia PDF Downloads 462218 Studying the Effectiveness of Using Narrative Animation on Students’ Understanding of Complex Scientific Concepts
Authors: Atoum Abdullah
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The purpose of this research is to determine the extent to which computer animation and narration affect students’ understanding of complex scientific concepts and improve their exam performance, this is compared to traditional lectures that include PowerPoints with texts and static images. A mixed-method design in data collection was used, including quantitative and qualitative data. Quantitative data was collected using a pre and post-test method and a close-ended questionnaire. Qualitative data was collected through an open-ended questionnaire. A pre and posttest strategy was used to measure the level of students’ understanding with and without the use of animation. The test included multiple-choice questions to test factual knowledge, open-ended questions to test conceptual knowledge, and to label the diagram questions to test application knowledge. The results showed that students on average, performed significantly higher on the posttest as compared to the pretest on all areas of acquired knowledge. However, the increase in the posttest score with respect to the acquisition of conceptual and application knowledge was higher compared to the increase in the posttest score with respect to the acquisition of factual knowledge. This result demonstrates that animation is more beneficial when acquiring deeper, conceptual, and cognitive knowledge than when only factual knowledge is acquired.Keywords: animation, narration, science, teaching
Procedia PDF Downloads 170217 Evaluation of Medication Errors in Outpatient Pharmacies: Electronic Prescription System vs. Paper System
Authors: Mera Ababneh, Sayer Al-Azzam, Karem Alzoubi, Abeer Rababa'h
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Background: Medication errors are among the most common medical errors. Their occurrences result in patient’s mortality, morbidity, and additional healthcare costs. Continuous monitoring and detection is required. Objectives: The aim of this study was to compare medication errors in outpatient’s prescriptions in two different hospitals (paper system vs. electronic system). Methods: This was a cross sectional observational study conducted in two major hospitals; King Abdullah University Hospital (KAUH) and Princess Bassma Teaching Hospital (PBTH) over three months period. Data collection was conducted by two trained pharmacists at each site. During the study period, medication prescriptions and dispensing procedures were screened for medication errors in both participating centers by two trained pharmacist. Results: In the electronic prescription hospital, 2500 prescriptions were screened in which 631 medication errors were detected. Prescription errors were 231 (36.6%), and dispensing errors were 400 (63.4%) of all errors. On the other side, analysis of 2500 prescriptions in paper-based hospital revealed 3714 medication errors, of which 288 (7.8%) were prescription errors, and 3426 (92.2%) were dispensing errors. A significant number of 2496 (67.2%) were inadequately and/or inappropriately labeled. Conclusion: This study provides insight for healthcare policy makers, professionals, and administrators to invest in advanced technology systems, education, and epidemiological surveillance programs to minimize medication errors.Keywords: medication errors, prescription errors, dispensing errors, electronic prescription, handwritten prescription
Procedia PDF Downloads 280216 Magnetic Survey for the Delineation of Concrete Pillars in Geotechnical Investigation for Site Characterization
Authors: Nuraddeen Usman, Khiruddin Abdullah, Mohd Nawawi, Amin Khalil Ismail
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A magnetic survey is carried out in order to locate the remains of construction items, specifically concrete pillars. The conventional Euler deconvolution technique can perform the task but it requires the use of fixed structural index (SI) and the construction items are made of materials with different shapes which require different SI (unknown). A Euler deconvolution technique that estimate background, horizontal coordinate (xo and yo), depth and structural index (SI) simultaneously is prepared and used for this task. The synthetic model study carried indicated the new methodology can give a good estimate of location and does not depend on magnetic latitude. For field data, both the total magnetic field and gradiometer reading had been collected simultaneously. The computed vertical derivatives and gradiometer readings are compared and they have shown good correlation signifying the effectiveness of the method. The filtering is carried out using automated procedure, analytic signal and other traditional techniques. The clustered depth solutions coincided with the high amplitude/values of analytic signal and these are the possible target positions of the concrete pillars being sought. The targets under investigation are interpreted to be located at the depth between 2.8 to 9.4 meters. More follow up survey is recommended as this mark the preliminary stage of the work.Keywords: concrete pillar, magnetic survey, geotechnical investigation, Euler Deconvolution
Procedia PDF Downloads 258215 Designing the First Oil Tanker Shipyard Facility in Kuwait
Authors: Fatma Al Abdullah, Shahad Al Ameer, Ritaj Jaragh, Fatimah Khajah, Rawan Qambar, Amr Nounou
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Kuwait currently manufactures its tankers in foreign countries. Oil tankers play a role in the supply chain of the oil industry. Therefore, with Kuwait’s sufficient financial resources, the country should secure itself strategically in order to protect its oil industry to sustain economic development. The purpose of this report is designing an oil tankers’ shipyard facility. Basing the shipyard facility in Kuwait will have great economic rewards. The shipbuilding industry directly enhances the industrial chain in terms of new job and business opportunities as well as educational fields. Heavy Engineering Industries & Shipbuilding Co. K.S.C. (HEISCO) was chosen as a host due to benefits that will result from HEISCO’s existing infrastructure and expertise to reduce cost. The Facility Design methodology chosen has been used because it covers all aspects needed for the report. The oil tanker market is witnessing a shift from crude tankers to product tankers. Therefore the Panamax tanker (product tanker) was selected to be manufactured in the facility. The different departments needed in shipyards were identified based on studying different global shipyards. Technologies needed to build ships helped in the process design. It was noticed that ships are engineer to order. The new layout development of the proposed shipyard is currently in progress. A feasibility study will be conducted to ensure the success of the facility after developing the shipyard’s layout.Keywords: oil tankers, shipbuilding, shipyard, facility design, Kuwait
Procedia PDF Downloads 466214 Ideological Framing in Television News: The Case of “Settlement Process”
Authors: Mete Kazaz, Birol Gülnar
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Television news has gained a new dimension in terms of ideological approaches as a result of such factors as globalization, cross monopolization, presence of international companies etc. and certain strategies have been developed at the production, presentation and distribution stages of news. In this study, television news about a process called “settlement process” was investigated. In this framework, news about the settlement process on TV channels of TRT 1, ATV, FOX TV, NTV, HABERTÜRK, TRT HABER and STV was investigated using the content analysis method in terms of the strategies the ideology construction, attitude towards the party in power, attitude towards parties in opposition and attitude towards BDP (Peace and Democracy Part) and Imrali (the island where Abdullah Ocalan, head of PKK, is kept). First, the aforementioned TV channels were selected randomly from 3 groups in order to be able to reveal the representational capacity of commercial, news and public channels. The study covers 557 news items broadcast in the main news bulletins between the dates of 15 March 2013 and 15 March 2013. While there was a positive attitude towards the government in a sizable portion of the news about the settlement process (63.6%), the attitude of 25.3% of the news was impartial towards the government and 11.3% had a negative attitude. On the other hand, there was a negative attitude towards the Opposition in a considerable portion of the news about the settlement process (56.1%). The attitude of 35.9% of the news towards the Opposition was impartial whereas 8.0% had a positive attitude. While 34.9% of the news about the settlement process used the legitimization strategy from among the ideology construction strategies, 22.8% used the unification strategy, 15.7% the reification strategy, 15.6% fractional and 11% concealment/mystification strategy.Keywords: attitude, ideological framing, television news, social sciences
Procedia PDF Downloads 353213 Effect of Reynolds Number on Wall-normal Turbulence Intensity in a Smooth and Rough Open Channel Using both Outer and Inner Scaling
Authors: Md Abdullah Al Faruque, Ram Balachandar
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Sudden change of bed condition is frequent in open channel flow. Change of bed condition affects the turbulence characteristics in both streamwise and wall-normal direction. Understanding the turbulence intensity in open channel flow is of vital importance to the modeling of sediment transport and resuspension, bed formation, entrainment, and the exchange of energy and momentum. A comprehensive study was carried out to understand the extent of the effect of Reynolds number and bed roughness on different turbulence characteristics in an open channel flow. Four different bed conditions (impervious smooth bed, impervious continuous rough bed, pervious rough sand bed, and impervious distributed roughness) and two different Reynolds numbers were adopted for this cause. The effect of bed roughness on different turbulence characteristics is seen to be prevalent for most of the flow depth. Effect of Reynolds number on different turbulence characteristics is also evident for flow over different bed, but the extent varies on bed condition. Although the same sand grain is used to create the different rough bed conditions, the difference in turbulence characteristics is an indication that specific geometry of the roughness has an influence on turbulence characteristics. Roughness increases the contribution of the extreme turbulent events which produces very large instantaneous Reynolds shear stress and can potentially influence the sediment transport, resuspension of pollutant from bed and alter the nutrient composition, which eventually affect the sustainability of benthic organisms.Keywords: open channel flow, Reynolds Number, roughness, turbulence
Procedia PDF Downloads 400212 Properties of Epoxy Composite Reinforced with Amorphous and Crystalline Silica from Rice Husk
Authors: Norul Hisham Hamid, Amir Affan, Ummi Hani Abdullah, Paridah Md. Tahir, Khairul Akmal Azhar, Rahmat Nawai, W. B. H. Wan Sulwani Izzati
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The dimensional stability and static bending properties of epoxy composite reinforced with amorphous and crystalline silica were investigated. The amorphous and crystalline silica was obtained by the precipitation method from carbonisation process of the rice husk at a temperature of 600 °C and 1000 °C for 7 hours respectively. The epoxy resin was mixed with 5%, 10% and 15% concentrations of amorphous and crystalline silica. The mixture was stirred for 10 minutes and cured at 28 °C for 72 hours and oven dried at 80 °C for 72 hours. The scanning electron microscope image showed the silica sized of 10-30nm was obtained. The water absorption and thickness swelling of epoxy/amorphous silica composite was not significantly different with silica concentration ranged from 0.08% to 0.09% and 0.17% to 0.20% respectively. The maximum modulus of rupture (85 MPa) and modulus of elasticity (3284 MPa) were achieved for 10% silica concentration. For epoxy/crystalline silica composite; the water absorption and thickness swelling were also not significantly different with silica concentration, ranged from 0.08% to 0.11% and 0.16% to 0.18% respectively. The maximum modulus of rupture (47.9 MPa) and modulus of elasticity (2760 MPa) were achieved for 10% silica concentration. Overall, the water absorption and thickness swelling were almost identical for epoxy composite made from either amorphous or crystalline silica. The epoxy composite made from amorphous silica was stronger than crystalline silica.Keywords: epoxy, composite, dimensional stability, static bending, silica
Procedia PDF Downloads 215211 A Micro-Scale of Electromechanical System Micro-Sensor Resonator Based on UNO-Microcontroller for Low Magnetic Field Detection
Authors: Waddah Abdelbagi Talha, Mohammed Abdullah Elmaleeh, John Ojur Dennis
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This paper focuses on the simulation and implementation of a resonator micro-sensor for low magnetic field sensing based on a U-shaped cantilever and piezoresistive configuration, which works based on Lorentz force physical phenomena. The resonance frequency is an important parameter that depends upon the highest response and sensitivity through the frequency domain (frequency response) of any vibrated micro-scale of an electromechanical system (MEMS) device. And it is important to determine the direction of the detected magnetic field. The deflection of the cantilever is considered for vibrated mode with different frequencies in the range of (0 Hz to 7000 Hz); for the purpose of observing the frequency response. A simple electronic circuit-based polysilicon piezoresistors in Wheatstone's bridge configuration are used to transduce the response of the cantilever to electrical measurements at various voltages. Microcontroller-based Arduino program and PROTEUS electronic software are used to analyze the output signals from the sensor. The highest output voltage amplitude of about 4.7 mV is spotted at about 3 kHz of the frequency domain, indicating the highest sensitivity, which can be called resonant sensitivity. Based on the resonant frequency value, the mode of vibration is determined (up-down vibration), and based on that, the vector of the magnetic field is also determined.Keywords: resonant frequency, sensitivity, Wheatstone bridge, UNO-microcontroller
Procedia PDF Downloads 127210 A Sociolinguistic Investigation of Code-Switching Practices of ESL Students Outside EFL Classrooms
Authors: Shehroz Mukhtar, Maqsood Ahmed, Abdullah Mukhtar, Choudhry Shahid, Waqar Javaid
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Code switching is a common phenomenon, generally observed in multilingual communities across the globe. A critical look at code switching literature reveals that mostly code switching has been studied in classroom in learning and teaching context while code switching outside classroom in settings such as café, hostel and so on have been the least explored areas. Current research investigated the reasons for code switching in the interactive practices of students and their perceptions regarding the same outside the classroom settings. This paper is the study of the common practice that prevails in the Universities of Sialkot that bilinguals mix two languages when they speak in different class room situations. In Pakistani classrooms where Multilingual are in abundance i.e. they can speak two or more than two languages at the same time, the code switching or language combination is very common. The teachers of Sialkot switch from one language to another consciously or unconsciously while teaching English in the class rooms. This phenomenon has not been explored in the Sialkot’s teaching context. In Sialkot private educational institutes does not encourage code-switching whereas the public or government institutes use it frequently. The crux of this research is to investigate and identify the importance of code switching by taking its users in consideration. Survey research method and survey questionnaire will be used to get exact data from teachers and students. We will try to highlight the functions and importance of code switching in foreign language classrooms of Sialkot and will explore why this trend is emerging in Sialkot.Keywords: code switching, bilingual context, L1, L2
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