Search results for: five factor model of personality
Commenced in January 2007
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Paper Count: 20777

Search results for: five factor model of personality

10277 Effects of a Bacteria-Based Probiotic on Subpopulations of Peripheral Leukocytes and Their Interleukin mRNA Expression in Calves

Authors: Abdul Qadir Qadis, Satoru Goya, Minoru Yatsu, Yu-uki Yoshida, Toshihiro Ichijo, Shigeru Sato

Abstract:

Bacterial probiotics are known to modulate the gut-associated lymphoid and epithelial tissue response to enhance the activities of intestinal and systemic immune system in human and animals. In cattle, the immune-stimulatory effects of probiotics have been evaluated during intestinal disorders. To investigate the effects of probiotic on the function of peripheral blood mononuclear cells, eight healthy Holstein calves (10 ± 3 weeks) were assigned to a 4 × 2 experimental design. The probiotic, consisting of Lactobacillus plantarum, Enterococcus faecium and Clostridium butyricum, was administered orally at 3.0 g/100 kg body weight to calves once daily for 5 consecutive days. Calves given no probiotic served as the control. In the treatment group, increases in numbers of CD282+ monocytes, CD3+ T-cells and CD4+, CD8+ and WC1+ γδ T- cell subsets were noted on day 7 post-placement compared to pre-dose day and the control group. Expression of interleukin-6, interferon-gamma and tumor necrosis factor-alpha was elevated in peripheral leukocytes on days 7 and 14. These results suggest that peripheral blood leukocytes in healthy calves may be stimulated via the gastrointestinal microbiota, which was increased by the oral probiotic treatment. The 5-day repeated administration of a bacterial probiotic may enhance cellular immune function in weaned calves.

Keywords: bacterial-probiotic, calf, interleukin, leukocyte

Procedia PDF Downloads 647
10276 The Studies of Client Requirements in Home Stay: A Case Study of Thailand

Authors: Kanamon Suwantada

Abstract:

The purpose of this research is to understand customer’s expectations towards homestays and to establish the precise strategies to increase numbers of tourists for homestay business in Amphawa district, Samutsongkram, Thailand. The researcher aims to ensure that each host provides experiences to travelers who are looking for and determining new targets for homestay business in Amphawa as well as creating sustainable homestay using marketing strategies to increase customers. The methods allow interview and questionnaire to gain both overview data from the tourists and qualitative data from the homestay owner’s perspective to create a GAP analysis. The data was collected from 200 tourists, during 15th May - 30th July, 2011 from homestay in Amphawa Community. The questionnaires were divided into three sections: the demographic profile, customer information and influencing on purchasing position, and customer expectation towards homestay. The analysis, in fact, will be divided into two methods which are percentage and correlation analyses. The result of this research revealed that homestay had already provided customers with reasonable prices in good locations. Antithetically, activities that they offered still could not have met the customer’s requirements. Homestay providers should prepare additional activities such as village tour, local attraction tour, village daily life experiences, local ceremony participation, and interactive conversation with local people. Moreover, the results indicated that a price was the most important factor for choosing homestay.

Keywords: ecotourism, homestay, marketing, sufficiency economic philosophy

Procedia PDF Downloads 300
10275 Loading and Unloading Scheduling Problem in a Multiple-Multiple Logistics Network: Modelling and Solving

Authors: Yasin Tadayonrad

Abstract:

Most of the supply chain networks have many nodes starting from the suppliers’ side up to the customers’ side that each node sends/receives the raw materials/products from/to the other nodes. One of the major concerns in this kind of supply chain network is finding the best schedule for loading /unloading the shipments through the whole network by which all the constraints in the source and destination nodes are met and all the shipments are delivered on time. One of the main constraints in this problem is loading/unloading capacity in each source/ destination node at each time slot (e.g., per week/day/hour). Because of the different characteristics of different products/groups of products, the capacity of each node might differ based on each group of products. In most supply chain networks (especially in the Fast-moving consumer goods industry), there are different planners/planning teams working separately in different nodes to determine the loading/unloading timeslots in source/destination nodes to send/receive the shipments. In this paper, a mathematical problem has been proposed to find the best timeslots for loading/unloading the shipments minimizing the overall delays subject to respecting the capacity of loading/unloading of each node, the required delivery date of each shipment (considering the lead-times), and working-days of each node. This model was implemented on python and solved using Python-MIP on a sample data set. Finally, the idea of a heuristic algorithm has been proposed as a way of improving the solution method that helps to implement the model on larger data sets in real business cases, including more nodes and shipments.

Keywords: supply chain management, transportation, multiple-multiple network, timeslots management, mathematical modeling, mixed integer programming

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10274 Electronic Equipment Failure due to Corrosion

Authors: Yousaf Tariq

Abstract:

There are many reasons which are involved in electronic equipment failure i.e. temperature, humidity, dust, smoke etc. Corrosive gases are also one of the factor which may involve in failure of equipment. Sensitivity of electronic equipment increased when “lead-free” regulation enforced on manufacturers. In data center, equipment like hard disk, servers, printed circuit boards etc. have been exposed to gaseous contamination due to increase in sensitivity. There is a worldwide standard to protect electronic industrial electronic from corrosive gases. It is well known as “ANSI/ISA S71.04 – 1985 - Environmental Conditions for Control Systems: Airborne Contaminants. ASHRAE Technical Committee (TC) 9.9 members also recommended ISA standard in their whitepaper on Gaseous and Particulate Contamination Guideline for data centers. TC 9.9 members represented some of the major IT equipment manufacturers e.g. IBM, HP, Cisco etc. As per standard practices, first step is to monitor air quality in data center. If contamination level shows more than G1, it means that gas-phase air filtration is required other than dust/smoke air filtration. It is important that outside fresh air entering in data center should have pressurization/re-circulated process in order to absorb corrosive gases and to maintain level within specified limit. It is also important that air quality monitoring should be conducted once in a year. Temperature and humidity should also be monitored as per standard practices to maintain level within specified limit.

Keywords: corrosive gases, corrosion, electronic equipment failure, ASHRAE, hard disk

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10273 A Dual Spark Ignition Timing Influence for the High Power Aircraft Radial Engine Using a CFD Transient Modeling

Authors: Tytus Tulwin, Ksenia Siadkowska, Rafał Sochaczewski

Abstract:

A high power radial reciprocating engine is characterized by a large displacement volume of a combustion chamber. Choosing the right moment for ignition is important for a high performance or high reliability and ignition certainty. This work shows methods of simulating ignition process and its impact on engine parameters. For given conditions a flame speed is limited when a deflagration combustion takes place. Therefore, a larger length scale of the combustion chamber compared to a standard size automotive engine makes combustion take longer time to propagate. In order to speed up the mixture burn-up time the second spark is introduced. The transient Computational Fluid Dynamics model capable of simulating multicycle engine processes was developed. The CFD model consists of ECFM-3Z combustion and species transport models. A relative ignition timing difference for the both spark sources is constant. The temperature distribution on engine walls was calculated in the separate conjugate heat transfer simulation. The in-cylinder pressure validation was performed for take-off power flight conditions. The influence of ignition timing on parameters like in-cylinder temperature or rate of heat release was analyzed. The most advantageous spark timing for the highest power output was chosen. The conditions around the spark plug locations for the pre-ignition period were analyzed. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.

Keywords: CFD, combustion, ignition, simulation, timing

Procedia PDF Downloads 285
10272 Integrated Dynamic Analysis of Semi-Submersible Flap Type Concept

Authors: M. Rafiur Rahman, M. Mezbah Uddin, Mohammad Irfan Uddin, M. Moinul Islam

Abstract:

With a rapid development of offshore renewable energy industry, the research activities in regards of harnessing power from offshore wind and wave energy are increasing day by day. Integration of wind turbines and wave energy converters into one combined semi-submersible platform might be a cost-economy and beneficial option. In this paper, the coupled integrated dynamic analysis in the time domain (TD) of a simplified semi-submersible flap type concept (SFC) is accomplished via state-of-the-art numerical code referred as Simo-Riflex-Aerodyn (SRA). This concept is a combined platform consisting of a semi-submersible floater supporting a 5 MW horizontal axis wind turbine (WT) and three elliptical shaped flap type wave energy converters (WECs) on three pontoons. The main focus is to validate the numerical model of SFC with experimental results and perform the frequency domain (FD) and TD response analysis. The numerical analysis is performed using potential flow theory for hydrodynamics and blade element momentum (BEM) theory for aerodynamics. A variety of environmental conditions encompassing the functional & survival conditions for short-term sea (1-hour simulation) are tested to evaluate the sustainability of the SFC. The numerical analysis is performed in full scale. Finally, the time domain analysis of heave, pitch & surge motions is performed numerically using SRA and compared with the experimental results. Due to the simplification of the model, there are some discrepancies which are discussed in brief.

Keywords: coupled integrated dynamic analysis, SFC, time domain analysis, wave energy converters

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10271 Fuzzy Time Series- Markov Chain Method for Corn and Soybean Price Forecasting in North Carolina Markets

Authors: Selin Guney, Andres Riquelme

Abstract:

Among the main purposes of optimal and efficient forecasts of agricultural commodity prices is to guide the firms to advance the economic decision making process such as planning business operations and marketing decisions. Governments are also the beneficiaries and suppliers of agricultural price forecasts. They use this information to establish a proper agricultural policy, and hence, the forecasts affect social welfare and systematic errors in forecasts could lead to a misallocation of scarce resources. Various empirical approaches have been applied to forecast commodity prices that have used different methodologies. Most commonly-used approaches to forecast commodity sectors depend on classical time series models that assume values of the response variables are precise which is quite often not true in reality. Recently, this literature has mostly evolved to a consideration of fuzzy time series models that provide more flexibility in terms of the classical time series models assumptions such as stationarity, and large sample size requirement. Besides, fuzzy modeling approach allows decision making with estimated values under incomplete information or uncertainty. A number of fuzzy time series models have been developed and implemented over the last decades; however, most of them are not appropriate for forecasting repeated and nonconsecutive transitions in the data. The modeling scheme used in this paper eliminates this problem by introducing Markov modeling approach that takes into account both the repeated and nonconsecutive transitions. Also, the determination of length of interval is crucial in terms of the accuracy of forecasts. The problem of determining the length of interval arbitrarily is overcome and a methodology to determine the proper length of interval based on the distribution or mean of the first differences of series to improve forecast accuracy is proposed. The specific purpose of this paper is to propose and investigate the potential of a new forecasting model that integrates methodologies for determining the proper length of interval based on the distribution or mean of the first differences of series and Fuzzy Time Series- Markov Chain model. Moreover, the accuracy of the forecasting performance of proposed integrated model is compared to different univariate time series models and the superiority of proposed method over competing methods in respect of modelling and forecasting on the basis of forecast evaluation criteria is demonstrated. The application is to daily corn and soybean prices observed at three commercially important North Carolina markets; Candor, Cofield and Roaring River for corn and Fayetteville, Cofield and Greenville City for soybeans respectively. One main conclusion from this paper is that using fuzzy logic improves the forecast performance and accuracy; the effectiveness and potential benefits of the proposed model is confirmed with small selection criteria value such MAPE. The paper concludes with a discussion of the implications of integrating fuzzy logic and nonarbitrary determination of length of interval for the reliability and accuracy of price forecasts. The empirical results represent a significant contribution to our understanding of the applicability of fuzzy modeling in commodity price forecasts.

Keywords: commodity, forecast, fuzzy, Markov

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10270 Trends of Code-Mixing in a Bilingual Nigerian Child: An Investigation of a Three-Year-Old Child

Authors: Salamatu Sani

Abstract:

This study is an investigation of how code-mixing manifests in the language development of a Nigerian child, especially in the Hausa speaking environment. It is hinged on the fact that the environment influences the first language acquired by a child regardless of the cultural and/or linguistic background of the parents. The child under investigation has been subjected to close monitoring on her speech hitherto. It is a longitudinal study covering a period of twelve months (January 2018 to December 2018); that was when the subject was between twenty-four and thirty months of age. The speeches have been recorded by means of a tape recorder, video, and a diary. The study employs as a theoretical framework, emergentism, which is an eclectic of the behaviourist and the mentalist theories to the study of language development, for analysis. This is in agreement with the positions of Skinner and Watson. Sequel to this investigation, it was discovered the environment is a major factor that influences the exposure of a child to a language more than the other factors and that, if a child is exposed to more than one language, there is a great tendency for such a child to code-mix and code-switch in her speech production. The child under investigation, in spite of the linguistic background of her parents, speaks the Hausa Language much better than the other languages around her though with remarkable code-mixing with other languages around her such as English and Ebira languages. The study concludes that although a child is born with the innate ability to acquire a particular language, the environment plays a key role to trigger the innate ability and consequently, the child is exposed to the acquisition of the dominant language around her at a particular given time.

Keywords: bilingual, code-mixing, emergentism, environment, Hausa

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10269 Fault Detection and Diagnosis of Broken Bar Problem in Induction Motors Base Wavelet Analysis and EMD Method: Case Study of Mobarakeh Steel Company in Iran

Authors: M. Ahmadi, M. Kafil, H. Ebrahimi

Abstract:

Nowadays, induction motors have a significant role in industries. Condition monitoring (CM) of this equipment has gained a remarkable importance during recent years due to huge production losses, substantial imposed costs and increases in vulnerability, risk, and uncertainty levels. Motor current signature analysis (MCSA) is one of the most important techniques in CM. This method can be used for rotor broken bars detection. Signal processing methods such as Fast Fourier transformation (FFT), Wavelet transformation and Empirical Mode Decomposition (EMD) are used for analyzing MCSA output data. In this study, these signal processing methods are used for broken bar problem detection of Mobarakeh steel company induction motors. Based on wavelet transformation method, an index for fault detection, CF, is introduced which is the variation of maximum to the mean of wavelet transformation coefficients. We find that, in the broken bar condition, the amount of CF factor is greater than the healthy condition. Based on EMD method, the energy of intrinsic mode functions (IMF) is calculated and finds that when motor bars become broken the energy of IMFs increases.

Keywords: broken bar, condition monitoring, diagnostics, empirical mode decomposition, fourier transform, wavelet transform

Procedia PDF Downloads 139
10268 The Effect of Dry Matter Production Growth Rate, Temperature Rapeseed

Authors: Vadood Mobini, Mansoreh Agazadeh Shahrivar, Parvin Hashemi Gelenjkhanlo, Hassan Vazifah

Abstract:

Seed number is a function of dry matter accumulation, crop growth rate (CGR), photothermal quotient (PTQ) and temperature during a critical developmental period, which is around flowering in canola (Brassica napus L.). The objective of this experiment was to determine factors such as dry matter, CGR, temperature, and PTQ around flowering which affect seed number. The experiment was conducted at Agricultural Research Station of Gonbad, Iran, between 2005 and 2007. Two cultivars of canola (Hyola401 and RGS003), as subplots were grown at 5 sowing dates as main plots, spaced approximately 30 days apart, to obtain different environmental conditions during flowering. The experiment was arranged in two conditions, i.e., supplemental irrigation and rainfed. Seed number per unit area was a key factor for increasing seed yield. Late sowing dates made the critical period of flowering coincide with high temperatures, decreased days to the flowering, seed number per unit area and seed yield. Seed number was driven by the availability of carbohydrates around flowering. Seed number per unit area was maximized for the cultivars when exposed to the highest PTQ, and to the lowest temperature between the beginning of flowering to that of seed filling. The relationship of seed number with aboveground dry matter, CGR, temperature, and PTQ around flowering, over different environmental conditions, showed these variables were generally applicable to seed number determination.

Keywords: flowering, cultivar, seed filling, environmental conditions, seed yield

Procedia PDF Downloads 441
10267 Knowledge Transfer through Entrepreneurship: From Research at the University to the Consolidation of a Spin-off Company

Authors: Milica Lilic, Marina Rosales Martínez

Abstract:

Academic research cannot be oblivious to social problems and needs, so projects that have the capacity for transformation and impact should have the opportunity to go beyond the University circles and bring benefit to society. Apart from patents and R&D research contracts, this opportunity can be achieved through entrepreneurship as one of the most direct tools to turn knowledge into a tangible product. Thus, as an example of good practices, it is intended to analyze the case of an institutional entrepreneurship program carried out at the University of Seville, aimed at researchers interested in assessing the business opportunity of their research and expanding their knowledge on procedures for the commercialization of technologies used at academic projects. The program is based on three pillars: training, teamwork sessions and networking. The training includes aspects such as product-client fit, technical-scientific and economic-financial feasibility of a spin-off, institutional organization and decision making, public and private fundraising, and making the spin-off visible in the business world (social networks, key contacts, corporate image and ethical principles). On the other hand, the teamwork sessions are guided by a mentor and aimed at identifying research results with potential, clarifying financial needs and procedures to obtain the necessary resources for the consolidation of the spin-off. This part of the program is considered to be crucial in order for the participants to convert their academic findings into a business model. Finally, the networking part is oriented to workshops about the digital transformation of a project, the accurate communication of the product or service a spin-off offers to society and the development of transferable skills necessary for managing a business. This blended program results in the final stage where each team, through an elevator pitch format, presents their research turned into a business model to an experienced jury. The awarded teams get a starting capital for their enterprise and enjoy the opportunity of formally consolidating their spin-off company at the University. Studying the results of the program, it has been shown that many researchers have basic or no knowledge of entrepreneurship skills and different ways to turn their research results into a business model with a direct impact on society. Therefore, the described program has been used as an example to highlight the importance of knowledge transfer at the University and the role that this institution should have in providing the tools to promote entrepreneurship within it. Keeping in mind that the University is defined by three main activities (teaching, research and knowledge transfer), it is safe to conclude that the latter, and the entrepreneurship as an expression of it, is crucial in order for the other two to comply with their purpose.

Keywords: good practice, knowledge transfer, a spin-off company, university

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10266 Investigating Factors Influencing Online Formal and Informal Learning Satisfaction of College Students

Authors: Lei Zhang, Li Ji

Abstract:

Formal learning and informal learning represent two distinct learning styles: one is systematic and organized, another is causal and unstructured. Although there are many factors influencing online learning satisfaction, including self-regulation, self-efficacy, and interaction, factors influencing online formal learning and informal learning satisfaction may differ from each other. This paper investigated and compared influential factors of online formal and informal learning. Two questionnaires were created based on previous studies to explore factors influencing online formal learning and online informal learning satisfaction, respectively. A sample of 105 college students from different departments in a university located in the eastern part of China was selected to participate in this study. They all had an online learning experience and agreed to fill out questionnaires. Correlation analysis, variance analysis, and regression analysis were employed in this study. In addition, five participants were chosen for interviews. The study found that student-content, interaction, self-regulation, and self-efficacy related positively to both online formal learning and informal learning satisfaction. In addition, compared to online formal learning, student-content interaction in informal learning was the most influential factor for online learning satisfaction, perhaps that online informal learning was more goal-oriented and learners paid attention to the quality of content. In addition, results also revealed that interactions among students or teachers had little impact on online informal learning satisfaction. This study compared influential factors in online formal and informal learning satisfaction helped to add discussions to online learning satisfaction and contributed to further practices of online learning.

Keywords: learning satisfaction, formal learning, informal learning, online learning

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10265 Finite Element Analysis of a Glass Facades Supported by Pre-Tensioned Cable Trusses

Authors: Khair Al-Deen Bsisu, Osama Mahmoud Abuzeid

Abstract:

Significant technological advances have been achieved in the design and building construction of steel and glass in the last two decades. The metal glass support frame has been replaced by further sophisticated technological solutions, for example, the point fixed glazing systems. The minimization of the visual mass has reached extensive possibilities through the evolution of technology in glass production and the better understanding of the structural potential of glass itself, the technological development of bolted fixings, the introduction of the glazing support attachments of the glass suspension systems and the use for structural stabilization of cables that reduce to a minimum the amount of metal used. The variability of solutions of tension structures, allied to the difficulties related to geometric and material non-linear behavior, usually overrules the use of analytical solutions, letting numerical analysis as the only general approach to the design and analysis of tension structures. With the characteristics of low stiffness, lightweight, and small damping, tension structures are obviously geometrically nonlinear. In fact, analysis of cable truss is not only one of the most difficult nonlinear analyses because the analysis path may have rigid-body modes, but also a time consuming procedure. Non-linear theory allowing for large deflections is used. The flexibility of supporting members was observed to influence the stresses in the pane considerably in some cases. No other class of architectural structural systems is as dependent upon the use of digital computers as are tensile structures. Besides complexity, the process of design and analysis of tension structures presents a series of specificities, which usually lead to the use of special purpose programs, instead of general purpose programs (GPPs), such as ANSYS. In a special purpose program, part of the design know how is embedded in program routines. It is very probable that this type of program will be the option of the final user, in design offices. GPPs offer a range of types of analyses and modeling options. Besides, traditional GPPs are constantly being tested by a large number of users, and are updated according to their actual demands. This work discusses the use of ANSYS for the analysis and design of tension structures, such as cable truss structures under wind and gravity loadings. A model to describe the glass panels working in coordination with the cable truss was proposed. Under the proposed model, a FEM model of the glass panels working in coordination with the cable truss was established.

Keywords: Glass Construction material, Facades, Finite Element, Pre-Tensioned Cable Truss

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10264 Chinese Undergraduates’ Trust in And Usage of Machine Translation: A Survey

Authors: Bi Zhao

Abstract:

Neural network technology has greatly improved the output of machine translation in terms of both fluency and accuracy, which greatly increases its appeal for young users. The present exploratory study aims to find out how the Chinese undergraduates perceive and use machine translation in their daily life. A survey is conducted to collect data from 100 undergraduate students from multiple Chinese universities and with varied academic backgrounds, including arts, business, science, engineering, and medicine. The survey questions inquire about their use (including frequency, scenarios, purposes, and preferences) of and attitudes (including trust, quality assessment, justifications, and ethics) toward machine translation. Interviews and tasks of evaluating machine translation output are also employed in combination with the survey on a sample of selected respondents. The results indicate that Chinese undergraduate students use machine translation on a daily basis for a wide range of purposes in academic, communicative, and entertainment scenarios. Most of them have preferred machine translation tools, but the availability of machine translation tools within a certain scenario, such as the embedded machine translation tool on the webpage, is also the determining factor in their choice. The results also reveal that despite the reportedly limited trust in the accuracy of machine translation output, most students lack the ability to critically analyze and evaluate such output. Furthermore, the evidence is revealed of the inadequate awareness of ethical responsibility as machine translation users among Chinese undergraduate students.

Keywords: Chinese undergraduates, machine translation, trust, usage

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10263 Evaluation of Botanical Plant Powders against Zabrotes subfasciatus (Boheman) (Coleoptera: Bruchidae) in Stored Local Common Bean Varieties

Authors: Fikadu Kifle Hailegeorgis

Abstract:

Common bean is one of the most important sources of protein in Ethiopia and other developing countries. However, the Mexican bean weevil, Zabrotes subfasciatus (Boheman), is a major factor in the storage of common beans that causes losses. Studies were conducted to evaluate the efficacy of botanical powders of Jatropha curcas (L.), Neem/Azadrachta indica, and Parthenium hysterophorus (L) on local common bean varieties against Z subfasciatus at Melkassa Agriculture Research Center. Twenty local common bean varieties were evaluated twice against Z. Subfasciatus in a completely randomized design in three replications at the rate of 0.2g/250g of seed for each experiment. Malathion and untreated were used as standard checks. The result indicated that RAZ White and Round Yellow showed high resistance variety in experiments while Batu and Black showed high susceptible variety in experiments. Jatropha seed powder was the most effective against Z. subfasciatus. Parthenium seed powders and neem leaf powders also indicate promising results. Common beans treated with botanicals significantly (p<0.05) had a higher germination percentage than that of the untreated seed. In general, the results obtained indicated that using bean varieties (RAZ white and Round yellow) and botanicals (Jatropha) seed powder gave the best control of Z. subfasciatus.

Keywords: botanicals, malathion, resistant varieties, Z. subfasciatus

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10262 Protective Effect of Nigella sativa Oil and Its Neutral Lipid Fraction on Ethanol-Induced Hepatotoxicity in Rat Model

Authors: Asma Mosbah, Hanane Khither, Kamelia Mosbah, Noreddine Kacem Chaouche, Mustapha Benboubetra

Abstract:

In the present investigation, total oil (TO) and its neutral lipid fraction (NLF) extracted from the seed of the well know studied medicinal plant Nigella sativa were tested for their therapeutically effect on alcohol-induced liver injury in rat model. Male Albino rats were divided into five groups of eight animals each and fed a Lieber–DeCarli liquid diet containing 5% ethanol for experimental groups and dextran for control group, for a period of six weeks. Afterwards, rats received, orally, treatments with Nigella sativa extracts (TO, NLF) and N- acetylcysteine (NAC) as a positive control for four weeks. Activities of antioxidant enzymes; superoxide dismutase (SOD) and catalase (CAT), as well as malondialdehyde (MDA) and reduced glutathione (GSH). Biochemical parameters for kidney and liver functions, in treated and non treated rats, were evaluated throughout the time course of an experiment. Liver histological changes were taken into account. Enzymatic activities of both SOD and CAT increased significantly in rats treated with NLF and TO. While MDA level decreased in TO and NLF treated rats, GSH level increased significantly in TO and NLF treated rats. We noted equally a decrease in liver enzymes AST, ALT, and ALP. Microscopic observation of slides from the liver of ethanol treated rats showed a severe hepatotoxicity with lesions. Treatment with fractions leads to an improvement in liver lesions and a marked reduction in necrosis and infiltration. As a conclusion, both extracts of Nigella sativa seeds, TO and NLF, possess an important therapeutic protective potential against ethanol-induced hepatotoxicity in rats.

Keywords: alcohol-induced hepatotoxicity, antioxidant enzymes, Nigella sativa seeds, oil fractions

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10261 Numerical Calculation and Analysis of Fine Echo Characteristics of Underwater Hemispherical Cylindrical Shell

Authors: Hongjian Jia

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A finite-length cylindrical shell with a spherical cap is a typical engineering approximation model of actual underwater targets. The research on the omni-directional acoustic scattering characteristics of this target model can provide a favorable basis for the detection and identification of actual underwater targets. The elastic resonance characteristics of the target are the results of the comprehensive effect of the target length, shell-thickness ratio and materials. Under the conditions of different materials and geometric dimensions, the coincidence resonance characteristics of the target have obvious differences. Aiming at this problem, this paper obtains the omni-directional acoustic scattering field of the underwater hemispherical cylindrical shell by numerical calculation and studies the influence of target geometric parameters (length, shell-thickness ratio) and material parameters on the coincidence resonance characteristics of the target in turn. The study found that the formant interval is not a stable value and changes with the incident angle. Among them, the formant interval is less affected by the target length and shell-thickness ratio and is significantly affected by the material properties, which is an effective feature for classifying and identifying targets of different materials. The quadratic polynomial is utilized to fully fit the change relationship between the formant interval and the angle. The results show that the three fitting coefficients of the stainless steel and aluminum targets are significantly different, which can be used as an effective feature parameter to characterize the target materials.

Keywords: hemispherical cylindrical shell;, fine echo characteristics;, geometric and material parameters;, formant interval

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10260 Impact of Applying Bag House Filter Technology in Cement Industry on Ambient Air Quality - Case Study: Alexandria Cement Company

Authors: Haggag H. Mohamed, Ghatass F. Zekry, Shalaby A. Elsayed

Abstract:

Most sources of air pollution in Egypt are of anthropogenic origin. Alexandria Governorate is located at north of Egypt. The main contributing sectors of air pollution in Alexandria are industry, transportation and area source due to human activities. Alexandria includes more than 40% of the industrial activities in Egypt. Cement manufacture contributes a significant amount to the particulate pollution load. Alexandria Portland Cement Company (APCC) surrounding was selected to be the study area. APCC main kiln stack Total Suspended Particulate (TSP) continuous monitoring data was collected for assessment of dust emission control technology. Electro Static Precipitator (ESP) was fixed on the cement kiln since 2002. The collected data of TSP for first quarter of 2012 was compared to that one in first quarter of 2013 after installation of new bag house filter. In the present study, based on these monitoring data and metrological data a detailed air dispersion modeling investigation was carried out using the Industrial Source Complex Short Term model (ISC3-ST) to find out the impact of applying new bag house filter control technology on the neighborhood ambient air quality. The model results show a drastic reduction of the ambient TSP hourly average concentration from 44.94μg/m3 to 5.78μg/m3 which assures the huge positive impact on the ambient air quality by applying bag house filter technology on APCC cement kiln

Keywords: air pollution modeling, ambient air quality, baghouse filter, cement industry

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10259 A Bayesian Population Model to Estimate Reference Points of Bombay-Duck (Harpadon nehereus) in Bay of Bengal, Bangladesh Using CMSY and BSM

Authors: Ahmad Rabby

Abstract:

The demographic trend analyses of Bombay-duck from time series catch data using CMSY and BSM for the first time in Bangladesh. During 2000-2018, CMSY indicates average lowest production in 2000 and highest in 2018. This has been used in the estimation of prior biomass by the default rules. Possible 31030 viable trajectories for 3422 r-k pairs were found by the CMSY analysis and the final estimates for intrinsic rate of population increase (r) was 1.19 year-1 with 95% CL= 0.957-1.48 year-1. The carrying capacity(k) of Bombay-duck was 283×103 tons with 95% CL=173×103 - 464×103 tons and MSY was 84.3×103tons year-1, 95% CL=49.1×103-145×103 tons year-1. Results from Bayesian state-space implementation of the Schaefer production model (BSM) using catch & CPUE data, found catchabilitiy coefficient(q) was 1.63 ×10-6 from lcl=1.27×10-6 to ucl=2.10×10-6 and r= 1.06 year-1 with 95% CL= 0.727 - 1.55 year-1, k was 226×103 tons with 95% CL=170×103-301×103 tons and MSY was 60×103 tons year-1 with 95% CL=49.9 ×103- 72.2 ×103 tons year-1. Results for Bombay-duck fishery management based on BSM assessment from time series catch data illustrated that, Fmsy=0.531 with 95% CL =0.364 - 0.775 (if B > 1/2 Bmsy then Fmsy =0.5r); Fmsy=0.531 with 95% CL =0.364-0.775 (r and Fmsy are linearly reduced if B < 1/2Bmsy). Biomass in 2018 was 110×103 tons with 2.5th to 97.5th percentile=82.3-155×103 tons. Relative biomass (B/Bmsy) in last year was 0.972 from 2.5th percentile to 97.5th percentile=0.728 -1.37. Fishing mortality in last year was 0.738 with 2.5th-97.5th percentile=0.525-1.37. Exploitation F/Fmsy was 1.39, from 2.5th to 97.5th percentile it was 0.988 -1.86. The biological reference points of B/BMSY was smaller than 1.0, while F/FMSY was higher than 1.0 revealed an over-exploitation of the fishery, indicating that more conservative management strategies are required for Bombay-duck fishery.

Keywords: biological reference points, catchability coefficient, carrying capacity, intrinsic rate of population increase

Procedia PDF Downloads 116
10258 Correlation between Dynamic Knee Valgus with Isometric Hip External Rotators Strength during Single Leg Landing

Authors: Ahmed Fawzy, Khaled Ayad, Gh. M. Koura, W. Reda

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The excessive frontal plane motion of the lower extremity during sports activities is thought to be a contributing factor to many traumatic and overuse injuries of the knee joint, little is known about the biomechanical factors that contribute to this loading pattern. Objectives: The purpose of this study was to investigate if there is a relationship between hip external rotators isometric strength and the value of frontal plane projection angle (FPPA) during single leg landing tasks in normal male subjects. Methods: One hundred (male) subjects free from lower extremity injuries for at least six months ago participated in this study. Their mean age was (23.25 ± 2.88) years, mean weight was (74.76 ± 13.54) (Kg), mean height was (174.23 ± 6.56) (Cm). The knee frontal plane projection angle was measured by digital video camera using single leg landing task. Hip external rotators isometric strength were assessed by portable hand held dynamometer. Muscle strength had been normalized to the body weight to obtain more accurate measurements. Results: The results demonstrated that there was no significant relationship between hip external rotators isometric strength and the value of FPPA during single leg landing tasks in normal male subjects. Conclusion: It can be concluded that there is no relationship between hip external rotators isometric strength and the value of FPPA during functional activities in normal male subjects.

Keywords: 2-dimensional motion analysis, hip strength, kinematics, knee injuries

Procedia PDF Downloads 212
10257 Modeling Loads Applied to Main and Crank Bearings in the Compression-Ignition Two-Stroke Engine

Authors: Marcin Szlachetka, Mateusz Paszko, Grzegorz Baranski

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This paper discusses the AVL EXCITE Designer simulation research into loads applied to main and crank bearings in the compression-ignition two-stroke engine. There was created a model of engine lubrication system which covers the part of this system related to particular nodes of a bearing system, i.e. a connection of main bearings in an engine block with a crankshaft, a connection of crank pins with a connecting rod. The analysis focused on the load given as a distribution of hydrodynamic oil film pressure corresponding different values of radial internal clearance. There was also studied the impact of gas force on minimal oil film thickness in main and crank bearings versus crankshaft rotational speed. Our model calculates oil film parameters, an oil film pressure distribution, an oil temperature change and dimensions of bearings as well as an oil temperature distribution on surfaces of bearing seats. Accordingly, it was possible to select, for example, a correct clearance for each of the node bearings. The research was performed for several values of engine crankshaft speed ranging from 800 RPM to 4000 RPM. Bearing oil pressure was changed according to engine speed ranging between 1 bar and 5 bar and an oil temperature of 90°C. The main bearing clearances made initially for the calculation and research were: 0.015 mm, 0.025 mm, 0.035 mm, 0.05 mm, 0.1 mm. The oil used for the research corresponded the SAE 5W-40 classification. The paper presents the selected research results referring to certain specific operating points and bearing radial internal clearances. Acknowledgement: This work has been realized in the cooperation with The Construction Office of WSK ‘PZL-KALISZ’ S.A. and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.

Keywords: crank bearings, diesel engine, oil film, two-stroke engine

Procedia PDF Downloads 195
10256 New Managerialism and Organizational Commitment: Impact towards Employees' Work Performance in a Malaysian Public University

Authors: Kamarul Fairuz Hassim, Sharifah Fatimah Syed-Ahmad

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New managerialism has become the current trend in managing public sector which emphasizes on efficiency, effectiveness, and accountability. Public universities are not exempted from experiencing this new system. This study tries to explore the direct impact of new managerialism towards work performance of the employees in a public university in Malaysia and the indirect impact through a mediating factor – Organizational Commitment. Feedback were gathered from 204 respondents comprises of academics and non-academics managers in the University of Malaya using a 39 items, self-administered questionnaire. Respondents’ views were asked in the aspects of managerialism level of the university, their organizational commitment, and self-rated work performance level. The findings exhibit that there is a direct impact of new managerialism towards employees’ work performance in a positive way. This is contradicting to the established Hypotheses of this study. Furthermore, there is no significant finding on the role of all three components of organizational commitment – affective, normative, and continuance as the mediating factors in new managerialism approach that gave impact towards work performance. Consequently these insignificant found failed to corroborate the remaining six hypotheses in this study. On another note, findings gathered from this study show some contradiction to the original research conducted earlier by Smeenk et al. in 2009. Therefore, results obtained from this study do contribute to the existing pool of knowledge as previous studies on this topic are scarce especially in the Malaysia’s context.

Keywords: new managerialism, Malaysia public universities, organizational commitment, work performance

Procedia PDF Downloads 357
10255 Vibration Frequency Analysis of Sandwich Nano-Plate on Visco Pasternak Foundation by Using Modified Couple Stress Theory

Authors: Hamed Khani Arani, Mohammad Shariyat, Armaghan Mohammadian

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In this research, the free vibration of a rectangular sandwich nano-plate (SNP) made of three smart layers in the visco Pasternak foundation is studied. The core of the sandwich is a piezo magnetic nano-plate integrated with two layers of piezoelectric materials. First-order shear deformation plate theory is utilized to derive the motion equations by using Hamilton’s principle, piezoelectricity, and modified couple stress theory. Elastic medium is modeled by visco Pasternak foundation, where the damping coefficient effect is investigated on the stability of sandwich nano-plate. These equations are solved by the differential quadrature method (DQM), considering different boundary conditions. Results indicate the effect of various parameters such as aspect ratio, thickness ratio, shear correction factor, damping coefficient, and boundary conditions on the dimensionless frequency of sandwich nano-plate. The results are also compared by those available in the literature, and these findings can be used for automotive industry, communications equipment, active noise, stability, and vibration cancellation systems and utilized for designing the magnetostrictive actuator, motor, transducer and sensors in nano and micro smart structures.

Keywords: free vibration, modified couple stress theory, sandwich nano-plate, visco Pasternak foundation

Procedia PDF Downloads 126
10254 Powerful Media: Reflection of Professional Audience

Authors: Hamide Farshad, Mohammadreza Javidi Abdollah Zadeh Aval

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As a result of the growing penetration of the media into human life, a new role under the title of "audience" is defined in the social life .A kind of role which is dramatically changed since its formation. This article aims to define the audience position in the new media equations which is concluded to the transformation of the media role. By using the Library and Attributive method to study the history, the evolutionary outlook to the audience and the recognition of the audience and the media relation in the new media context is studied. It was perceived in past that public communication would result in receiving the audience. But after the emergence of the interactional media and transformation in the audience social life, a new kind of public communication is formed, and also the imaginary picture of the audience is replaced by the audience impact on the communication process. Part of this impact can be seen in the form of feedback which is one of the public communication elements. In public communication, the audience feedback is completely accepted. But in many cases, and along with the audience feedback, the media changes its direction; this direction shift is known as media feedback. At this state, the media and the audience are both doers and consistently change their positions in an interaction. With the greater number of the audience and the media, this process has taken a new role, and the role of this doer is sometimes taken by an audience while influencing another audience, or a media while influencing another media. In this article, this multiple public communication process is shown through representing a model under the title of ”The bilateral influence of the audience and the media.” Based on this model, the audience and the media power are not the two sides of a coin, and as a result, by accepting these two as the doers, the bilateral power of the audience and the media will be complementary to each other. Also more, the compatibility between the media and the audience is analyzed in the bilateral and interactional relation hypothesis, and by analyzing the action law hypothesis, the dos and don’ts of this role are defined, and media is obliged to know and accept them in order to be able to survive. They also have a determining role in the strategic studies of a media.

Keywords: audience, effect, media, interaction, action laws

Procedia PDF Downloads 470
10253 The State of Herb Medicine in Oriental Morocco: Cases of Debdou, Taourirt and Guerssif Districts

Authors: Himer Khalid, Alami Ilyass, Kharchoufa Loubna, Elachouri Mostafa

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It has been estimated by the World Health Organization that 80% of the world's population relies on traditional medicine to meet their daily health requirements. In Morocco reliance on such medicine is partly owing to the high cost of conventional medicine and the inaccessibility of modern health care facilities. There was high agreement in the use of plants as medicine in Oriental Morocco. Our objective is to evaluate the informant’s knowledge on medicinal plants by the local population and to document the uses of medicinal plants by this community, for the treatment of different illnesses. Using an ethnopharmacological approach, we collected information concerning the traditional medicinal knowledge and the medicinal plants used, by interviewing successfully 458 informants living in oriental Morocco (from Debdou, Taourirt, Guersif a,d Laayoune districts). The data were analyzed by statistical methods (Component Analysis “CA”, Factorial Analysis “FA”) and other methods such as through Informant’s Consensus Factor (ICF) and Use Value (UV). Our results indicate that, more than 60% of the population in these regions relies on medicinal plants for the treatment of different ailments with predominance of women consumers. 135 plant species belonging to 61 families were documented. These plants were used by the population for the treatment of a group of illness (about 14 principal ailments). We conclude that, in oriental Morocco, till now, the population has some traditional knowledge commonly used as medical tradition. These wealthy heritage needs conservation and evaluation.

Keywords: Morocco, medicinal plants, traditional knowledge, wealthy heritage

Procedia PDF Downloads 270
10252 An Artificial Intelligence Framework to Forecast Air Quality

Authors: Richard Ren

Abstract:

Air pollution is a serious danger to international well-being and economies - it will kill an estimated 7 million people every year, costing world economies $2.6 trillion by 2060 due to sick days, healthcare costs, and reduced productivity. In the United States alone, 60,000 premature deaths are caused by poor air quality. For this reason, there is a crucial need to develop effective methods to forecast air quality, which can mitigate air pollution’s detrimental public health effects and associated costs by helping people plan ahead and avoid exposure. The goal of this study is to propose an artificial intelligence framework for predicting future air quality based on timing variables (i.e. season, weekday/weekend), future weather forecasts, as well as past pollutant and air quality measurements. The proposed framework utilizes multiple machine learning algorithms (logistic regression, random forest, neural network) with different specifications and averages the results of the three top-performing models to eliminate inaccuracies, weaknesses, and biases from any one individual model. Over time, the proposed framework uses new data to self-adjust model parameters and increase prediction accuracy. To demonstrate its applicability, a prototype of this framework was created to forecast air quality in Los Angeles, California using datasets from the RP4 weather data repository and EPA pollutant measurement data. The results showed good agreement between the framework’s predictions and real-life observations, with an overall 92% model accuracy. The combined model is able to predict more accurately than any of the individual models, and it is able to reliably forecast season-based variations in air quality levels. Top air quality predictor variables were identified through the measurement of mean decrease in accuracy. This study proposed and demonstrated the efficacy of a comprehensive air quality prediction framework leveraging multiple machine learning algorithms to overcome individual algorithm shortcomings. Future enhancements should focus on expanding and testing a greater variety of modeling techniques within the proposed framework, testing the framework in different locations, and developing a platform to automatically publish future predictions in the form of a web or mobile application. Accurate predictions from this artificial intelligence framework can in turn be used to save and improve lives by allowing individuals to protect their health and allowing governments to implement effective pollution control measures.Air pollution is a serious danger to international wellbeing and economies - it will kill an estimated 7 million people every year, costing world economies $2.6 trillion by 2060 due to sick days, healthcare costs, and reduced productivity. In the United States alone, 60,000 premature deaths are caused by poor air quality. For this reason, there is a crucial need to develop effective methods to forecast air quality, which can mitigate air pollution’s detrimental public health effects and associated costs by helping people plan ahead and avoid exposure. The goal of this study is to propose an artificial intelligence framework for predicting future air quality based on timing variables (i.e. season, weekday/weekend), future weather forecasts, as well as past pollutant and air quality measurements. The proposed framework utilizes multiple machine learning algorithms (logistic regression, random forest, neural network) with different specifications and averages the results of the three top-performing models to eliminate inaccuracies, weaknesses, and biases from any one individual model. Over time, the proposed framework uses new data to self-adjust model parameters and increase prediction accuracy. To demonstrate its applicability, a prototype of this framework was created to forecast air quality in Los Angeles, California using datasets from the RP4 weather data repository and EPA pollutant measurement data. The results showed good agreement between the framework’s predictions and real-life observations, with an overall 92% model accuracy. The combined model is able to predict more accurately than any of the individual models, and it is able to reliably forecast season-based variations in air quality levels. Top air quality predictor variables were identified through the measurement of mean decrease in accuracy. This study proposed and demonstrated the efficacy of a comprehensive air quality prediction framework leveraging multiple machine learning algorithms to overcome individual algorithm shortcomings. Future enhancements should focus on expanding and testing a greater variety of modeling techniques within the proposed framework, testing the framework in different locations, and developing a platform to automatically publish future predictions in the form of a web or mobile application. Accurate predictions from this artificial intelligence framework can in turn be used to save and improve lives by allowing individuals to protect their health and allowing governments to implement effective pollution control measures.Air pollution is a serious danger to international wellbeing and economies - it will kill an estimated 7 million people every year, costing world economies $2.6 trillion by 2060 due to sick days, healthcare costs, and reduced productivity. In the United States alone, 60,000 premature deaths are caused by poor air quality. For this reason, there is a crucial need to develop effective methods to forecast air quality, which can mitigate air pollution’s detrimental public health effects and associated costs by helping people plan ahead and avoid exposure. The goal of this study is to propose an artificial intelligence framework for predicting future air quality based on timing variables (i.e. season, weekday/weekend), future weather forecasts, as well as past pollutant and air quality measurements. The proposed framework utilizes multiple machine learning algorithms (logistic regression, random forest, neural network) with different specifications and averages the results of the three top-performing models to eliminate inaccuracies, weaknesses, and biases from any one individual model. Over time, the proposed framework uses new data to self-adjust model parameters and increase prediction accuracy. To demonstrate its applicability, a prototype of this framework was created to forecast air quality in Los Angeles, California using datasets from the RP4 weather data repository and EPA pollutant measurement data. The results showed good agreement between the framework’s predictions and real-life observations, with an overall 92% model accuracy. The combined model is able to predict more accurately than any of the individual models, and it is able to reliably forecast season-based variations in air quality levels. Top air quality predictor variables were identified through the measurement of mean decrease in accuracy. This study proposed and demonstrated the efficacy of a comprehensive air quality prediction framework leveraging multiple machine learning algorithms to overcome individual algorithm shortcomings. Future enhancements should focus on expanding and testing a greater variety of modeling techniques within the proposed framework, testing the framework in different locations, and developing a platform to automatically publish future predictions in the form of a web or mobile application. Accurate predictions from this artificial intelligence framework can in turn be used to save and improve lives by allowing individuals to protect their health and allowing governments to implement effective pollution control measures.

Keywords: air quality prediction, air pollution, artificial intelligence, machine learning algorithms

Procedia PDF Downloads 106
10251 The Chemical Transport Mechanism of Emitter Micro-Particles in Tungsten Electrode: A Metallurgical Study

Authors: G. Singh, H.Schuster, U. Füssel

Abstract:

The stability of electric arc and durability of electrode tip used in Tungsten Inert Gas (TIG) welding demand a metallurgical study about the chemical transport mechanism of emitter oxide particles in tungsten electrode during its real welding conditions. The tungsten electrodes doped with emitter oxides of rare earth oxides such as La₂O₃, Th₂O₃, Y₂O₃, CeO₂ and ZrO₂ feature a comparatively lower work function than tungsten and thus have superior emission characteristics due to lesser surface temperature of the cathode. The local change in concentration of these emitter particles in tungsten electrode due to high temperature diffusion (chemical transport) can change its functional properties like electrode temperature, work function, electron emission, and stability of the electrode tip shape. The resulting increment in tip surface temperature results in the electrode material loss. It was also observed that the tungsten recrystallizes to large grains at high temperature. When the shape of grain boundaries are granular in shape, the intergranular diffusion of oxide emitter particles takes more time to reach the electrode surface. In the experimental work, the microstructure of the used electrode's tip surface will be studied by scanning electron microscope and reflective X-ray technique in order to gauge the extent of the diffusion and chemical reaction of emitter particles. Besides, a simulated model is proposed to explain the effect of oxide particles diffusion on the electrode’s microstructure, electron emission characteristics, and electrode tip erosion. This model suggests metallurgical modifications in tungsten electrode to enhance its erosion resistance.

Keywords: rare-earth emitter particles, temperature-dependent diffusion, TIG welding, Tungsten electrode

Procedia PDF Downloads 171
10250 The Development of E-Commerce in Mexico: An Econometric Analysis

Authors: Alma Lucero Ortiz, Mario Gomez

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Technological advances contribute to the well-being of humanity by allowing man to perform in a more efficient way. Technology offers tangible advantages to countries with the adoption of information technologies, communication, and the Internet in all social and productive sectors. The Internet is a networking infrastructure that allows the communication of people throughout the world, exceeding the limits of time and space. Nowadays the internet has changed the way of doing business leading to a digital economy. In this way, e-commerce has emerged as a commercial transaction conducted over the Internet. For this inquiry e-commerce is seen as a source of economic growth for the country. Thereby, these research aims to answer the research question, which are the main variables that have affected the development of e-commerce in Mexico. The research includes a period of study from 1990 to 2017. This inquiry aims to get insight on how the independent variables influence the e-commerce development. The independent variables are information infrastructure construction, urbanization level, economic level, technology level, human capital level, educational level, standards of living, and price index. The results suggest that the independent variables have an impact on development of the e-commerce in Mexico. The present study is carried out in five parts. After the introduction, in the second part, a literature review about the main qualitative and quantitative studies to measure the variables subject to the study is presented. After, an empirical study is applied through time series data, and to process the data an econometric model is performed. In the fourth part, the analysis and discussion of results are presented, and finally, some conclusions are included.

Keywords: digital economy, e-commerce, econometric model, economic growth, internet

Procedia PDF Downloads 221
10249 Predictions of Thermo-Hydrodynamic State for Single and Three Pads Gas Foil Bearings Operating at Steady-State Based on Multi-Physics Coupling Computer Aided Engineering Simulations

Authors: Tai Yuan Yu, Pei-Jen Wang

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Oil-free turbomachinery is considered one of the critical technologies for future green power generation systems as rotor machinery systems. Oil-free technology allows clean, compact, and maintenance-free working, and gas foil bearings, abbreviated as GFBs, are important for the technology. Since the first applications in the auxiliary power units and air cycle machines in the 1970s, obvious improvement has been created to the computational models for dynamic rotor behavior. However, many technical issues are still poorly understood or remain unsolved, and some of those are thermal management and the pattern of how pressure will be distributed in bearing clearance. This paper presents a three-dimensional, abbreviated as 3D, fluid-structure interaction model of single pad foil bearings and three pad foil bearings to predict bearing working behavior that researchers could compare characteristics of those. The coupling analysis model involves dynamic working characteristics applied to all the gas film and mechanical structures. Therefore, the elastic deformation of foil structure and the hydrodynamic pressure of gas film can both be calculated by a finite element method program. As a result, the temperature distribution pattern could also be iteratively solved by coupling analysis. In conclusion, the working fluid state in a gas film of various pad forms of bearings working characteristic at constant rotational speed for both can be solved for comparisons with the experimental results.

Keywords: fluid-structure interaction, multi-physics simulations, gas foil bearing, oil-free, transient thermo-hydrodynamic

Procedia PDF Downloads 155
10248 Student Feedback of a Major Curricular Reform Based on Course Integration and Continuous Assessment in Electrical Engineering

Authors: Heikki Valmu, Eero Kupila, Raisa Vartia

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A major curricular reform was implemented in Metropolia UAS in 2014. The teaching was to be based on larger course entities and collaborative pedagogy. The most thorough reform was conducted in the department of electrical engineering and automation technology. It has been already shown that the reform has been extremely successful with respect to student progression and drop-out rate. The improvement of the results has been much more significant in this department compared to the other engineering departments making only minor pedagogical changes. In the beginning of the spring term of 2017, a thorough student feedback project was conducted in the department. The study consisted of thirty questions about the implementation of the curriculum, the student workload and other matters related to student satisfaction. The reply rate was more than 40%. The students were divided to four different categories: first year students [cat.1] and students of all the three different majors [categories 2-4]. These categories were found valid since all the students have the same course structure in the first two semesters after which they may freely select the major. All staff members are divided into four teams respectively. The curriculum consists of consecutive 15 credit (ECTS) courses each taught by a group of teachers (3-5). There are to be no end exams and continuous assessment is to be employed. In 2014 the different teacher groups were encouraged to employ innovatively different assessment methods within the given specs. One of these methods has been since used in categories 1 and 2. These students have to complete a number of compulsory tasks each week to pass the course and the actual grade is defined by a smaller number of tests throughout the course. The tasks vary from homework assignments, reports and laboratory exercises to larger projects and the actual smaller tests are usually organized during the regular lecture hours. The teachers of the other two majors have been pedagogically more conservative. The student progression has been better in categories 1 and 2 compared to categories 3 and 4. One of the main goals of this survey was to analyze the reasons for the difference and the assessment methods in detail besides the general student satisfaction. The results show that in the categories following more strictly the specified assessment model much more versatile assessment methods are used and the basic spirit of the new pedagogy is followed. Also, the student satisfaction is significantly better in categories 1 and 2. It may be clearly stated that continuous assessment and teacher cooperation improve the learning outcomes, student progression as well as student satisfaction. Too much academic freedom seems to lead to worse results [cat 3 and 4]. A standardized assessment model is launched for all students in autumn 2017. This model is different from the one used so far in categories 1 and 2 allowing more flexibility to teacher groups, but it will force all the teacher groups to follow the general rules in order to improve the results and the student satisfaction further.

Keywords: continuous assessment, course integration, curricular reform, student feedback

Procedia PDF Downloads 192