Search results for: vibration testing

Authors: Louis Ngai Yuen Wong, Varun Maruvanchery

Abstract:

The Bukit Timah Granite, which is a major rock formation in Singapore, encompasses different rock types such as granite, adamellite, and granodiorite with various hybrid rocks. The present study focuses on the Central Singapore Granite found in the Mandai area. Even within this small aerial extent, lithological variations with respect to the composition, texture as well as the grain size have been recognized in this igneous body. Over the years, the research effort on the Bukit Timah Granite has been focused on achieving a better understanding of its engineering properties in association with civil engineering projects. To our best understanding, a few types of research attempted to systematically investigate the influence of grain size, mineral composition, texture etc. on the strength of Bukit Timah Granite rocks in a comprehensive manner. In typical local industry practices, the different lithological varieties are not differentiated, but all are grouped under Bukit Timah Granite during core logging and the subsequent determination of engineering properties. To address such a major gap in the local engineering geological practice, a preliminary study is conducted on the variations of uniaxial compressive strength (UCS) in seven distinctly different lithological varieties found in the Bukit Timah Granite. Other physical properties including Young’s modulus, P-wave velocity and dry density determined from laboratory testing will also be discussed. The study is supplemented by a petrographical thin section examination. In addition, the specimen failure mode is classified and further correlated with the lithological varieties by carefully observing the details of crack initiation, propagation and coalescence processes in the specimens undergoing loading tests using a high-speed camera. The outcome of this research, which is the first of its type in Singapore, will have a direct implication on the sampling and design practices in the field of civil engineering and particularly underground space development in Singapore.

Keywords: Bukit Timah Granite, lithological variety, thin section study, high speed video, failure mode

Procedia PDF Downloads 322

Authors: Prakash Parasivamurthy, Vivek Rama Das, Ravikant Talluri, Veena Jawali

Abstract:

India ranks among third in the production of coconut besides Philippines and Indonesia. About 92% of the total production in the country is contributed from four southern states especially, Kerala (45.22%), Tamil Nadu (26.56%), Karnataka (10.85%), and Andhra Pradesh (8.93%). Other states, such as Goa, Maharashtra, Odisha, West Bengal, and those in the northeast (Tripura and Assam) account for the remaining 8.44%. The use of coconut shell as coarse aggregate in concrete has never been a usual practice in the industry, particularly in areas where light weight concrete is required for non-load bearing walls, non-structural floors, and strip footings. The high cost of conventional building materials is a major factor affecting construction delivery in India. In India, where abundant agricultural and industrial wastes are discharged, these wastes can be used as potential material or replacement material in the construction industry. This will have double the advantages viz., reduction in the cost of construction material and also as a means of disposal of wastes. Therefore, an attempt has been made in this study to utilize the coconut shell (CS) as coarse aggregate in rigid pavement. The present study was initiated with the characterization of materials by the basic material testing. The casted moulds are cured and tests are conducted for hardened concrete. The procedure is continued with determination of fck (Characteristic strength), E (Modulus of Elasticity) and µ (Poisson Value) by the test results obtained. For the analytical studies, rigid pavement was modeled by the KEN PAVE software, finite element software developed specially for road pavements and simultaneously design of rigid pavement was carried out with Indian standards. Results show that physical properties of CSAC (Coconut Shell Aggregate Concrete) with 10% replacement gives better results. The flexural strength of CSAC is found to increase by 4.25% as compared to control concrete. About 13 % reduction in pavement thickness is observed using optimum coconut shell.

Keywords: coconut shell, rigid pavement, modulus of elasticity, poison ratio

Procedia PDF Downloads 237

Authors: Davut Disci

Abstract:

Objective: to measure the factors affecting expectations and intentions of using mobile phone in educational contexts by university students, using advanced equations and modeling techniques. Design and Methodology: According to the literature, Mobile Addiction, Parental Surveillance- Safety/Security, Social Relations, and Mobile Behavior are most used terms of defining mobile use of people. Therefore these variables are tried to be measured to find and estimate their effects on expectations and intentions of using mobile phone in educational context. 421 university students participated in this study and there are 229 Female and 192 Male students. For the purpose of examining the mobile behavior and educational expectations and intentions, a questionnaire is prepared and applied to the participants who had to answer all the questions online. Furthermore, responses to close-ended questions are analyzed by using The Statistical Package for Social Sciences(SPSS) software, reliabilities are measured by Cronbach’s Alpha analysis and hypothesis are examined via using Multiple Regression and Linear Regression analysis and the model is tested with Structural Equation Modeling(SEM) technique which is important for testing the model scientifically. Besides these responses, open-ended questions are taken into consideration. Results: When analyzing data gathered from close-ended questions, it is found that Mobile Addiction, Parental Surveillance, Social Relations and Frequency of Using Mobile Phone Applications are affecting the mobile behavior of the participants in different levels, helping them to use mobile phone in educational context. Moreover, as for open-ended questions, participants stated that they use many mobile applications in their learning environment in terms of contacting with friends, watching educational videos, finding course material via internet. They also agree in that mobile phone brings greater flexibility to their lives. According to the SEM results the model is not evaluated and it can be said that it may be improved to show in SEM besides in multiple regression. Conclusion: This study shows that the specified model can be used by educationalist, school authorities to improve their learning environment.

Keywords: education, mobile behavior, mobile learning, technology, Turkey

Procedia PDF Downloads 421

Authors: Davut Disci

Abstract:

Objective: to measure the factors affecting expectations and intentions of using mobile phone in educational contexts by university students, using advanced equations and modeling techniques. Design and Methodology: According to the literature, Mobile Addiction, Parental Surveillance-Safety/Security, Social Relations, and Mobile Behavior are most used terms of defining mobile use of people. Therefore, these variables are tried to be measured to find and estimate their effects on expectations and intentions of using mobile phone in educational context. 421 university students participated in this study and there are 229 Female and 192 Male students. For the purpose of examining the mobile behavior and educational expectations and intentions, a questionnaire is prepared and applied to the participants who had to answer all the questions online. Furthermore, responses to close-ended questions are analyzed by using The Statistical Package for Social Sciences(SPSS) software, reliabilities are measured by Cronbach’s Alpha analysis and hypothesis are examined via using Multiple Regression and Linear Regression analysis and the model is tested with Structural Equation Modeling (SEM) technique which is important for testing the model scientifically. Besides these responses, open-ended questions are taken into consideration. Results: When analyzing data gathered from close-ended questions, it is found that Mobile Addiction, Parental Surveillance, Social Relations and Frequency of Using Mobile Phone Applications are affecting the mobile behavior of the participants in different levels, helping them to use mobile phone in educational context. Moreover, as for open-ended questions, participants stated that they use many mobile applications in their learning environment in terms of contacting with friends, watching educational videos, finding course material via internet. They also agree in that mobile phone brings greater flexibility to their lives. According to the SEM results the model is not evaluated and it can be said that it may be improved to show in SEM besides in multiple regression. Conclusion: This study shows that the specified model can be used by educationalist, school authorities to improve their learning environment.

Keywords: learning technology, instructional technology, mobile learning, technology

Procedia PDF Downloads 452

Authors: Carie Cunningham, Krsiten Lynch

Abstract:

Despite a viewer’s thought that they may be paying attention, many times they are missing out on their surrounds-- a phenomenon referred to as inattentional blindness. Inattention blindness refers to the failure of an individual to orient their attention to a particular item in their visual field. This well-defined in the psychology literature. Similarly, this phenomenon has been evaluated in media types in advertising. In advertising, not comprehending/remembering items in one’s field of vision is known as banner blindness. On the other hand, banner blindness is a phenomenon that occurs when individuals habitually see a banner in a specific area on a webpage, and thus condition themselves to ignore those habitual areas. Another reason that individuals avoid these habitual areas (usually on the top or sides of a webpage) is due to the lack of personal relevance or pertinent information to the viewer. Banner blindness, while a web-based concept, may also relate this inattention blindness. This paper is proposing an analysis of the true similarities and differences between these concepts bridging the two dimensions of thinking together. Forty participants participated in an eye-tracking and post-survey experiment to test attention and memory measures in both a banner blindness and inattention blindness condition. The two conditions were conducted between subjects semi-randomized order. Half of participants were told to search through the content ignoring the advertising banners; the other half of participants were first told to search through the content ignoring the distractor icon. These groups were switched after 5 trials and then 5 more trials were completed. In review of the literature, sustainability communication was found to have many inconsistencies with message production and viewer awareness. For the purpose of this study, we used advertising materials as stimuli. Results suggest that there are gaps between the two concepts and that more research should be done testing these effects in a real world setting versus an online environment. This contributes to theory by exploring the overlapping concepts—inattention blindness and banner blindness and providing the advertising industry with support that viewers can still fall victim to ignoring items in their field of view even if not consciously, which will impact message development.

Keywords: attention, banner blindness, eye movement, inattention blindness

Procedia PDF Downloads 275

Authors: R. Meier, M. Pander

Abstract:

In accordance with the industry 4.0 concept, manufacturing process steps as well as the materials themselves are going to be more and more digitalized within the next years. The “digital twin” representing the simulated and measured dataset of the (semi-finished) product can be used to control and optimize the individual processing steps and help to reduce costs and expenditure of time in product development, manufacturing, and recycling. In the present work, two material characterization methods based on Lamb waves were evaluated and compared. For demonstration purpose, both methods were shown at a standard industrial product - copper ribbons, often used in photovoltaic modules as well as in high-current microelectronic devices. By numerical approximation of the Rayleigh-Lamb dispersion model on measured phase velocities second order elastic constants (Young’s modulus, Poisson’s ratio) were determined. Furthermore, the effective third order elastic constants were evaluated by applying elastic, “non-destructive”, mechanical stress on the samples. In this way, small microstructural variations due to mechanical preconditioning could be detected for the first time. Both methods were compared with respect to precision and inline application capabilities. Microstructure of the samples was systematically varied by mechanical loading and annealing. Changes in the elastic ultrasound transport properties were correlated with results from microstructural analysis and mechanical testing. In summary, monitoring the elastic material properties of plate-like structures using Lamb waves is valuable for inline and non-destructive material characterization and manufacturing process control. Second order elastic constants analysis is robust over wide environmental and sample conditions, whereas the effective third order elastic constants highly increase the sensitivity with respect to small microstructural changes. Both Lamb wave based characterization methods are fitting perfectly into the industry 4.0 concept.

Keywords: lamb waves, industry 4.0, process control, elasticity, acoustoelasticity, microstructure

Procedia PDF Downloads 227

Authors: Marjan Moradi Fard, Hossein Rassi, Masoud Houshmand

Abstract:

Aim: Breast cancer is one of the most common cancers affecting the morbidity and mortality of Iranian women. This disease is a result of collective alterations of oncogenes and tumor suppressor genes. Studies have produced conflicting results concerning the role of p53 codon 72 polymorphism (G>C) and miR-146a rs2910164 polymorphism (G>C) on the risk of several cancers; therefore, a research was performed to estimate the association between the p53 codon 72 polymorphism and miR-146a rs2910164 polymorphism in breast cancer. Methods and Materials: A total of 45 archival breast cancer samples from khatam hospital and 40 healthy samples were collected. Verification of each cancer reported in a relative was sought through the pathology reports of the hospital records. Then, DNA extracted from all samples by standard methods and p53 codon 72 polymorphism genotypes and miR-146a rs2910164 polymorphism genotypes were analyzed using multiplex PCR. The tubules, mitotic activity, necrosis, polymorphism and grade of breast cancer were staged by Nottingham histological grading and immunohistochemical staining of the sections from the paraffin wax embedded tissues for the expression of ER, PR and p53 was carried out using a standard method. Finally, data analysis was performed using the 7 version of the Epi Info(TM) 2012 software and test chi-square(x2) for trend. Results: Successful DNA extraction was assessed by PCR amplification of b-actin gene (99 bp). According to the results, p53 GG genotype and miR-146a rs2910164 CC genotype was significantly associated with increased risk of breast cancer in the study population. In this study, we established that tumors of p53 GG genotype and miR-146a rs2910164 CC genotype exhibited higher mitotic activity, higher polymorphism, lower necrosis, lower tubules, higher ER- and PR-negatives and lower TP53-positives than the other genotypes. Conclusion: The present study provided preliminary evidence that a p53 GG genotype may effect breast cancer risk in the study population, interacting synergistically with miR-146a rs2910164 CC genotype. Our results demonstrate that the testing of p53 codon 72 polymorphism genotypes and miR-146a rs2910164 polymorphism genotypes in combination with clinical parameters can serve as major risk factors in the early identification of breast cancers.

Keywords: breast cancer, p53 codon 72 polymorphism, miR-146a rs2910164 polymorphism, genotypes

Procedia PDF Downloads 336

Authors: Marinelle El-Khoury, Lina Bouhaya, Nivine Abbas, Hassan Sleiman

Abstract:

The road network in the north of Lebanon is a prime example of the lack of pavement design and execution in Lebanon.  These roads show major distresses and hence, should be tested and evaluated. The aim of this research is to investigate and determine the deficiencies in road surface design in Lebanon, and to propose an environmentally friendly asphalt mix design. This paper consists of several parts: (i) evaluating pavement performance and structural behavior, (ii) identifying the distresses using visual examination followed by laboratory tests, (iii) deciding the optimal solution where rehabilitation or reconstruction is required and finally, (iv) identifying a sustainable method, which uses recycled material in the proposed mix. The asphalt formula contains Reclaimed Asphalt Pavement (RAP) in the base course layer and in the asphalt layer. Visual inspection of the roads in Tripoli shows that these roads face a high level of distress severity. Consequently, the pavement should be reconstructed rather than simply rehabilitated. Coring was done to determine the pavement layer thickness. The results were compared to the American Association of State Highway and Transportation Officials (AASHTO) design methodology and showed that the existing asphalt thickness is lower than the required asphalt thickness. Prior to the pavement reconstruction, the road materials were tested according to the American Society for Testing and Materials (ASTM) specification to identify whether the materials are suitable. Accordingly, the ASTM tests that were performed on the base course are Sieve analysis, Atterberg limits, modified proctor, Los Angeles, and California Bearing Ratio (CBR) tests. Results show a CBR value higher than 70%. Hence, these aggregates could be used as a base course layer. The asphalt layer was also tested and the results of the Marshall flow and stability tests meet the ASTM specifications. In the last section, an environmentally friendly mix was proposed. An optimal RAP percentage of 30%, which produced a well graded base course and asphalt mix, was determined through a series of trials.

Keywords: asphalt mix, reclaimed asphalt pavement, California bearing ratio, sustainability

Procedia PDF Downloads 130

Authors: Egoitz Aldanondo, Ekaitz Arruti, Amaia Iturrioz, Ivan Huarte, Fidel Zubiri

Abstract:

Manufacturing aeronautic structures joining extruded profiles or stringers to sheets or skins of aluminium is a typical manufacturing procedure in aeronautic structures. Although riveting is the conventional manufacturing technology to produce such joints, the Friction Stir Welding (FSW) and Laser Beam Welding (LBW) technologies have also demonstrated their potential for this kind of applications. Therefore, FSW and LBW technologies have the potential to continue their development as manufacturing processes for aeronautic structures showing benefits such as time-saving, light-weighting and overall cost reduction. In addition to that, new aluminium-lithium based alloy developments represent great opportunities for advanced aeronautic structure manufacturing with potential benefits such as lightweight construction or improved corrosion resistance. This work presents the main approaches by FSW and LBW to develop those technologies to produce stiffened panel structures such as fuselage by stringer-skin joints and using innovative aluminium-lithium alloys. Initial welding tests were performed in AA2198-T3S aluminium alloys for LBW technology and with AA2198-T851 for FSW. Later tests for both FSW and LBW have been carried out using AA2099-T83 alloy extrusions as stringers and AA2060-T8E30 as skin materials. The weld quality and properties have been examined by metallographic analysis and mechanical testing, including shear tensile tests and pull-out tests. The analysis of the results have shown the relationships between processing conditions, micro-macrostructural properties and the mechanical strength of the welded joints. The effects produced in the different alloys investigated have been observed and particular weld formation mechanics have been studied for each material and welding technology. Therefore, relationships between welding conditions and the obtained weld properties for each material combination and welding technology will be discussed in this presentation.

Keywords: AA2060-T8E30, AA2099-T83, AA2198-T3S, AA2198-T851, friction stir welding, laser beam welding

Procedia PDF Downloads 199

Authors: Hamza A. Pantami, Khozizah Shaari, Intan S. Ismail, Chong C. Min

Abstract:

Introduction: Tilapia is the second-highest harvested freshwater fish species in Malaysia, available in almost all fish farms and markets. Unfortunately, tilapia culture in Malaysia is highly affected by Aeromonas hydrophila and Streptococcus agalactiae, which affect the production rate and consequently pose a direct negative economic impact. Reliance on drugs to control or reduce bacterial infections has been led to contamination of water bodies and development of drug resistance, as well as gave rise to toxicity issues in downstream fish products. Resorting to vaccines have helped curb the problem to a certain extent, but a more effective solution is still required. Using microalgae-based feed to enhance the fish immunity against bacterial infection offers a promising alternative. Objectives: This study aims to evaluate the efficacy of Chlorella vulgaris at lower percentage incorporation in feeds for an immune boost of tilapia in a shorter time. Methods: The study was in two phases. The safety concentration studies at 500 mg/kg-1 and the administration of cultured C. vulgaris biomass via incorporation into fish feed for five different groups in three weeks. Group 1 was the control (0% incorporation), whereas group 2, 3, 4 and 5 received 0.625%, 1.25%, 2.5% and 5% incorporation respectively. The parameters evaluated were the blood profile, serum lysozyme activity (SLA), serum bactericidal activity (SBA), phagocytosis activity (PA), respiratory burst activity (RBA), and lymphoproliferation activity (LPA). The data were analyzed via ANOVA using SPSS (version 16). Further testing was done using Tukey’s test. All tests were performed at the 95% confidence interval (p < 0.05). Results: There were no toxic signs in tilapia fish at 500 mg/kg-1. Treated groups showed significantly better immune parameters compared to the control group (p < 0.05). Conclusions: C. vulgaris crude biomass in a fish meal at a lower incorporation level of 5% can increase specific and non-specific immunity in tilapia fish in a shorter time duration.

Keywords: Chlorella vulgaris, hematology profile, immune boost, lymphoproliferation

Procedia PDF Downloads 110

Authors: Ankit Khurana

Abstract:

The sufficient heat storage capacity or ability to dissipate heat is the most decisive parameter to have an effective and efficient functioning of Friction-based Brake Disc systems. The primary aim of the research was to analyse the effect of multiple coatings on lightweight disk rotors surface which not only alleviates the mass of vehicle & also, augments heat transfer. This research is projected to aid the automobile fraternity with an enunciated view over the thermal aspects in a braking system. The results of the project indicate that with the advent of modern coating technologies a brake system’s thermal curtailments can be removed and together with forced convection, heat transfer processes can see a drastic improvement leading to increased lifetime of the brake rotor. Other advantages of modifying the surface of a lightweight rotor substrate will be to reduce the overall weight of the vehicle, decrease the risk of thermal brake failure (brake fade and fluid vaporization), longer component life, as well as lower noise and vibration characteristics. A mathematical model was constructed in MATLAB which encompassing the various thermal characteristics of the proposed coatings and substrate materials required to approximate the heat flux values in a free and forced convection environment; resembling to a real-time braking phenomenon which could easily be modelled into a full cum scaled version of the alloy brake rotor part in ABAQUS. The finite element of a brake rotor was modelled in a constrained environment such that the nodal temperature between the contact surfaces of the coatings and substrate (Wrought Aluminum alloy) resemble an amalgamated solid brake rotor element. The initial results obtained were for a Plasma Electrolytic Oxidized (PEO) substrate wherein the Aluminum alloy gets a hard ceramic oxide layer grown on its transitional phase. The rotor was modelled and then evaluated in real-time for a constant ‘g’ braking event (based upon the mathematical heat flux input and convective surroundings), which reflected the necessity to deposit a conducting coat (sacrificial) above the PEO layer in order to inhibit thermal degradation of the barrier coating prematurely. Taguchi study was then used to bring out certain critical factors which may influence the maximum operating temperature of a multi-coated brake disc by simulating brake tests: a) an Alpine descent lasting 50 seconds; b) an Autobahn stop lasting 3.53 seconds; c) a Six–high speed repeated stop in accordance to FMVSS 135 lasting 46.25 seconds. Thermal Barrier coating thickness and Vane heat transfer coefficient were the two most influential factors and owing to their design and manufacturing constraints a final optimized model was obtained which survived the 6-high speed stop test as per the FMVSS -135 specifications. The simulation data highlighted the merits for preferring Wrought Aluminum alloy 7068 over Grey Cast Iron and Aluminum Metal Matrix Composite in coherence with the multiple coating depositions.

Keywords: lightweight brakes, surface modification, simulated braking, PEO, aluminum

Procedia PDF Downloads 408

Authors: Jorge Rodriguez-Guerra, Carlos Calleja, Aron Pujana, Iker Elorza, Ana Maria Macarulla

Abstract:

Society demands more reliable manufacturing processes capable of producing high quality products in shorter production cycles. New control algorithms have been studied to satisfy this paradigm, in which Fault-Tolerant Control (FTC) plays a significant role. It is suitable to detect, isolate and adapt a system when a harmful or faulty situation appears. In this paper, a general overview about FTC characteristics are exposed; highlighting the properties a system must ensure to be considered faultless. In addition, a research to identify which are the main FTC techniques and a classification based on their characteristics is presented in two main groups: Active Fault-Tolerant Controllers (AFTCs) and Passive Fault-Tolerant Controllers (PFTCs). AFTC encompasses the techniques capable of re-configuring the process control algorithm after the fault has been detected, while PFTC comprehends the algorithms robust enough to bypass the fault without further modifications. The mentioned re-configuration requires two stages, one focused on detection, isolation and identification of the fault source and the other one in charge of re-designing the control algorithm by two approaches: fault accommodation and control re-design. From the algorithms studied, one has been selected and applied to a case study based on an industrial hydraulic-press. The developed model has been embedded under a real-time validation platform, which allows testing the FTC algorithms and analyse how the system will respond when a fault arises in similar conditions as a machine will have on factory. One AFTC approach has been picked up as the methodology the system will follow in the fault recovery process. In a first instance, the fault will be detected, isolated and identified by means of a neural network. In a second instance, the control algorithm will be re-configured to overcome the fault and continue working without human interaction.

Keywords: fault-tolerant control, electro-hydraulic actuator, fault detection and isolation, control re-design, real-time

Procedia PDF Downloads 177

Authors: A. Q. Sobia, M. S. Hamidah, I. Azmi, S. F. A. Rafeeqi

Abstract:

Fibre-reinforced polymer (FRP) strengthened reinforced concrete (RC) structures are susceptible to intense deterioration when exposed to elevated temperatures, particularly in the incident of fire. FRP has the tendency to lose bond with the substrate due to the low glass transition temperature of epoxy; the key component of FRP matrix.  In the past few decades, various types of high performance cementitious composites (HPCC) were explored for the protection of RC structural members against elevated temperature. However, there is an inadequate information on the influence of elevated temperature on the ultra high performance fibre-reinforced cementitious composites (UHPFRCC) containing ground granulated blast furnace slag (GGBS) as a replacement of high alumina cement (HAC) in conjunction with hybrid fibres (basalt and polypropylene fibres), which could be a prospective fire resisting material for the structural components. The influence of elevated temperatures on the compressive as well as flexural strength of UHPFRCC, made of HAC-GGBS and hybrid fibres, were examined in this study. Besides control sample (without fibres), three other samples, containing 0.5%, 1% and 1.5% of basalt fibres by total weight of mix and 1 kg/m³ of polypropylene fibres, were prepared and tested. Another mix was also prepared with only 1 kg/m³ of polypropylene fibres. Each of the samples were retained at ambient temperature as well as exposed to 400, 700 and 1000 °C followed by testing after 28 and 56 days of conventional curing. Investigation of results disclosed that the use of hybrid fibres significantly helped to improve the ambient temperature compressive and flexural strength of UHPFRCC, which was found to be 80 and 14.3 MPa respectively. However, the optimum residual compressive strength was marked by UHPFRCC-CP (with polypropylene fibres only), equally after both curing days (28 and 56 days), i.e. 41%. In addition, the utmost residual flexural strength, after 28 and 56 days of curing, was marked by UHPFRCC– CP and UHPFRCC– CB2 (1 kg/m³ of PP fibres + 1% of basalt fibres) i.e. 39% and 48.5% respectively.

Keywords: fibre reinforced polymer materials (FRP), ground granulated blast furnace slag (GGBS), high-alumina cement, hybrid, fibres

Procedia PDF Downloads 287

Authors: Ayse Inel Manav, Nuray Simsek

Abstract:

The number of people with dementia and the problems that are experienced by these people are increasing along with aging world population. This study was carried out to assess the effects of reminiscence therapy using internet videos on the cognitive condition and apathy levels of elderly people who had mild dementia and lived in nursing homes. This randomly controlled experimental study was conducted between 25 May-25 August 2016 in the nursing home, elderly care and rehabilitation centers in Adana and Seyhan, Turkey. A total of 32 individuals participated in this study, 16 in the experimental group and 16 in the control group. Data were collected using a personal information form developed on the basis of the published literature, the Standardized Mini Mental Test (SMMT) and the Apathy Rating Scale (ARS). The Clinical Research Ethics Committee's approval, written institutional permission, and the written consent of the participants were obtained before data collection. The individuals in the experimental group received reminiscence therapy using internet videos for 60 minutes one day a week for three months. During the same period, 25-30 minutes of unstructured interviews on subjects unrelated to reminiscence were carried out with individuals in the control group. The SMMT and ARS were administered before the applications in the experimental group and at the end of the third month. The collected data were analyzed using descriptive statistics (means, standard deviations, and frequencies) as well as Student's t-test, the Mann-Whitney U-test, and Wilcoxon's signed ranks test. In this study, the total SMMT post-test scores of the experimental group were higher than those of the control group (p = 0.001; p < 0.01). There was a difference between experimental and control groups' total SMMT post-test scores (p = 0.001; p < 0.01). The experimental group's ARS total post-test scores were higher than those of the control group (p = 0.001; p < 0.01). This study found that group reminiscence therapy using internet videos improved the cognitive functions and apathy levels of elderly individuals with mild dementia.

Keywords: apaty, cognitive testing, dementia, elderly, reminisence threapy

Procedia PDF Downloads 197

Authors: Niaz Gharavi, Hexin Zhang

Abstract:

In the structural timber design, the shear modulus of the timber beam is an important factor that needs to be determined accurately. According to BS EN 408, shear modulus can be determined using torsion test or shear field test method. Although torsion test creates pure shear status in the beam, it does not represent the real-life situation when the beam is in the service. On the other hand, shear field test method creates similar loading situation as in reality. The latter method is based on shear distortion measurement of the beam at the zone with the constant transverse load in the standardized four-point bending test as indicated in BS EN 408. Current testing practice code advised using two metallic arms act as an instrument to measure the diagonal displacement of the constructing square. Timber is not a homogenous material, but a heterogeneous and this characteristic makes timber to undergo a non-uniform deformation. Therefore, the dimensions and the location of the constructing square in the area with the constant transverse force might alter the shear modulus determination. This study aimed to investigate the impact of the shape, size, and location of the square in the shear field test method. A binocular stereo vision system was developed to capture the 3D displacement of a grid of target points. This approach is an accurate and non-contact method to extract the 3D coordination of targeted object using two cameras. Two group of three glue laminated beams were produced and tested by the mean of four-point bending test according to BS EN 408. Group one constructed using two materials, laminated bamboo lumber and structurally graded C24 timber and group two consisted only structurally graded C24 timber. Analysis of Variance (ANOVA) was performed on the acquired data to evaluate the significance of size and location of the square in the determination of shear modulus of the beam. The results have shown that the size of the square is an affecting factor in shear modulus determination. However, the location of the square in the area with the constant shear force does not affect the shear modulus.

Keywords: shear field test method, BS EN 408, timber shear modulus, photogrammetry approach

Procedia PDF Downloads 212

Authors: Anna Curtin, Matthew Thibodeau, Heather Buckley

Abstract:

Water scarcity is characterized by a lack of access to clean and affordable drinking water, as well as water for hygienic and economic needs. The amount of people effected by water scarcity is expected to increase in the coming years due to climate change, population growth, and pollution, amongst other things. In response, scientists are pursuing cost effective drinking water treatment methods, often with a focus on alternative water sources. Desalination of seawater via reverse osmosis is one promising alternative method. Desalination of seawater via reverse osmosis, however, is limited significantly by biofouling of the filtration membrane. Biofouling is the buildup of microorganisms in a biofilm at the water-membrane interface. It clogs the membrane, decreasing the efficiency of filtration, consequently increasing operational and maintenance costs. Although effective, existing chemical treatment methods can damage the membrane, decreasing the lifespan of the membrane; create antibiotic resistance; and cause harm to humans and the environment if they pass through the membrane into the permeate. The current project focuses on applying safer preservatives used in home and personal care products to RO membranes to investigate the biofouling treatment efficacy. Currently, many of these safer preservatives have only been tested on cells in planktonic phase in suspension cultures, not on cells in biofilms. The results of suspension culture tests are not applicable to biofouling scenarios because organisms in planktonic phase in suspension cultures exhibit different morphological, chemical, and metabolic characteristics than those in a biofilm. Testing antifoulant efficacy of safer preservatives on biofilms will provide more applicable results to biofouling on RO membranes. To do this, biofilms will be grown on 96-well-plates and minimum inhibitory concentrations (MIC90) and log-reductions will be calculated for various safer preservatives. Results from these tests will be used to guide doses for tests of safer preservatives in a bench-scale RO system.

Keywords: reverse osmosis, biofouling, preservatives, antimicrobial, safer alternative, green chemistry

Procedia PDF Downloads 144

Authors: Fengxia Li, Lufeng Zhang, Haibo Wang

Abstract:

The tight sandstone gas reservoir in the Xujiahe Formation of the Sichuan Basin has huge reserves, but its utilization rate is low. Fracturing and stimulation are indispensable technologies to unlock their potential and achieve commercial exploitation. Slickwater is the most widely used fracturing fluid system in the fracturing and renovation of tight reservoirs. However, its viscosity is low, its sand-carrying performance is poor, and the risk of sand blockage is high. Increasing the sand carrying capacity by increasing the displacement will increase the frictional resistance of the pipe string, affecting the resistance reduction performance. The variable viscosity slickwater can flexibly switch between different viscosities in real-time online, effectively overcoming problems such as sand carrying and resistance reduction. Based on a self-developed indoor loop friction testing system, a visualization device for proppant transport, and a HAAKE MARS III rheometer, a comprehensive evaluation was conducted on the performance of variable viscosity slickwater, including resistance reduction, rheology, and sand carrying. The indoor experimental results show that: 1. by changing the concentration of drag-reducing agents, the viscosity of the slippery water can be changed between 2~30mPa. s; 2. the drag reduction rate of the variable viscosity slickwater is above 80%, and the shear rate will not reduce the drag reduction rate of the liquid; under indoor experimental conditions, 15mPa. s of variable viscosity and slickwater can basically achieve effective carrying and uniform placement of proppant. The layered fracturing effect of the JiangX well in the dense sandstone of the Xujiahe Formation shows that the drag reduction rate of the variable viscosity slickwater is 80.42%, and the daily production of the single layer after fracturing is over 50000 cubic meters. This study provides theoretical support and on-site experience for promoting the application of variable viscosity slickwater in tight sandstone gas reservoirs.

Keywords: slickwater, hydraulic fracturing, dynamic sand laying, drag reduction rate, rheological properties

Procedia PDF Downloads 75

Authors: Georgios Koronis, Arlindo Silva

Abstract:

This study seeks to understand the mechanical behavior of a natural fiber reinforced composite (epoxy/flax) in more depth, utilizing both experimental and numerical methods. It is attempted to identify relationships between the design parameters and the product performance, understand the effect of noise factors and reduce process variations. Optimization of the mechanical performance of manufactured goods has recently been implemented by numerous studies for green composites. However, these studies are limited and have explored in principal mass production processes. It is expected here to discover knowledge about composite’s manufacturing that can be used to design artifacts that are of low batch and tailored to niche markets. The goal is to reach greater consistency in the performance and further understand which factors play significant roles in obtaining the best mechanical performance. A prediction of response function (in various operating conditions) of the process is modeled by the DoE. Normally, a full factorial designed experiment is required and consists of all possible combinations of levels for all factors. An analytical assessment is possible though with just a fraction of the full factorial experiment. The outline of the research approach will comprise of evaluating the influence that these variables have and how they affect the composite mechanical behavior. The coupons will be fabricated by the vacuum infusion process defined by three process parameters: flow rate, injection point position and fiber treatment. Each process parameter is studied at 2-levels along with their interactions. Moreover, the tensile and flexural properties will be obtained through mechanical testing to discover the key process parameters. In this setting, an experimental phase will be followed in which a number of fabricated coupons will be tested to allow for a validation of the design of the experiment’s setup. Finally, the results are validated by performing the optimum set of in a final set of experiments as indicated by the DoE. It is expected that after a good agreement between the predicted and the verification experimental values, the optimal processing parameter of the biocomposite lamina will be effectively determined.

Keywords: design of experiments, flax fabrics, mechanical performance, natural fiber reinforced composites

Procedia PDF Downloads 204

Authors: Shanza Akram, Samir Salah, Imran Saleem, Ashraf Alzaabi, Jassim Abdou

Abstract:

Introduction: 300 million people worldwide are affected by asthma .In UAE, prevalence is around 10% (900,000 people).Patients with persistent symptoms despite using high dose ICS plus a second controller +/- OCS are considered to have severe asthma. Omalizumab (Xolaire) an IgE monoclonal antibody is approved as add on therapy for severe allergic asthma. Objective: To determine the efficacy of omalizumab based on clinical outcomes in our cohort of patient pre and post 52 weeks of treatment to assess safety and tolerability of treatment. Methods: Medical records of patients receiving omalizumab therapy for asthma at ZMH ,Abu Dhabi were retrospectively analyzed.Patients fulfilling the criteria of severe allergic asthma as per GINA guidelines were included. Asthma control over 12 months prior to and 12 months after commencement of omalizumab therapy was analysed by taking into account the number of exacerbations and hospitalizations in addition to maintenance of medication dosages, need for rescue reliever therapy and pulmonary function testing. Results: Total cohort of 21 patient (5 females), average age 41 years and av length of therapy 22 months were included. Seven patients (total 11/52%) managed to stop steroids on treatment while four were able to decrease the dosage. Mean exacerbation rate decreased from five/ year pre treatment to 1.36 while on treatment. Number of hospitalizations decreased from mean of two per year to 0.9 per year. Rescue reliever inhaler usage decreased from mean of 40 puffs to 15 puffs per week. 2 patients discontinued therapy, 1 due to lack of benefit (2 doses) and 2nd due to severe persistent side effects including local irritation, severe limb and joint pains after 6 months. Conclusion: Treatment with omalizumab showed effect in terms of reduced number of exacerbations, maintenance therapy and reliever medications. However, no improvement was seen in PFTs.There is room for improved documentation in terms of symptom recording and use of rescue medicationas as well as for better patient education and counselling in order to improve compliance.

Keywords: asthma, omalizumab, severe allergic asthma, UAE

Procedia PDF Downloads 292

Authors: Cengiz Demir, Recep Keşli, Gülşah Aşık

Abstract:

Objective: This study was carried out with the purpose of defining by using the E test method and determining the antibiotic resistance profiles of Gram-negative anaerobic bacilli isolated from various clinical specimens obtained from patients with suspected anaerobic infections and referred to Medical Microbiology Laboratory of Afyon Kocatepe University, ANS Application and Research Hospital. Methods: Two hundred and seventy eight clinical specimens were examined for isolation of the anaerobic bacteria in Medical Microbiology Laboratory between the 1st November 2014 and 30th October 2015. Specimens were cultivated by using Scheadler agar that 5% defibrinated sheep blood added, and Scheadler broth. The isolated anaerobic Gram-negative bacilli were identified conventional methods and Vitek 2 (ANC ID Card, bioMerieux, France) cards. Antibiotic resistance rates against to penicillin G, clindamycin, cefoxitin, metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem were determined with E-test method for each isolate. Results: Of the isolated twenty-eight anaerobic gram negative bacilli fourteen were identified as the B. fragilis group, 9 were Prevotella group, and 5 were Fusobacterium group. The highest resistance rate was found against penicillin (78.5%) and resistance rates against clindamycin and cefoxitin were found as 17.8% and 21.4%, respectively. Against to the; metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem, no resistance was found. Conclusion: Since high rate resistance has been detected against to penicillin in the study penicillin should not be preferred in empirical treatment. Cefoxitin can be preferred in empirical treatment; however, carrying out the antibiotic sensitivity testing will be more proper and beneficial. No resistance was observed against carbapenem group antibiotics and metronidazole; so that reason, these antibiotics should be reserved for treatment of infectious caused by resistant strains in the future.

Keywords: anaerobic gram-negative bacilli, anaerobe, antibiotics and resistance profiles, e-test method

Procedia PDF Downloads 305

Authors: Wanderson Goncalves e Goncalves, José Alberto Silva de Sá

Abstract:

Human actions are a threat to the balance and conservation of the Amazon forest. Therefore the environmental monitoring services play an important role as the preservation and maintenance of this environment. This study classified forest types using data from a forest inventory provided by the 'Florestal e da Biodiversidade do Estado do Pará' (IDEFLOR-BIO), located between the municipalities of Santarém, Juruti and Aveiro, in the state of Pará, Brazil, covering an area approximately of 600,000 hectares, Bands 3, 4 and 5 of the TM-Landsat satellite image, and Self - Organizing Maps. The information from the satellite images was extracted using QGIS software 2.8.1 Wien and was used as a database for training the neural network. The midpoints of each sample of forest inventory have been linked to images. Later the Digital Numbers of the pixels have been extracted, composing the database that fed the training process and testing of the classifier. The neural network was trained to classify two forest types: Rain Forest of Lowland Emerging Canopy (Dbe) and Rain Forest of Lowland Emerging Canopy plus Open with palm trees (Dbe + Abp) in the Mamuru Arapiuns glebes of Pará State, and the number of examples in the training data set was 400, 200 examples for each class (Dbe and Dbe + Abp), and the size of the test data set was 100, with 50 examples for each class (Dbe and Dbe + Abp). Therefore, total mass of data consisted of 500 examples. The classifier was compiled in Orange Data Mining 2.7 Software and was evaluated in terms of the confusion matrix indicators. The results of the classifier were considered satisfactory, and being obtained values of the global accuracy equal to 89% and Kappa coefficient equal to 78% and F1 score equal to 0,88. It evaluated also the efficiency of the classifier by the ROC plot (receiver operating characteristics), obtaining results close to ideal ratings, showing it to be a very good classifier, and demonstrating the potential of this methodology to provide ecosystem services, particularly in anthropogenic areas in the Amazon.

Keywords: artificial neural network, computational intelligence, pattern recognition, unsupervised learning

Procedia PDF Downloads 361

Authors: Shlomit Hon-Snir, Shosh Shahrabai, Sharon Teitler Regev, Anabel Friedlander-Lifszyc

Abstract:

Today, online travel sites account for a large share of the orders for tourism services, leading to the expectation that many traditional travel agencies will become redundant in the future. Technological changes are offering customers a wider variety and better prices, and the improved competition in the industry has increased customer well-being significantly. Therefore, the question is whether all customers can enjoy this change, specifically whether different groups in the Israeli population enjoy the changes similarly. The purpose of this study is to identify the factors that affect the collection of data and the purchase of tourism products online and in particular to identify the barriers and limitations of technology usage among the population. The results of the current research are of great importance both economically and socially. The theory of Reasoned Action assumes that actual behavior is based on intention. Volitional behavior is predicted by individuals' attitudes to that behavior and by the way they think other people will look at them. Two cognitive variables regarding the use of technology are: perceived usefulness and perceived ease-of-use. Moreover, early adopters of innovations have different characteristics than people that adopt an innovation at a later stage. In the study, we analyze four groups of factors: Customer characteristics, internet usage, technology acceptance and product characteristics. Some of the parameters are gender, age, income level, frequency and type of internet use, proficiency in English, traveler type, number of trips abroad, perceived ease of use, perceived usefulness, perceived risk, perceived trust and product type. We investigate online purchasing and online information search separately. Data will be collected using an online questionnaire distributed among a representative sample of 600 citizens in Israel. Some of the research questions will be based on previous research studies (that underwent reliability and validity testing). Those questions will be translated into Hebrew and adjusted for the tested population.

Keywords: customer characteristics, online travel sites, technology acceptance, tourism

Procedia PDF Downloads 200

Authors: Lidya Hailu, Ramesh Duraisamy, Masood Akhtar Khan, Belete Yilma

Abstract:

Disposable food packaging is a single-use plastics that can include any disposable plastic item which could be designed and use only once. In this context, this study aimed to prepare and evaluate bioplastic food packaging material from avocado seed starch and sugarcane bagasse cellulose and to characterise avocado seed starch. Performed the physicomechanical, structural, thermal properties, and biodegradability of raw materials and readily prepared bioplastic using the universal tensile testing machine, FTIR, UV-Vis spectroscopy, TGA, XRD, and SEM. Results have shown that an increasing amount of glycerol (3-5 mL) resulted in increases in water absorption, density, water vapor permeability, and elongation at the break of prepared bioplastic. However, it causes decreases in % transmittance, thermal degradation, and the tensile strength of prepared bioplastic. Likewise, the addition of cellulose fiber (0-15 %) increases % transmittance ranged (91.34±0.12-63.03±0.05 %), density (0.93±0.04-1.27±0.02 g/cm3), thermal degradation (310.01-321.61°C), tensile strength (2.91±6.18-4.21±6.713 MPa) of prepared bioplastic. On the other hand, it causes decreases in water absorption (14.4±0.25-9.40±0.007 %), water vapor permeability (9.306x10-12±0.3-3.57x10-12±0.15 g•s−1•m−1•Pa−1) and elongation at break (34.46±3.37-27.63±5.67 %) of prepared bioplastic. All the readily prepared bioplastic films rapidly degraded in the soil in the first 6 days and decompose within 12 days with a diminutive leftover and completely degraded within 15 days under an open soil atmosphere. Studied results showed starch derived bioplastic reinforced with 15 % cellulose fiber that plasticized with 3 mL of glycerol had improved results than other combinations of glycerol and bagasse cellulose with avocado seed starch. Thus, biodegradable disposable food packaging cup has been successfully produced in the lab-scale level using the studied approach. Biodegradable disposable food packaging materials have been successfully produced by employing avocado seed starch and sugarcane bagasse cellulose. The future study should be done on nano scale production since this study was done at the micro level.

Keywords: avocado seed, food packaging, glycerol, sugarcane bagasse

Procedia PDF Downloads 338

Authors: Amin Ajabi, Chinchu Cherian, Sumi Siddiqua

Abstract:

Rammed earth (RE) is a traditional soil-based building material made by compressing a mixture of natural earth and binder ingredients such as chalk or lime, in temporary formworks. However, the modern RE uses 5 to 10% cement as a binder in order to meet the strength and durability requirements as per the standard specifications and guidelines. RE construction is considered to be an energy-efficient and environmental-friendly approach when compared to conventional concrete systems, which use 20 to 30% cement. The present study aimed to develop RE mix designs by utilizing non-hazardous wood-based fly ash generated by pulp and paper mills as a partial replacement for cement. The pulp mill fly ash (PPFA)-stabilized RE is considered to be a sustainable approach keeping in view of the massive carbon footprints associated with cement production as well as the adverse environmental impacts due to disposal of PPFA in landfills. For the experimental study, as-received PPFA, as well as PPFA-based geopolymer (synthesized by alkaline activation method), were incorporated as cement substitutes in the RE mixtures. Initially, local soil was collected and characterized by index and engineering properties. The PPFA was procured from a pulp manufacturing mill, and its physicochemical, mineralogical and morphological characterization, as well as environmental impact assessment, was conducted. Further, the various mix designs of RE material incorporating local soil and different proportions of cement, PPFA, and alkaline activator (a mixture of sodium silicate and sodium hydroxide solutions) were developed. The compacted RE specimens were cured and tested for 7-day and 28-day unconfined compressive strength (UCS) variations. Based on UCS results, the optimum mix design was identified corresponding to maximum strength improvement. Further, the cured RE specimens were subjected to freeze-thaw cycle testing for evaluating its performance and durability as a sustainable construction technique under extreme climatic conditions.

Keywords: sustainability, rammed earth, stabilization, pulp mill fly ash, geopolymer, alkaline activation, strength, durability

Procedia PDF Downloads 99

Authors: Catalina Iticescu, Lucian P. Georgescu, Mihaela Timofti, Gabriel Murariu, Catalina Topa

Abstract:

In the field of environmental protection in the EU and also in Romania, strict and clear rules are imposed that are respected. Among those, mandatory municipal wastewater treatment is included. Our study involved Municipal Wastewater Treatment Plant (MWWTP) of Galati. MWWTP began its activity by the end of 2011 and technology is one of the most modern used in the EU. Moreover, to our knowledge, it is the first technology of this kind used in the region. Until commissioning, municipal wastewater was discharged directly into the Danube without any treatment. Besides the benefits of depollution, a new problem has arisen: the accumulation of increasingly large sewage sludge. Therefore, it is extremely important to find economically feasible and environmentally friendly solutions. One of the most feasible methods of disposing of sewage sludge is their use on agricultural land. Sewage sludge can be used in agriculture if monitored in terms of physicochemical properties (pH, nutrients, heavy metals, etc.), in order not to contribute to pollution in soils and not to affect chemical and biological balances, which are relatively fragile. In this paper, 16 physico-chemical parameters were monitored. Experimental testings were realised on waste water samples, sewage sludge results and treated water samples. Testing was conducted with electrochemichal methods (pH, conductivity, TDS); parameters N-total (mg/L), P-total (mg/L), N-NH4 (mg/L), N-NO2 (mg/L), N-NO3 (mg/L), Fe-total (mg/L), Cr-total (mg/L), Cu (mg/L), Zn (mg/L), Cd (mg/L), Pb (mg/L), Ni (mg/L) were determined by spectrophotometric methods using a spectrophotometer NOVA 60 and specific kits. Analyzing the results, we concluded that Sewage sludges, although containing heavy metals, are in small quantities and will not affect the land on which they will be deposited. Also, the amount of nutrients contained are appreciable. These features indicate that the sludge can be safely used in agriculture, with the advantage that they represent a cheap fertilizer. Acknowledgement: This work was supported by a grant of the Romanian National Authority for Scientific Research and Innovation – UEFISCDI, PNCDI III project, 79BG/2017, Efficiency of the technological process for obtaining of sewage sludge usable in agriculture, Efficient.

Keywords: municipal wastewater, physico-chemical properties, sewage sludge, technology

Procedia PDF Downloads 209

Authors: Shilpa Varghese, Adarsh Eregowda

Abstract:

Introduction: The normal development and maturation of the central nervous system is significantly influenced by thyroid hormones. Small for gestational age (SGA) babies have a distinct hormonal profile than kids born at an acceptable birth weight for gestational age, according to several studies (AGA). In SGA babies, thyroid size is larger when expressed as a percentage of body weight, indicating that low thyroid hormone levels throughout foetal life may be partially compensated for. Numerous investigations have found that compared to full-term and preterm AGA neonates, SGA babies exhibit considerably decreased thyroid plasma levels. According to our hypothesis, term and preterm SGA newborns have greater thyroid-stimulating hormone (TSH) concentrations than those that are normal for gestational age (AGA) and a higher incidence of thyroid dysfunction. Need for the study: Clinically diagnosed Assessment of term SGA babies confirming thyroid dysfunction unclear Requirement and importance of ft4 along with tsh and comparative values of ft4 in SGA babies as compared to AGA babies unclear. Inclusion criteria : SGA infants including preterm (<37 weeks of gestation) term (37-40 weeks) – comparing with preterm and term AGA infants. 3.76 7.66 0 2 4 6 8 10 12 AGA Babies SGA Babies Mean Mean TSH Comparison 2.73 1.52 0 0.5 1 1.5 2 2.5 3 3.5 4 AGA Babies SGA Babies Mean Mean FT4 Comparison Discussion : According to this study, neonates with SGA had considerably higher TSH levels than newborns with AGA. Our findings have been supported by results from earlier research. The TSH level range was established to 7.5 mU/L in the study by Bosch-Giménez et al, found greater TSH concentrations in SGA newborns. Thyroid hormone levels from newborns that are tiny for gestational age were found to be higher than AGA in our investigation. According to Franco et al., blood T4 concentrations are lower in both preterm and term SGA infants, while TSH concentrations are only noticeably greater in term SGA infants compared to AGA ones. According to our study analysis, the SGA group had considerably greater FT4 concentrations. Therefore, our findings are consistent with those of the two studies that SGA babies have a higher incidence of transient hypothyroidism and need close follow-up. Conclusions: A greater frequency of thyroid dysfunction and considerably higher TSH values within the normal range were seen in preterm and term SGA babies. The SGA babies who exhibit these characteristics should have ongoing endocrinologic testing and periodic TFTs.

Keywords: thyroid hormone, thyroid function tests, small for gestationl age, appropriate for gestational age

Procedia PDF Downloads 66

Authors: Tigabu Dagne Akal

Abstract:

While advances in computer and communications technology have made the network ubiquitous, they have also rendered networked systems vulnerable to malicious attacks devised from a distance. These attacks or intrusions start with attackers infiltrating a network through a vulnerable host and then launching further attacks on the local network or Intranet. Nowadays, system administrators and network professionals can attempt to prevent such attacks by developing intrusion detection tools and systems using data mining technology. In this study, the experiments were conducted following the Knowledge Discovery in Database Process Model. The Knowledge Discovery in Database Process Model starts from selection of the datasets. The dataset used in this study has been taken from Massachusetts Institute of Technology Lincoln Laboratory. After taking the data, it has been pre-processed. The major pre-processing activities include fill in missed values, remove outliers; resolve inconsistencies, integration of data that contains both labelled and unlabelled datasets, dimensionality reduction, size reduction and data transformation activity like discretization tasks were done for this study. A total of 21,533 intrusion records are used for training the models. For validating the performance of the selected model a separate 3,397 records are used as a testing set. For building a predictive model for intrusion detection J48 decision tree and the Naïve Bayes algorithms have been tested as a classification approach for both with and without feature selection approaches. The model that was created using 10-fold cross validation using the J48 decision tree algorithm with the default parameter values showed the best classification accuracy. The model has a prediction accuracy of 96.11% on the training datasets and 93.2% on the test dataset to classify the new instances as normal, DOS, U2R, R2L and probe classes. The findings of this study have shown that the data mining methods generates interesting rules that are crucial for intrusion detection and prevention in the networking industry. Future research directions are forwarded to come up an applicable system in the area of the study.

Keywords: intrusion detection, data mining, computer science, data mining

Procedia PDF Downloads 296

Authors: Mohamed El Horri, Amine Mouden, Reda Messaoudi, Mohamed Chekkal, Driss Benlaldj, Malika Baghdadi, Lahcene Benmahdi, Fatima Seghier

Abstract:

Background/aim: Recently, the Von Willebrand factor antigen (vWF-Ag)has been identified as a new marker of portal hypertension (PH) and its complications. Few studies talked about its role in the prediction of esophageal varices. VWF-Ag is considered a non-invasive approach, In order to avoid the endoscopic burden, cost, drawbacks, unpleasant and repeated examinations to the patients. In our study, we aimed to evaluate the ability of this marker in the prediction of another complication of portal hypertension, which is portal hypertensive gastropathy (PHG), the one that is diagnosed also by endoscopic tools. Patients and methods: It is about a prospective study, which include 124 cirrhotic patients with no history of bleeding who underwent screening endoscopy for PH-related complications like esophageal varices (EVs) and PHG. Routine biological tests were performed as well as the VWF-Ag testing by both ELFA and Immunoturbidimetric techniques. The diagnostic performance of our marker was assessed using sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and receiver operating characteristic curves. Results: 124 patients were enrolled in this study, with a mean age of 58 years [CI: 55 – 60 years] and a sex ratio of 1.17. Viral etiologies were found in 50% of patients. Screening endoscopy revealed the presence of PHG in 20.2% of cases, while for EVsthey were found in 83.1% of cases. VWF-Ag levels, were significantly increased in patients with PHG compared to those who have not: 441% [CI: 375 – 506], versus 279% [CI: 253 – 304], respectively (p <0.0001). Using the area under the receiver operating characteristic curve (AUC), vWF-Ag was a good predictor for the presence of PHG. With a value higher than 320% and an AUC of 0.824, VWF-Ag had an 84% sensitivity, 74% specificity, 44.7% positive predictive value, 94.8% negative predictive value, and 75.8% diagnostic accuracy. Conclusion: VWF-Ag is a good non-invasive low coast marker for excluding the presence of PHG in patients with liver cirrhosis. Using this marker as part of a selective screening strategy might reduce the need for endoscopic screening and the coast of the management of these kinds of patients.

Keywords: von willebrand factor, portal hypertensive gastropathy, prediction, liver cirrhosis

Procedia PDF Downloads 205

Authors: Antonio M. Oliveira, Patricia Oliveira-Silva, Jose Matias Alves, Gary McPherson

Abstract:

The music teaching is oriented towards offering formal music training. Due to its specificities, this vocational program starts at a very young age. Although provided by the State, the offer is limited to 6 schools throughout the country, which means that the vacancies for prospective students are very limited every year. It is therefore crucial that these vacancies be taken by especially motivated children grown within households that offer the ideal setting for success. Some of the instruments used to evaluate musical performance are highly sensitive to specific previous training, what represents a severe validity problem for testing children who have had restricted opportunities for formal training. Moreover, these practices may be unfair because, for instance, they may not reflect the candidates’ music aptitudes. Based on what constitutes a prerequisite for making an excellent music student, researchers in this field have long argued that motivation, task commitment, and parents’ support are as important as ability. Thus, the aim of this study is: (1) to prepare an inventory of admission requirements in Australia, Portugal and Ireland; (2) to examine whether the candidates to music conservatories and parents’ level of motivation, assessed at three evaluation points (i.e., admission, at the end of the first year, and at the end of the second year), correlates positively with the candidates’ progress in learning a musical instrument (i.e., whether motivation at the admission may predict student musicianship); (3) an adaptation of an existing instrument to assess the motivation (i.e., to adapt the items to the music setting, focusing on the motivation for playing a musical instrument). The inclusion criteria are: only children registered in the administrative services to be evaluated for entrance to the conservatory will be accepted for this study. The expected number of participants is fifty (5-6 years old) in all the three frequency schemes: integrated, articulated and supplementary. Revisiting musical admission procedures is of particular importance and relevance to musical education because this debate may bring guidance and assistance about the needed improvement to make the process of admission fairer and more transparent.

Keywords: music learning, music admission requirements, student’s motivation, parent’s motivation

Procedia PDF Downloads 166

Authors: Thien Van Ngo

Abstract:

The engineering design process is a systematic approach to solving problems. It involves identifying a problem, brainstorming solutions, prototyping and testing solutions, and evaluating the results. The engineering design process can be used to teach students how to solve problems in a creative and innovative way. The research aim of this study was to investigate the effectiveness of using the engineering design process to enhance student learning outcomes in a physics course. A mixed research method was used in this study. The quantitative data were collected using a pretest-posttest control group design. The qualitative data were collected using semi-structured interviews. The sample was 150 first-year students in the Department of Mechanical Engineering Technology at Cao Thang Technical College in Vietnam in the 2022-2023 school year. The quantitative data were collected using a pretest-posttest control group design. The pretest was administered to both groups at the beginning of the study. The posttest was administered to both groups at the end of the study. The qualitative data were collected using semi-structured interviews with a sample of eight students in the experimental group. The interviews were conducted after the posttest. The quantitative data were analyzed using independent sample T-tests. The qualitative data were analyzed using thematic analysis. The quantitative data showed that students in the experimental group, who were taught using the engineering design process, had significantly higher post-test scores on physics problem-solving than students in the control group, who were taught using the conventional method. The qualitative data showed that students in the experimental group were more motivated and engaged in the learning process than students in the control group. Students in the experimental group also reported that they found the engineering design process to be a more effective way of learning physics. The findings of this study suggest that the engineering design process can be an effective way of enhancing student learning outcomes in physics courses. The engineering design process engages students in the learning process and helps them to develop problem-solving skills.

Keywords: engineering design process, problem-solving, learning outcome of physics, students’ physics competencies, deep learning

Procedia PDF Downloads 65