Search results for: accident investigation and analysis
11612 Analytical Modeling of Drain Current for DNA Biomolecule Detection in Double-Gate Tunnel Field-Effect Transistor Biosensor
Authors: Ashwani Kumar
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Abstract- This study presents an analytical modeling approach for analyzing the drain current behavior in Tunnel Field-Effect Transistor (TFET) biosensors used for the detection of DNA biomolecules. The proposed model focuses on elucidating the relationship between the drain current and the presence of DNA biomolecules, taking into account the impact of various device parameters and biomolecule characteristics. Through comprehensive analysis, the model offers insights into the underlying mechanisms governing the sensing performance of TFET biosensors, aiding in the optimization of device design and operation. A non-local tunneling model is incorporated with other essential models to accurately trace the simulation and modeled data. An experimental validation of the model is provided, demonstrating its efficacy in accurately predicting the drain current response to DNA biomolecule detection. The sensitivity attained from the analytical model is compared and contrasted with the ongoing research work in this area.Keywords: biosensor, double-gate TFET, DNA detection, drain current modeling, sensitivity
Procedia PDF Downloads 5711611 A Comparative Analysis of Residential Quality of Public and Private Estates in Lagos
Authors: S. Akinde, Jubril Olatunbosun
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In recent years, most of the urban centers in Nigeria are fast experiencing housing problems such as unaffordable housing and environmental challenges, all of which determine the nature of housing quality. The population continues to increase and the demand for quality housing increases probably at the same rate. Several kinds of houses serve various purposes; the objectives of the low cost housing schemes as the name suggests is to make houses quality to both the middle and lower classes of people in Lagos. A casual look into the study area of Iba Low Cost Housing Estate and the Unity Low Cost Housing Estate, Ojo and Alimosho respectively in Lagos State have shown a huge demands for houses. The study area boasts of a large population all engaged in various commercial activities with income at various levels. It would be fair to say that these people are mainly of the middle class and lower class. This means the low cost housing scheme truly serves these purposes. A Low Cost Housing Scheme of Iba which is publicly owned and Low Cost Housing Scheme of Unity Estate (UE) is privately owned.Keywords: housing, residential quality, low cost housing scheme, public, private estates
Procedia PDF Downloads 56311610 Heat Transfer Phenomena Identification of a Non-Active Floor in a Stack-Ventilated Building in Summertime: Empirical Study
Authors: Miguel Chen Austin, Denis Bruneau, Alain Sempey, Laurent Mora, Alain Sommier
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An experimental study in a Plus Energy House (PEH) prototype was conducted in August 2016. It aimed to highlight the energy charge and discharge of a concrete-slab floor submitted to the day-night-cycles heat exchanges in the southwestern part of France and to identify the heat transfer phenomena that take place in both processes: charge and discharge. The main features of this PEH, significant to this study, are the following: (i) a non-active slab covering the major part of the entire floor surface of the house, which include a concrete layer 68 mm thick as upper layer; (ii) solar window shades located on the north and south facades along with a large eave facing south, (iii) large double-glazed windows covering the majority of the south facade, (iv) a natural ventilation system (NVS) composed by ten automatized openings with different dimensions: four are located on the south facade, four on the north facade and two on the shed roof (north-oriented). To highlight the energy charge and discharge processes of the non-active slab, heat flux and temperature measurement techniques were implemented, along with airspeed measurements. Ten “measurement-poles” (MP) were distributed all over the concrete-floor surface. Each MP represented a zone of measurement, where air and surface temperatures, and convection and radiation heat fluxes, were intended to be measured. The airspeed was measured only at two points over the slab surface, near the south facade. To identify the heat transfer phenomena that take part in the charge and discharge process, some relevant dimensionless parameters were used, along with statistical analysis; heat transfer phenomena were identified based on this analysis. Experimental data, after processing, had shown that two periods could be identified at a glance: charge (heat gain, positive values) and discharge (heat losses, negative values). During the charge period, on the floor surface, radiation heat exchanges were significantly higher compared with convection. On the other hand, convection heat exchanges were significantly higher than radiation, in the discharge period. Spatially, both, convection and radiation heat exchanges are higher near the natural ventilation openings and smaller far from them, as expected. Experimental correlations have been determined using a linear regression model, showing the relation between the Nusselt number with relevant parameters: Peclet, Rayleigh, and Richardson numbers. This has led to the determination of the convective heat transfer coefficient and its comparison with the convective heat coefficient resulting from measurements. Results have shown that forced and natural convection coexists during the discharge period; more accurate correlations with the Peclet number than with the Rayleigh number, have been found. This may suggest that forced convection is stronger than natural convection. Yet, airspeed levels encountered suggest that it is natural convection that should take place rather than forced convection. Despite this, Richardson number values encountered indicate otherwise. During the charge period, air-velocity levels might indicate that none air motion occurs, which might lead to heat transfer by diffusion instead of convection.Keywords: heat flux measurement, natural ventilation, non-active concrete slab, plus energy house
Procedia PDF Downloads 41611609 Wasteless Solid-Phase Method for Conversion of Iron Ores Contaminated with Silicon and Phosphorus Compounds
Authors: А. V. Panko, Е. V. Ablets, I. G. Kovzun, М. А. Ilyashov
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Based upon generalized analysis of modern know-how in the sphere of processing, concentration and purification of iron-ore raw materials (IORM), in particular, the most widespread ferrioxide-silicate materials (FOSM), containing impurities of phosphorus and other elements compounds, noted special role of nano technological initiatives in improvement of such processes. Considered ideas of role of nano particles in processes of FOSM carbonization with subsequent direct reduction of ferric oxides contained in them to metal phase, as well as in processes of alkali treatment and separation of powered iron from phosphorus compounds. Using the obtained results the wasteless solid-phase processing, concentration and purification of IORM and FOSM from compounds of phosphorus, silicon and other impurities excelling known methods of direct iron reduction from iron ores and metallurgical slimes.Keywords: iron ores, solid-phase reduction, nanoparticles in reduction and purification of iron from silicon and phosphorus, wasteless method of ores processing
Procedia PDF Downloads 48811608 Analysis of Influence of Intrinsic Motivation on Employee Affective Commitment
Authors: Yashar Ibragimov, Nino Berishvili
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Technological, economic and other innovation-related advances of the 21st century have influenced the old, traditional business models. Presently, organizational change has become an integral part of corporate strategy for the majority of businesses. Such shifts have resulted in both new challenges and opportunities. The expansion of the use of information and communication technologies has driven fundamental shifts towards digital change. Organizations are being forced to revise processes, goals and overall mission in order to stay competitive in the marketplace. However, the implementation of digital transformation brings uncertainty, causes stress and raises concerns about future jobs. The study employs systematic literature review to fill the gap in understanding relationship between employee motivation and commitment during the transformation. A conceptual model proposes the antecedents (OCB and Leader Member Exchange) of employee motivation and investigates its impact on employee commitment to change. The utilized model elucidates how to maintain employee motivation and commitment in the context of organizational transformation and sets the ground for future research.Keywords: employee motivation, change commitment, change management, leader member exchange, organizational citizenship behavior
Procedia PDF Downloads 7811607 Comparison of Mean Monthly Soil Temperature at (5 and 30 cm) Depths at Compton Experimental Site, West Midlands (UK), between 1976-2008
Authors: Aminu Mansur
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A comparison of soil temperature at (5 and 30 cm) depths at a research site over the period (1976-2008) was analyzed. Based on the statistical analysis of the database of (12,045) days of individual soil temperature measurements in sandy-loam of the (salwick series) soils, the mean soil temperature revealed a statistically significant increase of about -1.1 to 10.9°C at 5 cm depth in 1976 compared to 2008. Similarly, soil temperature at 30 cm depth increased by -0.1 to 2.1°C in 2008 compared to 1976. Although, rapid increase in soil temperature at all depths was observed during that period, but a thorough assessment of these conditions suggested that the soil temperature at 5 cm depth are progressively increasing over time. A typical example of those increases in soil temperature was provided for agriculture where Miscanthus (elephant) plant that grows within the study area is adversely affected by the mean soil temperature increase. The study concluded that these observations contribute to the growing mass of evidence of global warming and knowledge on secular trends. Therefore, there was statistically significant increase in soil temperature at Compton Experimental Site between 1976-2008.Keywords: soil temperature, warming trend, environment science, climate and atmospheric sciences
Procedia PDF Downloads 29811606 Effectiveness of Crystallization Coating Materials on Chloride Ions Ingress in Concrete
Authors: Mona Elsalamawy, Ashraf Ragab Mohamed, Abdellatif Elsayed Abosen
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This paper aims to evaluate the effectiveness of different crystalline coating materials concerning of chloride ions penetration. The concrete ages at the coating installation and its moisture conditions were addressed; where, these two factors may play a dominant role for the effectiveness of the used materials. Rapid chloride ions penetration test (RCPT) was conducted at different ages and moisture conditions according to the relevant standard. In addition, the contaminated area and the penetration depth of the chloride ions were investigated immediately after the RCPT test using chemical identifier, 0.1 M silver nitrate AgNO3 solution. Results have shown that, the very low chloride ions penetrability, for the studied crystallization materials, were investigated only with the old age concrete (G1). The significant reduction in chloride ions’ penetrability was illustrated after 7 days of installing the crystalline coating layers. Using imageJ is more reliable to describe the contaminated area of chloride ions, where the distribution of aggregate and heterogeneous of cement mortar was considered in the images analysis.Keywords: chloride permeability, contaminated area, crystalline waterproofing materials, RCPT, XRD
Procedia PDF Downloads 25111605 Exploring the Impact of Additive Manufacturing on Supply Chains: A Game-Theoretic Analysis of Manufacturer-Retailer Dynamics
Authors: Mohammad Ebrahim Arbabian
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This paper investigates the impact of 3D printing, also known as additive manufacturing, on a multi-item supply chain comprising a manufacturer and retailer. Operating under a wholesale-price contract and catering to stochastic customer demand, this study delves into the largely unexplored realm of how 3D printing technology reshapes supply chain dynamics. A distinguishing aspect of 3D printing is its versatility in producing various product types, yet its slower production pace compared to traditional methods poses a challenge. We analyze the trade-off between 3D printing's limited capacity and its enhancement of production flexibility. By delineating the economic circumstances favoring 3D printing adoption by the manufacturer, we establish the Stackelberg equilibrium in the retailer-manufacturer game. Additionally, we determine optimal order quantities for the retailer considering 3D printing as an option for the manufacturer, ascertain optimal wholesale prices in the presence of 3D printing, and compute optimal profits for both parties involved in the supply chain.Keywords: additive manufacturing, supply chain management, contract theory, Stackelberg game, optimization
Procedia PDF Downloads 6111604 Experiences and Perceptions of Parents Raising Children with Autism
Authors: Tamene Keneni, Tibebu Yohannes
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The prevalence of autism spectrum disorder (ASD) in general and autism in particular is on the rise globally, and the need for evidence-based intervention and care for children with autism has grown, too. However, evidence on autism is scanty in developing countries, including Ethiopia. With the aim to help fill the gap and paucity in research into the issue, the main purpose of this study is to explore, better understand, and document the experiences and perceptions of parents of children with autism. To this end, we used a qualitative survey to collect data from a convenient sample of parents raising a child with autism. The data collected were subjected to qualitative analysis that yielded several themes and subthemes, including late diagnosis, parents’ reactions to diagnosis, sources of information during and after diagnosis, differing reactions to having a child with autism from siblings, extended family members, and the larger community, attribution of autism to several causes by the community, lack of recognition and open discussion of autism and lack of appropriated public educational and health care services for children with autism and their parents. The themes and subthemes identified were discussed in light of existing literature, and implications for practice were drawn.Keywords: ASD, autism, children with autism, raising children with autism
Procedia PDF Downloads 16911603 Validating the Theme Park Service Quality Scale: A Case Study of Zhuhai Chimelong Ocean Kingdom
Authors: Kat Jingjing Luo
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The development of theme parks in China has been through a rapid growth in the past decades. Increasing competition within service quality has forced theme park managers concerned the relationship between service quality and visitors’ satisfaction. Even though those existing service quality measurements such as SERVQUAL and THEMEQUAL have been applied in related researches, none of them is exclusive for Chinese theme park service quality. This study aims to investigate the service quality of the most popular theme park in China currently and develop a unique, reliable and valid scale. The reliability and validity analysis results from a survey of over 200 tourists in Chimelong ocean kingdom in Zhuhai city, south of China, indicate that the dimension of waiting time is a discover factor in the measurement of Chinese theme park service quality excluding in the THEMEQUAL instrument (i.e., tangibles, reliability, responsiveness and access, assurance, empathy and courtesy). The newly developed scale gives a better understand service quality in Chinese theme park industry, and the managerial implications in regard to the research, how to improve theme park service quality are discussed.Keywords: theme park, scale development, China, service quality
Procedia PDF Downloads 27911602 Critical Analysis of Ideology of Non-Religious Spirituality (SBNR) Case Study of Sam Harris’ Theory
Authors: Muhammad Samiullah
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Religion and spirit always goes side by side. In this era spirit and religion are studied separately with thought of an anti-religious phenomenon is there with its vast impacts. Non-religious mind and religious one have a lot of things that differs, they have spiritual struggles.so there is theme arises that is in the name of non-religious spirituality(SBNR). The thinking prevailing in west and now in east in reverse of the religious institutional thought and spirituality. Religious disputes created an image to the world that is nontolerant and companionate, rising a question of god existence and self-existence. Thus giving rise in Atheism, nihilism, free thinking. The thinking of spirituality also gone in another side with superstitions and spiritual meditation. Christian religious bodies and scholar criticized the stance with their religious aspect but there should be an Islamic counter narrative should be there. Here in this dissertation the phenomenon is addressed and analyzed in respect with some of the literature presented from 2014 till present year. The phenomenon was not analyzed before in broader sense. There are some introductory and static views presented in this regard. So there is a literature gap to be filled by this effort, the Muslim counter narrative is still not there though Christians do their part.Keywords: SBNR, non-spirituality, superstitions, Sam Harris
Procedia PDF Downloads 9111601 Stripping of Flavour-Active Compounds from Aqueous Food Streams: Effect of Liquid Matrix on Vapour-Liquid Equilibrium in a Beer-Like Solution
Authors: Ali Ammari, Karin Schroen
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In brewing industries, stripping is a downstream process to separate volatiles from beer. Due to physiochemical similarities between flavour components, the selectivity of this method is not favourable. Besides, the presence of non-volatile compounds such as proteins and carbohydrates may affect the separation of flavours due to their retaining properties. By using a stripping column with structured packing coupled with a gas chromatography, in this work, the overall mass transfer coefficient along with their corresponding equilibrium data was investigated for a model solution consist of water, ethanol, ethyl acetate and isoamyl acetate. Static headspace analysis also was employed to derive equilibrium data for flavours in the presence of beer dry matter. As it was expected ethanol and dry matter showed retention properties; however, the effect of viscosity in mass transfer coefficient was discarded due to the fact that the viscosity of solution decreased during stripping. The effect of ethanol and beer dry matter were mapped to be used for designing stripping could.Keywords: flavour, headspace, Henry’s coefficient, mass transfer coefficient, stripping
Procedia PDF Downloads 19411600 The Determination of the Potassium Nitrate, Sodium Hydroxide and Boric Acid Molar Ratio in the Synthesis of Potassium Borates via Hydrothermal Method
Authors: M. Yildirim, A. S. Kipcak, F. T. Senberber, M. O. Asensio, E. M. Derun, S. Piskin
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Potassium borates, which are widely used in welding and metal refining industry, as a lubricating oil additive, cement additive, fiberglass additive and insulation compound, are one of the important groups of borate minerals. In this study the production of a potassium borate mineral via hydrothermal method is aimed. The potassium source of potassium nitrate (KNO3) was used along with a sodium source of sodium hydroxide (NaOH) and boron source of boric acid (H3BO3). The constant parameters of reaction temperature and reaction time were determined as 80°C and 1 h, respectively. The molar ratios of 1:1:3 (as KNO3:NaOH:H3BO3), 1:1:4, 1:1:5, 1:1:6 and 1:1:7 were used. Following the synthesis the identifications of the produced products were conducted by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). The results of the experiments and analysis showed in the ratio of 1:1:6, the Santite mineral with powder diffraction file number (pdf no.) of 01-072-1688, which is known as potassium pentaborate (KB5O8•4H2O) was synthesized as best.Keywords: hydrothermal synthesis, potassium borate, potassium nitrate, santite
Procedia PDF Downloads 46011599 Availability and the Utilization of Recreational Facilities for Prison Inmate Rehabilitation
Authors: Thomas Ejobowah Boye, Philip Oghenetega Ekpon
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The paper examines the availability and the utilization of recreational facilities for prison inmate’s rehabilitation in Nigeria. In order to carry out the study the researchers visited sampled prisons in the six geo-political zones in Nigeria. Instant assessment of available recreational facilities was carried out. Inmates were asked to tick a self-design questionnaire that was validated by experts in the Departments of Physical and Health Education, Delta State University and the College of Physical Education, Mosogar on available recreational facilities and activities engaged in by them. The data collected was subjected to percentage analysis. The study revealed that there is little or no standard recreational facilities in all the prisons visited. Considering the role physical activities play in the overall development of individuals physically, mentally, emotionally, morally, and socially it was recommended that the authorities of the Nigerian prisons should as a matter of urgency include recreational activities as a means of reforming and rehabilitating prison inmates. To achieve the desire to rehabilitate prison inmates the researchers also recommended that facilities and equipment should be made available in all prisons in Nigeria.Keywords: facility, prison, recreation, rehabilitation
Procedia PDF Downloads 59511598 Analysis of Causality between Economic Growth and Carbon Emissions: The Case of Mexico 1971-2011
Authors: Mario Gómez, José Carlos Rodríguez
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This paper analyzes the Environmental Kuznets Curve (EKC) hypothesis to test the causality relationship between economic activity, trade openness and carbon dioxide emissions in Mexico (1971-2011). The results achieved in this research show that there are three long-run relationships between production, trade openness, energy consumption and carbon dioxide emissions. The EKC hypothesis was not verified in this research. Indeed, it was found evidence of a short-term unidirectional causality from GDP and GDP squared to carbon dioxide emissions, from GDP, GDP squared and TO to EC, and bidirectional causality between TO and GDP. Finally, it was found evidence of long-term unidirectional causality from all variables to carbon emissions. These results suggest that a reduction in energy consumption, economic activity, or an increase in trade openness would reduce pollution.Keywords: causality, cointegration, energy consumption, economic growth, environmental Kuznets curve
Procedia PDF Downloads 35111597 Performance of Axially Loaded Single Pile Embedded in Cohesive Soil with Cavities
Authors: Ali A. Al-Jazaairry, Tahsin T. Sabbagh
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The stability of a single model pile located adjacent to a continuous cavity was studied. This paper is an attempt to understand the behaviour of axially loaded single pile embedded in clayey soil with the presences of cavities. The performance of piles located in such soils was studied analytically. A verification analysis was carried out on available studies to assess the ability of analytical model to correctly interpret the system behaviour. The study was adopted by finite element program (PLAXIS). The study included many cases; in each case, there is a critical value in which the presence of cavities has shown minimum effect on the pile performance. Figures including the load carrying capacity of pile with the affecting factors are presented. These figures provide beneficial information for pile design constructed close to underground cavities. It was concluded that the load carrying capacity of the pile is reduced by the presence of the cavity within the soil mass. This reduction varies according to the size and location of cavity.Keywords: axial load, cavity, clay, pile, ultimate capacity
Procedia PDF Downloads 27111596 Evaluating Forecasts Through Stochastic Loss Order
Authors: Wilmer Osvaldo Martinez, Manuel Dario Hernandez, Juan Manuel Julio
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We propose to assess the performance of k forecast procedures by exploring the distributions of forecast errors and error losses. We argue that non systematic forecast errors minimize when their distributions are symmetric and unimodal, and that forecast accuracy should be assessed through stochastic loss order rather than expected loss order, which is the way it is customarily performed in previous work. Moreover, since forecast performance evaluation can be understood as a one way analysis of variance, we propose to explore loss distributions under two circumstances; when a strict (but unknown) joint stochastic order exists among the losses of all forecast alternatives, and when such order happens among subsets of alternative procedures. In spite of the fact that loss stochastic order is stronger than loss moment order, our proposals are at least as powerful as competing tests, and are robust to the correlation, autocorrelation and heteroskedasticity settings they consider. In addition, since our proposals do not require samples of the same size, their scope is also wider, and provided that they test the whole loss distribution instead of just loss moments, they can also be used to study forecast distributions as well. We illustrate the usefulness of our proposals by evaluating a set of real world forecasts.Keywords: forecast evaluation, stochastic order, multiple comparison, non parametric test
Procedia PDF Downloads 8911595 Modified Surface Morphology, Structure and Enhanced Weathering Performance of Polyester-Urethane/Organoclay Nanocomposite Coatings
Authors: Gaurav Verma
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Organoclay loaded (0-5 weight %) polyester-urethane (PU) coatings were prepared with a branched hydroxyl-bearing polyester and an aliphatic poly-isocyanate. TEM micrographs show partial exfoliation and intercalation of clay platelets in organoclay-polyester dispersions. AFM surface images reveals that the PU hard domains tend to regularise and also self-organise into spherical shapes of sizes 50 nm (0 wt %), 60 nm (2 wt %) and 190 nm (4 wt %) respectively. IR analysis shows that PU chains have increasing tendency to interact with exfoliated clay platelets through hydrogen bonding. This interaction strengthens inter-chain linkages in PU matrix and hence improves anti-ageing properties. 1000 hours of accelerated weathering was evaluated by ATR spectroscopy, while yellowing and overall discoloration was quantified by the Δb* and ΔE* values of the CIELab colour scale. Post-weathering surface properties also showed improvement as the loss of thickness and reduction in gloss in neat PU was 25% and 42%; while it was just 3.5% and 14% respectively for the 2 wt% nanocomposite coating. This work highlights the importance of modifying surface and bulk properties of PU coatings at nanoscale, which led to improved performance in accelerated weathering conditions.Keywords: coatings, AFM, ageing, spectroscopy
Procedia PDF Downloads 45411594 Vibration Analysis of Power Lines with Moving Dampers
Authors: Mohammad Bukhari, Oumar Barry
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In order to reduce the Aeolian vibration of overhead transmission lines, the Stockbridge damper is usually attached. The efficiency of Stockbridge damper depends on its location on the conductor and its resonant frequencies. When the Stockbridge damper is located on a vibration node, it becomes inefficient. Hence, the static damper should be subrogated by a dynamic one. In the present study, a proposed dynamic absorber for transmission lines is studied. Hamilton’s principle is used to derive the governing equations, then the system of ordinary differential equations is solved numerically. Parametric studies are conducted to determine how certain parameters affect the performance of the absorber. The results demonstrate that replacing the static absorber by a dynamic one enhance the absorber performance for wider range of frequencies. The results also indicate that the maximum displacement decreases as the absorber speed and the forcing frequency increase. However, this reduction in maximum displacement is accompanying with increasing in the steady state vibration displacement. It is also indicated that the energy dissipation in moving absorber covers higher range of frequencies.Keywords: absorber performance, Aeolian vibration, Hamilton’s principle, stockbridge damper
Procedia PDF Downloads 26711593 Internalizing and Externalizing Problems as Predictors of Student Wellbeing
Authors: Nai-Jiin Yang, Tyler Renshaw
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Prior research has suggested that youth internalizing and externalizing problems significantly correlate with student subjective wellbeing (SSW) and achievement problems (SAP). Yet, only a few studies have used data from mental health screener based on the dual-factor model to explore the empirical relationships among internalizing problems, externalizing problems, academic problems, and student wellbeing. This study was conducted through a secondary analysis of previously collected data in school-wide mental health screening activities across secondary schools within a suburban school district in the western United States. The data set included 1880 student responses from a total of two schools. Findings suggest that both internalizing and externalizing problems are substantial predictors of both student wellbeing and academic problems. However, compared to internalizing problems, externalizing problems were a much stronger predictor of academic problems. Moreover, this study did not support academic problems that moderate the relationship between SSW and youth internalizing problems (YIP) and between youth externalizing problems (YEP) and SSW. Lastly, SAP is the strongest predictor of SSW than YIP and YEP.Keywords: academic problems, externalizing problems, internalizing problems, school mental health, student wellbeing, universal mental health screening
Procedia PDF Downloads 8411592 Pluripotent Stem Cells as Therapeutic Tools for Limbal Stem Cell Deficiencies and Drug Testing
Authors: Aberdam Edith, Sangari Linda, Petit Isabelle, Aberdam Daniel
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Background and Rationale: Transparent avascularised cornea is essential for normal vision and depends on limbal stem cells (LSC) that reside between the cornea and the conjunctiva. Ocular burns or injuries may destroy the limbus, causing limbal stem cell deficiency (LSCD). The cornea becomes vascularised by invaded conjunctival cells, the stroma is scarring, resulting in corneal opacity and loss of vision. Grafted autologous limbus or cultivated autologous LCS can restore the vision, unless the two eyes are affected. Alternative cellular sources have been tested in the last decades, including oral mucosa or hair follicle epithelial cells. However, only partial success has been achieved by the use of these cells since they were not able to uniformly commit into corneal epithelial cells. Human pluripotent stem cells (iPSC) display both unlimited growth capacity and ability to differentiate into any cell type. Our goal was to design a standardized and reproducible protocol to produce transplantable autologous LSC from patients through cell reprogramming technology. Methodology: First, keratinocyte primary culture was established from a small number of plucked hair follicles of healthy donors. The resulting epithelial cells were reprogrammed into induced pluripotent stem cells (iPSCs) and further differentiate into corneal epithelial cells (CEC), according to a robust protocol that recapitulates the main step of corneal embryonic development. qRT-PCR analysis and immunofluorescent staining during the course of differentiation confirm the expression of stage specific markers of corneal embryonic lineage. First appear ectodermal progenitor-specific cytokeratins K8/K18, followed at day 7 by limbal-specific PAX6, TP63 and cytokeratins K5/K14. At day 15, K3/K12+-corneal cells are present. To amplify the iPSC-derived LSC (named COiPSC), intact small epithelial colonies were detached and cultivated in limbal cell-specific medium. In that culture conditions, the COiPSC can be frozen and thaw at any passage, while retaining their corneal characteristics for at least eight passages. To evaluate the potential of COiPSC as an alternative ocular toxicity model, COiPSC were treated at passage P0 to P4 with increasing amounts of SDS and Benzalkonium. Cell proliferation and apoptosis of treated cells was compared to LSC and the SV40-immortalized human corneal epithelial cell line (HCE) routinely used by cosmetological industrials. Of note, HCE are more resistant to toxicity than LSC. At P0, COiPSC were systematically more resistant to chemical toxicity than LSC and even to HCE. Remarkably, this behavior changed with passage since COiPSC at P2 became identical to LSC and thus closer to physiology than HCE. Comparative transcriptome analysis confirmed that COiPSC from P2 are similar to a mixture of LSC and CEC. Finally, by organotypic reconstitution assay, we demonstrated the ability of COiPSC to produce a 3D corneal epithelium on a stromal equivalent made of keratocytes. Conclusion: COiPSC could become valuable for two main applications: (1) an alternative robust tool to perform, in a reproducible and physiological manner, toxicity assays for cosmetic products and pharmacological tests of drugs. (2). COiPSC could become an alternative autologous source for cornea transplantation for LSCD.Keywords: Limbal stem cell deficiency, iPSC, cornea, limbal stem cells
Procedia PDF Downloads 41411591 Analysis of Total Acid in Arabica Coffee Beans after Fermentation with Ohmic Technology
Authors: Reta
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Coffee is widely consumed not only because of its typical taste, but coffee has antioxidant properties because of its polyphenols, and it stimulates brain's performance. The main problem with the consumption of coffee is its content of caffeine. Caffeine, when consumed in excess, can increase muscle tension, stimulate the heart, and increase the secretion of gastric acid. In this research, we applied ohmic-based fermentation technology, which is specially designed to mimic the stomach. We used Arabica coffee, which although cheaper than Luwak coffee, has high acidity, which needs to be reduced. Hence, we applied the ohmic technology, varied the time and temperature of the process and measured the total acidity of the coffee to determine optimum fermentation conditions. Results revealed total acidity of the coffee varied with fermentation conditions; 0.32% at 400C and 12 hr, and 0.52% at 400C and 6 hr. The longer the fermentation, the lower was the acidity. The acidity of the mongoose-fermented (natural fermentation) beans was 2.34%, which is substantially higher than the acidity of the ohmic samples. Ohmic-based fermentation technology, therefore, offers improvements in coffee quality, and this is discussed to highlight the potential of ohmic technology in coffee processing.Keywords: ohmic technology, fermentation, coffee quality, Arabica coffee
Procedia PDF Downloads 34211590 New Possibilities for Testing UX and UI Design on Mobile Devices
Authors: Jakub Berčík, Anna Mravcová, Jana Gálová, Katarína Neomániová
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In an era when everything is increasingly digital, consumers are always looking for new options in solutions to their everyday needs. In this context, mobile apps are developing at an exponential pace. One of the fastest growing segments of mobile technologies is, obviously, e-commerce. It can be predicted that mobile commerce will record nearly three times the global growth of e-commerce across all platforms, which indicates its importance in the given segment. The current coronavirus pandemic is also changing many of the existing paradigms both socially, economically, and technologically, which has a major impact on changing consumer behaviour and the emphasis on simplification and clarity of mobile solutions. This is the area that user experience (UX) and user interface (UI) designers deal with. Their task is to design a sufficiently attractive and interesting solution that will be available on all mobile devices and at the same time will be easy enough for the customer/visitor to get to the destination or to get the necessary information in a few clicks. The basis for changes in UX design can now be obtained not only through online analytical tools but also through neuromarketing, especially in the case of mobile devices. The paper highlights new possibilities for testing UX design applications on mobile devices using a special platform that combines a stationary eye camera (eye tracking) and facial analysis (facial coding).Keywords: emotions, mobile design, user experience, visual attention
Procedia PDF Downloads 12711589 Comparing Test Equating by Item Response Theory and Raw Score Methods with Small Sample Sizes on a Study of the ARTé: Mecenas Learning Game
Authors: Steven W. Carruthers
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The purpose of the present research is to equate two test forms as part of a study to evaluate the educational effectiveness of the ARTé: Mecenas art history learning game. The researcher applied Item Response Theory (IRT) procedures to calculate item, test, and mean-sigma equating parameters. With the sample size n=134, test parameters indicated “good” model fit but low Test Information Functions and more acute than expected equating parameters. Therefore, the researcher applied equipercentile equating and linear equating to raw scores and compared the equated form parameters and effect sizes from each method. Item scaling in IRT enables the researcher to select a subset of well-discriminating items. The mean-sigma step produces a mean-slope adjustment from the anchor items, which was used to scale the score on the new form (Form R) to the reference form (Form Q) scale. In equipercentile equating, scores are adjusted to align the proportion of scores in each quintile segment. Linear equating produces a mean-slope adjustment, which was applied to all core items on the new form. The study followed a quasi-experimental design with purposeful sampling of students enrolled in a college level art history course (n=134) and counterbalancing design to distribute both forms on the pre- and posttests. The Experimental Group (n=82) was asked to play ARTé: Mecenas online and complete Level 4 of the game within a two-week period; 37 participants completed Level 4. Over the same period, the Control Group (n=52) did not play the game. The researcher examined between group differences from post-test scores on test Form Q and Form R by full-factorial Two-Way ANOVA. The raw score analysis indicated a 1.29% direct effect of form, which was statistically non-significant but may be practically significant. The researcher repeated the between group differences analysis with all three equating methods. For the IRT mean-sigma adjusted scores, form had a direct effect of 8.39%. Mean-sigma equating with a small sample may have resulted in inaccurate equating parameters. Equipercentile equating aligned test means and standard deviations, but resultant skewness and kurtosis worsened compared to raw score parameters. Form had a 3.18% direct effect. Linear equating produced the lowest Form effect, approaching 0%. Using linearly equated scores, the researcher conducted an ANCOVA to examine the effect size in terms of prior knowledge. The between group effect size for the Control Group versus Experimental Group participants who completed the game was 14.39% with a 4.77% effect size attributed to pre-test score. Playing and completing the game increased art history knowledge, and individuals with low prior knowledge tended to gain more from pre- to post test. Ultimately, researchers should approach test equating based on their theoretical stance on Classical Test Theory and IRT and the respective assumptions. Regardless of the approach or method, test equating requires a representative sample of sufficient size. With small sample sizes, the application of a range of equating approaches can expose item and test features for review, inform interpretation, and identify paths for improving instruments for future study.Keywords: effectiveness, equipercentile equating, IRT, learning games, linear equating, mean-sigma equating
Procedia PDF Downloads 19211588 Customer Relationship Management - “Is It a Myth or a Reality in Indian Consumer Context”
Authors: Manish Manohar Hingorani
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The purpose of the research is to find out the level of understanding, adoption, and implementation of CRM in Indian Businesses, either product/ service and the processes which should be followed to ensure minimal to no customer churn and further enhance loyalty. The study used comprehensive qualitative interviews of 36 respondents across mid and senior-level management in product and services organizations of Indian origin. The findings of the study exhibit a gap between the understanding, adoption and implementation of CRM in the Indian context. Different Industries have attributed different levels of understanding, adoption, and limited implementation studies on CRM to the Indian context exists in different industries, but studies related to the consequences of not understanding the true meaning of CRM at the grass root level and further than on non-adoption and non-implementation will have an adverse effect on the customer loyalty, and customer satisfaction leading to customer churn. As this was a qualitative approach, the analysis was content-based and discourse based. The responses were taken from mid to very-senior management decision-makers in organizations of Indian origin.Keywords: customer relationship management, Indian consumer, customer loyalty, customer experience, customer satisfaction
Procedia PDF Downloads 9511587 Assess and Improve Building Energy Efficiency– a Case Study on the Office of Research and Graduate Studies at Qatar University
Authors: Mohamed Youssef
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The proliferation of energy consumption in the built environment has made energy efficiency and savings strategies a priority objective for energy policies in most countries. Qatar is a clear example, where it has initiated several programs and institutions to mitigate the overuse of electricity consumption and control the energy load of the building by following global standards and spreading awareness campaigns. A Case study on the Office of Research and Graduate Studies at Qatar University has been investigated in this paper. The paper studied the rating load of existing buildings before and after retrofitting by using Carrier’s Hourly Analysis Program (HAP). The performance of the building has increased especially after using the LED light system instead of fluorescent light with a low payback period. GINAN paint and green roof have shown a considerable contribution to the reduction of electrical load in the building. In comparison, the double HR window had the least effect on the reduction of electricity consumption.Keywords: energy conservation in Qatar, HAP, LED light, GINAN paint, green roof, double HR window
Procedia PDF Downloads 17211586 Evaluation of Site Laboratory Conditions Effect on Seismic Design Characteristics in Ramhormoz
Authors: Sayyed Yaghoub Zolfegharifar, Khairul Anuar Kassim, Hossein Khoramrooz, Khodayar Farhadiasl, Sadegh Jahan
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Iran is one of the world's seismically active countries so that it experiences many small to medium earthquakes annually and a large earthquake every ten years. Due to seism tectonic conditions and special geographical and climatic position, Iran has the potential to create numerous severe earthquakes. Therefore, seismicity studies and seismic zonation of seismic zones of the country are necessary. In this article, the effect of local site conditions on the characteristics of seismic design in Rahmormoz will be examined. After analyzing the seismic hazard for Rahmormoz through deterministic and statistical methods and preparing the necessary geotechnical models based on available data, the ground response will be analyzed for different parts of the city based on four inputs and acceleration level estimated for bedrock through the equivalent linear method and by means of Deep Soil program. Finally, through the analysis of the obtained results, the seismic profiles of the ground surface for different parts of the city will be presented.Keywords: seismic microzonation, ground response, resonance spectrum, period, site conditions
Procedia PDF Downloads 34811585 Resolving Partisan Conflict: A Dialectical Approach
Authors: Michael F. Mascolo
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Western democratic traditions are being strained. Western nations are losing the common agonistic ground needed to engage in traditional forms of democracy – adversarial debate, voting, and the peaceful transfer of power. Political polarization among party elites has become commonplace. Because it seeks to resolve conflict through the integration of opposites, a dialectical approach to resolving partisan conflict offers the promise of helping political partisans bridge ideological divides. This paper contains an analysis of dialectical engagement as a collaborative alternative to adversarial politics. Dialectical engagement involves two broad phases: collaborative political problem-solving and dialectical problem-solving. The paper contains a description of an 18-month longitudinal study assessing the effectiveness of dialectical engagement as a method for bridging divides on contentious socio-political issues. The study shows how dialectical engagement produced dramatic consensus among a small group of individuals from different political orientations as they worked together to resolve the issue of capital punishment.Keywords: collaborative democracy, dialectical thinking, capital punishment, partisan conflict
Procedia PDF Downloads 7111584 Remote Sensing of Urban Land Cover Change: Trends, Driving Forces, and Indicators
Authors: Wei Ji
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This study was conducted in the Kansas City metropolitan area of the United States, which has experienced significant urban sprawling in recent decades. The remote sensing of land cover changes in this area spanned over four decades from 1972 through 2010. The project was implemented in two stages: the first stage focused on detection of long-term trends of urban land cover change, while the second one examined how to detect the coupled effects of human impact and climate change on urban landscapes. For the first-stage study, six Landsat images were used with a time interval of about five years for the period from 1972 through 2001. Four major land cover types, built-up land, forestland, non-forest vegetation land, and surface water, were mapped using supervised image classification techniques. The study found that over the three decades the built-up lands in the study area were more than doubled, which was mainly at the expense of non-forest vegetation lands. Surprisingly and interestingly, the area also saw a significant gain in surface water coverage. This observation raised questions: How have human activities and precipitation variation jointly impacted surface water cover during recent decades? How can we detect such coupled impacts through remote sensing analysis? These questions led to the second stage of the study, in which we designed and developed approaches to detecting fine-scale surface waters and analyzing coupled effects of human impact and precipitation variation on the waters. To effectively detect urban landscape changes that might be jointly shaped by precipitation variation, our study proposed “urban wetscapes” (loosely-defined urban wetlands) as a new indicator for remote sensing detection. The study examined whether urban wetscape dynamics was a sensitive indicator of the coupled effects of the two driving forces. To better detect this indicator, a rule-based classification algorithm was developed to identify fine-scale, hidden wetlands that could not be appropriately detected based on their spectral differentiability by a traditional image classification. Three SPOT images for years 1992, 2008, and 2010, respectively were classified with this technique to generate the four types of land cover as described above. The spatial analyses of remotely-sensed wetscape changes were implemented at the scales of metropolitan, watershed, and sub-watershed, as well as based on the size of surface water bodies in order to accurately reveal urban wetscape change trends in relation to the driving forces. The study identified that urban wetscape dynamics varied in trend and magnitude from the metropolitan, watersheds, to sub-watersheds in response to human impacts at different scales. The study also found that increased precipitation in the region in the past decades swelled larger wetlands in particular while generally smaller wetlands decreased mainly due to human development activities. These results confirm that wetscape dynamics can effectively reveal the coupled effects of human impact and climate change on urban landscapes. As such, remote sensing of this indicator provides new insights into the relationships between urban land cover changes and driving forces.Keywords: urban land cover, human impact, climate change, rule-based classification, across-scale analysis
Procedia PDF Downloads 30811583 Linkages between Climate Change, Agricultural Productivity, Food Security and Economic Growth
Authors: Jihène Khalifa
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This study analyzed the relationships between Tunisia’s economic growth, food security, agricultural productivity, and climate change using the ARDL model for the period from 1990 to 2022. The ARDL model reveals a positive correlation between economic growth and lagged agricultural productivity. Additionally, the vector autoregressive (VAR) model highlights the beneficial impact of lagged agricultural productivity on economic growth and the negative effect of rainfall on economic growth. Granger causality analysis identifies unidirectional relationships from economic growth to agricultural productivity, crop production, food security, and temperature variations, as well as from temperature variations to crop production. Furthermore, a bidirectional causality is established between crop production and food security. The study underscores the impact of climate change on crop production and suggests the need for adaptive strategies to mitigate these climate effects.Keywords: economic growth, climate change, agriculture, ARDL, Granger causality, VAR
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