Search results for: new process model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 27938

Search results for: new process model

8708 The Interrelations between Niemeyer’s Works and the Concept of Typology: A Computer Based Analysis of Form and Structure

Authors: Aline M. C. Santoro, João C. Pantoja, Eduardo P. Rossetti

Abstract:

While the aim of the modernist movement was to deny known typology, the creation of a new formal language also gave it new meaning, which was now related to Form. This is specifically true in the modern capital of Brazil, where Niemeyer sought to demonstrate the manner in which the new materials available, such as reinforced concrete, were able to produce innovative forms. With this study, we aim to demonstrate the relationship between Niemeyer’s forms and the topological typology known as tessellation, through the presentation of two case studies, the Monument to Caxias and the Saint George Orthodox Church. At a first glance, our purpose is to present the definition of Form, especially with relationship to the works of Niemeyer, seeking to identify in them the concepts presented by Moussavi. Afterwards, we will use a computer-based approach to study and model the forms of two of his buildings with the McNeel Rhinoceros program, where, with the aid of diagrams and renderings, we will be able to clearly and legibly represent their organic forms and further understand their structural systems. When we recognise the concept of typology as a starting point for structural form, it can be concluded that the case studies presented here are encompassed by the typology presented by Moussavi since they derive from his basic structural systems.

Keywords: form, Niemeyer, structure, typology, topology

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8707 Children's Participation in the Everyday Life of the Early Childhood Institution - Action Research

Authors: lidija Vujičić, Akvilina Čamber Tambolas

Abstract:

The increasinginterest of ECCE policyandpractice in the issue of children'sparticipation in theirownlivesis a consequence of the changingimage of the childand the shift in focus to thechild as anactive participant in socio-culturalrealityinstead of theearlierfocus on thechild'sindividual development.TheConvention on the Rights of theChild (1989) stronglysupportstheimage of thechild as a competent participant in education - capable of formingopinions, withtheright to expressthemselves on allmattersaffectingthe mand with the right to haveadultsaroundthemrespectthis. Notwithstandingthecontemporaryparadigm of ECCE, however, achievements in thisarea are still in theirinfancy. This is evident in thepractices of ECCE, whereearlyyearsandpre-schoolchildren are stillseen as users of systemsandservicesratherthanagents of change in theirsocialcommunities. Recent literature identifiestheneed for lifelong, continuouslearning of preschoolteachersthroughresearchintotheirownpedagogicalpractice as aneffectiveway of bridgingthegapbetweentheoryandpracticeandcontinuouslyimprovingthequality of ECCE institutions. Notwithstandingthecontemporaryparadigm of ECCE, however, achievements in thisarea are still in theirinfancy. Recent literature identifiestheneed for lifelong, continuouslearning of preschoolteachersthroughresearchintotheirownpedagogicalpractice as aneffectiveway bridgingthegapbetweentheoryandpracticeandcontinuouslyimprovingthequality of ECCE institutions. Thispaperpresentstheprocess of actionresearchaimed at increasingchildren'sparticipation in (co-)designingthekindergartencurriculumandparticipation in decision-making on issuesaffectingtheirstay in theinstitution. Thisactionresearchtook place in 2 facilities of theinstitution ECCE - DV Rijeka. In thisresearchparticipated 5 preschoolteachersworking in 4 pedagogicalgroups, where childrenfrom 2 to 7 yearsold are enrolled. Also, the process of development of reflexivepractice of preschoolteacherswhoparticipated in thisresearchispresented.

Keywords: action research, co-construction of curriculum, participation of children, reflexive practice

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8706 Implementing Service Innovation in Public Transport Sector: Drivers and Challenges

Authors: Chaoren Lu

Abstract:

Public policy is playing as one driving force that influencing service innovation implementation in public sector. However, public policy implications cannot be automatically derived from the analyses of innovation issues, and there lacks of researches about the influences of public policy onto innovation. Moreover, innovation in service system is hard to predictable and whether policy encourages or hidden innovation is still lack of study. Especially, by given the context that multiple actors are active involving within the service delivery process in public transport sector, the complex driving forces and challenges are emerged towards the service operation. This study is aim to analysis the service innovation practices within service operating organizations to understand the drivers and challenges of service operation based on policy requirements, and where the innovation idea generating from. The case studies of Changzhou Transit Group and Nanjing Jiangnan Public Transit Group will be launched. This paper reveals the ambidexterity between top-down and bottom-up demands within the public transport service operating organizations contribute to the innovation ideas. Meanwhile, it contributes to the understanding of fundamental elements of service innovation is the new relationship creation and new way of sharing knowledge. The policy contributes to the trigger of creation of such relationship. The research question is: what are the sources of service innovation practices in local public transport system in China in in facing the policy implementation?

Keywords: public value, service innovation, public transport service, China

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8705 Improving Student Programming Skills in Introductory Computer and Data Science Courses Using Generative AI

Authors: Genady Grabarnik, Serge Yaskolko

Abstract:

Generative Artificial Intelligence (AI) has significantly expanded its applicability with the incorporation of Large Language Models (LLMs) and become a technology with promise to automate some areas that were very difficult to automate before. The paper describes the introduction of generative Artificial Intelligence into Introductory Computer and Data Science courses and analysis of effect of such introduction. The generative Artificial Intelligence is incorporated in the educational process two-fold: For the instructors, we create templates of prompts for generation of tasks, and grading of the students work, including feedback on the submitted assignments. For the students, we introduce them to basic prompt engineering, which in turn will be used for generation of test cases based on description of the problems, generating code snippets for the single block complexity programming, and partitioning into such blocks of an average size complexity programming. The above-mentioned classes are run using Large Language Models, and feedback from instructors and students and courses’ outcomes are collected. The analysis shows statistically significant positive effect and preference of both stakeholders.

Keywords: introductory computer and data science education, generative AI, large language models, application of LLMS to computer and data science education

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8704 Sectoral Energy Consumption in South Africa and Its Implication for Economic Growth

Authors: Kehinde Damilola Ilesanmi, Dev Datt Tewari

Abstract:

South Africa is in its post-industrial era moving from the primary and secondary sector to the tertiary sector. The study investigated the impact of the disaggregated energy consumption (coal, oil, and electricity) on the primary, secondary and tertiary sectors of the economy between 1980 and 2012 in South Africa. Using vector error correction model, it was established that South Africa is an energy dependent economy, and that energy (especially electricity and oil) is a limiting factor of growth. This implies that implementation of energy conservation policies may hamper economic growth. Output growth is significantly outpacing energy supply, which has necessitated load shedding. To meet up the excess energy demand, there is a need to increase the generating capacity which will necessitate increased investment in the electricity sector as well as strategic steps to increase oil production. There is also need to explore more renewable energy sources, in order to meet the growing energy demand without compromising growth and environmental sustainability. Policy makers should also pursue energy efficiency policies especially at sectoral level of the economy.

Keywords: causality, economic growth, energy consumption, hypothesis, sectoral output

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8703 Numerical Study of Off-Design Performance of a Highly Loaded Low Pressure Turbine Cascade

Authors: Shidvash Vakilipour, Mehdi Habibnia, Rouzbeh Riazi, Masoud Mohammadi, Mohammad H. Sabour

Abstract:

The flow field passing through a highly loaded low pressure (LP) turbine cascade is numerically investigated at design and off-design conditions. The Field Operation And Manipulation (OpenFOAM) platform is used as the computational Fluid Dynamics (CFD) tool. Firstly, the influences of grid resolution on the results of k-ε, k-ω, and LES turbulence models are investigated and compared with those of experimental measurements. A numerical pressure under-shoot is appeared near the end of blade pressure surface which is sensitive to grid resolution and flow turbulence modeling. The LES model is able to resolve separation on a coarse and fine grid resolutions. Secondly, the off-design flow condition is modeled by negative and positive inflow incidence angles. The numerical experiments show that a separation bubble generated on blade pressure side is predicted by LES. The total pressure drop is also been calculated at incidence angle between -20◦ and +8◦. The minimum total pressure drop is obtained by k-ω and LES at the design point.

Keywords: low pressure turbine, off-design performance, openFOAM, turbulence modeling, flow separation

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8702 Effects Induced by Dispersion-Promoting Cylinder on Fiber-Concentration Distributions in Pulp Suspension Flows

Authors: M. Sumida, T. Fujimoto

Abstract:

Fiber-concentration distributions in pulp liquid flows behind dispersion promoters were experimentally investigated to explore the feasibility of improving operational performance of hydraulic headboxes in papermaking machines. The proposed research was performed in the form of a basic test conducted on a screen-type model comprising a circular cylinder inserted within a channel. Tests were performed using pulp liquid possessing fiber concentrations ranging from 0.3-1.0 wt% under different flow velocities of 0.016-0.74 m/s. Fiber-concentration distributions were measured using the transmitted light attenuation method. Obtained test results were analyzed, and the influence of the flow velocities on wake characteristics behind the cylinder has been investigated with reference to findings of our preceding studies concerning pulp liquid flows in straight channels. Changes in fiber-concentration distribution along the flow direction were observed to be substantially large in the section from the cylinder to four times its diameter downstream of its centerline. Findings of this study provide useful information concerning the development of hydraulic headboxes.

Keywords: dispersion promoter, fiber-concentration distribution, hydraulic headbox, pulp liquid flow

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8701 Finite Element Analysis of Oil-Lubricated Elliptical Journal Bearings

Authors: Marco Tulio C. Faria

Abstract:

Fixed-geometry hydrodynamic journal bearings are one of the best supporting systems for several applications of rotating machinery. Cylindrical journal bearings present excellent load-carrying capacity and low manufacturing costs, but they are subjected to the oil-film instability at high speeds. An attempt of overcoming this instability problem has been the development of non-circular journal bearings. This work deals with an analysis of oil-lubricated elliptical journal bearings using the finite element method. Steady-state and dynamic performance characteristics of elliptical bearings are rendered by zeroth- and first-order lubrication equations obtained through a linearized perturbation method applied on the classical Reynolds equation. Four-node isoparametric rectangular finite elements are employed to model the bearing thin film flow. Curves of elliptical bearing load capacity and dynamic force coefficients are rendered at several operating conditions. The results presented in this work demonstrate the influence of the bearing ellipticity on its performance at different loading conditions.

Keywords: elliptical journal bearings, non-circular journal bearings, hydrodynamic bearings, finite element method

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8700 Metallurgical Analysis of Surface Defect in Telescopic Front Fork

Authors: Souvik Das, Janak Lal, Arthita Dey, Goutam Mukhopadhyay, Sandip Bhattacharya

Abstract:

Telescopic Front Fork (TFF) used in two wheelers, mainly motorcycle, is made from high strength steel, and is manufactured by high frequency induction welding process wherein hot rolled and pickled coils are used as input raw material for rolling of hollow tubes followed by heat treatment, surface treatment, cold drawing, tempering, etc. The final application demands superior quality TFF tubes w.r.t. surface finish and dimensional tolerances. This paper presents the investigation of two different types of failure of fork during operation. The investigation consists of visual inspection, chemical analysis, characterization of microstructure, and energy dispersive spectroscopy. In this paper, comprehensive investigations of two failed tube samples were investigated. In case of Sample #1, the result revealed that there was a pre-existing crack, known as hook crack, which leads to the cracking of the tube. Metallographic examination exhibited that during field operation the pre-existing hook crack was surfaced out leading to crack in the pipe. In case of Sample #2, presence of internal oxidation with decarburised grains inside the material indicates origin of the defect from slab stage.

Keywords: telescopic front fork, induction welding, hook crack, internal oxidation

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8699 Analysis of Cannabinoid and Cannabidiol Affinity with GABRA1

Authors: Hamid Hossein Khezri, Afsaneh Javdani-Mallak

Abstract:

Fast inhibitory neurotransmission in the mammalian nervous system is largely mediated by GABAA receptors, chloride-selective members of the superfamily of pentameric Cys-loop receptors. Cannabidiol (CBD) is one of the members of cannabinoid compounds found in cannabis. CBD and Cannabinol (CBN), as the other extract of plant Cannabis, were able to reduce myofascial pain in rats with immunosuppressive and anti-inflammatory activities. In this study, we accomplished protein-protein BLAST and the sequence was found to be for Gamma-aminobutyric acid receptor subunit alpha-1 (GBRA1) chain A and its 3D structure was subsequently downloaded from Protein Data Bank. The structures of the ligands cannabinol and cannabidiol were obtained from PubChem. After a necessary process of the obtained files, AutoDock Vina was used to performing molecular docking. Docking between the ligands and GBRA1 chain A revealed that cannabinol has a higher affinity to GBRA1 (binding energy = -7.5 kcal/mol) compared to cannabidiol (binding energy = -6.5 kcal/mol). Furthermore, cannabinol seems to be able to interact with 10 residues of the protein, out of which 3 are in the neurotransmitter-gated ion-channel transmembrane domain of GBRA1, whereas cannabidiol interacts with two other residues. Although the results of this project do not indicate the activating /or inhibitory capability of the studied compounds, it suggests that cannabinol can act as a relatively strong ligand for GBRA1.

Keywords: protein-ligand docking, cannabinol, cannabidiol, GBRA1

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8698 Mining and Ecological Events and its Impact on the Genesis and Geo-Distribution of Ebola Outbreaks in Africa

Authors: E Tambo, O. O. Olalubi, E. C. Ugwu, J. Y. Ngogang

Abstract:

Despite the World Health Organization (WHO) declaration of international health emergency concern, the status quo of responses and efforts to stem the worst-recorded Ebola epidemic Ebola outbreak is still precariously inadequate in most of the affected in West. Mining natural resources have been shown to play a key role in both motivating and fuelling ethnic, civil and armed conflicts that have plagued a number of African countries over the last decade. Revenues from the exploitation of natural resources are not only used in sustaining the national economy but also armies, personal enrichment and building political support. Little is documented on the mining and ecological impact on the emergence and geographical distribution of Ebola in Africa over time and space. We aimed to provide a better understanding of the interconnectedness among issues of mining natural, resource management, mining conflict and post-conflict on Ebola outbreak and how wealth generated from abundant natural resources could be better managed in promoting research and development towards strengthening environmental, socioeconomic and health systems sustainability on Ebola outbreak and other emerging diseases surveillance and responses systems prevention and control, early warning alert, durable peace and sustainable development rather than to fuel conflicts, resurgence and emerging diseases epidemics in the perspective of community and national/regional approach. Our results showed the first assessment of systematic impact of all major minerals conflict events diffusion over space and time and mining activities on nine Ebola genesis and geo-distribution in affected countries across Africa. We demonstrate how, where and when mining activities in Africa increase ecological degradation, conflicts at the local level and then spreads violence across territory and time by enhancing the financial capacities of fighting groups/ethnics and diseases onset. In addition, led process of developing minimum standards for natural resource governance; improving governmental and civil society capacity for natural resource management, including the strengthening of monitoring and enforcement mechanisms; understanding the post-mining and conflicts community or national reconstruction and rehabilitation programmes in strengthening or developing community health systems and regulatory mechanisms. In addition the quest for the control over these resources and illegal mining across the landscape forest incursion provided increase environmental and ecological instability and displacement and disequilibrium, therefore affecting the intensity and duration of mining and conflict/wars and episode of Ebola outbreaks over time and space. We highlight the key findings and lessons learnt in promoting country or community-led process in transforming natural resource wealth from a peace liability to a peace asset. The imperative necessity for advocacy and through facilitating intergovernmental deliberations on critical issues and challenges affecting Africa community transforming exploitation of natural resources from a peace liability to outbreak prevention and control. The vital role of mining in increasing government revenues and expenditures, equitable distribution of wealth and health to all stakeholders, in particular local communities requires coordination, cooperative leadership and partnership in fostering sustainable developmental initiatives from mining context to outbreak and other infectious diseases surveillance responses systems in prevention and control, and judicious resource management.

Keywords: mining, mining conflicts, mines, ecological, Ebola, outbreak, mining companies, miners, impact

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8697 Synthesis of Green Silver Nanoparticles with Aqueous Extract of Glycyrrhiza glabra and Its Characterization

Authors: Mandeep Kataria, Ankita Thakur

Abstract:

Glycyrrhiza glabra grows in the sub- tropical and warm temperate regions of the world, in Mediterranean countries and China, America, Europe, Asia and Australia. It grows in areas with sunny, dry and hot climates. It has numerous medicinal properties like it is used to cure Peptic Ulcers, Canker sores, Eczema, Indigestion and Upper Respiratory Infections. Biosynthetic methods such as plant extract have emerged as a simple and viable alternative to more complex chemical synthetic procedures to obtain nanomaterials. Extract from plant may act both as reducing and capping agents in silver nanoparticles synthesis. In the present work, Green Silver nanoparticles were successfully formulated from bioreduction of silver nitrate solutions using Glycyrrhiza glabra root extract. These Green Silver nanoparticles have been appropriately characterized using Visible spectroscopy, colour change. The Antimicrobial activity was done by Agar disc diffusion assay. AgNPs were developed by using aqueous root extract of Glycyrrhiza glabra, which acts as a reducing as well as stabilizing agent. The green synthetic method is a fast, low cost and eco-friendly process in the field of nanotechnology. The study revealed that the green-synthesized silver nanoparticle provides a promising approach for antimicrobial activity.

Keywords: Glycyrrhiza glabra, nanoparticles, antimicrobial activity, aqueous extract

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8696 Experimental Study on Using the Aluminum Sacrificial Anode as a Cathodic Protection for Marine Structures

Authors: A. Radwan, A. Elbatran, A. Mehanna, M. Shehadeh

Abstract:

The corrosion is natural chemical phenomenon that is applied in many engineering structures. Hence, it is one of the important topics to study in the engineering research. Ship and offshore structures are most exposed to corrosion due to the presence of corrosive medium of air and the seawater. Consequently, investigation of the corrosion behavior and properties over ship and offshore hulls is one of the important topics to study in the marine engineering research. Using sacrificial anode is the most popular solution for protecting marine structures from corrosion. Hence, this research investigates the extent of corrosion between the composite ship model and relative velocity of water, along with the sacrificial aluminum anode consumption and its degree of protection in seawater. In this study, the consumption rate of sacrificial aluminum anode with respect to relative velocity at different Reynold’s numbers was studied experimentally, and it was found that, the degree of cathodic protection represented by the cathode potential at a given distance from the aluminum anode was decreased slightly with increment of the relative velocity.

Keywords: corrosion, Reynold's numbers, sacrificial anode, velocity

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8695 Indium-Gallium-Zinc Oxide Photosynaptic Device with Alkylated Graphene Oxide for Optoelectronic Spike Processing

Authors: Seyong Oh, Jin-Hong Park

Abstract:

Recently, neuromorphic computing based on brain-inspired artificial neural networks (ANNs) has attracted huge amount of research interests due to the technological abilities to facilitate massively parallel, low-energy consuming, and event-driven computing. In particular, research on artificial synapse that imitate biological synapses responsible for human information processing and memory is in the spotlight. Here, we demonstrate a photosynaptic device, wherein a synaptic weight is governed by a mixed spike consisting of voltage and light spikes. Compared to the device operated only by the voltage spike, ∆G in the proposed photosynaptic device significantly increased from -2.32nS to 5.95nS with no degradation of nonlinearity (NL) (potentiation/depression values were changed from 4.24/8 to 5/8). Furthermore, the Modified National Institute of Standards and Technology (MNIST) digit pattern recognition rates improved from 36% and 49% to 50% and 62% in ANNs consisting of the synaptic devices with 20 and 100 weight states, respectively. We expect that the photosynaptic device technology processed by optoelectronic spike will play an important role in implementing the neuromorphic computing systems in the future.

Keywords: optoelectronic synapse, IGZO (Indium-Gallium-Zinc Oxide) photosynaptic device, optoelectronic spiking process, neuromorphic computing

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8694 Navigating the Legal Seas: The Freedom to Choose Applicable Law in Tort

Authors: Sara Vora (Hoxha)

Abstract:

An essential feature of any international lawsuit is the ability of the parties to pick the law that would apply in the event of a tort claim. This option to choose the law to use in tort cases is based on Article 14 and 4/3 of the Rome II Regulation. The purpose of this article is to examine the boundaries of this freedom, as well as its relevance in international legal disputes. The article opens with a brief introduction to the basics of tort law. After a short introduction, the article demonstrates why Article 14 and 4/3 of the Rome II Regulation are so crucial to the right to select appropriate law in tort cases. The notion of the right to select the law to use in tort cases is examined, along with its breadth and possible restrictions. The article presents case studies to demonstrate how the right to select relevant law in tort might be put into practise. Case results and the judges' rationales for their rulings are examined. The possible influence of the right to select applicable law in tort on the process of harmonisation is also explored in this study. The results are summarised and the primary research question is addressed in the last section of the paper. In conclusion, the parties' ability to pick the law that rules their dispute via the freedom to choose relevant law in tort is a crucial feature of cross-border litigation. Despite certain restrictions, this freedom is nevertheless an important part of the legal structure that governs international conflicts.

Keywords: applicable law, tort, Rome II regulation, freedom to choose, cross-border litigation, harmonization of tort law

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8693 Cultural Impact on Fairness Perception of Inequality: A Study on People With Chinese Roots Living in Germany

Authors: Yanping He-Ulbricht, Marc Oliver Rieger

Abstract:

Based on survey data collected from people with Chinese roots living in Germany, this paper examines the impact of assimilation degree and language priming (Chinese or German) on individuals’ perceived fairness of economic and social differences and their attitude towards these. The results show that both the language used and the length of time spent in a foreign culture have a significant impact. Subjects who had spent less than 10 years in Germany demonstrated a higher readiness to accept government intervention in markets with price limits than those who had lived there longer. Subjects who were asked and answered in German perceived the current economic situation as less fair and were also less inclined to accept inequality, even when it leads to a Pareto improvement. While the difference in fairness perception of inequality was a cultural effect, the difference in attitudes towards government intervention was rather a result of learning process. The findings imply that both learning processes of individuals and culture play an important role in perception and preferences regarding social and economic differences.

Keywords: assimilation, bilingualism, cross-cultural comparison, income inequality, language priming, price fairness

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8692 Enablers of Total Quality Management for Social Enterprises: A Study of UAE Social Organizations

Authors: Farhat Sultana

Abstract:

Originality: TQM principles are considered the tools to enhance organizational performance for most organizations. The paper contributes to the literature on the social enterprise because social organizations are still far behind in implementing TQM as compared to other private, public, and nonprofit organizations. Study design: The study is based on the data and information provided by two case studies and one focus group of social enterprises. Purpose: The purpose of the study is to get a deep understating of TQM implementation and to recognize the enablers of TQM in social enterprises that enhance the organizational performance of social enterprises located in UAE. Findings: As per the findings of the study, key enablers of Total Quality management in the case enterprises are leadership support, strategic approach for quality, continuous improvement, process improvement, employee empowerment and customer focus practices, though some inhibitors for TQM implementation such as managerial structure for quality assurance and performance appraisal mechanism are also pointed out by the study. Research limitations: The study findings are only based on two case studies and one focus group, which is not enough to generalize the findings to all social organizations. Practical Implications: Identified TQM enablers can help management to implement TQM successfully in social enterprises. Social implications: The study provides enabling path for Social enterprises to implement TQM to seek quality output to build a better society.

Keywords: TQM, social enterprise, enablers of TQM, UAE

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8691 Global Mittag-Leffler Stability of Fractional-Order Bidirectional Associative Memory Neural Network with Discrete and Distributed Transmission Delays

Authors: Swati Tyagi, Syed Abbas

Abstract:

Fractional-order Hopfield neural networks are generally used to model the information processing among the interacting neurons. To show the constancy of the processed information, it is required to analyze the stability of these systems. In this work, we perform Mittag-Leffler stability for the corresponding Caputo fractional-order bidirectional associative memory (BAM) neural networks with various time-delays. We derive sufficient conditions to ensure the existence and uniqueness of the equilibrium point by using the theory of topological degree theory. By applying the fractional Lyapunov method and Mittag-Leffler functions, we derive sufficient conditions for the global Mittag-Leffler stability, which further imply the global asymptotic stability of the network equilibrium. Finally, we present two suitable examples to show the effectiveness of the obtained results.

Keywords: bidirectional associative memory neural network, existence and uniqueness, fractional-order, Lyapunov function, Mittag-Leffler stability

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8690 Nanostructure and Adhesion of Cement/Polymer Fiber Interfaces

Authors: Faezeh Shalchy

Abstract:

Concrete is the most used materials in the world. It is also one of the most versatile while complex materials which human have used for construction. However, concrete is weak in tension, over the past thirty years many studies were accomplished to improve the tensile properties of concrete (cement-based materials) using a variety of methods. One of the most successful attempts is to use polymeric fibers in the structure of concrete to obtain a composite with high tensile strength and ductility. Understanding the mechanical behavior of fiber reinforced concrete requires the knowledge of the fiber/matrix interfaces at the small scale. In this study, a combination of numerical simulations and experimental techniques have been used to study the nano structure of fiber/matrix interfaces. A new model for calcium-silicate-hydrate (C-S-H)/fiber interfaces is proposed based on Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) analysis. The adhesion energy between the C-S-H gel and 2 different polymeric fibers (polyvinyl alcohol and polypropylene) was numerically studied at the atomistic level since adhesion is one of the key factors in the design of fiber reinforced composites. The mechanisms of adhesion as a function of the nano structure of fiber/matrix interfaces are also studied and discussed.

Keywords: fiber-reinforced concrete, adhesion, molecular modeling

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8689 Study of Cavitation Phenomena Based on Flow Visualization Test in 3-Way Reversing Valve

Authors: Hyo Lim Kang, Tae An Kim, Seung Ho Han

Abstract:

A 3-way reversing valve has been used in automotive washing machines to remove remaining oil and dirt on machined engine and transmission blocks. It provides rapid and accurate changes of water flow direction without any precise control device. However, due to its complicated bottom-plug shape, a cavitation occurs in a wide range of the bottom-plug in a downstream. In this study, the cavitation index and POC (percent of cavitation) were used to evaluate quantitatively the cavitation phenomena occurring at the bottom-plug. An optimal shape design was carried out via parametric study for geometries of the bottom-plug, in which a simple CAE-model was used in order to avoid time-consuming CFD analysis and hard to achieve convergence. To verify the results of numerical analysis, a flow visualization test was carried out using a test specimen with a transparent acryl pipe according to ISA-RP75.23. The flow characteristics such as the cavitation occurring in the downstream were investigated by using a flow test equipment with valve and pump including a flow control system and high-speed camera.

Keywords: cavitation, flow visualization test, optimal shape design, percent of cavitation, reversing valve

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8688 Domain Adaptive Dense Retrieval with Query Generation

Authors: Rui Yin, Haojie Wang, Xun Li

Abstract:

Recently, mainstream dense retrieval methods have obtained state-of-the-art results on some datasets and tasks. However, they require large amounts of training data, which is not available in most domains. The severe performance degradation of dense retrievers on new data domains has limited the use of dense retrieval methods to only a few domains with large training datasets. In this paper, we propose an unsupervised domain-adaptive approach based on query generation. First, a generative model is used to generate relevant queries for each passage in the target corpus, and then, the generated queries are used for mining negative passages. Finally, the query-passage pairs are labeled with a cross-encoder and used to train a domain-adapted dense retriever. We also explore contrastive learning as a method for training domain-adapted dense retrievers and show that it leads to strong performance in various retrieval settings. Experiments show that our approach is more robust than previous methods in target domains that require less unlabeled data.

Keywords: dense retrieval, query generation, contrastive learning, unsupervised training

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8687 Simplifying Health Risk Assessment (HRA) and Its Operationalisation for Turnaround Activities

Authors: Thirumila Muthukamaru

Abstract:

The objective of a Health Risk Assessment (HRA) is to achieve a quality evaluation of risk assessments in a timely manner where adequate controls can be in place to protect workers health, especially during turnarounds where the exposure to health hazards is expected to rise during the performance of the many activities that take place, exposing workers to health risk. HRA development requires a competent team comprising experienced subject matter experts in the field, such as Industrial hygienists, Occupational Health Doctors, Turnaround Coordinators, Operation / Maintenance personnel, etc. The conventional way of conducting HRA is not only tedious and time-consuming but also less appreciated when it is not interpreted correctly, which may contribute to inadequate operationalization of it. Simplification can be the essence of timely intervention in managing health risks. This paper is intended as a sharing of the approach taken to simplify the methodology of developing the HRA report and operationalizing it. The approach includes developing a Generic HRA for turnaround activities to be used as a reference document and the empowerment of identified personnel through upskilling sessions to take up the role of facilitating HRA sessions. This empowerment is one of the key approaches towards the successful translation of the HRA into specific turnaround Job Hazard Analysis (JHA) that embed it in the Permit to Work (PTW) process. The approach used here increases awareness and compliance on HRA for turnaround activities through better interpretation and operationalization of the HRA report, adding value to the risk assessment for turnaround activities.

Keywords: industrial hygiene, health risk assessment, HRA, risk assessment

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8686 Statistical Analysis of Surface Roughness and Tool Life Using (RSM) in Face Milling

Authors: Mohieddine Benghersallah, Lakhdar Boulanouar, Salim Belhadi

Abstract:

Currently, higher production rate with required quality and low cost is the basic principle in the competitive manufacturing industry. This is mainly achieved by using high cutting speed and feed rates. Elevated temperatures in the cutting zone under these conditions shorten tool life and adversely affect the dimensional accuracy and surface integrity of component. Thus it is necessary to find optimum cutting conditions (cutting speed, feed rate, machining environment, tool material and geometry) that can produce components in accordance with the project and having a relatively high production rate. Response surface methodology is a collection of mathematical and statistical techniques that are useful for modelling and analysis of problems in which a response of interest is influenced by several variables and the objective is to optimize this response. The work presented in this paper examines the effects of cutting parameters (cutting speed, feed rate and depth of cut) on to the surface roughness through the mathematical model developed by using the data gathered from a series of milling experiments performed.

Keywords: Statistical analysis (RSM), Bearing steel, Coating inserts, Tool life, Surface Roughness, End milling.

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8685 Effect of Testing Device Calibration on Liquid Limit Assessment

Authors: M. O. Bayram, H. B. Gencdal, N. O. Fercan, B. Basbug

Abstract:

Liquid limit, which is used as a measure of soil strength, can be detected by Casagrande and fall-cone testing methods. The two methods majorly diverge from each other in terms of operator dependency. The Casagrande method that is applied according to ASTM D4318-17 standards may give misleading results, especially if the calibration process is not performed well. To reveal the effect of calibration for drop height and amount of soil paste placement in the Casagrande cup, a series of tests were carried out by multipoint method as it is specified in the ASTM standards. The tests include the combination of 6 mm, 8 mm, 10 mm, and 12 mm drop heights and under-filled, half-filled, and full-filled Casagrande cups by kaolinite samples. It was observed that during successive tests, the drop height of the cup deteriorated; hence the device was recalibrated before and after each test to provide the accuracy of the results. Besides, the tests by under-filled and full-filled samples for higher drop heights revealed lower liquid limit values than the lower drop heights revealed. For the half-filled samples, it was clearly seen that the liquid limit values didn’t change at all as the drop height increased, and this explains the function of standard specifications.

Keywords: calibration, casagrande cup method, drop height, kaolinite, liquid limit, placing form

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8684 Implementation of Problem-Based Learning (PBL) in the Classroom

Authors: Jarmon Sirigunna

Abstract:

The objective of this study were to investigate the success of the implementation of problem-based learning in classroom and to evaluate the level of satisfaction of Suan Sunandra Rajabhat University’s students who participated in the study. This paper aimed to study and focus on a university students survey conducted in Suan Sunandha Rajabhat University during January to March of 2014. The quota sampling was utilized to obtain the sample which included 60 students, 50 percent male and 50 percent female students. The pretest and posttest method was utilized. The findings revealed that the majority of respondents had gained higher knowledge after the posttest significantly. The respondents’ knowledge increased about 40 percent after the experiment. Also, the findings revealed the top three highest level of satisfaction as follows: 1) the proper roles of teacher and students, 2) the knowledge gained from the method of the problem-based learning, 3) the activities of the problem-based learning, 4) the interaction of students from the problem-based learning, and 5) the problem-based learning model. Also, the mean score of all categories was 4.22 with a standard deviation of 0.7435 which indicated that the level of satisfaction was high.

Keywords: implement, problem-based learning, satisfaction, university students

Procedia PDF Downloads 359
8683 Grading Histopathology Features of Graft-Versus-Host Disease in Animal Models; A Systematic Review

Authors: Hami Ashraf, Farid Kosari

Abstract:

Graft-versus-host disease (GvHD) is a common complication of allogeneic hematopoietic stem cell transplantation that can lead to significant morbidity and mortality. Histopathological examination of affected tissues is an essential tool for diagnosing and grading GvHD in animal models, which are used to study disease mechanisms and evaluate new therapies. In this systematic review, we identified and analyzed original research articles in PubMed, Scopus, Web of Science, and Google Scholar that described grading systems for GvHD in animal models based on histopathological features. We found that several grading systems have been developed, which vary in the tissues and criteria they assess, the severity scoring scales they use, and the level of detail they provide. Skin, liver, and gut are the most commonly evaluated tissues, but lung and thymus are also included in some systems. Our analysis highlights the need for standardized criteria and consistent use of grading systems to enable comparisons between studies and facilitate the translation of preclinical findings to clinical practice.

Keywords: graft-versus-host disease, GvHD, animal model, histopathology, grading system

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8682 Validation of Existing Index Properties-Based Correlations for Estimating the Soil–Water Characteristic Curve of Fine-Grained Soils

Authors: Karim Kootahi, Seyed Abolhasan Naeini

Abstract:

The soil-water characteristic curve (SWCC), which represents the relationship between suction and water content (or degree of saturation), is an important property of unsaturated soils. The conventional method for determining SWCC is through specialized testing procedures. Since these procedures require specialized unsaturated soil testing apparatus and lengthy testing programs, several index properties-based correlations have been developed for estimating the SWCC of fine-grained soils. There are, however, considerable inconsistencies among the published correlations and there is no validation study on the predictive ability of existing correlations. In the present study, all existing index properties-based correlations are evaluated using a high quality worldwide database. The performances of existing correlations are assessed both graphically and quantitatively using statistical measures. The results of the validation indicate that most of the existing correlations provide unacceptable estimates of degree of saturation but the most recent model appears to be promising.

Keywords: SWCC, correlations, index properties, validation

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8681 Measuring Entrepreneurship Intentions among Nigerian University Graduates: A Structural Equation Modeling Technique

Authors: Eunice Oluwakemi Chukwuma-Nwuba

Abstract:

Nigeria is a developing country with an increasing rate of graduate unemployment. This has triggered successive government administrations to promote the variety of programmes to address the situation. However, none of these efforts yielded the desired outcome. Accordingly, in 2006 the government included entrepreneurship module in the curriculum of universities as a compulsory general programme for all undergraduate courses. This is in the hope that the programme will help to promote entrepreneurial mind-set and new venture creation among graduates and as a result reduce the rate of graduate unemployment. The study explores the effectiveness of entrepreneurship education in promoting entrepreneurship. This study is significant in view of the endemic graduate unemployment in Nigeria and the social consequences such as youth restiveness and militancy. It is guided by the theory of planned behaviour. It employed the two-stage structural equation modelling (AMOS) to model entrepreneurial intentions as a function of innovative teaching methods, traditional teaching methods and culture Personal attitude and subjective norm are proposed to mediate the relationships between the exogenous and the endogenous variables. The first stage was tested using multi-group confirmatory factor analysis (MGCFA) framework to confirm that the two groups assign the same meaning to the scale items and to obtain goodness-of-fit indices. The multi-group confirmatory factor analysis included the tests of configural, metric and scalar invariance. With the attainment of full configural invariance and partial metric and scalar invariance, the second stage – the structural model was applied hypothesising that, the entrepreneurial intentions of graduates (respondents who have participated in the compulsory entrepreneurship programme) will be higher than those of undergraduates (respondents who are yet to participate in the programme). The study uses the quasi-experimental design. The samples comprised 409 graduates (experimental group) and 402 undergraduates (control group) from six federal universities in Nigeria. Our findings suggest that personal attitude is positively related with entrepreneurial intentions, largely confirming prior literature. However, unlike previous studies, our results indicate that subjective norm has significant direct and indirect impact on entrepreneurial intentions indicating that reference people of the participants have important roles to play in their decision to be entrepreneurial. Furthermore, unlike the assertions in prior studies, the result suggests that traditional teaching methods have indirect effect on entrepreneurial intentions supporting that since personal characteristics can change in an educational situation, an education purposively directed at entrepreneurship might achieve similar results if not better. This study has implication for practice and theory. The research extends to the theoretical understanding of the formation of entrepreneurial intentions and explains the role of the reference others in relation to how graduates perceive entrepreneurship. Further, the study adds to the body of knowledge on entrepreneurship education in Nigeria universities and provides a developing country perspective. It proposes further research in the exploration of entrepreneurship education and entrepreneurial intentions of graduates from across the country’s universities as necessary and imperative.

Keywords: entrepreneurship education, entrepreneurial intention, structural equation modeling, theory of planned behaviour

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8680 Teachers’ Personal and Professional Characteristics: How They Relate to Teacher-Student Relationships and Students’ Behavior

Authors: Maria Poulou

Abstract:

The study investigated how teachers’ self-rated Emotional Intelligence (EI), competence in implementing Social and Emotional Learning (SEL) skills and teaching efficacy relate to teacher-student relationships and students’ emotional and behavioral difficulties. Participants were 98 elementary teachers from public schools in central Greece. They completed the Self-Rated Emotional Intelligence Scale (SREIS), the Teacher SEL Beliefs Scale, the Teachers’ Sense of Efficacy Scale (TSES), the Student-Teacher Relationships Scale-Short Form (STRS-SF) and the Strengths and Difficulties Questionnaire (SDQ) for 617 of their students, aged 6-11 years old. Structural equation modeling was used to examine an exploratory model of the variables. It was demonstrated that teachers’ emotional intelligence, SEL beliefs and teaching efficacy were significantly related to teacher-student relationships, but they were not related to students’ emotional and behavioral difficulties. Rather, teachers’ perceptions of teacher-students relationships were significantly related to these difficulties. These findings and their implications for research and practice are discussed.

Keywords: emotional intelligence, social and emotional learning, teacher-student relationships, teaching efficacy

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8679 The Power of “Merkiavelli”: Representations of Angela Merkel in the Portuguese Press (2008-2015)

Authors: Ana Mouro, Ana Ramalheira

Abstract:

Since 1989, with the Fall of the Berlin Wall, Germany has undergone a profound restructuring political and economic process. When the Euro Crisis broke out, Germany was no longer the “sick man” of Europe. Instead, it had recovered its dominance as the strongest and wealthiest economy within the European Union. With the European Debt Crisis, that has been taking place in the European Union since the end of 2009, Germany´s Chancellor Angela Merkel has gained the power of deciding, so to say, on the fate of the debtor nations, but she neither stands for binding German commitments, nor refuses assistance. A debate on whether Merkel’s hesitation has been deliberated and used as a means of coercion has arisen on international print media, and the Portuguese Press has been no exception. This study, which was conducted by using news reporting, opinion articles, interviews and editorials, published in the Portuguese weekly Expresso and the daily Público, from 2008 to 2015, tries to show how Merkel’s hesitation, depicted in the press by the term “Merkiavelli”, was perceived in Portugal, a country that had to embrace the austerity measures, imposed by the European Central Bank, but defined under Angela Merkel´s leading role.

Keywords: Euro crisis, “Merkiavelli”, cultural studies, Portuguese quality press

Procedia PDF Downloads 235