Search results for: evolution mechanism
4512 The Mechanical Properties of In-Situ Consolidated Nanocrystalline Aluminum Alloys
Authors: Khaled M. Youssef, Sara I. Ahmed
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In this study, artifacts-free bulk nanocrystalline pure aluminum alloy samples were prepared through mechanical milling under ultra-high purity argon and at both liquid nitrogen and room temperatures. The nanostructure evolution during milling was examined using X-ray diffraction and transmission electron microscope techniques. The in-situ consolidated samples after milling exhibited an average grain size of 18 nm. The tensile properties of this novel material are reported in comparison with coarse-grained aluminum alloys. The 0.2% offset yield strength of the nanocrystalline aluminum was found to be 340 MPa. This value is at least one order of magnitude higher than that of the coarse-grained aluminum alloy. In addition to this extraordinarily high strength, the nanocrystalline aluminum showed a significant tensile ductility, with 6% uniform elongation and 11% elongation-to-failure. The transmission electron microscope observations in this study provide evidence of deformation twinning in the plastically deformed nanocrystalline aluminum. These results highlight a change of the deformation mechanism from a typical dislocation slip to twinning deformation induced by partial dislocation activities.Keywords: nanocrystalline, aluminum, strength, ductility
Procedia PDF Downloads 1734511 Evolution of Germany’s Feed-in Tariff Policy
Authors: Gaafar Muhammed, N. T. Ersoy
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The role of electricity in the economic development of any country is undeniable. The main goal of utilizing renewable sources in electricity generation, especially in the emerging countries, is to improve electricity access, economic development and energy sustainability. Germany’s recent transition from conventional to renewable energy technologies is overwhelming, this might not be associated with its abundant natural resources but owing to the policies in place. In line with the fast economic and technological developments recorded in recent years, Germany currently produces approximately 1059 GW of its energy from renewable sources. Hence, at the end of 2016, Germany is among the world leaders in terms of installed renewable energy capacity. As one of the most important factors that lead to renewable energy utilization in any nation is an effective policy, this study aims at examining the effect of policies on renewable energy (RE) development in Germany. Also, the study will focus on the evolution of the adopted feed-in tariff policies, as this evolution has affected the renewable energy capacity in Germany over a period of 15 years (2000 to 2015). The main contribution of the study is to establish a link between the feed-in tariff and the increase of RE in Germany’s energy mix. This is done by analyzing the characteristics of various feed-in tariff mechanisms adopted through the years. These characteristics include the feed-in-tariff rate, degression, special conditions, supported technology, etc. Then, the renewable energy development in Germany has been analyzed through the years along with the targets and the progress in reaching these targets. The study reveals that Germany’s renewable energy support policies (especially feed-in tariff) lead to several benefits and contribute towards the targets existing for renewable energy.Keywords: feed-in tariff, Germany, policy, penewable energy
Procedia PDF Downloads 2814510 Diachronic Evolution and Multifaceted Interpretation of City-Mountain Landscape Culture: From Ritualistic Divinity to Poetic Aesthetics
Authors: Junjie Fu
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This paper explores the cultural evolution of the "city-mountain" landscape in ancient Chinese cities, tracing its origins in the regional mountain and town division within the national system. It delves into the cultural archetype of "city-mountain" landscape divine imagery and its spatial characteristics, drawing from the spatial conception of mountain worship and divine order in the model of Kunlun and Penglai. Furthermore, it examines the shift from religious to daily life influences, leading to a poetic aesthetic turn in the "city-mountain" landscape. The paper also discusses the organizational structure of the "city-mountain" poetic landscape and its role as a space for enjoyment. By studying the cultural connotations, evolving relationships, and power mechanisms of the "city-mountain" landscape, this research provides theoretical insights for the construction and development of "city-mountain" landscapes and mountain cities.Keywords: city-mountain landscape, cultural image, divinity, landscape image, poetry
Procedia PDF Downloads 744509 Analyzing the Evolution of Polythiophene Nanoparticles Optically, Structurally, and Morphologically as a Sers (Surface-Enhanced Raman Spectroscopy) Sensor Pb²⁺ Detection in River Water
Authors: Temesgen Geremew
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This study investigates the evolution of polythiophene nanoparticles (PThNPs) as surface-enhanced Raman spectroscopy (SERS) sensors for Pb²⁺ detection in river water. We analyze the PThNPs' optical, structural, and morphological properties at different stages of their development to understand their SERS performance. Techniques like UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) are employed for characterization. The SERS sensitivity towards Pb²⁺ is evaluated by monitoring the peak intensity of a specific Raman band upon increasing metal ion concentration. The study aims to elucidate the relationship between the PThNPs' characteristics and their SERS efficiency for Pb²⁺ detection, paving the way for optimizing their design and fabrication for improved sensing performance in real-world environmental monitoring applications.Keywords: polythiophene, Pb2+, SERS, nanoparticles
Procedia PDF Downloads 434508 Investigation of Different Conditions to Detect Cycles in Linearly Implicit Quantized State Systems
Authors: Elmongi Elbellili, Ben Lauwens, Daan Huybrechs
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The increasing complexity of modern engineering systems presents a challenge to the digital simulation of these systems which usually can be represented by differential equations. The Linearly Implicit Quantized State System (LIQSS) offers an alternative approach to traditional numerical integration techniques for solving Ordinary Differential Equations (ODEs). This method proved effective for handling discontinuous and large stiff systems. However, the inherent discrete nature of LIQSS may introduce oscillations that result in unnecessary computational steps. The current oscillation detection mechanism relies on a condition that checks the significance of the derivatives, but it could be further improved. This paper describes a different cycle detection mechanism and presents the outcomes using LIQSS order one in simulating the Advection Diffusion problem. The efficiency of this new cycle detection mechanism is verified by comparing the performance of the current solver against the new version as well as a reference solution using a Runge-Kutta method of order14.Keywords: numerical integration, quantized state systems, ordinary differential equations, stiffness, cycle detection, simulation
Procedia PDF Downloads 524507 Review and Classification of the Indicators and Trends Used in Bridge Performance Modeling
Authors: S. Rezaei, Z. Mirzaei, M. Khalighi, J. Bahrami
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Bridges, as an essential part of road infrastructures, are affected by various deterioration mechanisms over time due to the changes in their performance. As changes in performance can have many negative impacts on society, it is essential to be able to evaluate and measure the performance of bridges throughout their life. This evaluation includes the development or the choice of the appropriate performance indicators, which, in turn, are measured based on the selection of appropriate models for the existing deterioration mechanism. The purpose of this article is a statistical study of indicators and deterioration mechanisms of bridges in order to discover further research capacities in bridges performance assessment. For this purpose, some of the most common indicators of bridge performance, including reliability, risk, vulnerability, robustness, and resilience, were selected. The researches performed on each index based on the desired deterioration mechanisms and hazards were comprehensively reviewed. In addition, the formulation of the indicators and their relationship with each other were studied. The research conducted on the mentioned indicators were classified from the point of view of deterministic or probabilistic method, the level of study (element level, object level, etc.), and the type of hazard and the deterioration mechanism of interest. For each of the indicators, a number of challenges and recommendations were presented according to the review of previous studies.Keywords: bridge, deterioration mechanism, lifecycle, performance indicator
Procedia PDF Downloads 1004506 Software Evolution Based Activity Diagrams
Authors: Zine-Eddine Bouras, Abdelouaheb Talai
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During the last two decades, the software evolution community has intensively tackled the software merging issue whose main objective is to merge in a consistent way different versions of software in order to obtain a new version. Well-established approaches, mainly based on the dependence analysis techniques, have been used to bring suitable solutions. These approaches concern the source code or software architectures. However, these solutions are more expensive due to the complexity and size. In this paper, we overcome this problem by operating at a high level of abstraction. The objective of this paper is to investigate the software merging at the level of UML activity diagrams, which is a new interesting issue. Its purpose is to merge activity diagrams instead of source code. The proposed approach, based on dependence analysis techniques, is illustrated through an appropriate case study.Keywords: activity diagram, activity diagram slicing, dependency analysis, software merging
Procedia PDF Downloads 3214505 Integrating Reactive Chlorine Species Generation with H2 Evolution in a Multifunctional Photoelectrochemical System for Low Operational Carbon Emissions Saline Sewage Treatment
Authors: Zexiao Zheng, Irene M. C. Lo
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Organic pollutants, ammonia, and bacteria are major contaminants in sewage, which may adversely impact ecosystems without proper treatment. Conventional wastewater treatment plants (WWTPs) are operated to remove these contaminants from sewage but suffer from high carbon emissions and are powerless to remove emerging organic pollutants (EOPs). Herein, we have developed a low operational carbon emissions multifunctional photoelectrochemical (PEC) system for saline sewage treatment to simultaneously remove organic compounds, ammonia, and bacteria, coupled with H2 evolution. A reduced BiVO4 (r-BiVO4) with improved PEC properties due to the construction of oxygen vacancies and V4+ species was developed for the multifunctional PEC system. The PEC/r-BiVO4 process could treat saline sewage to meet local WWTPs’ discharge standard in 40 minutes at 2.0 V vs. Ag/AgCl and completely degrade carbamazepine (one of the EOPs), coupled with significant evolution of H2. A remarkable reduction in operational carbon emissions was achieved by the PEC/r-BiVO4 process compared with large-scale WWTPs, attributed to the restrained direct carbon emissions from the generation of greenhouse gases. Mechanistic investigation revealed that the PEC system could activate chloride ions in sewage to generate reactive chlorine species and facilitate •OH production, promoting contaminants removal. The PEC system exhibited operational feasibility at different pH and total suspended solids concentrations and has outstanding reusability and stability, confirming its promising practical potential. The study combined the simultaneous removal of three major contaminants from saline sewage and H2 evolution in a single PEC process, demonstrating a viable approach to supplementing and extending the existing wastewater treatment technologies. The study generated profound insights into the in-situ activation of existing chloride ions in sewage for contaminants removal and offered fundamental theories for applying the PEC system in sewage remediation with low operational carbon emissions. The developed PEC system can fit well with the future needs of wastewater treatment because of the following features: (i) low operational carbon emissions, benefiting the carbon neutrality process; (ii) higher quality of the effluent due to the elimination of EOPs; (iii) chemical-free in the operation of sewage treatment; (iv) easy reuse and recycling without secondary pollution.Keywords: contaminants removal, H2 evolution, multifunctional PEC system, operational carbon emissions, saline sewage treatment, r-BiVO4 photoanodes
Procedia PDF Downloads 1504504 Omni: Data Science Platform for Evaluate Performance of a LoRaWAN Network
Authors: Emanuele A. Solagna, Ricardo S, Tozetto, Roberto dos S. Rabello
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Nowadays, physical processes are becoming digitized by the evolution of communication, sensing and storage technologies which promote the development of smart cities. The evolution of this technology has generated multiple challenges related to the generation of big data and the active participation of electronic devices in society. Thus, devices can send information that is captured and processed over large areas, but there is no guarantee that all the obtained data amount will be effectively stored and correctly persisted. Because, depending on the technology which is used, there are parameters that has huge influence on the full delivery of information. This article aims to characterize the project, currently under development, of a platform that based on data science will perform a performance and effectiveness evaluation of an industrial network that implements LoRaWAN technology considering its main parameters configuration relating these parameters to the information loss.Keywords: Internet of Things, LoRa, LoRaWAN, smart cities
Procedia PDF Downloads 1404503 Routing Protocol in Ship Dynamic Positioning Based on WSN Clustering Data Fusion System
Authors: Zhou Mo, Dennis Chow
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In the dynamic positioning system (DPS) for vessels, the reliable information transmission between each note basically relies on the wireless protocols. From the perspective of cluster-based routing protocols for wireless sensor networks, the data fusion technology based on the sleep scheduling mechanism and remaining energy in network layer is proposed, which applies the sleep scheduling mechanism to the routing protocols, considering the remaining energy of node and location information when selecting cluster-head. The problem of uneven distribution of nodes in each cluster is solved by the Equilibrium. At the same time, Classified Forwarding Mechanism as well as Redelivery Policy strategy is adopted to avoid congestion in the transmission of huge amount of data, reduce the delay in data delivery and enhance the real-time response. In this paper, a simulation test is conducted to improve the routing protocols, which turn out to reduce the energy consumption of nodes and increase the efficiency of data delivery.Keywords: DPS for vessel, wireless sensor network, data fusion, routing protocols
Procedia PDF Downloads 5174502 Evolution and Obstacles Encountered in the Realm of Sports Tourism in Pakistan
Authors: Muhammad Saleem
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Tourism stands as one of the swiftly expanding sectors globally, contributing to 10% of the overall worldwide GDP. It holds a vital role in generating income, fostering employment opportunities, alleviating poverty, facilitating foreign exchange earnings, and advancing intercultural understanding. This industry encompasses a spectrum of activities, encompassing transportation, communication, hospitality, catering, entertainment, and advertising. The objective of this study is to assess the evolution and obstacles encountered by sports tourism in Pakistan. In pursuit of this objective, relevant literature has been scrutinized, while data has been acquired from 60 respondents, employing a simple random sampling approach for analysis. The survey comprised close-ended inquiries directed towards all participants. Analytical tools such as mean, mode, median, graphs, and percentages have been employed for data analysis. The findings revealed through robust analysis, indicate that the mean, mode, and median tools consistently yield results surpassing the 70% mark, underscoring that heightened development within sports tourism significantly augments its progress. Effective governance demonstrates a favorable influence on sports tourism, with increased government-provided safety and security potentially amplifying its expansion, thus attracting a higher number of tourists and consequently propelling the growth of the sports tourism sector. This study holds substantial significance for both academic scholars and industry practitioners within Pakistan's tourism landscape, as previous explorations in this realm have been relatively limited.Keywords: obstacles-spots, evolution-tourism, sports-pakistan, sports-obstacles-pakistan
Procedia PDF Downloads 424501 Isolation and Characterization of Salt-Tolerance of Rhizobia under the Effects of Salinity
Authors: Sarra Sobti, Baelhadj Hamdi-Aïssa
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The bacteria of the soil, usually called rhizobium, have a considerable importance in agriculture because of their capacity to fix the atmospheric nitrogen in symbiosis with the plants of the family of legumes. The present work was to study the effect of the salinity on growth and nodulation of alfalfa-rhizobia symbiosis at different agricultural experimental sites in Ouargla. The experiment was conducted in 3 steps. The first one was the isolation and characterization of the Rhizobia; next, the evolution of the isolates tolerance to salinity at three levels of NaCl (6, 8,12 and 16 g/L); and the last step was the evolution of the tolerance on symbiotic characteristics. The results showed that the phenotypic characterizations behave practically as Rhizobia spp, and the effects of salinity affect the symbiotic process. The tolerance to high levels of salinity and the survival and persistence in severe and harsh desert conditions make these rhizobia highly valuable inoculums to improve productivity of the leguminous plants cultivated under extreme environments.Keywords: rhizobia, symbiosis, salinity, tolerance, nodulation, soil, Medicago sativa L.
Procedia PDF Downloads 3074500 Research on Routing Protocol in Ship Dynamic Positioning Based on WSN Clustering Data Fusion System
Authors: Zhou Mo, Dennis Chow
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In the dynamic positioning system (DPS) for vessels, the reliable information transmission between each note basically relies on the wireless protocols. From the perspective of cluster-based routing pro-tocols for wireless sensor networks, the data fusion technology based on the sleep scheduling mechanism and remaining energy in network layer is proposed, which applies the sleep scheduling mechanism to the routing protocols, considering the remaining energy of node and location information when selecting cluster-head. The problem of uneven distribution of nodes in each cluster is solved by the Equilibrium. At the same time, Classified Forwarding Mechanism as well as Redelivery Policy strategy is adopted to avoid congestion in the transmission of huge amount of data, reduce the delay in data delivery and enhance the real-time response. In this paper, a simulation test is conducted to improve the routing protocols, which turns out to reduce the energy consumption of nodes and increase the efficiency of data delivery.Keywords: DPS for vessel, wireless sensor network, data fusion, routing protocols
Procedia PDF Downloads 4504499 Collapse Capacity and Energy Absorption Mechanism of High Rise Steel Moment Frame Considering Aftershock Effects
Authors: Mohammadmehdi Torfehnejad, Serhan Sensoy
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Many structures sustain damage during a mainshock earthquake but undergo severe damage under aftershocks following the mainshock. Past researches have studied aftershock effects through different methodologies, but few structural systems have been evaluated for these effects. Collapse capacity and energy absorption mechanism of the Special Steel Moment Frame (SSMF) system is evaluated in this study, under aftershock earthquakes when prior damage is caused by the mainshock. A twenty-story building is considered in assessing the residual collapse capacity and energy absorption mechanism under aftershock excitation. In addition, various levels of mainshock damage are considered and reflected through two different response parameters. Aftershock collapse capacity is estimated using incremental dynamic analysis (IDA) applied following the mainshock. The study results reveal that the collapse capacity of high-rise structures undergoes a remarkable reduction for high level of mainshock damage. The energy absorption in the columns is decreased by increasing the level of mainshock damage.Keywords: seismic collapse, mainshock-aftershock effect, incremental dynamic analysis, energy absorption
Procedia PDF Downloads 1234498 Cyclic Voltammetric Investigations on Nickel Electrodeposition from Industrial Sulfate Electrolyte in Presence of Ca(II), Mg(II), Na(I) Ions
Authors: Udit Mohanty, Mari Lundstrom
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Electrochemical investigation by cyclic voltammetry was conducted to explore the polarization behavior of reactions occurring in nickel electrowinning in presence of cationic impurities such as Ca2+ (0-100 mg/L), Na+ (1-10 g/L) and Mg2+ (10-100 mg/L). A comparative study was devised between industrial and synthetic electrolytes to observe the shift in the nucleation overpotentials of nickel deposition, dissolution and hydrogen evolution reactions at the cathode and anode respectively. Significant polarization of cathodic reactions were observed with concentrations of Na ≥ 8g /L and Ca ≤ 40 mg /L in the synthetic electrolytes. Nevertheless, a progressive increase in the concentration of Ca, Mg and Na in the industrial electrolyte demonstrated a depolarization behavior in the cathodic reactions related to nickel deposition and/or hydrogen evolution. Synergistic effect of Ca with Mg and Na in both the industrial and synthetic electrolytes induced a notable depolarization effect, also reflected in the peak currents.Keywords: cationic impurities, cyclic voltammetry, electrowinning, nickel, polarization
Procedia PDF Downloads 2344497 Plasticity in Matrix Dominated Metal-Matrix Composite with One Active Slip Based Dislocation
Authors: Temesgen Takele Kasa
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The main aim of this paper is to suggest one active slip based continuum dislocation approach to matrix dominated MMC plasticity analysis. The approach centered the free energy principles through the continuum behavior of dislocations combined with small strain continuum kinematics. The analytical derivation of this method includes the formulation of one active slip system, the thermodynamic approach of dislocations, determination of free energy, and evolution of dislocations. In addition zero and non-zero energy dissipation analysis of dislocation evolution is also formulated by using varational energy minimization method. In general, this work shows its capability to analyze the plasticity of matrix dominated MMC with inclusions. The proposed method is also found to be capable of handling plasticity of MMC.Keywords: active slip, continuum dislocation, distortion, dominated, energy dissipation, matrix dominated, plasticity
Procedia PDF Downloads 3824496 Effect of Serine/Threonine Kinases on Autophagy Mechanism
Authors: Ozlem Oral, Seval Kilic, Ozlem Yedier, Serap Dokmeci, Devrim Gozuacik
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Autophagy is a degradation pathway, activating under stress conditions. It digests macromolecules, such as abnormal proteins and long-lived organelles by engulfing them and by subsequent delivery of the cargo to lysosomes. The members of the phospholipid-dependent serine/threonine kinases, involved in many signaling pathways, which are necessary for the regulation of cellular metabolic activation. Previous studies implicate that, serine/threonine kinases have crucial roles in the mechanism of many diseases depend on the activated and/or inactivated signaling pathway. Data indicates, the signaling pathways activated by serine/threonine kinases are also involved in activation of autophagy mechanism. However, the information about the effect of serine/threonine kinases on autophagy mechanism and the roles of these effects in disease formation is limited. In this study, we investigated the effect of activated serine/threonine kinases on autophagic pathway. We performed a commonly used autophagy technique, GFP-LC3 dot formation and by using microscopy analyses, we evaluated promotion and/or inhibition of autophagy in serine/threonine kinase-overexpressed fibroblasts as well as cancer cells. In addition, we carried out confocal microscopy analyses and examined autophagic flux by utilizing the differential pH sensitivities of RFP and GFP in mRFP-GFP-LC3 probe. Based on the shRNA-library based screening, we identified autophagy-related proteins affected by serine/threonine kinases. We further studied the involvement of serine/threonine kinases on the molecular mechanism of newly identified autophagy proteins and found that, autophagic pathway is indirectly controlled by serine/threonine kinases via specific autophagic proteins. Our data indicate the molecular connection between two critical cellular mechanisms, which have important roles in the formation of many disease pathologies, particularly cancer. This project is supported by TUBITAK-1001-Scientific and Technological Research Projects Funding Program, Project No: 114Z836.Keywords: autophagy, GFP-LC3 dot formation assay, serine/threonine kinases, shRNA-library screening
Procedia PDF Downloads 2874495 Analysis of the Evolution of Social and Economic Indicators of the Mercosur´s Members: 1980-2012
Authors: L. Aparecida Bastos, J. Leige Lopes, J. Crepaldi, R. Monteiro da Silva
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The objective of this study is to analyze the evolution of some social and economic indicators of Mercosur´s economies from 1980 to 2012, based on the statistics of the Latin American Integration Association (LAIA). The objective is to observe if after the accession of these economies to Mercosur (the first accessions occurred in 1994) these indicators showed better performance, in order to demonstrate if economic integration contributed to improved trade, macroeconomic performance, and level of social and economic development of member countries. To this end, the methodologies used will be a literature review and descriptive statistics. The theoretical framework that guides the work are the theories of Integration: Classical Liberal, Marxist and structural-proactive. The results reveal that most social and economic indicators showed better performance in those economies that joined Mercosur after 1994. This work is the result of an investigation already completed.Keywords: economic integration, Mercosur, social indicators, economic indicators
Procedia PDF Downloads 2914494 The Research on Decentralization Supervision Mechanism of Town and Village Culture Based On Authenticity Evaluation
Authors: Chao Ma
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In this paper, the evaluation criteria of authenticity evaluation system model are taken as the foundation so as to discuss the establishment problems about decentralization supervision system and mechanism of historical cultural town and village. The filtration of fitting towns and village's authenticity is conducted from the level, characteristic index and authentic assessment of evaluation model, thereby, supervising subject -interest related- coordinate organization can be taken as the venation in the management level, thus supervision mechanism of town and village's cultural inheritance can be combed, and the cultural inheritance management system and mechanism which is suitable to historical and cultural Chinese town and village will be provided. As the settlement with strong self-organizing characteristic, town and village don't recognize the management system as deeply as city. Therefore, it is necessary to establish town and village cultural evaluation system based on authenticity evaluation criteria. In this paper, authenticity evaluation system is established by taking this village's value evaluation criteria and protection as the cores, and the classification of participating options is beneficial to distribute local limited resources, protect hierarchically and accord with the local characters of town and village, build the evaluation system to run through the whole process of cultural inheritance, moreover, provide abundant information resources and make sure the value judgment criteria, thus supervision and management can be strengthened to effectively guard risk. By the above judgement and filtration of participating options, the management object with clear functions and supervision and coordination organization are established, thereby, the managerial logic of interest-related persons' decentralization can be clarified, evaluation system can be established, and the more targeted decentralization supervision system and mechanism of historical and cultural village will be built ultimately. Taking this method as a fundamental in cultural protection of town and village, not only can it be carried forward in the mass media, but also can cultivate the identity sense of indigenous people to come back historical and cultural villages, and resist the replacement of city culture.Keywords: authenticity, rural culture, inheritance, supervision
Procedia PDF Downloads 3334493 ‘Saying’ the Nuclear Power in France: Evolution of the Images and Perceptions of a Sensitive Theme
Authors: Jandot Aurélia
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As the nuclear power is a sensitive field leading to controversy, the quality of the communication about it is important. Between 1965 and 1981, in France, this one had gradually changed. This change is studied here in the main French news magazine L’Express, in connection with several parameters. As this represents a huge number of copies and occurrences, thus a considerable amount of information; this paper is focused on the main articles as well as the main “mental images”. These ones are important, as their aim is to direct the thought of the readers, and as they have led the public awareness to evolve. Over this 17 years, two trends are in confrontation: The first one is promoting the perception of the nuclear power, while the second one is discrediting it. These trends are organized in two axes: the evolution of engineering, and the risks. In both cases, the changes in the language allow discerning the deepest intentions of the magazine editing, over a period when the nuclear technology, to there a laboratory object accompanied with mystery and secret, has become a social issue seemingly open to all.Keywords: French news magazine, mental images, nuclear power, public awareness
Procedia PDF Downloads 3014492 Kinetics and Mechanism of Oxidation of Some Amino Acids by Peroxodisulphate
Authors: Abdelmahmod Saad
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In this study two amino acids were chosen (DL.alanine,DL.serine) to determine their effect on dissociation of S2O8-2 ino. As the reaction was very slow, Ag+ ino was used as a catalyst. The kinetics measurement showed that the reactions in both cases were found in the first order with respect to S2O8-2, half order with respect to Ag+ and zero order with respect to substrates. Mechanisms were proposed for these reactions according to the determined orders. The energy of activation (AE) was determined for each reaction, and was found to by 30.50 k JmoI-1 in case of DL. Serine and 24.40 k JmoI-1 in case of DL.alanine.Keywords: mechanism, oxidation, amino acids, peroxodisulphate
Procedia PDF Downloads 5054491 Proteome-Wide Convergent Evolution on Vocal Learning Birds Reveals Insight into cAMP-Based Learning Pathway
Authors: Chul Lee, Seoae Cho, Erich D. Jarvis, Heebal Kim
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Vocal learning, the ability to imitate vocalizations based on auditory experience, is a homoplastic character state observed in different independent lineages of animals such as songbirds, parrots, hummingbirds and human. It has now become possible to perform genome-wide molecular analyses across vocal learners and vocal non-learners with the recent expansion of avian genome data. It was analyzed the whole genomes of human and 48 avian species including those belonging to the three avian vocal learning lineages, to determine if behavior and neural convergence are associated with molecular convergence in divergent species of vocal learners. Analyses of 8295 orthologous genes across bird species revealed 141 genes with amino acid substitutions specific to vocal learners. Out of these, 25 genes have vocal learner specific genetic homoplasies, and their functions were enriched for learning. Several sites in these genes are estimated under convergent evolution and positive selection. A potential role for a subset of these genes in vocal learning was supported by associations with gene expression profiles in vocal learning brain regions of songbirds and human disease that cause language dysfunctions. The key candidate gene with multiple independent lines of the evidences specific to vocal learners was DRD5. Our findings suggest cAMP-based learning pathway in avian vocal learners, indicating molecular homoplastic changes associated with a complex behavioral trait, vocal learning.Keywords: amino acid substitutions, convergent evolution, positive selection, vocal learning
Procedia PDF Downloads 3344490 Approximate Spring Balancing for Swimming Pool Lift Mechanism to Reduce Actuator Torque
Authors: Apurva Patil, Sujatha Srinivasan
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Reducing actuator loads is important for applications in which human effort is required for actuation. The potential benefit of applying spring balancing to rehabilitation devices which work against gravity on a nonhorizontal plane is well recognized, but practical applications have been elusive. Although existing methods provide exact spring balance, they require additional masses or auxiliary links, or all the springs used originate from the ground, which makes the resulting device bulky and space-inefficient. This paper uses a method of static balancing of mechanisms with conservative loads such as gravity and spring loads using non-zero-free-length springs and no auxiliary links. Application of this method to a manually operated swimming pool lift mechanism which lowers and raises the physically challenged users into or out of the swimming pool is presented here. Various possible configurations using extension and compression springs as well as gas spring in the mechanism are compared. This work involves approximate spring balancing of the mechanism using minimization of potential energy variance. It uses the approach of flattening the potential energy distribution over the workspace and fuses it with numerical optimization. The results show the considerable reduction in actuator torque requirement with practical spring design and arrangement. Although the method provides only an approximate balancing, it is versatile, flexible in choosing appropriate control variables that are relevant to the design problem and easy to implement. The true potential of this technique lies in the fact that it uses a very simple optimization to find the spring constant, free length of the spring and the optimal attachment points subject to the optimization constraints. Also, it uses physically realizable non-zero-free-length springs directly, thereby reducing the complexity involved in simulating zero-free-length springs from non-zero-free-length springs. This method allows springs to be attached inside the mechanism, which makes the implementation of spring balancing practical. Because auxiliary linkages can be avoided, the resultant swimming pool lift mechanism is compact. The cost benefits and reduced complexity can be significant advantages in the development of this user-actuated swimming pool lift for developing countries.Keywords: gas spring, rehabilitation device, spring balancing, swimming pool lift
Procedia PDF Downloads 2384489 Design of a Satellite Solar Panel Deployment Mechanism Using the Brushed DC Motor as Rotational Speed Damper
Authors: Hossein Ramezani Ali-Akbari
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This paper presents an innovative method to control the rotational speed of a satellite solar panel during its deployment phase. A brushed DC motor has been utilized in the passive spring driven deployment mechanism to reduce the deployment speed. In order to use the DC motor as a damper, its connector terminals have been connected with an external resistance in a closed circuit. It means that, in this approach, there is no external power supply in the circuit. The working principle of this method is based on the back electromotive force (or back EMF) of the DC motor when an external torque (here the torque produced by the torsional springs) is coupled to the DC motor’s shaft. In fact, the DC motor converts to an electric generator and the current flows into the circuit and then produces the back EMF. Based on Lenz’s law, the generated current produced a torque which acts opposite to the applied external torque, and as a result, the deployment speed of the solar panel decreases. The main advantage of this method is to set an intended damping coefficient to the system via changing the external resistance. To produce the sufficient current, a gearbox has been assembled to the DC motor which magnifies the number of turns experienced by the DC motor. The coupled electro-mechanical equations of the system have been derived and solved, then, the obtained results have been presented. A full-scale prototype of the deployment mechanism has been built and tested. The potential application of brushed DC motors as a rotational speed damper has been successfully demonstrated.Keywords: back electromotive force, brushed DC motor, rotational speed damper, satellite solar panel deployment mechanism
Procedia PDF Downloads 3194488 A Tool for Rational Assessment of Dynamic Trust in Networked Organizations
Authors: Simon Samwel Msanjila
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Networked environments which provides platforms and environments for business organizations are configured in different forms depending on many factors including life time, member characteristics, communication structure, and business objectives, among others. With continuing advances in digital technologies the distance has become a less barrier for business minded collaboration among organizations. With the need and ease to make business collaborate nowadays organizations are sometimes forced to co-work with others that are either unknown or less known to them in terms of history and performance. A promising approach for sustaining established collaboration has been establishment of trust relationship among organizations based on assessed trustworthiness for each participating organization. It has been stated in research that trust in organization is dynamic and thus assessment of trust level must address such dynamic nature. This paper assess relevant aspects of trust and applies the concepts to propose a semi-automated system for assessing the Sustainability and Evolution of trust in organizations participating in specific objective in a networked organizations environment.Keywords: trust evolution, trust sustainability, networked organizations, dynamic trust
Procedia PDF Downloads 4234487 Proposing an Architecture for Drug Response Prediction by Integrating Multiomics Data and Utilizing Graph Transformers
Authors: Nishank Raisinghani
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Efficiently predicting drug response remains a challenge in the realm of drug discovery. To address this issue, we propose four model architectures that combine graphical representation with varying positions of multiheaded self-attention mechanisms. By leveraging two types of multi-omics data, transcriptomics and genomics, we create a comprehensive representation of target cells and enable drug response prediction in precision medicine. A majority of our architectures utilize multiple transformer models, one with a graph attention mechanism and the other with a multiheaded self-attention mechanism, to generate latent representations of both drug and omics data, respectively. Our model architectures apply an attention mechanism to both drug and multiomics data, with the goal of procuring more comprehensive latent representations. The latent representations are then concatenated and input into a fully connected network to predict the IC-50 score, a measure of cell drug response. We experiment with all four of these architectures and extract results from all of them. Our study greatly contributes to the future of drug discovery and precision medicine by looking to optimize the time and accuracy of drug response prediction.Keywords: drug discovery, transformers, graph neural networks, multiomics
Procedia PDF Downloads 1424486 Mechanism of Performance of Soil-Cement Columns under Shallow Foundations in Liquefiable Soil
Authors: Zaheer Ahmed Almani, Agha Faisal Habib Pathan, Aneel Kumar Hindu
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In this study, the effects of ground reinforcement with stiff soil-cement columns on liquefiable ground and on the shallow foundation of structure were investigated. The modelling and analysis of shallow foundation of the structure founded on the composite reinforced ground were carried out with finite difference FLAC commercial software. The results showed that stiff columns were not effective to the redistribute the shear stresses in the composite ground, thus, were not effective to reduce shear stress and shear strain on the soil between the columns. The excessive pore pressure increase which is dependent on volumetric strain (contractive) tendency of loose sand upon shearing, was not reduced to a significant level that liquefaction potential could be remediated. Thus, mechanism of performance with reduction of pore pressure and consequent liquefaction was not predicted in numerical analysis. Nonetheless, the columns were effective to resist the load of structure in compression and reduced the liquefaction-induced large settlements of structure to tolerable limits when provided adjacent and beneath the pad of shallow foundation.Keywords: earthquake, liquefaction, mechanism, soil-cement columns
Procedia PDF Downloads 1484485 An Analysis of Privacy and Security for Internet of Things Applications
Authors: Dhananjay Singh, M. Abdullah-Al-Wadud
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The Internet of Things is a concept of a large scale ecosystem of wireless actuators. The actuators are defined as things in the IoT, those which contribute or produces some data to the ecosystem. However, ubiquitous data collection, data security, privacy preserving, large volume data processing, and intelligent analytics are some of the key challenges into the IoT technologies. In order to solve the security requirements, challenges and threats in the IoT, we have discussed a message authentication mechanism for IoT applications. Finally, we have discussed data encryption mechanism for messages authentication before propagating into IoT networks.Keywords: Internet of Things (IoT), message authentication, privacy, security
Procedia PDF Downloads 3774484 A Comparison of the Adsorption Mechanism of Arsenic on Iron-Modified Nanoclays
Authors: Michael Leo L. Dela Cruz, Khryslyn G. Arano, Eden May B. Dela Pena, Leslie Joy Diaz
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Arsenic adsorbents were continuously being researched to ease the detrimental impact of arsenic to human health. A comparative study on the adsorption mechanism of arsenic on iron modified nanoclays was undertaken. Iron intercalated montmorillonite (Fe-MMT) and montmorillonite supported zero-valent iron (ZVI-MMT) were the adsorbents investigated in this study. Fe-MMT was produced through ion-exchange by replacing the sodium intercalated ions in montmorillonite with iron (III) ions. The iron (III) in Fe-MMT was later reduced to zero valent iron producing ZVI-MMT. Adsorption study was performed by batch technique. Obtained data were fitted to intra-particle diffusion, pseudo-first order, and pseudo-second-order models and the Elovich equation to determine the kinetics of adsorption. The adsorption of arsenic on Fe-MMT followed the intra-particle diffusion model with intra-particle rate constant of 0.27 mg/g-min0.5. Arsenic was found to be chemically bound on ZVI-MMT as suggested by the pseudo-second order and Elovich equation. The derived pseudo-second order rate constant was 0.0027 g/mg-min with initial adsorption rate computed from the Elovich equation was 113 mg/g-min.Keywords: adsorption mechanism, arsenic, montmorillonite, zero valent iron
Procedia PDF Downloads 4074483 Analyzing and Predicting the CL-20 Detonation Reaction Mechanism Based on Artificial Intelligence Algorithm
Authors: Kaining Zhang, Lang Chen, Danyang Liu, Jianying Lu, Kun Yang, Junying Wu
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In order to solve the problem of a large amount of simulation and limited simulation scale in the first-principle molecular dynamics simulation of energetic material detonation reaction, we established an artificial intelligence model for analyzing and predicting the detonation reaction mechanism of CL-20 based on the first-principle molecular dynamics simulation of the multiscale shock technique (MSST). We employed principal component analysis to identify the dominant charge features governing molecular reactions. We adopted the K-means clustering algorithm to cluster the reaction paths and screen out the key reactions. We introduced the neural network algorithm to construct the mapping relationship between the charge characteristics of the molecular structure and the key reaction characteristics so as to establish a calculation method for predicting detonation reactions based on the charge characteristics of CL-20 and realize the rapid analysis of the reaction mechanism of energetic materials.Keywords: energetic material detonation reaction, first-principle molecular dynamics simulation of multiscale shock technique, neural network, CL-20
Procedia PDF Downloads 101