Search results for: Collapse mechanisms.
294 Performance Analysis of Wireless Ad-Hoc Network Based on EDCA IEEE802.11e
Authors: Shah Ahsanuzzaman Md. Tariq, Fabrizio Granelli
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IEEE 802.11e is the enhanced version of the IEEE 802.11 MAC dedicated to provide Quality of Service of wireless network. It supports QoS by the service differentiation and prioritization mechanism. Data traffic receives different priority based on QoS requirements. Fundamentally, applications are divided into four Access Categories (AC). Each AC has its own buffer queue and behaves as an independent backoff entity. Every frame with a specific priority of data traffic is assigned to one of these access categories. IEEE 802.11e EDCA (Enhanced Distributed Channel Access) is designed to enhance the IEEE 802.11 DCF (Distributed Coordination Function) mechanisms by providing a distributed access method that can support service differentiation among different classes of traffic. Performance of IEEE 802.11e MAC layer with different ACs is evaluated to understand the actual benefits deriving from the MAC enhancements.Keywords: 802.11e, fairness, enhanced distributed channelaccess, access categories, quality of Service.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1945293 Attention Multiple Instance Learning for Cancer Tissue Classification in Digital Histopathology Images
Authors: Afaf Alharbi, Qianni Zhang
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The identification of malignant tissue in histopathological slides holds significant importance in both clinical settings and pathology research. This paper presents a methodology aimed at automatically categorizing cancerous tissue through the utilization of a multiple instance learning framework. This framework is specifically developed to acquire knowledge of the Bernoulli distribution of the bag label probability by employing neural networks. Furthermore, we put forward a neural network-based permutation-invariant aggregation operator, equivalent to attention mechanisms, which is applied to the multi-instance learning network. Through empirical evaluation on an openly available colon cancer histopathology dataset, we provide evidence that our approach surpasses various conventional deep learning methods.
Keywords: Attention Multiple Instance Learning, Multiple Instance Learning, transfer learning, histopathological slides, cancer tissue classification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 221292 Terrorism: A Threat in Constant Evolution Still Misunderstood
Authors: Manuel J. Gazapo Lapayese
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It is a well-established fact that terrorism is one of the foremost threats to present-day international security. The creation of tools or mechanisms for confronting it in an effective and efficient manner will only be possible by way of an objective assessment of the phenomenon. In order to achieve this, this paper has the following three main objectives: Firstly, setting out to find the reasons that have prevented the establishment of a universally accepted definition of terrorism, and consequently trying to outline the main features defining the face of the terrorist threat in order to discover the fundamental goals of what is now a serious blight on world society. Secondly, trying to explain the differences between a terrorist movement and a terrorist organisation, and the reasons for which a terrorist movement can be led to transform itself into an organisation. After analysing these motivations and the characteristics of a terrorist organisation, an example of the latter will be succinctly analysed to help the reader understand the ideas expressed. Lastly, discovering and exposing the factors that can lead to the appearance of terrorist tendencies, and discussing the most efficient and effective responses that can be given to this global security threat.
Keywords: Responses, resilience, security, terrorism.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2580291 Influence of Natural Gum on Curcumin Supersaturation in Gastrointestinal Fluids
Authors: Patcharawalai Jaisamut, Kamonthip Wiwattanawongsa, Ruedeekorn Wiwattanapatapee
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Supersaturation of drugs in the gastrointestinal tract is one approach to increase the absorption of poorly water-soluble drugs. The stabilization of a supersaturated state was achieved by adding precipitation inhibitors that may act through a variety of mechanisms. In this study, the effect of the natural gums, acacia, gelatin, pectin and tragacanth on curcumin supersaturation in simulated gastric fluid (SGF) (pH 1.2), fasted state simulated gastric fluid (FaSSGF) (pH 1.6), and simulated intestinal fluid (SIF) (pH 6.8) was investigated. The results indicated that all natural gums significantly increased the curcumin solubility (about 1.2-6-fold) when compared to the absence of gum, and assisted in maintaining the supersaturated drug solution. Among the tested gums, pectin at 3% w/w was the best precipitation inhibitor with a significant increase in the degree of supersaturation about 3-fold in SGF, 2.4-fold in FaSSGF and 2-fold in SIF.
Keywords: Curcumin, Solubility, Supersaturation, Precipitation inhibitor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2318290 Formation of Protective Silicide-Aluminide Coating on Gamma-TiAl Advanced Material
Authors: S. Nouri
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In this study, the Si-aluminide coating was prepared on gamma-TiAl [Ti-45Al-2Nb-2Mn-1B (at. %)] via liquid-phase slurry procedure. The high temperature oxidation resistance of this diffusion coating was evaluated at 1100 °C for 400 hours. The results of the isothermal oxidation showed that the formation of Si-aluminide coating can remarkably improve the high temperature oxidation of bare gamma-TiAl alloy. The identification of oxide scale microstructure showed that the formation of protective Al2O3+SiO2 mixed oxide scale along with a continuous, compact and uniform layer of Ti5Si3 beneath the surface oxide scale can act as an oxygen diffusion barrier during the high temperature oxidation. The other possible mechanisms related to the formation of Si-aluminide coating and oxide scales were also discussed.
Keywords: Gamma-TiAl alloy, Si-aluminide coating, slurry procedure, high temperature oxidation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 671289 Simulation and Experimentation of Multibody Mechanical Systems with Clearance Revolute Joints
Authors: A.F. Haroun, S.M. Megahed
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Clearance in the joints of multibody mechanical systems such as linkage mechanisms and robots is a main source of vibration, and noise of the whole system, and wear of the joints themselves. This clearance is an inevitable matter and cannot be eliminated, since it allows the relative motion between joint components and make them assemblage. This paper presents an experimental verification of the obtained simulation results of a slider – crank mechanism of one clearance revolute joint. The simulation results are obtained with the aid of CAD and dynamic simulation softwares, which is an effective method of simulation multibody systems with clearance joints and have many advantages. The comparison between both simulation and experimental results shows that the simulation results are so close to the experimental ones which proves the accuracy and efficiency of this method of modeling and simulation of mechanical systems with clearance joints.Keywords: CAD and dynamic simulator softwares, Clearance joints, , Experimental results, Slider – crank mechanism.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2702288 A Formal Approach for Instructional Design Integrated with Data Visualization for Learning Analytics
Authors: Douglas A. Menezes, Isabel D. Nunes, Ulrich Schiel
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Most Virtual Learning Environments do not provide support mechanisms for the integrated planning, construction and follow-up of Instructional Design supported by Learning Analytic results. The present work aims to present an authoring tool that will be responsible for constructing the structure of an Instructional Design (ID), without the data being altered during the execution of the course. The visual interface aims to present the critical situations present in this ID, serving as a support tool for the course follow-up and possible improvements, which can be made during its execution or in the planning of a new edition of this course. The model for the ID is based on High-Level Petri Nets and the visualization forms are determined by the specific kind of the data generated by an e-course, a population of students generating sequentially dependent data.
Keywords: Educational data visualization, high-level petri nets, instructional design, learning analytics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 848287 Free Convection in a MHD Porous Cavity with using Lattice Boltzmann Method
Authors: H.A. Ashorynejad, M. Farhadi, K.Sedighi, A.Hasanpour
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We report the results of an lattice Boltzmann simulation of magnetohydrodynamic damping of sidewall convection in a rectangular enclosure filled with a porous medium. In particular we investigate the suppression of convection when a steady magnetic field is applied in the vertical direction. The left and right vertical walls of the cavity are kept at constant but different temperatures while both the top and bottom horizontal walls are insulated. The effects of the controlling parameters involved in the heat transfer and hydrodynamic characteristics are studied in detail. The heat and mass transfer mechanisms and the flow characteristics inside the enclosure depended strongly on the strength of the magnetic field and Darcy number. The average Nusselt number decreases with rising values of the Hartmann number while this increases with increasing values of the Darcy number.Keywords: Lattice Boltzmann method , Natural convection , Magnetohydrodynamic , Porous medium
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2008286 Interspecific Variation in Heat Stress Tolerance and Oxidative Damage among 15 C3 Species
Authors: Wagdi S. Soliman, Shu-ichi Sugiyama
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The C3 plants are frequently suffering from exposure to high temperature stress which limits the growth and yield of these plants. This study seeks to clarify the physiological mechanisms of heat tolerance in relation to oxidative stress in C3 species. Fifteen C3 species were exposed to prolonged moderately high temperature stress 36/30°C for 40 days in a growth chamber. Chlorophyll fluorescence (Fv/Fm) showed great difference among species at 40 days of the stress. The species showed decreases in Fv/Fm and increases in malondialdehyde (MDA) content under stress condition as well as negative correlation between Fv/Fm and MDA (r = -0.61*) at 40 days of the stress. Hydrogen peroxide (H2O2) content before and after stress in addition to its response under stress showed great differences among species. The results suggest that the difference in heat tolerance among C3 species is closely associated with the ability to suppress oxidative damage but not with the content of reactive oxygen species (ROS) which is regulated by complex network.Keywords: C3 species, Fv/Fm, heat stress, oxidative stress.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1756285 Smart Motion
Authors: Arpita Soni, Sapna Mittal
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Austenite and Martensite indicate the phases of solids undergoing phase transformation which we usually associate with materials and not with living organisms. This article provides an overview of bacterial proteins and structures that are undergoing phase transformation and suggests its probable effect on mechanical behavior. The context is mainly within the role of phase transformations occurring in the flagellum of bacteria. The current knowledge of molecular mechanism leading to phase variation in living organisms is reviewed. Since in bacteria, each flagellum is driven by a separate motor, similarity to a Differential drive in case of four-wheeled vehicles is suggested. It also suggests the application of the mechanism in which bacteria changes its direction of movement to facilitate single point turning of a multi-wheeled vehicle. Finally, examples are presented to illustrate that the motion due to phase transformation of flagella in bacteria can start a whole new research on motion mechanisms.
Keywords: Flagella, Phase Transformation, Nanobots, Differential Drive, Single point turn, Biomimetics
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1570284 Solid Particle Erosion of Heat Treated TNB-V4 at Ambient and Elevated Temperatures
Authors: Muhammad Naveed, Richard Stechow, Sebastian Bolz, Katharina Hobusch, Sabine Weiß
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Solid particle erosion has been identified as a critical wear phenomenon which takes place during operation of aeroengines in dusty environment. The present work discusses the erosion behavior of Ti-44.5Al-6.25Nb-0.8Mo-0.1B alloy (TNB-V4) which finds its application in low pressure gas turbines and can be used for high pressure compressors too. Prior to the erosion tests, the alloy was heat treated to improve the mechanical properties. Afterwards, specimens were eroded at impact angles of 30° and 90° at room and high temperatures (100 °C-400 °C). Volume loss and erosion behavior are studied through gravimetric analysis, whereas erosion mechanisms are characterized through scanning electron microscopy. The results indicate a clear difference in the erosion mechanism for different impact angles. The influence of the test temperature on the erosion behavior of the alloy is also discussed in the present contribution.
Keywords: Solid particle erosion, gamma TiAl, TNB-V4, high temperature erosion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1517283 Negative Emotions and Ways of Overcoming them in Prison
Authors: Katarzyna Czubak
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The aim of this paper is description of the notion of the death for prisoners and the ways of deal with. They express indifference, coldness, inability to accept the blame, they have no shame and no empathy. Is it enough to perform acts verging on the death. In this paper we described mechanisms and regularities of selfdestructive behaviour in the view of the relevant literature? The explanation of the phenomenon is of a biological and sociopsychological nature. It must be clearly stated that all forms of selfdestructive behaviour result from various impulses, conflicts and deficits. That is why they should be treated differently in terms of motivation and functions which they perform in a given group of people. Behind self-destruction there seems to be a motivational mechanism which forces prisoners to rebel and fight against the hated law and penitentiary systems. The imprisoned believe that pain and suffering inflicted on them by themselves are better than passive acceptance of repression. The variety of self-destruction acts is wide, and some of them take strange forms. We assume that a life-death barrier is a kind of game for them. If they cannot change the degrading situation, their life loses sense.Keywords: Self- destruction, Simulation, Negative emotions, Consequences of conviction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1487282 Investigating Breakdowns in Human Robot Interaction: A Conversation Analysis Guided Single Case Study of a Human-Robot Communication in a Museum Environment
Authors: B. Arend, P. Sunnen, P. Caire
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In a single case study, we show how a conversation analysis (CA) approach can shed light onto the sequential unfolding of human-robot interaction. Relying on video data, we are able to show that CA allows us to investigate the respective turn-taking systems of humans and a NAO robot in their dialogical dynamics, thus pointing out relevant differences. Our fine grained video analysis points out occurring breakdowns and their overcoming, when humans and a NAO-robot engage in a multimodally uttered multi-party communication during a sports guessing game. Our findings suggest that interdisciplinary work opens up the opportunity to gain new insights into the challenging issues of human robot communication in order to provide resources for developing mechanisms that enable complex human-robot interaction (HRI).
Keywords: Human-robot interaction, conversation analysis, dialogism, museum, breakdown.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1411281 A Study of DSRC Radio Testbed under Heavy Channel Load
Authors: Chih-Neng Liang, Bo-Chiuan Chen, C. W. Hsu
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Dedicated Short Range Communication (DSRC) is a key enabling technology for the next generation of communication-based safety applications. One of the important problems for DSRC deployment is maintaining high performance under heavy channel load. Many studies focus on congestion control mechanisms for simulating hundreds of physical radios deployed on vehicles. The U.S. department of transportation-s (DOT) Intelligent Transportation Systems (ITS) division has a plan to chosen prototype on-board devices capable of transmitting basic “Here I am" safety messages to other vehicles. The devices will be used in an IntelliDrive safety pilot deployment of up to 3,000 vehicles. It is hard to log the information of 3,000 vehicles. In this paper we present the designs and issues related to the DSRC Radio Testbed under heavy channel load. The details not only include the architecture of DSRC Radio Testbed, but also describe how the Radio Interfere System is used to help for emulating the congestion radio environment.Keywords: DSRC, UDP, WAVE, Radio Testbed
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1801280 The Strange Relationship between Literacy and Well-Being: The Results of an International Survey with Special Focus on Italy
Authors: Federica Cornali
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Does education matter to the quality of our life? The results of extensive studies offer an affirmative answer to this question: high education levels are positively associated with higher income, with more highly qualified professions, with lower risk of unemployment, with better physical health and also, it is said, with more happiness. However, exploring these relationships is far from straightforward. Aside from educational credentials, what properties distinguish functionally literate individuals? How can their personal level of satisfaction be measured? What are the social mechanisms whereby education affects well-being?Using a literacy index and several measures for well-being developed by secondary analysis of the Adult Literacy and Life Skills Survey database, this investigation examined the relationship between literacy skills and subjective wellbeing in several OECD (Organisation for Economic Co-operation and Development) countries. Special attention was been addressed to Italy, and in particular to two regions representing territorial differences in this country: Piedmont and Campania.
Keywords: Cultural Divide, Literacy Index, Life Satisfaction, Subjective Well-being Index
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3307279 Government Responses to the Survivors of Trafficking in Human Beings: A Study of Albania
Authors: Irida Agolli Nasufi, Anxhela Bruci
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This paper presents Albanian government policies regarding the reintegration process for returning Albanian survivors of trafficking in human beings. Focusing on an in-depth analysis of governmental, non-governmental documents and semi-structured qualitative interviews conducted with service providers and trafficking survivors. Furthermore, this paper will especially focus on the governmental efforts to provide support to the survivors, focusing on their needs and challenges. This study explores the conditions and actual services provided to the survivors of trafficking in human beings that are in the reintegration process in Albania. Moreover, it examines the responsible mechanisms accountable for the reintegration process, by analysing synergies between governmental and non-governmental organisations. Also, this paper explores the governmental approach towards trafficking survivors and apprises policymakers to undertake changes and reforms in their future actions.
Keywords: Policies, social services, service user, trafficking in human beings, government.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 761278 Graft Copolymerization of Methyl Methacrylate onto Cellulose in Homogeneous Medium – Effect of Solvent and Initiator
Authors: B. Tosh, C. R. Routray
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Homogeneous graft copolymerization of methyl methacrylate (MMA) onto cellulose was carried out in N, N – dimethyl acetamide/LiCl (DMAc/LiCl) and dimethyl sulfoxide/ paraformaldehyde (DMSO/PF) solvent system taking ceric ammonium nitrate (CAN), benzoyl peroxide (BPO) and tin (II)-2-ethyl hexanoate [Sn(Oct)2] as initiators. Different grafting parameters like graft yield (GY), grafting efficiency (GE) and total conversion of monomer to polymer (TC) were evaluated at different reaction conditions of temperature, time, and variation of the amount of monomer and initiator. The viscosity average molecular weight of grafted PMMA and number of grafts per cellulose chain were also calculated. The products were characterized by FT-IR and 1H-NMR analyses and possible reaction mechanisms were deduced. Thermal degradation of the grafted products was also studied by thermo-gravimetric analysis (TG) and differential thermo-gravimetry (DTG).
Keywords: Grafting, grafting efficiency, homogeneous medium, methyl methacrylate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3184277 Deposit Guarantee Fund: One Perspective
Authors: Rute Abreu, Fátima David, Liliane Cristina Segura
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The Deposit Guarantee Fund (DGF) and its communication with the Society, in general, and with the deposit client of Financial Institutions, in particular, is discussed through the challenges of the accounting and financial report. The Bank of Portugal promotes the Portuguese Deposit Guarantee Fund (PDGF) as a financial institution that enhanced the market confidence and stability on the deposit-insurance system. Due to the nature of their functions, it must be subject to regulation and supervision that provides a first line of defense against adversely affect confidence on the Portuguese financial market. First, this research provides evidence of the effectiveness of the protection mechanisms on the deposit insurance system, which provides high and equal protection to all stakeholders. Second, it emphasizes the need of requirements of rigorous accounting process and effective financial report to reduce the moral hazard implications. Third, this research focuses on the need of total disclosure of the financial information which gives higher transparency and protection to deposit client of financial institutions.
Keywords: Deposit Guarantee Fund, Portugal, Accounting, Financial Report.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1555276 A Timed and Colored Petri Nets for Modeling and Verifying Cloud System Elasticity
Authors: W. Louhichi, M.Berrima, N. Ben Rajeb Robbana
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Elasticity is the essential property of cloud computing. As the name suggests, it constitutes the ability of a cloud system to adjust resource provisioning in relation to fluctuating workloads. There are two types of elasticity operations, vertical and horizontal. In this work, we are interested in horizontal scaling, which is ensured by two mechanisms; scaling in and scaling out. Following the sizing of the system, we can adopt scaling in the event of over-supply and scaling out in the event of under-supply. In this paper, we propose a formal model, based on temporized and colored Petri nets (TdCPNs), for the modeling of the duplication and the removal of a virtual machine from a server. This model is based on formal Petri Nets (PNs) modeling language. The proposed models are edited, verified, and simulated with two examples implemented in colored Petri nets (CPNs)tools, which is a modeling tool for colored and timed PNs.
Keywords: Cloud computing, elasticity, elasticity controller, petri nets, scaling in, scaling out.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 646275 Bandwidth Optimization through Dynamic Routing in ATM Networks: Genetic Algorithm and Tabu Search Approach
Authors: Susmi Routray, A. M. Sherry, B. V. R. Reddy
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Asynchronous Transfer Mode (ATM) is widely used in telecommunications systems to send data, video and voice at a very high speed. In ATM network optimizing the bandwidth through dynamic routing is an important consideration. Previous research work shows that traditional optimization heuristics result in suboptimal solution. In this paper we have explored non-traditional optimization technique. We propose comparison of two such algorithms - Genetic Algorithm (GA) and Tabu search (TS), based on non-traditional Optimization approach, for solving the dynamic routing problem in ATM networks which in return will optimize the bandwidth. The optimized bandwidth could mean that some attractive business applications would become feasible such as high speed LAN interconnection, teleconferencing etc. We have also performed a comparative study of the selection mechanisms in GA and listed the best selection mechanism and a new initialization technique which improves the efficiency of the GA.Keywords: Asynchronous Transfer Mode(ATM), GeneticAlgorithm(GA), Tabu Search(TS).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1769274 Possible Role of Polyamine on Tumor Spread after Surgical Trauma
Authors: Kuniyasu Soda
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Surgical trauma seems to facilitate metastatic spread, although the underlying mechanisms are not known. Increased concentrations of polyamines (spermine and spermidine) in the blood seem to have associated with the enhanced malignant potential of cancer cells and decrease in anti-tumor immunity of cancer patients. In addition to de novo synthesis in rapidly growing cells such as normal regenerating cells and cancer cells, cells can take up polyamines from extra-cellular sources. We have shown that increased polyamine concentration results in decreases in cytokine production and expression of adhesion molecules involved in anti-tumor immunity, such as CD11a. And, immune cells in an environment with increased polyamine levels lose anti-tumor immune functions, such as lymphokine activated killer cell (LAK) activities. Because blood polyamine levels are increased in post-surgical patients, polyamine seems to have roles on post-traumatic tumor spread.
Keywords: Immune function, LAK, Polyamine, Surgical trauma.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1762273 Evaluating the Durability and Safety of Lithium-Ion Batteries in High-Temperature Desert Climates
Authors: Kenza Maher, Yahya Zakaria, Noora S. Al-Jaidah
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Temperature is a critical parameter for lithium-ion battery performance, life, and safety. In this study, four commercially available 18650 lithium-ion cells from four different manufacturers are subjected to accelerated cycle aging for up to 500 cycles at two different temperatures (25 °C and 45 °C). The cells are also calendar-aged at the same temperatures in both charged and discharged states for six months to investigate the effect of aging and temperature on capacity fade and state of health. The results showed that all battery cells demonstrated good cyclability and had a good state of health at both temperatures. However, the capacity loss and state of health of these cells are found to be dependent on the cell chemistry and aging conditions, including temperature. Specifically, the capacity loss is found to be higher at the higher aging temperature, indicating the significant impact of temperature on the aging of lithium-ion batteries.
Keywords: Lithium-ion battery, aging mechanisms, cycle aging, calendar aging.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 206272 Computational Study and Wear Prediction of Steam Turbine Blade with Titanium-Nitride Coating Deposited by Physical Vapor Deposition Method
Authors: Karuna Tuchinda, Sasithon Bland
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This work investigates the wear of a steam turbine blade coated with titanium nitride (TiN), and compares to the wear of uncoated blades. The coating is deposited on by physical vapor deposition (PVD) method. The working conditions of the blade were simulated and surface temperature and pressure values as well as flow velocity and flow direction were obtained. This data was used in the finite element wear model developed here in order to predict the wear of the blade. The wear mechanisms considered are erosive wear due to particle impingement and fluid jet, and fatigue wear due to repeated impingement of particles and fluid jet. Results show that the life of the TiN-coated blade is approximately 1.76 times longer than the life of the uncoated one.
Keywords: Physical vapour deposition, steam turbine blade, titanium-based coating, wear prediction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3153271 Multimode Dynamics of the Beijing Road Traffic System
Authors: Zundong Zhang, Limin Jia, Xiaoliang Sun
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The Beijing road traffic system, as a typical huge urban traffic system, provides a platform for analyzing the complex characteristics and the evolving mechanisms of urban traffic systems. Based on dynamic network theory, we construct the dynamic model of the Beijing road traffic system in which the dynamical properties are described completely. Furthermore, we come into the conclusion that urban traffic systems can be viewed as static networks, stochastic networks and complex networks at different system phases by analyzing the structural randomness. As well as, we demonstrate the evolving process of the Beijing road traffic network based on real traffic data, validate the stochastic characteristics and the scale-free property of the network at different phasesKeywords: Dynamic Network Models, Structural Randomness, Scale-free Property, Multi-mode character
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1531270 Modeling “Web of Trust“ with Web 2.0
Authors: Omer Mahmood, Selvakennedy Selvadurai
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“Web of Trust" is one of the recognized goals for Web 2.0. It aims to make it possible for the people to take responsibility for what they publish on the web, including organizations, businesses and individual users. These objectives, among others, drive most of the technologies and protocols recently standardized by the governing bodies. One of the great advantages of Web infrastructure is decentralization of publication. The primary motivation behind Web 2.0 is to assist the people to add contents for Collective Intelligence (CI) while providing mechanisms to link content with people for evaluations and accountability of information. Such structure of contents will interconnect users and contents so that users can use contents to find participants and vice versa. This paper proposes conceptual information storage and linking model, based on decentralized information structure, that links contents and people together. The model uses FOAF, Atom, RDF and RDFS and can be used as a blueprint to develop Web 2.0 applications for any e-domain. However, primary target for this paper is online trust evaluation domain. The proposed model targets to assist the individuals to establish “Web of Trust" in online trust domain.Keywords: Web of Trust, Semantic Web, Electronic SocialNetworks, Information Management
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2222269 Analysis and Prediction of the Behavior of the Landslide at Ain El Hammam, Algeria Based on the Second Order Work Criterion
Authors: Zerarka Hizia, Akchiche Mustapha, Prunier Florent
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The landslide of Ain El Hammam (AEH) is characterized by a complex geology and a high hydrogeology hazard. AEH's perpetual reactivation compels us to look closely at its triggers and to better understand the mechanisms of its evolution in mass and in depth. This study builds a numerical model to simulate the influencing factors such as precipitation, non-saturation, and pore pressure fluctuations, using Plaxis software. For a finer analysis of instabilities, we use Hill's criterion, based on the sign of the second order work, which is the most appropriate material stability criterion for non-associated elastoplastic materials. The results of this type of calculation allow us, in theory, to predict the shape and position of the slip surface(s) which are liable to ground movements of the slope, before reaching the rupture given by the plastic limit of Mohr Coulomb. To validate the numerical model, an analysis of inclinometer measures is performed to confirm the direction of movement and kinematic of the sliding mechanism of AEH’s slope.Keywords: Landslide, second order work, precipitation, inclinometers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1113268 Effective Software-Based Solution for Processing Mass Downstream Data in Interactive Push VOD System
Authors: Ni Hong, Wu Guobin, Wu Gang, Pan Liang
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Interactive push VOD system is a new kind of system that incorporates push technology and interactive technique. It can push movies to users at high speeds at off-peak hours for optimal network usage so as to save bandwidth. This paper presents effective software-based solution for processing mass downstream data at terminals of interactive push VOD system, where the service can download movie according to a viewer-s selection. The downstream data is divided into two catalogs: (1) the carousel data delivered according to DSM-CC protocol; (2) IP data delivered according to Euro-DOCSIS protocol. In order to accelerate download speed and reduce data loss rate at terminals, this software strategy introduces caching, multi-thread and resuming mechanisms. The experiments demonstrate advantages of the software-based solution.Keywords: DSM-CC, data carousel, Euro-DOCSIS, push VOD.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1489267 Evolved Disease Avoidance Mechanisms, Generalized Prejudice, Modern Attitudes towards Individuals with Intellectual Disability
Authors: Campbell Townsend, David Hamilton
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Previous research has demonstrated that negative attitudes towards people with physical disabilities and obesity are predicted by a component of perceived vulnerability to disease; germ aversion. These findings have been suggested as illustrations of an evolved but over-active mechanism which promotes the avoidance of pathogen-carrying individuals. To date, this interpretation of attitude formation has not been explored with regard to people with intellectual disability, and no attempts have been made to examine possible mediating factors. This study examined attitudes in 333 adults and demonstrated that the moderate positive relationship between germ aversion and negative attitudes toward people with intellectual disability is fully mediated by social dominance orientation, a general preference for hierarchies and inequalities among social groups. These findings have implications for the design of programs which attempt to promote community acceptance and inclusion of people with disabilities.Keywords: avoidance, evolutionary psychology, intellectual disability, prejudice
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1930266 CFD Flow and Heat Transfer Simulation for Empty and Packed Fixed Bed Reactor in Catalytic Cracking of Naphtha
Authors: D. Salari, A. Niaei, P. Chitsaz Yazdi, M. Derakhshani, S. R. Nabavi
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This work aims to test the application of computational fluid dynamics (CFD) modeling to fixed bed catalytic cracking reactors. Studies of CFD with a fixed bed design commonly use a regular packing with N=2 to define bed geometry. CFD allows us to obtain a more accurate view of the fluid flow and heat transfer mechanisms present in fixed bed equipment. Naphtha was used as feedstock and the reactor length was 80cm. It is divided in three sections that catalyst bed packed in the middle section of the reactor. The reaction scheme was involved one primary reaction and 24 secondary reactions. Because of high CPU times in these simulations, parallel processing have been used. In this study the coke formation process in fixed bed and empty tube reactor was simulated and coke in these reactors are compared. In addition, the effect of steam ratio and feed flow rate on coke formation was investigated.Keywords: Coke Formation, CFD Simulation, Fixed Bed, Catalyitic Cracking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2506265 Process Optimization for Enhanced Production of Cell Biomass and Metabolites of Fluorescent Pseudomonad R81
Authors: M.V.R.K Sarma, Krishna Saharan, Lalit Kumar, Ashwani Gautam, Avhijeet Kapoor, Nishant Srivastava, Vikram Sahai, V.S Bisaria
Abstract:
The fluorescent pseudomonad strain R81 is a root colonizing rhizobacteria which promotes the growth of many plants by various mechanisms. Its broth containing siderophore (ironchelating compound) and 2,4- diacetyl phloroglucinol (DAPG) is used for preparing bioinoculant formulations for agronomical applications. Glycerol was found to be the best carbon source for improved biomass production. Splitting of nitrogen source to NH4Cl and urea had a stabilizing effect on pH during batch cultivation. Ltryptophan at 0.5 % in the medium increased the siderophore production to 850 mg/l. During batch cultivation of the strain in a bioreactor, a maximum of 4 g/l of dry cell mass, 1.8 g/l of siderophore and 20 mg/l of DAPG was achieved when glycerol was 15 g/l and C/N ratio was maintained at 12.5. In case of intermittent feeding of fresh medium during fed-batch cultivation, the dry cell mass was increased to 25 g/l with improved production of DAPG to 70 mg/l.Keywords: Batch cultivation, Fed-batch cultivation, fluorescent pseudomonad, Metabolites
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