Search results for: vibrational dynamics

Authors: Clara Voyvodic

Abstract:

Transitions from conflict to peace are by no means smooth nor linear, particularly from the perspective of those living through them. Over the last few decades, the changing focus in peacebuilding studies has come to appreciate the everyday experience of communities and how that provides a lens through which the relative success or efficacy of these transitions can be understood. In particular, the demobilization of a significant conflict actor is not without consequences, not just for the macro-view of state stabilization and peace, but for the communities who find themselves without a clear authority of territorial control. In Colombia, the demobilization and disarmament of the FARC guerilla group provided a brief respite to the conflict and a major political win for President Manuel Santos. However, this victory has proven short-lived. Drawing from extensive field research in Colombia within the last year, including interviews with local communities and actors operating in these regions, field observations, and other primary resources, this paper examines the post-accord transitions in Colombia and the everyday security experiences of local communities in regions formerly controlled by the FARC. In order to do so, the research focused on a semi-ethnographic approach in the northern region of the department of Antioquia and the coastal area of the border department of Nariño that documented how individuals within these marginalized communities have come to understand and negotiate their security in the years following the accord and the demobilization of the FARC. This presentation will argue that the removal of the FARC as an informal governance actor opened a space for multiple actors to attempt to control the same territory, including the state. This shift has had a clear impact on the everyday security experiences of the local communities. With an exploration of the dynamics of local governance and its impact on lived security experiences, this research seeks to demonstrate how distinct patterns of armed group behavior are emerging not only from a vacuum of control left by the FARC but from an increase in state presence that nonetheless remains inconsistent and unpersuasive as a monopoly of force in the region. The increased multiplicity of actors, particularly the state, has meant that the normal (informal) rules for communities to navigate these territories are no longer in play as the identities, actions, and intentions of different competing groups have become frustratingly opaque. This research provides a prescient analysis on how the shifting dynamics of territorial control in a post-peace accord landscape produce uncertain realities that affect the daily lives of the local communities and endanger the long-term prospect of human-centered security.

Keywords: armed actors, conflict transitions, informal governance, post-accord, security experiences

Procedia PDF Downloads 131

Authors: A. Morsli, A. Tlemçani, N. Ould Cherchali, M. S. Boucherit

Abstract:

This article presents two methods for the compensation of harmonics generated by a nonlinear load. The first is the classic method P-Q. The second is the controller by modern method of artificial intelligence specifically fuzzy logic. Both methods are applied to an Active Power Filter shunt (APFs) based on a three-phase voltage converter at five levels NPC topology. In calculating the harmonic currents of reference, we use the algorithm P-Q and pulse generation, we use the intersective PWM. For flexibility and dynamics, we use fuzzy logic. The results give us clear that the rate of Harmonic Distortion issued by fuzzy logic is better than P-Q.

Keywords: fuzzy logic controller, P-Q method, pulse width modulation (PWM), shunt active power filter (sAPF), total harmonic distortion (THD)

Procedia PDF Downloads 547

Authors: M. H. Alhajeri, Hamad M. Alhajeri, A. H. Alenezi

Abstract:

This paper reports a Computational Fluid Dynamics (CFD) investigation for a high-temperature high-pressure filtration (ceramic candle filter). However, parallel flow to the filter is considered in this study. Different face (filtration) velocities are examined using the CFD code, FLUENT. Different sizes of particles are tracked through the domain to find the height at which the particles will impinge on the filter surface. Furthermore, particle distribution around the filter (or filter cake) is studied to design efficient cleaning mechanisms. Gravity effect to the particles with various inlet velocities and pressure drop are both considered. In the CFD study, it is found that the gravity influence should not be ignored if the particle sizes exceed 1 micron.

Keywords: fluid flow, CFD, filtration, HTHP

Procedia PDF Downloads 202

Authors: H. Aminfar, M. Mohammadpourfard, K. Khajeh

Abstract:

This paper has focused on the most important parameters in the LSC uptake; inlet Re number and Sc number in the presence of non-uniform magnetic field. The magnetic field is arising from the thin wire with electric current placed vertically to the arterial blood vessel. According to the results of this study, applying magnetic field can be a treatment for atherosclerosis by reducing LSC along the vessel wall. Homogeneous porous layer as a arterial wall has been regarded. Blood flow has been considered laminar and incompressible containing Ferro fluid (blood and 4 % vol. Fe₃O₄) under steady state conditions. Numerical solution of governing equations was obtained by using the single-phase model and control volume technique for flow field.

Keywords: LDL surface concentration (LSC), magnetic field, computational fluid dynamics, porous wall

Procedia PDF Downloads 407

Authors: Yousef Barahmeh

Abstract:

There is a wide cultural belief that Jordanians are po-faced and unable to produce humour and satire. However, in the light of the harbingers of the Arab Spring in the early 2011, socio-political satire has thrived notably in social media as a rigorous act of critique and dissent against the institutionalized discourse. This paper seeks to explore the case study of Ahmad Hassan al-Zou’bi’s satirical articles and Facebook posts in the context of theories of satire and digital politics. Al-Zou’bi is the most prominent and prolific Jordanian satirist who rose to prominence after the Arab Spring. The analysis shows that his satirical articles provide a vintage point to the rhetoric behind the socio-political and economic reform programs as much as the adverse impact of neoliberal governments in the modern history of Jordan.

Keywords: Arab Spring, digital politics, humour and socio-political satire

Procedia PDF Downloads 448

Authors: Abdelaziz Moujane, Abedelali Boulli, Abdellah Ouigmane

Abstract:

The present work focuses on the assessment of forestlandscape changes in the region of ZaouitAhansal, usingmultitemporal satellite images at high spatial resolution.Severalremotesensingmethodswereappliednamely: The supervised classification algorithm and NDVI whichwerecombined in a GIS environment to quantify the extent and change in density of forest stands (holmoak, juniper, thya, Aleppo pine, crops, and others).The resultsobtainedshowedthat the forest of ZaouitAhansal has undergonesignificantdegradationresulting in a decrease in the area of juniper, cedar, and zeenoak, as well as an increase in the area of baresoil and agricultural land. The remotesensing data providedsatisfactoryresults for identifying and quantifying changes in forestcover. In addition, thisstudycould serve as a reference for the development of management strategies and restoration programs.

Keywords: remote sensing, GIS, satellite image, NDVI, deforestation, zaouit ahansal

Procedia PDF Downloads 151

Authors: Ahmed Omar Bali, Sherko Jabar, Hazhar Jalal, Mahdi Sofi-Karim

Abstract:

For a long while in Iraq, media organizations were owned by political parties, particularly the ruling parties, because media traditional organizations required big capital and human resources. This paper has examined the dynamics of Iraqi media market transformation with emphasizing on factors that help to merge media entrepreneurs and digital media firms which target audience on social media. A qualitative method was adopted in this study using open, in-depth interviews with 19 media entrepreneurs and three managers of media firms. The study revealed that relative freedom and advanced communication technologies have encouraged media entrepreneurs to drive the new media on producing short videos and broadcast them on social media which has become popular among media consumers.

Keywords: media entrepreneur, Iraq, journalists, media technicians, digital media firms, media market

Procedia PDF Downloads 302

Authors: Shreyas S. Hegde, Anindya Deb, Suresh Nagesh

Abstract:

Computational bio-mechanics is developing rapidly as a non-invasive tool to assist the medical fraternity to help in both diagnosis and prognosis of human body related issues such as injuries, cardio-vascular dysfunction, atherosclerotic plaque etc. Any system that would help either properly diagnose such problems or assist prognosis would be a boon to the doctors and medical society in general. Recently a lot of work is being focused in this direction which includes but not limited to various finite element analysis related to dental implants, skull injuries, orthopedic problems involving bones and joints etc. Such numerical solutions are helping medical practitioners to come up with alternate solutions for such problems and in most cases have also reduced the trauma on the patients. Some work also has been done in the area related to the use of computational fluid mechanics to understand the flow of blood through the human body, an area of hemodynamics. Since cardio-vascular diseases are one of the main causes of loss of human life, understanding of the blood flow with and without constraints (such as blockages), providing alternate methods of prognosis and further solutions to take care of issues related to blood flow would help save valuable life of such patients. This project is an attempt to use computational fluid dynamics (CFD) to solve specific problems related to hemodynamics. The hemodynamics simulation is used to gain a better understanding of functional, diagnostic and theoretical aspects of the blood flow. Due to the fact that many fundamental issues of the blood flow, like phenomena associated with pressure and viscous forces fields, are still not fully understood or entirely described through mathematical formulations the characterization of blood flow is still a challenging task. The computational modeling of the blood flow and mechanical interactions that strongly affect the blood flow patterns, based on medical data and imaging represent the most accurate analysis of the blood flow complex behavior. In this project the mathematical modeling of the blood flow in the arteries in the presence of successive blockages has been analyzed using CFD technique. Different cases of blockages in terms of percentages have been modeled using commercial software CATIA V5R20 and simulated using commercial software ANSYS 15.0 to study the effect of varying wall shear stress (WSS) values and also other parameters like the effect of increase in Reynolds number. The concept of fluid structure interaction (FSI) has been used to solve such problems. The model simulation results were validated using in vivo measurement data from existing literature

Keywords: computational fluid dynamics, hemodynamics, blood flow, results validation, arteries

Procedia PDF Downloads 404

Authors: S. Belgherras Bekkouche, T. Benouaz, S. M. A. Bekkouche

Abstract:

Tokamak plasma is far from having a stable background. The study of turbulent transport is an important part of the current research and advanced scenarios were devised to minimize it. To do this, we used a three-wave interaction model which allows to investigate the occurrence drift-wave turbulence driven by pressure gradients in the edge plasma of a tokamak. In order to simulate the energy redistribution among different modes, the growth/decay rates for the three waves was added. After a numerical simulation, we can determine certain aspects of the temporal dynamics exhibited by the model. Indeed for a wide range of the wave decay rate, an intermittent transition from periodic behavior to chaos is observed. Then, a control strategy of chaos was introduced with the aim of reducing or eliminating the weak turbulence.

Keywords: wave interaction, plasma drift waves, wave turbulence, tokamak, edge plasma, chaos

Procedia PDF Downloads 550

Authors: Jian-Li Shao

Abstract:

Using Molecular Dynamic (MD) simulations, we simulated the microjet from the metal surface under decaying shock loading. The microjetting processes under release melting conditions are presented in detail, and some properties on the microjet mass and velocity are revealed. The phased increase of microjet mass with shock pressure is found. For all cases, the ratio of the maximal jetting velocity to the surface velocity approximately keeps a constant for liquid state. In addition, the temperature of the microjet can be always above the melting point. When introducing slow decaying profiles, the microjet mass begins to increase with the decay rate, which is dominated by the deformation of the bubble during pull-back. When the decay rate becomes fast enough, the microspall occurs as expected, meanwhile, the microjet appears to reduce because of the shock energy reduction.

Keywords: microjetting, shock, metal, molecular dynamics

Procedia PDF Downloads 205

Authors: Kamel Barka, Lyamine Guezouli, Assem Rezki

Abstract:

In this article, we propose a protocol called DataGA-DRF (a protocol for Data collection using a Genetic Algorithm through Dynamic Reference Points) that collects data from Heterogeneous wireless sensor networks. This protocol is based on DGA (Destination selection according to Genetic Algorithm) to control the movement of the UAV (Unmanned aerial vehicle) between dynamic reference points that virtually represent the sensor node deployment. The dynamics of these points ensure an even distribution of energy consumption among the sensors and also improve network performance. To determine the best points, DataGA-DRF uses a classification algorithm such as K-Means.

Keywords: heterogeneous wireless networks, unmanned aerial vehicles, reference point, collect data, genetic algorithm

Procedia PDF Downloads 81

Authors: Thirawudh Pongprayoon, Watcharin Rassamee

Abstract:

Silica-filled natural rubber compounds were prepared from unmodified and surface-modified silica. The modified silica was coated by ultrathin film of polyisoprene by admicellar polymerization. FTIR and SEM were applied to characterize the modified silica. The cure, mechanic, and dynamics properties were investigated with the comparison of the compounds. Cure characterization of modified silica rubber compound was shorter than that of unmodified silica compound. Strength and abrasion resistance of modified silica compound were better than those of unmodified silica rubber compound. Wet grip and rolling resistance analyzed by DMA from tanδ at 0°C and 60°C using 5 Hz were also better than those of unmodified silica rubber compound.

Keywords: silica, admicellar polymerization, rubber compounds, mechanical properties, dynamic properties

Procedia PDF Downloads 348

Authors: Liang Bai, Yandong Xiao, Haorang Wang, Songyang Lao

Abstract:

The directedness of links is crucial to determine the controllability in complex networks. Even the edge directions can determine the controllability of complex networks. Obviously, for a given network, we wish to design its edge directions that make this network approach the optimal controllability. In this work, we firstly introduce two methods to enhance network by assigning edge directions. However, these two methods could not completely mitigate the negative effects of inaccessibility and dilations. Thus, to approach the optimal network controllability, the edge directions must mitigate the negative effects of inaccessibility and dilations as much as possible. Finally, we propose the edge direction for optimal controllability. The optimal method has been found to be successfully useful on real-world and synthetic networks.

Keywords: complex network, dynamics, network control, optimization

Procedia PDF Downloads 183

Authors: C. D. Ellis, H. Xia, X. Chen

Abstract:

Experimental and computational studies investigating heat transfer in separated flows have been of increasing importance over the last 60 years, as efforts are being made to understand and improve the efficiency of components such as combustors, turbines, heat exchangers, nuclear reactors and cooling channels. Understanding of not only the time-mean heat transfer properties but also the unsteady properties is vital for design of these components. As computational power increases, more sophisticated methods of modelling these flows become available for use. The hybrid LES-RANS approach has been applied to a blunt leading edge flat plate, utilising a structured grid at a moderate Reynolds number of 20300 based on the plate thickness. In the region close to the wall, the RANS method is implemented for two turbulence models; the one equation Spalart-Allmaras model and Menter’s two equation SST k-ω model. The LES region occupies the flow away from the wall and is formulated without any explicit subgrid scale LES modelling. Hybridisation is achieved between the two methods by the blending of the nearest wall distance. Validation of the flow was obtained by assessing the mean velocity profiles in comparison to similar studies. Identifying the vortex structures of the flow was obtained by utilising the λ2 criterion to identify vortex cores. The qualitative structure of the flow compared with experiments of similar Reynolds number. This identified the 2D roll up of the shear layer, breaking down via the Kelvin-Helmholtz instability. Through this instability the flow progressed into hairpin like structures, elongating as they advanced downstream. Proper Orthogonal Decomposition (POD) analysis has been performed on the full flow field and upon the surface temperature of the plate. As expected, the breakdown of POD modes for the full field revealed a relatively slow decay compared to the surface temperature field. Both POD fields identified the most energetic fluctuations occurred in the separated and recirculation region of the flow. Latter modes of the surface temperature identified these levels of fluctuations to dominate the time-mean region of maximum heat transfer and flow reattachment. In addition to the current research, work will be conducted in tracking the movement of the vortex cores and the location and magnitude of temperature hot spots upon the plate. This information will support the POD and statistical analysis performed to further identify qualitative relationships between the vortex dynamics and the response of the surface heat transfer.

Keywords: heat transfer, hybrid LES-RANS, separated and reattached flow, vortex dynamics

Procedia PDF Downloads 230

Authors: Liu-Chao Qiu

Abstract:

The damage caused by surge waves generated in water bodies by flow-like landslides can be very high in terms of human lives and economic losses. The complicated phenomena occurred in this highly unsteady process are difficult to model because three interacting phases: air, water and sediment are involved. The problem therefore is challenging since the effects of non-Newtonian fluid describing the rheology of the flow-like landslides, multi-phase flow and free surface have to be included in the simulation. In this work, the commercial computational fluid dynamics (CFD) package FLUENT is used to model the surge waves due to flow-like landslides. The comparison between the numerical results and experimental data reported in the literature confirms the accuracy of the method.

Keywords: flow-like landslide, surge wave, VOF, non-Newtonian fluids, multi-phase flows, free surface flow

Procedia PDF Downloads 415

Authors: Thanh-Phong Dao, Shyh-Chour Huang

Abstract:

This study presents a quasi-zero stiffness (QZS) vibration isolator using flexure-based spring mechanisms which afford both negative and positive stiffness elements, which enable self-adjustment. The QZS property of the isolator is achieved at the equilibrium position. A nonlinear mathematical model is then developed, based on the pre-compression of the flexure-based spring mechanisms. The dynamics are further analyzed using the Harmonic Balance method. The vibration attention efficiency is illustrated using displacement transmissibility, which is then compared with the corresponding linear isolator. The effects of parameters on performance are also investigated by numerical solutions. The flexure-based spring mechanisms are subsequently designed using the concept of compliant mechanisms, with evaluation by ANSYS software, and simulations of the QZS isolator.

Keywords: vibration isolator, quasi-zero stiffness, flexure-based spring mechanisms, compliant mechanism

Procedia PDF Downloads 457

Authors: A. Alhelfi, B. Sunden

Abstract:

Cavitation in cryogenic liquids is widely present in contemporary science. In the current study, we re-examine a previously validated acoustic cavitation model which was developed for a gas bubble in liquid water. Furthermore, simulations of cryogenic fluids including the thermal effect, the effect of acoustic pressure amplitude and the frequency of sound field on the bubble dynamics are presented. A gas bubble (Helium) in liquids Nitrogen, Oxygen and Hydrogen in an acoustic field at ambient pressure and low temperature is investigated numerically. The results reveal that the oscillation of the bubble in liquid Hydrogen fluctuates more than in liquids Oxygen and Nitrogen. The oscillation of the bubble in liquids Oxygen and Nitrogen is approximately similar.

Keywords: cryogenic liquids, cavitation, rocket engineering, ultrasound

Procedia PDF Downloads 321

Authors: Jie Bai, Yongsheng Gao, Shengxin Wang, Jie Zhao

Abstract:

Through the establishment of the elbow biomechanical model, it can provide theoretical guide for rehabilitation therapy on the upper limb of the human body. A biomechanical model of the elbow joint can be built by the connection of muscle force model and elbow dynamics. But there are many undetermined coefficients in the model like the optimal joint angle and optimal muscle force which are usually specified as the experimental parameters of other workers. Because of the individual differences, there is a certain deviation of the final result. To this end, the RMS value of the deviation between the actual angle and calculated angle is considered. A set of coefficients which lead to the minimum RMS value will be chosen to be the optimal parameters. The direct search method and the conjugacy search method are used to get the optimal parameters, thus the model can be more accurate and mode adaptability.

Keywords: elbow biomechanical model, RMS, direct search, conjugacy search

Procedia PDF Downloads 546

Authors: Hadi Adibi-Asl, Alireza Doosthosseini, Amir Taghavipour

Abstract:

This paper studies the design of an adaptive control strategy to tune an active steering system for better drivability and maneuverability. In the first step, adaptive control strategy is applied to estimate the uncertain parameters on-line (e.g. cornering stiffness), then the estimated parameters are fed into the pole placement controller to generate corrective feedback gain to improve the steering system dynamic’s characteristics. The simulations are evaluated for three types of road conditions (dry, wet, and icy), and the performance of the adaptive pole placement control (APPC) are compared with pole placement control (PPC) and a passive system. The results show that the APPC strategy significantly improves the yaw rate and side slip angle of a bicycle plant model.

Keywords: adaptive control, active steering, pole placement, vehicle dynamics

Procedia PDF Downloads 464

Authors: Ikenna Stephen Ezennia, Sebnem Onal Hoscara

Abstract:

Successive governments in Nigeria are faced with the pressing problem of how to house an ever-expanding urban population, usually low-income earners. The question of housing and affordability presents a complex challenge for these governments, as the commodification of housing links it inextricably to markets and capital flows. Therefore, placing it as at the center of the government’s agenda. However, the provision of decent and affordable housing for average Nigerians has remained an illusion, despite copious schemes, policies and programs initiated and carried out by various successive governments. Similarly, this phenomenon has also been observed in many countries of Africa, which is largely a result of economic unpredictability, lack of housing finance and insecurity, among other factors peculiar to a struggling economy. This study reviews recent dynamics and factors challenging the provision and development of affordable housing for the low income urban populace of Nigeria. Thus, the aim of the study is to present a comprehensive approach for understanding recent trends in the provision of affordable housing for Nigerians. The approach is based on a new paradigm of research: transdisciplinarity; a form of inquiry that crosses the boundaries of different disciplines. Therefore, the review takes a retrospective gaze at the various housing development programs/schemes/policies taken by successive governments of Nigeria within the last few decades and exams recent efforts geared towards eradicating the problems of housing delivery. Sources of data included relevant English language articles and the results of literature search of Elsevier Science Direct, ISI Web of Knowledge, Pro Quest Central, Scopus, and Google Scholar. The findings reveal that factors such as; rapid urbanization, inadequate planning and land use control, lack of adequate and favorable finance, high prices of land, high prices of building material, youth/touts harassment of developers, poor urban infrastructure, multiple taxation, and risk share are the major factors posing as a hindrance to adequate housing delivery. The results show that the majority of Nigeria’s affordable housing schemes, programs and policies are in most cases poorly implemented and abandoned without proper coordination. Consequently, the study concludes that the affordable housing delivery strategies in Nigeria are an epitome of lip service politics by successive governments; and the current trend of leaving housing provision to the vagaries of market forces cannot be expected to support affordable housing especially for the low income urban populace.

Keywords: affordable housing, housing delivery, national housing policy, urban poor

Procedia PDF Downloads 218

Authors: Mohd Salmi Md Noorani, Ghada Al-Mahbashi, Sakhinah Abu Bakar

Abstract:

This paper investigates projective lag synchronization (PLS) behavior in drive response dynamical networks (DRDNs) model with identical nodes. A hybrid feedback control method is designed to achieve the PLS with mismatch and without mismatch terms. The stability of the error dynamics is proven theoretically using the Lyapunov stability theory. Finally, analytical results show that the states of the dynamical network with non-delayed coupling can be asymptotically synchronized onto a desired scaling factor under the designed controller. Moreover, the numerical simulations results demonstrate the validity of the proposed method.

Keywords: drive-response dynamical network, projective lag synchronization, hybrid feedback control, stability theory

Procedia PDF Downloads 390

Authors: Arya S. S.

Abstract:

India is one of the powerful country in the world .India and Maldives having common interests in regional security and economic growth, this relationship has seen substantial change in recent years. This paper examines the complex dynamics of this bilateral relationship, emphasizing the careful balancing act that both countries perform in order to advance regional prosperity. It looks at historical connections, geopolitical factors, and current issues like economic cooperation, climate change, and marine security. The study highlights how India's involvement in the Maldives contributes to both bilateral ties and regional stability by examining important initiatives including trade agreements and infrastructure projects. It also discusses the effects of outside factors and the necessity for both nations to strategically manage their interests. In order to contribute to a more affluent and stable Indian Ocean area, this study ultimately seeks to shed light on how India and the Maldives may cooperate to promote sustainable development while tackling security issues. The India Maldives relation is very crucial in the regional stability of Indian ocean region. The initiatives like building infrastructure, giving financial support, and establishing the India-Maldives Friendship Bridge demonstrate India's dedication to Maldivian prosperity. In addition to boosting the Maldives' economy, these investments strengthen India's clout in the area, which is essential for preserving its maritime security interests in the face of growing Chinese dominance. Both India and China involved in a strategic tug of war in order to enhance their dominance in Maldives. There are difficulties with this collaboration including, political unrest in the Maldives has occasionally resulted in changes to foreign policy, particularly under regimes that support stronger ties with China. India has expressed concern about losing strategic footholds in the Indian Ocean as a result of China's extension of influence through debt diplomacy and infrastructure projects. India must therefore strike a balance between advancing its objectives and upholding Maldivian sovereignty as well as the goals of its people and government. In summary, the partnership between India and the Maldives is a complex balancing act that is marked by cultural links, security cooperation, and economic dependency. Both countries must negotiate the complexity of international relations as they work for regional prosperity, especially in light of both internal and external factors. India and the Maldives can strengthen their positions as key actors in the changing dynamics of the Indian Ocean by promoting cooperation and communication. This would not only protect their particular interests but also help create a stable and prosperous South Asian region.

Keywords: regional security, balancing act, debt trap diplomacy, strategic tug of war

Procedia PDF Downloads 14

Authors: Brian Carey Sims

Abstract:

The current study examines psychological factors relevant to child custody litigation among African American fathers. Thirty-seven fathers engaged in various stages of custody litigation involving their children were surveyed about their perceptions of racial stereotypes, parental motivations, and racialized dynamics of the court/ legal process. Data were analyzed using a Critical Race Theory model designed to statistically isolate fathers’ perceptions of the existence and maintenance of structural racism through the legal process. Results indicate significant correlations between fathers’ psychological measures and structural outcomes of their cases. Findings are discussed in terms of ethical implications for family court judicial systems and attorney practice.

Keywords: ethics, family, legal psychology, policy, race

Procedia PDF Downloads 351

Authors: Igor Astrov, Natalya Berezovski

Abstract:

This paper focuses on a critical component of the situational awareness (SA), the control of autonomous vertical flight for vectored thrust aerial vehicle (VTAV). With the SA strategy, we proposed a neural network motion control procedure to address the dynamics variation and performance requirement difference of flight trajectory for a VTAV. This control strategy with using of NARMA-L2 neurocontroller for chosen model of VTAV has been verified by simulation of take-off and forward maneuvers using software package Simulink and demonstrated good performance for fast stabilization of motors, consequently, fast SA with economy in energy can be asserted during search-and-rescue operations.

Keywords: NARMA-L2 neurocontroller, situational awareness, vectored thrust aerial vehicle, aviation

Procedia PDF Downloads 417

Authors: Laura Southgate

Abstract:

The Association of Southeast Asian Nations (ASEAN), as well as much of the scholarship on the organisation, celebrates its ability to uphold the principle of regional autonomy, understood as upholding the norm of non-intervention by external powers in regional affairs. Yet, in practice, this has been repeatedly violated. This dichotomy between rhetoric and practice suggests an interesting avenue for further study. The East Timor crisis (1975-1999) has been selected as a case-study to test the dynamics of ASEAN state resistance to sovereignty violation in two distinct timeframes: Indonesia’s initial invasion of the territory in 1975, and the ensuing humanitarian crisis in 1999 which resulted in a UN-mandated, Australian-led peacekeeping intervention force. These time-periods demonstrate variation on the dependent variable. It is necessary to observe covariation in order to derive observations in support of a causal theory. To establish covariation, my independent variable is therefore a continuous variable characterised by variation in convergence of interest. Change of this variable should change the value of the dependent variable, thus establishing causal direction. This paper investigates the history of ASEAN’s relationship to the norm of non-intervention. It offers an alternative understanding of ASEAN’s history, written in terms of the relationship between a key ASEAN state, which I call a ‘vanguard state’, and selected external powers. This paper will consider when ASEAN resistance to sovereignty violation has succeeded, and when it has failed. It will contend that variation in outcomes associated with vanguard state resistance to sovereignty violation can be best explained by levels of interest convergence between the ASEAN vanguard state and designated external actors. Evidence will be provided to support the hypothesis that in 1999, ASEAN’s failure to resist violations to the sovereignty of Indonesia was a consequence of low interest convergence between Indonesia and the external powers. Conversely, in 1975, ASEAN’s ability to resist violations to the sovereignty of Indonesia was a consequence of high interest convergence between Indonesia and the external powers. As the vanguard state, Indonesia was able to apply pressure on the ASEAN states and obtain unanimous support for Indonesia’s East Timor policy in 1975 and 1999. However, the key factor explaining the variance in outcomes in both time periods resides in the critical role played by external actors. This view represents a serious challenge to much of the existing scholarship that emphasises ASEAN’s ability to defend regional autonomy. As these cases attempt to show, ASEAN autonomy is much more contingent than portrayed in the existing literature.

Keywords: ASEAN, east timor, intervention, sovereignty

Procedia PDF Downloads 357

Authors: Edmilson Nhambe, Belisario Machaieie

Abstract:

Since the signing of the General Peace Agreement-GPA in 1992, Mozambique has seen successive setbacks in the search for effective peace, civil war, social conflicts, terrorism, and armed conflicts mix the reality of Mozambican democracy. The article seeks to understand the dynamics of conflict and peace in Mozambique. Specifically, it seeks to analyze the structural factors that lead to (violent) conflict situations and the factors that favor or promote peace. For this purpose, desk research was chosen to analyze studies of peace and conflict. This article develops the argument that the non-violation of the peace agreement, in particular the GPA in Rome, as it had a structuring effect on the Mozambican political system, no longer guarantees in itself the irreversibility of the pacification process. In fact, the country is currently stagnating in the category of a fragile peace process with the risk of slipping into a situation of war or open armed conflict.

Keywords: peace, conflict, GPA, instability

Procedia PDF Downloads 197

Authors: Mengqi Zhu, Chang Nyung Kim

Abstract:

This study numerically investigates three-dimensional liquid-metal (LM) magnetohydrodynamic (MHD) flows in a misaligned duct under a uniform magnetic field. The duct consists of two misaligned horizontal channels (one is inflow channel, the other is outflow channel) and one central vertical channel. Computational fluid dynamics simulations are performed to predict the behavior of the MHD flows, using commercial code CFX. In the current study, a case with Hartmann number 1000 is considered. The electromagnetic features of LM MHD flows are elucidated to examine the interdependency of the flow velocity, current density, electric potential, pressure drop and Lorentz force. The results show that pressure decreases linearly along the main flow direction.

Keywords: CFX, liquid-metal magnetohydrodynamic flows, misaligned duct, pressure drop

Procedia PDF Downloads 283

Authors: Sergey Kuznetsov, Yuri Urman

Abstract:

We present an approach to investigate non-linear dynamical effects occurring in the noncontact superconducting and diamagnetic suspensions, when levitated body has finite size. This approach is based on the calculation of interaction energy between spherical finite size superconducting or diamagnetic body with external magnetic field. Effects of small deviations from spherical shape may be also taken into account by introducing small corrections to the energy. This model allows investigating dynamical effects important for practical applications, such as nonlinear resonances, change of vibration plane, coupling of rotational and translational motions etc. We also show how the geometry of suspension affects various dynamical effects and how an inverse problem may be formulated to enforce or diminish various dynamical effects.

Keywords: levitation, non-linear dynamics, superconducting, diamagnetic stability

Procedia PDF Downloads 408

Authors: Arpit Sachan, Nilanshu Kumar

Abstract:

This paper tries to understand the nuances of feminisation of agriculture in the Indian context and how that is associated with better intrahousehold bargaining power for women. The economic survey of India indicates a constant increase in the share of the female workforce in Indian agriculture in the past few decades. This can be accounted for by many factors like the migration of male workers to urban areas and, therefore, the complete burden of agriculture shifting on the female counterparts. Therefore this study is an attempt to study that how this increase in the female workforce corresponds to a better decision-making ability for women in rural farm households. This paper is an attempt to carefully evaluate this aspect of the feminisation of Indian agriculture. The paper tries to study how various factors that improve the status of women in agriculture change with things like resource ownership. This paper uses both the macro-level and micro-level data to study the dynamics of the proportion of the workforce in agriculture across different states in India and how that has translated into better indicators for women in rural areas. The fall in India’s rank in the global gender wage gap index is alarming in such a context, and this creates a puzzle with increasing female workforce participation. The paper will consider if the condition of women improved over time with the increased share of employment or not? Using field survey data, this paper tries to understand if there exists any digression for some of the indicators both at the macro and micro level. The paper also tries to integrate the economic understanding of gender aspects of the workforce and the sociological stance prevailing in the existing literature. Therefore, this paper takes a mixed-method approach to better understand the role that social structure plays in the improved status of women within and across various households. Therefore, this paper will finally help us understanding if at all there is a feminisation of Indian agriculture or it's just exploitation of a different kind. This study intends to create a distinction between the gendered labour force in Indian agriculture and the complete democratization of Indian agriculture. The study is primarily focused on areas where the exodus of male migrants pushes women to work on agricultural farms. The question posits is whether it is the willingness of women to work in agriculture or is it urbanisation and development-induced conditions that make women work in agriculture as farm labourers? The motive is to understand if factors like resource ownership and the ability to autonomous decision-making are interlinked with an increased proportion of the female workforce or not? Based on this framework, we finally provide a brief comment on policy implications of government intervention in improving Indian agriculture and the gender aspects associated with it.

Keywords: feminisation, intrahousehold bargaining, farm households, migration, agriculture, decision-making

Procedia PDF Downloads 129

Authors: Sachin Aggarwal, Sarah Kassinger, Nicholas Hoffman

Abstract:

Geometry simplification is a key step in performing conjugate heat transfer analysis using CFD. This paper proposes a standard methodology for the geometry simplification of rotating machines, such as electrical generators and electrical motors (both air and liquid-cooled). These machines are extensively deployed throughout the aerospace and automotive industries, where optimization of weight, volume, and performance is paramount -especially given the current global transition to renewable energy sources and vehicle hybridization and electrification. Conjugate heat transfer analysis is an essential step in optimizing their complex design. This methodology will help in reducing convergence issues due to poor mesh quality, thus decreasing computational cost and overall analysis time.

Keywords: CFD, electrical machines, Geometry simplification, heat transfer

Procedia PDF Downloads 129