Search results for: trade gravity model
17580 A Predictive Model of Supply and Demand in the State of Jalisco, Mexico
Authors: M. Gil, R. Montalvo
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Business Intelligence (BI) has become a major source of competitive advantages for firms around the world. BI has been defined as the process of data visualization and reporting for understanding what happened and what is happening. Moreover, BI has been studied for its predictive capabilities in the context of trade and financial transactions. The current literature has identified that BI permits managers to identify market trends, understand customer relations, and predict demand for their products and services. This last capability of BI has been of special concern to academics. Specifically, due to its power to build predictive models adaptable to specific time horizons and geographical regions. However, the current literature of BI focuses on predicting specific markets and industries because the impact of such predictive models was relevant to specific industries or organizations. Currently, the existing literature has not developed a predictive model of BI that takes into consideration the whole economy of a geographical area. This paper seeks to create a predictive model of BI that would show the bigger picture of a geographical area. This paper uses a data set from the Secretary of Economic Development of the state of Jalisco, Mexico. Such data set includes data from all the commercial transactions that occurred in the state in the last years. By analyzing such data set, it will be possible to generate a BI model that predicts supply and demand from specific industries around the state of Jalisco. This research has at least three contributions. Firstly, a methodological contribution to the BI literature by generating the predictive supply and demand model. Secondly, a theoretical contribution to BI current understanding. The model presented in this paper incorporates the whole picture of the economic field instead of focusing on a specific industry. Lastly, a practical contribution might be relevant to local governments that seek to improve their economic performance by implementing BI in their policy planning.Keywords: business intelligence, predictive model, supply and demand, Mexico
Procedia PDF Downloads 12317579 Banking Crisis and Economic Effects of the Banking Crisis in Turkey
Authors: Sevilay Konya, Sadife Güngör, Zeynep Karaçor
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Turkish economy is occurred depending on different factors from time to time and the banking crises of different magnitudes. Foremost among the factors which hinder the development of countries and societies- crises in the country's economy. Countries' economic growth rates affect inflation, unemployment and external trade. In this study, effect of November 2000, February 2001 and 2008 banking crisis on Turkey's economy and banking crisis will be examined and announced as conceptual. In this context, this study is investigates Turkey's GDP, inflation, unemployment and foreign trade figures. Turkey's economy affected have been identified from 2000 November 2001 February and 2008 banking crisis.Keywords: banking crises, Turkey’s economy, economic effects, Turkey
Procedia PDF Downloads 29617578 River Bank Erosion Studies: A Review on Investigation Approaches and Governing Factors
Authors: Azlinda Saadon
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This paper provides detail review on river bank erosion studies with respect to their processes, methods of measurements and factors governing river bank erosion. Bank erosion processes are commonly associated with river changes initiation and development, through width adjustment and planform evolution. It consists of two main types of erosion processes; basal erosion due to fluvial hydraulic force and bank failure under the influence of gravity. Most studies had only focused on one factor rather than integrating both factors. Evidences of previous works have shown integration between both processes of fluvial hydraulic force and bank failure. Bank failure is often treated as probabilistic phenomenon without having physical characteristics and the geotechnical aspects of the bank. This review summarizes the findings of previous investigators with respect to measurement techniques and prediction rates of river bank erosion through field investigation, physical model and numerical model approaches. Factors governing river bank erosion considering physical characteristics of fluvial erosion are defined.Keywords: river bank erosion, bank erosion, dimensional analysis, geotechnical aspects
Procedia PDF Downloads 43617577 Simulation and Control of the Flywheel System in the Rotor of a Wind Turbine Using Simulink and OpenFAST for Assessing the Effect on the Mechanical Loads
Authors: Chinazo Onyeka Eziuzo
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This work presents the simulation and control of the flywheel system in the rotor of a wind turbine using Simulink and OpenFAST for assessing the effect on the mechanical loads. This concept allows the flywheel system to serve two main tasks: supporting the power system and mitigating the mechanical loads in the wind turbine. These tasks are grouped into four control scenarios; scenario 1 represents steadying the power infeed in the Flywheel, scenario 2 represents steadying power with FW and grid loss, scenario 3 represents mitigating excitations from gravity, and scenario 4 represents damping in-plane blade vibrations. The s-function of the OpenFAST model was used to substitute the given 1st Eigen mode model of the WT. After that, the simulations were run for the above-listed scenarios. Additionally, the effects of the control options on the mechanical loads were assessed, and it was established that the FW system assists in steadying infeed power and mechanical load mitigation.Keywords: simulation, control, wind turbine, OpenFAST
Procedia PDF Downloads 12917576 The Impact of Information Communication Technology on Promoting Travel Trade Industry in a Developing Economy, Case Study Nigeria
Authors: Murtala Mohammed Alamai, Abdullahi Marshal Idris, Adama Idris
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Today, marketing does not only involve selecting target markets, but it also involves communicating with the customers through various means to put across your selling point. Modern marketing involves driving new product development based on customer needs by getting feedback from them. Utilizing the latest technology for better communication with the customers is the latest advancement in Marketing in the 21st century. The survey approach was used where a sample of tourist destinations across the six geographical zones of the country at random was done to ascertain the use of information communication systems in promoting their products and or services, the findings revealed that only a few utilize these modern advanced means in marketing and promoting their products and a need to develop effective and up to date online services for marketing was proffered as solutions to the findings observed.Keywords: information, communication, travel, trade, promotion
Procedia PDF Downloads 32417575 The Developing Method of Supply Chain Economy in Eurasia and North America
Authors: Tae Ho Kim
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Using the center of gravity method, we intend to find the center of gravity of Eurasia and North America, focusing on the local population, and study economic development plans in Eurasia and North America. By analyzing the strengths and opportunities of an industrial location for each region, we find ways for the country to grow and develop. Through economic cooperation and support between countries, we want to reduce the cause of conflict and dispute through economic growth in countries or regions. Furthermore, we want to create conditions for peaceful and happy regions or countries. Eurasia and North America are rich in resources, have great growth potential in terms of global supply chains, and have a good position to develop further. By analyzing intimacy between countries using REM, a CRM method, we intend to transform it into a region where a hopeful future of peace and prosperity begins. The future can be transformed through positive thinking or love for humanity. Indicators of intimacy between countries or regions can also be created anew if they change how they view each other. The Earth we live on is facing great risks, such as climate change and war. In order to reduce this crisis and maintain peace and prosperity, we must cooperate with each other in new directions.Keywords: supply chain economy, REM, Indicators of intimacy, peace and prosperity
Procedia PDF Downloads 7017574 Three Dimensional Flexible Dynamics of Continuous Cislunar Payloads Transfer System
Authors: Y. Yang, Dian Ming Xing, Qiu Hua Du
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Based on the Motorized Momentum Exchange Tether (MMET), with the principle of momentum exchange, the three dimension flexible dynamics of continuous cislunar payloads transferring system (CCPTS) is built by Lagrange method and its numerical solution is solved by Mathematica software. In the derivation precession of potential energy, this paper uses the Tylor expansion method to simplify the Lagrange equation. Furthermore, the tension coming from the centripetal load is considered in the elastic potential energy. The comparison simulation results between the 3D rigid model and 3D flexible model of CCPTS shows that the tether flexibility has important influence on CCPTS’s orbital parameters (such as radius of CCPTS’s COM and the true anomaly) and the tether’s rotational movement, the relative deviation of radius and the true anomaly between the two dynamic models is about 0.00678% and 0.00259%, the relative deviation of the angle of tether-span and local gravity gradient is about 3.55%. Additionally, the external torque has an apparent influence on the tether’s axial vibration.Keywords: cislunar transfer, dynamics, momentum exchange, tether
Procedia PDF Downloads 26917573 Current Starved Ring Oscillator Image Sensor
Authors: Devin Atkin, Orly Yadid-Pecht
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The continual demands for increasing resolution and dynamic range in CMOS image sensors have resulted in exponential increases in the amount of data that needs to be read out of an image sensor, and existing readouts cannot keep up with this demand. Interesting approaches such as sparse and burst readouts have been proposed and show promise, but at considerable trade-offs in other specifications. To this end, we have begun designing and evaluating various new readout topologies centered around an attempt to parallelize the sensor readout. In this paper, we have designed, simulated, and started testing a new light-controlled oscillator topology with dual column and row readouts. We expect the parallel readout structure to offer greater speed and alleviate the trade-off typical in this topology, where slow pixels present a major framerate bottleneck.Keywords: CMOS image sensors, high-speed capture, wide dynamic range, light controlled oscillator
Procedia PDF Downloads 9017572 Lessons from Vernacular Architecture for Lightweight Construction
Authors: Alireza Taghdiri, Sara Ghanbarzade Ghomi
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With the gravity load reduction in the structural and non-structural components, the lightweight construction will be achieved as well as the improvement of efficiency and functional specifications. The advantages of lightweight construction can be examined in two levels. The first is the mass reduction of load bearing structure which results in increasing internal useful space and the other one is the mass reduction of building which decreases the effects of seismic load as a result. In order to achieve this goal, the essential building materials specifications and also optimum load bearing geometry of structural systems and elements have to be considered, so lightweight materials selection particularly with lightweight aggregate for building components will be the first step of lightweight construction. In the next step, in addition to selecting the prominent samples of Iran's traditional architecture, the process of these works improvement is analyzed through the viewpoints of structural efficiency and lightweighting and also the practical methods of lightweight construction have been extracted. The optimum design of load bearing geometry of structural system has to be considered not only in the structural system elements, but also in their composition and the selection of dimensions, proportions, forms and optimum orientations, can lead to get a maximum materials efficiency for loads and stresses bearing.Keywords: gravity load, light-weighting structural system, load bearing geometry, seismic behavior
Procedia PDF Downloads 54717571 Modifying Hawking Radiation in 2D-Approximated Schwarzschild Black Holes near the Event Horizon
Authors: Richard Pincak
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Starting from a 4D spacetime model using a partially negative dimensional product manifold (PNDP-manifold), which emerges as a 2D spacetime, we developed an analysis of tidal forces and Hawking radiation near the event horizon of a Schwarzchild black hole. The modified 2D metric, incorporating the effects of the four-dimensional Weyl tensor, with the dilatonic field and the newly derived time relation \(2\alpha t = \ln \epsilon\), can enable a deeper understanding of quantum gravity. The analysis shows how the modified Hawking temperature and distribution of emitted particles are affected by additional fields, providing potential observables for future experiments.Keywords: black holes, Hawking radiation, Weyl tensor, information paradox
Procedia PDF Downloads 2217570 Software Tool Design for Heavy Oil Upgrading by Hydrogen Donor Addition in a Hydrodynamic Cavitation Process
Authors: Munoz A. Tatiana, Solano R. Brandon, Montes C. Juan, Cierco G. Javier
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The hydrodynamic cavitation is a process in which the energy that the fluids have in the phase changes is used. From this energy, local temperatures greater than 5000 °C are obtained where thermal cracking of the fluid molecules takes place. The process applied to heavy oil affects variables such as viscosity, density, and composition, which constitutes an important improvement in the quality of crude oil. In this study, the need to design a software through mathematical integration models of mixing, cavitation, kinetics, and reactor, allows modeling changes in density, viscosity, and composition of a heavy oil crude, when the fluid passes through a hydrodynamic cavitation reactor. In order to evaluate the viability of this technique in the industry, a heavy oil of 18° API gravity, was simulated using naphtha as a hydrogen donor at concentrations of 1, 2 and 5% vol, where the simulation results showed an API gravity increase to 0.77, 1.21 and 1.93° respectively and a reduction viscosity by 9.9, 12.9 and 15.8%. The obtained results allow to have a favorable panorama on this technological development, an appropriate visualization on the generation of innovative knowledge of this technique and the technical-economic opportunity that benefits the development of the hydrocarbon sector related to heavy crude oil that includes the largest world oil production.Keywords: hydrodynamic cavitation, thermal cracking, hydrogen donor, heavy oil upgrading, simulator
Procedia PDF Downloads 15117569 Role of International Organizations towards Good Governance: Recent Trends
Authors: E. Prema Shyam
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The role of international organizations has contributed in various ways for the good governance in the world at large. Since the beginning of the 1990s international organizations, particularly those active in the areas of human rights, trade and economic etc., have embraced a 'good governance'. It is also pertinent to mention that the application of the concept of good governance to international organizations themselves and not exclusively to national or regional polities is a more recent phenomenon. Especially since the second half of the 1990s, a number of international organizations have carried out major governance reforms, assuming that their calls for governments to heed higher standards of good governance will be all the more credible provided that they develop a good governance standard for themselves. In addition to this number of organizations such as the United Nations (UN), Organisation for Economic Co-operation and Development (OECD), European Union (EU), International Committee of the Red Cross and World Trade Organization (WTO). OECD has been specifically mobilized to fight corruption. The World Bank was the first international organization to address the issue of good governance when it attributed the African development crisis to a crisis of governance in a 1989 report. International organizations are often denounced for their lack of transparency and democracy. However, in the last few years, a number of them have pushed through impressive reforms aimed at enhancing good governance standards within their own organizations, especially in the light of their long-standing secrecy. This is a remnant of the traditional conception of international organizations, which renders them merely answerable to their Members. International organizations have already gone quite some way in the areas of good management and opening up to the public. However, as far as participatory governance is concerned, lot to be done for the larger interest of society. In this paper, an attempt has been made to focus the issues on international organisations with regard to good governance.Keywords: good governance, World Trade Organisation, international organisation, governance reforms
Procedia PDF Downloads 45417568 Design of Effective Decoupling Point in Build-To-Order Systems: Focusing on Trade-Off Relation between Order-To-Delivery Lead Time and Work in Progress
Authors: Zhiyong Li, Hiroshi Katayama
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Since 1990s, e-commerce and internet business have been grown gradually over the word and customers tend to express their demand attributes in terms of specification requirement on parts, component, product structure etc. This paper deals with designing effective decoupling points for build to order systems under e-commerce environment, which can be realized through tradeoff relation analysis between two major criteria, customer order lead time and value of work in progress. These KPIs are critical for successful BTO business, namely time-based service effectiveness on coping with customer requirements for the first issue and cost effective ness with risk aversive operations for the second issue. Approach of this paper consists of investigation of successful business standing for BTO scheme, manufacturing model development of this scheme, quantitative evaluation of proposed models by calculation of two KPI values under various decoupling point distributions and discussion of the results brought by pattern of decoupling point distribution, where some cases provide the pareto optimum performances. To extract the relevant trade-off relation between considered KPIs among 2-dimensional resultant performance, useful logic developed by former research work, i.e. Katayama and Fonseca, is applied. Obtained characteristics are evaluated as effective information for managing BTO manufacturing businesses.Keywords: build-to-order (BTO), decoupling point, e-commerce, order-to-delivery lead time (ODLT), work in progress (WIP)
Procedia PDF Downloads 32617567 Influence of Produced Water Mixed With Crude Oil on the Geotechnical Properties of Sandy Soil
Authors: Khalifa Abdunaser
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This study investigated the effects of oil contamination due to pro-duced water leaks that created lakes decades ago, as well as the extent of its im-pact on altering the geotechnical characteristics of the soil, which could act as a barrier to groundwater access The concentration of total petroleum hydrocarbons (TPH), which is the main component in the contaminated soil, was measured using a variety of analyses. Additionally, some extensive laboratory tests were performed to examine the effects on the soil's geotechnical properties, including particle size distribution, shear strength, consistency limits, specific gravity, and permeability coefficient. A clear decrease in TPH concentration was observed with increasing depth, and it is expected to end within only a few meters. It was found that there is a signifi-cant effect of this pollutant on the size of the soil particles, which led to them be-coming coarser than the uncontaminated soil particles. Moreover, it causes a de-crease in fluid and plastic boundaries, as well as an increase in cohesion between soil particles. However, the angle of internal friction decreases with the increase in the content of petroleum hydrocarbons in the soil samples. It came to light that determining the permeability coefficient as one of the physical characteristics of the most important factors responsible for the passage of pollutants in the groundwater, as it showed an obvious reduction in the permeability, which is the main reason dealt as an obstacle to the arrival of oil pollutants to the groundwater.Keywords: TPH, specific gravity, oil lake, Libya
Procedia PDF Downloads 9417566 Recognition and Enforcement of Foreign Arbitral Awards in Nepal
Authors: Biraj Puri, Bikram Puri
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Arbitration is one of the prompt and efficient methods of alternative dispute resolution, especially of a commercial nature, by a neutral arbitrator outside the formal court structure. Due to the globalization of trade, privatization, and global investment, recognition and enforcement of foreign arbitral awards attract prime concern. Arbitral awards are generally based on arguments and evidence presented by disputing parties. The foreign investor wants to secure the investment by appropriate legal measures and an amicable way of dispute settlement if it arises. Now, arbitration as a mechanism of commercial dispute settlement has gained international recognition. It can take place in any State, in any language and with arbitrators of any nationality. There are various international institutions to conduct arbitral proceedings and render awards. Once an arbitral award is delivered, it can be enforced as a court judgment. However, it is really challenging to execute foreign arbitral awards in Nepal. Any party willing to execute an award made in a foreign country in Nepal should submit an application to the High Court along with essential documents prescribed by domestic law (The Arbitration Act 1999). Arbitrarily and public policy are also the requirements regarding the recognition and enforcement of foreign arbitral awards in Nepal. Nepal is a signatory State to the New York Convention on Recognition and Enforcement of Foreign Arbitral Awards, 1958. It is crucial to acknowledge that Nepal has liberalized its economy as well as opened the door for a liberal and market-oriented economy through the Constitution of Nepal, 2015. Nepal is trying to expand business from local to global level. Commercial trade is expanding day by day. So in this context, acceptance of arbitration as an alternative means to solve commercial disputes is a matter of prime importance. India ratified the New York Convention, and also being a neighborhood country of Nepal, in practice, does not enforce arbitral awards provided by Nepal in the name of reservation. India has published a gazette notice in which it lists the countries in which the award will be recognized in India, but it does not include Nepal. As the largest trade partner of Nepal, India should rethink this in order to make trade smooth.Keywords: commercial arbitration, foreign arbitral awards, recognition and enforcement of foreign arbitral awards, requirements
Procedia PDF Downloads 517565 Applied Methods for Lightweighting Structural Systems
Authors: Alireza Taghdiri, Sara Ghanbarzade Ghomi
Abstract:
With gravity load reduction in the structural and non-structural components, the lightweight construction will be achieved as well as the improvement of efficiency and functional specifications. The advantages of lightweight construction can be examined in two levels. The first is the mass reduction of load bearing structure which results in increasing internal useful space and the other one is the mass reduction of building which decreases the effects of seismic load as a result. In order to achieve this goal, the essential building materials specifications and also optimum load bearing geometry of structural systems and elements have to be considered, so lightweight materials selection particularly with lightweight aggregate for building components will be the first step of lightweight construction. In the next step, in addition to selecting the prominent samples of Iran's traditional architecture, the process of these works improvement is analyzed through the viewpoints of structural efficiency and lightweighting and also the practical methods of lightweight construction have been extracted. The optimum design of load bearing geometry of structural system has to be considered not only in the structural system elements, but also in their composition and the selection of dimensions, proportions, forms and optimum orientations, can lead to get a maximum materials efficiency for loads and stresses bearing.Keywords: gravity load, lightweighting structural system, load bearing geometry, seismic behavior
Procedia PDF Downloads 52417564 The Imperative of Indigenous Entrepreneurship and Sustainable Development in the Globalized Economy
Authors: Innocent Felix Idoko
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The development of indigenous entrepreneurship is critical to the achievement of sustainable development in the internationalized economy. Sustainable development implies a continuous stimulus of growth and improvement of an economy in a fairly stable manner. The paradigms of a globalization are numerous to mention. However, to a great extent, these are trade-offs and dilemmas for indigenous entrepreneurship, particularly in the developing economies with infant industries that are essentially crucial to development. This paper analyses the pros and cons of globalization as relates to the complementary role of both foreign and indigenous entrepreneurs, the conflict of values between globalization and protectionism for local entrepreneurship. Using analytical and descriptive approach, the views of academicians, research fellows, literature reviews and both the theories of the mercantilists and those of free trade mainstream economists, and the G20, the paper concludes that there is a legitimate need for protectionism for domestic entrepreneurship in the developing economies as doing otherwise amount to stifling them.Keywords: developing countries, entrepreneurship, globalization, infant-industries, protectionism, sustainable development
Procedia PDF Downloads 45017563 A Simulation Model to Analyze the Impact of Virtual Responsiveness in an E-Commerce Supply Chain
Authors: T. Godwin
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The design of a supply chain always entails the trade-off between responsiveness and efficiency. The launch of e-commerce has not only changed the way of shopping but also altered the supply chain design while trading off efficiency with responsiveness. A concept called ‘virtual responsiveness’ is introduced in the context of e-commerce supply chain. A simulation model is developed to compare actual responsiveness and virtual responsiveness to the customer in an e-commerce supply chain. The simulation is restricted to the movement of goods from the e-tailer to the customer. Customer demand follows a statistical distribution and is generated using inverse transformation technique. The two responsiveness schemes of the supply chain are compared in terms of the minimum number of inventory required at the e-tailer to fulfill the orders. Computational results show the savings achieved through virtual responsiveness. The insights gained from this study could be used to redesign e-commerce supply chain by incorporating virtual responsiveness. A part of the achieved cost savings could be passed back to the customer, thereby making the supply chain both effective and competitive.Keywords: e-commerce, simulation modeling, supply chain, virtual responsiveness
Procedia PDF Downloads 34517562 Maximizing Profit Using Optimal Control by Exploiting the Flexibility in Thermal Power Plants
Authors: Daud Mustafa Minhas, Raja Rehan Khalid, Georg Frey
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The next generation power systems are equipped with abundantly available free renewable energy resources (RES). During their low-cost operations, the price of electricity significantly reduces to a lower value, and sometimes it becomes negative. Therefore, it is recommended not to operate the traditional power plants (e.g. coal power plants) and to reduce the losses. In fact, it is not a cost-effective solution, because these power plants exhibit some shutdown and startup costs. Moreover, they require certain time for shutdown and also need enough pause before starting up again, increasing inefficiency in the whole power network. Hence, there is always a trade-off between avoiding negative electricity prices, and the startup costs of power plants. To exploit this trade-off and to increase the profit of a power plant, two main contributions are made: 1) introducing retrofit technology for state of art coal power plant; 2) proposing optimal control strategy for a power plant by exploiting different flexibility features. These flexibility features include: improving ramp rate of power plant, reducing startup time and lowering minimum load. While, the control strategy is solved as mixed integer linear programming (MILP), ensuring optimal solution for the profit maximization problem. Extensive comparisons are made considering pre and post-retrofit coal power plant having the same efficiencies under different electricity price scenarios. It concludes that if the power plant must remain in the market (providing services), more flexibility reflects direct economic advantage to the plant operator.Keywords: discrete optimization, power plant flexibility, profit maximization, unit commitment model
Procedia PDF Downloads 14417561 Film Review of 'Heroic Saviours and Survivors': The Representation of Sex Trafficking in Popular Films in India
Authors: Nisha James, Shubha Ranganathan
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One of the most poignant forms of organized crime against women, which has rarely made it to the world of Indian cinema, is that of sex trafficking, i.e. the forcible involvement of women in the sex trade through fraud or coercion (Hughes, 2005). In the space of Indian cinema, much of the spotlight has been on the sensational drug trafficking and gang mafia of Bombay. During our research on sex trafficking, the rehabilitated women interviewed often expressed strong criticism about mass media’s naive portrayal of prostitutes as money-minting, happy and sexually driven women. They argued that this unrealistic portrayal ignored the fact that this was not a reality for the majority of trafficked women. Given the gravity of sex trafficking as a human rights issue, it is, therefore, refreshing to see three recent films on sex trafficking in Indian Languages – Naa Bangaaru Talli (2014, Telugu), Mardaani (2014, Hindi) and Lakshmi (2014, Hindi). This paper reviews these three films to explore the portrayal of the everyday reality of trafficking for women. Film analysis was used to understand the representation of psychological issues in the media. The strength of these movies starts with their inspirations which are of true stories and that they are all aimed at bringing awareness about the issue of sex trafficking, which is a rising social evil in Indian society though none of the three films move to portray the next phase of rehabilitation and reintegration of victims, which is a very complex and important process in the life of a survivor. According to findings, survivors of sex trafficking find the rehabilitation and reintegration into society to be a slow and tough part of their life as they continuously face stigma and social exclusion and have to strive to live against all odds of non-acceptance starting from their family.Keywords: film review, Indian films, sex trafficking, survivors
Procedia PDF Downloads 44017560 Covariance and Quantum Cosmology: A Comparison of Two Matter Clocks
Authors: Theodore Halnon, Martin Bojowald
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In relativity, time is relative between reference frames. However, quantum mechanics requires a specific time coordinate in order to write an evolution equation for wave functions. This difference between the two theories leads to the problem of time in quantum gravity. One method to study quantum relativity is to interpret the dynamics of a matter field as a clock. In order to test the relationship between different reference frames, an isotropic cosmological model with two matter ingredients is introduced. One is given by a scalar field and one by vacuum energy or a cosmological constant. There are two matter fields, and thus two different Hamiltonians are derived from the respective clock rates. Semi-classical solutions are found for these equations and a comparison is made of the physical predictions that they imply.Keywords: cosmology, deparameterization, general relativity, quantum mechanics
Procedia PDF Downloads 30817559 Percolation Transition in an Agglomeration of Spherical Particles
Authors: Johannes J. Schneider, Mathias S. Weyland, Peter Eggenberger Hotz, William D. Jamieson, Oliver Castell, Alessia Faggian, Rudolf M. Füchslin
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Agglomerations of polydisperse systems of spherical particles are created in computer simulations using a simplified stochastic-hydrodynamic model: Particles sink to the bottom of the cylinder, taking into account gravity reduced by the buoyant force, the Stokes friction force, the added mass effect, and random velocity changes. Two types of particles are considered, with one of them being able to create connections to neighboring particles of the same type, thus forming a network within the agglomeration at the bottom of a cylinder. Decreasing the fraction of these particles, a percolation transition occurs. The critical regime is determined by investigating the maximum cluster size and the percolation susceptibility.Keywords: binary system, maximum cluster size, percolation, polydisperse
Procedia PDF Downloads 6117558 Heat and Mass Transfer Study of Supercooled Large Droplet Icing
Authors: Du Yanxia, Stephan E. Bansmer, Gui Yewei, Xiao Guangming, Yang Xiaofeng
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The heat and mass transfer characteristics of icing coupled with film flow is studied and the coupled model of the thermal behavior with the flow simulation by single-step method is developed. The behavior of ice and water was analyzed. The results show that under supercooled large droplet (SLD) icing conditions, the film flow is an important phonomena in icing accretion process. The pressure gradient, gravity and shear stress are the main factors affecting the film flow on icing surface, which has important influence on the shape and rate of icing. To predict SLD ice accretion accurately, the heat and mass transfer of ice and film flow should be taken into account.Keywords: SLD, aircraft, icing, heat and mass transfer
Procedia PDF Downloads 63417557 Assimilating Multi-Mission Satellites Data into a Hydrological Model
Authors: Mehdi Khaki, Ehsan Forootan, Joseph Awange, Michael Kuhn
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Terrestrial water storage, as a source of freshwater, plays an important role in human lives. Hydrological models offer important tools for simulating and predicting water storages at global and regional scales. However, their comparisons with 'reality' are imperfect mainly due to a high level of uncertainty in input data and limitations in accounting for all complex water cycle processes, uncertainties of (unknown) empirical model parameters, as well as the absence of high resolution (both spatially and temporally) data. Data assimilation can mitigate this drawback by incorporating new sets of observations into models. In this effort, we use multi-mission satellite-derived remotely sensed observations to improve the performance of World-Wide Water Resources Assessment system (W3RA) hydrological model for estimating terrestrial water storages. For this purpose, we assimilate total water storage (TWS) data from the Gravity Recovery And Climate Experiment (GRACE) and surface soil moisture data from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) into W3RA. This is done to (i) improve model estimations of water stored in ground and soil moisture, and (ii) assess the impacts of each satellite of data (from GRACE and AMSR-E) and their combination on the final terrestrial water storage estimations. These data are assimilated into W3RA using the Ensemble Square-Root Filter (EnSRF) filtering technique over Mississippi Basin (the United States) and Murray-Darling Basin (Australia) between 2002 and 2013. In order to evaluate the results, independent ground-based groundwater and soil moisture measurements within each basin are used.Keywords: data assimilation, GRACE, AMSR-E, hydrological model, EnSRF
Procedia PDF Downloads 29117556 Effect of Inclusion of Rubber on the Compaction Characteristics of Cement - MSWIFA- Clayey Soil Mixtures
Authors: Gehan Aouf, Diala Tabbal, Abd El Rahim Sabsabi, Rashad Aouf
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The aim of this study is to show the effect of adding cement municipal solid incineration fly ash and rubber as stabilizer materials on weak soil. A detailed experimental study was conducted in order to show the viability of using these admixtures in improving the maximum dry density and optimum moisture content of the composite soil. Soil samples were prepared by adding Rubber and Cement to municipal solid waste incineration fly-ash - oil mix at different percentages. Then, a series of laboratory tests were performed, namely: Sieve analysis, Atterberg limits tests, Unconfined compression test, and Proctor tests. Three different percentages of fly ash (10%, 20%, and 30%) MSWFA by total dry weight of soil and three different percentages of Portland cement (10%, 15%, and 20%) by total dry weight of the mix and 0%, 5%, 10% for Rubber by total dry weight of the mix were used to find the optimum value. The test results reveal that adding MSWIFA to the soil up to 20% increased the MDD of the mixture and decreased the OMC, then an opposite trend for results were found when the percentage of MSWIFA exceeded 20%. This is due to the low specific gravity of MSWIFA and to the greater water absorption of MSWIFA. The laboratory tests also indicate that adding Rubber to the mix Soil-MSWIFA-Cement decreases its MDD due to the low specific gravity of rubber and it affects a slight decrease in OMC because the rubber has low absorption of water.Keywords: clayey soil, MSWIFA, proctor test, rubber
Procedia PDF Downloads 11817555 Transition Economies, Typology, and Models: The Case of Libya
Authors: Abderahman Efhialelbum
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The period since the fall of the Berlin Wall on November 9, 1989, and the collapse of the former Soviet Union in December 1985 has seen a major change in the economies and labour markets of Eastern Europe. The events also had reverberating effects across Asia and South America and parts of Africa, including Libya. This article examines the typologies and the models of transition economies. Also, it sheds light on the Libyan transition in particular and the impact of Qadhafi’s regime on the transition process. Finally, it illustrates how the Libyan transition process followed the trajectory of other countries using economic indicators such as free trade, property rights, and inflation.Keywords: transition, economy, typology, model, Libya
Procedia PDF Downloads 15717554 Influence of Surface Fault Rupture on Dynamic Behavior of Cantilever Retaining Wall: A Numerical Study
Authors: Partha Sarathi Nayek, Abhiparna Dasgupta, Maheshreddy Gade
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Earth retaining structure plays a vital role in stabilizing unstable road cuts and slopes in the mountainous region. The retaining structures located in seismically active regions like the Himalayas may experience moderate to severe earthquakes. An earthquake produces two kinds of ground motion: permanent quasi-static displacement (fault rapture) on the fault rupture plane and transient vibration, traveling a long distance. There has been extensive research work to understand the dynamic behavior of retaining structures subjected to transient ground motions. However, understanding the effect caused by fault rapture phenomena on retaining structures is limited. The presence of shallow crustal active faults and natural slopes in the Himalayan region further highlights the need to study the response of retaining structures subjected to fault rupture phenomena. In this paper, an attempt has been made to understand the dynamic response of the cantilever retaining wall subjected to surface fault rupture. For this purpose, a 2D finite element model consists of a retaining wall, backfill and foundation have been developed using Abaqus 6.14 software. The backfill and foundation material are modeled as per the Mohr-Coulomb failure criterion, and the wall is modeled as linear elastic. In this present study, the interaction between backfill and wall is modeled as ‘surface-surface contact.’ The entire simulation process is divided into three steps, i.e., the initial step, gravity load step, fault rupture step. The interaction property between wall and soil and fixed boundary condition to all the boundary elements are applied in the initial step. In the next step, gravity load is applied, and the boundary elements are allowed to move in the vertical direction to incorporate the settlement of soil due to the gravity load. In the final step, surface fault rupture has been applied to the wall-backfill system. For this purpose, the foundation is divided into two blocks, namely, the hanging wall block and the footwall block. A finite fault rupture displacement is applied to the hanging wall part while the footwall bottom boundary is kept as fixed. Initially, a numerical analysis is performed considering the reverse fault mechanism with a dip angle of 45°. The simulated result is presented in terms of contour maps of permanent displacements of the wall-backfill system. These maps highlighted that surface fault rupture can induce permanent displacement in both horizontal and vertical directions, which can significantly influence the dynamic behavior of the wall-backfill system. Further, the influence of fault mechanism, dip angle, and surface fault rupture position is also investigated in this work.Keywords: surface fault rupture, retaining wall, dynamic response, finite element analysis
Procedia PDF Downloads 10617553 Investigation of Airship Motion Sensitivity to Geometric Parameters
Authors: Han Ding, Wang Xiaoliang, Duan Dengping
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During the process of airship design, the layout and the geometric shape of the hull and fins are crucial to the motion characteristics of the airship. In this paper, we obtained the quantification motion sensitivity of the airship to geometric parameters through turning circles and horizontal/vertical zigzag maneuvers by the parameterization of airship shape and building the dynamic model using Lagrangian approach and MATLAB Simulink program. In the dynamics simulation program, the affection of geometric parameters to the mass, center of gravity, moments of inertia, product of inertia, added mass and the aerodynamic forces and moments have been considered.Keywords: airship, Lagrangian approach, turning circles, horizontal/vertical zigzag maneuvers
Procedia PDF Downloads 42517552 Hybrid Seismic Energy Dissipation Devices Made of Viscoelastic Pad and Steel Plate
Authors: Jinkoo Kim, Minsung Kim
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This study develops a hybrid seismic energy dissipation device composed of a viscoelastic damper and a steel slit damper connected in parallel. A cyclic loading test is conducted on a test specimen to validate the seismic performance of the hybrid damper. Then a moment-framed model structure is designed without seismic load so that it is retrofitted with the hybrid dampers. The model structure is transformed into an equivalent simplified system to find out optimum story-wise damper distribution pattern using genetic algorithm. The effectiveness of the hybrid damper is investigated by fragility analysis and the life cycle cost evaluation of the structure with and without the dampers. The analysis results show that the model structure has reduced probability of reaching damage states, especially the complete damage state, after seismic retrofit. The expected damage cost and consequently the life cycle cost of the retrofitted structure turn out to be significantly small compared with those of the original structure. Acknowledgement: This research was supported by the Ministry of Trade, Industry and Energy (MOTIE) and Korea Institute for Advancement of Technology (KIAT) through the International Cooperative R & D program (N043100016).Keywords: seismic retrofit, slit dampers, friction dampers, hybrid dampers
Procedia PDF Downloads 28317551 Gravitational Energy Storage by Using Concrete Stacks
Authors: Anusit Punsirichaiyakul, Tosaphol Ratniyomchai, Thanatchai Kulworawanichpong
Abstract:
The paper aims to study the energy storage system in the form of gravity energy by the weight of concrete stacks. This technology has the potential to replace expensive battery storage. This paper is a trial plan in abandoned mines in Thailand. This is to start with construct concrete boxes to be stacked vertically or obliquely to form appropriate shapes and, therefore, to store the potential energy. The stored energy can be released or discharged back to the system by deploying the concrete stacks to the ground. This is to convert the potential energy stored in the concrete stacks to the kinetic energy of the concrete box movement. This design is incorporating mechanical transmission to reduce the height of the concrete stacks. This study also makes a comparison between the energy used to construct concrete stacks in various shapes and the energy to deploy all the concrete boxes to ground. This paper consists of 2 test systems. The first test is to stack the concrete in vertical shape. The concrete stack has a maximum height of 50 m with a gear ratio of 1:200. The concrete box weight is 115 tons/piece with a total stored energy of 1800 kWh. The oblique system has a height of 50 m with a similar gear ratio of 1:200. The weight of the concrete box is 90 tons/piece and has a total stored energy of 1440 kWh. Also, it has an overall efficiency of 65% and a lifetime of 50 years. This storage has higher storage densities compared to other systems.Keywords: gravity, concrete stacks, vertical, oblique
Procedia PDF Downloads 165