Search results for: automated power system

Authors: E. Hegazy, S. Anderberg, J. Krook

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The city's wire-based infrastructure systems (WBIS) are responsible for the delivery of electricity, telecommunications, sanitation, drainage, and district heating and are a necessity for sustainable modern urban life. Maintaining the functionality of these structures involves high costs and, brings disturbance to the local community and effects on the environment. One key reason for this is that the cables and pipes are placed under streets, making system parts easily worn and their service lifetime reduced, and all maintenance and renewal rely on recurrent needs for excavation. In Sweden, a significant part of wire-based infrastructure is already outdated and will need to be replaced in the coming decades. The replacement of these systems will entail massive costs as well as important traffic disruption and environmental disturbance. However, this challenge may also open a unique opportunity to introduce new, more sustainable technologies and management practices. The transformation of WBIS management for long-term sustainability and meeting maintenance and renewal needs does not have a comprehensive approach. However, a systemic approach may inform WBIS management. This approach considers both technical and non-technical aspects, as well as time-related factors. Nevertheless, there is limited systemic knowledge of how different factors influence current management practices. The aim of this study is to address this knowledge gap and contribute to the understanding of what factors influence the current practice of WBIS management. A case study approach is used to identify current management practices, the underlying factors that influence them, and their implications for sustainability outcomes. The case study is based on both quantitative data on the local system and data from interviews and workshops with local practitioners and other stakeholders. Linköping was selected as a case since it provided good accessibility to the water administration and relevant data for analyzing water infrastructure management strategies. It is a sufficiently important city in Sweden to be able to identify challenges, which, to some extent, are common to all Swedish cities. By uncovering current practices and what is influencing Linköping, knowledge gaps and uncertainties related to sustainability consequences were highlighted. The findings show that goals, priorities, and policies controlling management are short-termed, and decisions on maintenance and renewal are often restricted to finding solutions to the most urgent issues. Sustainability transformation in the infrastructure area will not be possible through individual efforts without coordinated technical, organizational, business, and regulatory changes.

Keywords: case study, infrastructure, management, practice, Sweden

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Authors: Jun-ichi Ochiai, Itsuki Noda, Ryo Kanamori, Keiji Hirata, Hitoshi Matsubara, Hideyuki Nakashima

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We conducted exhaustive simulations for data assimilation and evaluation of service quality for various setting in a new shared transportation system, called SAVS. Computational social simulation is a key technology to design recent social services like SAVS as new transportation service. One open issue in SAVS was to determine the service scale through the social simulation. Using our exhaustive simulation framework, OACIS, we did data-assimilation and evaluation of effects of SAVS based on actual tax-use data at Tajimi city, Japan. Finally, we get the conditions to realize the new service in a reasonable service quality.

Keywords: on-demand bus sytem, social simulation, data assimilation, exhaustive simulation

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Authors: R. S. Malik, S. K. Madan, V. K. Sehgal

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Reinforced concrete (RCC) buildings with dual system consisting of shear walls and moment resisting frames or braces and moment resisting frames have been widely used to resist lateral forces during earthquakes. The two dual systems are designed to resist the total design lateral force in proportion to their lateral stiffness. The response of the combination of braces and shear walls has not yet been studied therefore has practically no work to refer to. The combination may prove to be more effective in lateral load resistance by employing the peculiar advantages of shear walls and braces simultaneously and may also improve the architectural appearance of structures. This concept has been applied to regular RCC buildings provided with shear walls, braces, and their combinations.

Keywords: dynamic analysis, displacement, pushover analysis, dual structures, storey drift

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Authors: Hromada Martin

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Risk analysis is considered as a fundamental aspect relevant for ensuring the level of critical infrastructure protection, where the critical infrastructure is seen as system, asset or its part which is important for maintaining the vital societal functions. Article actually discusses and analyzes the potential application of selected tools of information support for the implementation and within the framework of risk analysis and critical infrastructure protection. Use of the information in relation to their risk analysis can be viewed as a form of simplifying the analytical process. It is clear that these instruments (information support) for these purposes are countless, so they were selected representatives who have already been applied in the selected area of critical infrastructure, or they can be used. All presented fact were the basis for critical infrastructure resilience evaluation methodology development.

Keywords: critical infrastructure, protection, resilience, risk analysis

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Authors: Aurélia Jandot

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With the oil and economic crises which began in the 1970’s, it has progressively appeared necessary to convince the French “general public“ that a use of new energy sources was essential. In this field, nuclear energy represented the future and concentrated lots of hopes. However, the discourse about nuclear energy has progressively seen negative arguments growing in the French media. The gradual changes in the perception of nuclear energy will be studied here through the arguments given in the main French weekly newsmagazines, which had a great impact on the readers, thus on the “general public“, from the 1970’s to the end of the 1980’s. Indeed, to understand better these changes will be taken into account the major international events, the reorientations of the French domestic policy, and the evolutions of the nuclear technology. As this represents a considerable amount of copies and thus of information, will be selected here the main articles which emphasize the “mental images“ aiming to direct the thought of the readers, and which have led the public awareness and acceptance to evolve. From the 1970’s to the end of the 1980’s, two dichotomous trends are in confrontation : one is promoting the perception of the nuclear energy, the other is discrediting it. Moreover, these two trends are organized in two axes. The first axis is about the engineerings evolutions, such as the main French media represent them, with its approximations, its exaggerations, its fictions sometimes. Is added the will to make accessible to the “general public“ some concepts which are quite difficult to understand for the largest number. The second axis rests on the way the major accidents of the period are approached, including those of Three Mile Island and Chernobyl. Thanks to these accidents and because of the international relations evolutions, the ecologist movements and their impacts have progressively grown, with evident consequences on the public perception of nuclear energy and on the way the successive governments can implement new power plants in France. Then, in both cases, over the period considered, the language has changed, as the perceptible objectives of the communication, allowing to discern the deepest intentions of the newsmagazines editing. This is all these changes that will be emphasized, over a period where the nuclear energy technology, to there a field for specialists, bearing mystery and secret, has become a social issue seemingly open to all.

Keywords: social issues, public acceptance, mediatization, discourse changes

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Authors: Antoine Lauvray, Fabien Poulhaon, Pierre Michaud, Pierre Joyot, Emmanuel Duc

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Additive Friction Stir Manufacturing (AFSM) is a new industrial process that follows the emergence of friction-based processes. The AFSM process is a solid-state additive process using the energy produced by the friction at the interface between a rotating non-consumable tool and a substrate. Friction depends on various parameters like axial force, rotation speed or friction coefficient. The feeder material is a metallic rod that flows through a hole in the tool. Unlike in Friction Stir Welding (FSW) where abundant literature exists and addresses many aspects going from process implementation to characterization and modeling, there are still few research works focusing on AFSM. Therefore, there is still a lack of understanding of the physical phenomena taking place during the process. This research work aims at a better AFSM process understanding and implementation, thanks to numerical simulation and experimental validation performed on a prototype effector. Such an approach is considered a promising way for studying the influence of the process parameters and to finally identify a process window that seems relevant. The deposition of material through the AFSM process takes place in several phases. In chronological order these phases are the docking phase, the dwell time phase, the deposition phase, and the removal phase. The present work focuses on the dwell time phase that enables the temperature rise of the system composed of the tool, the filler material, and the substrate and due to pure friction. Analytic modeling of heat generation based on friction considers as main parameters the rotational speed and the contact pressure. Another parameter considered influential is the friction coefficient assumed to be variable due to the self-lubrication of the system with the rise in temperature or the materials in contact roughness smoothing over time. This study proposes, through numerical modeling followed by experimental validation, to question the influence of the various input parameters on the dwell time phase. Rotation speed, temperature, spindle torque, and axial force are the main monitored parameters during experimentations and serve as reference data for the calibration of the numerical model. This research shows that the geometry of the tool as well as fluctuations of the input parameters like axial force and rotational speed are very influential on the temperature reached and/or the time required to reach the targeted temperature. The main outcome is the prediction of a process window which is a key result for a more efficient process implementation.

Keywords: numerical model, additive manufacturing, friction, process

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Authors: Abdel-Monem Sayed Mohamed

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Lake Aswan is one of the largest man-made reservoirs in the world. The reservoir began to fill in 1964 and the level rose gradually, with annual irrigation cycles, until it reached a maximum water level of 181.5 m in November 1999, with a capacity of 160 km3. The filling of such large reservoir changes the stress system either through increasing vertical compressional stress by loading and/or increased pore pressure through the decrease of the effective normal stress. The resulted effect on fault zones changes stability depending strongly on the orientation of pre-existing stress and geometry of the reservoir/fault system. The main earthquake occurred on November 14, 1981, with magnitude 5.5. This event occurred after 17 years of the reservoir began to fill, along the active part of the Kalabsha fault and located not far from the High Dam. Numerous of small earthquakes follow this earthquake and continue till now. For this reason, 13 seismograph stations (radio-telemetry network short-period seismometers) were installed around the northern part of Lake Aswan. The main purpose of the network is to monitor the earthquake activity continuously within Aswan region. The data described here are obtained from the continuous record of earthquake activity and lake-water level variation through the period from 1982 to 2015. The seismicity is concentrated in the Kalabsha area, where there is an intersection of the easterly trending Kalabsha fault with the northerly trending faults. The earthquake foci are distributed in two seismic zones, shallow and deep in the crust. Shallow events have focal depths of less than 12 km while deep events extend from 12 to 28 km. Correlation between the seismicity and the water level variation in the lake provides great suggestion to distinguish the micro-earthquakes, particularly, those in shallow seismic zone in the reservoir–triggered seismicity category. The water loading is one factor from several factors, as an activating medium in triggering earthquakes. The common factors for all cases of induced seismicity seem to be the presence of specific geological conditions, the tectonic setting and water loading. The role of the water loading is as a supplementary source of earthquake events. So, the earthquake activity in the area originated tectonically (ML ≥ 4) and the water factor works as an activating medium in triggering small earthquakes (ML ≤ 3). Study of the inducing seismicity from the water level variation in Aswan Lake is of great importance and play great roles necessity for the safety of the High Dam body and its economic resources.

Keywords: Aswan lake, Aswan seismic network, seismicity, water level variation

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Authors: Marcelo T. Okano, Oduvaldo Vendrametto, Osmildo S. Santos, Marcelo E. Fernandes, Heide Landi

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Teaching of entrepreneurship and innovation in Brazilian universities has increased in recent years due to several factors such as the emergence of disciplines like biotechnology increased globalization reduced basic funding and new perspectives on the role of the university in the system of knowledge production Innovation is increasingly seen as an evolutionary process that involves different institutional spheres or sectors in society Entrepreneurship is a milestone on the road towards economic progress, and makes a huge contribution towards the quality and future hopes of a sector, economy or even a country. Entrepreneurship is as important in small and medium-sized enterprises (SMEs) and local markets as in large companies, and national and international markets, and is just as key a consideration for public companies as or private organizations. Entrepreneurship helps to encourage the competition in the current environment that leads to the effects of globalization. There is an increasing tendency for government policy to promote entrepreneurship for its apparent economic benefit. Accordingly, governments seek to employ entrepreneurship education as a means to stimulate increased levels of economic activity. Entrepreneurship education and training (EET) is growing rapidly in universities and colleges throughout the world, and governments are supporting it both directly and through funding major investments in advice-provision to would-be entrepreneurs and existing small businesses. The Triple Helix of university–industry–government relations is compared with alternative models for explaining the current research system in its social contexts. Communications and negotiations between institutional partners generate an overlay that increasingly reorganizes the underlying arrangements. To achieve the objective of this research was a survey of the literature on the entrepreneurship and innovation and then a field research with 100 students of Fatec. To collect the data needed for analysis, we used the exploratory research of a qualitative nature. We asked to respondents what degree of knowledge over ten related to entrepreneurship and innovation topics, responses were answered in a Likert scale with 4 levels, none, small, medium and large. We can conclude that the terms such as entrepreneurship and innovation are known by most students because the university propagates them across disciplines, lectures, and institutes innovation. The more specific items such as canvas and Design thinking model are unknown by most respondents. The importance of the University in teaching innovation and entrepreneurship in the transmission of this knowledge to the students in order to equalize the knowledge. As a future project, these items will be re-evaluated to create indicators for measuring the knowledge level.

Keywords: Brazilian universities, entrepreneurship, innovation, entrepreneurship, globalization

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Authors: May Al Sahib

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This paper draws together an analysis of two autobiographical writings; Ahdaf Soueif’s Cairo: My City, Our Revolution (2012), Radwa Ashour’s Heavier than Radwa (2013), and Revolution is My Name: An Egyptian Woman’s Diary from Eighteen Days in Tahrir (2015). Soueif, Ashour, and Prince are Egyptian authors, activists, and cultural commentators who are fully aware that being a ‘third world’ citizen constrains the writer into taking a specific pattern in writing. However, this paper will analyze the choice of literary form in writing the 2011 January revolution. All texts give factual accounts of the revolution with all its contesting powers lingering with mixed references of anxiety and merriment that accentuates their sense of communal solidarity against social corruption and political positioning. Through shifting between the pronouns ‘I’ and ‘we’, these narratives do not solely engage with the personal life of the memorialist; but rather give an account of the collective. Both writers take us to the heart of high-spirited Tahrir Square in 2011 while millions are ranting to oust Hosni Mubarak, the 30 years ruling dictator. By utilizing the instrumentality of collective memory for expressing textual collectivity in their non-fictional writings, these writers are depicting the people power of Egyptians and the historical civil-resistance against governmental unfairness and establishing a certain type of patriotism that elevates and priorities itself from minor conflicts. Their de-individualizing type of life narrative represents the Arabic nation through vital socio-political situations that perpetuate the politics of resistance and collectivity with a constant fear of betraying it and erupts historical moments aiming for an improved future. The texts incorporate an explicit set of reported political series of thought that shape an overall public argument and representational ideas.

Keywords: resistance narrative, life-writing, Tahrir memoir, Middle Eastern literature

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Authors: Ramon Erasmo Verdin Rodriguez

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Many has been the ways that historically the managers and gurus has been trying to get closer to the perfect supply chain, but since this topic is so vast and very complex the bigger the companies are, the duty has not been certainly easy. On this research, you are going to see thru the entrails of the logistics that happens at a glass manufacturing company with the number one raw material of the process that is the silica sand. After a very quick passage thru the supply chain, this document is going to focus on the way that raw materials flow thru the system, so after that, an analysis and research can take place to improve the logistics. Thru Operations Research techniques, it will be analyzed the current scheme of distribution and inventories of raw materials at a glass company’s plants, so after a mathematical conceptualization process, the supply chain could be optimized with the purpose of reducing the uncertainty of supply and obtaining an economic benefit at the very end of this research.

Keywords: inventory management, operations research, optimization, supply chain

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Authors: Lema Catherine Forje

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Innovation activates the system of an economy to a new level. Innovation follows a process. The first step in innovation is the idea-generation process. There is widespread appreciation that people go to great lengths, incur expenses: energy and materials to generate innovative ideas. People get inspired, create, and connect. The inspiration also enables the building of a culture of innovation. Data collection was done through a face-to-face interview with the producer of the first Cameroon beer that came out in the early 1960s, a rice producing company, a cement producing company, and 100 women following a type of dressing commonly worn by Cameroonian women (wrappa). There were a total number of one hundred and three interviewees. The implication of this study is for everybody. It sheds light on the factors that are likely to sustain an innovation. Conclusion emphasises continuous research to keep giving the innovation a face lift.

Keywords: entrepreneurship, ideas, innovation, sustainability

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Authors: Vishnu Pratap Singh Kirar

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The main aim of the communication system is to achieve maximum performance. In cognitive radio, any user or transceiver have the ability to sense best suitable channel, while the channel is not in use. It means an unlicensed user can share the spectrum of licensed user without any interference. Though the spectrum sensing consumes a large amount of energy and it can reduce by applying various artificial intelligent methods for determining proper spectrum holes. It also increases the efficiency of Cognitive Radio Network (CRN). In this survey paper, we discuss the use of different learning models and implementation of Artificial Neural Network (ANN) to increase the learning and decision-making capacity of CRN without affecting bandwidth, cost and signal rate.

Keywords: artificial neural network, cognitive radio, cognitive radio networks, back propagation, spectrum sensing

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Authors: Rhommel Grutas, Ishmael Narag, Harley Lacbawan

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Construction of high-rise buildings is a means to address the increasing population in Metro Manila, Philippines. The existence of the Valley Fault System within the metropolis and other nearby active faults poses threats to a densely populated city. The distant, shallow and large magnitude earthquakes have the potential to generate slow and long-period vibrations that would affect medium-to-high rise buildings. Heavy damage and building collapse are consequences of prolonged shaking of the structure. If the ground and the building have almost the same period, there would be a resonance effect which would cause the prolonged shaking of the building. Microzoning the long-period ground response would aid in the seismic design of medium to high-rise structures. The shear-wave velocity structure of the subsurface is an important parameter in order to evaluate ground response. Borehole drilling is one of the conventional methods of determining shear-wave velocity structure however, it is an expensive approach. As an alternative geophysical exploration, microtremor array measurements can be used to infer the structure of the subsurface. Microtremor array measurement system was used to survey fifty sites around Metro Manila including some municipalities of Rizal and Cavite. Measurements were carried out during the day under good weather conditions. The team was composed of six persons for the deployment and simultaneous recording of the microtremor array sensors. The instruments were laid down on the ground away from sewage systems and leveled using the adjustment legs and bubble level. A total of four sensors were deployed for each site, three at the vertices of an equilateral triangle with one sensor at the centre. The circular arrays were set up with a maximum side length of approximately four kilometers and the shortest side length for the smallest array is approximately at 700 meters. Each recording lasted twenty to sixty minutes. From the recorded data, f-k analysis was applied to obtain phase velocity curves. Inversion technique is applied to construct the shear-wave velocity structure. This project provided a microzonation map of the metropolis and a profile showing the long-period response of the deep sedimentary basin underlying Metro Manila which would be suitable for local administrators in their land use planning and earthquake resistant design of medium to high-rise buildings.

Keywords: earthquake, ground motion, microtremor, seismic microzonation

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Authors: Saleh Hayat

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Efficiency, productivity and sustainability are important factors for structure and the application of processes in green building. Various previous studies have addressed efficiency, productivity and sustainability separately. This research study aims to investigate the implications of these three factors taking together. Frequency analysis and the ranking techniques are carried out to explore the connection between these factors. The interconnection matrix has been developed and functional grouping is made based upon data from expert opinion and field professionals. The existence of a relationship, the type of relationship and the scaled impact have been drawn. Additionally, a system diagram has been developed to show the variable correlation. The results of expert opinion show that efficiency, productivity and sustainability have a stronger impact on green buildings.

Keywords: efficiency, green building, productivity, sustainability

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Authors: Hanizam Awang, Mohammed Zuhear Al-Mulali

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In this study, the possibility of using unground oil palm ash (UOPA) for producing foamed concrete is investigated. The UOPA used in this study is produced by incinerating palm oil biomass at a temperature exceeding 1000ºC. A semi-structural density of 1300kg/m3 was used with filler to binder ratio of 1.5 and preliminary water to binder ratio of 0.45. Cement was replaced by UOPA at replacement levels of 0, 25, 35, 45, 55 and 65% by weight of binder. Properties such as density, compressive strength, drying shrinkage and water absorption were investigated to the age of 90 days. The mix with a 35% of UOPA content was chosen to be used as the base material of a newly designed interlocking, mortar-less block system.

Keywords: foamed concrete, oil palm ash, strength, interlocking block

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Authors: Mohammed Hussein, Abualseoud Hanani

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In Low Earth Orbit (LEO) satellite constellation system, routing data from the source all the way to the destination constitutes a daunting challenge because LEO satellite constellation resources are spare and the high speed movement of LEO satellites results in a highly dynamic network topology. This situation limits the applicability of traditional routing approaches that rely on exchanging topology information upon change or setup of a connection. Consequently, in recent years, many routing algorithms and implementation strategies for satellite constellation networks with Inter Satellite Links (ISLs) have been proposed. In this article, we summarize and classify some of the most representative solutions according to their objectives, and discuss their advantages and disadvantages. Finally, with a look into the future, we present some of the new challenges and opportunities for LEO satellite constellations in general and routing protocols in particular.

Keywords: LEO satellite constellations, dynamic topology, IP routing, inter-satellite-links

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Authors: Jade Martínez-Llinàs, Pere Colet

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By exploring the possible dynamical regimes in a prototypical model for mutually delay-coupled OEOs, here it is shown that two mutually coupled non-identical OEOs, besides in- and out-of-phase square-waves, can generate stable square-wave pulses synchronized at a quarter of the period (T/4) in a broad parameter region. The key point to obtain T/4 solutions is that the two OEO operate with mixed feedback, namely with negative feedback in one and positive in the other. Furthermore, the coexistence of multiple solutions provides a large degree of flexibility for tuning the frequency in the GHz range without changing any parameter. As a result the two coupled OEOs system is good candidate to be implemented for information encoding as a high-capacity memory device.

Keywords: nonlinear optics, optoelectronic oscillators, square waves, synchronization

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Authors: Bo Yang, Christopher Monterola

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Urban intersection control without the use of the traffic light has the potential to vastly improve the efficiency of the urban traffic flow. For most proposals in the literature, such lightless intersection control depends on the mass market commercialization of highly intelligent autonomous vehicles (AV), which limits the prospects of near future implementation. We present an efficient lightless intersection traffic control scheme that only requires Level 1 AV as defined by NHTSA. The technological barriers of such lightless intersection control are thus very low. Our algorithm can also accommodate a mixture of AVs and conventional vehicles. We also carry out large scale numerical analysis to illustrate the feasibility, safety and robustness, comfort level, and control efficiency of our intersection control scheme.

Keywords: intersection control, autonomous vehicles, traffic modelling, intelligent transport system

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Authors: Denise Muro

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Conflict in Syria, producing over 11 million displaced persons, has incited global attention to displacement. Although neighboring countries have borne the largest part of the displacement burden, due to the influx of refugees into Europe, the so-called ‘refugee crisis’ is taking place on two fronts: Syria’s neighboring countries, with millions of refugees, and Europe, a destination goal for so many that European states face unprecedented challenges. With increasing attention to displacement, forcibly displaced persons are consistently portrayed as either un-agentic victims, or as dangerous free agents. Recognizing that these dominant portrayals involve discourses of power and inequality, this research investigates the extent to which this victim-agent dichotomy affects refugees and organizations that work closely with them during initial integration processes in Berlin, Germany. The research measures initial integration based on German policy measures regarding integration juxtaposed with the way refugees and those who work with them understand integration. Additionally, the study examines day-to-day interactions of refugees in Germany as a way to gauge social integration in a bottom-up approach. This study involved a discourse analysis of portrayals of refugees and participant observation and interviews with refugees and those who work closely with them, which took place during fieldwork in Berlin in the summer of 2016. Germany is unique regarding their migration history and lack of successful integration, in part due to the persistent refrain, ‘Wir sind kein einwanderungsland’ (‘We are not an immigration country’). Still, their accepted asylum seeker population has grown exponentially in the past few years. Findings suggest that the victim-agent dichotomy is present and impactful in the process of refugees entering and integrating into Germany. Integration is hindered due to refugees either being patronized or criminalized to such an extent that, despite being constantly told that they must integrate, they cannot become part of German society.

Keywords: discourse analysis, Germany, integration, refugee crisis

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Authors: Reza Mohammadi

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Using quartic spline, we develop a method for numerical solution of singularly perturbed two-point boundary-value problems. The purposed method is fourth-order accurate and applicable to problems both in singular and non-singular cases. The convergence analysis of the method is given. The resulting linear system of equations has been solved by using a tri-diagonal solver. We applied the presented method to test problems which have been solved by other existing methods in references, for comparison of presented method with the existing methods. Numerical results are given to illustrate the efficiency of our methods.

Keywords: second-order ordinary differential equation, singularly-perturbed, quartic spline, convergence analysis

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Authors: O. Hanita, S. A. Ainnul Hamidah, A. H. Yang Zalila, M. R. Siti Nadiah, M. H. Najihah, M. A. Hapipah

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The crude extract of the leaves of Actinodaphne sesquipedalis Hook. F. Var. Glabra (Kochummen), was taken under phytochemical investigation. The crude methanolic extract was partitioned with a different solvent system by increasing their polarities (n-hexane, dichloromethane, and methanol). The compounds were fractionated and isolated from n-hexane partition by using column chromatography with silica gel 60 or Sephadex LH-20 as a stationary phase and preparative thin layer chromatographic technique. Isolates were characterized using TLC, FTIR, UV spectrophotometer and NMR spectroscopy. The n-hexane fractionates yielded a total of four compounds namely N-methyllaurotetanine (1), dicentrine (2), β-sitosterol (3), and stigmasterol (4). The result indicates that the leaves of Actinodaphne sesquipedalis may provide a rich source of alkaloids and triterpenoids.

Keywords: actinodaphne sesquipedalis, alkaloids, phytochemical investigation, triterpenoids

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Authors: Kious Mecheri, Hadjadj Abdechafik, Ameur Aissa

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The wear of cutting tool degrades the quality of the product in the manufacturing processes. The online monitoring of the cutting tool wear level is very necessary to prevent the deterioration of the quality of machining. Unfortunately there is not a direct manner to measure the cutting tool wear online. Consequently we must adopt an indirect method where wear will be estimated from the measurement of one or more physical parameters appearing during the machining process such as the cutting force, the vibrations, or the acoustic emission etc. In this work, a neural network system is elaborated in order to estimate the flank wear from the cutting force measurement and the cutting conditions.

Keywords: flank wear, cutting forces, high speed milling, signal processing, neural network

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Authors: Hitalo Silva

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The most famous corruption scandals in the past four years were taken in Latin America, especially in Brazil, but besides the stain that these countries suffered in an international field, there was a huge effort to create or modernize its national anti-corruption laws. Also, the countries are implementing new standards for investigations and corporate compliance programs, in order to combat corruption and prevent the money laundering. But here is the following question: is here an invisible uniformization/transnationalization of the anti-corruption systems in Latin America? This new scenario reflects the impacts of the corruption investigations conducted in Latin America countries, such as Car Wash Operation in Brazil, Pretelt Case in Colombia, Gasoducto Sur Peruano case and the Mr. Alex Kouri’s case both in Peru. Legal and institutional pro-transparency reforms were made recently, the companies are trying to implement new standards of conduct and investing in their compliance department. In this sense, there is a huge homogeneity in Latin America concerning the structuring of corporate compliance programs, a truly transnationalization not only of laws but also corporate standards among these countries. Although legislative initiatives vary among the countries, there is a tendency to impose rigid liability standards for the companies being investigated for corruption, not only the personal punishments of their executives, which demonstrate the power of authorities to strength the investigative tools. Also, instruments such as leniency agreements and plea bargain are essential to put a central role in enforcement activities in Latin America. In other words, in a region where six former Presidents were convicted for acts of corruption, and, companies such as Odebrecht that is accused of offering bribes to politicians from Argentina to México, passing through Ecuador, Colombia, Guatemala and Panama, this demonstrates the necessity to increase strength of their legal framework in a sense that unify transnational goals. All things considered, this paper will show how anti-corruption regulators are cooperating in Latin America jurisdictions in order to unify their laws and how the private sector is dealing with this new scenario of corporate culture change.

Keywords: compliance, corruption, investigations, Latin America, transnational

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Authors: N. Kazantseva, P. Krakhmalev, I. Yadroitsev, A. Fefelov, N. Vinogradova, I. Ezhov, T. Kurennykh

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Martensitic texture-phase transition in Selective Laser Melting (SLM) Ti-6Al-4V (ELI) alloys was found. Electron Backscatter Diffraction (EBSD) analysis showed the initial cubic beta < 100 > (001) BCC texture. Such kind of texture is observed in BCC metals with flat rolling texture when axis is in the direction of rolling and the texture plane coincides with the plane of rolling. It was found that the texture of the parent BCC beta-phase determined the texture of low-temperature HCP alpha-phase limited the choice of its orientation variants. The {10-12} < -1011 > twinning system in titanium alloys after SLM was determined. Analysis of the oxygen contamination in SLM alloys was done. Comparison of the obtained results with the conventional titanium alloys is also provided.

Keywords: additive technology, texture, twins, Ti-6Al-4V, oxygen content

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Authors: Pedro Paulino

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The majority of the world’s population is already living in urban areas and the urban population is expected to keep increasing in the next decades. This exponential increase in urban population carries with it obvious mobility problems. Not only a new paradigm in the transport sector is needed in order to address these problems; effective regulatory policies to ensure the quality of services, passenger rights, competition between operators and consistency of the entire mobile ecosystem are needed as well. The purpose of this paper is to present the problems the world faces in this sector and contribute to their solution. Indeed, our study concludes that only through the active supervision of the markets and the activity of monitoring the various operators will it be possible to develop a sustainable and efficient transport system which meets the needs of a changing world.

Keywords: mobility, regulation policies, sanctioning powers, sustainable transport

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Authors: Jun Young Moon, Hyeonggeon Lee, Jong Tae Kim

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In this paper, we present Cortex-M3 based virtual platform which can virtualize wearable hardware platform and evaluate hardware performance. Cortex-M3 is very popular microcontroller in wearable devices, hardware sensors and display devices. This platform can be used to implement software layer for specific hardware architecture. By using the proposed platform the software development process can be parallelized with hardware development process. We present internal mechanism to implement the proposed virtual platform and describe how to use the proposed platform to develop software by using case study which is low cost wearable device that uses Cortex-M3.

Keywords: electronic system level design, software development, virtual platform, wearable device

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Authors: Jasbir Singh Gill, Baljit Singh

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Scheduling and mapping the application task graph on multiprocessor parallel systems is considered as the most crucial and critical NP-complete problem. Many genetic algorithms have been proposed to solve such problems. In this paper, two genetic approach based algorithms have been designed and developed with or without task duplication. The proposed algorithms work on two fitness functions. The first fitness i.e. task fitness is used to minimize the total finish time of the schedule (schedule length) while the second fitness function i.e. process fitness is concerned with allocating the tasks to the available highly efficient processor from the list of available processors (load balance). Proposed genetic-based algorithms have been experimentally implemented and evaluated with other state-of-art popular and widely used algorithms.

Keywords: parallel computing, task scheduling, task duplication, genetic algorithm

Procedia PDF Downloads 331

Authors: Jerzy F. Janik, Mariusz Drygas, Miroslaw M. Bucko

Abstract:

A simple precursor system has been recently developed in our laboratory for the conversion of affordable microcrystalline gallium antimonide GaSb to a range of nanocrystalline powders of gallium nitride GaN – a wide bandgap semiconductor indispensable in modern optoelectronics. The process relies on high temperature nitridation reactions of GaSb with ammonia. Topochemical relationships set up by the cubic lattice of GaSb result in some metastable cubic GaN formed in addition to the stable hexagonal GaN. A prior application of high energy ball milling to the initially microcrystalline GaSb precursor is shown to alter the nitridation output.

Keywords: nanocrystalline, gallium nitride, GaN, gallium antimonide, GaSb, nitridation, ball milling

Procedia PDF Downloads 385

Authors: Gamaliel Salazar, Adriana Chazaro, Oscar Madrigal

Abstract:

The evolution of Unmanned Aerial Systems (UAS) has made it possible to develop new vehicles capable to perform microgravity experiments which due its cost and complexity were beyond the reach for many institutions. In this study, the aerodynamic behavior of an UAS is studied through its deceleration stage after an initial free fall phase (where the microgravity effect is generated) using Computational Fluid Dynamics (CFD). Due to the fact that the payload would be analyzed under a microgravity environment and the nature of the payload itself, the speed of the UAS must be reduced in a smoothly way. Moreover, the terminal speed of the vehicle should be low enough to preserve the integrity of the payload and vehicle during the landing stage. The UAS model is made by a study pod, control surfaces with fixed and mobile sections, landing gear and two semicircular wing sections. The speed of the vehicle is decreased by increasing the angle of attack (AoA) of each wing section from 2° (where the airfoil S1091 has its greatest aerodynamic efficiency) to 80°, creating a circular wing geometry. Drag coefficients (Cd) and forces (Fd) are obtained employing CFD analysis. A simplified 3D model of the vehicle is analyzed using Ansys Workbench 16. The distance between the object of study and the walls of the control volume is eight times the length of the vehicle. The domain is discretized using an unstructured mesh based on tetrahedral elements. The refinement of the mesh is made by defining an element size of 0.004 m in the wing and control surfaces in order to figure out the fluid behavior in the most important zones, as well as accurate approximations of the Cd. The turbulent model k-epsilon is selected to solve the governing equations of the fluids while a couple of monitors are placed in both wing and all-body vehicle to visualize the variation of the coefficients along the simulation process. Employing a statistical approximation response surface methodology the case of study is parametrized considering the AoA of the wing as the input parameter and Cd and Fd as output parameters. Based on a Central Composite Design (CCD), the Design Points (DP) are generated so the Cd and Fd for each DP could be estimated. Applying a 2nd degree polynomial approximation the drag coefficients for every AoA were determined. Using this values, the terminal speed at each position is calculated considering a specific Cd. Additionally, the distance required to reach the terminal velocity at each AoA is calculated, so the minimum distance for the entire deceleration stage without comprising the payload could be determine. The Cd max of the vehicle is 1.18, so its maximum drag will be almost like the drag generated by a parachute. This guarantees that aerodynamically the vehicle can be braked, so it could be utilized for several missions allowing repeatability of microgravity experiments.

Keywords: microgravity effect, response surface, terminal speed, unmanned system

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Authors: Panagiota Koliousi, Natasha Miaouli

Abstract:

We compare product and labour market liberalization under the two trade union bargaining models: the Right-to-Manage (RTM) model and the Efficient Bargaining (EB) model. The vehicle is a dynamic general equilibrium (DGE) model that incorporates two types of agents (capitalists and workers), imperfectly competitive product and labour markets. The model is solved numerically employing common parameter values and data from the euro area. A key message is that product market deregulation is favourable under any labour market structure while opting for labour market deregulation one should provide special attention to the structure of the labour market such as the bargaining system of unions. If the prevailing way of bargaining is the RTM model then restructuring both markets is beneficial for all agents.

Keywords: market structure, structural reforms, trade unions, unemployment

Procedia PDF Downloads 189