Search results for: moving obstacles

Authors: Dnyanesh P. Mathur, Gregory L. Slater

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Gravitation and the expansion of the universe at a large scale are generally regarded as two completely distinct phenomena. Yet, in general, relativity theory, they both manifest as 'curvature' of spacetime. We propose a hypothesis which treats these two 'curvature-producing' phenomena as aspects of an underlying process. This process treats spacetime itself as composed of discrete units (Plancktons) and is 'dynamic' in the sense that these elements of spacetime are continually being both created and annihilated. It is these two complementary processes of Planckton creation and Planckton annihilation which manifest themselves as - 'cosmic expansion' on the one hand and as 'gravitational attraction’ on the other. The Planckton hypothesis treats spacetime as a perfect fluid in the same manner as the co-moving frame of reference of Friedman equations and the Gullstrand-Painleve metric; i.e.Planckton hypothesis replaces 'curvature' of spacetime by the 'flow' of Plancktons (spacetime). Here we discuss how this perspective may allow a unified description of both cosmological and gravitational acceleration as well as providing a mechanism for inducing an irreducible action at every point associated with the creation and annihilation of Plancktons, which could be identified as the zero point energy.

Keywords: discrete spacetime, spacetime flow, zero point energy, planktons

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Authors: Zixian Zhang, Shanliang Yao, Zile Huang, Zhaodong Wu, Xiaohui Zhu, Yong Yue, Jieming Ma

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Unmanned Surface Vehicles (USVs) are valuable due to their ability to perform dangerous and time-consuming tasks on the water. Object detection tasks are significant in these applications. However, inherent challenges, such as the complex distribution of obstacles, reflections from shore structures, water surface fog, etc., hinder the performance of object detection of USVs. To address these problems, this paper provides a fusion method for USVs to effectively detect objects in the inland surface environment, utilizing vision sensors and 3+1D Millimeter-wave radar. MMW radar is complementary to vision sensors, providing robust environmental information. The radar 3D point cloud is transferred to 2D radar pseudo image to unify radar and vision information format by utilizing the point transformer. We propose a multi-source object detection network (RV-YOLOX )based on radar-vision fusion for inland waterways environment. The performance is evaluated on our self-recording waterways dataset. Compared with the YOLOX network, our fusion network significantly improves detection accuracy, especially for objects with bad light conditions.

Keywords: inland waterways, YOLO, sensor fusion, self-attention

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Authors: Y. T. Tsai, Jin H. Huang

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The sound pressure level (SPL) of the moving-coil loudspeaker (MCL) is often simulated and analyzed using the lumped parameter model. However, the SPL of a MCL cannot be simulated precisely in the high frequency region, because the value of cone effective area is changed due to the geometry variation in different mode shapes, it is also related to affect the acoustic radiation mass and resistance. Herein, the paper presents the inverse method which has a high ability to measure the value of cone effective area in various frequency points, also can estimate the MCL electroacoustic parameters simultaneously. The proposed inverse method comprises the direct problem, adjoint problem, and sensitivity problem in collaboration with nonlinear conjugate gradient method. Estimated values from the inverse method are validated experimentally which compared with the measured SPL curve result. Results presented in this paper not only improve the accuracy of lumped parameter model but also provide the valuable information on loudspeaker cone design.

Keywords: inverse problem, cone effective area, loudspeaker, nonlinear conjugate gradient method

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Authors: Pedro A. V. Ramos, Duarte M. S. Albuquerque, José C. F. Pereira

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Global warming mitigation is one of the main challenges of this century, having the net balance of greenhouse gas (GHG) emissions to be null or negative in 2050. Industry electrification is one of the main paths to achieving carbon neutrality within the goals of the Paris Agreement. Microwave heating is becoming a popular industrial heating mechanism due to the absence of direct GHG emissions, but also the rapid, volumetric, and efficient heating. In the present study, a mathematical model is used to simulate the production using microwave heating of two ceramic pigments, at high temperatures (above 1200 Celsius degrees). The two pigments studied were the yellow (Pr, Zr)SiO₂ and the brown (Ti, Sb, Cr)O₂. The chemical conversion of reactants into products was included in the model by using the kinetic triplet obtained with the model-fitting method and experimental data present in the Literature. The coupling between the electromagnetic, thermal, and chemical interfaces was also included. The simulations were computed in COMSOL Multiphysics. The geometry includes a moving plunger to allow for the cavity impedance matching and thus maximize the electromagnetic efficiency. To accomplish this goal, a MATLAB controller was developed to automatically search the position of the moving plunger that guarantees the maximum efficiency. The power is automatically and permanently adjusted during the transient simulation to impose stationary regime and total conversion, the two requisites of every converged solution. Both 2D and 3D geometries were used and a parametric study regarding the axial bed velocity and the heat transfer coefficient at the boundaries was performed. Moreover, a Verification and Validation study was carried out by comparing the conversion profiles obtained numerically with the experimental data available in the Literature; the numerical uncertainty was also estimated to attest to the result's reliability. The results show that the model-fitting method employed in this work is a suitable tool to predict the chemical conversion of reactants into the pigment, showing excellent agreement between the numerical results and the experimental data. Moreover, it was demonstrated that higher velocities lead to higher thermal efficiencies and thus lower energy consumption during the process. This work concludes that the electromagnetic heating of materials having high loss tangent and low thermal conductivity, like ceramic materials, maybe a challenge due to the presence of hot spots, which may jeopardize the product quality or even the experimental apparatus. The MATLAB controller increased the electromagnetic efficiency by 25% and global efficiency of 54% was obtained for the titanate brown pigment. This work shows that electromagnetic heating will be a key technology in the decarbonization of the ceramic sector as reductions up to 98% in the specific GHG emissions were obtained when compared to the conventional process. Furthermore, numerical simulations appear as a suitable technique to be used in the design and optimization of microwave applicators, showing high agreement with experimental data.

Keywords: automatic impedance matching, ceramic pigments, efficiency maximization, high-temperature microwave heating, input power control, numerical simulation

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Authors: Eudjen Cinc

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The contemporary society, which is, whether we like it or not, oriented towards utilitarianism, pragmatics and professional flexibility, lives in a certain paradox. On the one hand, at least declaratively, the accent of modern society is on knowledge; knowledge is even considered to be a commodity, the popularity of education is increased as the only means of survival in the market-oriented world, while on the other hand modern society is moving towards simplification and decreasing the amount of information and areas which are considered necessary in the generally excepted concept of education. We cannot talk about the preschool teacher profession without mentioning work with gifted children. The preschool teacher knowing the characteristics of gifted children is of utmost importance because their early identification and professional guidance are of cardinal importance for the direction in which the children will develop. When we talk about musical ability, in the first phase, the role of preschool teachers in the identification and stimulation of gifted children naturally refers to monitoring children’s musical manifestation. The identification process and work with the gifted presupposes a good relationship with the family, synergy of these two important influences in the child’s education and upbringing.

Keywords: music education, gifted children, methodology, kindergarten

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Authors: Sepinoud Hamedi

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Over the past few decades, companies have appeared developing concerns in connection to the natural affect of their fabricating exercises. Green supply chain administration has been considered by the producers as a attainable choice to decrease the natural affect of operations whereas at the same time moving forward their operational execution. Contemporaneously the coming of digitalization and globalization within the supply chain space has driven to a developing acknowledgment of the importance of data preparing methodologies, such as enormous information analytics and fake insights innovations, in improving and optimizing supply chain execution. Also, supply chain collaboration in part intervenes the relationship between manufactured innovation and supply chain execution Ponders appear that the use of BDA-AI advances includes a significant impact on natural handle integration and green supply chain collaboration conjointly underlines that both natural handle integration and green supply chain collaboration have a critical affect on natural execution. Correspondingly savvy supply chain contributes to green execution through overseeing green connections and setting up green operations.

Keywords: green supply chain, artificial intelligence, manufacturers, technology, environmental

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Authors: Summer Jackson

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September 11, 2001 terrorist attacks exposed weaknesses in federal law enforcement’s ability to proactively counter threats to American homeland security. Following the attacks, legislative reforms and policy changes cleared both bureaucratic and legal obstacles to anti-terrorism efforts. The Federal Bureau of Investigation (FBI) transformed into a domestic intelligence agency responsible for preventing future terrorist attacks. Likewise, the passage of the 2001 USA Patriot Act gave federal agents new discretionary powers to more easily collect intelligence on those suspected of supporting terrorism. Despite these changes, there has been only limited scholarly attention paid to terrorism responses by the federal criminal justice system. This study sought to examine the investigative and prosecutorial changes made in the Post-9/11 era. The methodology employed bivariate and multivariate statistics using data from the American Terrorism Study (ATS). This analysis examined how policy changes are reflected in the nature of terrorism investigations, the handling of terrorist defendants by federal prosecutors, and the outcomes of terrorism cases since 2001. The findings indicate significant investigative and prosecutorial changes in the Post-9/11 era. Specifically, this study found terrorism cases involved younger defendants, fewer indictees per case, less use of human intelligence, less complicated attacks, less serious charges, and more plea bargains. Overall, this study highlights the important shifts in responses to terrorism following the 9/11 attacks.

Keywords: terrorism, law enforcement, post-9/11, federal policy

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Authors: Somesh Kumar Sharma, Sunanad Gupta

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The contribution of aviation to society and economy is undisputedly significant. The aviation industry drives economic and social progress by contributing prominently to tourism, commerce and improved quality of life. Identifying the amount of fuel consumed by an aircraft while moving in both airspace and ground networks is critical to air transport economics. Aviation fuel is a major operating cost parameter of the aviation industry and at the same time it is prone to various constraints. This article aims to develop a model for fuel consumption of aviation product. The paper tailors the information for the fuel consumption optimization in terms of information development, information evaluation and information refinement. The information is evaluated and refined using statistical package R and Factor Analysis which is further validated with neural networking. The study explores three primary dimensions which are finally summarized into 23 influencing variables in contrast to 96 variables available in literature. The 23 variables explored in this study should be considered as highly influencing variables for fuel consumption which will contribute significantly towards fuel optimization.

Keywords: fuel consumption, civil aviation industry, neural networking, optimization

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Authors: Abiodun Ayodele Sanyaolu

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The research was carried out to investigate the time series analysis on quarterly production of fruit juice at the National Horticultural Research Institute Ibadan from 2010 to 2018. Documentary method of data collection was used, and the method of least square and moving average were used in the analysis. From the calculation and the graph, it was glaring that there was increase, decrease, and uniform movements in both the graph of the original data and the tabulated quarter values of the original data. Time series analysis was used to detect the trend in the highest number of fruit juice and it appears to be good over a period of time and the methods used to forecast are additive and multiplicative models. Since it was observed that the production of fruit juice is usually high in January of every year, it is strongly advised that National Horticultural Research Institute should make more provision for fruit juice storage outside this period of the year.

Keywords: fruit juice, least square, multiplicative models, time series

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Authors: Myeong Hee Jeong, Man Young Kim

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The use of perforated plate and tubes is common in applications such as vehicle exhaust silencers, attenuators in air moving ducts and duct linings in jet engines. Also, perforated plate flow conditioners designed to improve flow distribution upstream of an orifice plate flow meter typically have 50–60% free area but these generally employ a non-uniform distribution of holes of several sizes to encourage the formation of a fully developed pipe flow velocity distribution. In this study, therefore, numerical investigations on the flow characteristics with the various perforated plates have been performed and then compared to the case without a perforated plate. Three different models are adopted such as a flat perforated plate, a convex perforated plate in the direction of the inlet, and a convex perforated plate in the direction of the outlet. Simulation results show that the pressure drop with and without perforated plates are similar each other. However, it can be found that that the different shaped perforated plates influence the velocity contour, flow uniformity index, and location of the fully developed fluid flow. These results can be used as a practical guide to the best design of pipe with the perforated plate.

Keywords: perforated plate, flow uniformity, pipe turbulent flow, CFD (Computational Fluid Dynamics)

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Authors: Rusmawati Said, N. Kar Yee, Asmaddy Haris

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This study employs a panel data set of ASEAN member states, 17 European Union (EU) countries, 7 American countries and 11 other Asia Pacific countries (China Mainland and Hong Kong SAR are treated as two separated countries) to investigate the role of labour standards in explaining the pattern of bilateral migration flows in ASEAN. Using pooled Ordinary Least Square (OLS) this study found mixed results. The result varies on how indicators were used to measure the level of labour standards in the empirical analysis. In one side, better labour standards (represented by number of strikes and weekly average working hours) promote bilateral migration among the selected countries. On the other side, increase in cases of occupational injuries lead to an increase in bilateral migration, reflecting that worsen in working conditions do not influence the workers’ decision from moving. The finding from this study become important to policy maker as the issues of massive low skilled workers have a significant impact to the role of labour standard in shaping the migration flows.

Keywords: labour standard, migration, ASEAN, economics and financial engineering

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Authors: Fazilet Alachaher

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Within the constructivist perspective of teaching, which views skilled teaching as knowing what to do in uncertain and unpredictable situations, this research essay explores the topic of reflective teaching by investigating the following questions: (1) What is reflective teaching and why is it important? (2) Why should teachers be trained to be reflective and how can they be prepared to be reflective? (3) What is the role of the teaching context in teachers’ attempts to be reflective? This paper suggests that reflective teaching is important because of the various potential benefits to teaching. Through reflection, teachers can maintain their voices and creativeness thus have authority to affect students, curriculum and school policies. The discussions also highlight the need to prepare student teachers and their professional counterparts to be reflective, so they can develop the characteristics of reflective teaching and gain the potential benefits of reflection. This can be achieved by adopting models and techniques that are based on constructivist pedagogical approaches. The paper also suggests that maintaining teachers’ attempts to be reflective in a workplace context and aligning practice with pre-service teacher education programs require the administrators or the policy makers to provide the following: sufficient time for teachers to reflect and work collaboratively to discuss challenges encountered in teaching, fewer non-classroom duties, regular in-service opportunities, more facilities and freedom in choosing suitable ways of evaluating their students’ progress and needs.

Keywords: creative teaching, reflective teaching, constructivist pedagogical approaches, teaching context, teacher’s role, curriculum and school policies, teaching context effect

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Authors: Vladimir Stojanović, Marko D. Petković

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The vibration of a complex bogie system that moves on along the high order shear deformable beam on a viscoelastic foundation is studied. The complex bogie system has been modeled by elastically connected rigid bars on an identical supports. Elastic coupling between bars is introduced to simulate rigidly or flexibly (transversal or/and rotational) connection. Identical supports are modeled as a system of attached spring and dashpot to the bar on one side and interact with the beam through the concentrated mass on the other side. It is assumed that the masses and the beam are always in contact. New analytically determined critical velocity of the system is presented. It is analyzed the case when the complex bogie system exceeds the minimum phase velocity of waves in the beam when the vibration of the system may become unstable. Effect of an elastic coupling between bars on the stability of the system has been analyzed. The instability regions are found for the complex bogie system by applying the principle of the argument and D-decomposition method.

Keywords: Reddy-Bickford beam, D-decomposition method, principle of argument, critical velocity

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Authors: Martin Doran, Roy Sterritt, George Wilkie

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NASA, ESA, and NSSC space agencies have plans to put planetary rovers on Mars in 2020. For these future planetary rovers to succeed, they will heavily depend on sensors to detect obstacles. This will also become of vital importance in the future, if rovers become less dependent on commands received from earth-based control and more dependent on self-configuration and self-decision making. These planetary rovers will face harsh environments and the possibility of hardware failure is high, as seen in missions from the past. In this paper, we focus on using Autonomic principles where self-healing, self-optimization, and self-adaption are explored using the MAPE-K model and expanding this model to encapsulate the attributes such as Awareness, Analysis, and Adjustment (AAA-3). In the experimentation, a Pioneer P3-DX research robot is used to simulate a planetary rover. The sonar sensors on the P3-DX robot are used to simulate the sensors on a planetary rover (even though in reality, sonar sensors cannot operate in a vacuum). Experiments using the P3-DX robot focus on how our software system can be adapted with the loss of sonar sensor functionality. The autonomic manager system is responsible for the decision making on how to make use of remaining ‘enabled’ sonars sensors to compensate for those sonar sensors that are ‘disabled’. The key to this research is that the robot can still detect objects even with reduced sonar sensor capability.

Keywords: autonomic, self-adaption, self-healing, self-optimization

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Authors: Getnet Ayele Kebede, Tasew Tadiwose Zewdie

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In this study, a novel design of a wind-powered water pump for small-scale irrigation application by using the Savonius wind turbine of Vertical Axis Wind Turbine(VAWT) with 2 blades has been used. Calculations have been made on the energy available in the wind and an energy analysis was then performed to see what wind speed is required for the system to work. The rotor has a radius of 0.53 m giving a swept area of 1.27 m2 and this gives a solidity of 0.5, which is the minimum theoretical optimum value for wind turbine. The average extracted torque of the wind turbine is 0.922 Nm and Tip speed ratio is one this shows, the tips are moving at equal the speed of the wind and by 2 rotating of blades. This is sufficient to sustain the desired flow rate of (0.3125X 10-3) m3 per second with a maximum head of 10m and the expected working is 4hr/day, and also overcome other barriers to motion such as friction. Based on this novel design, we are able to achieve a cost-effective solution and simultaneously effective in self-starting under low wind speeds and it can catch the wind from all directions.

Keywords: Savonius wind turbine, Small-scale irrigation, Vertical Axis Wind Turbine, Water pump

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Authors: Carlos Gordon, Patricio Encalada, Henry Lema, Diego Leon, Dennis Chicaiza

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The following work presents a proposal of autonomous navigation of mobile robots implemented in an omnidirectional robot Kuka Youbot. We have been able to perform the integration of robotic operative system (ROS) and machine learning algorithms. ROS mainly provides two distributions; ROS hydro and ROS Kinect. ROS hydro allows managing the nodes of odometry, kinematics, and path planning with statistical and probabilistic, global and local algorithms based on Adaptive Monte Carlo Localization (AMCL) and Dijkstra. Meanwhile, ROS Kinect is responsible for the detection block of dynamic objects which can be in the points of the planned trajectory obstructing the path of Kuka Youbot. The detection is managed by artificial vision module under a trained neural network based on the single shot multibox detector system (SSD), where the main dynamic objects for detection are human beings and domestic animals among other objects. When the objects are detected, the system modifies the trajectory or wait for the decision of the dynamic obstacle. Finally, the obstacles are skipped from the planned trajectory, and the Kuka Youbot can reach its goal thanks to the machine learning algorithms.

Keywords: autonomous navigation, machine learning, path planning, robotic operative system, open source computer vision library

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Authors: Lele Dominic Dummene

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Economic development and environmental development have been a long-lasting debate between capitalist and environmentalist. It is also seen as a debate between modernisation, globalisation at one end, and environmental justice at the other end. Our society today is moving rapidly towards development and increased industrial revolutions, and globalisation. Indigenous communities in Ogoniland are also experiencing such development due to multinationals’ exploration of crude oil in the communities. The oil exploration activities have caused environmental, socio-economic, health, and political problems in indigenous communities in Ogoniland. These issues require depth understanding from all sectors (public, government, and corporate sectors) to address them. Hence, this paper presents the types of environmental education programs used in indigenous communities in Ogoniland to address environmental issues and other problems caused by oil exploration in Ogoniland, Nigeria. These environmental education programs contributes to environmental policy creation, development of environmental curriculum, and pragmatic actions towards mitigating environmental degradation and related environmental socio-economic and political issues in indigenous communities.

Keywords: environmental education, indigenous communities, environmental problems, ogoniland

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Authors: Stephen D. Caldes

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Teaching media and digital literacy to “digital natives” presents a unique set of pedagogical obstacles, especially when critique is involved, as these early-adopters tend to deify most technological and/or digital advancements and inventions. Knowing no other way of being, these natives are often reluctant to hear criticisms of the way they receive information, educate themselves, communicate with others, and even become enculturated because critique often connotes generational gaps and/or clandestine efforts to produce neo-Luddites. To digital natives, techno-criticism is more the result of an antiquated, out-of-touch agenda rather than a constructive, progressive praxis. However, the need to cultivate a techno-critical perspective among technology’s premier users has, perhaps, never been more pressing. In an effort to sidestep reluctance and encourage critical thought about where we are in terms of digital technology and where exactly it may be taking us, this essay outlines a new model for teaching techno-criticism to digital natives. Specifically, it recasts the techniques of participatory journalism—helping writers and readers understand subjects outside of their specific historical context—as progressive, interdisciplinary pedagogy. The model arises out of a review of relevant literature and data gathered via literary analysis and participant observation. Given the tenuous relationships between novel digital advancements, individual identity, collective engagement, and, indeed, Truth/fact, shepherding digital natives toward routine practice of “techno-realism” seems of utter importance.

Keywords: digital natives, journalism education, media literacy, techno-criticism

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Authors: Sarah Elmammeri

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This paper will represent the postcolonial every day in the journey of asylum seekers through the asylum process in the UK. It represents everyday borders, which are defined as everyday barriers, and obstacles facing asylum seekers and refugees in the host country. These everyday barriers can be legal, financial, social and educational under the umbrella of the racialized administrative border creating a package. The arguments build on a set of 21 semi-structured interviews in English and Arabic. The interviews were conducted in the UK, online via zoom lasting between 25 minutes and 2 hours with asylum seekers, refugees, Non-governmental organisations workers and volunteers. The interviews focus on the meaning of borders both physical and metaphorical and ways to challenge the ongoing postcolonial everyday border practices. The findings conclude that these barriers are there deliberately and intentionally to target asylum seekers and limit their legal right to claim asylum in a form of policy and regulations. People in the asylum process, NGO workers, and refugees relate to this aspect of the everyday borders. Second, these barriers come intertwined together creating a structure that interferes with the daily life of an asylum seeker and later affects people with refugee status creating racialised barriers starting with the structural and official form of it: the asylum process. These structural barriers will be linked forming a multi-level barrier enhancing the racialisation of people who are categorised and selected.

Keywords: everyday borders, asylum policies, inclusion and exclusion, refugees and asylum seekers

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Authors: Deni Stincer Gomez, Zuraya Monroy Nasr, Luis Pérez Alvarez

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The preparation of academic documents such as thesis, articles and research projects is one of the requirements of the higher educational level. These documents demand the implementation of logical argumentative thinking which is experienced and executed with difficulty. To mitigate the effect of these difficulties this study designed a thesis seminar, with which the authors have seven years of experience. It is taught in a graduate program in Psychology at the National Autonomous University of Mexico. In this study the authors use the Toulmin model as a mental heuristic and for the application of a set of psychodidactic strategies that facilitate the elaboration of the plot and culmination of the thesis. The efficiency in obtaining the degree in the groups exposed to the seminar has increased by 94% compared to the 10% that existed in the generations that were not exposed to the seminar. In this article the authors will emphasize the psychodidactic strategies used. The Toulmin model alone does not guarantee the success achieved. A set of actions of a psychological nature (almost psychotherapeutic) and didactics of the teacher also seem to contribute. These are actions that derive from an understanding of the psychological, epistemological and ontogenetic obstacles and the most frequent errors in which thought tends to fall when it is demanded a logical course. The authors have grouped the strategies into three groups: 1) strategies to facilitate logical thinking, 2) strategies to strengthen the scientific self and 3) strategies to facilitate the act of writing the text. In this work the authors delve into each of them.

Keywords: psychodidactic strategies, logical thinking, academic documents, Toulmin model

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Authors: Tasuku Hongo, Hiroya Mamori, Naoya Fukushima, Makoto Yamamoto

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A tsunami induced by an earthquake gives a severe disaster in coastal area. As well known, the huge earthquake in Japan 2011 induced a huge tsunami and the tsunami caused serious damage in the Tohoku and Kanto area. Although breakwaters were constructed in the coast to suppress the tsunami, these were collapsed, and it resulted in severe disasters. In order to decrease the tsunami disaster, we propose the submerged breakwaters and investigate its effect on the tsunami behavior by means of numerical simulations. In order to reproduce tsunami and capture its interface, we employed a moving particle method which is one of the Lagragian methods. Different from ordinary breakwaters, the present breakwater is located in the under-sea. An effective installation condition is investigated by the parametric study. The results show that the submerged breakwater can decrease the wave force by the tsunami. Moreover, the combination of two submerged breakwaters can reduce the tsunami safely and effectively. Therefore, the present results give the effective condition of the installation of the under-sea breakwaters and its mechanism.

Keywords: coastal area, tsunami force reduction, MPS method, submerged breakwater

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Authors: Ruwan Gunawardane

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This paper attempts to emphasize the benefits of conducting an intensive course in English for university entrants. In the Sri Lankan university context, an intensive course in English is usually conducted amidst various obstacles. In the 1970s and 1980s, undergraduates had intensive programmes in English for two to three months. Towards the end of the 1990s, a programme called General English Language Training (GELT) was conducted for the new students, and it was done outside universities before they entered their respective universities. Later it was not conducted, and that also resulted in students’ poor performance in English at university. However, having understood its importance, an eight week long intensive course in English was conducted for the new intake of the Faculty of Science, University of Ruhuna. As the findings show, the students heavily benefited from the programme. More importantly, they had the opportunity to refresh their knowledge of English gained at school and private institutions while gaining new knowledge. Another advantage was that they had plenty of time to enjoy learning English since the learners had adequate opportunities to carry out communicative tasks and the course was not exam-oriented, which reduced their fear of making mistakes in English considerably. The data was collected through an open-ended questionnaire given to 60 students, and their oral feedback was also taken into consideration. In addition, a focus group interview with 6 teachers was also conducted to get an idea about their experience and perception. The data were qualitatively analyzed. The findings suggest that an intensive programme in English undoubtedly lays a good foundation for the students’ academic career at university.

Keywords: intensive course, English, teachers, undergraduates, experience, perception

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Authors: Kristina Horvat Blazinovic

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In the context of a work of art, one can talk about the idea-concept-term-intention expressed by the artist by using various forms of repetition (external, material, visible repetition). Such repetitions of elements (images in space or moving visual and sound images in time) suggest a "covert", "latent" ("dressed") repetition – i.e., "hidden", "latent" term-intention-idea. Repeating in this way reveals a "deeper truth" that the viewer needs to decode and which is hidden "under" the technical manifestation of the multiplied images. It is not only images, sounds, and screens that are repeated - something else is repeated through them as well, even if, in some cases, the very idea of repetition is repeated. This paper examines serial images and single-channel or multi-channel artwork in the field of video/film art and video installations, which in a way implies the concept of repetition and multiplication. Moving or static images and screens (as multi-screens) are repeated in time and space. The categories of the real and the symbolic partly refer to the Lacan registers of reality, i.e., the Imaginary - Symbolic – Real trinity that represents the orders within which human subjectivity is established. Authors such as Bruce Nauman, VALIE EXPORT, Ragnar Kjartansson, Wolf Vostell, Shirin Neshat, Paul Sharits, Harun Farocki, Dalibor Martinis, Andy Warhol, Douglas Gordon, Bill Viola, Frank Gillette, and Ira Schneider, and Marina Abramovic problematize, in different ways, the concept and procedures of multiplication - repetition, but not in the sense of "copying" and "repetition" of reality or the original, but of repeated repetitions of the simulacrum. Referential works of art are often connected by the theme of the traumatic. Repetitions of images and situations are a response to the traumatic (experience) - repetition itself is a symptom of trauma. On the other hand, repeating and multiplying traumatic images results in a new traumatic effect or cancels it. Reflections on repetition as a temporal and spatial phenomenon are in line with the chapters that link philosophical considerations of space and time and experience temporality with their manifestation in works of art. The observations about time and the relation of perception and memory are according to Henry Bergson and his conception of duration (durée) as "quality of quantity." The video works intended to be displayed as a video loop, express the idea of infinite duration ("pure time," according to Bergson). The Loop wants to be always present - to fixate in time. Wholeness is unrecognizable because the intention is to make the effect infinitely cyclic. Reflections on time and space end with considerations about the occurrence and effects of time and space intervals as places and moments "between" – the points of connection and separation, of continuity and stopping - by reference to the "interval theory" of Soviet filmmaker DzigaVertov. The scale of opportunities that can be explored in interval mode is wide. Intervals represent the perception of time and space in the form of pauses, interruptions, breaks (e.g., emotional, dramatic, or rhythmic) denote emptiness or silence, distance, proximity, interstitial space, or a gap between various states.

Keywords: video installation, performance, repetition, multi-screen, real and symbolic, loop, video art, interval, video time

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Authors: Shu-Hsien Liao, Yao-Hsuan Yang

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Social media is a virtual community and online platform that people use to create, share, and exchange opinions/experiences. Internet celebrities are people who become famous on the Internet, increasing their popularity through their social networking or video websites. Social commerce (s-ecommerce) is the combination of social relations and commercial transaction activities. The combination of social media and Internet celebrities is an emerging model for the development of s-ecommerce. With recent advances in system sciences, recommendation systems are gradually moving to develop intentional and behavioral recommendations. This background leads to the research issues regarding digital and social media in enterprises. Thus, this study implements data mining analytics, including clustering analysis and association rules, to investigate Taiwanese users (n=2,102) to investigate social media and Internet celebrities’ preferences to find knowledge profiles/patterns/rules for s-ecommerce intentional and behavioral recommendations.

Keywords: social media, internet celebrity, social commerce (s-ecommerce), data mining analytics, intentional and behavioral recommendations

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Authors: Seyed Esmail Seyedi Bariran, Khairul Salleh Mohamed Sahari

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In robotics literature, the simultaneous localization and mapping (SLAM) is commonly associated with a priori-posteriori problem. The autonomous vehicle needs a neutral map to spontaneously track its local position, i.e., “localization” while at the same time a precise path estimation of the environment state is required for effective route planning and obstacle avoidance. On the other hand, the environmental noise factors can significantly intensify the inherent uncertainties in using odometry information and measurements obtained from the robot’s exteroceptive sensor which in return directly affect the overall performance of the corresponding SLAM. Therefore, the current work is primarily dedicated to provide a diagnostic analysis of six SLAM algorithms including FastSLAM, L-SLAM, GraphSLAM, Grid SLAM and DP-SLAM. A SLAM simulated environment consisting of two sets of landmark locations and robot waypoints was set based on modified EKF and UKF in MATLAB using two separate maps for indoor and outdoor route planning subject to natural and artificial obstacles. The simulation results are expected to provide an unbiased platform to compare the estimation performances of the five SLAM models as well as on the reliability of each SLAM model for indoor and outdoor applications.

Keywords: route planning, obstacle, estimation performance, FastSLAM, L-SLAM, GraphSLAM, Grid SLAM, DP-SLAM

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Authors: Benoit Rougier, Alexandre Lefrancois, Herve Aubert

Abstract:

Microwave interrogation in the range 10-100 GHz is identified as an advanced technique to investigate simultaneously shock and particle velocity measurements. However, it requires the understanding of electromagnetic wave propagation in a multi-layered moving media. The existing models limit their approach to wave guides or evaluate the velocities with a fitting method, restricting therefore the domain of validity and the precision of the results. Moreover, few data of permittivity on high explosives at these frequencies under dynamic compression have been reported. In this paper, shock and particle velocities are computed concurrently for steady and unsteady shocks for various inert and reactive materials, via a propagation model based on Doppler shifts and signal amplitude. Refractive index of the material under compression is also calculated. From experimental data processing, it is demonstrated that Hugoniot curve can be evaluated. The comparison with published results proves the accuracy of the proposed method. This microwave interrogation technique seems promising for shock and detonation waves studies.

Keywords: electromagnetic propagation, experimental setup, Hugoniot measurement, shock propagation

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Authors: Khaled A. Madi, Rema A. Mousbahi, Mostafa B. Abuitbel, Abdualhakim O. Nagi

Abstract:

Antenna perhaps is the most important part of any communication system, it determines the overall efficiency and the direction of radiation of the system. Antennas vary in shape and size on a very wide range. For fast moving vehicles, the antenna should offer as litter aerodynamic resistance as possible. Slot antenna is best suited for this purpose. It offers very little aerodynamic resistance, compact, easy to feed and fabricate. This work presented in this paper deals with the investigation of a half wave slot antenna. The antenna has been studied, analyzed, designed, simulated, fabrication, and tested at the X-band. The field of antenna study is an extremely vast one, and to grasp the fundamentals, two pronged approaches have been used, and the focus was on the fabrication and testing of a slot waveguide directional antenna. Focuses on the design and simulation of slot antennas with an emphasis on optimization of a 9.1 GHz a rectangular waveguide have been used to feed slot antenna. A microwave fed slot antenna used in the communication lab was also simulated. The results have been presented and compared with the expected values, where a good agreement was achieved between the simulation and experimental results.

Keywords: microwave, slot antenna, simulation, fabrication

Procedia PDF Downloads 122

Authors: Nuo Xu, Kok Hun Goh, Jeyatharan Kumarasamy

Abstract:

Pile load testing is significant during foundation construction due to its traditional role of design validation and routine quality control of the piling works. In order to verify whether piles can take loadings at specified settlements, piles will have to undergo working load test where the test load should normally up to 150% of the working load of a pile. Selection or sampling of piles for the working load test is done subject to the number specified in Singapore National Annex to Eurocode 7 SS EN 1997-1:2010. This paper presents an innovative way to rationalize the number of pile load test by adopting statistical analysis approach and looking at the coefficient of variance of pile elastic modulus using a case study at Singapore Tuas depot. Results are very promising and have shown that it is possible to reduce the number of working load test without influencing the reliability and confidence on the pile quality. Moving forward, it is suggested that more load test data from other geological formations to be examined to compare with the findings from this paper.

Keywords: elastic modulus of pile under soil interaction, jurong formation, kentledge test, pile load test

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Authors: Sidharth Talan, Rajlakshmi G. Majumdar

Abstract:

Problem-solving skill is one the few skills which is constantly endeavored to improve upon by the professionals and academicians around the world in order to sustain themselves in the ever-growing competitive environment. The given paper focuses on evaluating a hypothesized relationship between the problems solving efficiency of an individual with spaced repetitions, conducted with a time interval of one day over a period of two weeks. The paper has utilized uni-variate regression analysis technique to assess the best fit curve that can explain the significant relationship between the given two variables. The paper has incorporated Anagrams solving as the appropriate testing process for the analysis. Since Anagrams solving involves rearranging a jumbled word to form a correct word, it projects to be an efficient process to observe the attention span, visual- motor coordination and the verbal ability of an individual. Based on the analysis for a sample population of 30, it was observed that problem-solving efficiency of an individual, measured in terms of the score in each test was found to be significantly correlated with time period measured in days.

Keywords: Anagrams, histogram plot, moving average curve, spacing effect

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Authors: O. J. G. Somsen, G. P. M. Wagemakers

Abstract:

Magnetic signature detection provides sensitive detection of metal objects, especially in the natural environment. Our group is developing a tabletop setup for magnetic signatures of various small and model objects. A particular issue is the separation of permanent and induced magnetization. While the latter depends only on the composition and shape of the object, the former also depends on the magnetization history. With common deperming techniques, a significant permanent signature may still remain, which confuses measurements of the induced component. We investigate a basic technique of separating the two. Measurements were done by moving the object along an aluminum rail while the three field components are recorded by a detector attached near the center. This is done first with the rail parallel to the Earth magnetic field and then with anti-parallel orientation. The reversal changes the sign of the induced- but not the permanent magnetization so that the two can be separated. Our preliminary results on a small iron block show excellent reproducibility. A considerable permanent magnetization was indeed present, resulting in a complex asymmetric signature. After separation, a much more symmetric induced signature was obtained that can be studied in detail and compared with theoretical calculations.

Keywords: magnetic signature, data analysis, magnetization, deperming techniques

Procedia PDF Downloads 445