Search results for: Victor H. Benitez
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 208

Search results for: Victor H. Benitez

208 Wireless Sensor Networks for Water Quality Monitoring: Prototype Design

Authors: Cesar Eduardo Hernández Curiel, Victor Hugo Benítez Baltazar, Jesús Horacio Pacheco Ramírez

Abstract:

This paper is devoted to present the advances in the design of a prototype that is able to supervise the complex behavior of water quality parameters such as pH and temperature, via a real-time monitoring system. The current water quality tests that are performed in government water quality institutions in Mexico are carried out in problematic locations and they require taking manual samples. The water samples are then taken to the institution laboratory for examination. In order to automate this process, a water quality monitoring system based on wireless sensor networks is proposed. The system consists of a sensor node which contains one pH sensor, one temperature sensor, a microcontroller, and a ZigBee radio, and a base station composed by a ZigBee radio and a PC. The progress in this investigation shows the development of a water quality monitoring system. Due to recent events that affected water quality in Mexico, the main motivation of this study is to address water quality monitoring systems, so in the near future, a more robust, affordable, and reliable system can be deployed.

Keywords: pH measurement, water quality monitoring, wireless sensor networks, ZigBee

Procedia PDF Downloads 369
207 Experimental Study for the Development of a Wireless Communication System in a Solar Central Tower Facility

Authors: Victor H. Benitez, Ramon V. Armas-Flores, Jesus H. Pacheco-Ramirez

Abstract:

Systems transforming solar energy into electrical power have emerged as a viable source of clean, renewable energy. Solar power tower technology is a good example of this type of system, which consists of several mobile mirrors, called heliostats, which reflect the sun's radiation to the same point, located on top of a tower at the center of heliostat field, for collection or transformation into another type of energy. The so-called Hermosillo’s Solar Platform (Plataforma Solar de Hermosillo, PSH, in Spanish) is a facility constituted with several heliostats, its aim and scope is for research purposes. In this paper, the implementation of a wireless communication system based on intelligent nodes is proposed in order to allow the communication and control of the heliostats in PSH. Intelligent nodes transmit information from one point to another, and can perform other actions that allow them to adapt to the conditions and limitations of a field of heliostats, thus achieving effective communication system. After deployment of the nodes in the heliostats, tests were conducted to measure the effectiveness of the communication, and determine the feasibility of using the proposed technologies. The test results were always positive, exceeding expectations held for its operation in the field of heliostats. Therefore, it was possible to validate the efficiency of the wireless communication system to be implemented in PSH, allowing communication and control of the heliostats.

Keywords: heliostat, intelligent node, solar energy, wireless communication

Procedia PDF Downloads 387
206 One vs. Rest and Error Correcting Output Codes Principled Rebalancing Schemes for Solving Imbalanced Multiclass Problems

Authors: Alvaro Callejas-Ramos, Lorena Alvarez-Perez, Alexander Benitez-Buenache, Anibal R. Figueiras-Vidal

Abstract:

This contribution presents a promising formulation which allows to extend the principled binary rebalancing procedures, also known as neutral re-balancing mechanisms in the sense that they do not alter the likelihood ratio

Keywords: Bregman divergences, imbalanced multiclass classifi-cation, informed re-balancing, invariant likelihood ratio

Procedia PDF Downloads 182
205 Flexicommute: A Web-Based Application to Help with Car Rental Services in the Philippines

Authors: Mico Kenshee C. Samarista, John Harvey V. Miranda, Janne Audrae Q. Lebosada, Josef Anton R. Benitez, Juan Miguel C. Rubio

Abstract:

This research paper presents the development and evaluation of a web-based application designed to simplify the process of car rental services in the Philippines. As the demand for convenient and efficient access to rental car information grows, the need for a user-friendly platform becomes increasingly crucial. The web-based application serves as a comprehensive central hub, aggregating and organizing rental car listings from various reputable websites across the Philippines. By collecting essential data through surveys and usability testing, we assess the platform's effectiveness in simplifying the rental car selection process.

Keywords: web, application, car, services

Procedia PDF Downloads 61
204 Three Issues for Integrating Artificial Intelligence into Legal Reasoning

Authors: Fausto Morais

Abstract:

Artificial intelligence has been widely used in law. Programs are able to classify suits, to identify decision-making patterns, to predict outcomes, and to formalize legal arguments as well. In Brazil, the artificial intelligence victor has been classifying cases to supreme court’s standards. When those programs act doing those tasks, they simulate some kind of legal decision and legal arguments, raising doubts about how artificial intelligence can be integrated into legal reasoning. Taking this into account, the following three issues are identified; the problem of hypernormatization, the argument of legal anthropocentrism, and the artificial legal principles. Hypernormatization can be seen in the Brazilian legal context in the Supreme Court’s usage of the Victor program. This program generated efficiency and consistency. On the other hand, there is a feasible risk of over standardizing factual and normative legal features. Then legal clerks and programmers should work together to develop an adequate way to model legal language into computational code. If this is possible, intelligent programs may enact legal decisions in easy cases automatically cases, and, in this picture, the legal anthropocentrism argument takes place. Such an argument argues that just humans beings should enact legal decisions. This is so because human beings have a conscience, free will, and self unity. In spite of that, it is possible to argue against the anthropocentrism argument and to show how intelligent programs may work overcoming human beings' problems like misleading cognition, emotions, and lack of memory. In this way, intelligent machines could be able to pass legal decisions automatically by classification, as Victor in Brazil does, because they are binding by legal patterns and should not deviate from them. Notwithstanding, artificial intelligent programs can be helpful beyond easy cases. In hard cases, they are able to identify legal standards and legal arguments by using machine learning. For that, a dataset of legal decisions regarding a particular matter must be available, which is a reality in Brazilian Judiciary. Doing such procedure, artificial intelligent programs can support a human decision in hard cases, providing legal standards and arguments based on empirical evidence. Those legal features claim an argumentative weight in legal reasoning and should serve as references for judges when they must decide to maintain or overcome a legal standard.

Keywords: artificial intelligence, artificial legal principles, hypernormatization, legal anthropocentrism argument, legal reasoning

Procedia PDF Downloads 119
203 Students’ Experiential Knowledge Production in the Teaching-Learning Process of Universities

Authors: Didiosky Benítez-Erice, Frederik Questier, Dalgys Pérez-Luján

Abstract:

This paper aims to present two models around the production of students’ experiential knowledge in the teaching-learning process of higher education: the teacher-centered production model and the student-centered production model. From a range of knowledge management and experiential learning theories, the paper elaborates into the nature of students’ experiential knowledge and proposes further adjustments of existing second-generation knowledge management theories taking into account the particularities of higher education. Despite its theoretical nature the paper can be relevant for future studies that stress student-driven improvement and innovation at higher education institutions.

Keywords: experiential knowledge, higher education, knowledge management, teaching-learning process

Procedia PDF Downloads 420
202 The Video Database for Teaching and Learning in Football Refereeing

Authors: M. Armenteros, A. Domínguez, M. Fernández, A. J. Benítez

Abstract:

The following paper describes the video database tool used by the Fédération Internationale de Football Association (FIFA) as part of the research project developed in collaboration with the Carlos III University of Madrid. The database project began in 2012, with the aim of creating an educational tool for the training of instructors, referees and assistant referees, and it has been used in all FUTURO III courses since 2013. The platform now contains 3,135 video clips of different match situations from FIFA competitions. It has 1,835 users (FIFA instructors, referees and assistant referees). In this work, the main features of the database are described, such as the use of a search tool and the creation of multimedia presentations and video quizzes. The database has been developed in MySQL, ActionScript, Ruby on Rails and HTML. This tool has been rated by users as "very good" in all courses, which prompt us to introduce it as an ideal tool for any other sport that requires the use of video analysis.

Keywords: assistants referees, cloud computing, e-learning, instructors, FIFA, referees, soccer, video database

Procedia PDF Downloads 412
201 Jurisprudencial Analysis of Torture in Spain and in the European Human Rights System

Authors: María José Benítez Jiménez

Abstract:

Article 3 of the European Convention for the Protection of Human Rights and Fundamental Freedoms (E.C.H.R.) proclaims that no one may be subjected to torture, punishment or degrading treatment. The legislative correlate in Spain is embodied in Article 15 of the Spanish Constitution, and there must be an overlapping interpretation of both precepts on the ideal plane. While it is true that there are not many cases in which the European Court of Human Rights (E.C.t.H.R. (The Strasbourg Court)) has sanctioned Spain for its failure to investigate complaints of torture, it must be emphasized that the tendency to violate Article 3 of the Convention appears to be on the rise, being necessary to know possible factors that may be affecting it. This paper addresses the analysis of sentences that directly or indirectly reveal the violation of Article 3 of the European Convention. To carry out the analysis, sentences of the Strasbourg Court have been consulted from 2012 to 2016, being able to address any previous sentences to this period if it provided justified information necessary for the study. After the review it becomes clear that there are two key groups of subjects that request a response to the Strasbourg Court on the understanding that they have been tortured or degradingly treated. These are: immigrants and terrorists. Both phenomena, immigration and terrorism, respond to patterns that have mutated in recent years, and it is important for this study to know if national regulations begin to be dysfunctional.

Keywords: E.C.H.R., E.C.t.H.R. sentences, Spanish Constitution, torture

Procedia PDF Downloads 130
200 Study on the Characteristics of Victims and Victimizers of Intimate Partner Violence in Spain and Its Impact on Criminal Intervention

Authors: María José Benitez Jimenez

Abstract:

This research is based on the hypothesis that, despite being found that the problem of violence against the female partner occurs in all social classes, the criminal intervention falls, above all, on victims and aggressors with sociodemographic characteristics of the most excluded social groups. The methodology used in this study has been a collection of information through Spanish official statistics from 2004 to 2016: population, police, judicial and penitentiary data from Ministry of Interior, Ministry of Justice and statistics National Institute. The data provided show that women victims and aggressors who come into contact with criminal intervention bodies for filing a complaint or having been reported, respectively, show a very high percentage, usually well above 50%, only primary studies or even that. Their employment situation is also precarious, in a percentage that could also be around 70%. The percentage distribution of these two variables is clearly above that which occurs in the whole of the Spanish population, in a particularly marked way as regards the employment situation. Immigrants triple, as victims or as aggressors of gender violence, the percentages of the Spanish population in terms of their contact with the organs of criminal intervention. Also the rate of foreign inmates in prisons for violence against the female couple doubles that of Spanish inmates.

Keywords: inmigrants, intimate partner violence, Spain, sociodemographic characteristics

Procedia PDF Downloads 173
199 Sulfate Radicals Applied to the Elimination of Selected Pollutants in Water Matrices

Authors: F. Javier Benitez, Juan L. Acero, Francisco J. Real, Elena Rodriguez

Abstract:

Five selected pollutants which are frequently present in waters and wastewaters have been degraded by the advanced oxidation process constituted by UV radiation activated with the additional presence of persulfate (UV/PS). These pollutants were 1H-benzotriazole (BZ), N,N-diethyl-m-toluamide or DEET (DT), chlorophene (CP), 3-methylindole (ML), and nortriptyline hydrochloride (NH).While UV radiation alone almost not degraded these substances, the addition of PS generated the very reactive and oxidizing sulfate radical SO₄⁻. The kinetic study provided the second order rate constants for the reaction between this radical and each pollutant. An increasing dose of PS led to an increase in the degradation rate, being the highest results obtained at near neutral pH. Several water matrices were tested, and the presence of bicarbonate showed different effects: a decrease in the elimination of DT, BZ, and NH; and an increase in the oxidation of CP and ML. The additional presence of humic acids (AH) decreased this degradation, because of several effects: light screening and radical scavenging. The presence of several natural substances in waters (both types, inorganic and organic matter) usually diminishes the oxidation rates of organic pollutants, but this combination UV/PS process seems to be an efficient solution for the removal of the selected contaminants when are present in contaminated waters.

Keywords: water purification, UV activated persulfate, kinetic study, sulfate radicals

Procedia PDF Downloads 105
198 OAS and Interstate Dispute Resolution at the Beginning of the 21st Century: General Pattern and Peculiarities

Authors: Victor Jeifets, Liliia Khadorich

Abstract:

The paper describes the OAS role in dispute resolution. The authors make an attempt to identify a general pattern of the OAS activities within the peaceful settlement of interstate conflicts, in the beginning of 21st century, as well as to analyze some features of Honduras–Belize, Nicaragua–Honduras, Honduras–El Salvador, Costa-Rica–Nicaragua, Colombia–Ecuador cases.

Keywords: OAS, peace maintenance, border dispute, dispute resolution, peaceful settlement

Procedia PDF Downloads 465
197 Structure-Phase States of Al-Si Alloy After Electron-Beam Treatment and Multicycle Fatigue

Authors: Krestina V. Alsaraeva, Victor E. Gromov, Sergey V. Konovalov, Anna A. Atroshkina

Abstract:

Processing of Al-19.4Si alloy by high intensive electron beam has been carried out and multiple increase in fatigue life of the material has been revealed. Investigations of structure and surface modified layer destruction of Al-19.4Si alloy subjected to multicycle fatigue tests to fracture have been carried out by methods of scanning electron microscopy. The factors responsible for the increase of fatigue life of Al-19.4Si alloy have been revealed and analyzed.

Keywords: Al-19.4Si alloy, high intensive electron beam, multicycle fatigue, structure

Procedia PDF Downloads 523
196 A Robust Implementation of a Building Resources Access Rights Management System

Authors: Eugen Neagoe, Victor Balanica

Abstract:

A Smart Building Controller (SBC) is a server software that offers secured access to a pool of building specific resources, executes monitoring tasks and performs automatic administration of a building, thus optimizing the exploitation cost and maximizing comfort. This paper brings to discussion the issues that arise with the secure exploitation of the SBC administered resources and proposes a technical solution to implement a robust secure access system based on roles, individual rights and privileges (special rights).

Keywords: smart building controller, software security, access rights, access authorization

Procedia PDF Downloads 417
195 Degradation of Amitriptyline Hydrochloride, Methyl Salicylate and 2-Phenoxyethanol in Water Systems by the Combination UV/Cl2

Authors: F. Javier Benitez, Francisco J. Real, Juan Luis Acero, Francisco Casas

Abstract:

Three emerging contaminants (amitriptyline hydrochloride, methyl salicylate and 2-phenoxyethanol) frequently found in waste-waters were selected to be individually degraded in ultra-pure water by the combined advanced oxidation process constituted by UV radiation and chlorine. The influence of pH, initial chlorine concentration and nature of the contaminants was firstly explored. The trend for the reactivity of the selected compounds was deduced: amitriptyline hydrochloride > methyl salicylate > 2-phenoxyethanol. A later kinetic study was carried out and focused on the specific evaluation of the first-order rate constants and the determination of the partial contribution to the global reaction of the direct photochemical pathway and the radical pathway. A comparison between the rate constant values among photochemical experiments without and with the presence of Cl2 reveals a clear increase in the oxidation efficiency of the combined process with respect to the photochemical reaction alone. In a second stage, the simultaneous oxidation of mixtures of the selected contaminants in several types of water (ultrapure water, surface water from a reservoir, and two secondary effluents) was also performed by the same combination UV/Cl2 under more realistic operating conditions. The efficiency of this combined system UV/Cl2 was compared to other oxidants such as the UV/S2O82- and UV/H2O2 AOPs. Results confirmed that the UV/Cl2 system provides higher elimination efficiencies among the AOPs tested.

Keywords: emerging contaminants, UV/chlorine advanced oxidation process, amitriptyline, methyl salicylate, 2-phenoxyethanol, chlorination, photolysis

Procedia PDF Downloads 308
194 Causes of Nigeria Unrest and Conflict Situation

Authors: Victor Osaghae

Abstract:

In 2005, the CIA published a report warning that Nigeria, the seventh most populous country in the world, could disintegrate within 15 years. Nigeria experiences civil unrest, violence and strikes. Nigeria has one of the highest rates of internal violence in the world, only unlike others with similar levels of bloodshed such as Colombia or Chechnya, there is not a civil war going on. The types of unrest observed in Nigeria from literatures consulted can be categorized into five namely: religious, social, political, labour, and communal or ethnic unrests. The cuases of the unrests are as follows: injustice, unemployment, religious intolerance, illiteracy and government not filling agreements reached with unions. The cost due to these unrests cannot be quantified because it affects human, material/properties and money.

Keywords: unrest, conflicts, Boko Haram, disturbance

Procedia PDF Downloads 363
193 Methodology for the Analysis of Energy Efficiency in Pneumatics Systems

Authors: Mario Lupaca, Karol Munoz, Victor De Negri

Abstract:

The present article presents a methodology for the improvement of the energy efficiency in pneumatic systems through the restoring of air. In this way, three techniques of expansion of a cylinder are identified: Expansion using the air of the compressor (conventional), restoring the air (efficient), and combining the air of the compressor and the restored air (hybrid). The methodology starts with the development of the GRAFCET of the system so that it can be decided whether to expand the cylinder in a conventional, efficient, or hybrid way. The methodology can be applied to any case. Finally, graphs of comparison between the three methods of expansion with certain cylinder strokes and workloads are presented, to facilitate the subsequent selection of one system or another.

Keywords: energetic, efficiency, GRAFCET, methodology, pneumatic

Procedia PDF Downloads 283
192 The Platform for Digitization of Georgian Documents

Authors: Erekle Magradze, Davit Soselia, Levan Shughliashvili, Irakli Koberidze, Shota Tsiskaridze, Victor Kakhniashvili, Tamar Chaghiashvili

Abstract:

Since the beginning of active publishing activity in Georgia, voluminous printed material has been accumulated, the digitization of which is an important task. Digitized materials will be available to the audience, and it will be possible to find text in them and conduct various factual research. Digitizing scanned documents means scanning documents, extracting text from the scanned documents, and processing the text into a corresponding language model to detect inaccuracies and grammatical errors. Implementing these stages requires a unified, scalable, and automated platform, where the digital service developed for each stage will perform the task assigned to it; at the same time, it will be possible to develop these services dynamically so that there is no interruption in the work of the platform.

Keywords: NLP, OCR, BERT, Kubernetes, transformers

Procedia PDF Downloads 119
191 Analytical Solutions for Geodesic Acoustic Eigenmodes in Tokamak Plasmas

Authors: Victor I. Ilgisonis, Ludmila V. Konovaltseva, Vladimir P. Lakhin, Ekaterina A. Sorokina

Abstract:

The analytical solutions for geodesic acoustic eigenmodes in tokamak plasmas with circular concentric magnetic surfaces are found. In the frame of ideal magnetohydrodynamics the dispersion relation taking into account the toroidal coupling between electrostatic perturbations and electromagnetic perturbations with poloidal mode number |m| = 2 is derived. In the absence of such a coupling the dispersion relation gives the standard continuous spectrum of geodesic acoustic modes. The analysis of the existence of global eigenmodes for plasma equilibria with both off-axis and on-axis maximum of the local geodesic acoustic frequency is performed.

Keywords: tokamak, MHD, geodesic acoustic mode, eigenmode

Procedia PDF Downloads 709
190 Action Research: Impact of the Health Facilities Infrastructure's Quality on Maternal and Newborn Health

Authors: Ladislas Havugimana, Véronique Zinnen, Mary Hadley, Jean Claude Mwumvaneza, Francois Régis Habarugira, Silas Rudasingwa, Victor Ndaruhutse, Evelyne Bocquet

Abstract:

Rwanda's health systems face various challenges, including low health infrastructure coverage (the objective is to have at least one health center per administrative sector) and insufficient qualified human resources for infrastructure maintenance and financing. Moreover, there is no policy for the preventive maintenance of infrastructures for the health sector. This paper presents action research conducted in seven districts, focusing on the impact of health infrastructure's quality on maternal and neonatal care, with the support of the Belgian cooperation agency through Enable Barame project.

Keywords: health infrastructure, maintenance, maternity, neonatology

Procedia PDF Downloads 118
189 Podemos Party Origin: From Social Protest to Spanish Parliament

Authors: Víctor Manuel Muñoz-Sánchez, Antonio Manuel Pérez-Flores

Abstract:

This paper analyzes the institutionalization of social protest in Spain. In the current crisis Podemos party seems to represent the political positions of the most affected citizens by the economic situation. It studies using quantitative techniques (statistical bivariate analysis), focusing on the exploitation of several bases of statistics data from the Center for Sociological and Research of Spanish Government, 15M movement characterization to its institutionalization in the Podemos party. Making a comparison between the participant's profile by the 15M and the social bases of Podemos votes. Data on the transformation of the socio-demographic profile of the fans, connoisseurs and 15M participants and voters are given.

Keywords: collective action, emerging parties, political parties, social protest

Procedia PDF Downloads 359
188 Graphene-Based Reconfigurable Lens Antenna for 5G/6G and Satellite Networks

Authors: André Lages, Victor Dmitriev, Juliano Bazzo, Gianni Portela

Abstract:

This work evaluates the feasibility of the graphene application to perform as a wideband reconfigurable material for lens antennas in 5G/6G and satellite applications. Based on transformation optics principles, the electromagnetic waves can be efficiently guided by modifying the effective refractive index. Graphene behavior can range between a lossy dielectric and a good conductor due to the variation of its chemical potential bias, thus arising as a promising solution for electromagnetic devices. The graphene properties and a lens antenna comprising multiples layers and periodic arrangements of graphene patches were analyzed using full-wave simulations. A dipole directivity was improved from 7 to 18.5 dBi at 29 GHz. In addition, the realized gain was enhanced 7 dB across a 14 GHz bandwidth within the Ka/5G band.

Keywords: 5G/6G, graphene, lens, reconfigurable, satellite

Procedia PDF Downloads 116
187 Evaluation of Interspecific Pollination of Elaeis guineensis and Elaeis oleifera Carried Out in the Ucayali Region-Peru

Authors: Victor Sotero, Cindy Castro, Ena Velazco, Ursula Monteiro, Dora Garcia

Abstract:

The aim of this study is to carry out the evaluation of the artificial pollination of the female flowers of E. oleifera with pollen of E. guineensis, to obtain the hybrid Palma OXG, which presents two characteristics of interest, such as high resistance to the disease of spear rot and high concentration of oleic acid. The works were carried out with matrices from the experimental fields and INIA in the Province of Colonel Portillo in the Ucayali Region-Peru. From the pollination of five species of E. oleifera, fruits were obtained in two of them, called O7 and O68, with a percentage of 23.6% and 18.6% of fertile fruits. When germination was carried out in a controlled environment of temperature, air, and humidity, only the O17 species were germinated with a yield of 68.7%.

Keywords: Elaeis oleífera, Elaeis guineensis, palm OXG, pollination

Procedia PDF Downloads 115
186 LogiSun: An Interactive Robot to Reduce Pollution on the Beach

Authors: Ruth Manzanares, Victor Honores, Hugo Zapata, Javier Cansaya, Deivid Yavar, Junior Meza

Abstract:

LogiSum is a robot focused on education like a solution to the ecological crisis. This robot allows reducing the pollution on the beaches by stimulating environmental awareness of not contaminating through the collection of waste. Through the use of the methodology of design thinking, it is intended to reinforce values in adults and with a greater focus on children, so as not to contaminate the beaches. The goal is to encourage the use of the container of the robot LogiSum to put the garbage, with visual interaction and simulation of dialogue with the function of the robot. The results obtained of the testings of the interaction of children with the robot showed an encouraging behavior. With the robot, children left the waste in the right places and not bury it in the sand or in the floor.

Keywords: interaction human-robot, pollution reduction, social robot, robot container, beach pollution

Procedia PDF Downloads 242
185 Emerging Technology for 6G Networks

Authors: Yaseein S. Hussein, Victor P. Gil Jiménez, Abdulmajeed Al-Jumaily

Abstract:

Due to the rapid advancement of technology, there is an increasing demand for wireless connections that are both fast and reliable, with minimal latency. New wireless communication standards are developed every decade, and the year 2030 is expected to see the introduction of 6G. The primary objectives of 6G network and terminal designs are focused on sustainability and environmental friendliness. The International Telecommunication Union-Recommendation division (ITU-R) has established the minimum requirements for 6G, with peak and user data rates of 1 Tbps and 10-100 Gbps, respectively. In this context, Light Fidelity (Li-Fi) technology is the most promising candidate to meet these requirements. This article will explore the various advantages, features, and potential applications of Li-Fi technology, and compare it with 5G networking, to showcase its potential impact among other emerging technologies that aim to enable 6G networks.

Keywords: 6G networks, artificial intelligence (AI), Li-Fi technology, Terahertz (THz) communication, visible light communication (VLC)

Procedia PDF Downloads 55
184 Gas-Phase Nondestructive and Environmentally Friendly Covalent Functionalization of Graphene Oxide Paper with Amines

Authors: Natalia Alzate-Carvajal, Diego A. Acevedo-Guzman, Victor Meza-Laguna, Mario H. Farias, Luis A. Perez-Rey, Edgar Abarca-Morales, Victor A. Garcia-Ramirez, Vladimir A. Basiuk, Elena V. Basiuk

Abstract:

Direct covalent functionalization of prefabricated free-standing graphene oxide paper (GOP) is considered as the only approach suitable for systematic tuning of thermal, mechanical and electronic characteristics of this important class of carbon nanomaterials. At the same time, the traditional liquid-phase functionalization protocols can compromise physical integrity of the paper-like material up to its total disintegration. To avoid such undesirable effects, we explored the possibility of employing an alternative, solvent-free strategy for facile and nondestructive functionalization of GOP with two representative aliphatic amines, 1-octadecylamine (ODA) and 1,12-diaminododecane (DAD), as well as with two aromatic amines, 1-aminopyrene (AP) and 1,5-diaminonaphthalene (DAN). The functionalization was performed under moderate heating at 150-180 °C in vacuum. Under such conditions, it proceeds through both amidation and epoxy ring opening reactions. Comparative characterization of pristine and amine-functionalized GOP mats was carried out by using Fourier-transform infrared, Raman, and X-ray photoelectron spectroscopy (XPS), thermogravimetric (TGA) and differential thermal analysis, scanning electron and atomic force microscopy (SEM and AFM, respectively). Besides that, we compared the stability in water, wettability, electrical conductivity and elastic (Young's) modulus of GOP mats before and after amine functionalization. The highest content of organic species was obtained in the case of GOP-ODA, followed by GOP-DAD, GOP-AP and GOP-DAN samples. The covalent functionalization increased mechanical and thermal stability of GOP, as well as its electrical conductivity. The magnitude of each effect depends on the particular chemical structure of amine employed, which allows for tuning a given GOP property. Morphological characterization by using SEM showed that, compared to pristine graphene oxide paper, amine-modified GOP mats become relatively ordered layered assemblies, in which individual GO sheets are organized in a near-parallel pattern. Financial support from the National Autonomous University of Mexico (grants DGAPA-IN101118 and IN200516) and from the National Council of Science and Technology of Mexico (CONACYT, grant 250655) is greatly appreciated. The authors also thank David A. Domínguez (CNyN of UNAM) for XPS measurements and Dr. Edgar Alvarez-Zauco (Faculty of Science of UNAM) for the opportunity to use TGA equipment.

Keywords: amines, covalent functionalization, gas-phase, graphene oxide paper

Procedia PDF Downloads 149
183 Microfluidic Continuous Approaches to Produce Magnetic Nanoparticles with Homogeneous Size Distribution

Authors: Ane Larrea, Victor Sebastian, Manuel Arruebo, Jesus Santamaria

Abstract:

We present a gas-liquid microfluidic system as a reactor to obtain magnetite nanoparticles with an excellent degree of control regarding their crystalline phase, shape and size. Several types of microflow approaches were selected to prevent nanomaterial aggregation and to promote homogenous size distribution. The selected reactor consists of a mixer stage aided by ultrasound waves and a reaction stage using a N2-liquid segmented flow to prevent magnetite oxidation to non-magnetic phases. A milli-fluidic reactor was developed to increase the production rate where a magnetite throughput close to 450 mg/h in a continuous fashion was obtained.

Keywords: continuous production, magnetic nanoparticles, microfluidics, nanomaterials

Procedia PDF Downloads 562
182 Joint Path and Push Planning among Moveable Obstacles

Authors: Victor Emeli, Akansel Cosgun

Abstract:

This paper explores the navigation among movable obstacles (NAMO) problem and proposes joint path and push planning: which path to take and in what direction the obstacles should be pushed at, given a start and goal position. We present a planning algorithm for selecting a path and the obstacles to be pushed, where a rapidly-exploring random tree (RRT)-based heuristic is employed to calculate a minimal collision path. When it is necessary to apply a pushing force to slide an obstacle out of the way, the planners leverage means-end analysis through a dynamic physics simulation to determine the sequence of linear pushes to clear the necessary space. Simulation experiments show that our approach finds solutions in higher clutter percentages (up to 49%) compared to the straight-line push planner (37%) and RRT without pushing (18%).

Keywords: motion planning, path planning, push planning, robot navigation

Procedia PDF Downloads 145
181 Measurement of the Neutron Spectrum of 241AmLi and 241AmF Sources Using the Bonner Sphere Spectrometers

Authors: Victor Rocha Carvalho

Abstract:

The Bonner Sphere Spectrometry was used to obtain the average energy, the fluence rate, and radioprotection quantities such as the personal and ambient dose equivalent of the ²⁴¹AmLi and ²⁴¹AmF isotopic neutron sources used in the Neutron Metrology Laboratory - LN. The counts of the sources were performed with six different spherical moderators around the detector. Through this, the neutron spectrum was obtained by means of the software named NeuraLN, developed by the LN, that uses the neural networks technique. The 241AmLi achieved a result close to the literature, and 241AmF, which contains few published references, acquired a result with a slight variation from the literature. Therefore, besides fulfilling its objective, the work raises questions about a possible standard of the ²⁴¹AmLi and about the lack of work with the ²⁴¹AmF.

Keywords: nuclear physics, neutron metrology, neutron spectrometry, bonner sphere spectrometers

Procedia PDF Downloads 71
180 The Right to Family Reunification of Immigrants in Spain

Authors: María José Benitez Jimenez

Abstract:

This study seeks to make clear the importance of family reunification in order to establish consolidated habits of coexistence of immigrants, directly favoring the relationship of the family nucleus and indirectly the social integration of foreigners. In addition to the theoretical analysis of the subject, information has been reviewed by the National Institute of Statistics and Reports of Spanish organizations that compile data on immigrants and specifically on family reunification. The Spanish regulations on foreigners include the right of foreigners legally residing in Spain to regroup their families. The general conditions required to exercise this right are having legally resided in Spain for one year and having obtained authorization to reside for one more year. There are exceptions to the requirement of having resided for one year in our country. Article 39 of the Spanish Constitution, although it does not express what is to be understood as a family, does refer to the fact that ‘the public authorities ensure the social, economic and legal protection of the family’. Therefore for the Spanish State, the family institution, in a broad sense, enjoys a privileged treatment that is revealed in the Supreme Norm and that reflects the interest of our society to address the relationships that subjects have in their immediate environment. Although we are aware of the reluctant position of the Spanish Constitutional Court to consider as a fundamental right the right to family life despite being enshrined in Article 8 of the European Convention on Human Rights, it is questionable whether access to authorization for family reunification should be more uniform in terms of requirements related to nationality, employment or training of applicants in order to have an egalitarian character. The requirement of having resided one year in Spain to be able to request successful family reunification seems dispensable because if foreigners can obviate this requirement by having a certain status, its abolition would be feasible by equating all situations and benefiting foreigners in general. The achievement of this proposal would help to strengthen the family life of immigrants from the beginning of their life in Spain.

Keywords: family, immigrants, social integration, reunification

Procedia PDF Downloads 321
179 Cyber Security in Nigeria: A Collaboration between Communities and Professionals

Authors: Alese Boniface K., Adu Michael K., Owa Victor K.

Abstract:

Security can be defined as the degree of resistance to, or protection from harm. It applies to any vulnerable and valuable assets, such as persons, dwellings, communities, nations or organizations. Cybercrime is any crime committed or facilitated via the Internet. It is any criminal activity involving computers and networks. It can range from fraud to unsolicited emails (spam). It includes the distant theft of government or corporate secrets through criminal trespass into remote systems around the globe. Nigeria like any other nations of the world is currently having their own share of the menace that has been used even as tools by terrorists. This paper is an attempt at presenting cyber security as an issue that requires a coordinated national response. It also acknowledges and advocates the key roles to be played by stakeholders and the importance of forging strong partnerships to prevent and tackle cybercrime in Nigeria.

Keywords: security, cybercrime, internet, government, stakeholders, partnerships

Procedia PDF Downloads 505