Testing of a New High-Density Concrete as Neutron Shielding Material

We present the testing as neutron shielding material of a new high-density concrete (commercially available under the name Hormirad™, developed by the Spanish company CT-RAD). The purpose of this work was to characterize the material behavior against neutrons, as well as to test different mixings including boron compounds in an effort to improve neutron shielding efficiency. Hormirad™ slabs of different thicknesses were exposed to a 241Am-Be neutron source under controlled conditions in the neutron measurements laboratory of the Nuclear Engineering Department at UPM. The original mix, which includes a high fraction of magnetite, was then modified by adding different proportions of anhydrous borax (Na2B4O7). The same experiment was repeated with HA-25 concrete slabs, looking for a reference against ordinary concrete used to shield medical accelerator facilities. In parallel to the experiments, Monte Carlo calculations of the experiments were performed with MCNP5, with some differences found, attributable to uncertainties in the elemental composition of the samples tested. The first and equilibrium tenth-value layers have been determined for the different types of concrete tested. The results show an advantageous behavior of the Hormirad™ one, when comparing neutron attenuation against real thickness of the shielding. Although borated-concretes show a little better neutron attenuation with respect to mass-thickness, the resulting reduction in density and structural properties makes them less practical

Neutron Shielding Properties of a New High-Density Concrete

The neutron shielding properties of a new high-density concrete (commercially available under the name Hormirad™, developed in Spain by the company CT-RAD) have been characterized both experimentally and by Monte Carlo calculations. The shielding properties of this concrete against photons were previously studied and the material is being used to build bunkers, mazes and doors in medical accelerator facilities with good overall results. In this work, the objective was to characterize the material behavior against neutrons, as well as to test alternative mixings including boron compounds in an effort to improve neutron shielding efficiency. With that purpose, Hormirad™ slabs of different thicknesses were exposed to an 241Am-Be neutron source under controlled conditions in the neutron measurements laboratory of the Nuclear Engineering Department at UPM. The original mix, which includes a high fraction of magnetite, was then modified by adding different proportions of anhydrous borax (Na2B4O7). In order to have a reference against common concrete used to shield medical accelerator facilities, the same experiment was repeated with ordinary (HA-25) concrete slabs. In parallel to the experiments, Monte Carlo calculations of the experiments were performed with MCNP5. The experimental results agree reasonably well with the Monte Carlo calculations. Therefore, the first and equilibrium tenth-value layers have been determined for the different types of concrete tested. The results show an advantageous behavior of the Hormirad™ concrete, in terms of neutron attenuation against real thickness of the shielding. Borated concretes seem less practical since they did not show better neutron attenuation with respect to real thickness and their structural properties are worse. The neutron attenuation properties of Hormirad™ for typical neutron spectra in clinical LINAC accelerators rooms have been also characterized by Monte Carlo calculation

Monte Carlo calculation of the Response Matrix of a Bonner spheres spectrometer

The Bonner spheres spectrometer is utilized to estimate the neutron spectrum of neutrons from thermal up to several MeV neutrons. Its response is increased to few GeV neutrons by introducing large Z materials as inner shells. To use the spectrometer a matrix response and an unfolding method are required; these are crucial to assure the quality of spectrometer output. The response matrix of a Bonner sphere spectrometer was calculated by use of the MCNP code. As thermal neutron counter the spectrometer has a 0.4 Ø × 0.4 cm26LiI(Eu) scintilla or which is located at the centre of a set of polyethylene spheres. The response functions were calculated for 0, 2, 3, 5, 8, 10, and 12 inches-diameter polyethylene spheres for neutrons whose energy goes from 10-8 to 100 MeV. For energies from 10-8 to 20 MeV the MCNP4C code was utilized while for neutrons from 20 to 100 MeV calculations were carried out with MCNPX code. The response functions were compared with those reported in the literature

Response Matrix of a BSS / 6LiI(Eu)

Using Monte Carlo methods the response matrix of a Bonner sphere spectrometer with a6LiI scintillator has been calculated. The response was calculated for 0, 5.08, 7.62, 12.7,20.32, 25.4, and 30.48 cm-diameter polyethylene spheres using twenty three monoenergetic neutron sources whose energy varies from 2.50E(-8) to 100 MeV. The response functions were interpolated to thirty one and fifty one neutron energies and compared with two response functions reported in the literature, a good agreement was found from this comparison. Main differences were found for neutrons whose energy is larger than 20 MeV.For UTA4 response functions differences are also noticed in the lower energy neutrons. These differences are mainly attributed to the cross sections libraries utilized in the different studies

Passive neutron area monitor with pairs of TLDs as neutron detector

A passive neutron area monitor has been designed using Monte Carlo methods; the monitor is a polyethylene cylinder with pairs of thermoluminescent dosimeters (TLD600 and TLD700) as thermal neutron detector. The monitor was calibrated with a bare and a thermalzed 241AmBe neutron sources and its performance was evaluated measuring the ambient dose equivalent due to photoneutrons produced by a 15 MV linear accelerator for radiotherapy and the neutrons in the output of a TRIGA Mark III radial beam port

Neutron features at the UPM neutronics hall

The neutronics hall of the Nuclear Engineering Department at the Polytechnical University of Madrid has been characterized. The neutron spectra and the ambient dose equivalent produced by an 241AmBe source were measured at various source-to-detector distances on the new bench. Using Monte Carlo methods a detailed model of the neutronics hall was designed, and neutron spectra and the ambient dose equivalent were calculated at the same locations where measurements were carried out. A good agreement between measured and calculated values was found

Estudio y análisis de medidor de voltaje controlado por dispositivos móviles

The world’s population is continually growing, and urbanisation is expected to add another 2.5 billion people to cities over the next three decades. Cities have been the epicenter of innovation and technological development. A smart city, is an urban area that uses different types of electronic sensor to collect data. With these data it is possible to manage assets and resources efficiently using the Internet of Things technology that belongs to the domain of Industry 4.0. The smart city concept applied in homes, integrates new information and communication technologies of Industry 4.0, such as ciberphysical systems connected to Internet of things networks through cloud computing applications to optimize the efficiency of home operations and services and connect to citizens. A smart home is one that provides its home owners comfort, security, energy efficiency (low operating costs) and convenience at all times, regardless of whether anyone is home. In this sense, the smart home is a term commonly used to define a residence that has appliances, lighting, heating, air conditioning, TVs, computers, entertainment audio & video systems, security, and camera systems that are capable of communicating with one another and can be controlled remotely by a time schedule, from any room in the home, as well as remotely from any location in the world by phone or internet. However, all the mentioned devices consume electrical energy when they are being used and also when they are not. In this research work, the deveolpment of technology for the smart sensing of electrical consumtion in smart homes in an internet of things environment is presented. This smart device is capable to analize the power consumption of electrical devices connected to electrical power by using mobile devices. The smart meter has a ciberphysical system with an embedded cloud computing application, which can be accesed by movile devices, which is capable to show the electrical consumption of electrical devices when when they are being used and also when they are not. This technological developmento contributes to detect the phantom consumption of electrical energy in order to promote energy saving. The results obtained shows that this technology contributes to the energy saving in smart homes which decreases the economic expense in for home owners and at the same time it allows to observe and analyze the electrical energy consumption of different electrical devices through the use of mobile devices that are connected through the Internet to an application embedded in a cyberphysical system.La población mundial crece continuamente, y se espera que la urbanización agregue otros 2.500 millones de personas a las ciudades durante las próximas tres décadas. Las ciudades han sido el epicentro de la innovación y el desarrollo tecnológico. Una ciudad inteligente, es un área urbana que utiliza diferentes tipos de sensores electrónicos para recopilar datos. Con estos datos es posible administrar activos y recursos de manera eficiente utilizando la tecnología de Internet de las Cosas que pertenece al dominio de la Industria 4.0. El concepto de ciudad inteligente aplicado en los hogares integra las nuevas tecnologías de información y comunicación de la Industria 4.0, como los sistemas ciberfísicos conectados a Internet de las redes de cosas a través de aplicaciones de computación en la nube para optimizar la eficiencia de las operaciones y servicios en el hogar y conectarse con los ciudadanos. Una casa inteligente es aquella que brinda a sus propietarios comodidad, seguridad, eficiencia energética (bajos costos de operación) y conveniencia en todo momento, independientemente de si hay alguien en casa. En este sentido, el hogar inteligente es un término comúnmente utilizado para definir una residencia que tiene electrodomésticos, iluminación, calefacción, aire acondicionado, televisores, computadoras, sistemas de entretenimiento de audio y video, sistemas de seguridad y cámaras que son capaces de comunicarse entre sí. y se puede controlar de forma remota por un horario, desde cualquier habitación de la casa, así como de forma remota desde cualquier lugar del mundo por teléfono o internet. Sin embargo, todos los dispositivos mencionados consumen energía eléctrica cuando se usan y también cuando no. En este trabajo de investigación, se presenta el desarrollo de la tecnología para la detección inteligente del consumo eléctrico en hogares inteligentes en un entorno de Internet de las cosas. Este dispositivo inteligente es capaz de analizar el consumo de energía de los dispositivos eléctricos conectados a la energía eléctrica mediante el uso de dispositivos móviles. El medidor inteligente tiene un sistema ciberfísico con una aplicación integrada de computación en la nube, a la que se puede acceder mediante dispositivos móviles, que es capaz de mostrar el consumo eléctrico de los dispositivos eléctricos cuando se usan y cuando no. Este desarrollo tecnológico contribuye a detectar el consumo fantasma de energía eléctrica para promover el ahorro de energía. Los resultados obtenidos muestran que esta tecnología contribuye al ahorro de energía en hogares inteligentes, lo que disminuye el gasto económico para los propietarios de viviendas y al mismo tiempo permite observar y analizar el consumo de energía eléctrica de diferentes dispositivos eléctricos mediante el uso de dispositivos móviles que están conectados a través de Internet a una aplicación integrada en un sistema ciberfísico

Neutron Spectrum and Dose with Artificial Neural Networks

Artificial neural networks have been applied to unfold the neutron spectra and to calculate the effective dose, the ambient equivalent dose, and the personal dose equivalent for 252Cf, 239PuBe, and 241AmBe neutron sources. The count rates that these neutron sources produce in a Bonner Sphere Spectrometer with a 6LiI (Eu) were utilized as input in both artificial neural networks. Spectra and the ambient dose equivalent were also obtained with BUNKIUT code and the UTA4 response matrix. With both procedures spectra and ambient dose equivalent agrees in less than 10%. The Artificial neural network technology is an alternative procedure to unfold neutron spectra and to perform neutron dosimetry

Neutron spectra and H*(10) around an 18 MV LINAC by ANNs

Neutron spectra and ambient dose equivalent H*(10) were calculated for a radiotherapy room in 16 point-like detectors, 15 located inside the vault room and 1 located outside the bunker. The calculation was carried out using Monte Carlo Methods with the MCNP5 code for a generic radiotherapy room model operating with a 18 MV Linac, obtaining 16 neutron spectra with 47 energy bins, the H*(10) values were calculated from the neutron spectra by the use of the fluence-dose conversion factors. An Artificial Neural Network (ANN) were designed and trained to determine the neutron H*(10) in 15 different locations inside the vault room from the H*(10) dose calculated for the detector located outside the room, using the calculated dose values as training set, using the scaled conjugated gradient training algorithm The mean squared error (mse) set for the network training was 1E(-14), adjusting the data in 99.992 %. In the treatment hall, as the distance respect to the isocenter is increased, the amount of neutrons and the H*(10) are reduced, neutrons in the high-energy region are shifted to lower region peaking around 0.1 MeV, however the epithermal and thermal neutrons remain constant due to the room-return effect. In the maze the spectra are dominated by epithermal and thermal neutrons that contributes to produce activation and the production of prompt gamma-rays. The results shows the using this Artificial Intelligence technic as a useful tool for the neutron spectrometry and dosimetry by the simplification on the neutronic fields characterization inside radiotherapy rooms avoiding the use of traditional spectrometric systems. And once the H*(10) doses have been calculated, to take the appropriated actions to reduce or prevent the patient and working staff exposure to this undesirable neutron radiatio