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To improve the irradiation accuracy in hadron therapy, a lot of studies are in the evaluation uncluding how to integrate MRI and PET at the treatment of cancer patients. These two future techniques ...will offer simultaneously the monitoring of the beam during the irradiation. In this study and for the first time, we calculated the dose distribution in a head volume for several carbon ion energies and at different values of the magnetic field
B
using fluka MC code. Afterwards, either longitudinal or radial dose deflection was simulated with and without
B
. Basically, the
Z
axis is entered by the beam and the radial deflections mean the ones corresponded to the X axis which has the same direction of
B
. The maximum longitudinal deviation of bragg pick depth was 0.672 mm at 200 MeV and the maximum radial deflection was almost 4.23 cm at 100 MeV. Both of them are in the presence of
B
= 1.5 T. Our results are in a good agreement with previous experimental results (a maximum relative error founded of 2.08%). The results of this study will offer the monitoring of the dose deposition with good accuracy in the presence of a magnetic field in carbon ion therapy.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The purpose of this work is to determine a date for the next reloading operation of the panoramic gamma irradiator of the Moroccan National Institute of Agronomic Research (NIAR) by studying the ...variation with time of the dosimetric mapping at the inside the irradiation casemate between 2021 and 2030. The NIAR irradiator is a gamma irradiator currently contains 8 cobalt-60 pencils used to develop Moroccan agriculture by doing research in this field by ionization of agricultural products. Monte Carlo simulation via the GEANT4 code was used as a tool to establish the distribution of isodose in the irradiation room due to its important role in meeting the dosimetric requirements for this type of facilities. The results show that from January 1, 2024, serious measures must be taken to arrange a date for the NIAR irradiator reloading operation not later than 2027.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The consequences of radiological accidents outside the nuclear sector can be fatal. Therefore, emergency response plans must take into consideration the worst scenarios. This article presents a ...simulation of an accident in which it was assumed that the assembly of cobalt-60 sources from the irradiator installed at National Institute of Agronomic Research (NIAR) of Tangier was found on the ground. The Monte Carlo GEANT4 code was used to estimate the equivalent dose rate in the organs of an individual presented by an anthropomorphic phantom at different distances, and its variance with decreasing activity, this simulation will allow as to make the best decisions, correct actions, prevent serious radiobiological damage and to prepare the best methods of intervention in the occurrence of this scenario.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Gamma irradiation technology plays a very important role in the development of agriculture, due to its various advantages, such as the inhibition of germination, the appearance of new varieties, ...preservation…etc. To properly control and characterize irradiation operations, the dose rate distribution in the irradiation cells must be well controlled, The Monte-Carlo method was used for experiments the high cost to map the dose rate distribution in the irradiation cell each time, and to its precise dosimetric calculation. In this study the MCNPX code was used to simulate the irradiation cell of the National Institute of Agricultural Research (NIAR) of Tangier Morocco, the validation of the latter was based on a comparative assessment between the dose rates absorbed in the area calculated by MCNPX (Gy/min) and those measured values by alanine dosimeters. The comparative results showed a good agreement between the experiment and the simulation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Due to the shortage of data regarding range and water equivalent ratio (WER), in this work, firstly, depth-dose profiles and range were evaluated in liquid water, Polyethylene (PE), Aluminium, Bone, ...Polymethyl methacrylate (PMMA), and Lead for carbon ion energies ranging 100–300 MeV/n using Fluka Mc code. Afterwards, persuing the repeated use of the above mentioned materials in dosimetric studies in the domain of hadrontherapy, we came up to calculate the water equivalent ratio of only three dosimetric materials (polyethylene (PE), polymethyl methacrylate (PMMA) and lead). Then, we made the remark that the closest and farthest WER values are 1.0016 and 5.7939 respectively, they were obtained for the PE and the lead. The calculated WER values were compared with the values from MCNPX code, and those from the previous analytical methods (NM, BK, BB, EBB). Good agreement was obtained between the results of the MC codes and the previous analytical methods. The largest discrepancy between the two MC codes was 4.2% for PE at 100 MeV/n and was about 1.52% between Fluka and the analytical method (BB) for Lead at 270.83 MeV/n. Among the materials explored, PE stayed the nearest to water with an average WER of 1.0038 for carbon ion energy ranging 100 to 300 MeV/n.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This article, presents an approach to make the cylindrical packaging products in rotation around their fixed axis, in the Monte Carlo simulation during irradiation. This approach will solve the ...rotating plats around its fixed axis problem in the simulation so can be used to improve the dose uniformity and predict the irradiated products packaging form, taking into account its density and its position in the irradiation cell, to save time and the high costs of the experiments. This study has released at Moroccan gamma irradiation station. We have used the MCNPX code to simulate this approach. The validation has been done by an experiment measurement using sugar as a product and alanine dosimeters for dosimetric calculation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The simulation codes based on the monte Carlo method are sophisticated averages and have become essential for dosimetry and radiation protection calculations close to the installations that handle ...radioactive sources. However, before starting to exploit these codes, they must be validated. The aim of this work is to validate two from the Monte Carlo simulation codes most used currently in the world , GEANT4 and MCNP6, for future use in dosimetry and radiation protection requirements in the BOukhalef Ionization Station (SIBO)/ Tangier, Morocco which manipulates a radioactive source of cobalt-60. The validation method is based on a comparison between the simulated results and those obtained by a Fricke system. The codes are well validated, indeed the simulation and experimental results were in good agreement.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Research in the field of foreign language teaching and learning has proved that testing as an assessment instrument is not an adequate means of assessing the multiple dimensions of language learning. ...As a result, various alternative assessment forms have been suggested in the literature to compensate for the weaknesses and limitations of conventional testing and ensure more effective learning. Accordingly, this paper seeks to review the literature on the different forms of alternative assessment that language teachers could use in addition to traditional assessment. More specifically, the present paper aims to explore the types of alternative assessments, stresses their importance by listing the many benefits that these assessment methods proved to have, and also discusses some of their perceived limitations.
The process of learning a language is influenced by a number of factors. One of the most significant factors that has an influence on learning a language is attitude. Research in this area has ...demonstrated that learners’ attitudes are a constituent and crucial part of the learning process. As such, learners’ attitudes towards language should be dealt with as a critical component of second and foreign language learning pedagogy. Accordingly, the current study addresses the attitudes of Moroccan high-school students towards learning English as a foreign language. Specifically, the study aims to investigate Moroccan high-school students’ attitudes towards English, the reasons behind their attitudes and the impacts that such attitudes might potentially have. Generally speaking, the study found that the participants have highly favourable attitudes towards learning English for different reasons, a fact that results in positive impacts on students’ willingness to learn the language.Keywords: Attitudes; Language; EFL context
Language teachers and researchers argue that the process of learning a language is better understood if the errors that language learners make in constructing the new language system are carefully ...analyzed. Hence, analyzing errors has become essential for facing and overcoming problems and suggesting solutions regarding different aspects of language teaching and learning. Accordingly, this study seeks to examine the errors that Moroccan high school students of English make in writing, and investigate the reasons behind the occurrence of such errors. The sample of the study consists of students’ essays collected from different classes. The data collected were analyzed using Corder’s (1967) model, which includes three stages; data collection, description, and explanation. The study’s findings showed that Moroccan EFL students make different types of errors in writing. The most significant number of the errors found in the students’ essays are grammatical errors, and most of these errors are due to intralingual factors.