Atom Indonesia (E-Journal)
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Voice Classification Based on Fast Independent Component Analysis to Support Nuclear Power Plant Security
Get PDFNational vital objects have important role in national development,so they require special protection. Nuclear power plant (NPP) is one of them. Access restriction is required to prevent the NPP from potential hazards. The restriction can be improved by using face, fingerprints, retina, iris, and voice password. The improvement will enhance the security of the NPP. This research has implemented pattern recognition and classification of voice passwords. The passwords were a, i, u, e, and o. The features vector was searched by using Fast ICA method while the pattern classification was performed by minimum Euclidean method. The purpose of this research is to recognize and classify those letter password, so people who have access to the nuclear area can be distinguished. The methodology of this research consists of input data, pre-processing data, feature extraction, and classification. Pre-processing was done by normalization, denoising, centering, and whitening. Feature extraction was performed by Fast ICA method, and classification was done by minimum Euclidean distance. The results show that Fast ICA and minimum Euclidean methods can 100 % distinguish between the employees who have access permit and those who have no access permit. When an employee with access permit says "aiueo”, it will be recognized as password, whereas when an employee with no access permit says the password, it will be recognized not as the password
Safety Analysis of the TRIGA 2000 U3Si2-Al Fuel Core Under Reactivity Insertion Accidents
Get PDFTheTRIGA 2000 reactor in Bandung is planned to change its fuel type from the TRIGA fuel rod type to the U3Si2-Al plate type of low enriched uranium of 19.75 % with uranium density of 2.96 gU/cc. A study on the neutronic parameters from the equilibrium core has been done. To ensure safe operation of the new fuel, thermodynamic evaluation of the core needs to be done. The purpose of this study is to conduct a reactor safety analysis of reactivity insertion during withdrawal of the control rod and to study the effect of this reactivity insertion on the power and the maximum temperature of the fuel and the cladding. Reactivity insertion accident is the main factor of the design basis accidents in nuclear reactor design. A simulation of transient for reactivity insertion has been carried out using a coupled neutronic and thermal-hydraulic MTR-DYN code. The code was developed based on three-dimensional multigroup neutron diffusion theory. The coupled space and time-dependent problem were solved by adiabatic model. Transient analysis was performed for a reactivity insertion of 32.33 pcm/s with the assumption that all of the control rods were rapidly withdrawn. For the insertion at a low power of 100 W, the maximum power achieved was 2.74 MW while a maximum power of 2.3 MW was achieved for the power transient of 1 MW. The maximum temperature of the coolant, the cladding, and the fuel for TRIGA 2000 core does not exceed the allowable safety limit for reactivity insertions
Natural Radionuclides Determination and Radiological Hazard Assessments in Soil from Tual and Kei Islands, Indonesia
Get PDFNatural radionuclides 226Ra, 232Th and 40K in soil are the primary component of the background exposure sources of the population. Study of the external exposure due to gamma-ray radiation of natural radionuclides is important because this may contribute significantly to the total annual individual dose. The purpose of this study is to investigate the natural radionuclides in soils collected from Tual and Kei islands and assess the radiological hazard due to natural radionuclides contents in soil. The soil samples were analyzed for natural radionuclides 226Ra, 232Th and 40K using gamma ray spectrometry. Radiological hazard parameters were estimated from the activity concentration of these radionuclides in order to assess health implication of exposure of the general public. The activity concentrations of 226Ra, 232Th and 40K in soil samples varied from 7.50 Bq kg-1 to 6326 Bq kg-1, 0.99 Bq kg-1 to 157 Bq kg-1, 2.97 kg-1to 98.91 Bq kg-1 with the average value of 2162 Bq kg-1; 69.68 Bq kg-1 and 30.74 Bq kg-1, respectively. The absorbed dose rates due to the presence of 226Ra, 232Th and 40K, in soil samples in the studied area vary between the range of 4.88 nGy h-1 and 3018.80 nGy h-1 with the average value of 1042 nGy h-1. The corresponding outdoor annual effective doses ranged between 0.01 mSv y-1 and 3.70 mSv y-1 with the average value of 1.28 mSv y-1. Radium equivalent activities are calculated to be in the range of 10.42 Bq kg-1 -6553.03 Bq kg-1 with the average value of 2264 Bq kg-1.The external and internal hazard indexes vary from 0.03 to 17.71 with the average value of 6.12 and 0.05 to 34.81 with the average value of 11.96, respectively. All calculated average radiological hazard indices were higher than the limits recommended for individual members of the public
Effect of Garlic, Stinky Bean, Dogfruit, Tomato Extracts, and N-acetylcysteine on Rats after 5 Gy Irradiation
Get PDFThe formation of reactive oxygen species (ROS) and free radicals is the most important effect of radiation exposure on biological systems. Several studies have shown that several vegetables are proven to have beneficial effects to protect the body from free radical attacks. This current study was focused on exploring the capability of extracts of garlic, stinky bean, dog fruit, and tomato, as well as N-acetylcystein (NAC), in counteracting free radicals induced by gamma irradiation with a dose of 5 Gy. Seven treatments on male rat were as follow: A (control), B (5 Gy), C (garlic + 5 Gy), D (stinky bean + 5 Gy), E (dogfruit + 5 Gy), F (tomato + 5 Gy) andG (NAC + 5 Gy). The rats were irradiated 8 days after the supplement had been given. Detection of malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), and 8-hydroxy-2-deoxyguanosine (8-OHdG) was done by biochemical assays, and γ-H2AX foci were counted by immunofluorescence assay to the lymphocytes and plasma samples. The results showed that gamma irradiation with a dose of 5 Gy caused increases in the level of MDA, 8-OHdG, and γ-H2AX foci while decreases were recorded in the level of GSH, GPx, and CAT (p 0.05). The treatment of garlic, dogfruit, and tomato extracts and NAC reduced free radicals significantly. In conclusion, the tomato has the best ability to overcome free radicals due to gamma irradiation among the treatments inthe experiment
Molecular and in silico Study of TP53 Codon 72 Polymorphism (rs1042522) in a Population Exposed to High Background Radiation in Mamuju-West Sulawesi
Get PDFThe evaluation of the tumor protein p53 (TP53) codon 72 polymorphism (rs1042522) status in a population exposed to high background radiation was performed in this study. Real-time polymerase chain reaction (Q-PCR) was used to genotype the rs1042522 polymorphism in 100 subjects from Takandeang, Salleto, and Ahu villages in Mamuju district, West Sulawesi. An in silico study was then conducted to identify the potential effects of the proline substitution associated with this polymorphism on protein stability. The in silico analysis was performed using three different computational tools, namely I-Mutant Suite, iStable, and Protein Variation Effect Analyzer (PROVEAN). Secondary and three-dimensional (3D) structural models for wild-type (WT) and variant TP53 were generated to predict potential structural changes in the protein. Electrostatic surface charge calculations were also performed to identify changes in the electrostatic charge of codon 72. The Pro72 and Arg72 frequencies among the inhabitants in the Takandeang, Salleto, and Ahu villages, who are Mandarese Austronesian-speaking ethnic group members, were 0.56 and 0.44, respectively. The in silico analysis revealed no negative effects on protein stability due to the proline substitution at codon 72, although molecular modeling showed several differences in the secondary and 3D structures of the TP53 variant compared with the structure of WT TP53. To determine the impact of the proline-coding allele on individual sensitivity to radiation exposure, we compared the micronucleus (MN) frequencies of each genotype. The results showed that the MN frequencies in individuals harboring the proline-coding allele were not significantly higher than those expressing the arginine-coding allele. In conclusion, this study revealed that the proline-coding allele for codon 72 of the TP53 gene represented the predominant genotype among Takandeang, Salleto, and Ahu villages inhabitants. The present study also demonstrated that individuals who carried the proline-coding allele were not more sensitive to radiation compared with those expressing the arginine-coding allele for codon 72 of the TP53 gene
Effect of Ion Irradiation on the Mechanical Properties of High and Low Copper
Get PDFAn investigation into the effects of proton beam exposure on high- and low-copper structural materials for nuclear reactors has been carried out. The aim of this work was to investigate the impact of proton energy irradiation on the damage of the materials. The damage parameter used in the evaluation was displacement per atom (dpa) in material as a function of proton energy. In addition, a TRIM code was used to identify the penetration depth in response to changes in proton energy. The effect of proton beam exposure on the irradiation induced hardening of the different copper levels was investigated by Vickers Hardness tests for microstructural changes examination. The proton beam incident energy was 3 MeV and the temperature was kept at approximately 30 ᴼC. A 25 μm flat damage profile was achieved at 0.367 and 0.373 dpa for low and high copper samples, respectively. The hardness variation with depth and yield strength variation with dose (dpa) were also investigated. Based on the results, the study found that the hardness test for the high copper was higher than the low copper
Effects of Gamma Irradiation on Mating Competitiveness of Male Culex quinquefasciatus (Diptera:Culicidae) in Laboratory
Get PDFCulex quinquefasciatus is the main vector of lymphatic filariasis in Pekalongan City. Sterile Insect Technique (SIT) can be employed as complementary vector control for filariasis. The key success of this technique depends on the ability of laboratory-reared sterile males to mate with the wild-type females. This research aimed to was to determine the mating competitiveness, fecundity and fertility of sterile males of Cx. quinquefasciatus. The pupae of Cx. quinquefasciatus were gamma irradiated at doses of 60, 70, and 80 Gy, whereas unirradiated pupae were prepared as control. The mosquitoes emerging from the irradiated pupae were found to be able to mate with normal females in the cages. Observation was done for the mean female laying eggs, the fecundity, the fertility and the mating competitiveness. The observation data were analyzed by one-way ANOVA. The results show that the irradiated Cx. quinquefasciatus at the test doses does not affect the fecundity and the mating competitiveness, but the fertility is disturbed (sterile). A dose of 70 Gy was found to be the optimum dose, which gave a fertility rate of 1.8 % (98.2 % sterile) with a value of competitiveness (C index) of 0.568. Based on these results, irradiated Cx. quinquefasciatus can be recommended for semifield application