4,336 research outputs found

    Underlying symmetries of realistic interactions and the nuclear many-body problem

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    The present study brings forward important information, within the framework of spectral distribution theory, about the types of forces that dominate three realistic interactions, CD-Bonn, CDBonn+ 3terms and GXPF1, in nuclei and their ability to account for many-particle effects such as the formation of correlated nucleon pairs and enhanced quadrupole collective modes. Like-particle and proton-neutron isovector pairing correlations are described microscopically by a model interaction with Sp(4) dynamical symmetry, which is extended to include an additional quadrupole-quadrupole interaction. The analysis of the results for the 1f7/2 level shows that both CD-Bonn+3terms and GXPF1 exhibit a well-developed pairing character compared to CD-Bonn, while the latter appears to build up more (less) rotational isovector T = 1 (isoscalar T = 0) collective features. Furthermore, the three realistic interactions are in general found to correlate strongly with the pairing+quadrupole model interaction, especially for the highest possible isospin group of states where the model interaction can be used to provide a reasonable description of the corresponding energy spectra.Comment: 12 pages, 4 figure

    Damage estimation of low to medium rise reinforced concrete buildings considering vertical irregularity

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    In current study, Damage estimation is carried out using new methodology using parameters such as absorbed energy and degrading stiffness by pushover analysis. A new stiffness-based damage index is developed for each increasing step of pushover analysis, which takes into account the cumulative effects of increasing each lateral load and displacement. Non-cumulative absorbed energy-based damage index is calculated using the pushover curve's first maximal hysteretic cycle. These suggested methods can be utilised to quickly calculate the global damage index for low to medium rise vertical irregular buildings. The proposed two methods are evaluated using three regular and vertical irregular buildings considering various parameters such as varying heights, setback orientations, plastic hinges and monotonic loads. Furthermore, existing deformation and strength-based damage indices are used to calibrate the proposed damage indices. Both proposed damage indices may calculate damage index at any point on the pushover curve, however the damage indices are computed at different performance levels. The research based on damage index showed that two approaches for evaluating damage to irregular buildings are easy to use and accurate, Also, using the results of pushover analysis, structural designers may estimate the global damage index as a performance criterion in  short period of time

    Network Intrusion Detection System: Classification, Techniques and Datasets to Implement

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    The Network Intrusion Detection System (NIDS) is a useful security utility that helps to prevent unauthorized and unwanted access to network resources by observing the network traffic and identify the records as either normal or abnormal. In this paper, compare three algorithms for network intrusion detection SVM, KNN and Decision Tree over Dos, Normal, R2L and U2R attacks. The features of SVM dataset are the decline for each type of attacks using correlation-based selection feature method. Then with the reduced feature set, discriminant analysis has done for the classification of different records. Comparison with other techniques shows that modified approach provides good classification rate for Normal, Dos, R2L (Remote-to-Local) and U2R (User-to-Root) attacks. A NIDS can be a software or piece of hardware. Many NIDS tools will store event or log of the event at a later date or will combine events with other data to make decisions about damage control or regarding policies. This paper shows the comparison of the different types of attacks that can be detected in a simulated core network environment. The different types of attacks are normal, DoS, Probe attacks, R2L and U2R attacks. The proposed method is implemented by the Python (Anaconda Navigator) and R programming software and tested on NSL-KDD dataset

    Damage estimation of low to medium rise reinforced concrete buildings considering vertical irregularity

    Get PDF
    In current study, Damage estimation is carried out using new methodology using parameters such as absorbed energy and degrading stiffness by pushover analysis. A new stiffness-based damage index is developed for each increasing step of pushover analysis, which takes into account the cumulative effects of increasing each lateral load and displacement. Non-cumulative absorbed energy-based damage index is calculated using the pushover curve's first maximal hysteretic cycle. These suggested methods can be utilised to quickly calculate the global damage index for low to medium rise vertical irregular buildings. The proposed two methods are evaluated using three regular and vertical irregular buildings considering various parameters such as varying heights, setback orientations, plastic hinges and monotonic loads. Furthermore, existing deformation and strength-based damage indices are used to calibrate the proposed damage indices. Both proposed damage indices may calculate damage index at any point on the pushover curve, however the damage indices are computed at different performance levels. The research based on damage index showed that two approaches for evaluating damage to irregular buildings are easy to use and accurate, Also, using the results of pushover analysis, structural designers may estimate the global damage index as a performance criterion in  short period of time
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