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[en] Highlights: • Review of the requirements and recommendations for BEPU methodology. • Summary of the advantages and limitations of the current deterministic bounding method for non-LOCA transient analysis. • Description of a pragmatic, graded approach for application of the BEPU methodology to non-LOCA transient analysis. • Proposal for a demonstration case. - Abstract: Since 1990’s, the use of best estimate plus uncertainty (BEPU) methodology is becoming a common practice for large-break Loss-Of-Coolant Accident (LOCA) analysis. However, the development and application of BEPU methodology requires a higher-level requirement on the verification and validation, and uncertainty quantification (VVUQ) of the used calculational method and computer codes. This may result in a high-cost for BEPU methodology development, and hence prevent the industry to take full benefit from the BEPU applications. This paper proposes a pragmatic, graded approach for application of the BEPU methodology to non-LOCA transient analyses.
[en] This paper presents an overview of modelling features of the first revision of the V2.1 major version of the European severe accident integral code ASTEC which has been set-up by IRSN and delivered to the ASTEC worldwide community end of 2016. After some generalities concerning the software structure and the packaging of ASTEC V2.1 revision 1, the phenomena addressed by the different modules constitutive of ASTEC are detailed. Finally, perspectives as concerns the development of future versions of ASTEC V2.1 at IRSN are outlined. (author)
[en] Green behavior is an important part of the study of green development. To promote green development, it is necessary to engage in further innovation on the basis of lessons from international advancements in green behavior. To clarify the spatial and temporal distribution characteristics of international researchers in the study of green behavior, the research focus, and the research frontiers, a visual analysis was performed on 22,114 articles cited in the SSCI and SCI-EXPANDED databases from 2000 to 2017. This analysis was based on bibliometrics and mapping knowledge domain (MKD) analysis with CiteSpace 5.3.R4, a scientific and technological text-mining and visualization software. The results show that international green behavior research has the following main characteristics. First, a positive correlation was found between the number of papers and time. Second, research is highly valued by researchers in the natural sciences, such as ecology. The USA is involved in major research efforts and maintains a high level of cooperation with other countries and regions. International cooperation among institutions needs to be strengthened. The co-cited journals are primarily academic journals in the natural sciences. Third, research hotspots mainly focus on the theory of planned behavior (TPB), consumers, attitudes, performance, and environment, all of which evolve according to the phase path of “germination-growth.” Fourth, the research frontier issues are largely related to management science and environmental science, and the research objects and methods will become increasingly complex and interdisciplinary over time.
[en] We have derived a straightforward and flexible analytical formula to calculate the electronic transmission of a system with a single impurity. Furthermore, two easy-to-follow subderived examples combined with two corresponding FORTRAN codes have been clearly presented. The formula can be employed for more sophisticated systems owing to the allocation of specific parameters, namely onsite energy and coupling elements, for the corresponding part of the system, such as left lead, impurity, and right lead. Moreover, the formula is well defined so that it can easily be formulated with other programming languages such as C++ or Python. We believe that the current work would greatly help new students and researchers in the field of molecular electronics. (paper)
[en] Elemental compositions are commonly determined from the exact m/z of the monoisotopic peak, which is often the lightest isotope. However, the lightest isotope peak is often weak or absent and the monoisotopic peak can be difficult to identify for organometallics, polyhalogenated compounds, or large molecules. An alternative approach using the abundant isotope for elemental composition determinations is presented here. .
[en] Over the last decade, various machine learning (ML) and statistical approaches for protein–protein interaction (PPI) predictions have been developed to help annotating functional interactions among proteins, essential for our system-level understanding of life. Efficient ML approaches require informative and non-redundant features. In this paper, we introduce novel types of expert-crafted sequence, evolutionary and graph features and apply automatic feature engineering to further expand feature space to improve predictive modeling. The two-step automatic feature-engineering process encompasses the hybrid method for feature generation and unsupervised feature selection, followed by supervised feature selection through a genetic algorithm (GA). The optimization of both steps allows the feature-engineering procedure to operate on a large transformed feature space with no considerable computational cost and to efficiently provide newly engineered features. Based on GA and correlation filtering, we developed a stacking algorithm GA-STACK for automatic ensembling of different ML algorithms to improve prediction performance. We introduced a unified method, HP-GAS, for the prediction of human PPIs, which incorporates GA-STACK and rests on both expert-crafted and 40% of newly engineered features. The extensive cross validation and comparison with the state-of-the-art methods showed that HP-GAS represents currently the most efficient method for proteome-wide forecasting of protein interactions, with prediction efficacy of 0.93 AUC and 0.85 accuracy. We implemented the HP-GAS method as a free standalone application which is a time-efficient and easy-to-use tool. HP-GAS software with supplementary data can be downloaded from: http://www.vinca.rs/180/tools/HP-GAS.php. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature.
[en] In this paper, an analysis of the spread of random extraneous low-frequency (50 Hz) vibrations excited in a gravimeter body is presented. Further, their influence on the gravimeter scale reference system is determined by applying the theory of covariance function. The data on the measurement of strength of random extraneous vibrations in fixed points excited in the gravimeter body were recorded on the time scale in the form of arrays using a three-axis accelerometer. High-frequency (2 and 20 kHz) noise vibrations were also used to modulate the gravimeter scale data. While processing the results of measuring the strength of random extraneous vibrations and the data arrays on the reference system, estimates of autocovariance and cross-covariance functions by changing the quantisation interval on the time scale were calculated. Software developed within the MATLAB 7 package was applied for the calculations. (author)
[en] This paper reports the printability and thermo-mechanical investigations of poly-lactic acid-polyether ketone-ketone- hydroxyapatite-chitosan (PLA-PEKK-HAp-CS) based functional prototypes printed with commercial fused deposition modelling (FDM) setup (without any alteration in software/hardware configuration). The in-house prepared feed stock filament comprising of PLA-PEKK-HAp-CS was used to print flexural samples as per ASTM D790. The samples prepared were investigated for flexural strength (on universal tensile testing (UTM) setup), thermal stability (on differential scanning calorimeter (DSC) setup) followed by morphological analysis (based upon metallurgical image analysis software for porosity evaluation as per ASTM B276). The results of study suggest that from flexural strength viewpoint for PLA-PEKK-HAp-CS based functional prototypes: infill density/percentage followed by infill speed is significant printing parameter. The predicted maximum flexural strength (26.3 MPa) and experimental results (26.17 MPa) are in line to each other and results are valid at 95% confidence level. The best settings of FDM printer from peak strength view point are 100% infill density/percentage, 50 mm s−1 infill speed and 4 no. of perimeters. Further in present case study it has been observed that samples prepared with low infill percentage posses better thermal stability and modulus of toughness as compared to samples prepared with high infill percentage. (paper)
[en] Chaos-based true random bit generators have been demonstrated in many studies to be feasible and secure for crypto-system applications. In this work, we demonstrate that an FPGA-based non-autonomous chaotic oscillator, used as a true random number generator, can be compromised via cryptanalysis attacks. First, we realize non-autonomous chaotic oscillator (previously implemented only in analog form) on a modular FPGA platform. The oscillator architecture is simplified to eliminate the Sin function and is described in details in VHDL. Then, we propose chaotic oscillator attacking system including clock glitch generator to compromise the oscillator by injecting glitches on function clock. The parameters and positions of those glitches are carefully determined to achieve a successful attack. The experimental results show that the system is attacked, and the generated glitched bit-streams are distorted, unlike the bit-streams generated without glitching. The randomness of the generated bit-streams is checked using the NIST test tool.