Subjects -> ENERGY (Total: 414 journals)
    - ELECTRICAL ENERGY (12 journals)
    - ENERGY (252 journals)
    - ENERGY: GENERAL (7 journals)
    - NUCLEAR ENERGY (40 journals)
    - PETROLEUM AND GAS (58 journals)
    - RENEWABLE ENERGY (45 journals)

NUCLEAR ENERGY (40 journals)

Showing 1 - 37 of 37 Journals sorted alphabetically
Atom Indonesia     Open Access  
Bulletin of the Atomic Scientists     Hybrid Journal   (Followers: 8)
CNL Nuclear Review     Partially Free  
Eksplorium : Buletin Pusat Pengembangan Bahan Galian Nuklir     Open Access  
EPJ Nuclear Sciences & Technologies     Open Access   (Followers: 3)
Fusion Science and Technology     Hybrid Journal   (Followers: 4)
Ganendra : Majalah IPTEK Nuklir     Open Access  
Hyperfine Interactions     Hybrid Journal   (Followers: 1)
IEEE Transactions on Sustainable Energy     Hybrid Journal   (Followers: 13)
International Journal of Advanced Nuclear Reactor Design and Technology     Open Access  
International Journal of Critical Infrastructure Protection     Hybrid Journal   (Followers: 4)
International Journal of Nuclear Energy Science and Engineering     Open Access   (Followers: 5)
International Journal of Nuclear Law     Hybrid Journal   (Followers: 3)
International Journal of Nuclear Safety and Security     Hybrid Journal   (Followers: 1)
International Journal of Nuclear Security     Open Access   (Followers: 1)
Journal of Nuclear Energy Science & Power Generation Technology     Hybrid Journal   (Followers: 2)
Journal of Nuclear Engineering & Technology     Full-text available via subscription   (Followers: 3)
Journal of Nuclear Science and Technology     Hybrid Journal   (Followers: 2)
Journal of Power Technologies     Open Access   (Followers: 6)
Journal of Radiation Research     Open Access   (Followers: 3)
Journal of the Physical Society of Japan     Hybrid Journal   (Followers: 2)
Kerntechnik     Full-text available via subscription  
Majalah Ilmiah Teknologi Elektro : Journal of Electrical Technology     Open Access   (Followers: 1)
Nano Energy     Open Access   (Followers: 11)
Nanomaterials and Energy     Hybrid Journal   (Followers: 1)
Nuclear Energy and Technology     Open Access   (Followers: 3)
Nuclear Engineering and Technology     Open Access   (Followers: 5)
Nuclear Materials and Energy     Open Access   (Followers: 1)
Nuclear Science and Engineering     Hybrid Journal   (Followers: 7)
Nuclear Science and Techniques     Full-text available via subscription  
Nuclear Technology     Hybrid Journal   (Followers: 5)
Nucleus     Open Access  
Nukleonika     Open Access  
Radiation Detection Technology and Methods     Hybrid Journal   (Followers: 1)
Tri Dasa Mega : Jurnal Teknologi Reaktor Nuklir     Open Access  
Urania Jurnal Ilmiah Daur Bahan Bakar Nuklir     Open Access  
World Journal of Nuclear Science and Technology     Open Access   (Followers: 4)
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Nuclear Science and Techniques
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  Full-text available via subscription Subscription journal
ISSN (Print) 1001-8042 - ISSN (Online) 2210-3147
Published by Springer-Verlag Homepage  [2467 journals]
  • Correction to: Measurement of 134Xe(n,2n) 133m,gXe reaction cross sections
           in 14-MeV region with detailed uncertainty quantification

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      PubDate: 2023-01-18
       
  • Investigation of $$\beta ^-$$ -decay half-life and delayed neutron
           emission with uncertainty analysis

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      Abstract: Abstract \(\beta\) -decay half-life and \(\beta\) -delayed neutron emission ( \(\beta n\) ) are of great importance in the development of basic science and industrial applications, such as nuclear physics and nuclear energy, where \(\beta ^-\) -decay plays an important role. Many theoretical models have been proposed to describe \(\beta\) -decay half-lives, whereas the systematic study of \(\beta n\) is still rare. This study aimed to investigate \(\beta ^-\) -decay half-lives and \(\beta n\) probabilities through analytical formulas and by comparing them with experimental data. Analytical formulas for \(\beta ^-\) -decay properties have been proposed by considering prominent factors, that is, decay energy, odevity, and the shell effect. The bootstrap method was used to simultaneously evaluate the total uncertainty on calculations, which was composed of statistic and systematic uncertainties. \(\beta ^-\) -decay half-lives, \(\beta n\) probabilities, and the corresponding uncertainties were evaluated for the neutron-rich region. The experimental half-lives were well reproduced. Additional predictions are also presented with theoretical uncertainties, which helps to better understand the disparity between the experimental and theoretical results.
      PubDate: 2023-01-18
       
  • Performance of real-time neutron/gamma discrimination methods

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      Abstract: Abstract Nuclear security usually requires the simultaneous detection of neutrons and gamma rays. With the development of crystalline materials in recent years, Cs2LiLaBr6 (CLLB) dual-readout detectors have attracted extensive attention from researchers, where real-time neutron/gamma pulse discrimination is the critical factor among detector performance parameters. This study investigated the discrimination performance of the charge comparison, amplitude comparison, time comparison, and pulse gradient methods and the effects of a Sallen–Key filter on their performance. Experimental results show that the figure of merit (FOM) of all four methods is improved by proper filtering. Among them, the charge comparison method exhibits excellent noise resistance; moreover, it is the most suitable method of real-time discrimination for CLLB detectors. However, its discrimination performance depends on the parameters \({t}_\text{s}\) , \({t}_\text{m}\) , and \({t}_\text{e}\) . When \({t}_\text{s}\) corresponds to the moment at which the pulse is at 10% of its peak value, \({t}_\text{e}\) requires a delay of only 640–740 ns compared to \({t}_\text{s}\) , at which time the potentially optimal FOM of the charge comparison method at 3.1–3.3 MeV is greater than 1.46. The FOM obtained using the \({t}_\text{m}\) value calculated by a proposed maximized discrimination difference model (MDDM) and the potentially optimal FOM differ by less than 3.9%, indicating that the model can provide good guidance for parameter selection in the charge comparison method.
      PubDate: 2023-01-16
       
  • Prediction of synthesis cross sections of new moscovium isotopes in
           fusion-evaporation reactions

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      Abstract: Abstract In the framework of the dinuclear system model, the synthesis mechanism of the superheavy nuclides with atomic numbers \(Z=112, 114, 115\) in the reactions of projectiles \(^{40,48}\) Ca bombarding on targets \(^{238}\) U, \(^{242}\) Pu, and \(^{243}\) Am within a wide interval of incident energy has been investigated systematically. Based on the available experimental excitation functions, the dependence of calculated synthesis cross-sections on collision orientations has been studied thoroughly. The total kinetic energy (TKE) of these collisions with fixed collision orientation shows orientation dependence, which can be used to predict the tendency of kinetic energy diffusion. The TKE is dependent on incident energies, as discussed in this paper. We applied the method based on the Coulomb barrier distribution function in our calculations. This allowed us to approximately consider all the collision orientations from tip-tip to side-side. The calculations of excitation functions of \(^{48}\) Ca + \(^{238}\) U, \(^{48}\) Ca + \(^{242}\) Pu, and \(^{48}\) Ca + \(^{243}\) Am are in good agreement with the available experimental data. The isospin effect of projectiles on production cross-sections of moscovium isotopes and the influence of the entrance channel effect on the synthesis cross-sections of superheavy nuclei are also discussed in this paper. The synthesis cross-section of new moscovium isotopes \(^{278-286}\) Mc was predicted to be as large as hundreds of pb in the fusion-evaporation reactions of \(^{35,37}\) Cl + \(^{248}\) Cf, \(^{38,40}\) Ar + \(^{247}\) Bk, \(^{39,41}\) K + \(^{247}\) Cm, \(^{40,42,44,46}\) Ca + \(^{243}\) Am, \(^{45}\) Sc + \(^{244}\) Pu, and \(^{46,48,50}\) Ti + \(^{237}\) Np, \(^{51}\) V + \(^{238}\) U at some typical excitation energies.
      PubDate: 2023-01-13
       
  • The MING proposal at SHINE: megahertz cavity enhanced X-ray generation

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      Abstract: Abstract The cavity-based X-ray free-electron laser (XFEL) has promise in producing fully coherent pulses with a bandwidth of a few meV and very stable intensity, whereas the currently existing self-amplified spontaneous emission (SASE) XFEL is capable of generating ultra-short pulses with chaotic spectra. In general, a cavity-based XFEL can provide a spectral brightness three orders of magnitude higher than that of the SASE mode, thereby opening a new door for cutting-edge scientific research. With the development of superconducting MHz repetition-rate XFEL facilities such as FLASH, European-XFEL, LCLS-II, and SHINE, practical cavity-based XFEL operations are becoming increasingly achievable. In this study, megahertz cavity enhanced X-ray generation (MING) is proposed based on China’s first hard XFEL facility - SHINE, which we refer to as MING@SHINE.
      PubDate: 2023-01-11
       
  • Measurement of 134Xe(n,2n)133m,gXe reaction cross sections in 14-MeV
           region with detailed uncertainty quantification

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      Abstract: Abstract A lead-shielded HPGe detector and offline γ-ray spectra of the residual product were used to measure the cross section (CS) and ratios of isomeric CS (σm/σg) in 134Xe(n,2n)133m,gXe reactions at different energies (13.5 MeV, 13.8 MeV, 14.1 MeV, 14.4 MeV, 14.8 MeV) relative to the 93Nb(n,2n)92mNb reaction CS. The target was high-purity natural Xe gas under high pressure. The T(d,n)4He reaction produces neutrons. TALYS code (version 1.95) for nuclear reactions was used for calculations, with default parameters and nuclear level density models. The uncertainties in the measured CS data were thoroughly analyzed using the covariance analysis method. The results were compared with theoretical values, evaluation data, and previous experimental findings. CS data of the 134Xe(n,2n)133mXe and 134Xe(n,2n)133gXe reactions and the corresponding isomeric CS ratios at 13.5 MeV, 13.8 MeV, and 14.1 MeV neutron energies are reported for the first time. This research advances our knowledge of pre-equilibrium emission in the (n,2n) reaction channel by resolving inconsistencies in the Xe data.
      PubDate: 2023-01-09
       
  • The complex momentum representation approach and its application to
           low-lying resonances in $${^{17}}$$ O and $${^{29,31}}$$ F

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      Abstract: Abstract Approaches for predicting low-lying resonances, uniformly treating bound, and resonant levels have been a long-standing goal in nuclear theory. Accordingly, we explored the viability of the complex momentum representation (CMR) approach coupled with new potentials. We focus on predicting the energy of the low-lying 2p \(_{3/2}\) resonance in \({^{17}}\) O, which is critical for s-process nucleosynthesis and missing in previous theoretical research. Using a Woods-Saxon potential based on the Koning-Delaroche optical model and constrained by the experimental one-neutron separation energy, we successfully predicted the resonant energy of this level for the first time. Our predictions of the bound levels and 1d \(_{3/2}\) resonance agree well with the measurement results. Additionally, we utilize this approach to study the near-threshold resonances that play a role when forming a two-neutron halo in \({^{29, 31}}\) F. We found that the CMR-based predictions of the bound-level energies and unbound 1f \(_{7/2}\) level agree well with the results obtained using the scattering phase shift method. Subsequently, we successfully found a solution for the 2p \(_{3/2}\) resonance with energy just above the threshold, which is decisive for halo formation.
      PubDate: 2023-01-09
       
  • Efficient extraction of U(VI) ions from solutions

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      Abstract: The rapid development of advanced techniques for selective and efficient U(VI) extraction from aqueous solutions is essential for addressing U(VI) environmental pollution and energy issues. Here, we share recent progress in U(VI) extraction from aqueous solutions, especially the most frequently applied techniques such as adsorption, catalysis (photocatalysis, piezocatalysis, and electrocatalysis), chemical deposition, and reduction by zero-valent metal particles. We attempt to elucidate the strategies and various mechanisms that contribute to the enhancement of selective U(VI) extraction. At the end of our review, we highlight the outlook, challenges, and prospects for the development of this field. Graphical abstract
      PubDate: 2023-01-06
       
  • Large area 3He tube array detector with modular design for multi-physics
           instrument at CSNS

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      Abstract: Abstract The multi-physics instrument (MPI) is the first user cooperative instrument at the China Spallation Neutron Source (CSNS). It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering technique. This imposes the requirements for the detector, including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum transfers. To satisfy these demands, a large-area array of 3He-filled linear position-sensitive detectors (LPSDs) was constructed, each with a diameter of 1 inch and pressure of 20 atm. It uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs, covering a range of scattering angles from 3° to 170° with a total detector area of approximately 7 m2. The detector works in air, which is separated from the vacuum environment to facilitate installation and maintenance. The characteristics of the MPI detector were investigated through Monte Carlo (MC) simulations using Geant4 and experimental measurements. The results suggest that the detectors are highly efficient in the wavelength range of the MPI, and an efficiency over 25% is achievable for above 0.1 Å neutrons. A minimal position resolution of 6.4 mm full width at half maximum (FWHM) along the tube length was achieved at a working voltage of 2200 V, and a deviation below 2 mm between the real and measured positions was attained in the beam experiment. The detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz, which satisfied the requirements of experiments with a high event rate. Observations of its operation over the past year have shown that the detector works steadily in sample experiments, which allows the MPI to serve the user program successfully.
      PubDate: 2023-01-06
       
  • Conceptual design of a Cs2LiLaBr6 scintillator-based neutron total cross
           section spectrometer on the back-n beam line at CSNS

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      Abstract: Abstract To reduce the experimental uncertainty in the \(^{235}\) U resonance energy region and improve the detection efficiency for neutron total cross section measurements compared with those obtained with the neutron total cross section spectrometer (NTOX), a dedicated lithium-containing scintillation detector has been developed on the Back-n beam line at the China Spallation Neutron Source. The Fast Scintillator-based Neutron Total Cross Section (FAST) spectrometer has been designed based on a Cs \(_{2}\) LiLaBr \(_{6}\) (CLLB) scintillator considering the \(\gamma\) -ray flash and neutron environment on the Back-n beam line. The response of the CLLB scintillator to neutrons and \(\gamma\) -rays was evaluated with different \(^6\) Li/ \(^7\) Li abundance ratios using Geant4. The neutron- \(\gamma\) discrimination performance of the CLLB has been simulated considering different scintillation parameters, physical designs, and light readout modes. A cubic \(^6\) Li-enriched ( \(>90\%\) ) CLLB scintillator, which has a thickness of 4-9 mm and side length of no less than 50 mm to cover the \(\Phi\) 50 mm neutron beam at the spectrometer position, has been proposed coupling to a side readout SiPM array to construct the FAST spectrometer. The developed simulation techniques for neutron- \(\gamma\) discrimination performance could provide technical support for other neutron-induced reaction measurements on the Back-n beam line.
      PubDate: 2023-01-06
       
  • Evaluating the JEFF 3.1, ENDF/B-VII.0, JENDL 3.3, and JENDL 4.0 nuclear
           data libraries for a small 100 MWe molten salt reactor with plutonium
           fuel

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      Abstract: Abstract This study evaluated the nuclear data libraries for a small 100 Mega Watt electric (MWe) Molten Salt Reactor with plutonium fuel. The reactor has a power output of 100 MWe, which meets the demand for electricity generation in several regions or provinces outside Java Island. Several nuclear data libraries, such as JEFF 3.1, ENDF/B-VII.0, JENDL 3.3, and JENDL 4.0, were used for a more comprehensive evaluation. LiF–BeF2–ThF4–PuF4 was used as the initial fuel composition. The thorium and plutonium concentrations in the fuel salt were varied to obtain the optimum fuel composition, leading to critical conditions. The results showed some neutronic parameters, such as the conversion ratio, neutron spectra, and effective multiplication factors, from three different nuclear data libraries. By changing the plutonium concentration in the initial fuel salt composition, the minimum plutonium loaded for the reactor criticality during 2000 days of operation time was determined to be 0.995, 0.91, 0.87, and 0.90 mol% for JEFF 3.1, ENDF/B-VII.0, JENDL 3.3, and JENDL 4.0, respectively. The differences in the values of each parameter were due to several factors, such as the cross-section values and number of nuclides in the nuclear data libraries. Several safety parameters were also investigated to ensure the possibility of utilizing PuF4 in the reactor.
      PubDate: 2022-12-16
       
  • Comparison of neutron energy spectrum unfolding methods and evaluation of
           rationality criteria

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      Abstract: Abstract The neutron energy spectrum was measured using a Bonner sphere spectrometer at six locations inside the containment vessel of a nuclear reactor at the Qinshan nuclear power plant. The structures of the neutron spectra obtained by the maximum entropy, iteration, and genetic algorithm methods were consistent with one another and could be interpreted as the spectral superposition of different energy regions. The characteristic parameters of the neutron spectrum, including the fluence rate, average energy, and neutron ambient dose equivalent rate \(\dot{H}^{*}\) (10), were in good agreement among the three methods. In addition, an LB6411 neutron ambient dose equivalent meter was employed to obtain the \(\dot{H}^{*}\) (10) directly for comparison. These findings indicate that neutron spectrum unfolding methods can be used to overcome the problems associated with the response functions of dosimeters to provide more accurate \(\dot{H}^{*}\) (10) values. In this study, the following three evaluation criteria were systematically addressed to ensure the accuracy of the unfolded spectra: count rates of the inverse solutions, neutron spectrum structures, and comparison of key parameters.
      PubDate: 2022-12-13
       
  • Effects of the momentum dependence of nuclear symmetry potential on pion
           observables in Sn + Sn collisions at 270 MeV/nucleon

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      Abstract: Abstract Within a transport model, we investigated the effects of the momentum dependence of the nuclear symmetry potential on the pion observables in central Sn + Sn collisions at 270 MeV/nucleon. To this end, the quantity \(U_\text {sym}^{\infty }(\rho _{0})\) (i.e., the value of the nuclear symmetry potential at the saturation density \(\rho _{0}\) and infinitely large nucleon momentum) was used to characterize the momentum dependence of the nuclear symmetry potential. With a certain L (i.e., the slope of the nuclear symmetry energy at \(\rho _{0}\) ), the characteristic parameter \(U_\text {sym}^{\infty }(\rho _{0})\) of the symmetry potential significantly affects the production of \(\pi ^{-}\) and \(\pi ^{+}\) and their pion ratios. Moreover, by comparing the charged pion yields, pion ratios, and spectral pion ratios of the theoretical simulations for the reactions \(^{108}\) Sn + \(^{112}\) Sn and \(^{132}\) Sn + \(^{124}\) Sn with the corresponding data in the S \(\pi \) RIT experiments, we found that our results favor a constraint on \(U_\text {sym}^{\infty }(\rho _{0})\) (i.e., \(-160^{+18}_{-9}\)  MeV), and L is also suggested within a range of 62.7 MeV \(<L<93.1\)  MeV. In addition, the pion observable for \(^{197}\) Au + \(^{197}\) Au collisions at 400 MeV/nucleon also supports the extracted value for \(U_\text {sym}^{\infty }(\rho _{0})\) .
      PubDate: 2022-12-12
       
  • An FPGA-based trigger system for CSHINE

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      Abstract: Abstract A trigger system of the general function was designed using the commercial module of CAEN V2495 for heavy-ion nuclear reaction experiments at Fermi energies. The system was applied and verified on the compact spectrometer for heavy IoN experiment (CSHINE). Based on the field-programmable logic gate array technology of the command register access and remote computer control operation, trigger functions can be flexibly configured according to experimental physical goals. Using the trigger system on CSHINE, we conducted a beam experiment at 25 MeV/u \(^{86}\textrm{Kr}+ ^{124}\textrm{Sn}\) on the Radioactive Ion Beam Line 1 in Lanzhou, China. The online results demonstrated that the trigger system worked normally and correctly. This system can be extended to other experiments as well.
      PubDate: 2022-12-09
       
  • Heavy ion-induced MCUs in 28 nm SRAM-based FPGAs: upset proportions,
           classifications, and pattern shapes

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      Abstract: Abstract For modern scaling devices, multiple cell upsets (MCUs) have become a major threat to high-reliability field-programmable gate array (FPGA)-based systems. Thus, both performing the worst-case irradiation tests to provide the actual MCU response of devices and proposing an effective MCU distinction method are urgently needed. In this study, high- and medium-energy heavy-ion irradiations for the configuration random-access memory of 28 nm FPGAs are performed. An MCU extraction method supported by theoretical predictions is proposed to study the MCU sizes, shapes, and frequencies in detail. Based on the extraction method, the different percentages, and orientations of the large MCUs in both the azimuth and zenith directions determine the worse irradiation response of the FPGAs. The extracted largest 9-bit MCUs indicate that high-energy heavy ions can induce more severe failures than medium-energy ones. The results show that both the use of high-energy heavy ions during MCU evaluations and effective protection for the application of high-density 28 nm FPGAs in space are extremely necessary.
      PubDate: 2022-12-09
       
  • Gaussian shaper for nuclear pulses based on multilevel cascade convolution

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      Abstract: Abstract For nuclear measurements, it is necessary to obtain accurate information from nuclear pulses, which should be obtained by first shaping the pulses outputted by the detectors. However, commonly used pulse-shaping algorithms have certain problems. For example, certain pulse-shaping algorithms have long dead-times in high-counting-rate environments or are difficult to achieve in digital systems. Gaussian signals are widely used in analog nuclear instruments owing to their symmetry and completeness. A Gaussian signal is usually implemented by using a multilevel S–K filter in series or in parallel. It is difficult to construct a real-time digital Gaussian filter for the complex Gaussian filtering algorithm. Based on the multilevel cascade convolution, a pulse-shaping algorithm for double exponential signals is proposed in this study, which, in addition to double exponential signals, allows more complex output signal models to be used in the new algorithm. The proposed algorithm can be used in high-counting-rate environments and has been implemented in an FPGA with fewer multipliers than those required in other traditional Gaussian pulse-shaping algorithms. The offline processing results indicated that the average peak base width of the output-shaped pulses obtained using the proposed algorithm was reduced compared with that obtained using the traditional Gaussian pulse-shaping algorithm. Experimental results also demonstrated that signal-to-noise ratios and energy resolutions were improved, particularly for pulses with a low energy. The energy resolution was improved by 0.1–0.2% while improving the counting rate.
      PubDate: 2022-12-09
       
  • Discrimination of neutron and gamma ray using the ladder gradient method
           and analysis of filter adaptability

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      Abstract: Abstract This study proposes a ladder gradient method for neutron and gamma-ray discrimination. The proposed method exhibited state-of-the-art performance with low time consumption, which incorporates two parts: information extraction and discrimination factor calculation. A quasi-continuous spiking cortical model was proposed to extract information from the radiation pulse signals, thus generating an ignition map corresponding to each pulse signal. The ignition map can be used to calculate the discrimination factor. A ladder gradient calculation was introduced to obtain a discrimination factor with low computational complexity. The proposed method was compared with five other discrimination methods to evaluate its robustness and efficacy. Furthermore, the filter adaptability of the pulse-coupled neural network and ladder gradient methods was investigated. Possible reasons for adapting the conditions with different discrimination methods and filters were analyzed. Experiments were conducted in 20 filtering situations with 11 types of filters to determine the most suitable filters for discrimination methods. The experimental results revealed that the three most adaptive filters of the pulse-coupled neural networks and ladder gradient methods are the wavelet, elliptic, and median filters and the elliptic, moving average, and wavelet filters, respectively.
      PubDate: 2022-12-09
       
  • A novel approach for feature extraction from a gamma-ray energy spectrum
           based on image descriptor transferring for radionuclide identification

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      Abstract: Abstract This study proposes a novel feature extraction approach for radionuclide identification to increase the precision of identification of the gamma-ray energy spectrum set. For easier utilization of the information contained in the spectra, the vectors of the gamma-ray energy spectra from Euclidean space, which are fingerprints of the different types of radionuclides, were mapped to matrices in the Banach space. Subsequently, to make the spectra in matrix form easier to apply to image-based deep learning frameworks, the matrices of the gamma-ray energy spectra were mapped to images in the RGB color space. A deep convolutional neural network (DCNN) model was constructed and trained on the ImageNet dataset. The mapped gamma-ray energy spectrum images were applied as inputs to the DCNN model, and the corresponding outputs of the convolution layers and fully connected layers were transferred as descriptors of the images to construct a new classification model for radionuclide identification. The transferred image descriptors consist of global and local features, where the activation vectors of fully connected layers are global features, and activations from convolution layers are local features. A series of comparative experiments between the transferred image descriptors, peak information, features extracted by the histogram of the oriented gradients (HOG), and scale-invariant feature transform (SIFT) using both synthetic and measured data were applied to 11 classical classifiers. The results demonstrate that although the gamma-ray energy spectrum images are completely unfamiliar to the DCNN model and have not been used in the pre-training process, the transferred image descriptors achieved good classification results. The global features have strong semantic information, which achieves an average accuracy of 92.76% and 94.86% on the synthetic dataset and measured dataset, respectively. The results of the statistical comparison of features demonstrate that the proposed approach outperforms the peak-searching-based method, HOG, and SIFT on the synthetic and measured datasets.
      PubDate: 2022-12-08
       
  • Multiple-models predictions for drip line nuclides in projectile
           fragmentation of $$^{40,48}$$ Ca, $$^{58,64}$$ Ni, and $$^{78,86}$$ Kr at
           140 MeV/u

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      Abstract: Abstract Modern rare isotope beam (RIB) factories will significantly enhance the production of extremely rare isotopes (ERI) at or near drip lines. As one of the most important methods employed in RIB factories, the production of ERIs in projectile fragmentation reactions should be theoretically improved to provide better guidance for experimental research. The cross-sections of ERIs produced in 140 MeV/u \(^{78,86}\) Kr/ \(^{58,64}\) Ni/ \(^{40,48}\) Ca + \(^{9}\) Be projectile fragmentation reactions were predicted using the newly proposed models [i.e., Bayesian neural network (BNN), BNN + FRACS, and FRACS, see Chin. Phys. C, 46: 074104 (2022)] and the frequently used EPAX3 model. With a minimum cross-section of \(10^{-15}\) mb, the possibilities of ERIs discovery in a new facility for rare isotope beams (FRIB) are discussed.
      PubDate: 2022-12-07
       
  • Two-parameter dynamical scaling analysis of single-phase natural
           

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      Abstract: Abstract Scaling analysis is widely used to design scaled-down experimental facilities through which the prototype phenomena can be effectively evaluated. As a new method, dynamic system scaling (DSS) must be verified as a rational and applicable method. A DSS method based on dilation transformation was evaluated using single-phase natural circulation in a simple rectangular loop. The scaled-down cases were constructed based on two parameters—length ratio and dilation number—and the corresponding transient processes were simulated using the Relap5 computational code. The results show that this DSS method can simulate the dynamic flow characteristics of scaled-down cases. The transient deviation of the temperature difference and mass flow rate of the scaled cases decrease with increases in the length ratio and dilation number. The distortion of the transient temperature difference is smaller than that of the mass flow; however, the overall deviation is within a reasonable range.
      PubDate: 2022-12-07
       
 
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