Pub Date : 2024-08-20DOI: 10.1016/j.net.2024.08.038
Jaeseok Yoo, Young-jin Oh, Nam-hyun Kim, Soo-ill Lee, Jaepil Ko
As the proportion of renewable energy has increased in the national power grid of Republic of Korea, various efforts are needed to maintain the stability of total power generation. All kinds of power plants, including nuclear power, must notify the grid operation organization of their expected transmission power. Even in NPPs, the accuracy of transmission power forecasting can increase the plant owner's economic benefits as well as the stability of the power grid. The transmission power of a NPP is affected by various plant conditions and environmental conditions, including the temperature of circulating water (sea water). In this study, we explored how to effectively handle the long-term dependence problem and various data characteristics to increase the forecasting accuracy of transmission power in NPPs by introducing a Seq2Seq model with an encoder-decoder structure and an attention mechanism, beyond traditional time series deep learning models, especially LSTM. This approach will improve the accuracy of transmission power forecasting and contribute to a stable power supply. Additionally, the model is expected to provide a realistic and practical solution for the power demand response of power plants.
{"title":"Multi-step multivariate forecasting of transmission power in NPPs using operational and meteorological data","authors":"Jaeseok Yoo, Young-jin Oh, Nam-hyun Kim, Soo-ill Lee, Jaepil Ko","doi":"10.1016/j.net.2024.08.038","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.038","url":null,"abstract":"As the proportion of renewable energy has increased in the national power grid of Republic of Korea, various efforts are needed to maintain the stability of total power generation. All kinds of power plants, including nuclear power, must notify the grid operation organization of their expected transmission power. Even in NPPs, the accuracy of transmission power forecasting can increase the plant owner's economic benefits as well as the stability of the power grid. The transmission power of a NPP is affected by various plant conditions and environmental conditions, including the temperature of circulating water (sea water). In this study, we explored how to effectively handle the long-term dependence problem and various data characteristics to increase the forecasting accuracy of transmission power in NPPs by introducing a Seq2Seq model with an encoder-decoder structure and an attention mechanism, beyond traditional time series deep learning models, especially LSTM. This approach will improve the accuracy of transmission power forecasting and contribute to a stable power supply. Additionally, the model is expected to provide a realistic and practical solution for the power demand response of power plants.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"71 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-19DOI: 10.1016/j.net.2024.08.033
P. Martinez-Reviriego, N. Fuster-Martínez, D. Esperante, M. Boronat, B. Gimeno, C. Blanch, D. González-Iglesias, P. Martín-Luna, E. Martínez, A. Menendez, L. Pedraza, J. Fernández, J. Fuster, A. Grudiev, N. Catalan Lasheras, W. Wuensch
High-Gradient accelerating cavities are one of the main research lines in the development of compact linear accelerators. However, the operation of such accelerating cavities is currently limited by non-linear electromagnetic effects that are intensified at high electric fields, such as RF breakdowns, dark currents and radiation. A novel normal-conducting High Gradient S-band Backward Travelling Wave accelerating cavity for medical application (v = 0.38c) has been designed and constructed at CERN with a design gradient of 50 MV/m. In this paper, the high-power performance studies of this novel design carried out at the IFIC high-power laboratory are presented, as well as the analysis of the conditioning parameters in combination with numerical simulations.
高梯度加速腔是开发紧凑型直线加速器的主要研究方向之一。然而，这种加速腔的运行目前受到非线性电磁效应的限制，这些效应在高电场下会加剧，如射频击穿、暗电流和辐射。欧洲核子研究中心（CERN）设计并建造了一个用于医疗应用的新型常导高梯度 S 波段后向游波加速腔（v = 0.38c），其设计梯度为 50 MV/m。本文介绍了在 IFIC 高功率实验室对这种新型设计进行的高功率性能研究，以及结合数值模拟对调节参数进行的分析。
{"title":"High-power performance studies of an S-band high-gradient accelerating cavity for medical applications","authors":"P. Martinez-Reviriego, N. Fuster-Martínez, D. Esperante, M. Boronat, B. Gimeno, C. Blanch, D. González-Iglesias, P. Martín-Luna, E. Martínez, A. Menendez, L. Pedraza, J. Fernández, J. Fuster, A. Grudiev, N. Catalan Lasheras, W. Wuensch","doi":"10.1016/j.net.2024.08.033","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.033","url":null,"abstract":"High-Gradient accelerating cavities are one of the main research lines in the development of compact linear accelerators. However, the operation of such accelerating cavities is currently limited by non-linear electromagnetic effects that are intensified at high electric fields, such as RF breakdowns, dark currents and radiation. A novel normal-conducting High Gradient S-band Backward Travelling Wave accelerating cavity for medical application (v = 0.38c) has been designed and constructed at CERN with a design gradient of 50 MV/m. In this paper, the high-power performance studies of this novel design carried out at the IFIC high-power laboratory are presented, as well as the analysis of the conditioning parameters in combination with numerical simulations.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"4 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-19DOI: 10.1016/j.net.2024.08.034
Xin Liu, Shengyuan Yan, Xiaodan Zhang
The standardized plant analysis risk human reliability analysis (SPAR-H) method is widely used for human reliability analysis to adjust the nominal human error probability (HEP) by assigning different multipliers to the performance shaping factors (PSFs). Nevertheless, SPAR-H suffers from assuming PSFs to be independent without considering any overlaps and dependencies. Therefore, this study introduces a new systematic method to analyze the relationships among the PSFs in SPAR-H qualitatively and quantitatively to obtain more reasonable HEP estimation results. The proposed method comprises three primary aspects: 1) a regularized autoencoder for the denoising and feature extraction of expert evaluation results, 2) the weighted influence non-linear gauge system-based adversarial interpretive structure modeling (WINGS-AISM) method to analyze the relationships among the PSFs and construct their causal hierarchy, and 3) a new relative weighting system to modify the PSF multipliers based on this hierarchy. The results of experiments comparing the proposed method with conventional methods highlight that our method effectively reduces the double counting of overlapping PSFs in SPAR-H, providing more reasonable and accurate HEP estimation results.
{"title":"Accounting for dependencies among performance shaping factors in SPAR-H using a regularized autoencoder and WINGS-AISM","authors":"Xin Liu, Shengyuan Yan, Xiaodan Zhang","doi":"10.1016/j.net.2024.08.034","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.034","url":null,"abstract":"The standardized plant analysis risk human reliability analysis (SPAR-H) method is widely used for human reliability analysis to adjust the nominal human error probability (HEP) by assigning different multipliers to the performance shaping factors (PSFs). Nevertheless, SPAR-H suffers from assuming PSFs to be independent without considering any overlaps and dependencies. Therefore, this study introduces a new systematic method to analyze the relationships among the PSFs in SPAR-H qualitatively and quantitatively to obtain more reasonable HEP estimation results. The proposed method comprises three primary aspects: 1) a regularized autoencoder for the denoising and feature extraction of expert evaluation results, 2) the weighted influence non-linear gauge system-based adversarial interpretive structure modeling (WINGS-AISM) method to analyze the relationships among the PSFs and construct their causal hierarchy, and 3) a new relative weighting system to modify the PSF multipliers based on this hierarchy. The results of experiments comparing the proposed method with conventional methods highlight that our method effectively reduces the double counting of overlapping PSFs in SPAR-H, providing more reasonable and accurate HEP estimation results.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"10 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-19DOI: 10.1016/j.net.2024.08.036
Xinbo Li, Jinxin Gong
This paper assesses the aging effects on the leak-tightness of containment under overpressure conditions. A global containment model and the detailed sub-models for the three main penetration regions in the containment are established. The main aging forms and mechanisms of containment are clarified, and corresponding simulation schemes are provided. Through numerical simulation, the impacts of different aging forms on the failure pressure of containment are discussed from a deterministic perspective. Finally, the fragility and functional failure probability of containment under different aging conditions are evaluated. When 60 years of concrete degradation and prestress loss are considered, the pressure capacities of equipment hatch, personnel airlock, and pipe penetration are reduced by approximately 5 %. Upon further considering steel liner corrosion, when the corrosion degree reaches 30 %, the pressure capacities of these regions are reduced by 24.37 %, 25.52 %, and 22.83 %, respectively. Within the scope of this study, the impact of steel liner corrosion on the risk of containment leakage is the most pronounced, whereas the impact of concrete degradation is minimal. If steel liner corrosion occurs simultaneously in three penetration regions, the whole containment will fail to meet the probabilistic performance goal when the corrosion degree reaches 30 %.
{"title":"Assessment of leak-tightness for nuclear reactor containment under overpressure conditions considering aging effects","authors":"Xinbo Li, Jinxin Gong","doi":"10.1016/j.net.2024.08.036","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.036","url":null,"abstract":"This paper assesses the aging effects on the leak-tightness of containment under overpressure conditions. A global containment model and the detailed sub-models for the three main penetration regions in the containment are established. The main aging forms and mechanisms of containment are clarified, and corresponding simulation schemes are provided. Through numerical simulation, the impacts of different aging forms on the failure pressure of containment are discussed from a deterministic perspective. Finally, the fragility and functional failure probability of containment under different aging conditions are evaluated. When 60 years of concrete degradation and prestress loss are considered, the pressure capacities of equipment hatch, personnel airlock, and pipe penetration are reduced by approximately 5 %. Upon further considering steel liner corrosion, when the corrosion degree reaches 30 %, the pressure capacities of these regions are reduced by 24.37 %, 25.52 %, and 22.83 %, respectively. Within the scope of this study, the impact of steel liner corrosion on the risk of containment leakage is the most pronounced, whereas the impact of concrete degradation is minimal. If steel liner corrosion occurs simultaneously in three penetration regions, the whole containment will fail to meet the probabilistic performance goal when the corrosion degree reaches 30 %.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"27 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-18DOI: 10.1016/j.net.2024.08.031
M.H.A. Mhareb, M.I. Sayyed, Rahman I. Mahdi, Kawa M. Kaky, M. Kh Hamad, Abed Jawad Kadhim
In this investigation, we reported three glass samples of Nd (III) ions doped boro-tellurite-germanite glasses. The chemical composition of (35-x) BO–20TeO-10GeO-35MgO-xNdO where x = 2.5, 5, and 7.5, all in mol%, was used to synthesize an optical glass. XRD, FTIR, and optical absorption were utilized to evaluate the structural and optical properties of Nd2.5, Nd5.0, and Nd7.5. X-ray diffraction was measured in the spectra range of 10–80°. Additionally, spectra of FT-IR in the wavenumber range of 400–4000 cm were reported to investigate all structural groups. Several absorption peaks related to the transitions from ground level I to the other excited state were investigated. Various mechanical, optical, and physical properties were calculated theoretically and analyzed to determine the role of the rare earth ions (Nd). The optical electronegativity (χ) and optical basicity (Λ) results showed a reduction in the strength of the bond and formed an ionic bond in the glass structure due to adding NdO. These results align with the reduction in the elastic modulus results by adding NdO instead of BO. Radiation shielding parameters like HVL, TVL, MFP, and Z were thoroughly reported for all Nd2.5, Nd5.0, and Nd7.5, which showed slight improvement when NdO was added instead of BO.
在这项研究中，我们报告了三种掺杂钕 (III) 离子的硼碲锗石玻璃样品。我们采用 (35-x) BO-20TeO-10GeO-35MgO-xNdO 的化学成分合成了一种光学玻璃，其中 x = 2.5、5 和 7.5，均为 mol%。利用 X 射线衍射、傅立叶变换红外光谱和光学吸收来评估 Nd2.5、Nd5.0 和 Nd7.5 的结构和光学特性。X 射线衍射的光谱范围为 10-80°。此外，还报告了波长范围为 400-4000 厘米的傅立叶变换红外光谱，以研究所有结构基团。研究了与从基态 I 到其他激发态跃迁有关的几个吸收峰。对各种机械、光学和物理特性进行了理论计算和分析，以确定稀土离子（钕）的作用。光学电负性（χ）和光学碱性（Λ）结果表明，加入氧化钕后，玻璃结构中的键强度降低，形成了离子键。这些结果与添加氧化钕而不是氧化银后弹性模量降低的结果一致。对所有 Nd2.5、Nd5.0 和 Nd7.5 的辐射屏蔽参数（如 HVL、TVL、MFP 和 Z）进行了详细报告，结果表明，添加 NdO 而不是 BO 后，辐射屏蔽参数略有改善。
{"title":"Role of Nd (III) ions on B2O3–TeO2-GeO2-MgO glass composition for optical and ionizing protection application","authors":"M.H.A. Mhareb, M.I. Sayyed, Rahman I. Mahdi, Kawa M. Kaky, M. Kh Hamad, Abed Jawad Kadhim","doi":"10.1016/j.net.2024.08.031","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.031","url":null,"abstract":"In this investigation, we reported three glass samples of Nd (III) ions doped boro-tellurite-germanite glasses. The chemical composition of (35-x) BO–20TeO-10GeO-35MgO-xNdO where x = 2.5, 5, and 7.5, all in mol%, was used to synthesize an optical glass. XRD, FTIR, and optical absorption were utilized to evaluate the structural and optical properties of Nd2.5, Nd5.0, and Nd7.5. X-ray diffraction was measured in the spectra range of 10–80°. Additionally, spectra of FT-IR in the wavenumber range of 400–4000 cm were reported to investigate all structural groups. Several absorption peaks related to the transitions from ground level I to the other excited state were investigated. Various mechanical, optical, and physical properties were calculated theoretically and analyzed to determine the role of the rare earth ions (Nd). The optical electronegativity (χ) and optical basicity (Λ) results showed a reduction in the strength of the bond and formed an ionic bond in the glass structure due to adding NdO. These results align with the reduction in the elastic modulus results by adding NdO instead of BO. Radiation shielding parameters like HVL, TVL, MFP, and Z were thoroughly reported for all Nd2.5, Nd5.0, and Nd7.5, which showed slight improvement when NdO was added instead of BO.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"57 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-18DOI: 10.1016/j.net.2024.08.035
Marwa A. Shewita , Ebrahiem Esmail Ebrahiem , C. Allison , Moustapha Salem Mansour , Ayah E. Elshahat , Mahmoud M. Taha
The current work investigates a computational model to study the thermal and hydraulic air behavior during the natural circulation at air ingression and accidents. This is done with the RHYS coupling ASYST VER 4 package. The test facility considered for the present study is a dual vertical channel facility comprised of two parallel channels connected to the upper and lower plenum. The flow fields in the heated and cooled channels were comprehensively characterized by analyzing axial temperature and velocity distributions using varied uniform iso-flux (100–1400 W/m2) and different outer surface temperatures (278, 288, 298, and 308 K). Temperature and velocity reversal recorded after maximal spots due to natural convection. The temperature rise from 278 to 308 K gave an average of 25.51 and 25.19° increase in air and inner wall temperatures, respectively, while air velocity increases at high cooling intensity (278 K) within the heated channel, in the cooled channel, low cooling intensity (308 K) resulted in higher velocity. The convective heat transfer is represented in terms of heat transfer coefficients, which are used to compute the Nusselt number. Additionally, the ASYST model was validated with data from literature sources, indicating strong agreement.
目前的工作研究了一个计算模型，以研究空气进入和事故发生时自然循环过程中的热和水力空气行为。该模型由 RHYS 耦合 ASYST VER 4 软件包完成。本研究考虑的试验设备是双垂直通道设备，由两个平行通道组成，分别连接到上下风箱。通过使用不同的均匀等流量（100-1400 W/m）和不同的外表面温度（278、288、298 和 308 K）分析轴向温度和速度分布，对加热和冷却通道中的流场进行了综合表征。由于自然对流，在最大光斑之后记录到温度和速度反转。温度从 278 K 升至 308 K 时，空气和内壁温度分别平均上升了 25.51 和 25.19°，而在加热通道中，冷却强度高（278 K）时空气流速增加，在冷却通道中，冷却强度低（308 K）时流速增加。对流传热用传热系数表示，用于计算努塞尔特数。此外，ASYST 模型还与文献来源的数据进行了验证，结果表明两者非常吻合。
{"title":"Investigation of computational model for the natural circulation at dual channel facility","authors":"Marwa A. Shewita , Ebrahiem Esmail Ebrahiem , C. Allison , Moustapha Salem Mansour , Ayah E. Elshahat , Mahmoud M. Taha","doi":"10.1016/j.net.2024.08.035","DOIUrl":"10.1016/j.net.2024.08.035","url":null,"abstract":"<div><div>The current work investigates a computational model to study the thermal and hydraulic air behavior during the natural circulation at air ingression and accidents. This is done with the RHYS coupling ASYST VER 4 package. The test facility considered for the present study is a dual vertical channel facility comprised of two parallel channels connected to the upper and lower plenum. The flow fields in the heated and cooled channels were comprehensively characterized by analyzing axial temperature and velocity distributions using varied uniform iso-flux (100–1400 W/m<sup>2</sup>) and different outer surface temperatures (278, 288, 298, and 308 K). Temperature and velocity reversal recorded after maximal spots due to natural convection. The temperature rise from 278 to 308 K gave an average of 25.51 and 25.19° increase in air and inner wall temperatures, respectively, while air velocity increases at high cooling intensity (278 K) within the heated channel, in the cooled channel, low cooling intensity (308 K) resulted in higher velocity. The convective heat transfer is represented in terms of heat transfer coefficients, which are used to compute the Nusselt number. Additionally, the ASYST model was validated with data from literature sources, indicating strong agreement.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"56 11","pages":"Pages 4929-4937"},"PeriodicalIF":2.6,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-17DOI: 10.1016/j.net.2024.08.032
Tao Wu, Jie Wang, Qiuyu Sun, Yifan Yang, Qingyu Si, Chenyu Liang, Guoming Liu, Aijun Mi, Sheng Wang
Tungsten has been widely used for gamma-ray and X-ray radiation shielding, which is one of the main elements of shielding materials. Compared with traditional lead-containing shielding materials, tungsten-containing shielding materials have several advantages, such as good chemical stability, a high melting point and relative environmental friendliness. Considering the recycling of resources, the optimization of pyrolysis temperature and pyrolysis duration of tungsten-filled Vinyl-Methyl-Silicone-based flexible shielding materials needs to be studied. In this paper, these tungsten-filled Vinyl-Methyl-Silicone-based flexible shielding materials were initially recycled using pyrolysis. Subsequently, the crystal structures, surface chemical states and the tungsten concentration after pyrolysis in an argon atmosphere were characterized. In order to increase the tungsten recycling rate, the pyrolyzed samples were further recycled using the ultrasonic cleaning method. Furthermore, the influence of ultrasonic cleaning on tungsten recycling rate and surface morphologies was characterized and analyzed. It is found that the tungsten recycling rate of tungsten-filled Vinyl-Methyl-Silicone based flexible gamma/X-ray shielding material was around 69.9 wt%-81.6 wt% by using the pyrolysis method, while the recycling rate of tungsten can exceed 90.0 wt% by ultrasonic cleaning after pyrolysis.
钨已被广泛用于伽马射线和 X 射线辐射屏蔽，是屏蔽材料的主要元素之一。与传统的含铅屏蔽材料相比，含钨屏蔽材料具有化学稳定性好、熔点高、相对环保等优点。考虑到资源的循环利用，需要对填充钨的乙烯基-甲基-硅基柔性屏蔽材料的热解温度和热解持续时间进行优化研究。本文利用热解法对这些钨填充乙烯基-甲基-硅基柔性屏蔽材料进行了初步回收。随后，在氩气环境中对热解后的晶体结构、表面化学状态和钨浓度进行了表征。为了提高钨的回收率，热解后的样品使用超声波清洗法进一步回收。此外，还表征和分析了超声波清洗对钨回收率和表面形貌的影响。研究发现，使用热解方法，钨填充的乙烯基-甲基-硅基柔性伽马/X 射线屏蔽材料的钨回收率约为 69.9%-81.6 wt%，而热解后通过超声波清洗，钨的回收率可超过 90.0 wt%。
{"title":"Recycling efficiency optimization of tungsten-filled Vinyl-Methyl-Silicone-based flexible gamma ray shielding materials","authors":"Tao Wu, Jie Wang, Qiuyu Sun, Yifan Yang, Qingyu Si, Chenyu Liang, Guoming Liu, Aijun Mi, Sheng Wang","doi":"10.1016/j.net.2024.08.032","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.032","url":null,"abstract":"Tungsten has been widely used for gamma-ray and X-ray radiation shielding, which is one of the main elements of shielding materials. Compared with traditional lead-containing shielding materials, tungsten-containing shielding materials have several advantages, such as good chemical stability, a high melting point and relative environmental friendliness. Considering the recycling of resources, the optimization of pyrolysis temperature and pyrolysis duration of tungsten-filled Vinyl-Methyl-Silicone-based flexible shielding materials needs to be studied. In this paper, these tungsten-filled Vinyl-Methyl-Silicone-based flexible shielding materials were initially recycled using pyrolysis. Subsequently, the crystal structures, surface chemical states and the tungsten concentration after pyrolysis in an argon atmosphere were characterized. In order to increase the tungsten recycling rate, the pyrolyzed samples were further recycled using the ultrasonic cleaning method. Furthermore, the influence of ultrasonic cleaning on tungsten recycling rate and surface morphologies was characterized and analyzed. It is found that the tungsten recycling rate of tungsten-filled Vinyl-Methyl-Silicone based flexible gamma/X-ray shielding material was around 69.9 wt%-81.6 wt% by using the pyrolysis method, while the recycling rate of tungsten can exceed 90.0 wt% by ultrasonic cleaning after pyrolysis.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"14 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The urgent requirement for sustainable and dependable energy sources has stimulated an increased fascination with precisely forecasting nuclear energy generation. This work utilizes sophisticated regression modeling approaches, namely XGBoost, to predict nuclear energy generation by leveraging economic indices such as Gross Domestic Product (GDP). Each model's prediction accuracy has been evaluated by examining historical data on nuclear energy output and GDP from various locations. Here, measures such as mean squared error (MSE) and coefficient of determination (R2) to analyze their effectiveness have been used. The results of this study demonstrate that the XGBoost model outperforms standard regression approaches, showing greater R2 values and lower MSE scores. Furthermore, the consequences of these discoveries for the development of energy policy offer possible directions for future study in energy forecasting. This study provides useful insights for energy planners and policymakers, enabling a more profound comprehension of the complex relationship between economic indicators and nuclear energy generation.
{"title":"Advancing nuclear energy forecasting: Exploring regression modeling techniques for improved accuracy","authors":"Anjali Nighoskar, Preeti Chaurasia, Nagendra Singh","doi":"10.1016/j.net.2024.08.013","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.013","url":null,"abstract":"The urgent requirement for sustainable and dependable energy sources has stimulated an increased fascination with precisely forecasting nuclear energy generation. This work utilizes sophisticated regression modeling approaches, namely XGBoost, to predict nuclear energy generation by leveraging economic indices such as Gross Domestic Product (GDP). Each model's prediction accuracy has been evaluated by examining historical data on nuclear energy output and GDP from various locations. Here, measures such as mean squared error (MSE) and coefficient of determination (R2) to analyze their effectiveness have been used. The results of this study demonstrate that the XGBoost model outperforms standard regression approaches, showing greater R2 values and lower MSE scores. Furthermore, the consequences of these discoveries for the development of energy policy offer possible directions for future study in energy forecasting. This study provides useful insights for energy planners and policymakers, enabling a more profound comprehension of the complex relationship between economic indicators and nuclear energy generation.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"77 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-16DOI: 10.1016/j.net.2024.08.030
Soohyeok Lee , Hyoungtaek Kim , Hwijoon Jung , Kyung Taek Lim
This paper explores the implementation of machine learning-based algorithms for TL dose assessment. It focuses on the radiation field classification, performance quotient evaluation, and shallow and deep dose equivalent assessment of ANN and LGBM, in comparison to the traditional method of DT. We evaluate these algorithms based on the element response data measured by TLD. A data set was built for training, and the base element responses of test categories were amplified, and normalized to 1 mSv Cs-137 within the range of ±3 %. Both algorithms consist of five subset models for classifying radiation fields and identifying ratios of mixed fields. The LGBM showed the best accuracy in classifying considered radiation fields and the lowest performance quotients. By comparing the tolerance levels of deep dose and shallow dose equivalents among the three algorithms, the LGBM yields the smallest difference between the predicted and true dose equivalents. This smaller difference implies the LGBM offers the least bias and standard deviation in the expected value, giving higher accuracy and precision in dose assessment over the traditional DT method. The findings from this study further contribute to the adoption of ML-based algorithms for TL dose assessment, underscoring its importance in the field.
{"title":"Comparative analysis of machine learning-based dose assessment algorithms for TL dosimetry","authors":"Soohyeok Lee , Hyoungtaek Kim , Hwijoon Jung , Kyung Taek Lim","doi":"10.1016/j.net.2024.08.030","DOIUrl":"10.1016/j.net.2024.08.030","url":null,"abstract":"<div><div>This paper explores the implementation of machine learning-based algorithms for TL dose assessment. It focuses on the radiation field classification, performance quotient evaluation, and shallow and deep dose equivalent assessment of ANN and LGBM, in comparison to the traditional method of DT. We evaluate these algorithms based on the element response data measured by TLD. A data set was built for training, and the base element responses of test categories were amplified, and normalized to 1 mSv Cs-137 within the range of ±3 %. Both algorithms consist of five subset models for classifying radiation fields and identifying ratios of mixed fields. The LGBM showed the best accuracy in classifying considered radiation fields and the lowest performance quotients. By comparing the tolerance levels of deep dose and shallow dose equivalents among the three algorithms, the LGBM yields the smallest difference between the predicted and true dose equivalents. This smaller difference implies the LGBM offers the least bias and standard deviation in the expected value, giving higher accuracy and precision in dose assessment over the traditional DT method. The findings from this study further contribute to the adoption of ML-based algorithms for TL dose assessment, underscoring its importance in the field.</div></div>","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"56 12","pages":"Pages 5414-5421"},"PeriodicalIF":2.6,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-16DOI: 10.1016/j.net.2024.08.029
Xin Wang, Ze Xu, Yulan Liu, Biao Wang
The elastoplastic mechanical behavior of Zircaloy-4 (Zr-4) cladding, coated with chromium (Cr) or FeCrAl on its surface, is explored under the coupled effects of multi-field coupling. Utilizing the Finite Element Software ABAQUS, simulations are conducted to calculate the evolution of stress and strain over two complete fuel cycles. Comparisons are drawn between the coated and uncoated Zircaloy-4 cladding materials. The results indicate that the application of surface coatings significantly mitigates stress levels in the cladding during the first fuel cycle. During the second fuel cycle, all three types of cladding exhibit relatively minor plastic strain, which is attributed to the unloading and reloading process between cycles. Notably, the plastic zone propagates from the interior to the exterior of the cladding. When compared to traditional Zircaloy-4 cladding, the coated cladding exhibits improved elastoplastic mechanical behavior. The operational mechanism of the coating for different stresses in cylindrical coordinates and its response to unloading and reloading cycles are also investigated. Specifically, the coated claddings exhibit an evident delay in reaching full plasticity compared to uncoated claddings. Furthermore, FeCrAl coating material initially shows good performance, and it needs to be verified in more aspects in the future. Results and Conclusions in this paper can provide reference and guidance for future experiments.
{"title":"Elastoplastic mechanical behavior analysis of surface-coated Zircaloy-4 cladding under multi-field coupling","authors":"Xin Wang, Ze Xu, Yulan Liu, Biao Wang","doi":"10.1016/j.net.2024.08.029","DOIUrl":"https://doi.org/10.1016/j.net.2024.08.029","url":null,"abstract":"The elastoplastic mechanical behavior of Zircaloy-4 (Zr-4) cladding, coated with chromium (Cr) or FeCrAl on its surface, is explored under the coupled effects of multi-field coupling. Utilizing the Finite Element Software ABAQUS, simulations are conducted to calculate the evolution of stress and strain over two complete fuel cycles. Comparisons are drawn between the coated and uncoated Zircaloy-4 cladding materials. The results indicate that the application of surface coatings significantly mitigates stress levels in the cladding during the first fuel cycle. During the second fuel cycle, all three types of cladding exhibit relatively minor plastic strain, which is attributed to the unloading and reloading process between cycles. Notably, the plastic zone propagates from the interior to the exterior of the cladding. When compared to traditional Zircaloy-4 cladding, the coated cladding exhibits improved elastoplastic mechanical behavior. The operational mechanism of the coating for different stresses in cylindrical coordinates and its response to unloading and reloading cycles are also investigated. Specifically, the coated claddings exhibit an evident delay in reaching full plasticity compared to uncoated claddings. Furthermore, FeCrAl coating material initially shows good performance, and it needs to be verified in more aspects in the future. Results and Conclusions in this paper can provide reference and guidance for future experiments.","PeriodicalId":19272,"journal":{"name":"Nuclear Engineering and Technology","volume":"3 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142207252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：