Plutonium management and Generation IV systems

This paper discusses the potential role of Generation IV nuclear energy systems in managing plutonium. It briefly reviews the Generation IV goals and their relevance to plutonium management. Each of the six selected Generation IV systems [very high temperature reactor (VHTR), gas-cooled fast reactor (GFR), sodium-cooled fast reactor (SFR), super-critical-water-cooled reactor (SCWR), lead-cooled fast reactor (LFR), molten salt reactor (MSR)] is briefly discussed. The main characteristics of each system are summarised and the capability for plutonium management indicated. The potential for the management of plutonium using Generation IV systems is briefly reviewed from a complete fuel cycle perspective to illustrate the issues in the context of a fleet of reactor and fuel cycle facilities.     

Construction management through bot: Taiwan high speed rall case

Build Operate Transfer (BOT)isanewprojectde liveringmethodtoimplementpublicinfrastructurepro jects .BOTincorporatesaprivatizedeffortintopublicin frastructuredevelopment.Theconcessionrightisgrantedtoaconsortiumwhoundertakesfinance ,design ,construc tion ,operation ,andmaintenanceofthedesiredfacilitiesandservices .Aftertheconcessionrightisexpired ,theownershipofthefacilityistransferredtothepublicowner.TheeconomicprosperityofTaiwaninthe 1 980’sandearly 1 990’sbroughtseveretrafficcongestioni…     

Using a modified CINDER90 routine in MCNPX 2.6.0 for the prediction of helium production in minor actinide targets

Fast reactors containing heterogeneous minor actinide (MA) target rods are now being modeled. When studying transmutation in these rods, helium production from α-decay must be considered since it is produced in substantial quantities. This research utilized an innovative method to calculate gas production by modifying the CINDER90 depletion code used by MCNPX 2.6.0 to include helium production from α-decay. The modified CINDER90 code was verified using the ORIGEN-ARP module of SCALE6. It was tested using the Sodium-Cooled Heterogeneous Innovative Burner Reactor model created at the University of South Carolina. It is recommended that the modified version of the cinder.dat file be distributed in subsequent MCNPX 2.6.0 releases for use in fast reactor calculations using heterogeneous MA target rods since it includes helium production otherwise not available from the current version.     

混合信号单片机C8051F060的DMA接口及编程

C8051F060是Cygnal公司新推出的一款高集成度混合信号单片机,该单片机具有16位1Msps的高性能模数转换器接口和专用于快速传送ADC结果数据的直接存储器存取接口DMA,本文介绍了DMA的原理及使用方法.     

有效特征参数分类正常与病理语音

采用残差信号的特征参数——基音幅值（Pitch Amplitude,PA）和频谱平坦度（Spectral Flatness of the Residue Signal,SFR）与语音信号倒谱域特征参数——倒谱峰值突出（Cepstral Peak Prominence,CPP）来区分正常与病理语音,在萨尔布吕肯语音数据库中选择自然音调的正常与病理语音/a/进行仿真实验。统计结果表明,与正常语音相比,病理语音的PA较小,SFR更接近零,CPP也较小。结合其他传统特征参数分析对比,证明SFR、PA和CPP更能有效分类正常与病理语音。通过不同分类算法比较,得出支持向量机的分类准确率相对更高。     

Formation of intermetallic compound at interface between rare earth elements and ferritic-martensitic steel by fuel cladding chemical interaction

The intermetallic compounds formation at interface between rare earth elements and clad material were investigated to demonstrate the effects of rare earth elements on fuel-cladding chemical interaction(FCCI)behavior.Mischmetal(70Ce-30La)and Nd were prepared as rare earth elements.Diffusion couple testing was performed on the rare earth elements and cladding(9Cr2W steel)near the operation temperature of(sodium-cooled fast reactor)SFR fuel.The performance of a diffusion barrier consisting of Zr and V metallic foil against the rare earth elements was also evaluated.Our results showed that Ce and Nd in the rare earth elements and Fe in the clad material interdiffused and reacted to form intermetallic species according to the parabolic rate law,describing the migration of the rare earth element.The diffusion of Fe limited the reaction progress such that the entire process was governed by the cubic rate law.Rare earth materials could be used as a surrogate for high burnup metallic fuels,and the performance of the barrier material was demonstrated to be effective.     

NBCM with Flat Roll in the Finish Stand

With the development of the market, it becomes a demanding task for producers to make flexible production schedules to shorten production cycle. Schedule-free rolling is needed. If the CVC work roll of the F6 and F7 stands in certain 2050 mm hot rolled strip mill are substituted by flat roll (aim to SFR) and the strip profile is controlled by the existing bending force, the control ability is not adequate. This fact has been tested through on-line experiment and has been given in this article. The NBCM (new backup roll crowning method) is recommended to improve the profile control ability. Finally the plastic deformation of the strip and the elastic deformation of the roll are analyzed by employing coupled calculation of rigid-plastic finite element method and G-function method, and the optimal range of the crown of backup roll is given theoretically.     

Enhancing TRU burning and Am transmutation in Advanced Recycling Reactor

This paper presents about conceptual designs of Advanced Recycling Reactor (ARR) focusing on enhancement in transuranics (TRU) burning and americium (Am) transmutation. The design has been conducted in the context of the Global Nuclear Energy Partnership (GNEP) seeking to close nuclear fuel cycle in ways that reduce proliferation risks, reduce the nuclear waste in the US and further improve global energy security. This study strives to enhance the TRU burning and the Am transmutation, assuming the development of related technologies in this study, while the ARR based on mature technologies was designed in the previous study. It has followed that the provided TRU burning core is designed to burn TRU at 28 kg/TW_thh, by adding moderator pins of B₄C (Enriched B-11) and the Am transmutation core will be able to transmute Am at 34 kg/TW_thh, by locating Am blanket of AmN around the TRU burning core. It indicates that these concepts improve TRU burning by 40-50% than the previous core and can transmute Am effectively, keeping the void reactivity acceptable.     

基于认知的LTE系统动态频谱分配

传统的软频率复用(SFR)无法适应长期演进(LTE)系统中业务的动态分布,可能导致小区中心和边缘区域频谱利用率不均。针对此问题,该文提出一种基于认知的LTE系统动态频谱分配方法(Cog-DSA)。该方法利用基站间的相互协作获得频谱使用状态信息,从而确定可用频谱集合,并评估来自邻小区的同频干扰,最终根据可用资源块的通信质量,对重负荷小区边缘进行频谱的动态借用和服务基站的灵活选择。仿真结果表明,所提方法能够有效改善频谱利用率,减少小区间干扰,显著提升边缘用户的传输速率。     

Improvement of a physical model for blockage formation of solid–liquid mixture flow with freezing for core safety evaluation of SFRs

The SIMMER code has been developed to analyze event progression during core disruptive accidents (CDAs) in sodium-cooled fast reactors. One of the key phenomena during CDAs is the discharge of molten fuel from the core region which reduces the reactivity effectively. The discharge flow is inhibited by blockage formation due to freezing of the molten fuel. Then, the blockage formation is enhanced by unmolten fuel which forms solid–liquid mixture flow with the molten fuel. A physical model for blockage formation of solid–liquid mixture flow with freezing in the SIMMER code is improved in this study to dissolve some inconsistencies between the modeling and the physical phenomena involved in the solid–liquid mixture flow with freezing for more precise evaluation of CDA. The improved model is validated with a systematical procedure through a benchmark analysis of an experiment. Consequently, experimental penetration behaviors are simulated reasonably by the SIMMER code analysis with the improved model while excessive blockage formation occurred in the analysis with the original model.