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Cross sections for 14 MeV neutron interaction with lutetium isotopes and their theoretical excitation functions

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Chinese Physics C 2024年第5期48卷 244-256页

作者：宋月丽周丰群李勇张晓朋姬鹏飞孙小军 School of Electrical and Mechanical Engineering Pingdingshan UniversityPingdingshan 467000China School of Information Engineering Pingdingshan UniversityPingdingshan 467000China

The cross-sections for the 175Lu(n,p)175Yb,175Lu(n,α)172Tm,176Lu(n,α)173Tm,175Lu(n,2n)174mLu,and 175Lu(n,2n)174gLu reactions at 13.57,14.0314.62,and 14.86 MeV neutron energies were measured using an activation *** theoretical excitation functions of these reactions were calculated using the Talys-1.95 *** reaction cross-section data experimentally obtained were analyzed and compared with experimental data reported in the literature,data from five major evaluated nuclear data libraries of IAEA,and theoretical values based on *** data obtained at some neutron energies agree with some of the data reported in the literature and theoretical values based on *** consistency of the theoretical curves of excitation functions based on Talys-1.95 with the data obtained in this study and those reported in the literature is higher than that of the evaluation curves of excitation functions for the 175Lu(n,p)175Yb,175Lu(n,α)172 Tm,and 176Lu(n,α)173Tm *** study is helpful because it provides new evaluated reaction cross-section data on lutetium(which is a fusion reactor material),improves the quality of neutron-induced reaction cross section data libraries,and advances the research on related applications.

关键词： nuclear reaction cross sections of lutetium isotopes activation technique D-T neutron theoretical calculations Talys-1.95

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煤矿提升绞车主轴的设计及应用

自动化应用 2024年第16期65卷 179-181页

作者：冀鹏飞霍州煤电集团临汾宏大公司山西临汾031400

基于有限元仿真分析方法,介绍一种煤矿提升绞车主轴优化设计。在具体优化中,采用ANSYS软件对6种工况条件下煤矿提升绞车主轴的强度性能进行分析校核,然后根据分析结构确认应力集中区域,并根据安全系数法介绍主轴优化设计。通过有限元分... 详细信息

基于有限元仿真分析方法,介绍一种煤矿提升绞车主轴优化设计。在具体优化中,采用ANSYS软件对6种工况条件下煤矿提升绞车主轴的强度性能进行分析校核,然后根据分析结构确认应力集中区域,并根据安全系数法介绍主轴优化设计。通过有限元分析初步确认主轴优化设计可行性后,将优化设计应用于工程实践,进一步检验主轴优化设计的应用价值。

关键词：提升绞车主轴安全系数法有限元仿真

Clinical treatment procedure and experience of six gene-edited pigrhesus monkey heterotopic heart xenotransplantation

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Chinese Medical Journal 2024年第8期137卷 997-999页

作者： Bing Zhang pengfei ji Langang Peng Mengen Zhai jiayou Tang Lin Zhao Yan jin Baoling Xu Xiangni Lyu Linhe Lu Yenong Zhou Zhenxiao jin Weixun Duan Xiuling Yang Wei Yi jincheng Liu Department of Cardiovascular Surgery Xijing HospitalAir Force Medical UniversityXi’anShaanxi 710032China

Heart transplantation is an effective treatment for endstage heart failure;however,problems such as the severe shortage of donor hearts,rejection,the toxic effects of immunosuppressants,and serious postoperative complications remain.[1]Heart xenotransplantation is one of the most promising alternatives to address the shortage of allogeneic donor ***,the recipient survival rate and quality of life are affected by major obstacles,including immune rejection,complement and coagulation dysfunction,and infection.[2,3]Owing to the continuous improvement of gene editing strategies for donor pigs and anti-immune rejection strategies for non-human primate recipients.

关键词： donor treatment shortage

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面向煤矿机电设备的电磁干扰测试系统设计

能源与环保 2024年第6期46卷 202-205页

作者：冀鹏飞中国煤炭科工集团太原研究院有限公司山西太原030006 榆林天地煤机装备有限公司陕西榆林719000 煤矿采掘机械装备国家工程实验室山西太原030032

针对煤矿井下机电设备的电磁干扰问题,设计了一种电磁干扰测试系统,以评估井下机电设备的电磁兼容性和抗干扰能力。该系统的设计目标是提供一种可靠和高效的方法,用于检测和分析井下机电设备在复杂电磁环境中的工作性能。首先,介绍了煤... 详细信息

针对煤矿井下机电设备的电磁干扰问题,设计了一种电磁干扰测试系统,以评估井下机电设备的电磁兼容性和抗干扰能力。该系统的设计目标是提供一种可靠和高效的方法,用于检测和分析井下机电设备在复杂电磁环境中的工作性能。首先,介绍了煤矿井下机电设备面临的电磁干扰问题及其可能带来的危害。其次,详细描述了电磁干扰测试系统的组成和工作原理。该系统包括1个电磁辐射源和多个接收器,通过模拟真实的井下电磁环境,对机电设备进行干扰测试。接收器采集并分析井下设备的电磁辐射和敏感度,以评估其对外界电磁干扰的响应能力。最后,对该系统进行了实验验证,并与传统测试方法进行了比较。结果表明,该系统在测试效率和准确性方面均有显著改进。

关键词：井下机电设备电磁兼容性井下电磁环境电磁敏感度响应能力

A method of improving SFDRs of 1-bit signals for a monobit receiver

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Journal of Systems Engineering and Electronics 2022年第2期33卷 330-339页

作者： ji pengfei SHI Qingzhan LV Huan YUAN Naichang School of Electronic Sciences National University of Defense TechnologyChangsha 410073China

This paper proposes a method to improve the spu-rious-free dynamic ranges(SFDRs)of 1-bit sampled signals greatly,which is very beneficial to multi-tone signals ***,the relationship between the fundamental component and the third harmonic component of 1-bit sampled signals is analyzed for determining four contiguous special frequency bands,which do not contain any third harmonics inside and co-ver 77.8%of the whole Nyquist sampling frequency ***,we present a special 4-channel monobit receiver model,where appropriate filter banks are used to obtain four desired pass bands before 1-bit quantization and each channel can sample and process sampled data independently to achieve a good in-stantaneous dynamic range without sacrificing the real-time per-formance or computing *** simulation results show that the proposed method effectively eliminates the effect of the most harmonics on SFDRs and the mean SFDR is increased to to 20 ***,the multi-signals simulation results indicate that the maximum amplitude separation(dynamic range)of two signals in each channel is 12 dB while the proposed monobit re-ceiver can deal with up to eight simultaneous arrival *** general,the designing method proposed in this paper has a po-tential engineering value.

关键词： 1-bit signal monobit third harmonic component spurious-free dynamic range(SFDR)

Impacts of cone-structured interface and aperiodicity on nanoscalethermal transport in Si/Gesuperlattices

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Frontiers in Energy 2018年第1期12卷 137-142页

作者： pengfei ji Yiming RONG Yuwen ZHANG Yong TANG Department of Mechanical and Energy Engineering Southern Uni-versity of Science and Technology Shenzhen 518055 China Department of Mechanical and Aerospace Engineering University ofMissouri Columbia MO 65211 USA Key-Laboratory of Surface Functional Structure Manufacturing ofGuangdong Higher Education Institutes School of Mechanical andAutomotive Engineering South China University of TechnologyGuangzhou 510640 China

Si/Gesuperlattices are promising thermoelec- tric materials to convert thermal energy into electric power. The nanoscale thermal transport in Si/Gesuperlattices is investigated via molecular dynamics （MD） simulation in this short communication. The impact of Si and Ge interface on the cross-plane thermal conductivity reduction in the Si/Gesuperlattices is studied by designing cone- structured interface and aperiodicity between the Si and Ge layers. The temperature difference between the left and right sides of the Si/Gesuperlattices is set up for none- quilibrium MD simulation. The spatial distribution of temperature is recorded to examine whether the steady- state has been reached. As a crucial factor to quantify thermal transport, the temporal evolution of heat flux flowing through Si/Gesuperlattices is calculated. Com- pared with the even interface, the cone-structured interface contributes remarkable resistance to the thermal transport, whereas the aperiodic arrangement of Si and Ge layers with unequal thicknesses has a marginal influence on the reduction of effective thermal conductivity. The interface with divergent cone-structure shows the most excellent performance of all the simulated cases, which brings a 33% reduction of the average thermal conductivity to the other Si/Gesuperlattices with even, convergent cone-structured interfaces and aperiodic arrangements. The design of divergent cone-structured interface sheds promising lighton enhancing the thermoelectric efficiency of Si/Ge based materials.

关键词： thermoelectric material thermal transport Si/Gesuperlattics molecular dynamics (MD)

Fabrication of polymer/fluoride-containing salts blend composite membranes for CO_2 separation

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Journal of Natural Gas Chemistry 2010年第6期19卷 560-566页

作者： pengfei ji Yiming Cao Xingming jie Quan Yuan Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Poly （N,N-dimethylaminoethyl methacrylate）-poly （ethylene glycol methyl ether methacrylate）（PDMAEMA-PEGMEMA） and cesium fluoride （CsF） were blended and used as the separation material of composite *** fiber composite membranes were fabricated by coating the blend on polysulfone （PSf） hollow fiber *** of fluorine ion improved the separation performance of the *** concentration of coating solution was adjusted to obtain a membrane with high *** composite membrane showed good performance with the CO2 permeance of 30.4 GPU （1 GPU=10-6 cm3 （STP）/（cm 2 s cmHg））,and selectivities to CO2/N2,CO2/CH4,CO2/H2 and O2/N2 of 47.2,37.6,1.75 and 4.70,*** fluoride （KF）,due to its low cost,was also used as a substitute of CsF to prepare composite membrane and the permeation data showed that CsF can be replaced by *** effect of operating temperature on the permeation properties of the composite membrane was also investigated.

关键词： blend composite membrane coating CO2 separation hollow fiber

宽带跳频TDMA辐射源网群的定位及网群划分方法

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系统工程与电子技术 2024年第6期46卷 1838-1846页

作者：张曦蒙马育红胡卫东王青平季鹏飞袁乃昌国防科技大学电子科学学院湖南长沙410073 中国电子科技集团公司第十研究所四川成都610036

为了解决现有方法难以对宽带跳频时分多址(frequency hopping-time division multiple access,FH-TDMA)辐射源网群定位的问题,提出一种仅利用波达方向(direction of arrival,DOA)信息的多站定位及网群划分方法。首先通过模拟滤波对各站... 详细信息

为了解决现有方法难以对宽带跳频时分多址(frequency hopping-time division multiple access,FH-TDMA)辐射源网群定位的问题,提出一种仅利用波达方向(direction of arrival,DOA)信息的多站定位及网群划分方法。首先通过模拟滤波对各站接收到的信号进行频段划分,通过基于多相滤波的数字信道化方法把信号输出到多个信道中;然后通过直接定位(direct position determination,DPD)算法计算得出各时隙辐射源的位置;最后先通过不同参数的基于密度的噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)算法选择出最佳的辐射源定位结果,再根据提出的基于先验信息的改进K-means聚类算法进行网群划分。所提方法实现了采样率和信号处理速率的降低,且无需站间严格的时间同步。结果表明,所提方法有效估计出了辐射源的数量、位置,以及网群划分情况。

关键词：辐射源定位网群划分群目标跳频时分多址

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基于MAML-LSTM的服役涡轮叶片损伤状态评估方法

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航空学报 2024年第18期45卷 270-281页

作者：黄渭清李宁刘开霖付志忠纪鹏飞张生良董立伟孙燕涛北京理工大学机械与车辆学院北京100081 北京航空工程技术研究中心北京100076

准确评估涡轮叶片的损伤状态对于指导其大修/更换行为具有重要的意义,但由于涡轮叶片结构及服役环境的复杂性,现有技术手段难以模拟真实服役状态下的叶片损伤情况,而基于真实服役叶片的损伤数据进行损伤预测又存在数据采集成本高、样本... 详细信息

准确评估涡轮叶片的损伤状态对于指导其大修/更换行为具有重要的意义,但由于涡轮叶片结构及服役环境的复杂性,现有技术手段难以模拟真实服役状态下的叶片损伤情况,而基于真实服役叶片的损伤数据进行损伤预测又存在数据采集成本高、样本量小的客观限制。为此,针对小样本条件下服役涡轮叶片的损伤状态评估需求,提出一种基于元学习的损伤参数预测方法,在有限的服役数据基础上,实现对涡轮叶片损伤参数的有效预测。首先制备涡轮叶片不同叶身高度的切片试样,并通过场发射扫描电镜获取切片试样典型部位的微观图片,使用图像处理技术提取不同部位损伤数据,并根据图片所处部位的不同将损伤数据划分为不同训练任务数据;然后提出一种基于MAML-LSTM模型的涡轮叶片损伤参数预测方法,增强了服役条件与叶片损伤参数之间的相关性,建立了服役参数与损伤参数之间的有效映射。利用本文所提出的MAML-LSTM模型对测试集数据进行预测,预测结果的平均绝对百分比误差为7.55%,对比BP、RNN、LSTM、Bi-LSTM等神经网络的预测结果,所提出的模型在测试集上的平均绝对误差下降了至少52.37%,均方误差下降了至少76.98%。

关键词：元学习损伤预测涡轮叶片神经网络小样本微组织损伤