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面向企业信用风险评估的多视角异质图神经网络方法

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计算机研究与发展 2024年第8期61卷 1957-1967页

作者：魏少朋梁婷赵宇庄福振任福继西南财经大学工商管理学院成都611130 西南财经大学会计学院成都611130 金融智能与金融工程四川省重点实验室(西南财经大学) 成都611130 北京航空航天大学人工智能研究院北京100191 电子科技大学计算机科学与工程学院(网络空间安全学院) 成都611731

企业信用风险评估是一个重要且具有挑战的问题.由于金融市场中存在大量的异质关联关系,使得异质图神经网络天然适合建模企业信用风险.然而,现有大部分研究不能充分捕捉到复杂金融网络中企业的综合信用风险.针对此问题,提出了一个面向企... 详细信息

企业信用风险评估是一个重要且具有挑战的问题.由于金融市场中存在大量的异质关联关系,使得异质图神经网络天然适合建模企业信用风险.然而,现有大部分研究不能充分捕捉到复杂金融网络中企业的综合信用风险.针对此问题,提出了一个面向企业信用风险评估的多视角异质图神经网络方法——CRGNN.该方法包含自身风险编码器以及传染风险编码器,其中自身风险编码器建模基于企业特征信息的自身风险,传染风险编码器由新提出的分层异质图Transformer网络和分层异质图特征注意力网络2个子模块组成.这2个模块分别挖掘基于企业不同邻居视角的传染风险和基于不同特征维度视角的传染风险.为了充分利用异质关系信息,2个模块都采用了分层机制.在企业破产预测数据集SMEsD和企业信用评估数据集ECAD上进行了大量的实验,AUC指标相比最优基线模型分别提高了3.98个百分点和3.47个百分点.

关键词：图神经网络信用风险评估传染风险深度学习金融科技

Robust dual-channel correlation algorithm for complex weak target detection with wideband radar

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Journal of Systems Engineering and Electronics 2023年第5期34卷 1130-1146页

作者： DAI Yan LIU Dan LI Chuanming wei shaopeng HU Qingrong Beijing Institute of Radio Measurement Beijing 100854China College of Oceanography and Space Informatics China University of Petroleum(East China)Qingdao 257099China Defense Technology Academy of China Aerospace Science and Industry Corporation Limited Beijing 100070China

In the scene of wideband radar,due to the spread of target scattering points,the attitude and angle of view of the target constantly change in the process of *** is difficult to predict,and the actual echo of multiple scattered points is not fully matched with the transmitted ***,it is challenging for the traditional matching filter method to achieve a complete matching effect in wideband echo *** addition,the energy dispersion of complex target echoes is still a problem in radar target detection under broadband ***,this paper proposes a wideband target detection method based on dualchannel correlation processing of range-extended *** method fully uses the spatial distribution characteristics of target scattering points of echo signal and the matching characteristics of the dual-channel point extension function *** radial accumulation of wideband target echo signal in the complex domain is realized through the adaptive correlation processing of a dual-channel echo *** accu-mulation effect of high matching degree is achieved to improve the detection probability and the performance of wideband ***,electromagnetic simulation experiments and measured data verify that the proposed method has the advan-tages of high signal to noise ratio(SNR)gain and high detection probability under low SNR conditions.

关键词： wideband radar target detection dual-channel cor-relation

Hydrolysis mechanism of carbendazim hydrolase from the strain Microbacterium ***-6F

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Journal of Environmental Sciences 2017年第4期29卷 171-177页

作者： Ji Lei shaopeng wei Lijun Ren Shibin Hu Peng Chen Key Laboratory of Disaster Survey and Mechanism Simulation of Shaanxi Province College of Chemistry and Chemical EngineeringBaoji University of Arts and Sciences College of Resources and Environment College of Life Sciences and College of Plant ProtectionNorthwest A&F University

The carbendazim（MBC） hydrolyzing enzyme gene was cloned and heterologously expressed in Escherichia coli BL21（DE3） from a newly isolated MBC-degrading bacterium strain Microbacterium sp. strain djl-6F. High performance liquid chromatography-mass spectrometry（HPLC-MS）analysis revealed that purified MheI-6F protein catalyzes direct hydrolysis of MBC into2-aminobenzimidazole（2-AB） with a high turnover rate and moderate affinity（Kmof6.69 μmol/L and kcatof 160.88/min） without the need for any cofactors. The optimal catalytic condition of MheI-6F was identified as 45°C, pH 7.0. The enzymatic activity of MheI-6F was found to be diminished by metal ions, and strongly inhibited by sodium dodecyl sulfate（SDS）.Through generating amino acid mutations in MheI-6F, Cys16 and Cys222 were identified as the catalytic groups that are essential for the hydrolysis of MBC. This is the first report on the biodegradation of MBC at the enzymatice level.

关键词： Carbendazim Microbacterium sp.djl-6F Hydrolase MheI-6F

Process improvement in laser hot wire cladding for martensitic stainless steel based on the Taguchi method

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Frontiers of Mechanical Engineering 2016年第3期11卷 242-249页

作者： Zilin HUANG Gang WANG shaopeng wei Changhong LI Yiming RONG School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing 100044 China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University Beijing 100084 China Mechanical and Energy Engineering Department South University of Science and Technology of China Shenzhen 518055 China

Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved by using a quantitative method. In this work, volumetric defect ratio was proposed as the criterion to describe the integrity of forming quality for cladding layers. Laser deposition experiments with FV520B, one of martensitic stainless steels, were designed by using the Taguchi method. Four process variables, namely, laser power （P）, scanning speed （Vs）, wire feed rate （Vf）, and wire current （/）, were optimized based on the analysis of signal-to-noise （S/N） ratio. Metallurgic observation of cladding layer was conducted to compare the forming quality and to validate the analysis method. A stable and continuous process with the optimum parameter combination produced uniform microstructure with minimal defects and cracks, which resulted in a good metallurgical bonding interface.

关键词： process optimization Taguchi method signalto-noise (S/N) ratio volumetric defect ratio laser hot wire cladding

Cylindrocarpon olidum W1菌株代谢物中壳二孢氯素及其类似物的分离及抑菌活性

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农药学学报 2017年第4期19卷 457-464页

作者：魏少鹏姬志勤西北农林科技大学植物保护学院陕西杨凌712100 西北农林科技大学陕西省植物源农药研究与开发重点实验室陕西杨凌712100

采用硅胶柱层析及高效液相色谱等技术从冬青卫矛内生真菌Cylindrocarpon olidum W1次生代谢物中分离鉴定出8个抑菌活性化合物W1-1~W1-8。经核磁共振氢谱和碳谱、高分辨质谱等技术,并结合相关文献确认其为壳二孢氯素及其类似物,分别为Ili... 详细信息

采用硅胶柱层析及高效液相色谱等技术从冬青卫矛内生真菌Cylindrocarpon olidum W1次生代谢物中分离鉴定出8个抑菌活性化合物W1-1~W1-8。经核磁共振氢谱和碳谱、高分辨质谱等技术,并结合相关文献确认其为壳二孢氯素及其类似物,分别为Ilicicolin A(W1-1)、5-Chlorocolletorin B(W1-2)、Ilicicolin B(W1-3)、Deacetylchloronectrin(W1-4)、Ilicicolin C(W1-5)、壳二孢氯素(W1-6)、Cylindrol A_4(W1-7)和Cylindrol B(W1-8)。抑菌活性测定结果表明:壳二孢氯素及其类似物对烟草青枯病菌有较强的抑制作用,上述化合物的最小抑制浓度分别为6.2 5、3.1 3、>1 0 0、3.1 3、6.2 5、1 2.5、2 5和2 5μg/m L;化合物W 1-2、W1-4和W1-5对番茄灰霉病菌和油菜菌核病菌菌丝生长亦有较强的抑制作用,其中对番茄灰霉病菌的抑制中浓度(IC_(50))分别为36.45、21.60和26.69μg/m L,对油菜菌核病菌的抑制中浓度分别为20.21、16.79和12.11μg/m L。

关键词： Cylindrocarpon olidum W1 壳二孢氯素分离鉴定抑菌活性

Aspergillus flavus F52菌株鉴定及不同碳源对曲酸产量的影响

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微生物学报 2014年第10期54卷 1155-1160页

作者：魏少鹏徐楠姬志勤西北农林科技大学植物保护学院陕西杨凌712100

【目的】探明豇豆内生真菌F52的分类地位及不同碳源对曲酸产量的影响。【方法】采用形态观察及ITS序列分析对豇豆内生真菌F52进行分类鉴定;通过重结晶获得曲酸高纯度产物,采用核磁共振波谱、高分辨质谱及红外光谱对其进行结构鉴定;采用... 详细信息

【目的】探明豇豆内生真菌F52的分类地位及不同碳源对曲酸产量的影响。【方法】采用形态观察及ITS序列分析对豇豆内生真菌F52进行分类鉴定;通过重结晶获得曲酸高纯度产物,采用核磁共振波谱、高分辨质谱及红外光谱对其进行结构鉴定;采用高效液相色谱检测不同碳源对曲酸产量的影响。【结果】该曲酸产生菌为黄曲霉Aspergillus flavus F52;葡萄糖与蔗糖组成的复合碳源曲酸产量最高,乳糖的存在不利于曲酸的生成;该菌株发酵液中曲酸含量可达24.44 g/L。【结论】Aspergillus flavus F52是一株具有产业化开发价值的曲酸高产菌株。

关键词： Aspergillus flavus F52 曲酸碳源

基于ADMM的低仰角目标二维DOA估计算法

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电子与信息学报 2022年第8期44卷 2859-2866页

作者：马健钧魏少鹏马晖刘宏伟西安电子科技大学雷达信号处理国家重点实验室西安710071

针对面阵米波(VHF)雷达低仰角目标2维DOA估计问题,该文提出一种基于交替乘子法(ADMM)的快速2维DOA估计算法。该方法首先利用均匀面阵条件下方位、俯仰角无耦合的特性,将2维角度估计问题转化为两个1维角度估计问题,通过方位、俯仰维波束... 详细信息

针对面阵米波(VHF)雷达低仰角目标2维DOA估计问题,该文提出一种基于交替乘子法(ADMM)的快速2维DOA估计算法。该方法首先利用均匀面阵条件下方位、俯仰角无耦合的特性,将2维角度估计问题转化为两个1维角度估计问题,通过方位、俯仰维波束合成实现对目标信息提取;其次根据信号模型建立信号空域超完备表达式,利用ADMM方法完成对方位、俯仰角估计。该方法避免了2维联合估计复杂计算量,复杂度大大降低,且运算过程无需特征分解,进一步提高了运算效率。仿真结果表明了该算法的优越性。

关键词： 2维DOA估计低仰角目标米波面阵雷达 ADMM算法

冬青卫矛内生放线菌Streptomyces flavofuscus G1发酵液中抑菌活性成分研究

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农药学学报 2015年第5期17卷 616-621页

作者：曹艳魏少鹏姬志勤西北农林科技大学植物保护学院陕西杨凌712100

从冬青卫矛内生放线菌Streptomyces flavofuscus G1的发酵液中分离得到化合物G13和G19。经核磁共振波谱及质谱分析,并结合相关文献,两个化合物分别被鉴定为phencomycin(G13)和4'-deacetyl-(-)-griseusin A(G19)。抑菌活性测定结果表明:... 详细信息

从冬青卫矛内生放线菌Streptomyces flavofuscus G1的发酵液中分离得到化合物G13和G19。经核磁共振波谱及质谱分析,并结合相关文献,两个化合物分别被鉴定为phencomycin(G13)和4'-deacetyl-(-)-griseusin A(G19)。抑菌活性测定结果表明:G19对水稻白叶枯病菌Xanthomonas oryzae ***、铜绿假单孢菌Pseudomonas aeruginosa(1.203 1)、蜡状芽孢杆菌Bacillus cereus(1.184 6)及金黄色葡萄球菌Staphyloccocus aureus(1.008 9)等供试病原细菌具有强烈的抑制作用,其最低抑菌浓度(MIC)值均为1.56μg/m L;对苹果树腐烂病菌Valsa mali和小麦赤霉病菌Fusarium graminearum菌丝生长亦有明显的抑制作用,其IC50值分别为14.70和24.35μg/m L。而G13对植物病原真菌油菜菌核病菌Sclerotinia sclerotiorum和苹果树腐烂病菌***菌丝生长有强烈的抑制作用,其IC50值分别为5.21和4.82μg/m L。

关键词：冬青卫矛内生菌 Streptomyces flavofuscus G1 抑菌活性

An alfalfa MYB-like transcriptional factor MsMYBH positively regulates alfalfa seedling drought resistance and undergoes MsWAV3-mediated degradation

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Journal of Integrative Plant Biology 2024年第4期66卷 683-699页

作者： Kun Shi Jia Liu Huan Liang Hongbin Dong Jinli Zhang Yuanhong wei Le Zhou shaopeng Wang Jiahao Zhu Mingshu Cao Chris S.Jones Dongmei Ma Zan Wang College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Institute of Animal Sciences Chinese Academy of Agricultural SciencesBeijing 100193China AgResearch Grasslands Research Centre Palmerston North 4442New Zealand International Livestock Research Institute Nairobi 00100Kenya School of Ecology and Environment Ningxia UniversityYinchuan 750021China

Drought is a major threat to alfalfa(Medicago sativa L.)*** discovery of important alfalfa genes regulating drought response will facilitate breeding for drought-resistant alfalfa ***,we report a genome-wide association study of drought resistance in *** identified and functionally characterized an MYB-like transcription factor gene(MsMYBH),which increases the drought resistance in *** with the wild-types,the biomass and forage quality were enhanced in MsMYBH overexpressed *** RNA-seq,proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1,MsMCP2,MsPRX1A and MsCARCAB to improve their *** outcomes of such interactions include better water balance,high photosynthetic efficiency and scavenge excess H_(2)O_(2)in response to ***,an E3 ubiquitin ligase(MsWAV3)was found to induce MsMYBH degradation under long-term drought,via the 26S proteasome ***,variable-number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms,and the variation is associated with promoter ***,our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought-resistant *** discovery also offers new insights into the mechanisms of drought resistance in alfalfa.

关键词： alfalfa drought resistance E3 ubiquitin ligase MsMYBH MsWAV3 MYB-like transcriptional factor