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Chinese Journal of Aeronautics 2021年第3期34卷 118-128页

作者： yubo he Qingzhen YANG Xiang GAO School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Comprehensive optimization design of serpentine nozzle with trapezoidal outlet was studied to improve its aerodynamic and electromagnetic scattering *** nozzles with different center offsets and different ratios of the bases of the trapezoidal outlet were generated based on curvature control *** Fluid Dynamics(CFD)simulations have been conducted to obtain the flow field in the nozzle,and Forward-Backward Iterative Physical Optics(FBIPO)method was applied to study the electromagnetic scattering characteristics of the *** Convergence Particle Swarm Optimization(GCPSO)algorithm based on Radial Basis Function(RBF)neural network was used to optimize the geometry of the nozzle in consideration of its aerodynamic and electromagnetic scattering *** results show that the GCPSO method based on RBF can be used to optimize the aerodynamic characteristics of the internal flow and the scattering characteristics of the cavity of the serpentine nozzle with irregular *** optimized model has a higher center offset and a lower ratio of the bases of the trapezoidal outlet after optimization compared to the original *** optimized model leads to a slight change in aerodynamic performance,with a total pressure recovery coefficient increase of 0.31%and a discharge coefficient increase of 0.41%.In addition,the Radar Cross Section(RCS)decreases also by around 83.33%and the overall performance is significantly improved,with a decrease of the optimized objective function by around 38.74%.

关键词： Forward-Backward Iterative Physical Optics(FBIPO) Guarantee Convergence Particle Swarm Optimization(GCPSO) Nozzle design Optimization design Radar Cross Section(RCS) Serpentine nozzle

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数学分析课堂教学创新与实践

大学（教学与教育） 2024年第7期 158-161页

作者：杨洁何郁波怀化学院数学与计算科学学院湖南怀化418000

数学分析是数学与应用数学专业核心基础课程,教学过程中存在学生学习兴趣不高、动手实践能力不强创新能力弱等痛点问题。针对教学过程中的痛点问题,课程团队通过构建翻转课堂,以数学建模竞赛、师范技能竞赛为抓手,融合线上线下、第一和... 详细信息

数学分析是数学与应用数学专业核心基础课程,教学过程中存在学生学习兴趣不高、动手实践能力不强创新能力弱等痛点问题。针对教学过程中的痛点问题,课程团队通过构建翻转课堂,以数学建模竞赛、师范技能竞赛为抓手,融合线上线下、第一和第二课堂、课程内容与思政案例,强化学生的数学理论基础,提升了学生的动手能力和创新能力。根据专业和课程的两个实际特点,坚持教学过程中以“小案例、大思政”的思政主线,强调和弘扬“学高为师,身正为范”的专业精神,培养教坛优秀传道者,以实现价值塑造、能力培养、知识探究“三位一体”的教学目标,落实立德树人的根本任务。

关键词：数学分析教学创新翻转课堂第二课堂数学建模

环印度洋地区被动陆缘盆地构造沉积演化及其对成藏要素的控制作用

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沉积与特提斯地质 2024年第1期44卷 71-85页

作者：李刚贺昱搏白国平邱海华王宁尹宇寒中国石油大学(北京)地球科学学院北京102249 北京大学能源研究院北京100871 油气资源与探测国家重点实验室北京102249 中国石油塔里木油田分公司新疆库尔勒841000

环印度洋周缘被动陆缘盆地油气资源潜力巨大,是当前世界油气勘探的热点地区之一。本文基于IHS商业数据库和前人研究成果等资料,厘定了环印度洋地区被动陆缘盆地构造演化史,分析了构造演化对盆地充填结构和成藏要素的影响,并利用蒙特卡... 详细信息

环印度洋周缘被动陆缘盆地油气资源潜力巨大,是当前世界油气勘探的热点地区之一。本文基于IHS商业数据库和前人研究成果等资料,厘定了环印度洋地区被动陆缘盆地构造演化史,分析了构造演化对盆地充填结构和成藏要素的影响,并利用蒙特卡洛模拟法评估了盆地油气资源潜力,优选了有利勘探区带。研究结果表明,环印度洋地区被动陆缘盆地经历了3期构造演化阶段,依次为裂前期、同裂谷期和被动陆缘期。根据盆地演化的主导阶段,研究区内被动陆缘盆地可分为拉张边缘裂前发育型、拉张边缘断坳叠置型、拉张边缘坳陷发育型和转换边缘断坳叠置型。盆地内烃源岩主要发育于裂前期—被动陆缘早期,不同地区的主力烃源岩层系不同;储集岩主要发育于裂前期—被动陆缘晚期;区域盖层则主要发育于被动陆缘期。资源评价结果显示,研究区内重点被动陆缘盆地待发现石油、天然气和凝析油可采资源量(均值)分别为4.49×10^(8) t,15.86×10^(12) m^(3)和5.23×10^(8) t,折合成油当量137.69×10^(8) t。澳大利亚西北陆架北卡那封盆地裂前中—上三叠统区带、东非地区鲁伍马盆地北部和坦桑尼亚盆地南部中白垩统—新近系三角洲-深水扇区带是最有潜力的勘探区带。

关键词：环印度洋被动陆缘盆地构造演化成藏要素资源评价

Detection of Malicious PDF Files Using a Two-Stage Machine Learning Algorithm

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Chinese Journal of Electronics 2020年第6期29卷 1165-1177页

作者： he Kang ZHU Yuefei he yubo LIU Long LU Bin LIN Wei State Key Laboratory of Mathematical Engineering and Advanced Computing

Portable document format(PDF) files are increasingly used to launch cyberattacks due to their popularity and increasing number of *** solutions have been developed to detect malicious files,but their accuracy decreases rapidly in face of new evasion *** explore how to improve the robustness of classifiers for detecting adversarial attacks in PDF *** replacement and the n-gram are implemented to extract robust features using proposed guiding *** the two-stage machine learning model,the objects are divided based on their types,and the anomaly detection model is first trained for each type *** former detection results are organized into tree-like information structure and treated as inputs to convolutional neural *** results show that the accuracy of our classifier is nearly 100% and the robustness against evasive samples is *** object features also enable the identification of different vulnerabilities exploited in malicious PDF files.

关键词： convolutional neural nets document handling feature extraction learning (artificial intelligence) pattern classification security of data trees (mathematics) robust feature extraction convolutional neural network tree-like information structure adversarial attack detection two-stage machine learning algorithm evasion techniques malicious files portable document format malicious PDF files classifier robustness anomaly detection model two-stage machine learning model Malicious PDF classification Robustness Guiding principles Two-stage classifier Convolutional neural network

Cr_(3)C_(2)质量浓度对Co-Cr_(3)C_(2)复合镀层微观结构及耐磨性的影响

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电镀与涂饰 2024年第8期43卷 18-26页

作者：陈翀宇卓健飞谢新汪镇涛何雨波王帅星杜楠南昌航空大学材料科学与工程学院江西南昌330063 中国航发长江动力有限公司湖南岳阳414001

[目的]研究Cr_(3)C_(2)颗粒质量浓度对Co-Cr_(3)C_(2)复合镀层结构及耐磨性的影响,以确定其最佳用量,提升Co-Cr_(3)C_(2)复合镀层的耐磨性。[方法]在镀钴溶液中加入不同质量分数的Cr_(3)C_(2)颗粒,采用电沉积法在GH4169合金表面制备Co-C... 详细信息

[目的]研究Cr_(3)C_(2)颗粒质量浓度对Co-Cr_(3)C_(2)复合镀层结构及耐磨性的影响,以确定其最佳用量,提升Co-Cr_(3)C_(2)复合镀层的耐磨性。[方法]在镀钴溶液中加入不同质量分数的Cr_(3)C_(2)颗粒,采用电沉积法在GH4169合金表面制备Co-Cr_(3)C_(2)复合镀层,通过扫描电子显微镜、能谱仪、显微硬度计及材料表面性能综合测试仪分析了不同颗粒添加量时所得Co-Cr_(3)C_(2)复合镀层的微观形貌、颗粒复合量、显微硬度及摩擦学性能。[结果]随着镀液中Cr_(3)C_(2)质量浓度的增大,Co-Cr_(3)C_(2)复合镀层的颗粒分布均匀性得到改善,颗粒复合量和显微硬度增大,但Cr_(3)C_(2)颗粒过量时会给复合镀层带来负面影响。Cr_(3)C_(2)质量浓度为70 g/L时,镀层中Cr_(3)C_(2)颗粒复合量达到最高的33.49%,截面显微硬度为626 HV.01,耐磨性最佳。Co-Cr_(3)C_(2)复合镀层主要发生磨粒磨损及轻微的粘着磨损。[结论]镀液中Cr_(3)C_(2)颗粒浓度显著影响着Co-Cr_(3)C_(2)复合镀层的结构和耐磨性,较佳的Cr_(3)C_(2)颗粒添加量为70 g/L。

关键词：钴碳化铬复合电沉积组织结构耐磨性成分

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基于双元变换的一类反常积分问题的计算

高师理科学刊 2024年第1期44卷 18-21,35页

作者：朱锦涵彭丽周珏良何郁波怀化学院数学与计算科学学院湖南怀化418000 岳阳县第一中学集英学校湖南岳阳414199

针对一类被积函数分母含ax^(4)+bx^(2)+c的有理分式的反常积分问题,利用引入双元变换的方法,结合组合计算方法和高次有理分式化成部分有理真分式的理论,给出了积分问题的计算方法.利用所给结论,计算并证明了二类积分问题.

关键词：高次有理分式双元变换组合计算法

搅拌对Co–Cr3C2复合电沉积过程及镀层耐磨性的影响

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电镀与涂饰 2024年第9期43卷 26-33页

作者：刘树静汪镇涛陈翀宇卓健飞何雨波王帅星杜楠南昌航空大学科技学院南昌航空大学材料科学与工程学院中国航发长江动力有限公司

[目的]搅拌是影响复合电沉积过程的关键因素，搅拌速率的控制对于调节复合镀层的结构和提高其耐磨性具有重要意义。[方法]通过阴极极化曲线和电化学阻抗谱测试，分析了搅拌速率对Co–Cr3C2复合电沉积过程的影响，考察了不同搅拌速率下所... 详细信息

[目的]搅拌是影响复合电沉积过程的关键因素，搅拌速率的控制对于调节复合镀层的结构和提高其耐磨性具有重要意义。[方法]通过阴极极化曲线和电化学阻抗谱测试，分析了搅拌速率对Co–Cr3C2复合电沉积过程的影响，考察了不同搅拌速率下所得Co–Cr3C2复合镀层的微观结构、Cr3C2颗粒复合量及耐磨性。[结果]搅拌速率较低（如270 r/min）时，镀液中Cr3C2颗粒传输效率不高，导致阴极表面Cr3C2颗粒较少，阴极极化作用较弱。搅拌速率为320～380 r/min时，Co–Cr3C2复合电沉积过程表现出较强的阴极极化作用和较低的双电层电容，有利于Cr3C2颗粒在阴极表面的吸附及其在镀层中复合量的增加。然而搅拌速率过高会导致镀层中颗粒复合量减少。搅拌速率为320 r/min时，Co–Cr3C2镀层的颗粒复合量最高，耐磨性最佳。[结论]搅拌主要通过促进颗粒输送和对电极表面颗粒的冲刷作用来影响电化学极化和镀层的颗粒复合量，进而改变镀层的耐磨性。

关键词：复合电沉积钴碳化铬搅拌速率微观结构耐磨性复合量

促甲状腺激素及甲状腺自身抗体与分化型甲状腺癌的关系研究

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中国医学文摘（耳鼻咽喉科学） 2024年第3期39卷 28-30页

作者：何聿波史松槟李奇功张国祥泗阳医院江苏宿迁223700

目的研究促甲状腺激素(TSH)及甲状腺自身抗体与分化型甲状腺癌(DTC)的关系。方法选择本院2022年1月-2022年12月收治100例甲状腺结节患者,根据“术后病理学结果”分良性组(良性甲状腺结节),恶性组(DTC患者)各50例,均行TSH、甲状腺自身抗... 详细信息

目的研究促甲状腺激素(TSH)及甲状腺自身抗体与分化型甲状腺癌(DTC)的关系。方法选择本院2022年1月-2022年12月收治100例甲状腺结节患者,根据“术后病理学结果”分良性组(良性甲状腺结节),恶性组(DTC患者)各50例,均行TSH、甲状腺自身抗体检测,检测结果分析。结果两组比较TPOAb指标无差异,P>0.05;较良性组,恶性组TSH、TgAb指标更高;恶性组TSH增高异常率(20.00%)高于良性组(8.00%);恶性组TgAb阳性率(16.00%)高于良性组(4.00%),χ^(2)=11.259,6.327;导致DTC疾病独立危险因素是TSH增高、TgAb阳性,P<0.05(具有统计学意义)。结论TSH增高、TgAb阳性是造成DTC疾病的独立危险因素,对疾病鉴别诊断有一定价值,为后期诊疗提供数据支持、改善预后,值得推崇。

关键词：促甲状腺激素甲状腺自身抗体分化型甲状腺癌检测结果

Dietary supplementation of laminarin improves the reproductive performance of sows and the growth of suckling piglets

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Journal of Animal Science and Biotechnology 2024年第1期15卷 329-343页

作者： Pengguang Zhang Guoyuan Jiang Chenghong Ma yubo Wang Enfa Yan Linjuan he Jianxin Guo Xin Zhang Jingdong Yin State Key Laboratory of Animal Nutrition and Feeding College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Maternal nutrition is essential in keeping a highly efficient production system in the pig *** has been shown to improve antioxidant capacity,reduce the inflammatory response,and favor the homeostasis of intestinal ***,the effect of dietary supplementation of laminarin on the reproductive performance of sows and the growth of suckling offspring remains *** A total of 40 Landrace×Yorkshire multiparous sows on d 85 of gestation,similar in age,body weight(BW),parity and reproductive performance,were randomly divided into four dietary treatments with 10 sows per treatment,receiving a control diet(basal pregnancy or lactating diets)and a basal diet supplemented with 0.025%,0.05%and 0.10%laminarin,*** experiment lasted from d 85 of gestation to d 21 of *** Laminarin supplementation linearly increased number born alive per litter(P=0.03),average daily feed intake(ADFI,Phe lactation of 1–21 d(P=0.02).Furthermore,maternal laminarin supplementation increased the average daily gain(ADG)of piglets while tending to reduce the culling and death rate before *** addition,alterations to the composition of colostrum and milk,as well as to serum inflammatory cytokines and immunoglobulins of sows were *** fecal microbiota profile of sows supported the improvement of reproductive performance in sows and the growth performance in suckling *** Dietary supplementation of laminarin during late pregnancy and lactation could significantly improve reproductive performance of sows and growth performance of piglets.

关键词： Fecal microbiota Laminarin Milk Piglets Reproductive performance Sows

Exploring differentiated improvement strategies of cultivated land quality in China

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 282-291页

作者： Wenguang CheN Xiangbin KONG yubo LIAO College of Land Science and Technology China Agricultural UniversityBeijing 100193China

Quality is the core feature of cultivated land. In the face of deteriorating cultivated land quality and growing food demand, improving cultivated land quality is a top priority for guaranteeing the sustainable use of resources and national food security. Cultivated land quality in the new era can be considered in four dimensions: suitability, contiguity, resistance and ecological stress. Cultivated land suitability in China shows a decreasing trend from east to west, cultivated land contiguity is high in the north-east and low in the south-west. In terms of cultivated land resistance, the number of strongly and weakly resistant cropping fields is small and spatially clustered. Cultivated land with ecological stress is mainly located in the northern region. Based on the current situation of cultivated land quality and the strategic needs of national high-quality development, China's future goals for improving cultivated land quality include four aspects: promoting the sustainable use of resources,improving the economic benefits of farming, coping with extreme meteorological disasters and meeting the transition of the food *** the backdrop of a volatile international environment and high domestic demand for food, China should guarantee a safe supply of staples, a stable supply of animal feed and a moderate supply of high-nutrient food. In the future, China should create three major food production spaces: highstandard, low-to medium-yield, and marginal cultivated land. China urgently needs to construct three paths to implement the goal of improving cultivated land quality, namely the development of high-standard cultivated land with the core of spatial optimization, resilience enhancement and scale coupling,the transformation of low-to medium-yield cultivated land with the core of obstacle elimination, tenure adjustment, ecological sustainable, and the conservation development of marginal cultivated land with a focus on sustainable use.

关键词： China cultivated land quality differentiated improvement food security