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Improving flight performance of UAVs by ice shape modulation

Chinese Journal of Aeronautics 2024年第8期37卷 49-62页

作者： Jiajun ZHANG Xuecheng liU Hua liANG like XIE Biao WEI Haohua ZONG Yun WU yinghong li National Key Lab of Aerospace Power System and Plasma Technology Air Force Engineering UniversityXi’an 710038China Institute of Aero-Engine School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China

Aircraft icing poses a great threat to flight *** response to the characteristics of high-power consumption,large volume,and heavy weight of traditional anti-/de-icing technologies,the concept of ice shape modulation is proposed,which is called ice tolerant ***,the flight performance of Unmanned Aerial Vehicle(UAV)was compared in three states:no ice,full ice,and modulated ice through flight *** was found that ice shape modulation has a significant improvement effect on the aerodynamic performance of aircraft under icing *** the three modulated ice shape conditions in this experiment,the lift coefficient of the UAV under different ice shape modulation conditions increased by 18%–33%,and the stalling angle was delayed by 3°-5°.Subsequently,the pressure distribution,streamlines in the flow field,and detached vortex distribution of the UAV model in these three states were obtained through numerical simulation,to study the mechanism of ice shape modulation on the aerodynamic performance of *** simulation found that the reason for the improvement of the wings effect after ice shape modulation is that the modulated area forms a leading-edge protrusion structure similar to a vortex *** structure prolongs the mixed flow region on the wings surface and reduces the trend of flow separation,which plays a role in increasing lift and reducing drag for UAVs under icing ***,a reverse reachable set that can be used for unexpected state recovery is used as the definition of flight safety boundaries,and an aircraft dynamics model is established to obtain flight safety boundaries for different *** has found that the flight safety boundary of the UAV in a no ice state is greater than that in a modulated ice state,and the safety boundary in a modulated ice state is greater than that in a full ice *** with the full ice state,the flight safety boundary after modulation has expanded by 27.0%.The sch

关键词： Ice shape modulation Aerodynamic performance Reachable set Flight safety UAV

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Machine learning for predicting fatigue properties of additively manufactured materials

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Chinese Journal of Aeronautics 2024年第4期37卷 1-22页

作者： Min YI Ming XUE Peihong CONG Yang SONG Haiyang ZHANG lingfeng WANG liucheng ZHOU yinghong li Wanlin GUO State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Institute for Frontier Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shenyang Engine Research Institute Shenyang 110015China liaoning Key Laboratory of Impact Dynamics on Aero Engine Shenyang 110015China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China

Fatigue properties of materials by Additive Manufacturing(AM) depend on many factors such as AM processing parameter, microstructure, residual stress, surface roughness, porosities, post-treatments, etc. Their evaluation inevitably requires these factors combined as many as possible, thus resulting in low efficiency and high cost. In recent years, their assessment by leveraging the power of Machine Learning(ML) has gained increasing attentions. A comprehensive overview on the state-of-the-art progress of applying ML strategies to predict fatigue properties of AM materials, as well as their dependence on AM processing and post-processing parameters such as laser power, scanning speed, layer height, hatch distance, built direction, post-heat temperature,etc., were presented. A few attempts in employing Feedforward Neural Network(FNN), Convolutional Neural Network(CNN), Adaptive Network-Based Fuzzy Inference System(ANFIS), Support Vector Machine(SVM) and Random Forest(RF) to predict fatigue life and RF to predict fatigue crack growth rate are summarized. The ML models for predicting AM materials' fatigue properties are found intrinsically similar to the commonly used ones, but are modified to involve AM features. Finally, an outlook for challenges(i.e., small dataset, multifarious features,overfitting, low interpretability, and unable extension from AM material data to structure life) and potential solutions for the ML prediction of AM materials' fatigue properties is provided.

关键词： Additive manufacturing Machine learning Fatigue life Fatigue crack growth rate Prediction

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Carrimycin inhibits coronavirus replication by decreasing the efficiency of programmed–1 ribosomal frameshifting through directly binding to the RNA pseudoknot of viral frameshift-stimulatory element

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2567-2580页

作者： Hongying li Jianrui li Jiayu li Hu li Xuekai Wang Jing Jiang Lei Lei Han Sun Mei Tang Biao Dong Weiqing He Shuyi Si Bin Hong yinghong li Danqing Song Zonggen Peng Yongsheng Che Jian-Dong Jiang CAMS Key Laboratory of Antiviral Drug Research Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Beijing Key Laboratory of Antimicrobial Agents Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Key Laboratory of Biotechnology of Antibiotics the National Health and Family Planning Commission(NHFPC)Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

The pandemic of SARS-CoV-2 worldwide with successive emerging variants urgently calls for small-molecule oral drugs with broad-spectrum antiviral ***,we show that carrimycin,a new macrolide antibiotic in the clinic and an antiviral candidate for SARS-CoV-2 in phase III trials,decreases the efficiency of programmed–1 ribosomal frameshifting of coronaviruses and thus impedes viral replication in a broad-spectrum *** binds directly to the coronaviral frameshift-stimulatory element(FSE)RNA pseudoknot,interrupting the viral protein translation switch from ORF1a to ORF1b and thereby reducing the level of the core components of the viral replication and transcription *** carrimycin with known viral replicase inhibitors yielded a synergistic inhibitory effect on *** the FSE mechanism is essential in all coronaviruses,carrimycin could be a new broad-spectrum antiviral drug for human coronaviruses by directly targeting the conserved coronaviral FSE *** finding may open a new direction in antiviral drug discovery for coronavirus variants.

关键词： Carrimycin Coronavirus Broad-spectrum antiviral activity Programmed-1 ribosomal frameshifting RNA pseudoknot Antiviral agent RNA target Synergistic inhibitory effect

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Chemical construction and anti-HCoV-OC43 evaluation of novel 10,12-disubstituted aloperine derivatives as dual cofactor inhibitors of TMPRSS2 and SR-B1

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Chinese Chemical Letters 2024年第5期35卷 201-206页

作者： Yulong Shi Fenbei Chen Mengyuan Wu Xin Zhang Runze Meng Kun Wang Yan Wang Yuheng Mei Qionglu Duan yinghong li Rongmei Gao Yuhuan li Hongbin Deng Jiandong Jiang Yanxiang Wang Danqing Song Beijing Key Laboratory of Antimicrobial Agents Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Department of Pharmacy Affiliated Hospital of Jining Medical UniversityJining Medical UniversityJining 272000China

Thirty-one new 10,12-disubstituted aloperine derivatives were subtly constructed through a selective oxidation on the 10-α-C-H induced by sulfonyl and a nucleophilic substitution with the stereoselectivity and *** them,compound 6b displayed a moderate anti-human coronavirus OC43(HCoV-OC43)potency and blocked the viral entry stage through a host mechanism of *** chemoproteomic techniques,both transmembrane serine protease 2(TMPRSS2)and scavenger receptor class B type 1(SR-B1)proteins,which act as host cofactors of viral entry,were identified to be the direct targets of 6b against ***,6b may deactivate the TMPRSS2 by inducing a change in protein conformation,rather than binding to its catalytic center,thus suppressing the viral membrane ***,our study provided key scientific data for the development of aloperine derivatives into a new class of antiviral candidates against humanβ-coronavirus,including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).

关键词： Aloperine SARS-CoV-2 TMPRSS2 SR-B1 Synthesis

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单细胞转录组学细胞动态分化数据模拟算法的比较与评估

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重庆师范大学学报（自然科学版） 2024年第1期41卷 125-132页

作者：朵泓睿李映红李勃重庆师范大学生命科学学院重庆401331 重庆邮电大学生物信息学院重庆400065

对9种单细胞转录组学(single cell RNA sequencing,scRNA-seq)细胞动态分化数据模拟算法进行系统性地比较和评估,为算法的开发者和用户提供可靠的参考和帮助。利用多种评价指标对上述算法在准确性、可拓展性、适用性等3个方面进行全面评... 详细信息

对9种单细胞转录组学(single cell RNA sequencing,scRNA-seq)细胞动态分化数据模拟算法进行系统性地比较和评估,为算法的开发者和用户提供可靠的参考和帮助。利用多种评价指标对上述算法在准确性、可拓展性、适用性等3个方面进行全面评估,并对运行时间和内存消耗情况进行建模预测。结果显示:9种被评估的算法均不能在数据特征与拓扑结构这2个方面同时有完美的表现;算法Dyngen虽然能模拟与参考数据拓扑结构和细胞分化轨迹相似度较高的数据,但是它的运行时间较长且内存消耗过大;将近一半的算法还需要及时更新版本信息并维护相关功能。用户在使用scRNA-seq细胞动态分化数据模拟算法时应综合考虑不同的使用场景和特点来选择最适合的模拟算法。

关键词：单细胞转录组学动态分化数据模拟算法评估

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水电站运行标准化与智能化监测技术的创新与实践

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中国高新科技 2024年第9期 58-60页

作者：李英鸿国能长源恩施水电开发有限公司湖北恩施445000

研究水电站运行标准化与智能化监测技术,旨在提高水电站的运行效率、降低事故风险、实现经济效益最大化。通过本研究,可高效规范水电站运行管理流程,提高管理水平和运维效率。最终目的为实现水电站的智能化监测和管理,实时掌握水电站的... 详细信息

研究水电站运行标准化与智能化监测技术,旨在提高水电站的运行效率、降低事故风险、实现经济效益最大化。通过本研究,可高效规范水电站运行管理流程,提高管理水平和运维效率。最终目的为实现水电站的智能化监测和管理,实时掌握水电站的运行状态,及时发现问题并采取措施加以解决。

关键词：水电站运行标准化

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基于盲样考核的高风险药品生产企业制药用水微生物质量管控模式的建立与应用

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中国现代应用药学 2024年第15期41卷 2071-2077页

作者：张林爽陈君豪李珏李樱红陶巧凤浙江省食品药品检验研究院杭州310000 国家药品监督管理局药品微生物检测与预警重点实验杭州310000

目的全面了解浙江省高风险药品生产企业制药用水微生物限度的检验能力,探讨基于盲样考核的高风险药品生产企业制药用水微生物质量监督新模式。方法借鉴实验室比对和盲样考核的手段在浙江省范围开展实验室评估,数据分析采用稳健Z比分数... 详细信息

目的全面了解浙江省高风险药品生产企业制药用水微生物限度的检验能力,探讨基于盲样考核的高风险药品生产企业制药用水微生物质量监督新模式。方法借鉴实验室比对和盲样考核的手段在浙江省范围开展实验室评估,数据分析采用稳健Z比分数法和盲样特性制定评价原则。结果共获得55家实验室总计165个检验结果,45家实验室获得满意结果,10家实验室结果偏离,7家偏离实验室结果负偏离,1家偏离实验室上报假阳性结果,2家企业2种偏离同时存在。结论90%偏离实验室存在假阴性或数值偏低风险,日常水系统微生物监测数据可能数值偏低,不能有效发现制药用水的质量风险。30%偏离实验室存在微生物污染风险。可能存在样品污染、检测环境污染和无菌操作不规范等问题。基于盲样考核的微生物质量监督新模式可以助力企业提升微生物控制能力,确保药品质量安全。

关键词：制药用水微生物限度高风险药品生产企业盲样考核实验室比对

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超/特高压直流输电工作环境中纯铜部件点蚀行为

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粉末冶金技术 2024年第1期42卷 91-96页

作者：何学敏王贵山李应宏史美娟南方电网超高压公司柳州局柳州545000 柳州职业技术学院柳州545000

超/特高压输电是实现全球能源互联的核心技术。作为应用最广泛的输电系统导体材料,铜及铜合金的耐蚀性被重点关注。在超/特高压直流输电过程中,周围环境存在较大磁场,导致铜部件的服役环境与普通输电环境不同。采用动电位极化、电化学... 详细信息

超/特高压输电是实现全球能源互联的核心技术。作为应用最广泛的输电系统导体材料,铜及铜合金的耐蚀性被重点关注。在超/特高压直流输电过程中,周围环境存在较大磁场,导致铜部件的服役环境与普通输电环境不同。采用动电位极化、电化学阻抗谱和元素分析等方法对纯铜在超/特高压环境下的电化学腐蚀行为进行了研究。结果表明:在超/特高压环境下,纯铜在3.5%NaCl溶液(质量分数)中的极限扩散电流高于无磁场条件下的极限扩散电流,并且无磁场条件下的反应电阻比施加了0.1 T磁场条件下的反应电阻明显提高。结合电化学阻抗谱、X射线衍射及元素分析可知,0.1 T磁场会使纯铜的耐蚀性降低,主要腐蚀产物为氧化亚铜。

关键词：超/特高压直流输电磁场纯铜耐蚀性电化学

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Investigation of Endwall Flow Behavior with Plasma Flow Control on a Highly Loaded Compressor Cascade

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Journal of Thermal Science 2012年第4期21卷 295-301页

作者： Xiaohu ZHAO yinghong li Yun WU Jun li Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University Xi' an 710038 China

To discover the flow behavior in the endwall region and mechanism of plasma flow control on a highly loaded compressor cascade, distributions of static pressure coefficient, total pressure loss coefficient and streamline pat- tern were investigated. Results show that cross flow from the pressure surface to neighboring suction surface ex- ists under pitch-wise pressure gradient. The deflected endwall boundary layer flow interacts with the incoming flow, and then both of them leave off the endwall in tile form of a span-wise vortex. Effect of angle of attack on static pressure is greater than that of free stream velocity. The distinct variations of total pressure loss with end- wall actuations are mainly located within the outer verge of a triangular area with high total pressure loss. Effect of pitch-vAse actuation on separated flows is much better than that of stream-wise actuation, and both enhance with the increase of angle of attack and actuation strength. An efficient method for plasma flow control in the endwall region is the increase of actuation strength, such as adjusting discharge voltage or changing plasma power supply.

关键词： plasma flow control compressor cascade endwall region vortex

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Numerical Investigation of Flow Separation Control on a Highly Loaded Compressor Cascade by Plasma Aerodynamic Actuation

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Chinese Journal of Aeronautics 2012年第3期25卷 349-360页

作者： ZHAO Xiaohu li yinghong WU Yun ZHU Tao li Yiwen Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038China

To discover the characteristic of separated flows and mechanism of plasma flow control on a highly loaded compressor cascade, numerical investigation is conducted. The simulation method is validated by oil flow visualization and pressure distribution. The loss coefficients, streamline patterns, and topology structure as well as vortex structure are analyzed. Results show that the numbers of singular points increase and three pairs of additional singular points of topology structure on solid surface generate with the increase of angle of attack, and the total pressure loss increases greatly. There are several principal vortices inside the cascade passage. The pressure side leg of horse-shoe vortex coexists within a specific region together with passage vortex, but finally merges into the latter. Corner vortex exists independently and does not evolve from the suction side leg of horse-shoe vortex. One pair of radial coupling-vortex exists near blade trailing edge and becomes the main part of backflow on the suction surface. Passage vortex interacts with the concentrated shedding vortex and they evolve into a large-scale vortex rotating in the direction opposite to passage vortex. The singular points and separation lines represent the basic separation feature of cascade passage. Plasma actuation has better effect at low freestream velocity, and the relative reductions of pitch-averaged total pressure loss coefficient with different actuation layouts of five and two pairs of electrodes are up to 30.8% and 26.7% while the angle of attack is 2~. Plasma actuation changes the local topology structure, but does not change the number relation of singular points. One pair of additional singular point of topology structure generates with plasma actuation and one more reattachment line appears, both of which break the separation line on the suction surface.

关键词： plasma aerodynamic actuation cascade oil flow visualization topology structure vortex singular point

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