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基于多目标遗传算法的火电机组负荷频率控制方法

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科技资讯 2024年第2期22卷 81-84页

作者：关凯国家能源集团科学技术研究院有限公司江苏南京210046

常规的负荷频率控制方法以频率协调为主,调频信号指令受到阶跃响应的影响,存在一定的频率偏差,阻碍火电机组频率控制效果。因此,设计了基于多目标遗传算法的火电机组负荷频率控制方法。提取火电机组负荷一次调频特征,将高出允许合理范... 详细信息

常规的负荷频率控制方法以频率协调为主,调频信号指令受到阶跃响应的影响,存在一定的频率偏差,阻碍火电机组频率控制效果。因此,设计了基于多目标遗传算法的火电机组负荷频率控制方法。提取火电机组负荷一次调频特征,将高出允许合理范围的火电机组负荷频率进行调整,增加或减小机组功率,使其达到新的负荷平衡。基于多目标遗传构建火电机组负荷频率控制模型,以机组发电损失与经济投入作为约束条件,优化汽轮机输出功率阶跃响应速度,从而控制火电机组负荷频率。协调机组负荷频率控制分配因子,将火电机组的前馈变负荷速率进行调节,在不影响机组负荷变化率的基础上,修正负荷频率偏差。采用对比实验,验证了方法的控制效果更佳,能够应用于实际生活中。

关键词：多目标遗传算法火电机组负荷频率控制方法

基于现场监测与数值模拟结合的采动诱发围岩失稳与地表沉降研究

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东北大学学报（自然科学版） 2024年第2期45卷 234-243页

作者：王雨萌关凯朱万成刘洪磊东北大学资源与土木工程学院辽宁沈阳110819

基于3Dmine与无人机倾斜摄影技术建立集成真实地表地貌、矿体及巷道的三维地质模型,结合Rhino6-FLAC3D建立矿体回采数值计算模型,对浅部岩层移动和地表变形的影响进行模拟分析,结合InSAR地表变形监测数据对模拟结果的有效性进行对比验... 详细信息

基于3Dmine与无人机倾斜摄影技术建立集成真实地表地貌、矿体及巷道的三维地质模型,结合Rhino6-FLAC3D建立矿体回采数值计算模型,对浅部岩层移动和地表变形的影响进行模拟分析,结合InSAR地表变形监测数据对模拟结果的有效性进行对比验证。结果表明:模拟结果与InSAR地表变形监测数据具有较好的一致性,表明基于多手段的数值建模计算与现场监测数据相结合的分析方法的有效性;对空场采矿法残留的采空区采用废石充填能够在有效控制空区围岩塑性区发展基础上维持充填体稳定性;矿区深部矿体的回采与充填可能对浅部已充填采场围岩的稳定性产生一定影响,浅部已充填采场受扰动严重程度与深部作业区域距离呈负相关;由InSAR监测数据和数值模拟结果可知,深部矿体回采扰动和浅部空区二次破坏对地表沉降影响较小.

关键词：地表变形采空区数值模拟充填体 InSAR监测

Dynesys dynamic stabilization system for the lumbar degenerative disease： a preliminary report from China

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Chinese Medical Journal 2013年第22期126卷 4265-4269页

作者： LI Hai-peng LI Fang guan kai ZHAO guang-ming SHAN Jian-lin SUN Tian-sheng Department of Orthopedics Beijing Army General Hospital Beijing 100700 China Chinese People's Liberation Army Medical School Beijing 100853 China

Background Dynesys dynamic stabilization system in 2007. Therefore, it was a new technique for Ch about Dynesys in China. The objective of this study degenerative disease in China. was first implanted in patients in 1994, and introduced to China nese orthopedics and hence necessary to collect clinical data was to report the preliminary results of Dynesys for the lumbar Methods Twenty-seven patients were treated with the Dynesys between July 2007 and January 2009. The diagnosis included degenerative spondylolisthesis （12 cases）, degenerative spinal stenosis （nine cases）, and lumbar intervertebral disc herniation （six cases）. Back pain and leg pain were evaluated using 100-mm visual analog scales （VAS）. The Oswestry Disability Index （ODI） was used to evaluate the patients＇ function. The intervertebral disc height and range of motion at the operative level were taken on radiographs. Results All the patients were followed-up, with an average of （22.40±4.23） months （range 15±32 months）. VAS of back pain and leg pain were improved significantly （P 〈0.05） at foUow-up. The ODI scores were reduced from （62.58±12.01）% preoperatively to （15.01±5.71）% at follow-up （P 〈0.05）. The preoperative mean height of the intervertebral disc was （11.21±1.58） mm （range 8.5±13.8 mm） and mean was （10.10±1.78） mm （range 7.0±13.4 mm） at follow-up （P 〈0.05）. The mean range of motion of the implanted segment was （6.00±1.79）° （range 2.5-9.3°） preoperatively and （5.47±1.27）° （range 2.9±7.8°） at follow-up （P=0.11）. Conclusions The preliminary results of Dynesys for the lumbar degenerative disease in China are similar to the published results of other countries. It can significantly improve the clinic symptoms and preserved motion at the level of implantation. However, the long-term follow-up data need to be collected.

关键词： lumbar degenerative disease dynamic stabilization Dynesys China

Dilute long period stacking/order(LPSO)-variant phases along the composition gradient in a Mg-Ho-Cu alloy

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Journal of Magnesium and Alloys 2022年第6期10卷 1573-1580页

作者： kai guan Daisuke Egusa Eiji Abe Department of Materials Science and Engineering The University of TokyoTokyo 113-8656Japan Research Center for Structural Materials National Institute for Materials ScienceTsukuba 305-0047Japan

We have systematically investigated the microstructures of as-cast Mg_(97.49)Ho_(1.99)Cu_(0.43)Zr_(0.09)alloy by atomic resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM), revealing the coexistence of 18R, 14H and 24R long period stacking/order(LPSO) phases with fully coherent interfaces along step-like composition gradient in a blocky intermetallic compound distributed at grain boundary. The short-range order(SRO) L1_(2)-type Cu_(6)Ho_(8)clusters embedded across AB’C’A-stacking fault layers are directly revealed at atomic scale. Importantly, the order degree of SRO clusters in the present dilute alloy is significant lower than previous 6M and 7M in-plane order reported in ternary Mg-TM(transition metal)-RE(rare earth) alloys, which can be well matched by 9M in-plane order. This directly demonstrates that SRO in-plane L1_(2)-type clusters can be expanded into more dilute composition regions bounded along the definite TM/RE ratio of 3/4. In addition, the estimated chemical compositions of solute enriched stacking fault(SESF) in all LPSO variants are almost identical with the ideal SESF composition of 9M in-plane order, regardless of the type of LPSO phases. The results further support the viewpoint that robust L1_(2)-type TM_(6)RE_(8)clusters play an important role in governing LPSO phase formation.

关键词： Magnesium alloys Long period stacking/order(LPSO)phases Short-range order(SRO)clusters High-angle annular dark field scanning transmission electron microscopy(HAADF-STEM)

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航空信息网络服务功能链请求调度策略

兵工学报 2024年第7期45卷 2306-2317页

作者：曹代詹思瑜郝鑫胜关楷付皓通电子科技大学信息与通信工程学院四川成都611731 电子科技大学智能计算研究院四川成都611731 93303部队辽宁沈阳110000 95859部队甘肃酒泉735000

为解决航空信息网络场景下业务突发、拓扑结构动态变化以及资源有限所带来的资源利用效率低下问题,针对服务功能链请求(Service Function Chain Requirement,SFCR)高效调度的难题,提出一种网络功能虚拟化的服务功能链调度算法。算法依据... 详细信息

为解决航空信息网络场景下业务突发、拓扑结构动态变化以及资源有限所带来的资源利用效率低下问题,针对服务功能链请求(Service Function Chain Requirement,SFCR)高效调度的难题,提出一种网络功能虚拟化的服务功能链调度算法。算法依据SFCR与平台的相关性进行映射,提高服务器处理效率并有效减少虚拟网络功能实例化数量及整合平台资源;综合考虑时延和流量影响对网络功能实例进行整合迁移,降低网络能耗同时提升网络资源利用率。仿真结果表明,在满足时延需求条件下,新方法在运行平台数量、SFCR接受率、网络资源消耗等方面具有较好的优化性能,适用于解决航空信息网络场景下的SFCR调度问题。

关键词：航空信息网络网络功能虚拟化服务功能链服务功能链请求调度网络功能实例

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激光增材制造铜铬锆合金研究进展:成形行为、微观组织和综合性能(特邀)

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中国激光 2024年第4期51卷 141-159页

作者：陈兴宇李昊陈乔雨徐海升谢凡轩李正黄田野关凯尹作为郝亮殷杰中国地质大学(武汉)珠宝学院湖北武汉430074 中国地质大学(武汉)先进制造研究所湖北武汉430074 湖北三江航天江北机械工程有限公司湖北孝感432000 中国地质大学(武汉)机械与电子信息学院湖北武汉430074 鑫精合激光科技有限公司北京102200

铜铬锆(CuCrZr)作为沉淀硬化合金,以其良好的耐热性、耐腐蚀性以及优异的力学、电学和热学性能而被广泛应用于航空航天、核能化工等领域。然而,CuCrZr是当前激光增材制造(LAM)难成形材料之一,相关研究报道还很有限。本文综述了近年来激... 详细信息

铜铬锆(CuCrZr)作为沉淀硬化合金,以其良好的耐热性、耐腐蚀性以及优异的力学、电学和热学性能而被广泛应用于航空航天、核能化工等领域。然而,CuCrZr是当前激光增材制造(LAM)难成形材料之一,相关研究报道还很有限。本文综述了近年来激光粉末床熔融(L-PBF)制备CuCrZr合金的研究进展,重点探究了绿激光与近红外激光对成形质量的影响规律,分析了热处理及构建方向与微观组织、力学性能的内在联系,并研究了热处理对于电学、热学性能的强化机制。近红外激光制备样品的致密度波动范围大(95.5%~99.9%),绿激光制备样品的整体致密度较低但波动范围较小(96.5%~98.5%),工艺参数仍有优化空间。合金的微观组织和综合性能都存在各向异性,即沿水平方向的晶粒细小,沿垂直方向的晶粒为柱状晶粒。固溶处理会使合金的熔池边界消失并改变晶粒形态,时效处理导致合金产生沉淀并改变晶粒取向。500℃左右处理1~2 h的直接时效处理对力学性能的提升最大,时效处理通过降低位错密度、减少热残余应力和促进沉淀物的形成,显著增强了合金的力学性能。对电学、热学性能提升最大的热处理条件为950~1000℃的固溶退火处理1 h+500℃左右的时效硬化处理1~3 h,这是因为固溶退火+时效硬化处理降低了位错密度和残余应力,并产生了有益的沉淀物。本文总结了L-PBF制备CuCrZr合金的成形行为、微观组织和综合性能的研究进展,并对其研究前景和发展方向进行了展望。

关键词：激光增材制造铜铬锆合金成形行为微观组织综合性能

大数据驱动下航空类课程过程性考核评价研究——以《民航概论》课程为例

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交通企业管理 2024年第4期39卷 118-121页

作者：胡观凯钟建华四川工业科技学院中国民航第二研究所

现代化技术的发展给如今的教学模式带来了巨大变革,教学从传统的线下教学转为“线上+线下”混合式教学模式。这种教学方式不仅能提高教师的教学效率,还能激发学生的学习兴趣,甚至将大量信息化课程资源通过线上线下的教学方式带入课堂。... 详细信息

现代化技术的发展给如今的教学模式带来了巨大变革,教学从传统的线下教学转为“线上+线下”混合式教学模式。这种教学方式不仅能提高教师的教学效率,还能激发学生的学习兴趣,甚至将大量信息化课程资源通过线上线下的教学方式带入课堂。在此教学模式下,航空类课程的教学考核评价就不能再沿用传统的教学评价模式,传统的评价没有包含线上教学环节。大数据的发展给航空类课程的过程性考核评价带来了契机。在大数据驱动下可以实现线上课程数据和线下课程数据的全面整合,从而达到航空课程“课前+课中+课后”全过程性的考核。

关键词：航空类课程过程性考核大数据驱动民航概论混合式教学

Eosinophilic gastroenteritis: Pathogenesis, diagnosis, and treatment

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Chinese Medical Journal 2023年第8期136卷 899-909页

作者： kaiwen Li Gechong Ruan Shuang Liu Tianming Xu kai guan Ji Li Jingnan Li Department of Gastroenterology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100005China Key Laboratory of Gut Microbiota Translational Medicine Research Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100005China Department of Allergy Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100005China

Eosinophilic gastroenteritis(EGE)is a gastrointestinal disorder of unclear etiology that is characterized by eosinophilic infiltration of the stomach and small intestine,and consists of mucosal,muscular,and serosal subtypes.Eosinophilic infiltration of the gastrointestinal tract is a fundamental histopathological characteristic of EGE and is driven by several T-helper type 2(Th2)-dependent cytokines and induced by food allergy.Due to the lack of a diagnostic gold standard,EGE has a high rate of delayed diagnosis or misdiagnosis.However,several new diagnostic strategies have been developed,such as novel genetic biomarkers and imaging tests.Although dietary therapy and corticosteroids remain the common choices for EGE treatment,recent decades have seen the emergence of novel treatment alternatives,such as biologics that target particular molecules involved in the pathogenic process.Preliminary investigations and clinical trials have demonstrated the efficacy of biologics and provided additional insights for the era of refractory or corticosteroid-dependent EGE biologics.

关键词： Eosinophilic gastroenteritis Pathogenesis Diagnosis Treatment

Hardening effect and precipitation evolution of an isothermal aged Mg-Sm based alloy

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Journal of Magnesium and Alloys 2023年第12期11卷 4619-4627页

作者： kai guan Chuang Li Zhizheng Yang Yongsen Yu Qiang Yang Wenwen Zhang Zhiping guan Cheng Wang Min Zha Huiyuan Wang Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and Engineering Jilin UniversityChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Energy and Hydrocarbon Chemistry Graduate School of EngineeringKyoto UniversityNishikyo-kuKyoto 615-8510Japan

The age-hardening behavior and precipitation evolution of an isothermal aged Mg-5Sm-0.6Zn-0.5Zr(wt.%) alloy have been systematically investigated by means of transmission electron microscopy(TEM) and atomic-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM). The Vickers hardness of the present alloy increases first and then decreases with ageing time. The sample aged at 200 ℃ for 10 h exhibits a peak-hardness of 90.5 HV. In addition to the dominant β_(0)’ precipitate(orthorhombic,a = 0.642 nm, b = 3.336 nm and c = 0.521 nm) formed on {11-20}α planes, a certain number of γ’’ precipitate(hexagonal, a = 0.556 nm and c = 0.431 nm) formed on basal planes are also observed in the peak-aged alloy. Significantly, the basal γ’’ precipitate is more thermostable than prismatic β_(0)’ precipitate in the present alloy. β_(0)’ precipitates gradually coarsened and were even likely to transform into β_(1) phase(face centered cubic, a = 0.73 nm) with the increase of ageing time, which accordingly led to a gradual decrease in number density of precipitates and finally resulted in the decreased hardness and mechanical property in the over-aged alloys.

关键词： Magnesium alloys Ageing treatment Microstructure characterization Age-hardening effect Precipitates