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面向可持续生产中多任务调度的双重增强模因算法

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自动化学报 2024年第4期50卷 731-744页

作者：卢弘王耀南乔非方遒湖南大学电气与信息工程学院长沙410082 同济大学电子与信息工程学院上海201804

从经济、环境和社会3个维度,全面提升生产调度方案的可持续性具有重要意义.针对并行机生产场景,建立考虑机器指派、加工顺序、人员安排以及开关机控制等4种决策任务的调度模型.为实现对复杂决策空间的高效寻优,提出一种融合两种局部优... 详细信息

从经济、环境和社会3个维度,全面提升生产调度方案的可持续性具有重要意义.针对并行机生产场景,建立考虑机器指派、加工顺序、人员安排以及开关机控制等4种决策任务的调度模型.为实现对复杂决策空间的高效寻优,提出一种融合两种局部优化策略的双重增强模因算法(Dual-enhanced memetic algorithm, DMA)求解模型.从随机更新角度,针对不同决策任务,构造单步变邻域搜索(One-step variable neighborhood search, 1S-VNS)策略.从定向优化角度,分析目标和关键任务之间的匹配关系,提出一种可持续目标导向策略(Sustainable goals-oriented strategy, SGS).考虑到两种优化策略的不同特点,单步变邻域搜索策略作用于整个种群,目标导向策略强化种群中的精英个体,实现对输出解集的双重优化.仿真实验结果表明,双重优化策略能有效地增强算法性能,并且所提算法在非支配解的多样性和收敛性上具有优越性.

关键词：可持续生产多任务调度优化策略模因算法

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大幅宽面阵相机多片探测器影像拼接方法

航天返回与遥感 2024年第4期45卷 48-57页

作者：周楠邱庞合北京空间机电研究所北京100094

大幅宽面阵相机通常采用多片探测器拼幅成像的方式来增大幅宽。为了提高数据的使用效率,用户要求提供几何无损和视觉无缝的拼接产品。由于分片探测器间重叠区域小甚至无重叠区,拼接后影像畸变增大等原因,传统像方拼接方法难以适用。针... 详细信息

大幅宽面阵相机通常采用多片探测器拼幅成像的方式来增大幅宽。为了提高数据的使用效率,用户要求提供几何无损和视觉无缝的拼接产品。由于分片探测器间重叠区域小甚至无重叠区,拼接后影像畸变增大等原因,传统像方拼接方法难以适用。针对此问题,文章提出一种基于传感器校正的大幅宽面阵相机多片探测器影像高精度几何拼接方法。该方法首先根据卫星相机分片探测器的物理结构及其成像几何特性,虚拟一个完全理想的无畸变面阵影像,影像覆盖范围与原始分片探测器影像覆盖范围相同;在严格标定分片探测器像元指向的基础上,建立虚拟影像与原始分片影像的像点坐标换算关系,并将原始分片影像的像点灰度值赋给虚拟影像对应像点,进而实现对分片影像的无缝拼接和畸变校正。经对仿真数据和在轨数据的试验验证,结果表明:对于不同探测器拼接方式和搭接区重叠情况,文章中所提方法可获得视觉无缝和几何无损的拼接影像,影像的片间拼接精度和影像内部几何畸变均优于1个像素。

关键词：传感器校正影像拼接面阵相机静止轨道卫星

Experimental investigation of closed-loop active control to modulate coherent structures by mu-level method

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Chinese Physics B 2024年第7期33卷 408-417页

作者：白建侠范子椰姜楠李秋营郑小波 Department of Mathematics Tianjin Renai CollegeTianjin 301636China Institute of Mechanics Department of MechanicsSchool of Mechanical EngineeringTianjin UniversityTianjin 300354China College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300354China

The experimental research on zero-net-mass-flux jet closed-loop active control was conducted in the wind *** mu-level method successfully detected burst events of the coherent structures. The streamwise velocity signals in the turbulent boundary layer were measured by HWA. The drag reduction rate of 16.7% is obtained comparable to that of the open-loop control and saves 75% of the input energy at the asynchronous 100 V/160 Hz control case, which reflects the advantages of the closed-loop control. The experimental findings indicate that the intensity increases in the near-wall *** perturbation of the PZT vibrators on the skewness factor is concentrated in the region y+< 60. The generation of highspeed fluids is depressed and the downward effect of high-speed fluids weakens. The alteration of energy distribution and the discernible impact of modulation between structures of varying scales are observed. The correlation coefficient exhibits a strong positive correlation, which indicates that the large-scale structures produce modulation effect on small-scale *** occurrence of burst events is effectively suppressed. The disturbance has the characteristics of stable periodicity,positive and negative symmetry, low intermittency, and high pulsation strength. The conditional phase waveform shows that the fluctuation amplitude increases, indicating amplitude modulation effects on coherent structures.

关键词： turbulent boundary layer(TBL) burst event coherent structures mu-level method

The effects of population aging on industrial structure upgrading:Empirical analysis of provincial and threshold characteristics in China

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Chinese Journal of Population,Resources and Environment 2024年第3期22卷 356-366页

作者： mao Hu Linyu Xiao Hong qiu School of Management Xihua UniversityChengdu 610039China Research Institute of International Economics and Management Xihua UniversityChengdu 610039China

Global population aging trends are intensifying,presenting multifaceted economic and social challenges for countries *** the world’s largest developing country,China has entered a phase of extreme demographic aging,posing significant questions about its impact on the ongoing upgrading of industrial *** does this demographic shift influence the upgrading of industrial structures,and does technological innovation mitigate or exacerbate this impact?The empirical results indicate that population aging impedes upgrading the industrial structure,while technological innovation positively affects the relationship between the ***,using technological innovation as a threshold variable,the impact of population aging on industrial structure upgrading evolves in a“gradient”manner from“impediment”to“insignificant”to“promotion”as the technological innovation levels *** findings offer practical guidance for tailoring industrial policies to different stages of technological advancement.

关键词： Population aging Technological innovation level Industrial structure upgrading Panel threshold models Instrumental variable method

循环改进健康教育对人工流产患者术后生殖保健及创伤后成长的影响

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中国临床研究 2024年第9期37卷 1448-1452页

作者：冒文盈鲁南南京医科大学第一附属医院生殖中心江苏南京210029

目的探讨对进行人工流产的患者使用循环改进健康教育是否可以改善其创伤后恢复状况及生殖保健结局。方法选取2022年2月至12月南京医科大学第一附属医院收治的人工流产患者144例作为研究对象,用数字随机法将患者分为研究组(n=72)和对照组... 详细信息

目的探讨对进行人工流产的患者使用循环改进健康教育是否可以改善其创伤后恢复状况及生殖保健结局。方法选取2022年2月至12月南京医科大学第一附属医院收治的人工流产患者144例作为研究对象,用数字随机法将患者分为研究组(n=72)和对照组(n=72),对照组患者采用常规健康教育方法,研究组在对照组护理方案的基础上接受PDCA循环改进健康教育方法,比较两组患者干预后创伤后成长评定量表(PTGI)评分情况、并发症发生情况、术后重复流产率及术后备孕成功率,分析循环改进健康教育方法的重要性。结果干预后,与对照组比较,研究组患者PTGI量表中新的可能性、个人力量、精神变化和对生活的欣赏四个维度评分及总分,以及术后6个月长效可逆避孕措施使用率增高(P<0.05),术后辅助生殖就诊率增高(95.24%vs 72.73%,χ^(2)=7.990,P=0.005),新发不孕症率降低(50.00%vs 84.38%,χ^(2)=9.268,P=0.002)。结论PDCA循环改进健康教育能够有效改善人工流产患者生殖保健意识、改善创伤后成长,减少不孕不育的发生,有较高的应用价值。

关键词：生殖保健人工流产 PDCA循环健康教育创伤后成长

GaInX_3(X=S,Se,Te):Ultra-low thermal conductivity and excellent thermoelectric performance

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Chinese Physics B 2024年第8期33卷 460-465页

作者：段志福丁长浩丁中科肖威华谢芳罗南南曾犟唐黎明陈克求 Department of Physics School of Physics and ElectronicsHunan UniversityChangsha 410082China College of Physical Science and Engineering Technology Yichun UniversityYichun 336000China

Seeking intrinsically low thermal conductivity materials is a viable strategy in the pursuit of high-performance thermoelectric ***,by using first-principles calculations and semiclassical Boltzmann transport theory,we systemically investigate the carrier transport and thermoelectric properties of monolayer Janus GaInX_(3)(X=S,Se,Te).It is found that the lattice thermal conductivities can reach values as low as 3.07 W·m^(-1)·K^(-1),1.16 W·m^(-1)·K^(-1)and 0.57 W·m^(-1)·K^(-1)for GaInS_(3),GaInSe_(3),and GaInTe_(3),respectively,at room *** notably low thermal conductivity is attributed to strong acoustic-optical phonon coupling caused by the presence of low-frequency optical phonons in GaInX_(3) ***,by integrating the charac teristics of electronic and thermal transport,the dimensionless figure of merit ZT can reach maximum values of 0.95,2.37,and 3.00 for GaInS_(3),GaInSe_(3),and GaInTe_(3),*** results suggest that monolayer Janus GaInX_(3)(X=S,Se,Te)is a promising candidate for thermoelectric and heat management applications.

关键词： thermoelectric performance thermal conductivity Boltzmann transport two-dimensional materials

基于PCA-SVM结合共聚焦拉曼光谱的特级初榨橄榄油掺伪压榨菜籽油定量分析

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中国油脂 2024年第2期49卷 70-74页

作者：彭楠方俊毛潭北京京北职业技术学院北京101400 北方工业大学北京100144

为了促进国内橄榄油市场的健康发展,对掺伪同样存在天然类胡萝卜素的低温压榨菜籽油的特级初榨橄榄油进行了定量鉴别研究。采用共聚焦拉曼光谱技术对不同掺伪浓度油样进行测试,基于密度泛函理论对油样的拉曼光谱峰的归属进行了理论分析... 详细信息

为了促进国内橄榄油市场的健康发展,对掺伪同样存在天然类胡萝卜素的低温压榨菜籽油的特级初榨橄榄油进行了定量鉴别研究。采用共聚焦拉曼光谱技术对不同掺伪浓度油样进行测试,基于密度泛函理论对油样的拉曼光谱峰的归属进行了理论分析,并对拉曼光谱数据进行主成分分析(PCA),然后利用支持向量机(SVM)构建PCA-SVM模型。另外,对PCA-SVM模型的检出限进行了研究。结果表明:特级初榨橄榄油与低温压榨菜籽油的拉曼光谱存在一定差异,最明显的光谱差异主要集中在谱峰1008、1161、1528 cm^(-1)和谱段2800~3000 cm^(-1)内,与密度泛函理论对不同油样拉曼光谱峰的分析一致;不考虑类胡萝卜素特征信号建立的PCA-SVM模型决定系数大于0.989,均方根误差小于2.990%,检出限为2%(低温压榨菜籽油体积分数);在特级初榨橄榄油掺伪定量分析中,考虑类胡萝卜素的特征信号有助于提高模型预测精度,但仅限于掺伪低价植物油中无类胡萝卜素存在的情况;PCA-SVM模型在不考虑类胡萝卜素特征信号的情况下依然具有良好的定量预测效果。综上,所建立的PCA-SVM模型可以用于掺伪2%以上低温压榨菜籽油的特级初榨橄榄油的定量鉴别。

关键词：特级初榨橄榄油低温压榨菜籽油 PCA-SVM 拉曼光谱密度泛函理论

High Temperature Iron Ethylene Polymerization Catalysts Bearing N,N,N'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir qiu-Yue Zhang Bayasgalan Ulambayar Gregory A.Solan Tong-Ling Liang Wen-Hua Sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The N,N,N'-ferrous chloride complexes,[2-{CMeN(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMeNAr)C_(5)H_(3)N]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one N-2,4-dibenzhydryl-6-fluorophenyl group,were readily synthesized from their respective unsymmetrical bis(imino)pyridines,*** identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar N-aryl *** pre-treatment with either mao or Mmao,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization with levels falling in the order:Fe4> Fe1> Fe5> Fe2> ***,Fe4/mao displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study with only a modest loss in performance at 90℃.Generally,the resulting polyethylenes were highly linear(T_(m) range:122-132℃),narrowly disperse and of low molecular weight(M_(w) range:6.73-46.04kg·mol^(-1)),with the most sterically hindered Fe3 forming the highest molecular weight polymer of the ***-group analysis by ^(1)H-and ^(13)CNMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination *** comparison with previou sly reported iron precatalysts with similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination with a fluorine as the ortho-substituents of one N-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst whilst maintaining appreciable polymer molecular weight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

Factors influencing further vertebral height loss following percutaneous vertebroplasty in osteoporotic vertebral compression fractures:A 1-year follow-up study

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World Journal of Clinical Cases 2024年第21期12卷 4609-4617页

作者： Zhong-qiu Tang Shao-Bo He Dong-Yang Yu Hai-mao Luo Xue-Hong Xing Yong-Wen Zhou Department of Spinal Surgery Affiliated Hospital of Panzhihua UniversityPanzhihua 617000Sichuan ProvinceChina Department of Shoulder and Elbow Surgery Affiliated Hospital of Panzhihua UniversityPanzhihua 617000Sichuan ProvinceChina

BACKGROUND Osteoporotic vertebral compression fractures(OVCFs)contribute to back pain and functional limitations in older individuals,with percutaneous vertebroplasty(PVP)emerging as a minimally invasive ***,further height loss post-PVP prompts investigation into contributing *** To investigate the factors associated with further height loss following PVP with cement augmentation in OVCF *** A total of 200 OVCF patients who underwent successful PVP between January 2021 and December 2022 were included in this study.“Further height loss”during 1 year of follow-up in OVCF patients with bone edema was defined as a vertical height loss of≥4 *** study population was divided into two groups for analysis:The“No Further Height Loss group(n=179)”and the“Further Height Loss group(n=21).”RESULTS In comparing two distinct groups of patients,significant differences existed in bone mineral density(BMD),vertebral compression degree,prevalence of intravertebral cleft(IVF),type of bone cement used,and cement distribution *** from binary univariate regression analysis revealed that lower BMD,the presence of IVF,cleft distribution of bone cement,and higher vertebral compression degree were all significantly associated with further height ***,the use of mineralized collagen modified-poly(methyl methacrylate)bone cement was associated with a significant reduction in the risk of further height *** multivariate regression analysis,lower BMD and the presence of IVF remained significantly associated with further height *** Further height loss following PVP in OVCF patients is influenced by a complex interplay of factors,especially lower BMD and the presence of *** findings underscore the importance of assessing and managing these factors when addressing height loss following PVP in OVCF patients.

关键词： Percutaneous vertebroplasty Osteoporotic vertebral compression fractures Further height loss Bone mineral density Intravertebral cleft