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基于粒子群优化支持向量机的纱线质量预测

棉纺织技术 2024年第4期52卷 16-22页

作者：章军辉陈明亮郭晓满付宗杰王静贤常熟理工学院江苏苏州215500 中国科学院大学北京100049 无锡物联网创新中心有限公司江苏无锡214029 江苏省物联网创新中心昆山分中心江苏苏州215347

针对复杂纺纱过程中成纱质量预测精度不足以及深度学习对庞大数据集依赖性的缺陷,提出一种基于粒子群算法优化支持向量机的小样本成纱质量预测方法。首先,对原始数据集样本序列进行灰色关联预处理,按照关联度大小进行排序,再结合先验知... 详细信息

针对复杂纺纱过程中成纱质量预测精度不足以及深度学习对庞大数据集依赖性的缺陷,提出一种基于粒子群算法优化支持向量机的小样本成纱质量预测方法。首先,对原始数据集样本序列进行灰色关联预处理,按照关联度大小进行排序,再结合先验知识库筛选出主要的原棉纤维指标;其次,针对小样本预测问题,建立了线性核、多项式核、高斯核以及自适应带宽RBF核等不同核函数支持向量回归(SVR)预测模型;最后,采用粒子群优化(PSO)算法对高斯核SVR模型的超参数(正则化系数和带宽调节参数)进行辨识,设计一种综合适应度函数与线性递减惯性权重策略,用以提高PSO算法的寻优能力。仿真结果表明:PSO优化高斯核SVR模型对不同成纱质量指标有较好的预测效果,其平均相对误差不超过2%。认为:PSO优化高斯核SVR模型对成纱质量指标的预测误差较低,具有良好的适应性。

关键词：支持向量机粒子群优化灰色关联纱线质量预测核函数

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基于粒子群萤火虫混合算法的计算机辅助配棉

棉纺织技术 2024年第10期52卷 47-53页

作者：陈明亮章军辉丁羽璇刘禹希刘俊泽常熟理工学院江苏苏州215500 中国科学院大学北京100049 无锡物联网创新中心有限公司江苏无锡214029 江苏省物联网创新中心昆山分中心江苏苏州215347

为促进棉纺企业精细化管理水平和生产效益的提升,提出一种粒子群萤火虫混合算法的计算机辅助配棉方法。首先,构造混和棉成本最小和混和棉综合质量指标最优的多目标优化函数,建立库存、总重量、原棉种类及质量指标边界等多约束条件,按照... 详细信息

为促进棉纺企业精细化管理水平和生产效益的提升,提出一种粒子群萤火虫混合算法的计算机辅助配棉方法。首先,构造混和棉成本最小和混和棉综合质量指标最优的多目标优化函数,建立库存、总重量、原棉种类及质量指标边界等多约束条件,按照线性加权方式将多目标模型转化为单目标模型。其次,对粒子群和萤火虫群进行分阶段初始化,设计一种学习因子动态调整和非线性递减惯性权重策略用以提高粒子群算法的综合寻优能力,并采用自适应移动步长更新萤火虫个体位置。最后,使用粒子群、萤火虫及粒子群萤火虫混合算法对配棉模型进行求解。试验结果表明:3种配棉算法均展现出良好的求解可行性,所得混和棉质量指标的综合绝对误差分别为0.0268、0.0240、0.0281,皆处于较低水平;并且粒子群萤火虫混合算法在成本节约方面更具优势,其配棉的总成本相比粒子群算法、萤火虫算法分别降低了1.20%、2.27%。

关键词：计算机辅助配棉混合算法粒子群优化算法萤火虫群优化算法线性加权法

2017—2021年南宁市男性流动人口高危性行为安全套使用情况分析

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职业与健康 2024年第4期40卷 484-489,495页

作者：何波覃美萍农丽萍汤洪洋刘君辉黄智勇南宁市疾病预防控制中心结核病防制科广西南宁530023 南宁市青秀区疾病预防控制中心性病与艾滋病防制科广西南宁530021

目的了解南宁市男性流动人口高危性行为、安全套使用情况及影响因素,为开展流动人口艾滋病防治工作提供参考依据。方法采用流行病学与血清学相结合的方法,于2017—2021年每年的4—7月,在南宁市邕宁区8个建筑工地对年龄为15~65岁的非南... 详细信息

目的了解南宁市男性流动人口高危性行为、安全套使用情况及影响因素,为开展流动人口艾滋病防治工作提供参考依据。方法采用流行病学与血清学相结合的方法,于2017—2021年每年的4—7月,在南宁市邕宁区8个建筑工地对年龄为15~65岁的非南宁市户籍的男性流动人口进行问卷调查,分析其中高危性行为、安全套使用情况及影响因素。结果共调查1739名男性流动人口,答对≥6题的艾滋病知识总知晓率、最近1年的商业性行为和临时性行为总的发生率分别为97.18%(1690/1739)、10.75%(187/1739)和7.42%(129/1739)。2017—2021年南宁市男性流动人口答对≥6题的知晓率(2018年最低[92.72%(280/302)])、商业性行为(2021年最高[27.75%(111/400)],2020年最低[2.62%(9/343)])和临时性行为(2021年最高[16.00%(64/400)],2020年最低[1.17%(4/343)])的发生率均出现波动现象,差异均有统计学意义(χ^(2)=39.37、179.96、65.16,均P<0.01)。最近1年的每次商业性行为和每次临时性行为总的安全套坚持使用率分别为87.17%(163/187)和57.36%(74/129)。2017—2021年每次商业性行为[2019年最低为53.85%(7/13)]和每次临时性行为[2018年最低为17.65%(3/17)]的安全套坚持使用率均出现波动现象,差异也均有统计学意义(χ^(2)=12.04、15.18,均P<0.01)。不知晓艾滋病知识(OR=0.087,95%CI:0.014~0.551)是男性流动人口每次商业性行为坚持使用安全套的危险因素。外省户籍(OR=3.028,95%CI:1.444~6.352)是男性流动人口每次临时性行为坚持使用安全套的保护因素。结论2017—2021年南宁市邕宁区男性流动人员艾滋病知识知晓率处于较高水平,但高危性行为发生率仍较高,安全套使用率较低。仍需加大力度有针对性开展艾滋病性病相关知识,并从行为上加强预防干预。

关键词：男性流动人口高危性行为安全套使用影响因素

Optical transmitter module with hybrid integration of DFB laser diode and proton-exchanged LiNbO_(3)modulator chip

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Journal of Semiconductors 2022年第6期43卷 34-39页

作者： Xuyang Wang He Jia junhui Li Yumei Guo Yu Liu State Key Laboratory on Integrated Optoelectronics Institution of SemiconductorsChinese Academy of SciencesBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China Beijing Shiweitong Science&Technology Co. Ltd.Beijing 100176China

In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical *** whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output *** a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was *** optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured.

关键词： optical transmitter module hybrid integration DFB laser chip LiNbO3 modulator chip

Nondegenerative ML-sequences over ring z/(2~e)

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Chinese Science Bulletin 1999年第17期44卷 1557-1561页

作者： YANG junhui and zHAI QibinInstitute of Software , Chinese Academy of Sciences , Beijing 100080, China State Key Laboratory of Information Security , Beijing 100080, China Chinese Acad Sci Inst Software Beijing 100080 Peoples R China State Key Lab Informat Secur Beijing 100080 Peoples R China

The so-called quasi-period of an ML-sequence has been introduced. It is noted that an ML-sequence may degenerate in the sense that it has the quasi-period shorter than its period, and the problem of constructing the n... 详细信息

关键词： nondegenerate ML-sequence quasi-period.

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台车式热处理炉热处理过程模拟与分析

佳木斯大学学报（自然科学版） 2024年第2期42卷 72-75,105页

作者：赵金福徐明哲孔玲王军辉郭华楼王玉辉燕山大学国家冷轧板带装备及工艺工程技术研究中心河北秦皇岛066004 燕山大学机械工程学院河北秦皇岛066004 中钢集团邢台机械轧辊有限公司河北邢台054025

热处理是轧辊产品生产过程中至关重要的环节,合理的热处理工艺对轧辊质量具有重要影响。采用数值模拟的方法,系统研究了热处理炉中轧辊不同摆放位置对炉内流场、温度场以及轧辊表面温度场的影响,为制定轧辊的精准热处理工艺,以及提高轧... 详细信息

热处理是轧辊产品生产过程中至关重要的环节,合理的热处理工艺对轧辊质量具有重要影响。采用数值模拟的方法,系统研究了热处理炉中轧辊不同摆放位置对炉内流场、温度场以及轧辊表面温度场的影响,为制定轧辊的精准热处理工艺,以及提高轧辊产品质量奠定基础。

关键词：台车式热处理炉热处理温度场流场轧辊

Integration of Prealbumin into Child-Pugh Classification Improves Prognosis Predicting Accuracy in HCC Patients Considering Curative Surgery

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Journal of Clinical and Translational Hepatology 2018年第4期6卷 377-384页

作者： Xiajie Wen Mingjie Yao Yiwei Lu junhui Chen Jiyuan zhou Xiangmei Chen Yun zhang Weiquan Lu Xiangjun Qian Jingmin z.ao Ling zhang Shigang Ding Fengmin LU Department of Minimally Invasive Intervention Peking University Shenzhen HospitalShenzhen PKU-HKUST Medical CenterShenzhenChina Department of Microbiology&Infectious Disease Center School of Basic Medical SciencesPeking University Health Science CenterBeijingChina Department of Hepatopancreatobiliary Surgery Henan Cancer Hospital Affiliated to Zhengzhou UniversityZhengzhouChina Department of Pathology and Hepatology Beijing 302 HospitalBeijingChina Peking University Third Hospital Department of GastroenterologyBeijingChina University of North Carolina-Eshelman School of Pharmacy Chapel HillNCUSA

Background and Aims:The poor outcomes of hepatocellular carcinoma(HCC)patients may be due to not only malignant tumors but also limited liver ***,as stated in major guidelines,only patients with relatively normal liver function(Child-Pugh A)would be referred for curative *** so,the postsurgery survival rate of patients is still extremely *** curative resection may benefit most *** study aimed to improve the prognosis predicting accuracy of the Child-Pugh scoring ***:This study included two cohorts:cohort A being composed of 613 HCC patients,with a 23-month median postsurgery follow-up time;and cohort B being composed of 554 tumor-free chronic liver disease ***-Meier test and Cox model were used for survival ***-samples t test or one-way ANOVA was used to test the differences between different ***:Serum prealbumin levels were found inversely correlated with worsening of flbrotic scores(r=-0.482,pzard ratio of 0.731(p=0.001).By integrating prealbumin together with total bilirubin level,serum albumin concentration and prothrombin time,a modified liver disease prognosis scoring system was developed to define traditional Child-Pugh A HCC patients as Modified Child-Pugh MCP-1,MCP-2 and MCP-3,with median postsurgery overall survival times of 44.00,28.00 and 11.00 months ***:Preoperative serum prealbumin is a valuable prognosis predicting biomarker for Child-Pugh A HCC patients who may be under consideration for curative *** serum prealbumin included as one of the parameters,the MCP scoring system might improve the postsurgery survival predicting accuracy for HCC patients.

关键词： Hepatocellular carcinoma Curative resection Survival Child-Pugh prealbumin

Exceptionally high genetic variance of the doubled haploid(DH)population of poplar

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林业研究:英文版 2023年第6期34卷 1941-1950页

作者： Caixia Liu Sui Wang Yi Liu Meng Wang Erqin Fan Chen Liu Shikai zhang Chuanping Yang junhui Wang Heike W.Sederoff Xiangling You Vincent L.Chiang Su Chen Ronald R.Sederoff Guanzheng Qu College of Life Science Northeast Forestry UniversityHarbin 150040People’s Republic of China State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Soybean Biology in Chinese Ministry of Education Northeast Agricultural UniversityHarbin 150030People’s Republic of China State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Department of Plant and Microbial Biology North Carolina State UniversityRaleighNC 27695USA Forest Biotechnology Group Department of Forestry and Environmental ResourcesNorth Carolina State UniversityRaleighNC 27695USA

Doubled haploid(DH)plants have been widely used for breeding and biological research in *** ulus *** been used as model woody plant species for biological ***,the induction of DH poplar plants is onerous,and limited biological or breeding work has been carried out on DH individuals or *** this study,we provide an effective protocol for poplar haploid induction based on an anther culture method.A total of 96 whole DH plant lines were obtained using an F1hybrid of Populus simonii×*** as a donor *** phenotypes of the DH population showed exceptionally high variance when compared to those of half-sib progeny of the donor *** DH line displayed distinct features compared to those of the other DH lines or the donor ***,some excellent homozygous lines have the potential to be model plants in genetic and breeding studies.

关键词： Populus Anther culture Doubled haploid Genetic variance Flow cytometry

Friction and wear properties of copper matrix composites reinforced by tungsten-coated carbon nanotubes

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Rare Metals 2011年第6期30卷 657-663页

作者： NIE junhui JIA Xian JIA Chengchang LI Yi zHANG Yafeng SHI Na School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China China Iron ＆ Steel Research Institute Group Beijing 100081 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

Carbon nanotubes （CNTs） were coated by tungsten layer using metal organic chemical vapor deposition process with tungsten hexacarbonyl as a precursor. The W-coated CNTs （W-CNTs） were dispersed into Cu powders by magnetic stirring process and then the mixed powders were consolidated by spark plasma sintering to fabricate W-CNTs/Cu composites. The CNTs/Cu composites were fabricated using the similafprocesses. The friction coefficient and mass wear loss of W-CNTs/Cu and CNTs/Cu composites were studied. The results showed that the W-CNT content, interfacial bonding situation, and applied load could influence the friction coefficient and wear loss of W-CNTs/Cu com- posites. When the W-CNT content was 1.0 wt.%, the W-CNTs/Cu composites got the minimum friction coefficient and wear loss, which were decreased by 72.1% and 47.6%, respectively, compared with pure Cu specimen. The friction coefficient and wear loss of W-CNTs/Cu composites were lower than those of CNTs/Cu composites, which was due to that the interracial bonding at （W-CNTs）-Cu interface was better than that at CNTs-Cu interface. The friction coefficient of composites did not vary obviously with increasing applied load, while the wear loss of composites increased significantly with the increase of applied load.

关键词： carbon nanotubes tungsten layer copper friction coefficient wear loss