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A Sequence Image Matching Method Based on Improved High-Dimensional Combined Features 被引量:2
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作者 Leng Xuefei Gong Zhe +1 位作者 Fu Runzhe Liu Yang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第5期820-828,共9页
Image matching technology is theoretically significant and practically promising in the field of autonomous navigation.Addressing shortcomings of existing image matching navigation technologies,the concept of high-dim... Image matching technology is theoretically significant and practically promising in the field of autonomous navigation.Addressing shortcomings of existing image matching navigation technologies,the concept of high-dimensional combined feature is presented based on sequence image matching navigation.To balance between the distribution of high-dimensional combined features and the shortcomings of the only use of geometric relations,we propose a method based on Delaunay triangulation to improve the feature,and add the regional characteristics of the features together with their geometric characteristics.Finally,k-nearest neighbor(KNN)algorithm is adopted to optimize searching process.Simulation results show that the matching can be realized at the rotation angle of-8°to 8°and the scale factor of 0.9 to 1.1,and when the image size is 160 pixel×160 pixel,the matching time is less than 0.5 s.Therefore,the proposed algorithm can substantially reduce computational complexity,improve the matching speed,and exhibit robustness to the rotation and scale changes. 展开更多
关键词 sequence image MATCHING navigation DELAUNAY TRIANGULATION HIGH-DIMENSIONAL combined feature k-nearest NEIGHBOR
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High Power Pulse Laser Reflection Sequence Combination with a Fast Steering Mirror 被引量:1
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作者 Ke-Ling Gong Jian Xu +9 位作者 Lin Zhang Ya-Ding Guo Bao-Shan Wang Yang Li Shuai Li Zhong-Zheng Chen Lei Yuan Yang Kou Yi-Ting Xu Qin-Jun Peng 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期52-55,共4页
We propose and demonstrate a new approach for a high power pulse laser reflection sequence combination with a fast steering mirror(FSM). This approach possesses significant advantages for lasers combining with a varie... We propose and demonstrate a new approach for a high power pulse laser reflection sequence combination with a fast steering mirror(FSM). This approach possesses significant advantages for lasers combining with a variety of output power, wavelength, pulse duration, repetition rates and polarization. The maximum number of laser routes participating in combination principally depends on the FSM’s adjustment time of the step response, lasers’ repetition rates and pulse duration. A proof-of-principle experiment is performed with two 2-kW level pulsed beams. The results indicate that the combined beam has an excellent pointing stability with rms pointing jitter^8.5μrad. Meanwhile, a high combining efficiency of 98.6% is achieved with maintaining good beam quality. 展开更多
关键词 demonstrate a new approach sequence combinATION GOOD BEAM quality
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INTEGRATED APPROACH TO ASSEMBLY SEQUENCE PLANNING OF C0MPLEX PRODUCTS 被引量:8
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作者 Wang Junfeng Liu Jihong Zhong Yifang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期181-184,共4页
Assembly sequence planning will be more difficult due to the increasingcomplexity of products.An integrated approach to assembly sequence planning of complex productsapplying de-composition-planning-combination strate... Assembly sequence planning will be more difficult due to the increasingcomplexity of products.An integrated approach to assembly sequence planning of complex productsapplying de-composition-planning-combination strategy is presented.First,an assembly is decomposedinto a hierarchical structure using an assembly structure representation based on connectors.Then,an assembly planning system is used to generate the sequences that are locally optimal for eachleaf partition hi the structure hierarchy.By combining the local sequences systematically in abottom-up manner and choosing suitable ones from the merged sequences,the assembly sequence of eachparent structure including the whole assembly is generated.An integrated system has beencompleted.A complex product is given to illustrate the feasibility and the practicality of theapproach. 展开更多
关键词 Assembly sequence planning Assembly decomposition Structure hierarchy sequence combination
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Identification of a LMNA (c.646C>T) variant by whole-exome sequencing in combination with a dilated cardiomyopathy (DCM) related gene filter in a family with familiar DCM 被引量:2
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作者 Liang Chen Zhongyin Zhou +4 位作者 Huihe Lu Ye Xie Gang Li Jianfei Huang Dongsheng Zhao 《The Journal of Biomedical Research》 CAS CSCD 2018年第4期314-316,共3页
Dilated cardiomyopathy(DCM)is characterized by the dilated heart chambers and reduced systolic function in the absence of specific aetiology[1].Approximately one third of DCM cases are hereditary.In recent years,DCM... Dilated cardiomyopathy(DCM)is characterized by the dilated heart chambers and reduced systolic function in the absence of specific aetiology[1].Approximately one third of DCM cases are hereditary.In recent years,DCM concomitant with arrhythmias and sudden death resulting from gene mutation has been widely 展开更多
关键词 related gene filter in a family with familiar DCM AVB Identification of a LMNA c.646C T variant by whole-exome sequencing in combination with a dilated cardiomyopathy
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Treatment of dehydration wastewater from licorice residue via a novel microaerobic-aerobic combined process:Performance and microbial community
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作者 Yongqi Liang Chuchu Chen +4 位作者 Yihong Chen Huazhe Wang Qi Zhao Qinglian Wu Wan-Qian Guo 《Chinese Chemical Letters》 2025年第10期499-505,共7页
The initial step in the resource utilization of Chinese medicine residues(CMRs)involves dehydration pretreatment,which results in high concentrations of organic wastewater and leads to environmental pollution.Meanwhil... The initial step in the resource utilization of Chinese medicine residues(CMRs)involves dehydration pretreatment,which results in high concentrations of organic wastewater and leads to environmental pollution.Meanwhile,to address the issue of anaerobic systems failing due to acidification under shock loading,a microaerobic expanded granular sludge bed(EGSB)and moving bed sequencing batch reactor(MBSBR)combined process was proposed in this study.Microaeration facilitated hydrolysis,improved the removal of nitrogen and phosphorus pollutants,maintained a low concentration of volatile fatty acids(VFAs),and enhanced system stability.In addition,microaeration promoted microbial richness and diversity,enriching three phyla:Bacteroidota,Synergistota and Firmicutes associated with hydrolytic acidification.Furthermore,aeration intensity in MBSBR was optimized.Elevated levels of dissolved oxygen(DO)impacted biofilm structure,suppressed denitrifying bacteria activity,led to nitrate accumulation,and hindered simultaneous nitrification and denitrification(SND).Maintaining a DO concentration of 2 mg/L enhanced the removal of nitrogen and phosphorus while conserving energy.The combined process achieved removal efficiencies of 98.25%,90.49%,and 98.55%for chemical oxygen demand(COD),total nitrogen(TN),and total phosphorus(TP),respectively.Typical pollutants liquiritin(LQ)and glycyrrhizic acid(GA)were completely degraded.This study presents an innovative approach for the treatment of high-concentration organic wastewater and provides a reliable solution for the pollution control in utilization of CMRs resources. 展开更多
关键词 combined process Pollutants removal Microaeration Expanded granular sludge bed Moving bed sequencing batch reactor Waste management
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联合抗生素对伪无菌模型大鼠的肠道菌群及其代谢的影响
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作者 贺莉 颜家朝 喻京生 《中国现代医学杂志》 2026年第3期32-43,共12页
目的比较联合抗生素经灌胃与自由饮水两种给药复制大鼠伪无菌模型的效果,为优化伪无菌模型复制方法提供参考。方法将SD大鼠随机分为正常组、抗生素灌胃组和抗生素饮水组,每组5只。抗生素灌胃组采用含200 mg/mL氨苄西林、200 mg/mL甲硝唑... 目的比较联合抗生素经灌胃与自由饮水两种给药复制大鼠伪无菌模型的效果,为优化伪无菌模型复制方法提供参考。方法将SD大鼠随机分为正常组、抗生素灌胃组和抗生素饮水组,每组5只。抗生素灌胃组采用含200 mg/mL氨苄西林、200 mg/mL甲硝唑、200 mg/mL新霉素和100 mg/mL万古霉素的混悬液,按1 mL/kg体积每日灌胃;抗生素饮水组在灭菌饮用水中加入0.5 g/L氨苄西林、0.5 g/L甲硝唑、0.5 g/L新霉素和0.25 g/L万古霉素,大鼠自由饮水,干预14 d。干预后第5、10、14天,无菌取大鼠粪便进行菌群培养;14 d后取大鼠粪便进行16S核糖体rDNA(16S rDNA)测序;分离肝脏、脾脏、肾脏、胸腺称重,取各组大鼠结肠组织进行苏木精-伊红(HE)染色及免疫组织化学染色。结果与正常组比较,在有氧和厌氧培养条件下,第5天起抗生素灌胃组和抗生素饮水组粪便菌落显著减少,伪无菌大鼠模型复制成功并稳定维持到第14天。与正常组比较,抗生素饮水组第2~6天体重均下降(P<0.05),第7~14天体重差异均无统计学意义(P>0.05);抗生素灌胃组第6天体重高于正常组(P<0.05)。正常组、抗生素灌胃组和抗生素饮水组大鼠肝脏、肾脏、脾脏和胸腺系数的比较,差异均无统计学意义(P>0.05)。各组大鼠结肠免疫组织化学结果显示,与正常组比较,抗生素灌胃组与抗生素饮水组中紧密连接蛋白闭锁小带蛋白-1(ZO-1)、闭合蛋白(Occludin)在肠上皮和腺上皮细胞细胞质及细胞膜呈阳性表达,棕黄色染色较多。基于16S rDNA测序的α多样性分析显示:与正常组比较,抗生素灌胃组和抗生素饮水组的ACE、Sobs及Shannon指数均降低(P<0.05),Simpson指数均升高(P<0.05);抗生素饮水组的Simpson指数较抗生素灌胃组升高(P<0.05)。基于Bray-Curtis距离的β多样性分析显示:正常组样本与抗生素灌胃组、抗生素饮水组样本明显分离(ANOSIM相似性分析:r=0.816,P=0.001)。抗生素灌胃组和抗生素饮水组变形菌门丰度均高于正常组(均P<0.05),抗生素灌胃组与抗生素饮水组比较,差异无统计学意义(P>0.05);正常组厚壁菌门、拟杆菌门及放线菌门丰度高于抗生素灌胃组和抗生素饮水组(均P<0.05)。抗生素饮水组摩根菌属丰度高于抗生素灌胃组和正常组(均P<0.05);抗生素灌胃组埃希-志贺菌属丰度高于抗生素饮水组和正常组(P<0.05);正常组乳酸杆菌属、拟杆菌属及norank_f__Muribaculaceae属丰度高于抗生素灌胃组和抗生素饮水组(均P<0.05)。基于KEGG的菌群功能预测分析结果显示:在碳水化合物代谢、氨基酸代谢、能量代谢、萜类化合物和聚酮类化合物代谢、辅助因子和维生素代谢等多个途径上,3组预测丰度的总体比较,差异均有统计学意义(P<0.05)。结论联合抗生素经灌胃和自由饮水给药均可在14 d内有效复制SD大鼠伪无菌模型,但抗生素灌胃组与抗生素饮水组均出现条件致病菌异常繁殖现象,这提示抗生素干预可能通过筛选压力改变菌群结构,使原本处于低丰度的潜在致病菌获得生长优势。这为研究者根据实验目标菌群选择适宜的抗生素给药策略复制伪无菌模型提供了参考。 展开更多
关键词 16s rDNA测序 伪无菌大鼠 肠道屏障 闭锁小带蛋白-1 闭合蛋白 抗生素联合使用
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宏基因二代测序在终末期肝病合并肺部感染病原学诊断的价值
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作者 方贵华 邓威 +1 位作者 陈海路 刘书娜 《胃肠病学和肝病学杂志》 2026年第1期23-29,共7页
目的探讨宏基因二代测序(metagenomics next-generation sequencing,mNGS)技术在终末期肝病(end-stage liver disease,ESLD)合并肺部感染病原学诊断中的应用价值。方法收集2022年1月至2024年8月在我院确诊为ESLD合并肺部感染患者86例的... 目的探讨宏基因二代测序(metagenomics next-generation sequencing,mNGS)技术在终末期肝病(end-stage liver disease,ESLD)合并肺部感染病原学诊断中的应用价值。方法收集2022年1月至2024年8月在我院确诊为ESLD合并肺部感染患者86例的临床资料,男59例,女27例,年龄(62.50±15.50)岁。纳入研究的86例患者中,有80例确定病原学,按照感染程度将患者分为重症组(n=42)和非重症组(n=38),并采用SPSS 23.0统计软件进行数据统计分析。结果(1)传统病原学检测结果,细菌方面共检测出8种菌属,真菌中只检测出1种菌属。(2)mNGS检测结果,细菌方面共检测出17种菌属,真菌方面共检测出3种菌属,特殊病原体方面共检测出2种菌属,病毒方面共检测出4种菌属。(3)mNGS检测的阳性率显著高于其他检测方法(P<0.05)。(4)mNGS与传统病原体培养检测、PCR检测、总体传统微生物检测相比临床诊断结果一致性较高。(5)对重症和非重症患者的临床特征进行比较,结果发现,两组患者在性别、白细胞计数、中粒细胞百分比、中粒细胞计数、血小板计数、C反应蛋白、谷丙转氨酶、谷草转氨酶、尿素氮、肌酐比较,差异均有统计学意义(P<0.05)。(6)两组患者在单纯感染和混合感染比较,差异均有统计学意义(P<0.05)。在混合感染中,细菌病毒真菌混合感染在重症患者中的比例显著高于非重症患者(P<0.05)。(7)42例重症患者在细菌属水平共检测出17种,真菌属水平检出3种,病毒检测出4种。细菌类病原菌中,假单胞菌属、克雷伯氏菌属和不动杆菌属最为常见,占比分别为42.86%、38.10%、33.33%;真菌类病原菌中,曲霉属和肺孢子菌属占比较高,占比分别为30.95%、16.67%;病毒类病原菌中,淋巴隐病毒属和玫瑰疹病毒属较为常见,占比分别为26.19%、21.43%。(8)确定病原体的80例患者,增加抗生素种类的患者为21例(48.83%)、更换抗生素种类6例(13.95%)、抗生素选用未做调整16例(37.21%)。临床结局中,重症组好转14例,病情恶化(死亡及因病危自动出院)12例,非重症组好转出院15例,病情恶化2例。结论mNGS方法检测所需时间较少、阳性率较高,且在ESLD合并感染病原学诊断中具有较高的敏感性和准确性,展现出重要的临床应用价值。 展开更多
关键词 宏基因二代测序 终末期肝病 合并肺部感染 价值
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基于G1-EWM-云模型的煤化工企业火灾风险评估
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作者 段艺蓉 杨思华 +2 位作者 李嘉雪 伊庆宇 徐佳乐 《化工自动化及仪表》 2026年第2期279-289,共11页
针对煤化工企业火灾风险评估过程中指标模糊与随机的问题,提出一种基于G1-EWM-云模型的火灾风险评估方法。以煤化工企业火灾风险等级为评价目标,从建筑防火、消防设施、工艺防火、消防安全管理和灭火救援能力5个方面构建包含32项二级指... 针对煤化工企业火灾风险评估过程中指标模糊与随机的问题,提出一种基于G1-EWM-云模型的火灾风险评估方法。以煤化工企业火灾风险等级为评价目标,从建筑防火、消防设施、工艺防火、消防安全管理和灭火救援能力5个方面构建包含32项二级指标的评价体系;采用序关系分析法(G1)确定评估指标的综合主观权重,采用熵权法(EWM)确定各指标的客观权重,通过博弈论的组合赋权法确定指标最优组合权重;将风险等级划分为安全、较安全、较危险和危险4个等级,引入云模型理论综合分析某煤化工企业的火灾风险。对某煤化工企业的评估结果表明:综合评价云数字特征值为(6.703,0.350,0.11),为较安全等级,与实际情况相符。证实G1-EWM-云模型能够全面考虑评估过程权重分配的片面性和风险状态模糊的难题,评估结果准确。 展开更多
关键词 火灾风险评估 煤化工 序关系分析法 熵权法 云模型 组合权重
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Whole-genome sequencing of monozygotic twins discordant for schizophrenia indicates multiple genetic risk factors for schizophrenia 被引量:6
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作者 Jinsong Tang Yu Fan +15 位作者 Hong Li Qun Xiang Deng-Feng Zhang Zongchang Li Ying He Yanhui Liao Ya Wang Fan He Fengyu Zhang Yin Yao Shugart Chunyu Liu Yanqing Tang Raymond C.K.Chan Chuan-Yue Wang Yong-Gang Yao Xiaogang Chen 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2017年第6期295-306,共12页
Schizophrenia is a common disorder with a high heritability, but its genetic architecture is still elusive.We implemented whole-genome sequencing(WGS) analysis of 8 families with monozygotic(MZ) twin pairs discordant ... Schizophrenia is a common disorder with a high heritability, but its genetic architecture is still elusive.We implemented whole-genome sequencing(WGS) analysis of 8 families with monozygotic(MZ) twin pairs discordant for schizophrenia to assess potential association of de novo mutations(DNMs) or inherited variants with susceptibility to schizophrenia. Eight non-synonymous DNMs(including one splicing site) were identified and shared by twins, which were either located in previously reported schizophrenia risk genes(p.V24689 I mutation in TTN, p.S2506 T mutation in GCN1L1, IVS3+1G > T in DOCK1) or had a benign to damaging effect according to in silico prediction analysis. By searching the inherited rare damaging or loss-of-function(LOF) variants and common susceptible alleles from three classes of schizophrenia candidate genes, we were able to distill genetic alterations in several schizophrenia risk genes, including GAD1, PLXNA2, RELN and FEZ1. Four inherited copy number variations(CNVs; including a large deletion at 16p13.11) implicated for schizophrenia were identified in four families, respectively. Most of families carried both missense DNMs and inherited risk variants, which might suggest that DNMs, inherited rare damaging variants and common risk alleles together conferred to schizophrenia susceptibility. Our results support that schizophrenia is caused by a combination of multiple genetic factors, with each DNM/variant showing a relatively small effect size. 展开更多
关键词 Whole-genome sequencing SCHIZOPHRENIA Monozygotic twin De novo mutation combined effect SUSCEPTIBILITY
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Differentiation degree combination weighting method for investment decision-making risk assessment in power grid construction projects 被引量:6
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作者 Yuan Chang Chenmiao Liu +4 位作者 Minghua Liu Wenxia Liu Zongqi Liu Heng Zhang Yan Zheng 《Global Energy Interconnection》 2019年第5期466-478,共13页
Power grid construction projects are distinguished by their wide variety,high investment,long payback period,and close relation to national development and human welfare.To improve the investment accuracy in such proj... Power grid construction projects are distinguished by their wide variety,high investment,long payback period,and close relation to national development and human welfare.To improve the investment accuracy in such projects and effectively prevent investment risks,this paper proposes an investment optimization decision-making method for multiple power grid construction projects under a certain investment scale.Firstly,an in-depth analysis of the characteristics and development requirements of China’s power grid projects was performed.Thereafter,the time sequence and holographic method was adopted to conduct multi-dimensional,multi-perspective risk assessment of different parts of power grid projects,and a holographic risk assessment index system was developed.Moreover,an investment decision model considering the comprehensive risk based on combination weighting was developed according to the output and input of power grid construction projects.A new combination weighting optimization method that takes into account the investment willingness of enterprises was designed to improve the current weighting evaluation methods.Finally,the validity and applicability of the proposed evaluation method were verified by case examples. 展开更多
关键词 Power grid PROJECTS Risk assessment Time sequence Index system combinATION weighting
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Number Sequencing and Architecture
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作者 Nick Huo Han Huang 《Journal of Mathematics and System Science》 2018年第1期22-24,共3页
In Chinese, Mathematics is “数学”, i.e. Numbers (数) Knowledge (学). Human identifies us ourselves from the whole one of the Universe by means of numbers, and numbers are equal object status identities, and numb... In Chinese, Mathematics is “数学”, i.e. Numbers (数) Knowledge (学). Human identifies us ourselves from the whole one of the Universe by means of numbers, and numbers are equal object status identities, and numbers counting means repetition, i.e. the process or time dimension. Given a series of n numbers, a1 , a2 , … , an , n∈N, i.e. the n objects of status, and a general formula a(i) for ordering all of the number terms by i (i=1 to n) can be generated, which shows a process of counting, and from sequencing to progression, some properties are extracted. 展开更多
关键词 Natural Numbers INTEGERS Number sequence combinations.
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SHARED CONTROL METHOD FOR COMBINATION STATE CONVERSION OF ELECTRO-MECHANICAL EQUIPMENT
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作者 Wang Qiyi Yan Xiren(Northeastern University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第4期304-308,共17页
The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by ass... The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by assembly programs, an integrated control of all the ele-ments is fulfilled. The distinguishing point of the method is that the maximum control output canbe obtained with the least input information. Hence it is the optimum for the conversion of com-bination states. Finally, a thared rotary valve is designed, and it is the simplest with only onegroup of control holes. 展开更多
关键词 Shared control combination state Encoder Cyclic sequence
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中国柽柳属植物的系统发育关系和形态演化研究 被引量:2
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作者 李海文 刘香楠 杨赵平 《塔里木大学学报》 2025年第1期19-28,共10页
柽柳属(Tamarix L.)隶属石竹目柽柳科(Tamaricaceae),为我国荒漠区主要类群,我国约有18种,柽柳属植物对维持荒漠区生态系统的稳定性发挥着绝对重要的作用。因种间形态差异小,仅依赖形态学对柽柳属的分类存在很大困难,早期基于分支分类... 柽柳属(Tamarix L.)隶属石竹目柽柳科(Tamaricaceae),为我国荒漠区主要类群,我国约有18种,柽柳属植物对维持荒漠区生态系统的稳定性发挥着绝对重要的作用。因种间形态差异小,仅依赖形态学对柽柳属的分类存在很大困难,早期基于分支分类学及分子系统学研究未能很好地解决柽柳属内的支序关系。本研究选取我国柽柳属17个物种,利用多序列联合(nrITS及叶绿体ndh F-rpl32、psb A-trn H、trn Q-rps16和trn S-trn G)进行分子系统发育树推断,在此基础上选取了3个形态特征并使用Mesquite软件进行祖先性状重建分析,探讨柽柳属物种的系统发育关系和性状演化。结果表明中国柽柳属由4个分支构成:分支1为无叶柽柳支系,叶退化为鞘状抱茎;分支2为刚毛柽柳和盐地柽柳支系,幼枝被毛;分支3由白花柽柳等5个物种组成的春花组,花为4~5基数;分支4由多枝柽柳等9个物种组成,花为5基数;这4个分支与柽柳属的生物学特征基本吻合,较好地解决了该属的支序关系。 展开更多
关键词 柽柳属 多序列联合 系统发育 共衍征
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基于SEQ2SEQ与ARIMA组合预测模型的小型模块化压水堆瞬态运行预测技术
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作者 成以恒 李桐 +4 位作者 谭思超 王博 田瑞峰 何正熙 沈继红 《核动力工程》 北大核心 2025年第4期237-244,共8页
为确保海洋条件下反应堆运行的安全可靠运行,提升海洋条件下的热工运行参数长期预测准确性,本文基于IP200的海洋条件下小型模块化压水堆一维仿真模型的热工运行数据,提出序列到序列(SEQ2SEQ)与自回归差分移动平均模型(ARIMA)的组合预测... 为确保海洋条件下反应堆运行的安全可靠运行,提升海洋条件下的热工运行参数长期预测准确性,本文基于IP200的海洋条件下小型模块化压水堆一维仿真模型的热工运行数据,提出序列到序列(SEQ2SEQ)与自回归差分移动平均模型(ARIMA)的组合预测模型,首先利用ARIMA进行数据的特征提取,随后利用SEQ2SEQ预测振荡值。反应堆在海洋条件下运行时易造成系统内部液面的晃荡,进而导致其他运行参数发生波动。对稳压器压力、冷却剂流量、蒸汽发生器蒸汽出口流量三种不同振荡特征的热工运行参数的预测结果表明:较单独使用ARIMA、SEQ2SEQ模型与传统长短期记忆网络(LSTM)模型相比,预测精度提升约一个数量级。本研究提出的ARIMA和SEQ2SEQ组合预测模型具有计算速度快、预测精度高的特点,为海洋条件下小型模块化压水堆的潜在故障预测提供了一种有效方法。 展开更多
关键词 海洋条件下热工参数预测 自回归差分移动平均模型(ARIMA)与序列到序列(SEQ2SEQ)组合模型 小型模块化压水堆
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小鼠胰腺癌放疗联合免疫治疗的转录组测序分析及关键基因的筛选和验证
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作者 陈双伟 任永飞 +1 位作者 王玥 蔡华忠 《江苏大学学报(医学版)》 2025年第5期392-400,428,共10页
目的:探究胰腺癌放疗联合免疫治疗中的基因表达变化并筛选和验证其中的关键基因。方法:取20只6~8周龄C57BL/6J雄性小鼠,随机均分为4组,分别为对照组、放疗组、免疫治疗组、放疗联合免疫治疗组,每组5只,通过皮下注射胰腺癌KPC细胞构建荷... 目的:探究胰腺癌放疗联合免疫治疗中的基因表达变化并筛选和验证其中的关键基因。方法:取20只6~8周龄C57BL/6J雄性小鼠,随机均分为4组,分别为对照组、放疗组、免疫治疗组、放疗联合免疫治疗组,每组5只,通过皮下注射胰腺癌KPC细胞构建荷瘤小鼠模型,放疗组行8 Gy射线单次照射,免疫治疗组行单次腹腔注射PD-1单抗(200μg/只),放疗联合免疫治疗组行单次8 Gy射线照射后腹腔注射PD-1单抗(200μg/只),对照组无处理,7 d后取出瘤体,行转录组学测序;将表达显著的差异表达基因(differentially expressed genes, DEGs)进行GO、KEGG及Reactome功能注释分析,探索相关信号通路;将上调的DEGs行韦恩分析并取交集,结合生存分析筛选出关键基因,分析其表达情况,探究与免疫细胞浸润及免疫检查点的关系,并构建蛋白质相互作用网络分析其相互作用的基因群。构建两种胰腺癌KPC、PANC02细胞系C57BL/6J雄性小鼠皮下荷瘤模型,次日采用放疗联合免疫治疗,维持3 d;至第12天,取肿瘤组织,qRT-PCR法检测关键基因mRNA在瘤体组织中的相对表达量。结果:转录组测序分析结果显示,与放疗组、免疫治疗组相比,放疗联合免疫治疗组DEGs最为丰富,并主要参与代谢、免疫系统及信号转导方面相关的信号通路。将放疗组、免疫治疗组及放疗联合免疫组上调基因进行韦恩分析得到11个交集基因,通过生存分析,筛选出关键基因黏液病毒耐药1(myxovirus resistance 1,MX1),其在胰腺癌中高表达且与胰腺癌患者预后呈显著负相关(P<0.05)。胰腺癌中MX1 mRNA表达与中性粒细胞、树突状细胞浸润丰度呈正相关(r=0.413,0.333;P均<0.05),并与免疫检查点CD80、CD274、CD86表达呈正相关(P均<0.05)。MX1在胰腺癌中相互作用的基因群包括OASL1、RSAD2、IFIT1、IFIT2和IFIT3。qRT-PCR结果显示,在胰腺癌KPC、PANC02细胞荷瘤小鼠模型中,与对照组相比,放疗联合免疫治疗组MX1 mRNA相对表达量明显增加(P<0.05)。结论:在胰腺癌放疗联合免疫治疗中MX1 mRNA相对表达明显增加,其可能是关键基因之一。 展开更多
关键词 MX1 转录组测序 胰腺癌 放疗联合免疫治疗
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基于多维灰色组合模型的CPI预测应用研究
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作者 王旻燕 王兴龙 汪亚 《软件》 2025年第2期37-39,共3页
CPI能够反映一定时期内人们购买一组代表性商品和服务总花费的变化情况。为提高多维灰色模型对区间数序列预测的精确度,本文将两个多维区间数序列灰色模型MINGM(0,2)、MINGM(1,2)进行组合。首先,分别建立两个单一模型并根据二者自身的... CPI能够反映一定时期内人们购买一组代表性商品和服务总花费的变化情况。为提高多维灰色模型对区间数序列预测的精确度,本文将两个多维区间数序列灰色模型MINGM(0,2)、MINGM(1,2)进行组合。首先,分别建立两个单一模型并根据二者自身的拟合及预测结果确定变权系数,从而建立新的多维灰色组合模型;其次,用我国2008—2024年CPI数据作为系统特征序列,将衣着类居民消费价格指数作为相关因素序列,对组合模型的准确性进行评价。结果表明,改进后的多维灰色组合模型不论是拟合还是预测精度都得到了显著提升。 展开更多
关键词 多维灰色模型 区间数序列 变权组合预测 CPI
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基于时序运行模拟的新能源电力系统典型场景生成方法 被引量:2
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作者 彭竹弈 宋杉 +4 位作者 许偲轩 顾康慧 葛毅 王荃荃 孙文涛 《浙江电力》 2025年第5期66-75,共10页
传统基于源荷信息的聚类方法难以准确描述新能源电力系统的时序运行特征。为此,考虑电力系统交流潮流分布和机组启停策略,提出一种基于时序运行模拟的新能源电力系统典型场景生成方法。首先,构建计及交流潮流约束的机组组合模型,采用基... 传统基于源荷信息的聚类方法难以准确描述新能源电力系统的时序运行特征。为此,考虑电力系统交流潮流分布和机组启停策略,提出一种基于时序运行模拟的新能源电力系统典型场景生成方法。首先,构建计及交流潮流约束的机组组合模型,采用基于二阶锥松弛的两阶段求解策略,在多时段最优潮流模型中开展8760 h时序模拟;其次,根据时序模拟结果的新能源出力水平、线路阻塞情况、机组启停情况等数据特征,采用改进的K-means算法提取典型场景;最后,通过算例分析验证提出方法的有效性,为新能源电力系统规划和调度提供参考依据。 展开更多
关键词 全时序运行模拟 最优潮流 机组组合 二阶锥松弛 典型场景
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不同环境剖面次序对某自动步枪可靠性影响分析
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作者 李朋超 苑大威 +1 位作者 沙金龙 陈云霞 《装备环境工程》 2025年第7期44-49,共6页
目的 量化分析不同环境剖面次序对自动步枪可靠性的影响。方法 以某小口径自动步枪为试验对象,按照常温、低温、盐雾、高温、浸河水、扬尘环境剖面顺序开展试验,统计不同环境剖面时序组合下的故障数据,建立寿命周期内累计故障预测模型,... 目的 量化分析不同环境剖面次序对自动步枪可靠性的影响。方法 以某小口径自动步枪为试验对象,按照常温、低温、盐雾、高温、浸河水、扬尘环境剖面顺序开展试验,统计不同环境剖面时序组合下的故障数据,建立寿命周期内累计故障预测模型,分析获得不同环境剖面次序对自动步枪可靠性的影响显著度。结果 不同环境剖面时序组合下,自动步枪的故障数差别较大,不同环境剖面的次序对自动步枪可靠性的影响程度不同。结论 扬尘对后续剖面的次序效应最为显著,常温次序效应最不显著,高温和低温两剖面易受其余剖面的影响。 展开更多
关键词 环境剖面 剖面时序组合 剖面次序 次序效应 自动步枪 可靠性影响
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Some Statistical Properties of the Correlation Function of Combination Sequences
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作者 Yu Kai Lu Chuanlai(Department of information Engineering. Beijing University of Posts and Telecommunications,Beijing, 100088,P.R.China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 1996年第1期53-58,共6页
in this paper,the statistical prOPerties of random combination sequences are discussed.Thevalue of E{R(r)}and the upper bound of E{A(r)}are derived.In the end,a new method to find a longsequence with low autocorrelati... in this paper,the statistical prOPerties of random combination sequences are discussed.Thevalue of E{R(r)}and the upper bound of E{A(r)}are derived.In the end,a new method to find a longsequence with low autocorrelation value is given. 展开更多
关键词 s:correlation function combination sequence mathematical expectation
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基于混合熵与组合预测模型的机车轴承故障诊断
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作者 赵庆国 杨江天 《机车电传动》 2025年第5期121-127,共7页
机车轴承剩余使用寿命(remaining useful life,RUL)预测对减少机车的计划外维修、提高机车可靠性和安全性具有重要意义。RUL预测的准确程度取决于所采用的诊断指标和预测模型。文章提出采用复合多尺度模糊熵和复合多尺度分散熵构造混合... 机车轴承剩余使用寿命(remaining useful life,RUL)预测对减少机车的计划外维修、提高机车可靠性和安全性具有重要意义。RUL预测的准确程度取决于所采用的诊断指标和预测模型。文章提出采用复合多尺度模糊熵和复合多尺度分散熵构造混合熵,从随机性和模糊性两个不同的角度对信号的不确定性进行统一描述,其性能优于传统的诊断指标,并在此基础上,进一步提出基于小波变换、差分自回归移动平均(autoregressive integrated moving average,ARIMA)模型和改进GM(1,1)模型混合预测方法。定期采集轴承振动信号,计算混合熵值,构成一个时间序列,用小波变换将混合熵序列分解为不同的小波系数,然后分别应用递减序列GM(1,1)模型和ARIMA模型预测呈现出递减趋势的小波系数和随机趋势的小波系数。通过小波重构得到总的预测结果。试验结果表明,文章提出的方法能准确预测机车轴承剩余使用寿命。 展开更多
关键词 机车寿命 剩余使用寿命 混合熵 组合预测模型 递减序列GM(1 1)模型 故障诊断 轴承
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