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Tsinghua Science and Technology 2021年第4期26卷 464-474页

作者： Jian Guo Hong Liang Songpu Ai chao lu Haochen Hua Junwei Cao Beijing National Research Center for Information Science and Technology Beijing 100084China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China

Electrical power network analysis and computation play an important role in the planning and operation of the power grid,and they are modeled mathematically as differential equations and network algebraic *** direct method based on Gaussian elimination theory can obtain analytical *** factors affect computing efficiency:the number of nonzero element fillings and the length of elimination *** article constructs mapping correspondence between eliminated tree nodes and quotient graph nodes through graph and quotient graph *** Approximate Minimum Degree(AMD)of quotient graph nodes and the length of the elimination tree nodes are composed to build an Approximate Minimum Degree and Minimum Length(AMDML)*** quotient graph node with the minimum degree,which is also the minimum length of elimination tree node,is selected as the next ordering *** with AMD ordering method and other common methods,the proposed method further reduces the length of elimination tree without increasing the number of nonzero fillings;the length was decreased by about 10%compared with the AMD method.A testbed for experiment was *** efficiency of the proposed method was evaluated based on different sizes of coefficient matrices of power flow cases.

关键词： Approximate Minimum Degree and Minimum Length(AMDML) electrical power network analysis elimination tree numerical solution ordering method

Microstructure and Properties of Mo Microalloyed Cold Rolled DP1000 Steels

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Journal of Iron and Steel Research International 2011年第5期18卷 52-58页

作者： HAN Qi-hang KANG Yong-lin ZHAO Xian-meng lu chao GAO lu-feng School of Materials Science and Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China

Two kinds of ultra-high strength cold rolled dual phase steels have been developed by designing C-Si-Mn-Cr and C-Si-Mn-Cr-Mo alloy systems. Tensile strength and elongation of both steels exceed 1100 MPa and 10%,respectively. The microstructures of both steels consist of massive martensite and ferrite. And the massive martensite of Mo-free steel disperses in the ferrite with volume fraction of 64%. However,the massive martensite of Mo-containing steel is connected or closed by small martensite islands each other,and martensite volume fraction is 69%. As to Mo-free steel,the yield strength,yield ratio,and work hardening exponent n are 548 MPa,0.49,and 0.26,respectively. As for Mo-containing one,the yield strength,yield ratio,and n value are 746 MPa,0.66,and 0.33,respectively. Besides,the ferrite of Mo-free steel is deformed at the initial stage of plastic deformation. However,for Mo-containing one,Mo solution strengthened ferrite and small overaged martensite islands are deformed preferentially at small strain,which causes the yield strength to reach approximately 200 MPa higher than that of Mo-free steel.

关键词： Mo dual phase steel microstructure property deformation mechanism

High-elevation landforms are experiencing more remarkable wetting trends in arid Central Asia

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Advances in Climate Change Research 2022年第4期13卷 489-495页

作者： Yong ZHANG Cheng-Bang AN lu-Yu LIU Yan-Zhen ZHANG chao lu Wen-Sheng ZHANG Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

Since the 1980s,a warming and weting trend in arid Central Asia(ACA)has been widely ***,no consistent knowledge has been presented about whether warming and weting trends are evenly distributed throughout ACA or whether there are noticeable topographical *** combined the ERA5-Land reanalysis dataset and data from Google Earth Engine to analyze the topographic differences of ACA from 1981 to *** findings indicate that significant(p<0.05)warming has a broader geographic scale in ACA and that warming rate of low-elevation landforms(high plains and hlls)is higher than that of high-elevation landforms(mountains and tablelands).However,the weting trend does not fllow this *** contrast,high-elevation landforms have a higher wetting rate than low-elevation landforms and are the main areas of ***,low-elevation landforms continue to maintain the warming and drying ***,the wetting trend of high-elevation landforms is amplified with ***,the wetting trend is negatively related to the warming trend(p<0.01)across the entire elevation ***,the findings provide new insights into the current research hotspot of warming-wetting"trend in ACA and highlight the differences in the responses of different landforms to climate change.

关键词： Arid Central Asia Warming and wetting Topographical differences ERA5 Google Earth Engine

变速器主壳体高压铸造工艺中压射高低速切换点优化

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特种铸造及有色合金 2024年第1期44卷 130-134页

作者：范寅生李亨鲁超李明赵永征吴玉程合肥工业大学材料科学与工程学院合肥230009 合肥亚明汽车部件有限公司合肥231131 合肥江淮铸造有限责任公司合肥231131

对9AT汽车变速箱主壳体的压铸成形过程进行充型仿真,分析了不同压射高低速切换点对金属液流动和充型的影响。结果表明,当压射低速值为0.2 m/s,高速值为3.5 m/s,高低速切换点为560 mm时,模流平稳,卷气概率最低。采用该工艺参数进行试生产... 详细信息

对9AT汽车变速箱主壳体的压铸成形过程进行充型仿真,分析了不同压射高低速切换点对金属液流动和充型的影响。结果表明,当压射低速值为0.2 m/s,高速值为3.5 m/s,高低速切换点为560 mm时,模流平稳,卷气概率最低。采用该工艺参数进行试生产,铸件组织致密,力学性能较好。

关键词：压铸变速器壳体模拟力学性能

免疫细胞及炎症因子对晚期肺癌一线化疗效果的预测价值

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医学临床研究 2024年第5期41卷 750-753页

作者：卢超胡志清吴亚斌洛阳市中心医院检验科河南洛阳471000

【目的】探讨T淋巴细胞亚群、肿瘤浸润T淋巴细胞(Tils)及炎症因子对晚期肺癌一线化疗效果的预测价值。【方法】检测98例首诊TNM分期为Ⅲ/Ⅳ期的非小细胞肺腺癌患者的血清白细胞介素1α(IL-1α)、IL-6、IL-17、γ-干扰素(INF-γ)水平及T... 详细信息

【目的】探讨T淋巴细胞亚群、肿瘤浸润T淋巴细胞(Tils)及炎症因子对晚期肺癌一线化疗效果的预测价值。【方法】检测98例首诊TNM分期为Ⅲ/Ⅳ期的非小细胞肺腺癌患者的血清白细胞介素1α(IL-1α)、IL-6、IL-17、γ-干扰素(INF-γ)水平及T淋巴细胞亚群CD4^(+)T、CD8^(+)T、调节性T细胞、CD57^(+)细胞、Granzyme B^(+)细胞、CD45RO^(+)细胞比例;所有患者均接受紫杉醇注射液+顺铂化疗,治疗4个周期后评定疗效,并据此分为有效组和无效组,分析化疗无效的影响因素及预测疗效的有效标志物。【结果】化疗后,98例患者中69例化疗有效,29例无效。无效组患者淋巴结转移占比及调节性T细胞、IL-1α表达水平均高于有效组(P<0.05),CD57^(+)细胞、CD45RO^(+)细胞比例均低于有效组(P<0.05)。多因素逐步Logistic回归分析结果显示,调节性T细胞、IL-1α水平高是肺癌患者化疗无效的危险因素(P<0.05),CD57^(+)细胞、CD45RO^(+)细胞比例高是保护因素(P<0.05)。受试者工作特征(ROC)曲线分析显示,调节性T细胞、CD57^(+)细胞、CD45RO^(+)细胞、IL-1α水平预测化疗效果的灵敏度分别为82.76%、86.21%、89.66%、93.10%,四者联合的灵敏度、特异度和曲线下面积(AUC)分别为82.76%、97.10%、0.957。【结论】T淋巴细胞亚群、Tils及炎症因子水平与晚期肺癌治疗效果密切相关,其可作为预测疗效的敏感指标。

关键词：肺肿瘤 T淋巴细胞亚群炎症趋化因子类/血液药物疗法治疗结果

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胰腺巨大脂肪瘤一例

肝胆胰外科杂志 2024年第1期36卷 48-49页

作者：陈波杨倩卢超胡继明王帅长江大学附属荆州医院肝胆胰脾外科湖北荆州434000 长江大学附属荆州医院超声科湖北荆州434000

胰腺脂肪瘤起源于胰腺间叶组织,是由胰腺脂肪细胞异常克隆所致的一种少见的良性肿瘤,而胰腺巨大脂肪瘤则更罕见。本文回顾性分析长江大学附属荆州医院1例胰腺巨大脂肪瘤的诊治经过和体会,现报道如下。病例患者男性,50岁,因“进食后上腹... 详细信息

胰腺脂肪瘤起源于胰腺间叶组织,是由胰腺脂肪细胞异常克隆所致的一种少见的良性肿瘤,而胰腺巨大脂肪瘤则更罕见。本文回顾性分析长江大学附属荆州医院1例胰腺巨大脂肪瘤的诊治经过和体会,现报道如下。病例患者男性,50岁,因“进食后上腹部饱胀不适半年”于2022年3月20日入院,7年前因胆囊结石行腹腔镜胆囊切除术,查体无殊。实验室检查:血常规、肝肾功能、肿瘤标志物等各项指标均正常。

关键词：胰腺脂肪瘤巨大诊断治疗

基于蝙蝠—粒子群算法优化BP神经网络的电动汽车锂电池故障诊断

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苏州市职业大学学报 2024年第3期35卷 45-51页

作者：乔维德陆超袁桂芳无锡开放大学科研与发展规划处江苏无锡214011 无锡开放大学教务处江苏无锡214011 江苏联合职业技术学院无锡机电分院自动化工程系江苏无锡214028

针对电动汽车锂电池故障诊断问题,在分析锂电池故障特征与故障原因的基础上,建立电动汽车锂电池故障诊断模型。该模型包括锂电池故障样本采集处理、BP神经网络、故障特征编码输出及故障类型诊断。采取蝙蝠—粒子群算法优化BP神经网络初... 详细信息

针对电动汽车锂电池故障诊断问题,在分析锂电池故障特征与故障原因的基础上,建立电动汽车锂电池故障诊断模型。该模型包括锂电池故障样本采集处理、BP神经网络、故障特征编码输出及故障类型诊断。采取蝙蝠—粒子群算法优化BP神经网络初始结构参数,利用改进BP算法和故障样本训练并测试BP神经网络。仿真实验结果表明:相比BP算法、遗传算法、粒子群算法,蝙蝠—粒子群算法优化BP神经网络的故障诊断准确性最高、训练时间最短、训练误差最小。

关键词：锂电池 BP神经网络蝙蝠—粒子群算法故障诊断

地铁分时定价措施对不同类型乘客出行选择行为影响研究

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现代城市轨道交通 2024年第2期 112-117页

作者：马铭遥路超吴一迪珠海市规划设计研究院广东珠海519075

地铁高峰期拥挤是亟需解决的重要民生问题,地铁分时定价措施是有效缓解高峰期拥挤的需求管理措施之一。文章对不同地铁分时定价措施下的乘客出行选择行为进行研究,有助于制定合理的地铁分时定价措施,有效缓解高峰期拥挤现象。首先,采取... 详细信息

地铁高峰期拥挤是亟需解决的重要民生问题,地铁分时定价措施是有效缓解高峰期拥挤的需求管理措施之一。文章对不同地铁分时定价措施下的乘客出行选择行为进行研究,有助于制定合理的地铁分时定价措施,有效缓解高峰期拥挤现象。首先,采取意向(SP)与行为(RP)问卷调查获取基础数据;然后,采用二阶聚类法将乘客划分为3类,并分析乘客类别特征;最后,采用多元Logistics回归模型深入分析各类乘客的出行特征,重点分析不同分时定价措施下乘客的出行选择行为,由分析结果可知类型2和类型3乘客对于分时定价措施敏感,选择转移至平峰期或其他交通方式出行。

关键词：地铁分时定价措施乘客出行选择行为聚类分析回归分析

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Assembling aggregation-induced emission with natural DNA to maximize donor/acceptor ratio for efficient light-harvesting antennae

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聚集体(英文)

聚集体(英文) 2023年第4期4卷 239-245页

作者： Xiaofang Tang Yaping Zhu Weijiang Guan chao lu Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouChina State Key Laboratory of Chemical Resource Engineering and College of ChemistryBeijing University of Chemical TechnologyBeijingChina

Arranging dense donors around a single acceptor for the assembly of effi-cient light-harvesting antennas is a long-standing challenge due to the intractable aggregation-caused quenching of dense ***,we designed a cationic aggregation-induced emission(AIE)amphiphile to self-assemble with natural DNA *** an efficient donor,the as-prepared cationic AIE amphiphile could be densely attached to the phosphate groups of natural DNA duplexes by using the smaller cationic *** long alkyl chain between the cationic trimethylammonium and the AIEfluorophore allowed for avoiding the insuffi-cient binding caused by the steric hindrance of the AIEfluorophore,resulting in a remarkably high donor/acceptor ratio comparable to that of the widely developed custom DNA *** proposed self-assembly strategy provided novelflex-ible avenues for the assembling offinely controlled and efficient light-harvesting systems into natural DNA with little synthetic modifications and low cost.

关键词： aggregation-induced emission DNA energy transfer light-harvesting supramolecular assembly

2021—2023年麻城市某医院降糖药使用情况分析

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中国社区医师 2024年第16期40卷 7-9页

作者：熊芸万兰心吴谨卢超麻城市人民医院药剂科湖北麻城438300

目的:分析2021—2023年麻城市某医院降糖药使用情况,为促进临床合理用药提供依据。方法:收集2021—2023年麻城市人民医院降糖药使用情况,包括降糖药物品种、销售金额、用药频度(DDDs)。结果:2021—2023年,麻城市人民医院口服降糖药销售... 详细信息

目的:分析2021—2023年麻城市某医院降糖药使用情况,为促进临床合理用药提供依据。方法:收集2021—2023年麻城市人民医院降糖药使用情况,包括降糖药物品种、销售金额、用药频度(DDDs)。结果:2021—2023年,麻城市人民医院口服降糖药销售金额呈下降趋势,胰岛素销售金额逐年上升,由于该院引进较多带量采购品种,胰岛素销售金额占比上并无较大增长。2021—2023年,口服降糖药销售金额前三位是α糖苷酶抑制药、双胍类、钠-葡萄糖协同转运蛋白2(SGLT-2)抑制剂,(1)α糖苷酶抑制药(共3个品种,阿卡波糖、伏格列波糖、米格列醇),3年平均销售额为861990.47元;(2)双胍类(二甲双胍),3年平均销售额为486325.47元;(3)SGLT-2抑制剂(共2个品种,达格列净、恩格列净),3年平均销售额为275695.81元。2021—2023年口服降糖药DDDs值前三位是格列美脲、二甲双胍、阿卡波糖,其中二甲双胍、阿卡波糖DDDs值逐年上升,格列美脲逐年下降。结论:2021—2023年,胰岛素是麻城市人民医院降糖主流药物,用药金额前3位的是α糖苷酶抑制药、双胍类、SGLT-2抑制剂,DDDs排序前3位是格列美脲、二甲双胍、阿卡波糖,临床用药结构基本合理。

关键词：糖尿病用药频度降糖药