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Forecasting Method of Stock Market Volatility in Time Series Data Based on Mixed Model of ARIMA and XGBoost

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China Communications 2020年第3期17卷 205-221页

作者： Yan Wang yuankai Guo College of Computer and Communication LanZhou University of TechnologyLanzhou 730050China

Stock price forecasting is an important issue and interesting topic in financial *** reasonable and accurate forecasts have the potential to generate high economic benefits,many researchers have been involved in the study of stock price *** this paper,the DWT-ARIMAGSXGB hybrid model is ***,the discrete wavelet transform is used to split the data set into approximation and error *** the ARIMA(0,1,1),ARIMA(1,1,0),ARIMA(2,1,1)and ARIMA(3,1,0)models respectively process approximate partial data and the improved xgboost model(GSXGB)handles error partial ***,the prediction results are combined using wavelet *** to the experimental comparison of 10 stock data sets,it is found that the errors of DWT-ARIMA-GSXGB model are less than the four prediction models of ARIMA,XGBoost,GSXGB and *** simulation results show that the DWT-ARIMA-GSXGB stock price prediction model has good approximation ability and generalization ability,and can fit the stock index opening price *** the proposed model is considered to greatly improve the predictive performance of a single ARIMA model or a single XGBoost model in predicting stock prices.

关键词： hybrid model discrete wavelet transform ARIMA XGBoost,grid search stock price forecast

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胡杨叶功能性状与土壤因子的关系

生态学报 2024年第4期44卷 1717-1726页

作者：冯宇王雨晴李沅楷韩路王海珍塔里木大学生命科学与技术学院阿拉尔843300 塔里木大学农学院阿拉尔843300 塔里木大学园艺与林学学院阿拉尔843300

探究荒漠植物叶功能性状对土壤环境因子的响应格局,对理解干旱荒漠区优势植物适应干旱贫瘠逆境的权衡策略至关重要。以塔里木河干流上游胡杨为研究对象,研究不同生境胡杨叶功能性状变异格局及其与土壤因子的相互关系,以揭示胡杨适应干... 详细信息

探究荒漠植物叶功能性状对土壤环境因子的响应格局,对理解干旱荒漠区优势植物适应干旱贫瘠逆境的权衡策略至关重要。以塔里木河干流上游胡杨为研究对象,研究不同生境胡杨叶功能性状变异格局及其与土壤因子的相互关系,以揭示胡杨适应干旱荒漠环境的生态策略。结果表明:(1)胡杨叶功能性状在不同地下水埋深(GWD, groundwater depth)之间差异显著(P<0.05),比叶面积(SLA, specific leaf area)、叶宽(LW, leaf width)、叶面积(LA, leaf area)随GWD增加而显著下降(P<0.05),叶长(LL, leaf length)、叶干物质含量(LDMC, leaf dry mass)、叶组织密度(LTD, leaf tissue density)则显著增大(P<0.05);其中LW、LA变异系数较高(48.6%、39.4%),对GWD变化较敏感。(2)浅GWD生境土壤有机碳(SOC, soil organic carbon)、全氮(TN, total nitrogen)、全磷含量(TP, total phosphorus)与氮磷比(N/P, nitrogen phosphorus ratio)显著高于深GWD生境(P<0.05),碳氮比(C/N, carbon nitrogen ratio)则相反;其中TN、SOC、N/P变异系数较高(≥40.0%),对GWD变化较敏感。(3)冗余分析表明,C/N、N/P、TN、SOC是影响胡杨叶功能性状的主要因子,其中C/N显著影响LW、LA与SLA,N/P则显著影响LL与LDMC,TN显著影响LTD(P<0.05)。(4)随GWD增加,土壤库养分减少,林下土壤旱化贫瘠。胡杨为了生存,通过减小LW、LA、SLA,增加LL、LTD、LDMC来适应日益干旱贫瘠的荒漠环境。

关键词：胡杨叶功能性状土壤因子地下水埋深适应策略

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从青蒿素重结晶废料中回收青蒿素的方法

化工技术与开发 2020年第11期49卷 1-3页

作者：周源凯万凌云韦树根潘丽梅付金娥广西仙草堂制药有限责任公司广西柳州545400 广西壮族自治药用植物园广西南宁530023

本文探索从青蒿素重结晶后的废料中回收青蒿素的工艺。采用萃取-两相溶剂结晶法,从废料中回收青蒿素,回收率可达76.5%,纯度为85%。从重结晶废料中回收青蒿素,方法简单,易操作,成本低,回收率高,可提高企业的整体经济效益。

关键词：青蒿素重结晶废料两相萃取结晶

Efficacy and safety of anlotinib plus penpulimab as second-line treatment for small cell lung cancer:A multicenter,open-label,single-arm phase II trial

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Cancer Pathogenesis and Therapy 2024年第4期2卷 268-275页

作者： Changgong Zhang Jianhua Chen Huijuan Wu Jun Wang Liying Gao Jun Zhao Yan Sun Zhongyao Jia Xinlin Mu Chunmei Bai Rui Wang Kailiang Wu Qiang Liu yuankai Shi Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing Key Laboratory of Clinical Study on Anticancer Molecular Targeted DrugsBeijing 100021China Department I of Thoracic Oncology Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South UniversityChangshaHunan 410083China Department of Oncology The Affiliated Cancer Hospital of Zhengzhou UniversityZhengzhouHenan 450000China Department II of Head and Neck Tumor Gansu Provincial Cancer HospitalLanzhouGansu 730050China Department III of Radiotherapy Gansu Provincial Cancer HospitalLanzhouGansu 730050China Department I of Thoracic Oncology Beijing Cancer HospitalBeijing 100142China Department of Oncology Linyi People's HospitalLinyiShandong 276002China Department of Respiratory and Critical Care Medicine Peking University People's HospitalBeijing 100032China Department of Medical Oncology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Thoracic Surgery The Fourth Hospital of Hebei Medical UniversityShijiazhuangHebei 050000China Department of Radiation Oncology Shanghai Proton and Heavy Ion CenterFudan University Cancer HospitalShanghai 200030China Department I of Oncology Shenyang Chest HospitalShenyangLiaoning 110044China

Background:Currently,the need for new therapeutic strategies involving programmed cell death protein-1(PD-1)monoclonal antibodies in the second-line setting of small cell lung cancer(SCLC)is *** study aimed to evaluate the efficacy and safety of anlotinib plus penpulimab as a second-line treatment for patients with SCLC who progressed after first-line platinum-based ***:This study included the patients from Cohort 4 of a single-arm,open-label,multicenter,phase II clinical trial.A safety run-in phase was performed under anlotinib(10/12 mg quaque die[QD],days 1–14)plus penpulimab(200 mg intravenously[IV],day 1)in a 21-day cycle,followed by the formal trial in which the patients received anlotinib(12 mg QD,days 1–14)plus penpulimab(200 mg IV,day 1)in a 21-day *** primary endpoint of the safety run-in phase was *** primary endpoint of the formal trial phase was the objective response rate(ORR).Results:From April 28,2020,to November 24,2020,21 patients were enrolled from 11 hospitals,including 2 in the safety run-in phase and 19 in the formal trial *** the formal trial phase,the ORR was 42.1%(8/19;95%confidence interval[CI]:17.7–66.6%).The median progression-free survival was 4.8 months(95%CI:2.9–11.3 months),and the median overall survival was 13.0 months(95%CI:4.6–not applicable[NA]months).The incidence of grade 3 treatment-related adverse events(TRAEs)was 52.4%(11/21),and the incidence of treatment-related serious adverse events(AEs)was 28.6%(6/21).Two AE-related deaths *** most common AEs were hypertension(57.1%,12/21),hypothyroidism(42.9%,9/21),and hypertriglyceridemia(38.1%,8/21).Conclusions:In patients with SCLC who progressed after first-line platinum-based chemotherapy,the second-line anlotinib plus penpulimab treatment demonstrates promising anti-cancer activity and a manageable safety profile,which warrants further investigation.

关键词： Anlotinib Penpulimab Small cell lung cancer Efficacy Safety Phase II trial

多索茶碱通过激活AMPK通路改善过氧化氢诱导的PC12细胞氧化损伤

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中国现代应用药学 2024年第15期41卷 2051-2057页

作者：钟丽丽秦元锴刘玫凌佳楠赵霞杭州医学院药学院杭州311399

目的研究多索茶碱对过氧化氢(H2O2)诱导的PC12细胞毒性的保护作用及其潜在机制。方法采用H2O2建立细胞氧化损伤模型。MTT检测细胞活力;Tunel染色、流式细胞仪、Caspase-3活性试剂盒检测细胞凋亡;乳酸脱氢酶试剂盒检测细胞膜损伤;JC-1染... 详细信息

目的研究多索茶碱对过氧化氢(H2O2)诱导的PC12细胞毒性的保护作用及其潜在机制。方法采用H2O2建立细胞氧化损伤模型。MTT检测细胞活力;Tunel染色、流式细胞仪、Caspase-3活性试剂盒检测细胞凋亡;乳酸脱氢酶试剂盒检测细胞膜损伤;JC-1染色检测线粒体膜电位和DCFH-DA试剂检测细胞内ROS的产生;Western blotting用于检测信号通路蛋白水平的变化。结果多索茶碱浓度依赖性改善了H2O2诱导的PC12细胞内ROS的异常水平,恢复了线粒体膜电位,降低了Caspase-3激活,进而降低了PC12细胞凋亡。多索茶碱刺激PC12细胞中AMPK的磷酸化,抑制AMPK信号通路其保护作用可被逆转。结论多索茶碱通过激活AMPK信号通路改善H2O2诱导的PC12细胞损伤。

关键词：多索茶碱过氧化氢 PC12细胞氧化应激 AMPK信号通路

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某船舶餐厅振动噪声分析及治理

噪声与振动控制 2024年第3期44卷 177-182,208页

作者：高处詹蓉苏元凯高晓磊司南中国船舶及海洋工程设计研究院上海200011 三沙市船务管理局海南三沙570102

某船舶大餐厅与机舱公用部分钢围壁导致餐厅噪声水平超标,严重影响船员就餐舒适性。基于统计能量分析法和经验分析法,对餐厅所在舱段进行声学仿真,通过对比数值计算结果与实测数据,分析餐厅噪声来源及组成,确定在外部控制振源,在内部敷... 详细信息

某船舶大餐厅与机舱公用部分钢围壁导致餐厅噪声水平超标,严重影响船员就餐舒适性。基于统计能量分析法和经验分析法,对餐厅所在舱段进行声学仿真,通过对比数值计算结果与实测数据,分析餐厅噪声来源及组成,确定在外部控制振源,在内部敷设浮筑地板、吸隔声材料的综合治理方案,最终有效控制餐厅噪声。从工程实践角度为毗邻主要声源的船舶舱室噪声治理提供一种参考方法,并提出一些建议。

关键词：振动与波统计能量分析船上餐厅声能量降噪设计

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面向空调管路布置的空间向量搜索算法

合肥工业大学学报（自然科学版） 2024年第2期47卷 176-181页

作者：唐景春刘逸卢剑伟任远凯黄克合肥工业大学汽车与交通工程学院安徽合肥230009 合肥工业大学机械工程学院安徽合肥230009

针对构型要求复杂且经验类规则难以量化的空调压缩机管路布置问题,文章提出一种基于逃逸法的向量搜索管路布置算法。该算法分为预处理和搜索2个过程。在预处理过程中,使用三维网格记录管路布置空间信息,根据管路直径确定网格大小。对于... 详细信息

针对构型要求复杂且经验类规则难以量化的空调压缩机管路布置问题,文章提出一种基于逃逸法的向量搜索管路布置算法。该算法分为预处理和搜索2个过程。在预处理过程中,使用三维网格记录管路布置空间信息,根据管路直径确定网格大小。对于有无构型要求的2种管路,采用不同形状的单元格来划分网格,保证单元格精度满足要求,减少算法运算量。在搜索过程中,有构型要求管路采用竖直向量圆周搜索,无构型要求管路采用竖直水平向量交替搜索,确保走管路径符合空调管路布置规范要求。通过算例分析验证了该算法的有效性,可为突破复杂约束条件下空调器管路自动布管技术提供算法支撑。

关键词：空调管路构型约束空间向量搜索逃逸法

A Mouse Model of Alzheimer's Disease with Transplanted Stem-Cell-Derived Human Neurons

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Neuroscience Bulletin 2017年第6期33卷 766-768页

作者： yuankai Zhu Hong Zhang Department of Nuclear Medicine The Second Hospital of Zhejiang University School of MedicineHangzhou 310009China Zhejiang University Medical PET Center Hangzhou 310009China Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University Hangzhou 310009China Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou 310009China

Alzheimer’s disease（AD）,the main cause of dementia,is defined by the combined presence of amyloid-b（Ab）deposition and abnormal tau aggregation[1].Experimental models are critical to obtain a better understanding ... 详细信息

关键词： AD A Mouse Model of Alzheimer's Disease with Transplanted Stem-Cell-Derived Human Neurons

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数据加密技术在计算机网络安全中的运用

信息与电脑 2024年第7期36卷 233-235页

作者：陈福群史原恺郑州工业应用技术学院河南郑州451100

本文首先介绍了数据加密技术的基本概念和常见类型,随后详细探讨了数据加密技术在计算机网络安全的多个应用方面,包括数据传输加密、虚拟私人网络的建立、身份验证与数字签名、存储介质与文件加密以及网络数据库加密等,旨在为相关领域... 详细信息

本文首先介绍了数据加密技术的基本概念和常见类型,随后详细探讨了数据加密技术在计算机网络安全的多个应用方面,包括数据传输加密、虚拟私人网络的建立、身份验证与数字签名、存储介质与文件加密以及网络数据库加密等,旨在为相关领域的研究人员和实践者提供关于数据加密技术在计算机网络安全中运用的全面理解和实践指导。

关键词：数据加密技术计算机网络安全