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顶空-气相色谱法同时测定口罩中甲醛和环氧乙烷的含量

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福建分析测试 2024年第3期33卷 42-45,50页

作者：孙光举龙岩市产品质量检验所福建龙岩364000

采用顶空-气相色谱法同时测定口罩中甲醛和环氧乙烷的含量。顶空平衡温度为70℃,平衡时间为20 min,InertCap AQUATIC色谱柱分离,氢火焰离子化检测器(FID)检测,以外标法定量。甲醛和环氧乙烷质量分数在1.00~100μg/g范围内与其对应的峰... 详细信息

采用顶空-气相色谱法同时测定口罩中甲醛和环氧乙烷的含量。顶空平衡温度为70℃,平衡时间为20 min,InertCap AQUATIC色谱柱分离,氢火焰离子化检测器(FID)检测,以外标法定量。甲醛和环氧乙烷质量分数在1.00~100μg/g范围内与其对应的峰面积呈线性关系,按照取样量1.0 g计算,甲醛方法定量限为1.0μg/g,回归方程相关系数0.9994;环氧乙烷方法定量限为1.8μg/g,回归方程相关系数0.9990,相对标准偏差(RSD)(n=6)小于5.0%。二者以空白样品为基质制得加标样品,在3个浓度水平进行加标回收试验,加标回收率均在90%~110%之间。本方法操作简便、快速、准确和稳定,适用于口罩中甲醛和环氧乙烷含量的同时测定。

关键词：甲醛环氧乙烷顶空-气相色谱法口罩

沙库巴曲缬沙坦钠对冠心病合并心力衰竭患者的治疗效果分析

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中国实用医药 2024年第11期19卷 1-5页

作者：孙广远阳谷县人民医院心内科一区 252300

目的分析冠心病合并心力衰竭患者使用沙库巴曲缬沙坦钠治疗的效果。方法84例冠心病合并心力衰竭患者,通过随机抽样法分为常规组和研究组,各42例。常规组、研究组分别采用常规药物治疗和常规药物+沙库巴曲缬沙坦钠治疗。比较两组患者治... 详细信息

目的分析冠心病合并心力衰竭患者使用沙库巴曲缬沙坦钠治疗的效果。方法84例冠心病合并心力衰竭患者,通过随机抽样法分为常规组和研究组,各42例。常规组、研究组分别采用常规药物治疗和常规药物+沙库巴曲缬沙坦钠治疗。比较两组患者治疗效果、心功能指标、运动耐量、血压、生活质量及血清氨基末端B型脑钠肽前体、心型脂肪酸结合蛋白水平。结果研究组总有效率为97.62%,高于常规组的80.95%,存在统计学意义(P<0.05)。研究组治疗后脑钠肽水平(210.11±25.13)pg/ml低于常规组的(246.53±22.87)pg/ml,左室射血分数(56.92±2.93)%及每搏量(52.48±3.37)ml大于常规组的(52.55±2.44)%、(47.43±2.76)ml,左室收缩末期内径(33.65±2.17)mm、左室舒张末期内径(49.61±3.74)mm小于常规组的(38.98±2.13)、(54.97±3.52)mm,存在统计学意义(P<0.05)。研究组治疗后6 min步行距离(195.98±36.41)m大于常规组的(165.84±33.65)m,收缩压(115.05±12.11)mm Hg(1 mm Hg=0.133 kPa)和舒张压(84.05±7.21)mm Hg均低于常规组的(126.74±12.31)、(90.56±8.78)mm Hg,存在统计学意义(P<0.05)。研究组治疗后血清氨基末端B型脑钠肽前体(422.60±34.01)pg/ml及心型脂肪酸结合蛋白(30.46±9.71)ng/ml均低于常规组的(501.39±34.29)pg/ml、(40.25±10.12)ng/ml,存在统计学意义(P<0.05)。研究组心理功能、躯体功能、社会功能、物质生活评分及总分分别为(95.67±4.21)、(91.45±7.38)、(95.45±2.56)、(90.64±7.37)、(373.21±4.85)分,均高于常规组的(75.58±7.24)、(78.03±7.31)、(76.70±6.29)、(70.50±6.76)、(300.81±6.85)分,存在统计学意义(P<0.05)。结论为冠心病合并心力衰竭患者使用沙库巴曲缬沙坦钠进行治疗,可以改善患者心功能水平,能够增强患者运动耐量,降低血压水平,疗效显著,临床应用价值较高。

关键词：沙库巴曲缬沙坦钠冠心病心力衰竭

A Distributed LRTCO Algorithm in Large-Scale DVE Multimedia Systems

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Computers, Materials & Continua 2018年第7期56卷 73-89页

作者： Hangjun Zhou guang sun Sha Fu Wangdong Jiang Tingting Xie Danqing Duan Hunan University of Finance and Economy Fenglin RoadNo.139Changsha410205China Nanjing University of Science and Technology Xiaolingwei RoadNo.200Nanjing210094China School of Electrical Engineering and Computer Science Queen Mary University of LondonMile End RdLondon E14NSUK

In the large-scale Distributed Virtual Environment(DVE)multimedia systems,one of key challenges is to distributedly preserve causal order delivery of messages in real time.Most of the existing causal order control approaches with real-time constraints use vector time as causal control information which is closely coupled with system scales.As the scale expands,each message is attached a large amount of control information that introduces too much network transmission overhead to maintain the real-time causal order delivery.In this article,a novel Lightweight Real-Time Causal Order(LRTCO)algorithm is proposed for large-scale DVE multimedia systems.LRTCO predicts and compares the network transmission times of messages so as to select the proper causal control information of which the amount is dynamically adapted to the network latency variations and unconcerned with system scales.The control information in LRTCO is effective to preserve causal order delivery of messages and lightweight to maintain the real-time property of DVE systems.Experimental results demonstrate that LRTCO costs low transmission overhead and communication bandwidth,reduces causal order violations efficiently,and improves the scalability of DVE systems.

关键词： Distributed computing distributed virtual environment multimedia system causality violation causal order delivery real time

Expanding Hot Code Path for Data Cleaning on Software Graph

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Computers, Materials & Continua 2020年第5期63卷 743-753页

作者： guang sun Xiaoping Fan Wangdong Jiang Hangjun Zhou Fenghua Li Rong Yang Institute of Big Data Hunan University of Finance and EconomicsChangsha410205China School of Engineering University of AlabamaTuscaloosa35487USA

Graph analysis can be done at scale by using Spark GraphX which loading data into memory and running graph analysis in parallel.In this way,we should take data out of graph databases and put it into memory.Considering the limitation of memory size,the premise of accelerating graph analytical process reduces the graph data to a suitable size without too much loss of similarity to the original graph.This paper presents our method of data cleaning on the software graph.We use SEQUITUR data compression algorithm to find out hot code path and store it as a whole paths directed acyclic graph.Hot code path is inherent regularity of a program.About 10 to 200 hot code path account for 40%-99%of a program’s execution cost.These hot paths are acyclic contribute more than 0.1%-1.0%of some execution metric.We expand hot code path to a suitable size which is good for runtime and keeps similarity to the original graph.

关键词： Hot code path expanded hot path software graph software graph

Design and Analysis of a Water Quality Monitoring Data Service Platform

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Computers, Materials & Continua 2021年第1期66卷 389-405页

作者： Jianjun Zhang Yifu Sheng Weida Chen Haijun Lin guang sun Peng Guo College of Engineering and Design Hunan Normal UniversityChangsha410081China Zhaoyin Network Technology(Shenzhen)Co. Ltd.Shenzhen518057China Big Data Institute Hunan University of Finance and EconomicsChangsha410205China University Malaysia Sabah Sabah88400Malaysia

Water is one of the basic resources for human survival.Water pollution monitoring and protection have been becoming a major problem for many countries all over the world.Most traditional water quality monitoring systems,however,generally focus only on water quality data collection,ignoring data analysis and data mining.In addition,some dirty data and data loss may occur due to power failures or transmission failures,further affecting data analysis and its application.In order to meet these needs,by using Internet of things,cloud computing,and big data technologies,we designed and implemented a water quality monitoring data intelligent service platform in C#and PHP language.The platform includes monitoring point addition,monitoring point map labeling,monitoring data uploading,monitoring data processing,early warning of exceeding the standard of monitoring indicators,and other functions modules.Using this platform,we can realize the automatic collection of water quality monitoring data,data cleaning,data analysis,intelligent early warning and early warning information push,and other functions.For better security and convenience,we deployed the system in the Tencent Cloud and tested it.The testing results showed that the data analysis platform could run well and will provide decision support for water resource protection.

关键词： Water quality monitoring data analysis big data tencent cloud

Free-walking:Pedestrian inertial navigation based on dual foot-mounted IMU

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Defence Technology（防务技术） 2024年第3期33卷 573-587页

作者： Qu Wang Meixia Fu Jianquan Wang Lei sun Rong Huang Xianda Li Zhuqing Jiang Yan Huang Changhui Jiang School of Automation Science and Electrical Engineering University of Science and Technology BeijingBeijing100083China Shunde Innovation School University of Science and Technology BeijingFo Shan528399China Research Institute of China Unicom Beijing100190China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing100876China Department of Automation Tsinghua University Beijing100084China GEOLOC Laboratory Universite Gustave EiffelParis77454France

The inertial navigation system(INS),which is frequently used in emergency rescue operations and other situations,has the benefits of not relying on infrastructure,high positioning frequency,and strong real-time performance.However,the intricate and unpredictable pedestrian motion patterns lead the INS localization error to significantly diverge with time.This paper aims to enhance the accuracy of zero-velocity interval(ZVI)detection and reduce the heading and altitude drift of foot-mounted INS via deep learning and equation constraint of dual feet.Aiming at the observational noise problem of low-cost inertial sensors,we utilize a denoising autoencoder to automatically eliminate the inherent noise.Aiming at the problem that inaccurate detection of the ZVI detection results in obvious displacement error,we propose a sample-level ZVI detection algorithm based on the U-Net neural network,which effectively solves the problem of mislabeling caused by sliding windows.Aiming at the problem that Zero-Velocity Update(ZUPT)cannot suppress heading and altitude error,we propose a bipedal INS method based on the equation constraint and ellipsoid constraint,which uses foot-to-foot distance as a new observation to correct heading and altitude error.We conduct extensive and well-designed experiments to evaluate the performance of the proposed method.The experimental results indicate that the position error of our proposed method did not exceed 0.83% of the total traveled distance.

关键词： Indoor positioning Inertial navigation system(INS) Zero-velocity update(ZUPT) Internet of things(IoTs) Location-based service(LBS)

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畅流活水净化动力学行为分析

科学技术与工程 2024年第11期24卷 4800-4810页

作者：靳垚孙洪广王连河海大学力学与材料学院南京210098

针对河道和湖泊水质净化处理问题,从水动力学方面优化水体自身的水质净化能力,基于FLUENT软件分别建立二维和三维水动力模型,模拟注水过程中流场的变化,以流场中流速、压力以及湍流强度为指标,研究不同注水位置对水质自净化过程的影响... 详细信息

针对河道和湖泊水质净化处理问题,从水动力学方面优化水体自身的水质净化能力,基于FLUENT软件分别建立二维和三维水动力模型,模拟注水过程中流场的变化,以流场中流速、压力以及湍流强度为指标,研究不同注水位置对水质自净化过程的影响。结果表明:在深度方向上,随着进水口位置的下移,流场活跃范围减小,死区增多;在流动方向,流动距离越远,流场湍流强度越大;在宽度方向,流场流速,压力和湍流强度均以中间进水口的纵向截面对称,流速主要集中在进水口主流区,以及末端的回流处。进水口越接近上部,对于水体的自净化促进效果越好,建议采用上部注水方式来促进河道自净化。研究结果可对促进河道水质自净化提供参考和建议。

关键词：水质净化水动力模拟 FLUENT 结构优化高维模拟

Stock Price Forecasting: An Echo State Network Approach

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Computer Systems Science & Engineering 2021年第3期36卷 509-520页

作者： guang sun Jingjing Lin Chen Yang Xiangyang Yin Ziyu Li Peng Guo Junqi sun Xiaoping Fan Bin Pan Hunan University of Finance and Economics ChangshaChina University Malaysia Sabah Kota KinabaluMalaysia Yali High School International Department ChangshaChina

Forecasting stock prices using deep learning models suffers from pro-blems such as low accuracy,slow convergence,and complex network structures.This study developed an echo state network(ESN)model to mitigate such pro-blems.We compared our ESN with a long short-term memory(LSTM)network by forecasting the stock data of Kweichow Moutai,a leading enterprise in China’s liquor industry.By analyzing data for 120,240,and 300 days,we generated fore-cast data for the next 40,80,and 100 days,respectively,using both ESN and LSTM.In terms of accuracy,ESN had the unique advantage of capturing non-linear data.Mean absolute error(MAE)was used to present the accuracy results.The MAEs of the data forecast by ESN were 0.024,0.024,and 0.025,which were,respectively,0.065,0.007,and 0.009 less than those of LSTM.In terms of con-vergence,ESN has a reservoir state-space structure,which makes it perform faster than other models.Root-mean-square error(RMSE)was used to present the con-vergence time.In our experiment,the RMSEs of ESN were 0.22,0.27,and 0.26,which were,respectively,0.08,0.01,and 0.12 less than those of LSTM.In terms of network structure,ESN consists only of input,reservoir,and output spaces,making it a much simpler model than the others.The proposed ESN was found to be an effective model that,compared to others,converges faster,forecasts more accurately,and builds time-series analyses more easily.

关键词： Stock data forecast echo state network deep learning

协同与建构:新时代中小学劳动课程实施的逻辑理路

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黑龙江教师发展学院学报 2024年第7期43卷 116-120页

作者：孙荣李光汉江师范学院教育学院湖北十堰442000

多元课程实施主体与劳动课程本身及其诸要素之间的关系,构成了新时代中小学劳动课程实施的逻辑理路。按照课程实施“采用—调适—应用”的内部发生机制,中小学实施劳动课程的价值逻辑在于明确多元主体的价值取向,平衡课程主体间的价值诉... 详细信息

多元课程实施主体与劳动课程本身及其诸要素之间的关系,构成了新时代中小学劳动课程实施的逻辑理路。按照课程实施“采用—调适—应用”的内部发生机制,中小学实施劳动课程的价值逻辑在于明确多元主体的价值取向,平衡课程主体间的价值诉求,形成构筑劳动课程实施良性生态系统的价值愿景;建构逻辑在于对劳动课程进行指向“五育融合”教育体系,符合新时代劳动格局,适应中小学教学实践的课程调适;行动逻辑在于组建以班主任为中心的劳动教育共同体,有序开发层级化劳动课程资源,建构多维情境化劳动教育实践场域。

关键词：中小学劳动教育劳动课程课程实施逻辑理路