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基于ARIMA模型在美国COVID-19累计确诊人数中的应用
Based on the Application of the ARIMA Model in the Cumulative Number of Confirmed Cases of COVID-19 in the United States  [PDF]
谢旺, 牟银, 宋佳硕
Statistics and Applications (SA) , 2020, DOI: 10.12677/SA.2020.96103
Abstract:
本文针对新型冠状病毒肺炎给世界人民造成的不良影响，收集2020年1月20日~2020年6月1日内以美国为主的各个国家和地区每日COVID-19累计确诊人数，建立自回归求和滑动平均(auto regressive integrated moving average, ARIMA)模型对美国累计确诊人数进行分析与预测，用SPSS25.0和MATLAB2019a拟合，结合拟合优度R2和Q检验评价拟合效果，将后5日累计确诊人数预测值和真实值进行比较，评价该模型预测精度及预测美国未来10日累计确诊人数。结果表明，原始序列经2次差分后能较好拟合ARIMA (0,2,1)模型，R2在0.95以上，Q检验p值为0.19 > 0.05，认为残差为白噪声，且预测值与实际值动态趋势基本一致，预测值在真实值0.33%误差内波动，ARIMA (0,2,1)模型对美国COVID-19累计确诊人数预测精度很高，对疫情防控具有很强的指导意义。
To address the adverse impact of COVID-19 on people around the world, this article collected the cumulative number of daily COVID-19 diagnosed in countries and territories, mainly the United States, from January 20 to June 1, 2020. Auto Regressive Integrated Moving Average Model (ARIMA) was established to analyze and predict the cumulative number of diagnosed cases in the United States. With SPSS25.0 and MATLAB2019a as fitting methods, combined with the R2 and Q test to evaluate the fitting effect, the predicted and real values for the cumulative number of confirmed cases for the last 5 days were compared to evaluate the prediction accuracy of the model and the cumulative number of confirmed cases for the next 10 days. The results show that the original sequence can fit the ARIMA (0,2,1) model well after two differences. The R2 is above 0.95, and the p value of the Q test is 0.19 > 0.05 that is regarded as white noise, and the predicted value is basically consistent with the actual value dynamic trend. The forecast value fluctuated within 0.33% of the true value. The ARIMA (0,2,1) model is under a high accuracy in predicting the number of COVID-19 diagnosed in the United States, which has a strong guiding significance for epidemic prevention and control.
广义B样条曲线及其节点插入算法
谢伟松,张硕
华东理工大学学报 , 2007,
Abstract: 通过二阶常系数微分算子的零空间及其初值问题解的唯一性,引入了广义B样条曲线的概念,给出了B样条曲线的一种统一表示形式,介绍了该样条的求值算法及节点插入算法,并对其凸包性质和变差缩减性质作了分析,最后给出了相应算例。数值实验表明:该算法对任意样条都适用,且结果准确、有效。
中国企业研发国际化研究的综述与展望
王展硕,谢伟
- , 2017,
Abstract: 中国企业从20世纪90年代开始积极走出去开展国际化的研发活动，监测、追踪、学习、转移国外先进的技术和知识，提升自身研发实力和市场竞争力.本文对过去20年中国企业研发国际化领域的重点文献进行综述，从研发国际化的动因、影响因素、区位选择、进入模式、组织形式和创新绩效等6个方面进行框架性研究，分析了中西方学者既有研究的特点和缺陷，比较中国企业与西方企业研发国际化行为的差异，同时为未来学术研究指出5个方向的展望.
研发国际化对企业创新绩效的作用过程及结果分析
王展硕,谢伟
- , 2018, DOI: 10.16538/j.cnki.fem.2018.09.005
Abstract: 随着研发国际化逐渐成为跨国企业获取技术资源、提升研发实力、开拓海外市场的重要途径，研发国际化与企业创新绩效关系的研究得到学术界和商业界的共同关注。本文梳理了20世纪90年代以来的学术研究成果，有效整合知识基础观、社会嵌入性、组织学习和制度理论等多个理论视角，提出了研发国际化对于企业创新绩效作用过程的整合框架，包括了外部嵌入接收知识外溢、内部嵌入实现知识逆向转移、知识吸收与整合创新。此外，由于分散运营和外来者劣势，研发国际化也会给企业创新绩效带来消极影响。本文系统回顾了已有的实证研究成果，梳理研发国际化与创新绩效的关系和影响因素，并对未来的研究从内外部嵌入性、进入阻碍、新情境和新对象四个角度提出展望。
生物保鲜技术在海产品中的应用及展望
刘爱芳,王硕,谢晶
包装工程 , 2017,
Abstract: 目的 总结生物保鲜技术在海产品中的研究现状和未来的发展方向，为海产品保鲜研究的应用提供相关参考。方法 首先分类概述生物保鲜剂，然后分别介绍茶多酚、乳酸链球菌素、壳聚糖、溶菌酶等不同来源的生物保鲜剂及复合生物保鲜剂在海产品及其制品保鲜中的应用现状及进展，以及生物保鲜剂与冰温保鲜、气调保鲜等其他保鲜手段结合的协同保鲜效果。指出目前国内海产品保鲜上存在的一些问题及今后的发展方向。结果 生物保鲜技术通过应用天然物质固有的抗菌化合物来延长保鲜期。生物保鲜剂的研究成果推动了海产品市场的发展，提高了海产品的经济价值。结论 生物保鲜剂，尤其是复合保鲜剂结合其他保鲜方法能有效地保障海产品品质，延长货架期
渣油加氢裂化膨胀床反应器反应性能模拟
王硕;谢六磊;刘辉*
- , 2013,
Abstract: 针对渣油加氢裂化这一复杂多相反应体系，建立了包含传质和反应的多相膨胀床反应器模型。基于模拟重点考察了反应温度以及反应器床层内填装不同外形催化剂对反应器出口中间馏分油质量收率的影响。结果表明：（1）在所模拟的温度范围内，取反应温度为693K时，中间馏分油出口质量收率最大，为75.02%；（2）在反应器内分别填装不同形状催化剂时，反应器出口中间馏分油的质量收率不同，其中当填装四叶草形催化剂时，中间馏分油质量收率最大，为81.42%。
Fe73.4Cu1Nb3Si13.5B9Al0.1纳米晶合金制备及其软磁性能
朱正吼,谢文硕
- , 2016, DOI: 10.3969/j.issn.1001-9731.2016.01.047
Abstract: 首先制备了Fe73.4Cu1Nb3Si13.5B9Al0.1非晶合金带材并研究了微量Al在Fe73.4Cu1Nb3Si13.5B9-Al0.1纳米晶合金中的影响情况。研究表明,微量的Al降低了Fe73.4Cu1Nb3Si13.5B9Al0.1母合金的流动性;微量的Al促使Fe73.4Cu1Nb3Si13.5B9Al0.1非晶合金在晶化热处理时的晶粒显著长大,降低了非晶合金中的内应力各向异性,由此提高了其晶化后的纳米晶合金100 kHz以上频率的μe值,同时也显著降低其获得最佳软磁性能的晶化处理温度;晶化处理后,Al原子在Fe73.4Cu1Nb3Si13.5B9Al0.1纳米晶合金中富集于α-Fe晶粒和富铜团簇内并且有可能形成了Fe3Al;Fe73.4Cu1-Nb3Si13.5B9Al0.1磁芯的最佳晶化处理工艺是545 ℃×1 h,其磁芯在1,10,100和200 kHz时的μe值分别为33 785,21 551,9 884和5 444
非惯性系下质点的运动规律研究
Study on the Motion Law of Particles in Non-Inertial System  [PDF]
刘敏, 程利霞, 曾子芳, 谢卫东, 孙光东, 冯硕
International Journal of Mechanics Research (IJM) , 2020, DOI: 10.12677/IJM.2020.92004
Abstract: 力学教科书中，依据牛顿运动定律仅推导出了在惯性系和“特殊非惯性系”(质心系)下质点运动定理及其相应守恒定律的数学表达形式。为了便于在“一般非惯性系”下研究质点的运动规律，本文基于牛顿运动定律，推导出了“一般非惯性系”下质点的动量定理、动能定理、角动量定理及其相应守恒定律的数学表达形式。
In mechanics textbook, according to Newton’s law motion, only the mathematical expression of particle motion theorem and its corresponding conservation law in inertial system and “special Non-Inertial system” (center of mass system) are deduced. In order to study the motion law of particle in “general Non-Inertial system”, based on Newton’s law of motion, this paper deduces the momentum theorem, kinetic energy theorem, angular momentum theorem of particles in “general Non-Inertial system” and their corresponding conservation laws.
42例肉芽肿性小叶炎患者的激素水平特征分析
Characteristics of Hormone Levels in 42 Patients with Granulomatous Lobular Mastitis  [PDF]
梅硕, 黄勇, 谢增泽, 李芝, 杨越
Medical Diagnosis (MD) , 2021, DOI: 10.12677/MD.2021.113022
Abstract: 目的：总结并分析肉芽肿性小叶炎患者的激素水平特征，寻求疾病的实验室特征及为激素治疗提供依据。方法：回顾性分析2020年1月至2021年3月在昆明市第一人民医院经过手术病检证实为肉芽肿性小叶炎患者的临床资料，观察其流行病学特征，统计实验室检查结果，评估激素水平是否超过正常参考值范围。结果：共纳入42例病理学诊断为肉芽肿性小叶炎的患者，42例患者均处在正常月经周期内。手术前抽血检查，其中32例患者处于卵泡期，10例患者处于黄体期。卵泡期雌激素通过实验样本的均数值与总体正常人群的均数值的t检验结果，不拒绝H0，两者的差别无统计学意义，但黄体期雌激素水平通过t检验，两者差别具有统计学意义。泌乳素根据通过实验样本的均数值与总体正常人群的均数值的t检验结果，两者的差别具有统计学意义，呈阳性结果。结论：肉芽肿性小叶炎患者的雌激素水平在卵泡期较正常人群无明显差异，而在黄体期较正常人群存在统计学差异(较正常偏低)，泌乳素水平则与正常人群具有显著的统计学差异，表明雌激素水平的变化及泌乳素水平的增高可能影响到疾病的发生。
Purpose: Summarize and analyze the characteristics of hormone levels in patients with granulomatous lobular mastitis to discover the laboratory characteristics of the disease and provide the basis for hormone therapy. Method: Retrospective analysis was performed on the clinical data of patients with granulomatous lobular mastitis confirmed by after surgery pathological test in the First People’s Hospital of Kunming from January 2020 to March 2021. The epidemiological characteristics were observed while the results of laboratory tests were counted to assess whether the hormone levels exceeded the normal reference range. Result: A total of 42 patients with pathologically diagnosed granulomatous lobular mastitis were included. When all patients take the before-surgery blood test, of 42 patients who were in normal menstrual cycles, 32 patients were in the follicular stage and 10 patients were in the beta phase. T-test was conducted between the mean values of the experimental samples and the normal population. The result of estrogen level in the follicular stage did not reject H0, and the difference between the two was not statistically. But the result of estrogen level in the beta phase did reject H0, the difference between the two was statistically significant. The difference in prolactin level between the two groups was statistically significant and the prolactin results are positive. Conclusion: For the estrogen levels with granulomatous lobular mastitis. There was no significant difference in the follicular stage, but in the beta phase, there were statistically significant differences (lower than the normal population), and the prolactin level was significantly different from the normal population. These may indicate that the estrogen level and the prolactin level may affect the disease.
职场排斥对员工沉默行为的影响：情绪耗竭的中介作用
The Effect of Workplace Exclusion on Employees’ Silent Behavior: The Mediating Effect of Emotional Exhaustion  [PDF]
程硕硕
Advances in Psychology (AP) , 2020, DOI: 10.12677/AP.2020.105078
Abstract:
职场排斥是员工在职场中所体验到的一种复杂的人际冲突，往往会导致员工出现一些回避反应，例如员工的沉默行为。以往的研究主要关注职场排斥与员工沉默行为的认知因素，而有关情绪因素对员工造成的影响则较少受到关注。本研究选取222名在职员工作为本次研究的研究对象，通过职场排斥对员工沉默行为的基本框架，从情绪路径对上述关系中情绪耗竭的中介作用进行研究。研究结果表明：职场排斥能够正向预测员工的三种沉默行为；情绪耗竭在职场排斥与员工的三种沉默行为之间起到部分中介作用。基于此，组织和领导者应注意引导建立和谐的职场工作氛围，关注员工情绪对于员工沉默行为的影响，促使员工积极建言。
Workplace rejection is a complex interpersonal conflict experienced by employees in the workplace, which often leads to some avoidance and retaliation reactions, such as the silent behavior of employees. Previous studies have focused on the cognitive factors of workplace rejection and silent behavior, while less attention has been paid to the impact of emotional factors on employees. In this study, 222 on-the-job employees were selected as the research objects, and the mediating role of emotional exhaustion in the above relationships was studied from the perspective of emotional pathways through the basic framework of workplace exclusion and silent behavior of employees. The results show that workplace rejection can positively predict three kinds of silent behaviors of employees. Emotional exhaustion in the workplace exclusion and three kinds of silent behavior of employees play a part in the mediating role. Based on this, organizations and leaders should pay attention to guide the establishment of a harmonious workplace work atmosphere, pay attention to the influence of employees’ emotions on their silent behavior, and encourage employees to make positive suggestions.
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