Trend Autoregressive Model Exact Run Length Evaluation on a Two-Sided Extended EWMA Chart

The Extended Exponentially Weighted Moving Average(extended EWMA)control chart is one of the control charts and can be used to quickly detect a small shift.The performance of control charts can be evaluated with the average run length(ARL).Due to the deriving explicit formulas for the ARL on a two-sided extended EWMA control chart for trend autoregressive or trend AR(p)model has not been reported previously.The aim of this study is to derive the explicit formulas for the ARL on a two-sided extended EWMA con-trol chart for the trend AR(p)model as well as the trend AR(1)and trend AR(2)models with exponential white noise.The analytical solution accuracy was obtained with the extended EWMA control chart and was compared to the numer-ical integral equation(NIE)method.The results show that the ARL obtained by the explicit formula and the NIE method is hardly different,but the explicit for-mula can help decrease the computational(CPU)time.Furthermore,this is also expanded to comparative performance with the Exponentially Weighted Moving Average(EWMA)control chart.The performance of the extended EWMA control chart is better than the EWMA control chart for all situations,both the trend AR(1)and trend AR(2)models.Finally,the analytical solution of ARL is applied to real-world data in the healthfield,such as COVID-19 data in the United Kingdom and Sweden,to demonstrate the efficacy of the proposed method.

Decreasing Trend in Global Land Monsoon Precipitation over the Past 50 Years Simulated by a Coupled Climate Model

The authors examine the effects of external forcing agents such as greenhouse gases （GHGs） and aerosols, as well as solar variability and ozone, on global land monsoon precipitation by using a coupled climate model HadGEM1, which was developed by the Met Office Hadley Centre for Climate Research. The results indicate that HadGEM1 performs well in simulating the observed decreasing trend of global land monsoon precipitation over the past 50 years. This trend mainly occurred in the Northern Hemisphere and is significantly different from the trend of natural variability due to ocean-atmosphere-land interactions. The coherence between the simulation and the observations indicates that the specified external forcing agents, including GHGs and aerosols as well as solar variability and ozone, are important factors that have affected the decreasing trend of global land monsoon precipitation in the past 50 years.

A Statistical Model for Investigating Climatic Trend Turning Points

A two-phase trend model is presented to investigate the turning-point signals of evolution trend in long-term series of a climatic element. Based on nonlinear fitting, the revised model brings out more evident improvement of the linear model proposed by Solow et al. (1987). Both theoretical deduction and case calculation show that our version can search the turning point and period accurately and objectively. In particular it is fit for computer exploring the turning points in long-range records from stations covering a large area, thus avoiding subjective judgement by a usual drawing method.

Evolution History and Development Trend of Industrialized Live Pig Breeding Model in China

Tremendous achievements of live pig industry in China are closely related to the industrialization of the industry,and development trend of the latter is essential for maintaining sustained and stable development of animal husbandry.The paper,on the basis of defining the evolution of industrialized live pig breeding model,elaborated the industrialized operation models of live pig industry in China since 1978,i.e.household operation,large-scale operation,and industrialized operation.The external environment for the development of live pig industry was analyzed,such as global economic competition,development of experience economy,and stronger green consciousness of consumers.Then development trend of industrialized live pig breeding was analyzed as"expanding international market,consolidating domestic market,integrating resources of live pig industry for the integrated operation,promoting the industrialization model and breeding technology driven by live pig processing,applying animal welfare and the internet of things in live pig breeding industry".

Human settlement's social network analysis based on spatial trend surface model:a case study of Chongqing Municipality

Integrated with GIS and remote sensing(RS) technology,a systematic analysis and its methodology for human-settlements social environment has been introduced.This methodology has been called spatial trend field model(STFM).STFM's application history in the field of human-settlements social environment has been discussed at first.Then,some index data models have been created through STFM,which include population density trend field,human activity strength trend field,city-town spatial density trend field,urbanization ratio trend field,road density trend field,GDP spatial density trend field and PER-GDP spatial density trend field.With all above-mentioned indexes as input data,through Iterative Self-Organizing Data Analysis Techniques Algorithm(ISODATA),this paper makes a verification study of Chongqing municipality.The result of the case study confirms that STFM methodology is credible and has high efficiency for regional human-settlements study.

2000—2021年如东县2型糖尿病发病趋势分析

目的:分析2000—2021年如东县2型糖尿病发病趋势,为政府制定糖尿病防控策略提供科学依据。方法:收集2000—2021年如东县区域卫生信息平台和医院信息系统(HIS)中的新发2型糖尿病病例,采用Joinpoint回归模型分析2型糖尿病发病率变化特征,计算年度变化百分比(APC)和平均年度变化百分比(AAPC),预测并验证2022年糖尿病发病水平。结果:2000—2021年如东县2型糖尿病平均粗发病率为259.75/10万,标化发病率总体呈上升趋势,从2000年的51.27/10万上升到2021年的139.83/10万,AAPC为7.76%;2012年是发病率变化转折点,2000—2012年APC=18.67%,2型糖尿病发病率快速上升;2012—2021年APC=-5.24%,发病率缓慢下降。男性粗发病率为198.07/10万,标化率为118.73/10万;女性粗发病率为318.89/10万,标化率为197.03/10万。女性发病率高于男性,差异有统计学意义(Z=4.41,P<0.05)。45~74岁人群2型糖尿病发病率呈波动性变化。结论:2000—2021年如东县2型糖尿病发病率总体先上升后缓慢下降,糖尿病仍是如东县实施综合防控策略的主要慢性病,女性、45~74岁人群是该地区2型糖尿病重点防控对象。

Grey GM(1,1) Model with Function-Transfer Method for Wear Trend Prediction and its Application

Trend forecasting is an important aspect in fault diagnosis and work state supervision. The principle, where Grey theory is applied in fault forecasting, is that the forecast system is considered as a Grey system; the existing known information is used to infer the unknown information's character, state and development trend in a fault pattern, and to make possible forecasting and decisions for future development. It involves the whitenization of a Grey process. But the traditional equal time interval Grey GM (1,1) model requires equal interval data and needs to bring about accumulating addition generation and reversion calculations. Its calculation is very complex. However, the non equal interval Grey GM (1,1) model decreases the condition of the primitive data when establishing a model, but its requirement is still higher and the data were pre processed. The abrasion primitive data of plant could not always satisfy these modeling requirements. Therefore, it establishes a division method suited for general data modeling and estimating parameters of GM (1,1), the standard error coefficient that was applied to judge accuracy height of the model was put forward; further, the function transform to forecast plant abrasion trend and assess GM (1,1) parameter was established. These two models need not pre process the primitive data. It is not only suited for equal interval data modeling, but also for non equal interval data modeling. Its calculation is simple and convenient to use. The oil spectrum analysis acted as an example. The two GM (1,1) models put forward in this paper and the new information model and its comprehensive usage were investigated. The example shows that the two models are simple and practical, and worth expanding and applying in plant fault diagnosis.

Modeling Rainfall Intensity-Duration-Frequency (IDF) and Establishing Climate Change Existence in Uyo-Nigeria Using Non-Stationary Approach

This study aims at establishing if climate change exists in the Niger Delta environment using non-stationary rainfall Intensity-Duration-Frequency (IDF) modelling incorporating time-variant parameters. To compute the intensity levels, the open-access R-studio software was used based on the General Extreme Value (GEV) distribution function. Among the four linear parameter models adopted for integrating time as a covariate, the fourth linear model incorporating scale and location with the shape function constant produced the least corrected Akaike Information Criteria (AICc), varying between 306.191 to 101.497 for 15 and 1440 minutes, respectively, selected for calibration of the GEV distribution equation. The non-stationary intensities yielded higher values above those of stationary models, proving that the assumption of stationary IDF models underestimated extreme events. The difference of 13.71 mm/hr (22.71%) to 14.26 mm/hr (17.0%) intensities implies an underestimation of the peak flood from a stationary IDF curve. The statistical difference at a 95% confidence level between stationary and non-stationary models was significant, confirming evidence of climatic change influenced by time-variant parameters. Consequently, emphasis should be on applying shorter-duration storms for design purposes occurring with higher intensities to help reduce the flood risk and resultant infrastructural failures.

应用时空复合趋势面Kriging方法插值地表沉降

通过布设监测点可反映地表沉降变化趋势,确保施工和运营期间安全,但沉降监测点数量有限,且易受施工作业、天气等因素干扰导致数据缺失或污染,因此需对监测区域数据进行插值处理。针对采用传统地统计插值方法估计地铁地表沉降趋势精度较低的问题,提出了一种基于时空复合趋势面的Kriging插值方法。以乌鲁木齐地铁3号线2017年6月24日—9月3日共15期地铁地表沉降观测值为实验数据,分别采用两种方法对沉降监测点缺失数据进行插补。结果表明,相较于传统方法,基于时空复合趋势面的Kriging插值方法的拟合精度更高,RMSE可降低约35%。

工业智能化对劳动收入的影响——基于随机趋势模型的估计

本文基于构建的2005~2017年省级面板数据,应用随机趋势模型估计了工业智能化对劳动收入的影响。结果表明,当前工业智能化对劳动收入总的影响是稍显正向的,但存在明显的阶段性特征和滞后效应。以2012年为分界点,2005~2011年工业智能化对劳动收入的影响是显著负向的,2012~2017年该影响则是显著正向的;而且工业智能化变量滞后项的估计系数显著。此外,估计结果还表明,由于各地区经济发展水平和工业规模不同以及工业智能化对其他行业的外溢影响不同,工业智能化对劳动收入的影响存在明显的地域差异和行业差异。本文对工业智能化的劳动收入效应及其影响过程的分析为后续相关产业和劳动力市场政策的制定与完善提供了实证参考依据。

考虑特征重组与改进Transformer的风电功率短期日前预测方法

短期日前风电功率预测对电力系统调度计划制定有重要意义,该文为提高风电功率预测的准确性,提出了一种基于Transformer的预测模型Powerformer。模型通过因果注意力机制挖掘序列的时序依赖;通过去平稳化模块优化因果注意力以提高数据本身的可预测性;通过设计趋势增强和周期增强模块提高模型的预测能力;通过改进解码器的多头注意力层,使模型提取周期特征和趋势特征。该文首先对风电数据进行预处理,采用完全自适应噪声集合经验模态分解(complete ensemble empirical mode decomposition with adaptive noise,CEEMDAN)将风电数据序列分解为不同频率的本征模态函数并计算其样本熵,使得风电功率序列重组为周期序列和趋势序列,然后将序列输入到Powerformer模型,实现对风电功率短期日前准确预测。结果表明,虽然训练时间长于已有预测模型,但Poweformer模型预测精度得到提升;同时,消融实验结果验证了模型各模块的必要性和有效性,具有一定的应用价值。

基于在线评论的乘用车需求趋势分析方法

提出一种基于在线产品评论的竞争情报挖掘方法,将网络评论文本中的关键信息应用于乘用车设计开发中。结合LDA和TF-IDF算法,从主题特征和情感态度特征获取不同车型评论主题情感倾向性估值,并对应2009—2019年的乘用车销量,构建用户偏好分析的面板数据模型。结果显示:该方法能够有效地提取网络评论情报信息;通过与年份的交互作用分析产品需求趋势,过去11年间消费者只对油耗的关注度降低了8.64%,对动力、空间、外观、内饰和舒适性的关注度分别上升了3.16%,6.80%,89.69%,13.38%和18.47%。其中,与生活品质更加密切的外观、内饰和舒适性等指标的增量远高于传统关注的动力和空间指标。这表明燃油经济性越来越不受关注,已不再成为消费者购买乘用车的决定性因素。

低幅构造识别技术研究与应用

针对滨里海盆地东缘阿克若尔构造带低幅度构造识别的问题,开发基于反演层速度法和构造趋势面拟合法的低幅构造识别方法。该方法适用于局部发育速度异常体、速度变化快、斜坡区目的层埋藏深度大且圈闭幅度小的情况;优选构造解释层位趋势和单井速度约束下的层速度反演的方法建立研究区速度模型,对地震层位进行标定,克服了常规层速度反演方法横向连续性的限制,对复杂地层具有更好的适应性;构造趋势面拟合法对研究区低幅构造进行有效识别,克服了因构造幅度低、同相轴平直并且变化幅度小而难以识别的问题,对滨里海东缘深度域构造图进行构造趋势面拟合,取得了较好的效果。

某三甲中医医院ICU感染发生率时间序列分析及趋势预测

目的:了解某三甲中医医院ICU感染发生率的时序分布特征,预测其发生规律和趋势,为中医医院ICU感染监测提供数据支持。方法:收集某三甲中医医院2019年1月至2024年2月ICU医院感染数据。利用求和自回归滑动平均模型(Autoregressive integrated moving average,ARIMA)对ICU感染发生趋势进行预测并评价其预测效果。结果:2019年1月至2024年2月某三甲中医医院ICU医院感染发生率为2.61%(232/8895);时间序列分析显示,ICU医院感染发生率波动较大且存在一定周期性,总体呈下降趋势。根据赤池信息准则和贝叶斯信息准则拟合,ARIMA(0,1,1)为最优预测模型。经参数估计与效果评价,感染发生率实际值均在预测值95%可信区间内,模型预测效果较好。结论:运用ARIMA对某三甲中医医院ICU医院感染发生率的预测结果良好,可显示其长期发生规律与趋势,能为医院感染监测提供科学依据。

1990-2019年中国和美国胰腺癌发病率长期趋势分析

目的:通过对比中国和美国人群胰腺癌发病率的变化趋势,为中国胰腺癌的防控提供有效的建议。方法:基于全球疾病负担(Global Burden of Disease,GBD)2019中1990-2019年中国和美国胰腺癌发病率相关数据,采用美国国家癌症中心提供的Joinpoint软件计算胰腺癌年度百分比变化(annual percentage change,APC)和平均年度百分比变化(average annual percentage change,AAPC)来估计胰腺癌年龄标化发病率的时间趋势,以及采用年龄-时期-队列模型分析工具评估年龄、时期、出生队列对胰腺癌发病率的独立效应。结果:中国胰腺癌发病率增幅高于美国,上升趋势明显高于美国,男性人群发病例数增长约3.4倍,女性约3.1倍。Joinpoint结果显示,中国总人口AAPC为2.1%,男性为2.3%,女性为1.9%。中国与美国胰腺癌发病率的年龄效应均随年龄增长而上升,在85~89岁年龄组时年龄效应最大;时期效应整体随着时期的推移而上升,中国呈明显变化趋势而美国几乎保持稳定;队列效应呈现先上升后波动式下降的趋势,中国男性胰腺癌发病率RR值增长最大。结论:中国人群胰腺癌发病率趋势显著上升,男性发病率大于女性,需要重点加强我国55岁以上男性人群胰腺癌的相关防控。

国际开放同行评审平台的发展趋势及其对中国的建议

[目的/意义]梳理分析国际开放同行评审平台的基本模式与发展趋势,探讨国际开放同行评审平台对中国学术交流和科研治理的启示。[方法/过程]文章首先概述了国际开放同行评审平台的3种基本运营模式,之后通过对这些平台和社区发展动态的深入分析,归纳总结了其发展趋势。在此基础上,结合国际经验与中国科研环境的具体特点,提出了针对中国开放开放同行评审(平台)建设的建议。[结果/结论]国际开放同行评审平台和社区正逐步成为推动科研创新、提升科研质量的重要力量。针对中国现状,文章提出加快建设国际开放同行评审平台和社区的6条建议,包括加强政策引导与制度支持,更新科技出版理念,鼓励案例示范,建设国家开放同行评审基础设施等,以抢占国际学术交流的新阵地。

济阳坳陷常规探明石油地质储量增长规律及未来10年增储趋势

济阳坳陷常规石油领域一直是胜利油田勘探开发主战场,至今已经历了60余年勘探开发,整体进入成熟勘探阶段,但每年仍具有较大的增储规模,这与传统认为的含油气盆地探明石油地质储量增长趋势不一致。济阳坳陷常规探明石油地质储量增长规律如何?未来能否继续保持较强的增储态势?其主要的增储领域有哪些?这些事关胜利油田勘探决策的重要问题亟需研究明确。通过梳理济阳坳陷勘探历程,分析其地质特征、资源条件、探井工作量投入、理论技术、资源序列等勘探要素,揭示济阳坳陷常规石油勘探发现规律,运用“帚状”模型预测法、资源探明速率法等方法预测常规探明石油地质储量增长趋势,结合主要增储领域剖析,明确济阳坳陷常规石油未来增储规模及有利方向。结果表明:济阳坳陷复杂的地质特征、较为雄厚的剩余资源基础决定其勘探对象的多样性、勘探过程的曲折性和勘探历史的长期性;在保证相对稳定的探井工作量投入,持续开展勘探理论及关键技术的攻关,保持相对合理的资源序列等条件下,济阳坳陷常规石油仍能保持较长时期的稳定增储;在当前经济技术条件及勘探投入相对保障的情况下,未来10年济阳坳陷仍可贡献常规探明石油地质储量2.5×10^(8)t左右;指出济阳坳陷新近系河道砂岩油藏、沙四段上亚段—沙三段岩性油气藏等成熟领域仍是稳定增储的压舱石,孔店组—沙四段下亚段深层领域是重要的规模增储领域,前古近系潜山领域是富集高产的有利方向。今后,应紧密跟踪非常规与新能源领域的勘探进展,对济阳坳陷常规探明石油地质储量增长规律及增储趋势等研究结果进行不断地完善和修正,以期更符合油田勘探发展态势,指导油田勘探决策。

轨交站域建成环境评测研究的方向、指标与趋势

建成环境评测是轨交站域城市更新的前提,在新的实践和技术背景下,总结该领域的进展和趋势具有指导意义。从环境行为、指标评价两个方向归纳了轨交站域建成环境评测研究的创新发展与前沿;通过梳理近三十年来的主要文献,探讨了轨交站域建成环境评测指标演进的4个阶段及其特征;最后总结得出认知与评价角度的多元化拓展、评测指标的人本导向与适应性、学科交叉与评测方法的综合化三个方面的研究趋势。

1990-2019年中国痛风疾病负担趋势及未来十年预测研究

背景痛风是常见的炎症性关节炎之一,对人们的健康造成很大的危害,但目前针对我国痛风疾病负担趋势分析与预测的相关研究有限。目的分析1990—2019年中国痛风疾病负担的变化趋势,并预测未来10年痛风的标化伤残调整寿命年(DALYs)率、标化发病率和标化患病率。方法提取全球疾病负担研究(GBD)2019有关中国痛风DALYs、发病情况和患病情况等疾病负担指标,采用Joinpoint回归模型计算标化DALYs率、标化发病率和标化患病率的年度变化百分比(APC)和平均年度变化百分比(AAPC),采用自回归移动平均模型(ARIMA模型)对2020—2029年的标化DALYs率、标化发病率和标化患病率进行预测。结果1990—2019年,中国痛风DALYs从187436人年增至510485人年,增长了172.35%,发病人数从1181969例增至3041329例,增长了157.31%,患病人数从5864143例增至16161325例,增长了175.60%(对应的标化率分别增长了28.45%、25.92%和28.63%)。Joinpoint回归结果显示,1990—2019年,标化DALYs率、标化发病率、标化患病率整体呈上升趋势(AAPC分别为0.9%、0.8%、0.9%,P<0.05)。痛风疾病负担具有明显的性别和年龄差异,男性疾病负担高于女性,标化DALYs率、标化发病率和标化患病率男女性别比范围分别为3.23~3.51、3.14~3.40和3.17~3.42。女性各指标年龄高峰总体比男性延后,女性在45岁之后疾病负担开始加重,男女性疾病负担均在90岁之后再次增加。ARIMA模型结果显示,预计到2029年,因痛风造成的标化DALYs率和标化发病率分别下降0.33%和0.45%,标化患病率上升0.71%。结论1990—2019年中国痛风疾病负担增长趋势明显,存在明显的性别和年龄差异,且出现年轻化趋势。预计到2029年,因痛风造成的标化患病率略有上升。

1991—2021年我国孕产妇死亡率变化情况分析

目的:分析1991—2021年我国孕产妇死亡率及其变化趋势,为制定妇幼健康有关的政策提供科学依据。方法:通过《中国卫生统计年鉴》收集1991—2021年我国孕产妇死亡数据,运用JoinPoint模型,采用平均年度变化百分比(AAPC)和年度变化百分比(APC)分析孕产妇死亡率变化趋势。结果:1991—2021年我国孕产妇死亡率整体呈下降趋势,AAPC为-5.00%,其中1991—2005年APC为-3.71%,2005—2013年APC为-8.16%,2013—2021年APC为-4.05%。1991—2021年我国城市孕产妇死亡率整体呈下降趋势,AAPC为-3.90%,30年间变化趋势出现2个拐点,其中1991—2002年APC为-5.17%,2002—2010年APC为0.70%,2010—2021年APC为-5.82%;1991—2021年我国农村孕产妇死亡率整体呈下降趋势,AAPC为-5.60%,30年间变化趋势出现2个拐点,其中1991—2004年APC为-3.55%,2004—2011年APC为-11.26%,2011—2021年APC为-4.14%。孕产妇主要死亡疾病为产科出血、妊娠期高血压疾病、心脏病、羊水栓塞、产褥感染和肝病。结论:1991—2021年我国孕产妇死亡率整体呈下降趋势,2005—2013年下降幅度较大,农村孕产妇死亡率下降幅度大于城市。产科出血、妊娠期高血压疾病、心脏病、羊水栓塞仍是产科主要死亡疾病,应进一步加强政策支持并优化多学科、全孕期精细管理,以保障孕产妇安全。