Research and Development Trend of Shape Control for Cold Rolling Strip

Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain can help to seek new breakthrough directions. In the past 10 years, researches and applications of shape control models, shape control means, shape detection technology, and shape con- trol system have achieved significant progress. In the aspect of shape control models, the researches in the past improve the accuracy, speed and robustness of the models. The intelligentization of shape control models should be strengthened in the future. In the aspect of the shape control means, the researches in the past focus on the roll opti- mization, mill type selection, process optimization, local strip shape control, edge drop control, and so on. In the future, more attention should be paid to the coordination control of both strip shape and other quality indexes, and the refinement of control objective should be strengthened. In the aspects of shape detection technology and shape control system, some new types of shape detection meters and shape control systems are developed and have successfully indus- trial applications. In the future, the standardization of shape detection technology and shape control system should be promoted to solve the problem of compatibility. In general,the four expected development trends of shape control for cold roiling strip in the future are intelligentization, coordi- nation, refinement, and standardization. The proposed research provides new breakthrough directions for improv- ing shape quality.

Special Issue on New Trends in Theory and Applications of Complex Control Systems

Complexity is one of the leading features of modem control systems. It is caused by the complex properties of controlled plants and the varied requirements in controller designs. In dealing with the control problems with complexity, in the past two decades, a lot of papers have been published that reported fruitful results on different theoretical backgrounds and with different methodologies, such as differential geometry-based design methods, hybrid system theory, switching control, neural network-based intelligent control, etc.

DESERTIFICATION IN CHINA: STATUS, TRENDS, AND STRATEGIES

Based on defition of desertification in Intematonal Convention toCombat Desertfication. and on China's situation, desenification is found notonly In and and senuand ropons but also in huAnd and subhunud ropons. InChina the desertified land area has already reached 1,1 17,000kin2, or 11.6percen of China's total land area. Of which 33.2 percent is caused by winderosion, 33.8 percen by water erosion and 33.0 percen by physical andchemical actions. Besides- another 535,000 kin2 of land is susceptible to wind erosion, 875,000 km2 to water erosion and 173,000 km2 to saliruzation.Land desertification in China is the result Of over growth of populahon and irrational human aCtivities, such as abuse of water res ou rces, overculti vati on'overgrazlng. deforestaion, vopation destruCtion and envirormental polluton caused by industry and nurung under fragile ecological conditions.In recat decades, reverse tronds have occurred in mpons under proper conrol.However. on the Whole it has beenexpanding. For instance, sandy desertification develops at an annual rate of 1.39 percen in agropastoral ropons in Northem China. This paper is supposed to evaluate the curren conrol measures and practices of desertification- in ligh of the distributon characteristics and developmedl trend of land desertification in China.

Spatial and temporal variations and controlling factors of potential evapotranspiration in China:1956-2000

Based on the climatic data of 580 stations in China during 1956 and 2000, potential evapotranspiration are calculated using the Penman-Monteith Method recommended by FAO. The spatial and temporal distributions of the potential evapotranspiration over China and the temporal trends of the regional means for 10 major river basins and whole China are analyzed. Through a partial correlation analysis, the major climate factors which affect the temporal change of the potential evapotranspiration are analyzed. Major results are drawn as follows： 1） The seasonal and annual potential evapotranspiration for China as a whole and for most basins show decline tendencies during the past 45 years; for the Songhua River Basin there appears a slightly increasing trend. 2） Consequently, the annual potential evapotranspirations averaged over 1980-2000 are lower than those for the first water resources assessment （1956-1979） in most parts of China. Exceptions are found in some areas of Shandong Peninsula, western and middle basins of the rivers in Southwest China, Ningxia Hui Autonomous Region as well as the source regions of the Yangtze and Yellow rivers, which may have brought about disadvantages to the exploration and utilization of water resources. 3） Generally, sunshine duration, wind speed and relative humidity have greater impact on the potential evapotranspiration than temperature. Decline tendencies of sunshine duration and/or wind speed in the same period appear to be the major causes for the negative trend of the potential evapotranspiration in most areas.

病毒传播变异与人群交叉活动的相互影响及扩散模型研究

针对当前人际传染病毒高发态势,综合考虑病毒传播变异的随机特征和人群交叉活动之间的相互影响,提出并设计了多智能体模拟仿真推演模型。将病毒个体的外在致病性、传染性特征和人群个体的外在活动、免疫特征进行量化,将病毒个体与人群个体之间的相互依存及对抗过程进行建模,通过模型推演大量病毒个体和人群个体的发展趋势和统计特征。通过实验分析揭示了单个病毒变异方向的随机性不影响病毒群体变异发展方向的确定性:即病毒群体的致病性强度不断降低直到稳定在低值区间内,病毒群体的传染性强度不断升高,直到稳定在较高的数值区间内。给出了影响病毒传播变异过程的关键外在参数,可为高致病性病毒早期防控提供政策建议。

Automated Identification of Basic Control Charts Patterns Using Neural Networks

The identification of control chart patterns is very important in statistical process control. Control chart patterns are categorized as natural and unnatural. The presence of unnatural patterns means that a process is out of statistical control and there are assignable causes for process variation that should be investigated. This paper proposes an artificial neural network algorithm to identify the three basic control chart patterns;natural, shift, and trend. This identification is in addition to the traditional statistical detection of runs in data, since runs are one of the out of control situations. It is assumed that a process starts as a natural pattern and then may undergo only one out of control pattern at a time. The performance of the proposed algorithm was evaluated by measuring the probability of success in identifying the three basic patterns accurately, and comparing these results with previous research work. The comparison showed that the proposed algorithm realized better identification than others.

海洋悬浮物浓度的长期演变特征及机制

受气候变化和人类活动的影响,21世纪以来全球海洋的悬浮物浓度发生了显著变化。悬浮物浓度的剧烈变化不可避免地对海洋生态环境、地貌演化和生物地球化学循环产生重大影响。随着气候变化对人类活动的环境影响研究的深入,以及卫星遥感数据的不断积累,悬浮物浓度的长期变化趋势及其机制已成为地球科学研究的热点。本文概括性地总结了海洋悬浮物浓度长期变化的国内外研究进展,指出了中国近海相关研究的不足之处,并对未来发展方向作出了展望。

高校思政教育数智化发展的趋势、回应与把控

数智技术的内涵和特征不仅与高校思政教育的原则、目标、方法高度契合,而且对于自主意识和可塑性较高的大学生而言,更能利用数据和算法创造或还原虚拟现实的教育场景、虚实融合的数字人设、亦幻亦真的交互体验和超越内禀属性的主观存在,进而提高思政教育质效。梳理数智技术的演进历程与特征,深入把握数智化发展的复合命体演进趋势、“超级语径”交互趋势和虚拟现实趋势,需要锻铸多模态数据融合的思政教育“新命体”,培育面向未来教育的教师“数商”,强化应对数字化转型的“关键能力”。通过把控、优化对高校思政教育“教学原料”“大数据情境”“未来既视感”的算法拓展和算力支撑,保持技术创新与高校思政教育发展的精准契合,从而更好地实现高校思政教育立德树人的根本任务。

某综合医院皮肤性病科门诊梅毒感染分析

目的统计2017年1月至2022年12月滨州医学院附属医院皮肤性病科门诊就诊患者梅毒感染情况,分析其感染率及流行趋势,为制定梅毒防控措施提供依据。方法收集自愿进行梅毒检测患者的一般资料、梅毒螺旋体颗粒凝集试验(TPPA)和快速血浆反应素试验(RPR)检测数据,并进行统计学处理和分析。结果2017至2022年,该院皮肤性病科门诊累计筛查患者6290例,阳性感染者3198例,年筛查人群阳性感染率分别为54.58%、53.19%、52.35%、49.79%、46.21%、45.89%。现症感染者1321例(21.00%),年筛查人群现症感染率分别为23.21%、21.84%、20.99%、19.72%、19.53%、19.45%。感染高发年龄主要集中在21~40岁。感染人群中女性占比高于男性(P<0.05),性别比例为1:0.89。2017至2019年女性占比分别为51.92%、53.19%、58.24%,呈逐年上升趋势,而2020至2022年女性占比明显下降,分别为50.32%、50.81%、50.27%。结论梅毒感染率整体呈缓慢降低趋势,21~40岁为梅毒感染高发年龄段,女性感染率高于男性,而40岁以后女性则低于男性。因此,应加大对梅毒等性传播疾病的监测力度。

国内集团管控研究的热点问题及演进趋势

集团管控体系作为集团企业持续发展的基石,是企业效益和竞争力的动力来源.以2002—2023年CNKI数据库收录的与国内集团管控相关的期刊论文为样本,利用信息可视化软件CiteSpace分析有关集团管控的研究主题,梳理近二十年的研究和不同阶段研究的特点,研究发现国内集团管控研究群体正处在高速发展时期,集团管控研究机构主要集中在大型国央企、研究院所和高校,研究热点集中于集团治理结构、集团公司战略管理、集团公司内部控制、集团公司管控模式与机制、集团公司创新管控五个方面,研究视角趋向多元化,并呈现多学科交叉的趋势.在新形势下,企业集团的数字化管控和国际化管控是值得关注的方向.

管制扇区运行稳度K-means聚类与分析

为更好地分析管制扇区运行存在的稳定亚安全状态和不稳定亚安全状态,使用K-means算法划分超容比(ECR)、滞留度和飞行姿态混合比3个管制扇区运行稳度评价指标聚类,确定管制扇区运行稳度最佳等级划分;聚类分析单一指标,获得各等级对应的指标阈值,结合熵权法计算的指标权重,遵循隶属度最大原则,获取各时间段的管制扇区运行稳度等级,构建管制扇区运行稳度综合评价模型;选取厦门01号扇区的实际飞行数据,从稳度和趋度2个角度更加全面地分析管制扇区运行态势。结果表明:管制扇区运行稳度等级划分为3类时效果最好;稳度受空中交通流和管制状况的影响会随时间而变化,尤其7:30—9:15和20:00—21:00这2个时间段管制扇区运行稳度的变化最为明显,需引起管制员高度重视,提高空域运行安全。

上海市某区居民2018——2021年传染病防治素养变化趋势

目的 分析青浦区居民传染病防治素养的变化趋势及影响因素,为进一步提高当地居民的传染病防治素养提供指导。方法 采用多阶段简单随机抽样方法,对2018—2021年青浦区15~69岁的常住人口8 129人进行问卷调查。结果 2018—2021年青浦区居民传染病防治素养水平分别为17.7%、19.8%、38.1%和24.5%,总体呈增长趋势,但在2021年出现波动。Logistic回归分析结果显示,年龄、职业和文化程度是青浦区居民传染病防治素养水平的影响因素(P<0.05)。结论 青浦区居民2018—2021年的传染病防治素养总体呈上升趋势,但存在一定波动;年龄、文化程度和职业是传染病防治素养的影响因素。

流域面源污染研究进展与展望

面源污染已成为影响流域水环境和水安全的重要来源,是当前国内外学者关注的热点之一,同时也是最具挑战性的研究领域之一。科学高效地治理面源污染问题已经纳入国家战略计划。因此,在新形势和政策背景下如何推进面源污染研究工作,以保障流域水环境可持续发展已成为紧迫任务。本文较为全面地回顾和总结了我国面源污染研究现状,归纳了主要研究方法和典型治理措施,并基于研究中存在的主要问题,结合我国水污染治理现状给出相应建议,指出未来发展趋势。本文可为面源污染的全过程监管、评估及治理提供重要参考,有助于完善我国水污染治理体系。

Evaluation matrix with the speed feature based on double inspiriting control lines

Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to remedy this deficiency. Firstly, the change speed state （CSS） of the evaluated objects is analyzed based on double inspiriting control lines （DICLs）, and a matrix of the CSS is constructed. Then, 72 elements in the matrix are analyzed, and formulas describing each CSS are given. The efficiency of the proposed evaluation matrix is proved when the CSS merges with the change speed trend （CST） in the dynamic comprehensive evaluation. Finally, a computing example shows that the proposed evaluation matrix is feasible in the dynamic comprehensive evaluation with the speed feature.

基于二项分布的统计过程控制方法在血液质量控制中的应用研究

目的通过引入统计过程控制(SPC)方法,分析去白细胞悬浮红细胞的质量控制项目,以期在血液质量控制数据的有效应用方面取得进展,并为血液质量的持续改进提供循证依据。方法自2020—2022年,收集了重庆地区6家血站的去白细胞悬浮红细胞质量控制项目检测数据。利用Minitab软件进行统计过程控制分析,绘制p控制图,计算各质控项目的不符合率及其95%置信区间,以及过程能力指数(Z值)。结果根据《全血及成分血质量要求》对去白细胞悬浮红细胞的质量控制项目进行评估,得出外观、储存期末溶血率、无菌试验符合率均为100%。然而,容量、血红蛋白含量、血细胞比容、白细胞残留量的符合率未能达到100%,但均≥75%。通过基于二项分布的p控制图,进一步识别了生产过程的受控状态。在总体符合率满足国标要求的情况下,发现容量、血红蛋白含量、血细胞比容、白细胞残留量在不同机构中存在失控点,并呈现出明显的趋势。各质控项目的不符合率虽均小于25%,但在95%置信水平下,B、C、E、F,4家血站的白细胞残留量显示不符合规定(>25%)。通过构建能力评价指标Z值进行计数资料的过程能力分析,结果显示E机构的容量,以及B、C、F机构的血细胞比容和全部6家血站的白细胞残留量Z值均<2,提示存在质量改进的空间。结论基于二项分布的统计过程控制方法,对血液成分质量控制具有较好的应用价值,能够进一步实现对血液采集、制备和储存过程的实时监控和过程改进。

2024年中国经济形势展望与政策建议

2023年前三季度中国GDP同比增长5.2%,经济运行稳定恢复,预计完成年初制定的增速目标无忧。展望2024年,全国人口减少、技术“封锁”、能源价格波动、汇率波动、国际政治和经济形势变化等仍将是影响中国经济发展的重要因素。中国宏观经济运行的自然走势将是供给、需求双恢复的格局,并且供给端恢复程度要快于需求端,但仍低于潜在水平。房地产危机风险、地方政府债务风险、外部经济环境等将成为未来影响中国经济稳定发展的潜在风险点。鉴于此,2024年的政策目标仍需以需求端作为主要发力点,同时对供给端的稳定恢复和市场环境的持续改善提供必要的支持,宏观调控政策以需求供给双扩张的政策取向为主,同时搭配市场环境管理为辅的政策组合。总的看,2024年我国经济面临的机遇大于挑战,有利条件强于不利因素,支撑高质量发展的要素条件不断集聚增多,我们要增强信心和底气。

关于有源电力滤波器的综述分析

电力系统逐渐发展成为以电力电子为基础的电力系统,各种电能质量问题的存在,推动了有源电力滤波器(Active Power Filter,APF)的发展。APF作为综合性电能质量调节器,是一种具备动态谐波抑制和无功补偿功能的新型电力电子装置,其性能优劣与所采用的拓扑结构、电流追踪控制方法等密切相关。为了推广在高压大容量下APF的控制技术,拓宽其应用范围,分类整理了APF拓扑结构,归纳总结了APF的电流跟踪控制技术,将各种控制方法进行了性能对比,并从多个角度阐述了当前所存在的问题,为研究人员提供参考。此外,还简要总结了APF的进一步发展趋势。

铜顶吹熔炼过程中砷元素的走向调控研究

随着铜精矿品位逐渐下降,精矿中的杂质元素越来越多,其中有害元素砷在冶炼过程中很难脱除,且在铜熔炼系统中循环累积,最终影响阴极铜的质量。某冶炼企业铜顶吹熔炼生产实践中,有害砷元素在烟尘中的分配比例为55%~75%,在铜锍相中分配比例为5%~15%,在渣相中分配比例为20%~35%。本文主要对铜顶吹熔炼过程中砷的分布与走向调控手段进行了理论分析,并在实验室条件下探究了熔渣中Fe/SiO_(2)、富氧浓度、铜锍品位、渣中CaO含量等工艺参数对不同产出物中砷分配率的影响规律,获得了砷进入渣相的有效调控措施。优化工艺参数后,As在渣中占比为30%~40%,烟尘中占比为50%~60%,铜锍中占比为10%~20%,解决了铜冶炼过程砷进入硫酸系统形成大量污酸的问题,从而控制各个产品中砷的含量。

准零刚度非线性低频隔振器理论研究及应用

隔振器在各行业中得到广泛应用,传统线性隔离器因其简单、低廉、高可靠性和鲁棒性被广泛应用于工业中,然而由于其仅能够在激励频率大于√2倍固有频率时才能有效抑制振动,故存在静态承载能力和低频隔振性能之间的固有矛盾。近几十年来发展起来的非线性准零刚度(QZS)隔振器可以在保证高承载能力的前提下降低动刚度,从而将隔振频带拓宽到低频区域。从QZS隔振器的构造方法、优化与改进设计和工程应用等方面综述QZS隔振的主要研究进展,总结现有研究的不足,展望未来发展方向,为相关领域的研究人员提供参考。

巡飞弹航迹规划与飞行控制方法发展

巡飞弹是无人机技术与弹药技术结合的产物,可实现战场态势感知、精确打击、信息支援等功能,是未来信息化作战的重要武器之一。介绍巡飞弹的定义组成、分类方法、作战功能、型号发展、战场应用等情况;阐述巡飞弹航迹规划方法的发展现状和未来趋势,包括传统规划方法、智能规划算法和集群规划算法等;对巡飞弹飞行控制的关键技术,包括制导、姿控和导航技术的发展现状和未来趋势进行了介绍,其中的制导技术包括巡飞段跟踪制导、俯冲段末制导和多弹协同制导等;展望了巡飞弹未来的发展方向。