汇川H2U系列PLC之间RS-485通信的实现     

尚丽  叶国平 《苏州市职业大学学报》2020,(2):15-21

主要研究了汇川公司H2U可编程控制器(PLC)的通信技术,实现了两个H2U系列PLC之间基于RS-485的通信,并详细介绍了PLC之间通信的硬件连接方式、通信串口参数配置、触摸屏画面的设计以及程序实现。所讨论的方法已在采用H2U PLC及辅助设备组建的"运动控制系统"课程的教学实验平台上进行了验证,可以拓展应用于多台H2U PLC之间以及其他设备与H2U PLC之间的RS-485通信实现,对工程应用具有一定的借鉴意义。  相似文献   

Innovative approaches towards an economic fusion reactor     

Houyang Guo  Francis Y C Thio  Michl W Binderbauer  Richard J Buttery  Thomas R Jarboe  Rajesh Maingi  John S Sarff  Peter C Stangeby  Derek A Sutherland  Mickey R Wade  Michael C Zarnstorff 《国家科学评论(英文版)》2020,7(2):245

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Exertional heat illness risk factors and physiological responses of youth football players     

Susan W. Yeargin  John J. Dickinson  Dawn M. Emerson  Jessica Koller  Toni M. Torres-McGehee  Zachary Y. Kerr 《运动与健康科学(英文)》2021,10(1):91

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石膏/蚯蚓粪肥对赤泥团聚体结构稳定性的影响     

王琼丽  叶羽真  薛生国  江钧  朱锋  田桃 《中国科学院大学学报》2019,36(4):530-536

赤泥是氧化铝工业生产过程中排放的高碱性固体废弃物，迄今尚无经济有效的处置方法。以华中地区某堆场赤泥为研究对象，通过土培实验研究改良剂（石膏、蚯蚓粪肥、石膏+蚯蚓粪肥）对赤泥团聚体稳定性的影响。结果表明：石膏的添加能显著降低赤泥pH，而蚯蚓粪肥能显著增加赤泥有机碳含量。土培60 d时，石膏添加后赤泥pH由10.54降到8.75，蚯蚓粪肥添加后赤泥有机碳含量由3.54 g·kg^-1增加至14.31 g·kg^-1。土培180 d时，石膏、蚯蚓粪肥、石膏+蚯蚓粪肥添加后赤泥水稳性团聚体含量由12.04%分别增加到23.49%、29.24%、33.94%；团聚体平均重量直径由0.15 mm分别增加到0.26、0.30、0.34 mm；可蚀性因子由0.36分别降低到0.31、0.30、0.29。石膏和蚯蚓粪肥的添加促进水稳性团聚体形成，提高赤泥团聚体稳定性。基质改良对赤泥团聚体稳定性的影响效果依次为：石膏+蚯蚓粪肥 > 蚯蚓粪肥 > 石膏。研究结果对赤泥土壤化处置和规模化消纳研究有科学参考意义。  相似文献   

日本泛在学习研究:SCROLL系统的应用及启示     

叶正茂  刘华锦 《成人教育》2021,41(7):83-89

日本在泛在学习项目研究中创建了收集、整理、使用学习日志进行学习的开放平台(SCROLL系统).整体看,SCROLL系统共分为ULL recorder、ULL finder、ULL reminder、ULL navigator四部分,各部分具不同功能.集合多种学习功能的SCROLL系统具有较为广泛的适应性,为泛在学习在我国的发展提供了三方面的启示:互联网形态的转变将使传统在线教育面临极大的挑战;非正式学习将成为未来远程教育的重要形式;建设开放性的泛在学习平台以适应互联网的未来发展.  相似文献   

The social construction of human categories     

Tsou  Jonathan Y. 《Metascience》2021,30(1):115-118

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区域体育产业发展与健康中国建设耦合协调度研究——以我国东部地区11个省市为例     

叶宋忠 《武汉体育学院学报》2020,54(5):31-40

为探讨区域体育产业发展与健康中国建设耦合协调度及未来前景,在分析体育产业与健康中国耦合作用机理的基础上,构建体育产业与健康中国耦合协调发展评价体系,运用熵值法、耦合协调模型和修正GM(1.1)预测法对我国东部地区11省市2013—2017年两大系统耦合协调关系进行实证分析,并预测未来10年两大系统的耦合协调关系。研究发现(1)区域体育产业发展与健康中国建设之间存在明显的相互影响、相互作用关系,耦合协调发展特征显著。(2)东部地区11省市两大系统发展水平总体呈上升态势,且二者具有较高的关联性;体育产业系统发展水平比健康中国系统波动性更强,体育产业成为缩小区域发展差异的有效路径依赖;体育产业发展对健康中国建设的驱动作用较弱,而健康中国建设对体育产业发展促进作用较大。(3)东部地区11省市两大系统耦合协调性在逐年稳步上升,但演进与提升速度较缓慢,协调关系始终处在勉强协调阶段,且耦合协调度存在较大的空间差异,从北向南的空间格局大体上呈现“高—较高—高—较高—高—低”,预测结果显示未来10年耦合协调水平演进与提升速度明显加快,但仍存在显著的空间差异。并提出建议,以期服务实践。  相似文献   

Classification Consistency and Accuracy With Atypical Score Distributions     

Stella Y. Kim  Won-Chan Lee 《Journal of Educational Measurement》2020,57(2):286-310

The current study aims to evaluate the performance of three non-IRT procedures (i.e., normal approximation, Livingston-Lewis, and compound multinomial) for estimating classification indices when the observed score distribution shows atypical patterns: (a) bimodality, (b) structural (i.e., systematic) bumpiness, or (c) structural zeros (i.e., no frequencies). Under a bimodal distribution, the normal approximation procedure produced substantially large bias. For a distribution with structural bumpiness, the compound multinomial procedure tended to introduce larger bias. Under a distribution with structural zeroes, the relative performance of selected estimation procedures depended on cut score location and the sample-size conditions. In general, the differences in estimation errors among the three procedures were not substantially large.  相似文献   

Factors associated with concussion-symptom knowledge and attitudes toward concussion care seeking in a national survey of parents of middle-school children in the US     

Zachary Y. Kerr  Aliza K. Nedimyer  Melissa C. Kay  Avinash Chandran  Paula Gildner  K. Hunter Byrd  Juliet K. Haarbauer-Krupa  Johna K. Register-Mihalik 《运动与健康科学(英文)》2021,10(2):113

BackgroundDeveloping appropriate concussion prevention and management paradigms in middle school (MS) settings requires understanding parents’ general levels of concussion-related knowledge and attitudes. This study examined factors associated with concussion-symptom knowledge and care-seeking attitudes among parents of MS children (aged 10–15 years).MethodsA panel of 1224 randomly selected U.S. residents, aged ≥ 18 years and identifying as parents of MS children, completed an online questionnaire capturing parental and child characteristics. The parents’ concussion-symptom knowledge was measured using 25 questions, with possible answers being “yes”, “maybe”, and “no”. Correct answers earned 2 points, “maybe” answers earned 1 point, and incorrect answers earned 0 point (range: 0–50; higher scores = better knowledge). Concussion care-seeking attitudes were also collected using five 7-point scale items (range: 5–35; higher scores = more positive attitudes). Multivariable ordinal logistic regression models identified predictors of higher scores. Models met proportional odds assumptions. Adjusted odds ratios (aORs) with 95% confidence intervals (95%CIs) (excluding 1.00) were deemed statistically significant.ResultsMedian scores were 39 (interquartile range: 32–44) for symptom knowledge and 32 (interquartile range: 28–35) for care-seeking attitude. In multivariable models, odds of better symptom knowledge were higher in women vs. men (aOR = 2.28; 95%CI: 1.71–3.05), white/non-Hispanics vs. other racial or ethnic groups (aOR = 1.88; 95%CI: 1.42–2.49), higher parental age (10-year-increase aOR = 1.47; 95%CI: 1.26–1.71), and greater competitiveness (10%-scale-increase aOR = 1.24; 95%CI: 1.13–1.36). Odds of more positive care-seeking attitudes were higher in white/non-Hispanics vs. other racial or ethnic groups (aOR = 1.45; 95%CI: 1.06–1.99) and in older parental age (10-year-increase aOR = 1.24; 95%CI: 1.05–1.47).ConclusionCharacteristics of middle school children''s parents (e.g., sex, race or ethnicity, age) are associated with their concussion-symptom knowledge and care-seeking attitudes. Parents’ variations in concussion knowledge and attitudes warrant tailored concussion education and prevention.  相似文献   

Difference score reliabilities within the RIAS-2 and WISC-V     

Ryan L. Farmer  Samuel Y. Kim 《Psychology in the schools》2020,57(8):1273-1288

Many prominent intelligence tests (e.g., Wechsler Intelligence Scale for Children, Fifth Edition [WISC-V] and Reynolds Intellectual Abilities Scale, Second Edition [RIAS-2]) offer methods for computing subtest- and composite-level difference scores. This study uses data provided in the technical manual of the WISC-V and RIAS-2 to calculate reliability coefficients for difference scores. Subtest-level difference score reliabilities range from 0.59 to 0.99 for the RIAS-2 and from 0.53 to 0.87 for the WISC-V. Composite-level difference score reliabilities generally range from 0.23 to 0.95 for the RIAS-2 and from 0.36 to 0.87 for the WISC-V. Emphasis is placed on comparisons recommended by test publishers and a discussion of minimum requirements for interpretation of differences scores is provided.  相似文献