scholarly journals Fig 9. Effect of installation distance of shakers on weight on bit and accelerations of the drill-string. A. Change of weight on bit in the bottom hole over time. B. Maximum acceleration along the drill-string. C. Root mean square acceleration along the dr v1 (protocols.io.kfactie)

protocols.io ◽  
2017 ◽  
Author(s):  
Peng Wang ◽  
Hongjian Ni ◽  
Ruihe Wang
Keyword(s):  
Root Mean Square ◽  
Drill String ◽  
Mean Square ◽  
Maximum Acceleration ◽  
Bottom Hole ◽  
Weight On Bit ◽  
Over Time

scholarly journals Driving Comfort Evaluation for Manhole Covers and Pavement around Manholes

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Quanman Zhao ◽  
Zhigang Li ◽  
Wenjun Hu ◽  
Xianguang Meng ◽  
Hui Zhang
Keyword(s):  
Root Mean Square ◽  
Influencing Factors ◽  
Influence Factors ◽  
Mean Square ◽  
Height Difference ◽  
Maximum Acceleration ◽  
Driving Speed ◽  
Longitudinal Slope ◽  
Variation Characteristics ◽  
Pavement Damage

In order to study the driving comfort and influencing factors when vehicles pass over manholes and pavement around manholes on an urban road, the deformation and vibration of the manhole cover were considered, a multidegree of freedom vibration model of the human-vehicle-manhole cover was established, and the variation characteristics of driving acceleration was analyzed. The root mean square of weighted acceleration was taken as the basic index, and driving comfort was evaluated based on ISO 2631-1-1997 standard. After that, 9 influencing factors were analyzed, such as driving speed, subsidence of manhole, manhole cover stiffness, and longitudinal slope. Then, grey correlation entropy analysis was used to evaluate the influencing factors, and the main factors were determined. The results showed that the maximum acceleration was 3.6 m/s2 when a vehicle was passing over a manhole cover under the basic parameters. At the same time, the root mean square of weighted acceleration was 0.975 m/s2 and driving comfort degree was “uncomfortable.” Driving direction and vibration of the manhole cover had little influence on driving comfort, while the remaining influencing factors had significant influence on that. The ranking of key influence factors on driving comfort was longitudinal slope, driving speed, height difference caused by pavement damage, height difference caused by manhole cover subsidence, tire stiffness, manhole stiffness, and tire damping. Therefore, in order to ensure driving comfort and safety, damage to pavement around manholes and manhole cover subsidence should be repaired in a timely manner.

scholarly journals Examination of the Factor Structure of a Global Cognitive Function Battery across Race and Time

2015 ◽  
Vol 22 (1) ◽  
pp. 66-75 ◽  
Author(s):  
Lisa L. Barnes ◽  
Futoshi Yumoto ◽  
Ana Capuano ◽  
Robert S. Wilson ◽  
David A. Bennett ◽  
...  
Keyword(s):  
Cognitive Function ◽  
African Americans ◽  
Root Mean Square ◽  
Likelihood Estimation ◽  
Cognitive Test ◽  
Mean Square ◽  
Confirmatory Factor Analyses ◽  
The Life Course ◽  
Fit Index ◽  
Over Time

AbstractOlder African Americans tend to perform more poorly on cognitive function tests than older Whites. One possible explanation for their poorer performance is that the tests used to assess cognition may not reflect the same construct in African Americans and Whites. Therefore, we tested measurement invariance, by race and over time, of a structured 18-test cognitive battery used in three epidemiologic cohort studies of diverse older adults. Multi-group confirmatory factor analyses were carried out with full-information maximum likelihood estimation in all models to capture as much information as was present in the observed data. Four different aspects of the data were fit to each model: comparative fit index (CFI), standardized root mean square residuals (SRMR), root mean square error of approximation (RMSEA), and model $$\chi ^{2} $$ . We found that the most constrained model fit the data well (CFI=0.950; SRMR=0.051; RMSEA=0.057 (90% confidence interval: 0.056, 0.059); the model $$\chi ^{2} $$ =4600.68 on 862 df), supporting the characterization of this model of cognitive test scores as invariant over time and racial group. These results support the conclusion that the cognitive test battery used in the three studies is invariant across race and time and can be used to assess cognition among African Americans and Whites in longitudinal studies. Furthermore, the lower performance of African Americans on these tests is not due to bias in the tests themselves but rather likely reflect differences in social and environmental experiences over the life course. (JINS, 2016, 22, 66–75)

The Relationship of Root Mean Square Value of Electromyography and Isometric Torque of Quadriceps in Normal Subjects

2016 ◽  
Vol 26 (1) ◽  
pp. 58
Author(s):  
Qiurong XIE ◽  
Zheng JIANG ◽  
Qinglu LUO ◽  
Jie LIANG ◽  
Xiaoling WANG ◽  
...  
Keyword(s):  
Root Mean Square ◽  
Normal Subjects ◽  
Mean Square ◽  
Isometric Torque ◽  
Relationship Of ◽  
The Relationship

scholarly journals Estimation of Apple Flowering Frost Loss for Fruit Yield Based on Gridded Meteorological and Remote Sensing Data in Luochuan, Shaanxi Province, China

2021 ◽  
Vol 13 (9) ◽  
pp. 1630
Author(s):  
Yaohui Zhu ◽  
Guijun Yang ◽  
Hao Yang ◽  
Fa Zhao ◽  
Shaoyu Han ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Root Mean Square Error ◽  
Mean Square Error ◽  
Root Mean Square ◽  
Minimum Temperature ◽  
Price Regulation ◽  
Flowering Period ◽  
Mean Square ◽  
Prevention Measures ◽  
Agricultural Insurance

With the increase in the frequency of extreme weather events in recent years, apple growing areas in the Loess Plateau frequently encounter frost during flowering. Accurately assessing the frost loss in orchards during the flowering period is of great significance for optimizing disaster prevention measures, market apple price regulation, agricultural insurance, and government subsidy programs. The previous research on orchard frost disasters is mainly focused on early risk warning. Therefore, to effectively quantify orchard frost loss, this paper proposes a frost loss assessment model constructed using meteorological and remote sensing information and applies this model to the regional-scale assessment of orchard fruit loss after frost. As an example, this article examines a frost event that occurred during the apple flowering period in Luochuan County, Northwestern China, on 17 April 2020. A multivariable linear regression (MLR) model was constructed based on the orchard planting years, the number of flowering days, and the chill accumulation before frost, as well as the minimum temperature and daily temperature difference on the day of frost. Then, the model simulation accuracy was verified using the leave-one-out cross-validation (LOOCV) method, and the coefficient of determination (R2), the root mean square error (RMSE), and the normalized root mean square error (NRMSE) were 0.69, 18.76%, and 18.76%, respectively. Additionally, the extended Fourier amplitude sensitivity test (EFAST) method was used for the sensitivity analysis of the model parameters. The results show that the simulated apple orchard fruit number reduction ratio is highly sensitive to the minimum temperature on the day of frost, and the chill accumulation and planting years before the frost, with sensitivity values of ≥0.74, ≥0.25, and ≥0.15, respectively. This research can not only assist governments in optimizing traditional orchard frost prevention measures and market price regulation but can also provide a reference for agricultural insurance companies to formulate plans for compensation after frost.

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