Results 41 to 50 of about 338,284 (271)

Experimental and numerical analyses of the displacements and stiffnesses of a needle roller bearing under different conditions

Scientific Reports
The displacement and stiffness of a roller bearing affect the reliability and remaining life of the roller bearing. In order to establish a method for predicting the displacement and stiffness of a needle roller bearing, experimental and numerical ...
Ran Li, Wenshu Wei, Fengcai Liu, Hao Liu, Jian Ye, Yuehua Lai, Jianfeng Li, Tianze Cao, Haicheng Lu, Wenbo Li   +9 more
doaj   +1 more source

Influence of rockbolt pretension on bolting behaviors by gravel bolting tests

Journal of Rock Mechanics and Geotechnical Engineering
The influence of rockbolt pretension on bolting has not been well addressed, despite its critical importance in drift support systems. In this study, laboratory and numerical simulations of gravel bolting are conducted to investigate the effects of ...
Xiaoqing Wang, Jinfu Lou, Jianzhong Li, Fuqiang Gao, Guiyang Yuan   +4 more
doaj   +1 more source

Variance-Optimal Offline and Streaming Stratified Random Sampling [PDF]

, 2018
Stratified random sampling (SRS) is a fundamental sampling technique that provides accurate estimates for aggregate queries using a small size sample, and has been used widely for approximate query processing.
Nguyen, Trong, Shih, Ming-Hung, Srivastava, Divesh, Tirthapura, Srikanta, Tirthapura, Srikanta, Xu, Bojian   +5 more
core   +3 more sources

Movement Law and Discriminant Method of Key Strata Breakage Based on Microseismic Monitoring

Shock and Vibration, 2019
Because of the unique natural geography, geological structure, and ecological environment, there are serious geological disasters and environmental damage caused by the high‐intensity mining in Western China. It seriously restricts the development of coal resources and the protection of ecological environment.
Yang Li, Tianhong Yang, Weidong Song, Ling Yu   +3 more
openaire   +2 more sources

Adherence to Protocol Recommendations for Children With Wilms Tumour in Two Consecutive Studies in the United Kingdom and Ireland—Does Variation Matter?

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background and Aims Wilms tumour (WT) has excellent event‐free and overall survival (OS). However, small differences exist between countries participating in the same international study. This led us to examine variation in adherence to protocol recommendations as a potential contributing factor.
Suzanne Tugnait, R. Al‐Saadi, A. Lopez‐Cortes, K. Dzhuma, M. Oostveen, J. Brok, S. Irtan, M. Weeks, J. Bate, S. Baker, R. Williams, M. Powis, D. Saunders, O. Olsen, T. Watson, S. Shelmerdine, S. Vaidya, L. Howell, C. Duncan, G. M. Vujanic, C. Stiller, G. P. Balchin, T. Chowdhury, K. Pritchard‐Jones   +23 more
wiley   +1 more source

Experimental and numerical study on valve dynamic impact contact characteristics and fault diagnosis of a reciprocating piston pump

Science Progress
With the increase in power and flow of emulsion pumps, pump valves are more likely to be damaged during long working hours, Therefore, it is important to ensure the reliability of pump valves at all stages.
Ran Li, WenShu Wei, YueHua Lai, HaiCheng Lu, TianZe Cao, Jian Ye, Hao Liu   +6 more
doaj   +1 more source

Movement Boundary Shape of Overburden Strata and Its Influencing Factors

Energies, 2018
Strata movement boundary is not only a parameter for the prediction of overburden strata movement and deformation but also a key index of setting shafts, roadways and protective coal pillars.
Changchun He, Jialin Xu, Fei Wang, Feng Wang   +3 more
doaj   +1 more source

Convex Polytopes and Quasilattices from the Symplectic Viewpoint [PDF]

, 2007
We construct, for each convex polytope, possibly nonrational and nonsimple, a family of compact spaces that are stratified by quasifolds, i.e. each of these spaces is a collection of quasifolds glued together in an suitable way.
D. Shechtman, E. Abe, E. Lerman, E. Prato, F. Battaglia, F. Battaglia, Fiammetta Battaglia, K. Karu, M. Goresky, P. Bressler, R. Penrose, R. Sjamaar, R.M. Robinson, T. Delzant, V. Guillemin   +14 more
core   +2 more sources

Pediatric Oncology Nursing Competencies in Latin America and the Caribbean: A Scoping Review to Inform Practice, Education, and Research

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background Nurses are central to cancer care for children and adolescents, yet no comprehensive synthesis has defined essential core competencies for pediatric oncology nursing (PON) practice internationally, particularly in Latin America and the Caribbean (LAC).
Luís Carlos Lopes‐Júnior, Edmara Bazoni Soares Maia, Soad Fuentes‐Alabí, Courtney E. Sullivan, Monnie Abraham, Mauricio Maza, Liliana Vásquez Ponce, Regina Aparecida Garcia Lima   +7 more
wiley   +1 more source

Three-Dimensional Physical Similarity Simulation of the Deformation and Failure of a Gas Extraction Surface Well in a Mining Area

Advances in Civil Engineering, 2020
Surface well deformation and failure in a mining area are a key issue challenging the surface well gas extraction technique. To provide information for the design of gas extraction surface wells in mining areas, the deformation and failure of surface ...
Junhui Fu, Haitao Sun, Guangcai Wen, Rifu Li   +3 more
doaj   +1 more source