This paper provides an introduction to specifying multilevel models using PROC MIXED. After a brief introduction to the field of multilevel modeling, users are provided with concrete examples of how PROC MIXED can be used to estimate (a) two-level organizational models, (b) two-level growth models, and (c) three-level organizational models. Both random intercept and random intercept and slope m...

A stronger conjecture is that any closed, connected, orientable, irreducible 3-manifold= with in"nite fundamental group has a virtually positive "rst Betti number, i.e.= has a "nite cover which has positive "rst Betti number. Conjecture 0.1 becomes more compelling due to the recent work of Gabai et al. [16]. In fact it follows from [16] (as well as [9, 12, 13, 32]) that if a closed 3-manifold= ...

Small-scale slope modelling was performed to evaluate the failure process of a landslide triggered by artificial rainfall. The model platform 2.3 m long, 1.0 wide, and 0.5 deep used build small-scale models with same geometric conditions but different soil types/materials, including sand two sand-kaolin mixtures angle. hydraulic response under simulated rainfall monitored using volumetric water...

generally, the evaluation and assessment critical condition of rill formation are useful for a better understanding of soil erosion processes. the inherence characteristics of soils, which have much dynamic variations on the hill-slopes and are affected by rill formation, are the soil critical shear stress and soil erodibility factors. this study aims to assess experimental rill incision thresh...

high‑intensity focused ultrasound (hifu) is a novel treatment modality used by scientists and clinicians in the recent decades. this modality has had a great and significant success as a noninvasive surgery technique applicable in tissue ablation therapy and cancer treatment. in this study, radio frequency (rf) ultrasound signals were acquired and registered in three stages of before, during, a...

In this study, nonlocal nonlinear instability and the vibration of a double carbon nanotube (CNT) system have been investigated. The Visco-Pasternak model is used to simulate the elastic medium between nanotubes, on which the effect of the spring, shear and damping of the elastic medium is considered. Both of the CNTs convey a viscose fluid and a uniform longitudinal magnetic field is applied t...