Undisturbed pit sampling of tropical red clay soils

AbstractThe tropical red clay soils, formed by the Quaternary weathering of volcanic deposits (and other rock types) in tropical and subtropical environments, have a very open structure and consequent high voids ratio. These soils are particularly sensitive to disturbance during sampling and subsequent transportation and extrusion of the samples. This technical note describes a simple method for obtaining high quality, undisturbed samples from pits in a way that does not require extrusion or trimming of the sample in the laboratory prior to triaxial testing, and only minimal preparation prior to oedometer testing.

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A Simple Method to Avoid Brain Shift during Neuronavigation: Technical Note

Arquivos Brasileiros de Neurocirurgia Brazilian Neurosurgery ◽

10.1055/s-0040-1716560 ◽

2020 ◽

Author(s):

Jair Leopoldo Raso

Keyword(s):

Dura Mater ◽

Brain Area ◽

Conventional Technique ◽

Technical Note ◽

Cortical Surface ◽

Brain Shift ◽

Simple Method ◽

Cortex Area ◽

Neuronavigation System ◽

The Brain

Abstract Introduction The precise identification of anatomical structures and lesions in the brain is the main objective of neuronavigation systems. Brain shift, displacement of the brain after opening the cisterns and draining cerebrospinal fluid, is one of the limitations of such systems. Objective To describe a simple method to avoid brain shift in craniotomies for subcortical lesions. Method We used the surgical technique hereby described in five patients with subcortical neoplasms. We performed the neuronavigation-guided craniotomies with the conventional technique. After opening the dura and exposing the cortical surface, we placed two or three arachnoid anchoring sutures to the dura mater, close to the edges of the exposed cortical surface. We placed these anchoring sutures under microscopy, using a 6–0 mononylon wire. With this technique, the cortex surface was kept close to the dura mater, minimizing its displacement during the approach to the subcortical lesion. In these five cases we operated, the cortical surface remained close to the dura, anchored by the arachnoid sutures. All the lesions were located with a good correlation between the handpiece tip inserted in the desired brain area and the display on the navigation system. Conclusion Arachnoid anchoring sutures to the dura mater on the edges of the cortex area exposed by craniotomy constitute a simple method to minimize brain displacement (brain-shift) in craniotomies for subcortical injuries, optimizing the use of the neuronavigation system.

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New outlooks on bunched beam instabilities in particle accelerators. A proposal for a simple method to release a potential self-consistent high quality beam

Proceedings of International Conference on Particle Accelerators ◽

10.1109/pac.1993.309766 ◽

2002 ◽

Cited By ~ 1

Author(s):

M. Bergher

Keyword(s):

Particle Accelerators ◽

High Quality ◽

Simple Method ◽

Self Consistent ◽

Beam Instabilities

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Consolidation parameters conceptualization using regression analysis and genetic programming for Addis Ababa’s red clay soils

Modeling Earth Systems and Environment ◽

10.1007/s40808-021-01127-2 ◽

2021 ◽

Author(s):

Nigist Abera Gashaw ◽

Eleyas Assefa ◽

Costas Sachpazis

Keyword(s):

Regression Analysis ◽

Genetic Programming ◽

Clay Soils ◽

Red Clay ◽

Consolidation Parameters

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Simple Method of Rock Pore Structure Determination Presented with the Most Common Rock Types Quarried in Slovakia

Springer Series in Geomechanics and Geoengineering - Energy Geotechnics ◽

10.1007/978-3-319-99670-7_38 ◽

2018 ◽

pp. 299-306

Author(s):

Martin Ondrášik ◽

Jana Frankovská ◽

Miloslav Kopecký ◽

Martin Brček

Keyword(s):

Pore Structure ◽

Structure Determination ◽

Simple Method ◽

Rock Types

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Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

Computational Intelligence and Neuroscience ◽

10.1155/2018/6103726 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14

Author(s):

José Carlos Ortiz-Bayliss ◽

Ivan Amaya ◽

Santiago Enrique Conant-Pablos ◽

Hugo Terashima-Marín

Keyword(s):

Constraint Satisfaction ◽

Constraint Satisfaction Problems ◽

Search Cost ◽

High Quality ◽

Simple Method ◽

Variable Ordering ◽

It Performance ◽

The Cost ◽

The Impact ◽

Variable Ordering Heuristics

When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

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