Effect of Smear on Finite Strain Radial Consolidation for Vertical Prefabricated Drain in Compressible Soils

2003 ◽  
Author(s):  
Kuang-Hsiang Chen ◽  
Tzung-Hsun Hsieh ◽  
I.-Fan Lin
Keyword(s):  
Finite Strain ◽  
Soil Layer ◽  
Strain Condition ◽  
Peripheral Smear ◽  
Drain Spacing ◽  
Vertical Strain ◽  
Time Result ◽  
Time Required ◽  
Compressible Soil ◽  
First Time

Radial consolidation equations for vertical prefabricated drain which considers the effects of drain spacing, well resistance, extension of drain above the compressible soil layer, well peripheral smear effect, and differential vertical strain between smear zone and undisturbed zone at finite strain condition are derived. Particularly, the effects of smear as well as differential vertical strain between smear zone and undisturbed zone at finite strain condition are studied for the first time. Result indicating the time required for consolidation is increased by the effect of well peripheral smear. The effect of differential vertical strain can be ignored.

Realistic hardening-to-softening transition effects of metals over the finite strain range up to failure

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Zi-Han Xu ◽  
Lin Zhan ◽  
Si-Yu Wang ◽  
Hui-Feng Xi ◽  
Heng Xiao
Keyword(s):  
Finite Strain ◽  
Plastic Work ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Trial And Error ◽  
Content Type ◽  
Transition Effects ◽  
Iterative Procedures ◽  
First Time ◽  
Hardening And Softening

PurposeA new approach is proposed toward accurately matching any given realistic hardening and softening data from uniaxial tensile test up to failure and moreover, toward bypassing usual tedious implicit trial-and-error iterative procedures in identifying numerous unknown parameters.Design/methodology/approachFinite strain response features of metals with realistic hardening-to-softening transition effects up to eventual failure are studied for the first time based on the self-consistent elastoplastic J2-flow model with the logarithmic stress rate. As contrasted with usual approximate and incomplete treatments merely considering certain particular types of hardening effects such as power type hardening, here a novel and explicit approach is proposed to obtain a complete form of the plastic-work-dependent yield strength over the whole hardening and softening range.FindingsA new multi-axial evolution equation for both hardening and softening effects is established in an explicit form. Complete results for the purpose of model validation and prediction are presented for the finite strain responses of monotonic uniaxial stretching up to failure.Originality/valueNew finite strain elastoplastic equations are established with a new history-dependent variable equivalently in place of the usual plastic work. With these equations, a unified and accurate simulation of both gardening and softening effects up to failure is achieved for the first time in an explicit sense without involving usual tedious implicit trial-and-error iterative procedures.

scholarly journals Principal Component Gradiometer technique for removal of spacecraft-generated disturbances from magnetic field data

2020 ◽  
Author(s):  
Ovidiu Dragoş Constantinescu ◽  
Hans-Ulrich Auster ◽  
Magda Delva ◽  
Olaf Hillenmaier ◽  
Werner Magnes ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Principal Component ◽  
Field Measurements ◽  
Magnetic Field Data ◽  
Service Oriented ◽  
Sensor Configuration ◽  
Time Required ◽  
First Time ◽  
The Magnetic Field

Abstract. In situ measurement of the magnetic field using space borne instruments requires either a magnetically clean platform and/or a very long boom for accommodating magnetometer sensors at a large distance from the spacecraft body. This significantly drives up the costs and time required to build a spacecraft. Here we present an alternative sensor configuration and an algorithm allowing for ulterior removal of the spacecraft generated disturbances from the magnetic field measurements, thus lessening the need for a magnetic cleanliness program and allowing for shorter boom length. The proposed algorithm is applied to the Service Oriented Spacecraft Magnetometer (SOSMAG) onboard the Korean geostationary satellite GeoKompsat-2A (GK2A) which uses for the first time a multi-sensor configuration for onboard data cleaning. The successful elimination of disturbances originating from several sources validates the proposed cleaning technique.

scholarly journals Kinematics and Timing Constraints in a Transpressive Tectonic Regime: The Example of the Posada-Asinara Shear Zone (NE Sardinia, Italy)

Geosciences ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 288
Author(s):  
Rodolfo Carosi ◽  
Alessandro Petroccia ◽  
Salvatore Iaccarino ◽  
Matteo Simonetti ◽  
Antonio Langone ◽  
...  
Keyword(s):  
Shear Zone ◽  
Finite Strain ◽  
Pure Shear ◽  
Deformation Gradient ◽  
Shear Zones ◽  
Temperature Deformation ◽  
Timing Constraints ◽  
Important Variation ◽  
Deformation Phase ◽  
First Time

Detailed geological field mapping, integrated with meso- and microstructural investigations, kinematic of the flow and finite strain analyses, combined with geochronology, are fundamental tools to obtain information on the temperature–deformation–timing path of crystalline rocks and shear zone. The Posada-Asinara shear zone (PASZ) in northern Sardinia (Italy) is a steeply dipping km-thick transpressive shear zone. In the study area, located in the Baronie region (NE Sardinia), the presence of mylonites within the PASZ, affecting high- and medium-grade metamorphic rocks, provides an opportunity to quantify finite strain and kinematic vorticity. The main structures of the study area are controlled by a D2 deformation phase, linked to the PASZ activity, in which the strain is partitioned into folds and shear zone domains. Applying two independent vorticity methods, we detected an important variation in the percentage of pure shear and simple shear along the deformation gradient, that increases from south to north. We constrained, for the first time in this sector, the timing of the transpressive deformation by U–(Th)–Pb analysis on monazite. Results indicate that the shear zone has been active at ~325–300 Ma in a transpressive setting, in agreement with the ages of the other dextral transpressive shear zones in the southern Variscan belt.

Human Factors in Spacelab: Crew Training

1983 ◽  
Vol 27 (7) ◽  
pp. 552-556
Author(s):  
Maria K. Junge
Keyword(s):  
Human Factors ◽  
Life Sciences ◽  
Space Environment ◽  
Flight Crew ◽  
Successful Completion ◽  
Nasa Ames Research ◽  
Task Training ◽  
Time Required ◽  
Mission Simulation ◽  
First Time

At NASA-Ames Research Center's Life Sciences Flight Experiments Project Office two payloads for the Shuttle Spacelab are currently in development. The first payload, Spacelab-3, will launch in November 1984. Unique life sciences hardware designed to support animals in 0-g will fly for the first time. Flight crew training sessions for the Spacelab-3 astronauts began in June 1982. Human factors involvement is extensive. A thorough understanding of both the 1-g and 0-g environments is necessary. The weightlessness of the space environment creates special conditions; e.g., the time required for a 1-g laboratory experiment significantly increases in 0-g. The transportation of objects in 0-g uses different techniques than on Earth. These considerations, plus others, are incorporated into the design of the Spacelab-3 crew training program. The training begins with payload orientation sessions and then progresses to hardware and experiment task training. After successful completion of task training, the crew participates in phase training which is a full-up mission simulation. Refresher and proficiency training is conducted at appropriate intervals. Throughout the crew training sessions the flight crew has input into the flight procedures and any “crew factors” hardware modifications as needed.

scholarly journals Vertical distribution of 137Cs in forest soil after the ground fires

2019 ◽  
Vol 9 (3) ◽  
pp. 231-240
Author(s):  
I. Davydova ◽  
M. Korbut ◽  
H. Kreitseva ◽  
A. Panasiuk ◽  
V. Melnyk
Keyword(s):  
Forest Fires ◽  
Specific Activity ◽  
Soil Layer ◽  
Forest Products ◽  
Forest Litter ◽  
State Enterprise ◽  
Soil Horizons ◽  
The Difference ◽  
Study Sites ◽  
Time Required

We studied the influence of forest fires on vertical pattern of 137Cs specific activity concentration in forest soils. Our experiments were organized in Bazar forestry of State Enterprise (SE) “Narodychi Forestry” (Ukraine). We sampled soil in the study sites where grassfires occurred at different times, and determined the specific activity of 137Cs in all soil horizons. We determined that the forest fires and burned forest litter intensify mineralization of forest litter nutrients and increase the radionuclide content in upper layers of soil mineral part. In the following years, the radionuclides gradually move to deeper soil horizons and the difference between the burned and control areas decreases. We determined the depth of soil layer, where the changes in 137Cs specific activity occur caused by the forest fires. The time required for restoration of the original distribution is calculated. The results obtained allow us to identify a group of plants (by the location of the root system) that may have increased levels of contamination in the years following a forest fire and to determine the period when we must conduct additional radiological control of them. We suggested the recommendations on usage of non-timber forest products on the territories contaminated with radionuclides.

Uncertainity Analysis for the Fiducial Calibration System

2005 ◽  
Author(s):  
Bethany A. Woody ◽  
K. Scott Smith ◽  
Robert J. Hocken ◽  
Jimmie A. Miller
Keyword(s):  
Uncertainty Analysis ◽  
Shop Floor ◽  
Calibration System ◽  
Finished Part ◽  
Number Of Factors ◽  
Time Required ◽  
First Time

Previous work has established the Fiducial Calibration System (FCS), a technique, which, for the first time provides a method that allows for the accuracy of a CMM to be transferred to the shop floor. This paper addresses the range of applicability of the FCS, and provides a method to answer two fundamental questions. First, given a set of machines and fiducials, how much improvement in precision of the finished part can be expected? And second, given a desired precision of the finished part, what machines and fiducials are required? The achievable improvement in precision using the FCS depends on a number of factors including, but not limited to: the type of fiducial, the probing system on the machine and CMM, the time required to make a measurement, and the frequency of measurement. In this paper, the sensitivity of the method to such items is evaluated through an uncertainty analysis, and examples are given indicating how this analysis can be used in a variety of cases.

scholarly journals NATpare: a pipeline for high-throughput prediction and functional analysis of nat-siRNAs

2020 ◽  
Vol 48 (12) ◽  
pp. 6481-6490 ◽  
Author(s):  
Joshua Thody ◽  
Leighton Folkes ◽  
Vincent Moulton
Keyword(s):  
Functional Analysis ◽  
Messenger Rnas ◽  
Small Interfering Rnas ◽  
Sequencing Data ◽  
Software Pipeline ◽  
Resource Requirements ◽  
Time Required ◽  
First Time ◽  
Specific Mrna

Abstract Natural antisense transcript-derived small interfering RNAs (nat-siRNAs) are a class of functional small RNA (sRNA) that have been found in both plant and animals kingdoms. In plants, these sRNAs have been shown to suppress the translation of messenger RNAs (mRNAs) by directing the RNA-induced silencing complex (RISC) to their sequence-specific mRNA target(s). Current computational tools for classification of nat-siRNAs are limited in number and can be computationally infeasible to use. In addition, current methods do not provide any indication of the function of the predicted nat-siRNAs. Here, we present a new software pipeline, called NATpare, for prediction and functional analysis of nat-siRNAs using sRNA and degradome sequencing data. Based on our benchmarking in multiple plant species, NATpare substantially reduces the time required to perform prediction with minimal resource requirements allowing for comprehensive analysis of nat-siRNAs in larger and more complex organisms for the first time. We then exemplify the use of NATpare by identifying tissue and stress specific nat-siRNAs in multiple Arabidopsis thaliana datasets.

scholarly journals Simultaneous transmission and reception on all elements of an array: binary code excitation

2019 ◽  
Vol 475 (2225) ◽  
pp. 20180831 ◽  
Author(s):  
Julio A. Isla ◽  
Frederic B. Cegla
Keyword(s):  
Binary Code ◽  
Signal To Noise Ratio ◽  
Ultrasound Probe ◽  
Data Throughput ◽  
Element System ◽  
Order Of Magnitude ◽  
Time Required ◽  
Pulse Echo ◽  
First Time ◽  
Non Destructive

Pulse-echo arrays are used in radar, sonar, seismic, medical and non-destructive evaluation. There is a trend to produce arrays with an ever-increasing number of elements. This trend presents two major challenges: (i) often the size of the elements is reduced resulting in a lower signal-to-noise ratio (SNR) and (ii) the time required to record all of the signals that correspond to every transmit–receive path increases. Coded sequences with good autocorrelation properties can increase the SNR while orthogonal sets can be used to simultaneously acquire all of the signals that correspond to every transmit–receive path. However, a central problem of conventional coded sequences is that they cannot achieve good autocorrelation and orthogonality properties simultaneously due to their length being limited by the location of the closest reflectors. In this paper, a solution to this problem is presented by using coded sequences that have receive intervals. The proposed approach can be more than one order of magnitude faster than conventional methods. In addition, binary excitation and quantization can be employed, which reduces the data throughput by roughly an order of magnitude and allows for higher sampling rates. While this concept is generally applicable to any field, a 16-element system was built to experimentally demonstrate this principle for the first time using a conventional medical ultrasound probe.

scholarly journals Journey Planning Algorithms for Massive Delay-Prone Transit Networks

Algorithms ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 2
Author(s):  
Mattia D’Emidio ◽  
Imran Khan ◽  
Daniele Frigioni
Keyword(s):  
Query Time ◽  
Planning Problem ◽  
The Public ◽  
Transit Networks ◽  
Interactive Applications ◽  
Time Required ◽  
Query Algorithm ◽  
First Time ◽  
New Algorithms ◽  
New Framework

This paper studies the journey planning problem in the context of transit networks. Given the timetable of a schedule-based transportation system (consisting, e.g., of trains, buses, etc.), the problem seeks journeys optimizing some criteria. Specifically, it seeks to answer natural queries such as, for example, “find a journey starting from a source stop and arriving at a target stop as early as possible”. The fastest approach for answering to these queries, yielding the smallest average query time even on very large networks, is the Public Transit Labeling framework, proposed for the first time in Delling et al., SEA 2015. This method combines three main ingredients: (i) a graph-based representation of the schedule of the transit network; (ii) a labeling of such graph encoding its transitive closure (computed via a time-consuming pre-processing); (iii) an efficient query algorithm exploiting both (i) and (ii) to answer quickly to queries of interest at runtime. Unfortunately, while transit networks’ timetables are inherently dynamic (they are often subject to delays or disruptions), ptl is not natively designed to handle updates in the schedule—even after a single change, precomputed data may become outdated and queries can return incorrect results. This is a major limitation, especially when dealing with massively sized inputs (e.g., metropolitan or continental sized networks), as recomputing the labeling from scratch, after each change, yields unsustainable time overheads that are not compatible with interactive applications. In this work, we introduce a new framework that extends ptl to function in delay-prone transit networks. In particular, we provide a new set of algorithms able to update both the graph and the precomputed labeling whenever a delay affects the network, without performing any recomputation from scratch. We demonstrate the effectiveness of our solution through an extensive experimental evaluation conducted on real-world networks. Our experiments show that: (i) the update time required by the new algorithms is, on average, orders of magnitude smaller than that required by the recomputation from scratch via ptl; (ii) the updated graph and labeling induce both query time performance and space overhead that are equivalent to those that are obtained by the recomputation from scratch via ptl. This suggests that our new solution is an effective approach to handling the journey planning problem in delay-prone transit networks.

scholarly journals Experimental Study on Strength Influencing Factors of Calcareous Nodule Soil in Northern Jiangsu

2021 ◽  
Author(s):  
Xiaolong Wang ◽  
Jianling Gu ◽  
Song Xu ◽  
Shengdong Gu
Keyword(s):  
Particle Size ◽  
Water Content ◽  
Soil Layer ◽  
Physical And Mechanical Properties ◽  
Triaxial Tests ◽  
Long Time ◽  
Confining Pressures ◽  
Calcareous Concretion ◽  
Time Required ◽  
The Impact

The physical and mechanical properties of calcareous concretion soil depend largely on the shape, size and distribution of calcareous concretion soil besides the impact of soil layer. Due to the long time required for clay saturation, consolidation, and shearing, as well as the tedious sample preparation, larger triaxial tests of calcareous nodules have not been carried out. In this chapter, based on the medium triaxial test of calcareous nodules, the strength characteristics of remolded soil samples under different confining pressures are studied. By controlling parameters such as calcareous nodules particle size and water content, the impact of different test conditions on the strength of calcareous nodules is analysed, and the variation rule is analysed. It is concluded that the impact of nodular particle size on soil strength is not obvious at 20% nodular content. The impact of different water content on the strength of soil is more regular, showing hardening characteristics, in line with the natural law.

Sign in / Sign up

Export Citation Format

Share Document