scholarly journals The Modulus of Resilience for Critical Subsystems

2020 ◽  
Author(s):  
Eric Easton ◽  
Mario Beruvides ◽  
Andrea Jackman
Keyword(s):  
Modulus Of Resilience ◽  
Critical Subsystems

Operation and approximation based on the history of failure modes recorded by SCADA system of Amougdoul Moroccan wind farm using FMECA maintenance model

2021 ◽  
pp. 0309524X2199245
Author(s):  
Kawtar Lamhour ◽  
Abdeslam Tizliouine
Keyword(s):  
Wind Turbines ◽  
Wind Farm ◽  
Failure Modes ◽  
Wind Farms ◽  
Scada System ◽  
History Of ◽  
Criticality Analysis ◽  
Maintenance Model ◽  
Reliability And Availability ◽  
Critical Subsystems

The wind industry is trying to find tools to accurately predict and know the reliability and availability of newly installed wind turbines. Failure modes, effects and criticality analysis (FMECA) is a technique used to determine critical subsystems, causes and consequences of wind turbines. FMECA has been widely used by manufacturers of wind turbine assemblies to analyze, evaluate and prioritize potential/known failure modes. However, its actual implementation in wind farms has some limitations. This paper aims to determine the most critical subsystems, causes and consequences of the wind turbines of the Moroccan wind farm of Amougdoul during the years 2010–2019 by applying the maintenance model (FMECA), which is an analysis of failure modes, effects and criticality based on a history of failure modes occurred by the SCADA system and proposing solutions and recommendations.

scholarly journals Test Study on Road Performance of Soils Stabilized by Liquid Stabilizer in Seasonally Frozen Regions

2012 ◽  
Vol 5 ◽  
pp. 310-315 ◽  
Author(s):  
Yao Chen ◽  
Yi Qiu Tan
Keyword(s):  
Water Resistance ◽  
Base Material ◽  
Road Construction ◽  
Penetration Resistance ◽  
Comprehensive Investigation ◽  
Test Study ◽  
Stabilized Soil ◽  
Road Performance ◽  
Modulus Of Resilience ◽  
Seasonally Frozen Regions

In seasonally frozen regions, road construction often suffers from low strength,lack of durability, etc. Improving the typical clay’s workability in Changchun with lime and the Base-Seal stabilizer (BS-100) shows promising results. A comprehensive investigation to assess the soil characteristics influence is undertaken, so as the lime and liquid stabilizer (BS-100) content on the physical properties of stabilized soils in seasonally frozen regions. The optimum mix proportions, unconfined compressive strength, splitting strength, modulus of resilience, freeze-thaw action, water resistance and penetration-resistance were outlined. By comparing with current specifications, the Base-Seal stabilized soil as base material has higher early strength, higher after-strength and better frost stability.The results can be applied in road construction in seasonally frozen regions.

scholarly journals Investigation on cement-improved phyllite based on the vertical vibration compaction method

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247599
Author(s):  
Yingjun Jiang ◽  
Jiangtao Fan ◽  
Yong Yi ◽  
Tian Tian ◽  
Kejia Yuan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Static Pressure ◽  
Cement Content ◽  
Vertical Vibration ◽  
Pressure Method ◽  
Vibration Compaction ◽  
Modulus Of Resilience ◽  
Compaction Method

The vertical vibration compaction method (VVCM), heavy compaction method and static pressure method were used to form phyllite specimens with different degrees of weathering. The influence of cement content, compactness, and compaction method on the mechanical properties of phyllite was studied. The mechanical properties of phyllite was evaluated in terms of unconfined compressive strength (Rc) and modulus of resilience (Ec). Further, test roads were paved along an expressway in China to demonstrate the feasibility of the highly weathered phyllite improvement technology. Results show that unweathered phyllite can be used as subgrade filler. In spite of increasing compactness, phyllite with a higher degree of weathering cannot meet the requirements for subgrade filler. With increasing cement content, Rc and Ec of the improved phyllite increases linearly. Rc and Ec increase by at least 15% and 17%, respectively, for every 1% increase in cement content and by at least 10% and 6%, respectively, for every 1% increase in compactness. The higher the degree of weathering of phyllite, the greater the degree of improvement of its mechanical properties.

Signal Coordination and Arterial Capacity in Oversaturated Conditions

2000 ◽  
Vol 1727 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Ghassan Abu-Lebdeh ◽  
Rahim Benekohal
Keyword(s):  
Queue Length ◽  
Processing Capability ◽  
Signal Coordination ◽  
Capacity Loss ◽  
Explicit Function ◽  
Queue Lengths ◽  
Input Variables ◽  
Intersection System ◽  
Critical Subsystems ◽  
Critical Subsystem

Models for estimation of the capacities of oversaturated arterials were developed. The input variables in these models are capacities of individual intersections, offsets, and vehicle queue lengths. Models for quantification of capacity loss due to blockage caused by downstream queues are also presented. The proposed models show that when arterial capacity is determined in oversaturated conditions, it is not sufficient to consider only the capacities of critical intersections; instead, the capacities of critical subsystems must be considered. A critical subsystem is any two intersections plus the link that joins them where traffic processing capability is the lowest. This traffic processing capability, or critical subsystem capacity, determines the arterial capacity. It is a function of the capacities of the respective intersections, the offset between them, and the queue length on the link joining them. It is shown that a critical subsystem is not unique in that it may change location over the course of the study period. To minimize capacity loss, it is shown that offsets must be an explicit function of queue lengths. The practical use of the models was demonstrated for an oversaturated two-intersection system. The results show that improper setting of offsets can lead to significant capacity loss. In extreme cases all capacity in a given cycle may be lost if the offsets are not set properly.

Experimental Study on Mechanical Behaviors of Lime-Stabilized Soils with Small Lime Content

2011 ◽  
Vol 374-377 ◽  
pp. 1823-1826
Author(s):  
Zhong Yu Liu ◽  
Yong Gang Xue ◽  
Xi Jun Wang
Keyword(s):  
Compression Strength ◽  
Compression Modulus ◽  
Curing Time ◽  
Test Results ◽  
Unconfined Compression Strength ◽  
Unconfined Compression ◽  
Mechanical Behaviors ◽  
Lime Content ◽  
Modulus Of Resilience ◽  
Resilience Modulus

In order to investigate the mechanical behaviors of lime-stabilized soils with small lime content, the specimens with 4%~8% lime content and 90%~95% degree of compaction are prepared, and then in use for the unconfined compression strength test, the diametral compression test and the compression resilience modulus test after they have cured in a standard curing room for 7 to 180 days respectively. These test results show that all of the unconfined compression strength, the splitting strength and the compression modulus of resilience increase with the degree of compaction and the curing time. Thereinto, the compression modulus of resilience does rapidly between 28 and 90 curing days, and the unconfined compression strength of the soil with 4% lime content does little after 28 curing days while the compression strengths and the splitting strengths of the other soils do quickly until 90 curing days. In addition, for a given degree of compaction, these strengths of the soils with the less lime content are potentially greater at the early curing time.

scholarly journals Minimal Critical Subsystems for Discrete-Time Markov Models

2012 ◽  
pp. 299-314 ◽  
Author(s):  
Ralf Wimmer ◽  
Nils Jansen ◽  
Erika Ábrahám ◽  
Bernd Becker ◽  
Joost-Pieter Katoen
Keyword(s):  
Discrete Time ◽  
Markov Models ◽  
Critical Subsystems

scholarly journals Experimental Study on the Effect of Compaction Work and Defect on the Strength of Soil-Rock Mixture Subgrade

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Xin Yan ◽  
Wei Zhan ◽  
Zhi Hu ◽  
Yiqiang Yu ◽  
Danqiang Xiao
Keyword(s):  
Resilient Modulus ◽  
Good Condition ◽  
Stress Transfer ◽  
Loose Body ◽  
Earth Dam ◽  
Filling Material ◽  
Test Results ◽  
Engineering Characteristics ◽  
Modulus Of Resilience ◽  
Geotechnical Tests

Soil-rock mixture is a common filling material for earth dam and subgrade. In this study, research concerned on the evolution law of engineering characteristics of soil-rock mixture under different factors and the effect of defect on subgrade strength, and geotechnical tests were carried out to analyze the influence of different factors on engineering characteristics of soil-rock mixture in the study, and the physical model was carried out to analyze the effect of different compaction works on the resilient modulus, and the influence of defect on the strength was explored by manually preset loose body. The test results showed that (1) when the soil-rock mixture was graded, P = 78, the moisture content was 14%, and the engineering characteristics were optimal; (2) there was a positive correlation between compaction times and resilient modulus, and the stress transferred from the subgrade to soil was linearly distributed under the good condition of compactness; and (3) the existence of loose body not only reduces the modulus of resilience but also affects the stress transfer; the larger the loose body, the lower the resilient modulus and the greater the stress transfer.

Materials Testing for Mechanical Properties—Problems and Solutions

2021 ◽  
pp. 19-37
Keyword(s):  
Mechanical Properties ◽  
Copper Alloys ◽  
Strain Hardening Exponent ◽  
Materials Testing ◽  
Wide Range ◽  
Problems And Solutions ◽  
Machine Stiffness ◽  
Modulus Of Resilience ◽  
As Stress

Abstract This appendix provides readers with worked solutions to 25 problems involving calculations associated with tensile testing and the determination of mechanical properties and variables. The problems deal with engineering factors and considerations such as stress and strain, loading force, sample lengthening, and machine stiffness, and with mechanical properties and parameters such as elastic modulus, Young’s modulus, strength coefficient, strain-hardening exponent, and modulus of resilience. They also cover a wide range of materials including various grades of aluminum and steel as well as iron, titanium, brass, and copper alloys.

Sign in / Sign up

Export Citation Format

Share Document