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Online since: February 2014
Authors: Lin Luo, Fu Wen Hu, Nai Song Zhang
In terms of the measured data, vibration, acoustic, temperature and pressure are often selected to be monitored.
However, these and other previous researches have not changed the data presentation mode of the signals.
Although data visualization has been considered a powerful way to simplify complexity, it has not been reported that data visualization is used to machine health monitoring.
Then the data are transferred into the host computer and the real-time artistic graph is created by the graph production system.
The observer can assign the valuable machine state to the corresponding artistic graph and save them into the data base.
Online since: July 2014
Authors: Gu Yong
Finally, it was triumphantly used in simulation of the superheated steam temperature reduction control system of 500 MW unit and food performances are obtained.
Aiming at a super heated temperature control system with high nonlinear, and time-varying characteristic of a boiler, a new kind of intelligent control method- wavelet neural network based internal model control system was proposed in this paper, and it has been applied in the 1st superheated steam temperature reduction control system of 500 MW unit and the simulation results has shown its efficiency.
The network has advantages of the wavelet transform (in background reduction and recovery of characteristic information) and also has neural network capacity of “universal” approximation.
Supposing the nodes number, the output of the of implicit layers are network are defined as: (1) where the weight value of the network can be get from Eq. (2): (2) The network training error performance index is shown in Eq. (3) (3) where N is the training data examples; the error function of the real output and the expecting output is expressed by the following equation: (4) To approximate error function by the same WNN, Eq. (5) is obtained:
Online since: February 2018
Authors: Jan L. Vítek, David Čítek, Pavel Jursík
More resilient connection of shear sheets to the top flange and a high resistance of UHPC allow for reduction of the extent of shear connectors.
During the experiment it has been proven that the performance of the beams with both variants of shear connection is very similar even with the significant reduction of the extent of shear connectors.
Numerical Analysis The main goals of the numerical analysis are proving the possibility of reducing the amount of shear connectors, evaluating of influence of the reduction of extent of shear connectors on stiffness of the girder in bending, evaluating of load bearing capacity of the new proposed shear connection, description of its behavior and description of the stress state around the local puzzle sheets.
It was proven that the new proposed connection of precast elements providing also the shear connection of the precast deck and the steel structure is able to resist combined loading and it is not a cause of any reduction of stiffness in bending and thus the proposed connection has no influence on distribution of internal forces and it can serve as full shear connection [4].
In the future there should be gathered more data and information from experimental measurements for determining of load bearing capacity of this type of shear connection.
Online since: October 2015
Authors: Adrian Catangiu, Dan Nicolae Ungureanu, Veronica Despa, Carmen Adriana Cîrstoiu, Alexandru Ioan Ivan
Because the microgripper arm has a reduction of section in the compliance area, for mathematical modeling the beam will be considered with a constant section, by applying a correction factor that will take into account the effect of the compliance.
The bending deformation force was measured using a quartz crystal balance, and the deformation was measured with a Laser triangulation system Keyence LK-G3001PV (with a precision of 0.05 μm), which allows recording data by a specific software.
Experimental setup for determining the compliance effect The experimental results for the two section reduction (compliant) arms of the microgripper are shown in Fig. 5.
Force-deformation dependence on bending tests performed on section reduction arms The slope of the curve represents the value of the elastic constant.
In order to achieve the model of the compliance effect, tests were carried out on the arms with and without section reduction, from which a global elastic correction coefficient Kg, was determined.
Online since: August 2020
Authors: Taras Shnal, Serhii Pozdieiev, Stanislav Sidnei, Oleksandr Nuianzin
In the research [7], a scientifically-substantiated sequence of procedures was created, with a detailed selection of equipment and test samples, in order to provide reliable experimental data when studying the temperature regime of a fire.
Nomogram for determining the coefficients of tensile strength (a) reduction, compressive strength (b) reduction and tensile modulus (c) reduction to design fire-resistant steel building structures at Am/V = 150 [m-1].
I-beam profile according to DSTU 8768:2018 Geometric characteristics of cross-sections Cross-section coefficient Am/V, [m-1] Resistance moment, Wx, [m3] Profile № 55 157.842 2000×10-6 Profile № 40 123.246 947×10-6 Profile № 27а 93.684 407×10-6 Using the data in tab. 2, we can determine the boundary moment using the formula [1]: Mc,Rd=Mpl,Rd=WplfyγM0
Fig. 9 shows that the obtained data can be used to build nomograms to determine the corresponding beam boundary moment.
Analyzing the data shown in fig. 11, it can be observed that in almost all the area of the possible values of the opening coefficients and fire load density, the time of reaching the boundary state of the loss of load-bearing capacity is much greater for the temperature regimes determined by the proposed mathematical models than the values obtained using the standard temperature regime of fire.
Online since: December 2019
Authors: Janis Andersons, Ugis Cabulis, Mikelis Kirpluks
The value of the numerical prefactor was determined by fitting Eq. 1 to the strength data of isotropic foams, for which R=1 and f1=1, resulting in C=0.3 for plastic foams [12].
Using the data presented in [4], the reinforcement efficiency factor Γ was evaluated by Eq. 5 and plotted in Fig. 1 as a function of CNC volume fraction νc in the monolithic PU.
The presence of the filler led to a reduction in the cell size without apparent changes in their geometrical anisotropy, as in [4].
It is seen in Fig. 3 that most of strength data are close to the prediction employing the values of ηo based on Eqs. 9 and 10.
Reinforcement efficiency factor of strength of nanocomposite PU foams vs CNF volume fraction as derived from experimental data [8] (markers) and predicted by Eq. 5 (lines) Summary With the aim to separate the nanofiller reinforcement effect from the foam strength changes caused solely by variation in foam density, a reinforcement efficiency factor of foam strength is introduced.
Online since: May 2015
Authors: Hong C. Rhim, Dae Jin Kim, Seong Hoon Jeong, Kwang Ho Lee, Won Seok Jang, Jong Hwan Park
Abstract The use of steel-concrete composite members has been significantly increased as they have the advantages of the reduction of cross sectional areas, excellent ductility against earthquake loadings and a longer life span than typical steel frame members.
The use of steel-concrete composite members has been significantly increased with such a trend as they have the advantages of the reduction of cross sectional areas, excellent ductility against earthquake loadings and a longer life span than typical steel frame members.
This system has the advantages of reduced floor height and simplified formwork, which can in turn produce many beneficial effects such as the reduction of structure weight, fast construction and great savings in the amount of construction materials and labor.
The load-versus-slip data were recorded throughout the entire loading history using a computer-aided data acquisition system.
Online since: March 2015
Authors: Aldo Fanchiotti, Luca Evangelisti, Luciano Santarpia, Gabriele Battista, Claudia Guattari
It has been demonstrated that the proposed plant allows to reduce the fossil fuels consumption compared to a plant conventionally employed, with a proportional reduction of the greenhouse gas emissions of about 30% per year.
Output data obtained by TRNSYS can be used as input for RETScreen application.
Opaque component Thickness [cm] Thermal Transmittance [W/m2K] Roof 39.3 0.122 Floor 46.8 0.100 External wall 39.9 0.123 Internal wall 39.3 0.125 Results and Discussion Due to the residential destination use of the building, it was imposed in TRNSYS the weather data of Rome and, regarding the set point temperature range, a temperature equal to 20°C during the winter and a temperature equal to 26°C during the summer has been taken into account.
Table 2 – Greenhouse gases emission for the conventional plant Type of fuel Fuel mix Fuel consumption [MWh] Greenhouse gases emission per MWh [tCO2/MWh] Greenhouse gas emission [tCO2] Natural gas 12.8 % 31 0.197 6.1 Electrical energy 87.2 % 210 0.374 78.6 Total 100 % 241 0.351 84.7 Table 3 – Greenhouse gas emission for the proposed plant Type of fuel Fuel mix Fuel consumption [MWh] Greenhouse gases emission per MWh [tCO2/MWh] Greenhouse gas emission [tCO2] Biomass 13.9 % 34 0.007 0.2 Solar energy 18.2 % 44 0.000 0.0 Electrical energy 67.8 % 163 0.374 61.0 Total 100 % 240 0.255 61.2 It is worthy to notice that, despite a comparable energy fuel consumption, employing the proposed plant it can be assessed a significant reduction of greenhouse gas emissions.
The proposed plant - composed by a heat pump for the cooling demand, a photovoltaic plant for the electrical demand and a pellet boiler for heating demand - allows to avoid the fossil fuels with a consequent reduction of the greenhouse gas emissions of about 28% per year.
Online since: April 2012
Authors: Víctor H. Jacobo, Armando Ortiz, Hugo A. Duran, Rafael Schouwenaars
The work is exploratory in nature in the sense that, while ample data for mechanical properties were obtained [4], the measurement campaign for macro- and microtexture is much more limited.
In spite of this limited set of data, interesting conclusions will be presented, both in terms of the specific recrystallisation and grain growth characteristics and on the differences with recrystallisation mechanisms in classical commercial Al-alloys.
Only small increases in strength were obtained by these reductions, while ductility was decreased, which is the reason why the present work focuses on smaller reductions, although results on grain growth obtained from samples with the higher reductions will also be presented.
{111} recalculated pole figures for the as-cast product, 70 and 95% reduction.
Few studies have been dedicated to the study of recrystallisation in alloys with a contiguous second phase [11] and even less data are available on recrystallisation and grain growth in the presence of a liquid phase [17,18].
Online since: June 2018
Authors: Min Seok Kang, Bong Mook Lee, Veena Misra
This improvement can be attributed to the effective removal of unreacted metal-organic precursors, active traps, and broken bonds in the ALD SiO2 dielectrics as well as reduction in interface state density at SiC/SiO2 interface.
It is well known that the subthreshold swing is directly related to the interface state density [9] so the steep slope obtained from the Sample #5 indicates the reduction of interface state density at the SiC/SiO2 interface resulting in the enhancement of the channel mobility.
These improvements can be explained by the fact that the multiple deposition with multiple anneal effectively suppresses electron traps by removing unreacted metal-organic precursors from the SiO2 ALD process as well as passivates SiC/SiO2 interface resulting in the reduction interface trap density (Dit).
The information, data, or work presented herein was funded in part by the Office of Energy Efficiency and Renewable Energy (EERE), U.S.
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