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Online since: March 2011
Authors: Augusto Barata da Rocha, Marta Oliveira, João P. Santos, Fernando G. Almeida, Ana Reis, João P.G.T. Pereira
It must be noted that the technical evolution towards higher Laser power has been followed with a continuous components and package size reduction, creating significant challenges to the Laser cooling engineers.
While the technical benefits related to the integration of fewer components are intuitive to promote the environmental performance of the FL technology, data on the energy savings benefits are still on the hands of few manufacturers, and only some parallel estimation has been recently available.[6] Moreover, besides the Laser and cooling units, other important electrically fed sub-systems, such as the general control unit (including the motorized head positioning) and the exhaustion system, should be considered on the analysis of the energy demand of a Laser cutter.
This work brings out complete data on the electrical energy demand of CO2- and FL-based equipments, right from the application field, essential for a reliable and accurate technology comparison, providing the proper support for the specification of an improved machine.
The power measurement equipment and conditions used, as well as the theoretical background applied in the power and energy data treatment is explained in a previous work [8].
This would result on a significant reduction on the power demand of the chiller and on its improved efficiency.
Online since: July 2003
Authors: Gyuhae Park, A.L. Cundy, Francois M. Hemez, Daniel J. Inman
This empirical fit allows models to be constructed that relate damage parameters of interest (such as stiffness reduction and its location) to measurable output features (e.g. natural frequencies).
It could be a traditional reduced order model (as obtained from Guyan reduction or Craig-Bampton methods), a neural network, or a statistically derived model.
Metamodels may then be fit to these intelligently chosen data points using standard multiple regression methods resulting in a polynomial model that relates input parameters to output features.
Higher error was expected at the stiffnesses (3000, 5000) and locations (2, 4) that were not included in the training data set and this was observed.
Forward relationships may be generated with relatively few "training" data sets and the inverse formulation may then be applied to conduct damage identification with some quantifiable degree of accuracy.
Online since: March 2014
Authors: Dao Lun Chen, F.A. Mirza, De Jiang Li, Xiao Qin Zeng
To manufacture lighterweight vehicles, substantial reductions could be achieved by employing ultra-lightweight magnesium (Mg) alloys [2,3].
Despite the potential of substantial reductions in weight, most wrought Mg alloys exhibited a high degree of anisotropy and tension-compression yield asymmetry [4-7].
The fatigue life (i.e., the number of cycles to failure, Nf) as a function of the applied total strain amplitudes (Δεt/2) of the extruded GW103K alloy is plotted in Fig. 5(a), along with the experimental data reported in the literature for various extruded Mg alloys [6,7,15] for comparison.
Run-out data points were indicated by arrows pointing horizontally at or more than 107 cycles.
(b) (a) Fig. 5 (a) Total strain amplitude as a function of the number of cycles to failure for the extruded GW103K alloy, in comparison with the data reported in the literature for various extruded Mg alloys, and (b) cyclic stress-strain curves of the present alloy, where the corresponding monotonic stress-strain curve is also plotted for comparison.
Online since: November 2010
Authors: Xin Chen, Jian Ping Tan, Zhong Yun
Due to the large amount of data produced in this simulation, velocity magnitude contours are shown for selected parts of the flow domain.
Data Reduction.
Accord to the analysis of Data Reduction , the exposure time of maxima stress for the CFD model is effective, which may bring the particle damaged.
By performing a reduction to simple loading functions and separating the damaged parts of the loading functions from the nondamaged, the ratio trauma of blood cells can be estimated from the amount of cells damaged due to the lysis of cells at the wall according to the threshold shear stress.
Online since: September 2013
Authors: Ming Ke, Zhao Zheng Song, Xi Ming Yan
The standard of vehicle gasoline formulated by the National Environmental Protection Agency, it required the olefin content should not be exceed 25%, this higher than the European standard(not exceed 18%), However, due to the structure of petroleum products is unreasonable, the olefin content did not meet the standard in the majority of China’s refineries, Therefore, it is necessary to develop olefin reduction technology.
Some common gasoline olefin reduction technology included: Selective hydrogenation, Development catalyst and additives of olefin reduction, Back refining technology, Aromatization, Etherification,etc[1].
It shows that the characteristic peaks of γ-Al2O3 and Hβ are observed in all catalyst and their XRD data compared similar to each other, this indicate that the hydrothermal modification does not change crystalline structure of catalysts, they have good thermal stability.
NH3-TPD data graph for these modified catalysts is shown in Fig.4.
The Fig.6 shows that the characteristic peaks of γ-Al2O3 and Hβ in all catalysts and their XRD data similar to each other, this proved once again that the hydrothermal modification does not change crystalline structure of the modified catalysts and these catalysts have good thermal stability.
Online since: February 2014
Authors: Dominik Gazdič, Marcela Fridrichová, Iveta Hájková
The raw material base of belite cements require less lime than production of common Portland cements and on that ground the implementation of its production would be a positive benefit for ecology in sense of CO2 emission reduction and also in improvement of economy of non-renewable raw material sources.
In addition at reduction of the temperature for more than 100 °C also heat consumption is reduced for 10 to 14 %, which has positive economical and ecological effects due to lower consumption of fuels.
Duda, Cement-data-book, Bauverlag GmbH - Wiesbaden and Berlin, ISBN 3-7625- 0180-7, Berlin, 1976
Online since: May 2011
Authors: Wen Xue Gao, Wen Long Sun, Hong Liang Deng, Xi Meng Sun
Study on Blasting Vibration Effects of Shallow Tunnel Excavation Wenxue Gao1,a,Wenlong Sun2,b,Hongliang Deng 1,c and Ximeng Sun 2,b 1Beijing University of Technology,Beijing,100124,China 2Beijing Roads and Bridges Construction Group Corporation Limited,Beijing,100068,China awxgao@bjut.edu.cn,bbjlqazb@126.com,cdenghongliang@bjut.edu.cn Keywords: Shallow Tunnel; Blasting Excavation; Monitoring Of Blasting Vibration; Vibration Reduction Technology.
The paper studies the characteristics and its spreading rule of the shallow tunnel excavation surface vibration and puts forward vibration control technology of the shallow tunnel excavation on the basis of the tunnel segment blast vibration monitoring and data analysis of the Mi-xing road reconstruction project.
The speed sensor is fixed in monitoring spot, and the sensors and data recorder are linked together, and the collecting device is adopted during the process.
The data recorded is put into the analysis software to get speed time-history curve, and the collected data is processed and analyzed by analyzing software.
Online since: March 2015
Authors: Yong Feng Luo, Xi Yu Wang, Xu Hong Qiang, Xiao Liu
This is due to the lack of research data available and hence a deeper parametric study is of urgent need.
Može et al. [9] conducted FE analysis on specimens of S690 steel and compared the result with data of 38 specimens in other literature, most of which were analyzed by FEM.
To systematically look into this area, one still has to refer to the large quantity of research data on mild steel connections.
These results also highlighted the importance of using robust FE models to explain these observations and to provide data on which to base simplified design models.
Data offered by experimental and finite element analysis could be processed to build a numerical model. 2.
Online since: January 2022
Authors: Romildo Dias Toledo Filho, Patrícia Brandão Souza, Giulia Fea Oliveira, Rayane de Lima Moura Paiva, Lucas Rosse Caldas
Our research links experimental data with thermal-energy simulations and LCA, delivering a holistic analysis of a novel and non-conventional material.
Life cycle inventory (LCI) For the Life Cycle Inventory (LCI) stage, primary data is collected from the laboratory, while for secondary data, the Ecoinvent v. 3.6 and scientific literature are used.
Based on these data and assumptions, we found a value of 1.62 kgCO2/kg of bamboo, which resulted in 1.21 kgCO2/m², 2.42 kgCO2/m², and 3.64 kgCO2/m² for EMB3, EMB6, and EMB9, respectively.
We consider that the CaO in cement is 0.55 and 0.70 in hydrated lime, based on manufacturers’ data.
Based on these data and assumptions, we found that, for earth mortars (EMB0, EMB3, EMB6, and EMB9), it is possible to capture 2.67 kgCO2/m² (they present the same value since all of them have the same amount of cement and hydrated lime), and for conventional mortars CMS1:3:12, we found the value of 5.31 kgCO2/m² and 6.02 kgCO2/m² for CMS1:2:8.
Online since: December 2023
Authors: Qing Lian Li, Xin Lin Liu, Lan Wei Chen, Jun Sun, Jie Song
A new correlation expressed by Bo, We, Kp, X, Co, Ftg is proposed, which yields good fitting for 355 experimental data with a mean absolute error (MAE) of 10.9%.
It includes the methane dewar, high pressure methane tank, vacuum tank, test section, evaporator, mass flowmeter, data acquisition device, and DC power, etc.
Data Reduction The experimental measurement parameters include: temperature and pressure at the inlet and outlet of the test section, temperature of the outer wall of the test section (at 10 different positions), methane mass flow rate.
Heat transfer correlation Based on the experimental data, a correlation of Nusselt number for subcritical methane in vertical tube was proposed as shown in Eq.(4-1).
(4-1) The methane flow boiling heat transfer correlation was based on the mass quality division criterion, which can accurately predict 355 groups of experimental data, with an mean absolute error (MAE) of 10.9% (Fig.7)
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