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Online since: August 2014
Authors: Klaus Dilger, Thomas Nitschke-Pagel, Jonas Hensel
The presented work is on welded specimens, made of unalloyed fine grained carbon steel, with different fatigue crack lengths.
The material used for the specimens was an unalloyed fine-grained mild construction steel (steel grade 1.0546) with a yield strength (Re) of 360 MPa.
In particular, the samples were loaded to a pre-defined number of load cycles and stopped resulting in different fatigue crack lengths at the weld toe.
The stress range Ds used for testing is plotted over the corresponding number of load cycles N for a given failure criterion (e.g. specimen fracture or a given crack length).
The material used for the specimens was an unalloyed fine-grained mild construction steel (steel grade 1.0546) with a yield strength (Re) of 360 MPa.
In particular, the samples were loaded to a pre-defined number of load cycles and stopped resulting in different fatigue crack lengths at the weld toe.
The stress range Ds used for testing is plotted over the corresponding number of load cycles N for a given failure criterion (e.g. specimen fracture or a given crack length).
Vibration-Based Terrain Identification for Planetary Exploration Robots Using Support Vector Machine
Online since: November 2012
Authors: Kai Xue, Wen Lin Pan, Qiang Li, He Xu, Zhi Xu Li
Facing to the same number of votes, we propose a new algorithm.
Because objective of classification is to adjust control strategy and ensure the robot safely travel through the terrain, sequence numbers of the terrains arranged in order of difficulty level that small sequence number terrain is traveled easier than the big.
To each terrain, there were fifty-four samples, and where odd numbers of samples were trained, so there were twenty-seven training samples.
It reduces number of dimensions and improves classification efficiency.
Prior to classify, sequence numbers of the terrains arranged in order of difficulty level that small sequence number terrain is traveled easier than the big.② if isn’t the first of classifying samples, it belongs to the terrain which is the previous sample.
Because objective of classification is to adjust control strategy and ensure the robot safely travel through the terrain, sequence numbers of the terrains arranged in order of difficulty level that small sequence number terrain is traveled easier than the big.
To each terrain, there were fifty-four samples, and where odd numbers of samples were trained, so there were twenty-seven training samples.
It reduces number of dimensions and improves classification efficiency.
Prior to classify, sequence numbers of the terrains arranged in order of difficulty level that small sequence number terrain is traveled easier than the big.② if isn’t the first of classifying samples, it belongs to the terrain which is the previous sample.
Online since: February 2015
Authors: Yi Ping Chen, Dong Hai Cheng, Qi Fan
The nugget were mainly composed of equiaxial grains and cellular dendrites.
The sufficient constitutional supercooling appears to be necessary for the formation of equiaxed dendritic crystal.On the one hand, the solute equilibrium distribution coefficient of Mg and Li atoms in Al were less than 1 results in Mg and Li enriched at solid-liquid interface, the crystals with lesser constraint gets into liquid phase much easier, which promotes growth of equiaxed dendritic crystal .On the other hand, large amount of Al3Zr particles would be formed from 0.11% Zr of 5A90 in the welding , increasing the nucleation rate of α(Al),that is the reason why heterogeneous nucleation develops smoothly.The crystal nucleus take hold and grow on Al3Zr particles,reducing the surface energy, nucleating and growing with a lower the supercooling degree.A number of processes is formed locally as α(Al) extended along the direction of supercooling,which could be more conducive to solidify.As solidification progresses,the crystal nucleus growth extended forward and some side-branches appeared
Moreover, the interaction of welding current and induced magnetic field compelled the molten metal to rotate and bend, increasing the number of dendrites fractured of α(Al) .
The sufficient constitutional supercooling appears to be necessary for the formation of equiaxed dendritic crystal.On the one hand, the solute equilibrium distribution coefficient of Mg and Li atoms in Al were less than 1 results in Mg and Li enriched at solid-liquid interface, the crystals with lesser constraint gets into liquid phase much easier, which promotes growth of equiaxed dendritic crystal .On the other hand, large amount of Al3Zr particles would be formed from 0.11% Zr of 5A90 in the welding , increasing the nucleation rate of α(Al),that is the reason why heterogeneous nucleation develops smoothly.The crystal nucleus take hold and grow on Al3Zr particles,reducing the surface energy, nucleating and growing with a lower the supercooling degree.A number of processes is formed locally as α(Al) extended along the direction of supercooling,which could be more conducive to solidify.As solidification progresses,the crystal nucleus growth extended forward and some side-branches appeared
Moreover, the interaction of welding current and induced magnetic field compelled the molten metal to rotate and bend, increasing the number of dendrites fractured of α(Al) .
Online since: July 2012
Authors: Zhi Xiang Hou, Tao Wang, Dong Chen Zhang
The optimum technological combination of flocculation test has been obtained:incubation time:12h,Coagulation aid dosage:2mL,Bacterium fluid amount:2mL,The categories of flocculants: the cell homogenates,pH:7.The FTIR analysis showed that the extractive of Rhodopseudomonas spheroides contain a large number of acidic Polysaccharides which has flocculent effect component.The main flocculation is “adsorption-bridge” between Molecular bioflocculant and coal slurry.
Introduction Coal slurry is industrial wastewater which was used in coal washing and dressing,the main charateristic of coal slurry is fine grained, high-ash and mostly negative charge on particle surface[1].Pea coal distributes in water as seperated type occurrence,usually use APAM to increase the sedimentation of fine particles suspended in coal slurry[2],however its high price and the large usage,not only raise costs of production but also increased pollution of the environment.
Specification: ScannerVelocity: 100kHz; Beamsplitter: KBr; X-axle: wave number(/cm-1);y-axle:transmitance(/%).
Introduction Coal slurry is industrial wastewater which was used in coal washing and dressing,the main charateristic of coal slurry is fine grained, high-ash and mostly negative charge on particle surface[1].Pea coal distributes in water as seperated type occurrence,usually use APAM to increase the sedimentation of fine particles suspended in coal slurry[2],however its high price and the large usage,not only raise costs of production but also increased pollution of the environment.
Specification: ScannerVelocity: 100kHz; Beamsplitter: KBr; X-axle: wave number(/cm-1);y-axle:transmitance(/%).
SPS Temperature Influence on the Composition, Structure and Magnetic Properties of Hematite Ceramics
Online since: September 2021
Authors: Alexander S. Samardak, Evgeniy Papynov, Alexey Ognev, Vladimir Pechnikov
Secondly, increasing the grain size reduces the number of defects, such as grain boundaries, the magnetization of which is less in the grain.
An active grain growth is observed with an increase in the SPS temperature, and a partial reduction of hematite to magnetite occurs at a temperature of 900°C and above.
In this regard, the magnetic properties of the oxide with weak ferromagnetism change with an increase in the SPS temperature, an increase in saturation magnetization is observed due to the formation of the Fe3O4 magnetic oxide phase, as well as a decrease in the coercive force due to active grain growth in the resulting ceramics.
Densification and properties of bulk nanocrystalline functional ceramics with grain size below 50nm.
An active grain growth is observed with an increase in the SPS temperature, and a partial reduction of hematite to magnetite occurs at a temperature of 900°C and above.
In this regard, the magnetic properties of the oxide with weak ferromagnetism change with an increase in the SPS temperature, an increase in saturation magnetization is observed due to the formation of the Fe3O4 magnetic oxide phase, as well as a decrease in the coercive force due to active grain growth in the resulting ceramics.
Densification and properties of bulk nanocrystalline functional ceramics with grain size below 50nm.
Online since: February 2023
Authors: Mosbah Daamouche, Djamaleddine Guitoume
Introduction
During the last years, titanium dioxide TiO2 had been the subject of an increasing number of studies due to its interesting properties such as: chemical stability, non toxicity [1], low cost and biocompatibility [2].
Furthermore, the obtained results revealed that the band gap of the prepared TiO2 films could be tuned by just varying the number of coatings.
Grain size, a, c and c/a values of TiO2 films with different thicknesses Number of coatings Thickness [nm] Grain size [nm] a [Å] c [Å] c/a 1 55 15 - - - 2 115 17 3.774 9.462 2.507 3 192 15 3.770 9.466 2.511 4 290 16 3.780 9.471 2.506 It is worthy to note that the value of c increases with thickness increase, the ratio c/a does not vary much with thickness variation, and the c/a value of the films with three layers is the closest to the bulk value [28].
For 300 °C, a very low number of grains are present while a dense granular morphology is seen for 500 °C.
The thickness of the layers increased with the number of coatings and varied from 55 nm (one coating) to 292 nm (four coatings).
Furthermore, the obtained results revealed that the band gap of the prepared TiO2 films could be tuned by just varying the number of coatings.
Grain size, a, c and c/a values of TiO2 films with different thicknesses Number of coatings Thickness [nm] Grain size [nm] a [Å] c [Å] c/a 1 55 15 - - - 2 115 17 3.774 9.462 2.507 3 192 15 3.770 9.466 2.511 4 290 16 3.780 9.471 2.506 It is worthy to note that the value of c increases with thickness increase, the ratio c/a does not vary much with thickness variation, and the c/a value of the films with three layers is the closest to the bulk value [28].
For 300 °C, a very low number of grains are present while a dense granular morphology is seen for 500 °C.
The thickness of the layers increased with the number of coatings and varied from 55 nm (one coating) to 292 nm (four coatings).
Online since: September 2012
Authors: Na Na Gong, Hai Yan Wu
Centroid location is a range-free and coarse-grained algorithm for outdoor.
(2) Amount of computation: To note the number of beacon nodes k doesn’t increase the amount of computation.
When the number of beacon nodes increases, the AE decreases(Fig.7).
Because of the cumulative errors, when the number of unknown nodes increases, the AE increases(Fig. 8).
AE with increasing number of beacon nodes(radio range=25) Figure 8.
(2) Amount of computation: To note the number of beacon nodes k doesn’t increase the amount of computation.
When the number of beacon nodes increases, the AE decreases(Fig.7).
Because of the cumulative errors, when the number of unknown nodes increases, the AE increases(Fig. 8).
AE with increasing number of beacon nodes(radio range=25) Figure 8.
Online since: March 2020
Authors: Yasuji Shimizu, Takashi Uno, Fuminori Sugaya, Takushi Toyooka, Katsuro Shimizu
Introduction
A large number of triangle-rimmed deity and beast mirrors were buried alongside people as personal belongings in early Kofun burial mounds, and a large number made from the same mold have been excavated.
A number of mirror molds from the Former Han Period (between 206 B.C. and 8 A.D.) have been excavated from Linzi District in Shandong Province, China.
These examples mainly include grass-blade pattern mirrors that were produced from strong clay molds mistaken for stone using uniform, relatively fine-grained real clay taken from the outside part of the mold onto the mold face.
This paper was written with support from a number of individuals and organizations to whom I would like to express my deepest gratitude.
[4] Numerals in brackets following “triangle-rimmed deity and beast mirror” are catalog numbers and correspond to the Triangle-Rimmed Deity and Beast Mirror Research Encyclopedia.” [5] [5] Shimogaki,H.
A number of mirror molds from the Former Han Period (between 206 B.C. and 8 A.D.) have been excavated from Linzi District in Shandong Province, China.
These examples mainly include grass-blade pattern mirrors that were produced from strong clay molds mistaken for stone using uniform, relatively fine-grained real clay taken from the outside part of the mold onto the mold face.
This paper was written with support from a number of individuals and organizations to whom I would like to express my deepest gratitude.
[4] Numerals in brackets following “triangle-rimmed deity and beast mirror” are catalog numbers and correspond to the Triangle-Rimmed Deity and Beast Mirror Research Encyclopedia.” [5] [5] Shimogaki,H.
Online since: February 2012
Authors: Elisabetta Ceretti, Claudio Giardini, Michela Longo, Gianluca Danilo D'Urso
In fact, the stirring phenomenon and the friction acting between the shoulder of the pin and the sheets, greatly increase the part temperature so that the material significantly changes its structural characteristics due to softening effect: grain dimensions, local hardness, grain orientation.
Many studies conducted on FSW of aluminum alloys show that a number of process parameters can affect the welding conditions and the weld properties [3].
Basing on the large number of microhardness data collected during the experimental campaign, the evaluation of the FEM model was mainly concentrated on the analysis of the material softening.
Many studies conducted on FSW of aluminum alloys show that a number of process parameters can affect the welding conditions and the weld properties [3].
Basing on the large number of microhardness data collected during the experimental campaign, the evaluation of the FEM model was mainly concentrated on the analysis of the material softening.
Online since: February 2012
Authors: Xuan Zhou, De Zhen Yang, Lin Lin Liu, Yi Ren
The definition of three-A general monitoring elements system.
1) Time dimension
Time dimension refers that each technical condition can be made as a unit to conduct fine-grained monitoring.
In the paper, each technical condition is made as a unit conducting fine-grained division in order to realize dynamic espial.
The number of property elements in this dimension can be changed based on the monitoring requirements.
The quantifiable requirements refers that the qualitative requirements are reflected via the quantitative data, such as the simplified design of circuit board which could be assessed by the statistics and analysis of the number of components.
And there are a number of technical conditions in each phase.
In the paper, each technical condition is made as a unit conducting fine-grained division in order to realize dynamic espial.
The number of property elements in this dimension can be changed based on the monitoring requirements.
The quantifiable requirements refers that the qualitative requirements are reflected via the quantitative data, such as the simplified design of circuit board which could be assessed by the statistics and analysis of the number of components.
And there are a number of technical conditions in each phase.