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Online since: October 2013
Authors: Krzysztof Dragan, Tadeusz Stepinski, Tadeusz Uhl, Michal Dziendzikowski
signal collecting
Remote Monitoring Unit
signal processing
sensor
self-diagnostic
tools
data classification
Data
Storage
Unit
Graphical
User
Interface
PZT network
measuring
nodes
Figure 1: System block diagram.
The methods differs in the choice of the data separation measure, which is to be maximized.
The best Fisher’s predictor (Eq. 3) or their effective counterparts (Eq. 5) can be used for data classification.
The data before (left) and after filtering (right)
Figure 6: The best data separating Fisher’s predictors (left) and corresponding nearest neighbor classifier (right).
The methods differs in the choice of the data separation measure, which is to be maximized.
The best Fisher’s predictor (Eq. 3) or their effective counterparts (Eq. 5) can be used for data classification.
The data before (left) and after filtering (right)
Figure 6: The best data separating Fisher’s predictors (left) and corresponding nearest neighbor classifier (right).
Online since: August 2013
Authors: Cai Lian Hao, Deng Hua Yan, Wei Hua Xiao, Jun Yin
Technical framework for research on Water-loss and Soil-erosion Dominated Non-point Source Pollution in Agriculture
Technical framework for research on water-loss-and-soil-erosion dominated non-point source pollution in agriculture shall cover three different layers: outfit of fundamental information, mechanism identification and evaluation, scheme setting and working out the countermeasures, and with details as followed(Fig. 3):
Layer for outfit of fundamental information: the way of taking regional meteorological data, soil data, hydrologic data, water quality data and some graphic materials as working database would facilitate the operation and validation to the simulation platform for regional non-point source pollution in agriculture.
At moment, there are many non-point source pollution models, domestically and globally, but the distributive physical non-point source pollution models, in absolute term, would be in need of considerable amount of fundamental data as in hydrology, meteorology, soil and water quality, etc., which is not suitable for application in actual practice whereas, a empirical model is not advantageous in forecasting/prediction and watershed management, due to its lack of description of working mechanism.
Except for effectiveness of input data and estimate of model parameters, model structure is also the key factor for forecast accuracy of model[22] whereas, in view of the fact that structures for varied non-point source pollution are different in many ways, it would be then differed in terms of adaptability to varied time scale, simulation capability in the course of hydrologic process, computational capacity against a variety of pollution load and performance in describing the courses of pollutants migration, etc[23]; and rather, these models appertaining to mechanisms, for the most parts, are being developed by the advanced countries, in so far as the model parameters and mechanism are not necessarily suitable for all other countries and regions[24].
Comparing water quality over land surface with water-environmental capacity of corresponding pollutants, carry out a review of the river-entry reduction or remaining water-environmental capacity.
For this reason, river-entry reduction or remaining water-environmental capacity acquired by computation must be translated into reduction volume of catchment-area pollutants discharge or remaining volume.
At moment, there are many non-point source pollution models, domestically and globally, but the distributive physical non-point source pollution models, in absolute term, would be in need of considerable amount of fundamental data as in hydrology, meteorology, soil and water quality, etc., which is not suitable for application in actual practice whereas, a empirical model is not advantageous in forecasting/prediction and watershed management, due to its lack of description of working mechanism.
Except for effectiveness of input data and estimate of model parameters, model structure is also the key factor for forecast accuracy of model[22] whereas, in view of the fact that structures for varied non-point source pollution are different in many ways, it would be then differed in terms of adaptability to varied time scale, simulation capability in the course of hydrologic process, computational capacity against a variety of pollution load and performance in describing the courses of pollutants migration, etc[23]; and rather, these models appertaining to mechanisms, for the most parts, are being developed by the advanced countries, in so far as the model parameters and mechanism are not necessarily suitable for all other countries and regions[24].
Comparing water quality over land surface with water-environmental capacity of corresponding pollutants, carry out a review of the river-entry reduction or remaining water-environmental capacity.
For this reason, river-entry reduction or remaining water-environmental capacity acquired by computation must be translated into reduction volume of catchment-area pollutants discharge or remaining volume.
Online since: September 2013
Authors: Jian Guo Wang, You Ye Zheng, Shun Bao Gao
In order to analyze deposits model, the methods adopted includes that arrangement of existing geophysical and geochemical exploration results, familiar with the former research results, and based on the collection of data, studying comprehensively the geological characteristics of deposits, discussing the deposits genesis.
It found that metal mineral combination about the Cu(Au) ore body is pyrite + chalcopyrite + molybdenite(less) + magnetite (less), and transit to a peripheral area of pyrite + chalcopyrite + magnetite, to sphalerite + chalcopyrite + pyrite + lead ore (less) from inside to outside in porphyries body in Xiongcun by studying, which reflected the rock permeability and diffusion about the hydrothermal system of ore-bearing porphyry, all this caused by different types of mineralization process due to temperature and pressure reduction.
Deficiency is a lack of data, it is very difficult to distinguish which kind of exploration method played a key role, the division includes both the exploration methods and working train of thought, prospecting cognition.
Research methods: ①arrangement of existing geophysical and geochemical exploration results, familiar with the former research results. based on the collection of data, studying comprehensively the geological characteristics of deposits, methods adopted the field observation and indoor optical slice identification, studying synthetically geological features in the area, which including the regional geological background, the ore types, ore fabric and material composition, metallogenic elements combination, and Wall rock alteration characteristics, and so on. ③ studying and discussing the deposits genesis about Xiongcun Cu (Au) deposits, summarizing metallogenic regularity and Prospecting model.
It is divided into 6 categories: ①Geological mapping method (77%).②Geochemical methods (69%).③geophysical method (47%).④theory model of prospecting method (24%).⑤Remote sensing method (12%).⑥Drilling method (11%). the newly discovered deposits in main metallogenic belt in Tibet since the geology survey beginning (1999) that It is difficult to completely identify which kinds of exploration methods played a key role due to the lack of systematic data.
It found that metal mineral combination about the Cu(Au) ore body is pyrite + chalcopyrite + molybdenite(less) + magnetite (less), and transit to a peripheral area of pyrite + chalcopyrite + magnetite, to sphalerite + chalcopyrite + pyrite + lead ore (less) from inside to outside in porphyries body in Xiongcun by studying, which reflected the rock permeability and diffusion about the hydrothermal system of ore-bearing porphyry, all this caused by different types of mineralization process due to temperature and pressure reduction.
Deficiency is a lack of data, it is very difficult to distinguish which kind of exploration method played a key role, the division includes both the exploration methods and working train of thought, prospecting cognition.
Research methods: ①arrangement of existing geophysical and geochemical exploration results, familiar with the former research results. based on the collection of data, studying comprehensively the geological characteristics of deposits, methods adopted the field observation and indoor optical slice identification, studying synthetically geological features in the area, which including the regional geological background, the ore types, ore fabric and material composition, metallogenic elements combination, and Wall rock alteration characteristics, and so on. ③ studying and discussing the deposits genesis about Xiongcun Cu (Au) deposits, summarizing metallogenic regularity and Prospecting model.
It is divided into 6 categories: ①Geological mapping method (77%).②Geochemical methods (69%).③geophysical method (47%).④theory model of prospecting method (24%).⑤Remote sensing method (12%).⑥Drilling method (11%). the newly discovered deposits in main metallogenic belt in Tibet since the geology survey beginning (1999) that It is difficult to completely identify which kinds of exploration methods played a key role due to the lack of systematic data.
Online since: March 2019
Authors: Fu Zhen Xuan, Yu Hui Huang, Shan Tung Tu, Shu Xian Lin
However, the lacking of stress corrosion tests data for nuclear steam turbine low-pressure rotors produced and used in China greatly restricts the domestic development of stress corrosion research on nuclear steam turbines [2].
After experiments, the specimen were cleaned again and the area reduction of specimens was measured.
The results can be characterized by one or more parameters, including the area surrounded by the stress-strain curve, the fracture time and the area reduction and so on.
As a whole, the elongation (or total strain) of the three low-pressure rotor steels in corrosive environment is significantly lower than that in air with a reduction of about 12%.
And the results of area surrounded by stress-strain curves, fracture time and area reduction were recorded as kA, kT and kR, respectively, as presented in Table 3.
After experiments, the specimen were cleaned again and the area reduction of specimens was measured.
The results can be characterized by one or more parameters, including the area surrounded by the stress-strain curve, the fracture time and the area reduction and so on.
As a whole, the elongation (or total strain) of the three low-pressure rotor steels in corrosive environment is significantly lower than that in air with a reduction of about 12%.
And the results of area surrounded by stress-strain curves, fracture time and area reduction were recorded as kA, kT and kR, respectively, as presented in Table 3.
Online since: January 2013
Authors: Da Sai Wang, Ai Qing Liu
In order to reveal the the performance of full-length pre-stressed anchor bolts, and research the rock pressure behavior law, a combination method of FLAC3D and situ tests were presented, the conclusions were drawn as following: the prestress of full-length pre-stressed anchor bolt was approximately uniform distribution along the slow anchoring section of the rod, while in the fast anchoringthe segment showed a negative exponential or linear form of attenuation, and the bolt axial load was biggest in the neutral point; the neutral point of full-length pre-stressed anchor bolt move to deeper of the drill hole with the reduction of rock strength, while neutral point shifting deeper would accelerate the destruction of the anchorage zone in deep rock formations, deteriorating the anchoring effect. the methods of pre-grouting and grouting bolt (or cable)should be taken to improve the anchoring force.
Bolt neutral point in siltstone is 100mm from the bolt tail, indicating that the neutral point of the highly prestressed bolt moves deeply to the surrounding rock as the rock strength reduction.
The monitoring data of 1 # and 2 # anchor showes that the prestress of the full-length pre-stressed bolts is approximately uniform distribution along the slow anchoring section of the rod, while it showes a trend of gradual decay in the fast anchoring section.
(2) The position of neutral point of the highly prestressed bolt moves deeply to the surrounding rock as the rock strength reduction, and the neutral point moving deeply will accelerate the destruction of the deep rock in the anchorage zone
Bolt neutral point in siltstone is 100mm from the bolt tail, indicating that the neutral point of the highly prestressed bolt moves deeply to the surrounding rock as the rock strength reduction.
The monitoring data of 1 # and 2 # anchor showes that the prestress of the full-length pre-stressed bolts is approximately uniform distribution along the slow anchoring section of the rod, while it showes a trend of gradual decay in the fast anchoring section.
(2) The position of neutral point of the highly prestressed bolt moves deeply to the surrounding rock as the rock strength reduction, and the neutral point moving deeply will accelerate the destruction of the deep rock in the anchorage zone
Online since: February 2013
Authors: Ke She Wang, Da Xian Hao, Chu Liang Zha, Yong Zhang, Hai Feng Yan
The article summarized the ball screw causes of the vibration, noise, comprehensive both at home and abroad research results to the ball screw vibration and noise generating mechanism .Then pointed out that the ball screw noise generation is the main reason of the screw groove waveness arouses nut forced vibration.Introduced the latest progress of the ball screw drive system modeling and the vibration model analysis,specific introduces several methods of reducing vibration and noise reduction.
Antivibration and Noise Reduction Method (1) Improve the precision of the ball screw The ball screw precision shortage is the most important factor in the reason of generates noise, and inevitable happened in the mechanical processing.
For the selected ball screws, have data show that the noise level is in proportion with dN values (d is ball rail center diameter, N is rotation number) of the logarithm, so we should the choice the lower value of the dN.
(6) Other noise reduction measures Mainly includes to ball nuts surrounding configuration noise casing; Outside of intubations fixed high strength engineering plastic and will guide bead tube covered completely exposed portion; In the ball screw shaft trip ends configuration buffer shock absorbers.
Antivibration and Noise Reduction Method (1) Improve the precision of the ball screw The ball screw precision shortage is the most important factor in the reason of generates noise, and inevitable happened in the mechanical processing.
For the selected ball screws, have data show that the noise level is in proportion with dN values (d is ball rail center diameter, N is rotation number) of the logarithm, so we should the choice the lower value of the dN.
(6) Other noise reduction measures Mainly includes to ball nuts surrounding configuration noise casing; Outside of intubations fixed high strength engineering plastic and will guide bead tube covered completely exposed portion; In the ball screw shaft trip ends configuration buffer shock absorbers.
Online since: May 2006
Authors: Joaquim M. Vieira, Filipe J. Oliveira, Maria Fátima Carrasco, Florinda M. Costa, João P. Araújo, Vitor S. Amaral, Mário S. Reis, D. Marinha, João Bessa Sousa
The reduction of Jc with the applied
magnetic field requires further improvements to reduce weak links.
These data show that the higher densification leads to higher values of Jc, due to higher density of pinning centers.
The magnetic field dependence of Jc is approximately exponential with field [9], and leads to a high reduction: For sample MB1-9, with highest Jc, 0.6x 10 6 A/cm2 at 0 Tesla, it reduces to 0.3x 10 6 A/cm 2 at 1 Tesla and to 0.11 x 10 6 A/cm2 at 2 Tesla.
This reduction is comparable to the one found in other studies and shows that improvements have still to be done in the materials processing in order to reduce the weak links.
These data show that the higher densification leads to higher values of Jc, due to higher density of pinning centers.
The magnetic field dependence of Jc is approximately exponential with field [9], and leads to a high reduction: For sample MB1-9, with highest Jc, 0.6x 10 6 A/cm2 at 0 Tesla, it reduces to 0.3x 10 6 A/cm 2 at 1 Tesla and to 0.11 x 10 6 A/cm2 at 2 Tesla.
This reduction is comparable to the one found in other studies and shows that improvements have still to be done in the materials processing in order to reduce the weak links.
Online since: October 2013
Authors: Jian Fei Sun, Xue Min Zhang, Jun Ling Zhao, Fu Wei Kang
The hot deformation behaviors of the nickel-base superalloy GH4169 have been studied by isothermal constant true strain rate compression testing at 950˚C-1150˚C, 0.01s-1-10s-1 and the height reduction 50%.
The processing maps of GH4169 alloy have been constructed at different strains on the basis of testing data using a dynamic materials modeling.
The specimens were compressed with height reduction of 50%, in isothermal condition at the temperature and strain rate ranges of 950˚C~1100˚Cand 0.01s-1~10s-1, respectively.
The processing maps of GH4169 alloy have been constructed at different strains on the basis of testing data using a dynamic materials modeling.
The specimens were compressed with height reduction of 50%, in isothermal condition at the temperature and strain rate ranges of 950˚C~1100˚Cand 0.01s-1~10s-1, respectively.
Online since: August 2011
Authors: Chang Sheng Wang, Hai Xiong Wang, Jiang Zhang, Ji Bin Li
Experimental data and basic technical parameters of the rolling process as shown in Table 2, Table 3, and Table 4
The 13th times too large deformation resistance is caused by a one-way winding tension, data processing, with due consideration of coiling tension.
However, curves obtained by data inspection prone to bias, but also for online use computer-controlled rolling process is extremely inconvenient.
This article is obtained through the hot spot specific data to create three types of aluminum alloy hot deformation resistance.
The calculated data from this mathematical model of deformation resistance are good agreement with result of the experiment.
The 13th times too large deformation resistance is caused by a one-way winding tension, data processing, with due consideration of coiling tension.
However, curves obtained by data inspection prone to bias, but also for online use computer-controlled rolling process is extremely inconvenient.
This article is obtained through the hot spot specific data to create three types of aluminum alloy hot deformation resistance.
The calculated data from this mathematical model of deformation resistance are good agreement with result of the experiment.
Online since: January 2012
Authors: Davide Rocchi, Salvatore Russo, Giosuè Boscato
The ambient response analysis of global structure and dome element enable to improve the FE model by model updating methodology using modal data.
The approach adopted for variation of these parameters has been incremental as regards the modulus of elasticity, the modal mass and boundary conditions, for the definition of the structural damping has been based on experimental data, see Table 2.
In the first set has been determined a common value to the whole structure; this data was modified locally through a second refinement to take account of the specificities of the various structural and architectural elements constituting the basilica.
The data obtained are shown in Table 5 and are shown in graphic form in Figure 20.
Ambient Vibration Data Analysis for Structural Identification and Global Condition Assessment.
The approach adopted for variation of these parameters has been incremental as regards the modulus of elasticity, the modal mass and boundary conditions, for the definition of the structural damping has been based on experimental data, see Table 2.
In the first set has been determined a common value to the whole structure; this data was modified locally through a second refinement to take account of the specificities of the various structural and architectural elements constituting the basilica.
The data obtained are shown in Table 5 and are shown in graphic form in Figure 20.
Ambient Vibration Data Analysis for Structural Identification and Global Condition Assessment.