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Online since: October 2014
Authors: Guo Qiang Liu, Jiu Peng Zhang, Peng Zhi Wang
And the reduction amplitude of noise increases with vehicular acceleration.
And the exposed-aggregate cement concrete plate is casted in rutting plate mold (30cm×30cm×5cm), then testing the BPN and TD and recording the data.
It is more persuasive to apply parallel tests for each speed and collect 3~4 sets of data.
And the reduction amplitude of noise increases with vehicular acceleration.
And the reduction amplitude of noise increases with vehicular acceleration.
And the exposed-aggregate cement concrete plate is casted in rutting plate mold (30cm×30cm×5cm), then testing the BPN and TD and recording the data.
It is more persuasive to apply parallel tests for each speed and collect 3~4 sets of data.
And the reduction amplitude of noise increases with vehicular acceleration.
And the reduction amplitude of noise increases with vehicular acceleration.
Online since: August 2018
Authors: Kyoung Woo Kim, Hye Kyung Shin, Jin Yun Chung, Jong-Young Park
This study investigated the characteristics of reduction in vibration and floor impact sound in apartments where the bubble deck slab was applied.
The two slabs showed a nearly similar pattern of reduction characteristics with regard to heavyweight impact sound.
The bubble deck slab showed a better vibration reduction at the low frequency domains than that of the solid slab as the vibration level was lower at 80Hz or lower.
The comparison and measurement results were based on the limited measured data.
Thus, performance improvements are needed in the future through the use of more data and correlation analysis.
The two slabs showed a nearly similar pattern of reduction characteristics with regard to heavyweight impact sound.
The bubble deck slab showed a better vibration reduction at the low frequency domains than that of the solid slab as the vibration level was lower at 80Hz or lower.
The comparison and measurement results were based on the limited measured data.
Thus, performance improvements are needed in the future through the use of more data and correlation analysis.
Online since: November 2012
Authors: Dan Ying Gao, Ming Zhang
Compared with reinforced concrete beam without steel fiber, beams joined steel fiber can effectively reduce the crack width, the reduction of steel fiber reinforced concrete beams crack width are 52%~ 121% under different fatigue cycles.
In the Fig. 3b, it is shown that beams with end-hook steel fiber got the most remarkable effect, the reduction of fatigue crack width are 38%~110% compared with other two types of steel fiber.
The reduction of maximum crack width are 26%~87% following with the range growth of the steel fiber adding.
For simplified calculation the formula of crack spacing can be written as: (8) k is the fatigue crack spacing coefficient considering the influence of steel fiber, according to the analysis of the test data in this paper: k=0.78.
(9) Because reduction coefficient of tensile stress of concrete qf and amplifying coefficient of tensile stress of steel hf are all probably relative to Fatigue cycles (N), setting ,,the calculation formula for fatigue crack width can be written as: (10) Considering the linking up with the current ordinary concrete structures and steel fiber concrete component calculation formula, and for convenient calculation, according to calculation model, the calculation formula for crack width of steel fiber high-strength concrete beams is simplified as: (11) In the formula, n is the comprehensive correction factor for fatigue crack width of steel fiber reinforced high-strength concrete beams, according to the test data by regression analysis , n=1.4,a=-1.2518, b=0.5458; wmax is the maximum crack width not considering the effect of steel fiber, lf is the represent
In the Fig. 3b, it is shown that beams with end-hook steel fiber got the most remarkable effect, the reduction of fatigue crack width are 38%~110% compared with other two types of steel fiber.
The reduction of maximum crack width are 26%~87% following with the range growth of the steel fiber adding.
For simplified calculation the formula of crack spacing can be written as: (8) k is the fatigue crack spacing coefficient considering the influence of steel fiber, according to the analysis of the test data in this paper: k=0.78.
(9) Because reduction coefficient of tensile stress of concrete qf and amplifying coefficient of tensile stress of steel hf are all probably relative to Fatigue cycles (N), setting ,,the calculation formula for fatigue crack width can be written as: (10) Considering the linking up with the current ordinary concrete structures and steel fiber concrete component calculation formula, and for convenient calculation, according to calculation model, the calculation formula for crack width of steel fiber high-strength concrete beams is simplified as: (11) In the formula, n is the comprehensive correction factor for fatigue crack width of steel fiber reinforced high-strength concrete beams, according to the test data by regression analysis , n=1.4,a=-1.2518, b=0.5458; wmax is the maximum crack width not considering the effect of steel fiber, lf is the represent
Online since: June 2014
Authors: Tian Tian Gan, Ke Qi Wu, Ji Meng Tang
Method and Data Estimation
A benefit-cost analysis method is used in this paper, and the costs and benefits considered for an intercity railway are concluded in Table 1.
Costs and benefits considered Costs Benefits Infrastructure (I) Rolling Stock (S) Operation (O) Infrastructure maintenance (M) Residual value (R) Time saving (TS) from other modes Cost reduction (CR) in alternative modes Reduction of external costs (REC) in: Energy consumption and emissions The paper takes Beijing-Tianjin Intercity Railway as an example.
Reduction costs of Energy consumption and emissions are mainly considered in this part.
Energy consumption of railway is 83.05% lower than highway (see Table 3).The transfer demand from highway to intercity railway should be measured as reduction of energy consumption, assuming that the energy consumption of national railway and intercity railway is similar.
Modes Before After 2007 2008 2009 2010 Car and bus 29.42 28.05 30.01 31.04 National railway 20.23 19.70 16.37 17.38 Intercity railway ----- 4.23 9.79 11.83 Total 49.65 51.98 56.17 60.25 Source: data from statistics and reports of railway design department.
Costs and benefits considered Costs Benefits Infrastructure (I) Rolling Stock (S) Operation (O) Infrastructure maintenance (M) Residual value (R) Time saving (TS) from other modes Cost reduction (CR) in alternative modes Reduction of external costs (REC) in: Energy consumption and emissions The paper takes Beijing-Tianjin Intercity Railway as an example.
Reduction costs of Energy consumption and emissions are mainly considered in this part.
Energy consumption of railway is 83.05% lower than highway (see Table 3).The transfer demand from highway to intercity railway should be measured as reduction of energy consumption, assuming that the energy consumption of national railway and intercity railway is similar.
Modes Before After 2007 2008 2009 2010 Car and bus 29.42 28.05 30.01 31.04 National railway 20.23 19.70 16.37 17.38 Intercity railway ----- 4.23 9.79 11.83 Total 49.65 51.98 56.17 60.25 Source: data from statistics and reports of railway design department.
Online since: September 2016
Authors: Boris Ovechkin, Viktor Sergeev, Vasilii Naidfeld, Sergey Panin, Ilya Vlasov, Pavlo Maruschak
According to the data of pyrometric monitoring during the treatment the surface layer of the specimens experienced a short-term heating up to temperature of 600...900 °C.
As is known from pyrometer measurement data this layer experienced short term heating up to the temperature of 900° C that can give rise to grain growth.
This agrees well with metallography data (Fig. 1b, c).
According to the testing data the fatigue life-time of specimens under cyclic alternating bending is also increased due to the modification of surface layer by ~ 2 times.
It is manifested primarily in reduction of the average rate of shear strain.
As is known from pyrometer measurement data this layer experienced short term heating up to the temperature of 900° C that can give rise to grain growth.
This agrees well with metallography data (Fig. 1b, c).
According to the testing data the fatigue life-time of specimens under cyclic alternating bending is also increased due to the modification of surface layer by ~ 2 times.
It is manifested primarily in reduction of the average rate of shear strain.
Online since: October 2016
Authors: Toshiki Hirogaki, Takakazu Ikegami, Eiichhi Aoyama
Since the DDM has no reduction gears, it can be presumed that it is easier to estimate the condition, such as inertia and resonance frequency of a workpiece on a table, by using the servo data of the electric current flowing through the DDM than a motor with reduction gears.
The present angular acceleration is calculated by the position data from the rotary encoder employed for a DDM.
Therefore resonance frequency can be measured more accurately from the position data of the rotary encoder.
(2) It is found to be effective for improving kinematic performance of rotary axes to introduce the method of estimating the inertia of a rotary axis by using the servo data obtained form the DDM.
Since the DDM has no reduction gears, more accurate date can be obtained from it and inertia of a rotary axis is estimated more accurately than a motor which has reduction gears.
The present angular acceleration is calculated by the position data from the rotary encoder employed for a DDM.
Therefore resonance frequency can be measured more accurately from the position data of the rotary encoder.
(2) It is found to be effective for improving kinematic performance of rotary axes to introduce the method of estimating the inertia of a rotary axis by using the servo data obtained form the DDM.
Since the DDM has no reduction gears, more accurate date can be obtained from it and inertia of a rotary axis is estimated more accurately than a motor which has reduction gears.
Online since: December 2012
Authors: De Jun Li, Hao Fang
Data acquisition system
According to the requirements of power department, the installation of a set of power generation and environmental monitoring equipment(is shown in Fig.1 )is stalled at Technology park, its composition including: power data acquisition system, environmental index acquisition system (temperature and humidity, wind direction, irradiation degree)[3] . for the analogue signal that get from the systems are switched into digital signal by the A/D converter, being connected to WINCC by the 485 bus and being saved, and Query the data that collected by Each sensor by Data query software in real-time.
The system data from inverter boot began gathering at 6:30, to inverter shutdown over at 18:30.
Power data are recorded by every 30s, environmental data are recorded once every 5 minutes, the daily capacity get from accumulation of the real-time duration .
Annual accumulative quantity that instead of the conventional energy quantity: (1) =31.30 TON(Standard Coal Equivalent) Among them, W = 4217.14 MJ/ M2 is solar radiation quantity throughout the year for Wuhan area, Ac is Mono-si silicon and polycrystalline silicon PV power system components area.[4] One year time all the data analysis of the power station 4.1 power data analysis Getting A-si cells cumulative capacity from the data of power generation that collected throughout the year by Data acquisition system is 337813 kWh, Mono-si PV modules accumulative capacity is 303895kWp Among it, including the daily average polycrystalline system capacity of925.51 kWh, the daily average capacity of Mono-si silicon system is 832.58kWp.
The Fig.3(b) is China international exchange stand daily radiation data set from October.2010 to October.2011.
The system data from inverter boot began gathering at 6:30, to inverter shutdown over at 18:30.
Power data are recorded by every 30s, environmental data are recorded once every 5 minutes, the daily capacity get from accumulation of the real-time duration .
Annual accumulative quantity that instead of the conventional energy quantity: (1) =31.30 TON(Standard Coal Equivalent) Among them, W = 4217.14 MJ/ M2 is solar radiation quantity throughout the year for Wuhan area, Ac is Mono-si silicon and polycrystalline silicon PV power system components area.[4] One year time all the data analysis of the power station 4.1 power data analysis Getting A-si cells cumulative capacity from the data of power generation that collected throughout the year by Data acquisition system is 337813 kWh, Mono-si PV modules accumulative capacity is 303895kWp Among it, including the daily average polycrystalline system capacity of925.51 kWh, the daily average capacity of Mono-si silicon system is 832.58kWp.
The Fig.3(b) is China international exchange stand daily radiation data set from October.2010 to October.2011.
Online since: June 2020
Authors: Nurul Syuhadah Khusaini, Nurul Hayati Abdul Halim, Qhairunisha Mohd Khalid, Nor Hayati Saad
The aim of Rasch analysis is to find the extent to which observed rating scale data satisfy the measurement [14].
A preliminary study was done to gather all the data on the current practice at Company X.
Data for analysis is captured from both the IATF 16949 and TPS internal audit checklist.
Data for both internal audit checklists were collected from the internal audit checklist at the same production plant.
The comparison is important for reasonable and practical data.
A preliminary study was done to gather all the data on the current practice at Company X.
Data for analysis is captured from both the IATF 16949 and TPS internal audit checklist.
Data for both internal audit checklists were collected from the internal audit checklist at the same production plant.
The comparison is important for reasonable and practical data.
Online since: February 2013
Authors: Yun Wu, Xian Ming Zhang
Base on the observation, fitted for average of repeated experimental data by quadratic function and linear function, respectively.
According to previous experimental data from research team, the average concentration of ammonia nitrogen was about 0.826g.L-1[11], K1 should take 45.063 according to literature[14].
According to our previous experimental data [11], the average concentration of ammonia nitrogen 1.446g.L-1, pH in methanogenic phase was 7.
The test results showed the significance test statistic F of the first group data and the second group data from single-phase anaerobic digestion experiment were 386.22 and 268.63, respectively.
The significance test statistic F of the first group data and the second group data from two-phase anaerobic digestion experiment were 421.69 and 372.56, respectively.
According to previous experimental data from research team, the average concentration of ammonia nitrogen was about 0.826g.L-1[11], K1 should take 45.063 according to literature[14].
According to our previous experimental data [11], the average concentration of ammonia nitrogen 1.446g.L-1, pH in methanogenic phase was 7.
The test results showed the significance test statistic F of the first group data and the second group data from single-phase anaerobic digestion experiment were 386.22 and 268.63, respectively.
The significance test statistic F of the first group data and the second group data from two-phase anaerobic digestion experiment were 421.69 and 372.56, respectively.
Online since: June 2010
Authors: Soon Jong Yoon, So Young Park, Seung Cheol Baek, Hyo Jin Kim, Hoon Choi
Table 2 The average of rebound hardness (R) in each measuring point
Measuring point No. 1 No. 2 No. 3 No. 4 No. 5
Average of R 58.5 60.8 50 56.7 61.3
' 2
9.37 (0.987) (1.3 109)( / )
t
ckf R t kgf cm
= ⋅ ⋅ + − (2)
Strength Reduction Factor.
The equation for the coefficient e3 considering the impact of changes in strength reduction factor recommended by ACI 318-02 is given as Eq. 3 [3].
Table 3 The strength reduction factor (φ) by year year 1995 1999 2002 2005 Strength reduction factor (φ) 0.70 0.70 0.65 0.65 3 07 /e φ φ= (3) 07φ is the strength reduction factor in 2007 and φ is the strength reduction factor by year.
In the safety evaluation, 29.43MPa of the compressive strength and 4.20MPa of the tensile strength are adopted from the design data [4].
The equation for the coefficient e3 considering the impact of changes in strength reduction factor recommended by ACI 318-02 is given as Eq. 3 [3].
Table 3 The strength reduction factor (φ) by year year 1995 1999 2002 2005 Strength reduction factor (φ) 0.70 0.70 0.65 0.65 3 07 /e φ φ= (3) 07φ is the strength reduction factor in 2007 and φ is the strength reduction factor by year.
In the safety evaluation, 29.43MPa of the compressive strength and 4.20MPa of the tensile strength are adopted from the design data [4].