Search results

Based on Eley-rideal mechanism,four major chemical reactions including the adsorption of ammonia, desorption of ammonia, selective catalytic reduction and oxidation of adsorbed ammonia are selected to study the SCR control strategy.
Combinedwith the equations of chemical reaction process,a mathematical model of SCR catalytic converteris established.To achieve a high NOX reduction efficiencyof SCR system, thereasonable and efficacious control strategies for the micro-element models of SCR catalytic is simulated,which including the feedback control strategy based on the feed-forward controller and the PID control strategy.
The problem how to constitute a reasonable control strategyis the main challenge of the SCR system, which is to achieve high NOX reduction which is over 80% and low ammonia slip that is less than 25ppm.
Table-1Simulation Data and Results The ratio of ammonia and nitrogen NOX,in=1000ppm NOX,in=1500ppm NOX,in=2000ppm Conversion rate (%) Conversion rate (%) Conversion rate (%) 0.45 82.97 84.85 85.29 0.75 83.07 84.45 85.39 1.05 83.01 84.65 85.39 The feedback and feed-forwardcontrol strategy.The ratio of CNOx,IIand CNH3,IIwasset to a fixed value as the feed-forward controller.
Table-2 Simulation Data and Results Amplification factor Nitrogen Oxide emissions 1000ppm NOx,out NH3,out mol/s ppm mol/s ppm 10 1.03e-3 203.43 1.01e-4 10.73 100 9.92e-4 195.92 1.07e-4 11.37 1000 7.42e-4 146.55 1.62e-4 17.21 Compared to the traditional SCR control strategy, this model can improve the control performance of SCR system with the dramatic changes of conditions in a certain extent.

To optimize the reduction technology, thermodynamics of SSI reduction was investigated.
Reduction of SSI Spherical Sponge Iron (SSI) with 1~5 mm diameter was prepared through the process of palletizing, roasting and direct reduction by H2.
lnr=ln(-dC/dt)=lnkobs+nlnC (3) According to the kinetic experiment datum in Fig. 2, reaction rate equations of SSI reduction by hydrogen could be calculated and illustrated in Table 1.
Activity energy of SSI reduction.
To optimize the reduction technology, the activity energy of SSI reduction was calculated according to the weight loss curve in this paper.

Hyperspectral data is endowed with characteristics of intrinsic nonlinear structure and high dimension.
The linear dimension reduction methods always depend on a linear projection which maps the input data into the space spaned by the most significant eigenvectors of the covariance matrix.
Let be the test sample set and be the reference data set.
In the RX algorithm, only the data covariance matrix is required without any additional posteriori information.
Experimental data in this section is an OMIS image with 124 bands.

The system uses embedded intelligent control instrument to do digital acquisition of various heat treatment parameters, the embedded intelligent control software for data processing, distributed intelligent control, and data transmission through the communication network.
RFID writes the data processing management information to database after each production link.
Connection between Kingview and SQL SEVER first need to configure ODBC data source in PC machine.
Records should be relative to the corresponding form field of remote database, so that we can through the SQL statement correctly query the database table data and the correctly inserts data into the corresponding form.
Differing from the traditional ERP system, the main characteristic of system is real-time monitoring the process parameters, production process, equipment and operator states, and realized the data sharing between systems.

Data sources.
Data of this study obtained from a survey of 119 farmers from 6 production teams across the entire Shuanghe Farm during the summer of 2013.
Furthermore, data processing and analysis were completed by SPSS17.0 and Excel 2007.
We sincerely thank participating colleagues (Xinghua Zhu )and farmers for their assistance and cooperation during data collection.
Carbon footprint of China's crop production—An estimation using agro-statistics data over 1993–2007.

Saiang’s group has gotten valuable monitoring data by microseimic tests and conducted study on mechanical response of EDZ around shallow tunnel in brittle rock by assuming deformation modulus distributes linearly along radius from excavation surface, as shown in Fig.3.
Fig. 1 Regular partition and uniform reduction method Fig. 2 Regular partition and linear reduction method Irregular partition and uniform reduction method.
Irregular partition and uniform reduction method is to determine EDZ’s zones by numerical calculation or curve-fitting based on field tests data, such as deformation, acoustic velocity, and then, in every zone the parameters are uniformly reduced, as shown in Fig.4.
Whatever regular or irregular partition, mechanical parameter reduction is determined according to engineering analogy or limited local monitoring data, which is experience dependent and of uncertainty due to researcher’s engineering experience and knowledge.
Thus, monitoring data needs to be effectively and generally used and analyzed to find certain macro relationship between outer characteristics and inner mechanism of excavation response, and then establish a model to connect determinations of scope and parameter reduction of EDZ.

The basic idea behind this sort of approaches is to approximate the matrix derived from the noisy data, with another matrix of lower rank from which the reconstructed signal is derived.
Equation (6) can be rewritten as (7) Comparing (3) and (7) yields (8) and (9) Since the matrices and are respectively the approximation of the initial clean data matrix and the noise matrix, we can reduce the effect of additive noise from the original signal via removing or decreasing the subspace and utilizing the matrix in reconstruction of the enhanced data matrix.
In this method a polynomial is fit to a number of consecutive data points from the time-series.
They include the number of rows in the Hankel data matrix “1”, the optimum threshold point needed for space subdivision “”, the degree of polynomial , “”and the window size of the Savitzky-Golay filter “” used for filtering the singular vectors.
In the traditional SVD and GSVD approaches, the singular values of the data matrix are filtered for speech enhancement, while the singular vectors of the noisy data matrix are not enhanced.

We demonstrate significant reduction in periodicity achieved with Wang tiling (compared to the periodic synthesis) in both the microstructures and results of numerical simulations.
As a results, a significant reduction in spurious periodic artefacts in reconstructed microstructure realizations is achieved, compared to the PUC based reconstruction [1, 2].
Spatial statistics In order to validate the hypothesis of reduction of periodicity in the system and the related DEM calculations, we employ the following spatial descriptors chosen with emphasis on their sensitivity to intrinsic correlations.
In order to exploit FFT efficiency, the values are attributed to the nearest point in the regular grid and the convolution of data is calculated.
The only difference to S2 is that the data are not of boolean type.

Since the influential factors of vacuum reduction of condenser are fuzzy and uncertain, the improved FAHP is used.
We can build a condenser vacuum reduction factors set and fault symptoms set [4].
So can establish a condenser vacuum reduction factors hierarchical analysis system.
The following is the test data: unit loads 600 MW, the exhaust steam temperature of low back pressure condenser dropping from 44℃ to 37℃, the vacuum degree rising from 93kPa to 95.6kPa, the coal consumption dropping from 240 t/h to 231 t/h.
For the failure instance in paper, the final result is "the reduction or interruption of the water pump seal water".

Cathode research in DMFC technology is mainly focused on developing more selective and methanol-tolerant catalysts for oxygen reduction.
These catalysts were electrochemically tested for their activity towards methanol oxidation and oxygen reduction in a half cell arrangement.
Completing reduction of the precursor, nitrogen gas was streamed in order to remove hydrogen.
Several standard composites were prepared by same method from general precursor for comparison of data.
As shown in Fig.2, these data indicate that PtTm-C is less active toward O2 reduction than Pt-C.