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In this study, land use data in the Mianzhu city, China are extracted from remote sensing data of 1970s, 1980s, 1995, 2000 and 2005 and land use atlas are established and analyzed using geo-information atlas theory. The results indicate that from the temporal series, farmland and unused land decrease and other lands increase during 1970s to 2005 except farmland increases and forest land reduces in...
The existence of mixed pixels in satellite images, especially those with coarse resolution, is still a challenge for crop planting area extraction with traditional classification methods. In this study, taking Henan Province as the pilot area, N_FINDR algorithm was used for automatic determination of spectral endmembers, and then Linear Mixing Model was utilized for mixed pixels decomposition to derive...
Being one of the important factors responsible for image quality, the band to band registration error (BBR error) of high resolution imagery affects considerably the application precision of remote sensing. The author analyzed the influence of BBR error on remote sensing application in such aspects as vision effects, supervised classification based on pixel, object-oriented imagery interpretation...
Measurement matrix design plays a very important role in the whole process of compressed sensing, for it determines the possibility of the signal compression and the receiver accuracy of the original signal reconstruction. This paper proposes an improved method to construct Hadamard measurement matrix after adequate study of compressed sensing. Simulation and verification is carried out and compared...
Organic Rankine Cycles are particularly suitable for recovering energy from low-grade heat sources. Scroll expander has all the advantages of a scroll machine and is suitable to be used in ORC system. As the key element of the ORC, its safe operation has a direct relationship with all the system. Based on deep research on scroll expander's working process, first the paper establishes dynamic mathematical...
A reaction model including NO reduction by reburning with pulverized coal and SO2 absorption by CaO is presented. It includes the coal combustion model, which covers coal devolatilisation, combustion of volatiles, and combustion of char. The NO conversion model by reburning includes the formation of NO from fuel nitrogen and the reduction of NO by hydrocarbon, HCN, NH3 as well as char. Sulfation of...
As a post-treatment technology, biological aerated filter (BAF) was taken to treat the micro-polluted refinery wastewater. When hydraulic retention time (HRT) was two hours, filler was ceramsite, and the inlet mode was down-flow, BAF obtained the optimum treatment effect. The introduction of polycyclic aromatic hydrocarbons (PAHs) degrading bacteria in BAF can improve the treatment effect for refinery...
Many excess sludge reduction technologies have already been researched. In this paper, we systematically estimate the following possible wastewater treatment technologies that may explain the reduction of excess sludge: completely mixed bioreactor, plug flow reactor and aerobic-settling-anaerobic (OSA) process. Results show that the mixed, plug-flow and OSA processes respectively produce excess sludge...
The synchronization based on active control strategy for different chaotic system is realized in order to solve the problem of sensitive dependence on initial conditions, and a square matrix for chaotic system states is also obtained by step-by-step operation of multi-elementary matrix transformation. Synchronous decryption of image can be realized because of the invertibility between decryption matrix...
Chinese word segmentation is a base, difficult and important problem in natural language processing. New word is a bottleneck to Chinese word segmentation. The query log of search engine contains user habits and behaviors. There are many popular words and professional terms in these logs. We present a new word extraction method, which uses the grammar rules and statistics information. The experiment...
Image hashing finds extensive applications in content authentication, database search. This paper develops a novel algorithm for generating an image hash based on contour let hidden Markov tree (HMT) model and SVD. The contour let transform is a new two-dimensional extension of the wavelet transform using multi scale and directional filter banks. It effectively captures smooth contours that are the...
Refining effluents from acrylonitrile manufacturing are very refractory to biodegradation. This paper evaluated the pollutant distribution characteristics of ANRE by means of multi scale membrane filtrations, including microfiltration (0.1 µm ∼ 1µm), 3-scale ultrafiltration (50 KD, 10 KD and 6 KD), nanofiltration and reverse osmosis. Laser particle size analyzer and nano particle size analyzer tests...
Power system islanding contingency has always been one of the most severe wide area system failures. The recent Hurricane Gustav landed in west coast in 2008 was one exact case to illuminate the importance and severity of this kind of contingencies. Longtime the researches of islanding situations focus on studying the coherence groups of the generations under an islanding contingency. In this paper,...
Carbon cycle of terrestrial ecosystem is one of the hot issues in global change science. And there are more difficult during study with agroecosystem because of the strong affect caused by human activities such as sowing, fertilizing and irrigation. In this study, a measurement is carried out in Guantao, Hebei Province, China, which is a typical argoecosystem station. In this paper, carbon dioxide...
In engineering practices, curve fitting is a common method to evaluate the performance of machines or equipments using the collected data. If the collected data works as a whole and can not be divided into groups, conventional curve fitting methods can be used to perform the task. Researchers have proposed some improved methods with higher precision and computational efficiency, in order to handle...
With the rapid growth of electricity grid and the unusually changing of global climate in recent years, the comprehensive analysis of the lightning parameters becomes very important. Sichuan Province started to use Lightning Location System (LLS) in 2003, it has been running for 7 years. The database has accumulated a lot of valuable lightning detection data about lightning activity. Comparing with...
A robust image hashing using locally linear embedding (LLE) is presented. The image is first rescaled to a fixed size. Then the image is divided into key-dependent overlapping blocks. Every blocks are reshaped to vectors and combined to the matrix. The LLE algorithm is applied to the matrix. The reconstruction weights coefficients reflect the intrinsic geometric properties of image and are invariant...
A servo-actuation system is one of the key executing subsystems of the flight control system of an aircraft. With the development of the fly-by-wire control systems, the redundant servo-actuation systems have been extensively applied. A servo-actuation system has a long life and high reliability, which results in the lack of experiment information. In the meantime, the available data is insufficient...
This paper deals with the analysis of fault current occurred in a power system including STS, PCS, and load, which are the part of a microgrid. In case of utility side short circuit fault a huge current may flow through a STS, which results in a severe power quality problem in the microgrid. Therefore, minimization of the fault current and STS breaking time is essential to obtain high power quality...
In order to solve uncertainty and time-varying problems of evaporator which is non-minimum phase object, direct self-tuning control based on generalized minimum variance method combined with the forgetting factor recursive least squares(FFRLS)parameter estimation is investigated in this paper. Firstly, self-tuning control has the ability to tune its own parameters. It is well suited for handling time-varying...
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