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Traditional power systems have become outdated, unable to provide the clean energy enforced by current regulations. In addition, the intermittent renewable energy and the distributed generation make it difficult for the current electricity grid to reliably respond to increased energy demands. For that, a heat and power integrated energy system (IES) can provide better results compared to individually...
The paper investigates vector quantization coding of high-order (e.g., 20th-50th order) linear prediction coding (LPC) parameters, and proposes a novel hierarchical decomposition vector quantization method for a scalable speech coding framework with variable orders of LPC analysis. Instead of vector quantizing the whole group of LPC parameters in the linear spectral frequency (LSF) domain directly,...
The Low-Voltage Ride-Through (LVRT) has become an important grid requirement for offshore wind farms connecting with Voltage Source Converter based High Voltage Direct Current (VSC-HVDC) links. In this paper, a cooperative control strategy with LVRT ability is proposed for a VSC-HVDC connected variable speed Squirrel-Cage Induction Generator (SCIG) wind farm. The approach employs a DC-link voltage...
In order to prevent long term voltage instability and induced cascading events, a load shedding strategy based on the sensitivity of relay operation margin to load powers is discussed and proposed in this paper. The operation margin of critical impedance backup relay is defined to identify the runtime emergent states of related system component. Based on sensitivity analysis between the relay operation...
Cognitive radio has been put forward to make efficient use of scarce radio frequency spectrum. Once available frequency bands have been detected using spectrum sensing algorithms, spectrum auction can be employed to allocate the detected available frequency bands to secondary users. In this paper, a bidding algorithm based on Q-learning for secondary users is proposed. Secondary users employ the proposed...
The risk assessment of drinking water source focused on quantitative assessment of contaminants detected in drinking water on human health risks, but the potential environmental risk assessment of source drinking water protection is rare research. Therefore, in this paper, expert systems and AHP were introduced into the conventional fuzzy comprehensive evaluation in order to improve the degree of...
Based on logarithmic mean Divisia index method I and II, the factors impacting the changes of Chinese industrial SO2 emission intensity are decomposed into SO2 production intensity effect, government control effect (policy effect) and industrial structural effect. Using data of 1998 to 2006, result shows that the main driver behind the reduction of SO2 emission intensity is SO2 production intensity,...
In numerous neuroscience studies, multichannel EEG data are often recorded over multiple trial periods under the same experimental condition. To date, little effort is aimed to learn spatial patterns from EEG data to account for trial-to-trial variability. In this paper, a hierarchical Bayesian framework is introduced to model inter-trial source variability while extracting common spatial patterns...
The volatility of stock price states the uncertainty of the future price movements, that is risk. By means of the ARCH and its modified models, this paper presents a verification analysis of the volatility heteroscedasticity and the resilience to external shocks for China stock market in the past three years based on the stock index of SSE180, SZSE40, Coal, Petroleum and Finance sectors. The study...
By means of the ARCH (Auto-regressive Conditional Heteroscedasticity) and its modified models, this paper presents an empirical analysis of the volatility heteroscedasticity and the resilience to external shocks for China emerging stock market in the past three years based on the stock index of SSE180, SZSE40, Coal/Petroleum and Finance sectors. The results show that the fluctuation of SSE180 index...
The stock prices are affected by historical information to a certain extent. The fluctuation volatility can be measured by the Hurst index. With modified rescale range/standard deviation (R/S) model, this paper presents an analysis of CSI 300 index, coal and oil industry index, and other six individual stocks in different industries for their fluctuation features.
In this paper, we propose a decentralized control strategy to dispatch and control the output power for wind farm. In this strategy, the power control system is supposed to operate as a virtual market place. Every wind generator is treated as a buyer agent or a seller agent. The buyer and seller agents cooperate and compete to process transactions for setting value of power. The market place manager...
In stock markets, the price is fluctuating around its average value with the time being. One of the volatilities is the variance heteroscedasticity. It is found that auto-regressive conditional heteroscedasticity (ARCH) model provides an alternative approach for the simulation of stock heteroscedasticity. In this paper, the application of ARCH and its modified models is presented for the risk analysis...
The performance of optical power transmission through a side polished fiber manufactured by wheel polishing method were investigated, in which materials of different refractive indices were overlaid on the polished surface. The experiments showed that the transmitted optical power through the side-polished fiber varied with the refractive index of the overlaid material. The result of our experiments...
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