The reconstruction of background noise from an error signal of an adaptive filter is a key issue for developing Variable Step-Size Normalized Least Mean Square (VSS-NLMS) algorithm in the context of Echo Cancellation ...The reconstruction of background noise from an error signal of an adaptive filter is a key issue for developing Variable Step-Size Normalized Least Mean Square (VSS-NLMS) algorithm in the context of Echo Cancellation (EC). The core parameter in this algorithm is the Background Noise Power (BNP); in the estimation of BNP, the power difference between the desired signal and the filter output, statistically equaling to the error signal power, has been widely used in a rough manner. In this study, a precise BNP estimate is implemented by multiplying the rough estimate with a corrective factor, taking into consideration the fact that the error signal consists of background noise and misalignment noise. This corrective factor is obtained by subtracting half of the latest VSS value from 1 after analyzing the ratio of BNP to the misalignment noise. Based on the precise BNP estimate, the PVSS-NLMS algorithm suitable for the EC system is eventually proposed. In practice, the proposed algorithm exhibits a significant advantage of easier controllability application, as prior knowledge of the EC environment can be neglected. The simulation results support the preciseness of the BNP estimation and the effectiveness of the proposed algorithm.展开更多
The adaptive algorithm used for echo cancellation(EC) system needs to provide 1) low misadjustment and 2) high convergence rate. The affine projection algorithm(APA) is a better alternative than normalized least mean ...The adaptive algorithm used for echo cancellation(EC) system needs to provide 1) low misadjustment and 2) high convergence rate. The affine projection algorithm(APA) is a better alternative than normalized least mean square(NLMS) algorithm in EC applications where the input signal is highly correlated. Since the APA with a constant step-size has to make compromise between the performance criteria 1) and 2), a variable step-size APA(VSS-APA) provides a more reliable solution. A nonparametric VSS-APA(NPVSS-APA) is proposed by recovering the background noise within the error signal instead of cancelling the a posteriori errors. The most problematic term of its variable step-size formula is the value of background noise power(BNP). The power difference between the desired signal and output signal, which equals the power of error signal statistically, has been considered the BNP estimate in a rough manner. Considering that the error signal consists of background noise and misalignment noise, a precise BNP estimate is achieved by multiplying the rough estimate with a corrective factor. After the analysis on the power ratio of misalignment noise to background noise of APA, the corrective factor is formulated depending on the projection order and the latest value of variable step-size. The new algorithm which does not require any a priori knowledge of EC environment has the advantage of easier controllability in practical application. The simulation results in the EC context indicate the accuracy of the proposed BNP estimate and the more effective behavior of the proposed algorithm compared with other versions of APA class.展开更多
This paper seeks to exemplify some of the intentional and unintentional nonverbal communication attempts expressea Dy children with Autism Spectrum Disorder （ASD） syndrome. It demonstrates that such interactions wit...This paper seeks to exemplify some of the intentional and unintentional nonverbal communication attempts expressea Dy children with Autism Spectrum Disorder （ASD） syndrome. It demonstrates that such interactions with the rest of the world are trying to establish some semiotic functions, in an effort behaviorally to overcome the children＇s disability. The author＇s aim is to analyze such a paradoxical way of communicational interaction of such a subject vs. a given objectively perceivable reality, thus attempting to reveal paradoxical social contexts. The focus is on interpersonal communication abilities and/or disabilities, thus allowing semiotically distinguishable units as an object of analysis. The problem of mental disorders, such as ASD, requires a multi-dimensional approach--e.g., biological, medical, and other related fields. In conclusion, by applying a semiotic analysis, it becomes necessary to communicate with such children in a whole new way which, by processes of transformation, can bring about a state of awareness of a paradoxical and/or abnormal phenomenon.展开更多
An adaptive morphological impulses extraction method （AMIE） for bearing fault diagnosis is pro- posed. This method uses the morphological closing operation with a flat structuring element （SE） to extract impulsive...An adaptive morphological impulses extraction method （AMIE） for bearing fault diagnosis is pro- posed. This method uses the morphological closing operation with a flat structuring element （SE） to extract impulsive features from vibration signals with strong background noise. To optimize the flat SE, firstly, a theoretical study is carried out to investigate the effects of the length of the flat SE. Then, based on the theoretical findings, an adaptive algorithm for the flat SE optimization is proposed. The AMIE method is tested by the simulated signal and bearing vibration signals. The test results show that this method is effective and robust in extracting impulsive features.展开更多
0.5μm-gate-length lateral double-diffused metal-oxide-semiconductor field-effect transistors （LDMOSFETs） with low barrier body contact （LBBC） and body tied to the source （BTS） were fabricated on silicon-on-insu...0.5μm-gate-length lateral double-diffused metal-oxide-semiconductor field-effect transistors （LDMOSFETs） with low barrier body contact （LBBC） and body tied to the source （BTS） were fabricated on silicon-on-insulator （SOI） substrates. The back-gate effects on front-channel subthreshold characteristics, on-resistance, and off-state breakdown characteristics of these devices are studied in detail. The LDMOSFETs with the LBBC structure show less back-gate effect than those with the BTS structure due to better control of the floating body effect and suppression of the parasitic backchannel leakage current. A model for the SOl LDMOSFETs has been given,including the front- and back-channel conductions as well as the bias-dependent series resistance.展开更多
This paper reports the attempt to apply the functional approach to the translation teaching practice that guides students in their study of Chinese essays and their English translations. The famed modern Chinese essay...This paper reports the attempt to apply the functional approach to the translation teaching practice that guides students in their study of Chinese essays and their English translations. The famed modern Chinese essay Belying and its three English translations were taken for case study from the perspective of Experiential Function in Systemic Functional Linguistics. A process type analysis of Beiying and its English translations was conducted, including analysis of texts, sample processes, distributions of process types in Beiying and analyses of similarities and differences in the distributions. Results are as follows： 1） The similarities between English and Chinese texts lie in the experiential world, which makes translation possible. The process types in the essay text are directly related to genre, and the material process predominates among the process types in essay texts. 2） The differences are that the percentage of the material process in the ST is higher than that in the three English translations, and this shows the characteristics of verb-prominence in Chinese and nominalization in English. 3） Cultural differences in translation are the root-cause of linguistic differences. These results from the case of practicing the functional approach to the teaching of translation can help students gain understanding of English translations of Beiying and can provide some inspiration for the teaching of Chinese-English essay translation and the related studies.展开更多
文摘The reconstruction of background noise from an error signal of an adaptive filter is a key issue for developing Variable Step-Size Normalized Least Mean Square (VSS-NLMS) algorithm in the context of Echo Cancellation (EC). The core parameter in this algorithm is the Background Noise Power (BNP); in the estimation of BNP, the power difference between the desired signal and the filter output, statistically equaling to the error signal power, has been widely used in a rough manner. In this study, a precise BNP estimate is implemented by multiplying the rough estimate with a corrective factor, taking into consideration the fact that the error signal consists of background noise and misalignment noise. This corrective factor is obtained by subtracting half of the latest VSS value from 1 after analyzing the ratio of BNP to the misalignment noise. Based on the precise BNP estimate, the PVSS-NLMS algorithm suitable for the EC system is eventually proposed. In practice, the proposed algorithm exhibits a significant advantage of easier controllability application, as prior knowledge of the EC environment can be neglected. The simulation results support the preciseness of the BNP estimation and the effectiveness of the proposed algorithm.
文摘The adaptive algorithm used for echo cancellation(EC) system needs to provide 1) low misadjustment and 2) high convergence rate. The affine projection algorithm(APA) is a better alternative than normalized least mean square(NLMS) algorithm in EC applications where the input signal is highly correlated. Since the APA with a constant step-size has to make compromise between the performance criteria 1) and 2), a variable step-size APA(VSS-APA) provides a more reliable solution. A nonparametric VSS-APA(NPVSS-APA) is proposed by recovering the background noise within the error signal instead of cancelling the a posteriori errors. The most problematic term of its variable step-size formula is the value of background noise power(BNP). The power difference between the desired signal and output signal, which equals the power of error signal statistically, has been considered the BNP estimate in a rough manner. Considering that the error signal consists of background noise and misalignment noise, a precise BNP estimate is achieved by multiplying the rough estimate with a corrective factor. After the analysis on the power ratio of misalignment noise to background noise of APA, the corrective factor is formulated depending on the projection order and the latest value of variable step-size. The new algorithm which does not require any a priori knowledge of EC environment has the advantage of easier controllability in practical application. The simulation results in the EC context indicate the accuracy of the proposed BNP estimate and the more effective behavior of the proposed algorithm compared with other versions of APA class.
文摘This paper seeks to exemplify some of the intentional and unintentional nonverbal communication attempts expressea Dy children with Autism Spectrum Disorder （ASD） syndrome. It demonstrates that such interactions with the rest of the world are trying to establish some semiotic functions, in an effort behaviorally to overcome the children＇s disability. The author＇s aim is to analyze such a paradoxical way of communicational interaction of such a subject vs. a given objectively perceivable reality, thus attempting to reveal paradoxical social contexts. The focus is on interpersonal communication abilities and/or disabilities, thus allowing semiotically distinguishable units as an object of analysis. The problem of mental disorders, such as ASD, requires a multi-dimensional approach--e.g., biological, medical, and other related fields. In conclusion, by applying a semiotic analysis, it becomes necessary to communicate with such children in a whole new way which, by processes of transformation, can bring about a state of awareness of a paradoxical and/or abnormal phenomenon.
基金Supported by the High Technology Research and Development Programme of China （No. 2007AA04Z433） and the National Natural Science Foundation of China （No. 50635010）.
文摘An adaptive morphological impulses extraction method （AMIE） for bearing fault diagnosis is pro- posed. This method uses the morphological closing operation with a flat structuring element （SE） to extract impulsive features from vibration signals with strong background noise. To optimize the flat SE, firstly, a theoretical study is carried out to investigate the effects of the length of the flat SE. Then, based on the theoretical findings, an adaptive algorithm for the flat SE optimization is proposed. The AMIE method is tested by the simulated signal and bearing vibration signals. The test results show that this method is effective and robust in extracting impulsive features.
基金the National Natural Science Foundation of China(No.60576051)the State Key Development Program for Basic Research of China(No.2006CB3027-01)~~
文摘0.5μm-gate-length lateral double-diffused metal-oxide-semiconductor field-effect transistors （LDMOSFETs） with low barrier body contact （LBBC） and body tied to the source （BTS） were fabricated on silicon-on-insulator （SOI） substrates. The back-gate effects on front-channel subthreshold characteristics, on-resistance, and off-state breakdown characteristics of these devices are studied in detail. The LDMOSFETs with the LBBC structure show less back-gate effect than those with the BTS structure due to better control of the floating body effect and suppression of the parasitic backchannel leakage current. A model for the SOl LDMOSFETs has been given,including the front- and back-channel conductions as well as the bias-dependent series resistance.
文摘This paper reports the attempt to apply the functional approach to the translation teaching practice that guides students in their study of Chinese essays and their English translations. The famed modern Chinese essay Belying and its three English translations were taken for case study from the perspective of Experiential Function in Systemic Functional Linguistics. A process type analysis of Beiying and its English translations was conducted, including analysis of texts, sample processes, distributions of process types in Beiying and analyses of similarities and differences in the distributions. Results are as follows： 1） The similarities between English and Chinese texts lie in the experiential world, which makes translation possible. The process types in the essay text are directly related to genre, and the material process predominates among the process types in essay texts. 2） The differences are that the percentage of the material process in the ST is higher than that in the three English translations, and this shows the characteristics of verb-prominence in Chinese and nominalization in English. 3） Cultural differences in translation are the root-cause of linguistic differences. These results from the case of practicing the functional approach to the teaching of translation can help students gain understanding of English translations of Beiying and can provide some inspiration for the teaching of Chinese-English essay translation and the related studies.
