To realize multi-signal joint diagnosis in circuit breaker's state evaluation methods,and to improve their evaluation accuracy,we proposed an intelligent evaluation model of circuit breaker mechanical properties b...To realize multi-signal joint diagnosis in circuit breaker's state evaluation methods,and to improve their evaluation accuracy,we proposed an intelligent evaluation model of circuit breaker mechanical properties based on multiagent system.Taking a circuit breaker which has mono-stable permanent magnetic operating mechanism as the example,its model involves four kinds of signals: auxiliary contact,operating mechanism current,travel of the contact,and mechanical vibration.Detailed analyses on the evaluation agent's architecture and the process of the system's multiagent evaluation and ratiocination were also proposed.Moreover,it is proved by three application cases that the proposed method could accurately evaluate circuit breaker status not only with normal signals,but also in certain signal failure situations;meanwhile the model has a strong self-learning ability.展开更多
An improved speech absence probability estimation was proposed using environmental noise classification for speech enhancement.A relevant noise estimation approach,known as the speech presence uncertainty tracking met...An improved speech absence probability estimation was proposed using environmental noise classification for speech enhancement.A relevant noise estimation approach,known as the speech presence uncertainty tracking method,requires seeking the "a priori" probability of speech absence that is derived by applying microphone input signal and the noise signal based on the estimated value of the "a posteriori" signal-to-noise ratio(SNR).To overcome this problem,first,the optimal values in terms of the perceived speech quality of a variety of noise types are derived.Second,the estimated optimal values are assigned according to the determined noise type which is classified by a real-time noise classification algorithm based on the Gaussian mixture model(GMM).The proposed algorithm estimates the speech absence probability using a noise classification algorithm which is based on GMM to apply the optimal parameter of each noise type,unlike the conventional approach which uses a fixed threshold and smoothing parameter.The performance of the proposed method was evaluated by objective tests,such as the perceptual evaluation of speech quality(PESQ) and composite measure.Performance was then evaluated by a subjective test,namely,mean opinion scores(MOS) under various noise environments.The proposed method show better results than existing methods.展开更多
Straightening machine is widely used for improving the quality of the defective mild steel plates.In general,the capacity of straightening machine is affected by material properties,the initial shape of the incoming p...Straightening machine is widely used for improving the quality of the defective mild steel plates.In general,the capacity of straightening machine is affected by material properties,the initial shape of the incoming plate and the plastic ratio.The mechanics model describing the capacity of the machine was developed.The deviation of the straightening capacity curves was studied.Then,the presented model was evaluated by comparative study to filed production data.Finally,the influences of overstretch,straightening speed,strengthening coefficient,elastic modulus,width of the plate on the straightening capacity were studied.It is convenient to determine whether the plate can be straightened or not by a series of straightening capacity curves.The straightening speed,width of the plate and elastic modulus of the material are more sensitive to the straightening capacity than the strengthening coefficient.展开更多
基金Project supported by National Natural Science Foundation of China(51177104)
文摘To realize multi-signal joint diagnosis in circuit breaker's state evaluation methods,and to improve their evaluation accuracy,we proposed an intelligent evaluation model of circuit breaker mechanical properties based on multiagent system.Taking a circuit breaker which has mono-stable permanent magnetic operating mechanism as the example,its model involves four kinds of signals: auxiliary contact,operating mechanism current,travel of the contact,and mechanical vibration.Detailed analyses on the evaluation agent's architecture and the process of the system's multiagent evaluation and ratiocination were also proposed.Moreover,it is proved by three application cases that the proposed method could accurately evaluate circuit breaker status not only with normal signals,but also in certain signal failure situations;meanwhile the model has a strong self-learning ability.
基金Project supported by an Inha University Research GrantProject(10031764) supported by the Strategic Technology Development Program of Ministry of Knowledge Economy,Korea
文摘An improved speech absence probability estimation was proposed using environmental noise classification for speech enhancement.A relevant noise estimation approach,known as the speech presence uncertainty tracking method,requires seeking the "a priori" probability of speech absence that is derived by applying microphone input signal and the noise signal based on the estimated value of the "a posteriori" signal-to-noise ratio(SNR).To overcome this problem,first,the optimal values in terms of the perceived speech quality of a variety of noise types are derived.Second,the estimated optimal values are assigned according to the determined noise type which is classified by a real-time noise classification algorithm based on the Gaussian mixture model(GMM).The proposed algorithm estimates the speech absence probability using a noise classification algorithm which is based on GMM to apply the optimal parameter of each noise type,unlike the conventional approach which uses a fixed threshold and smoothing parameter.The performance of the proposed method was evaluated by objective tests,such as the perceptual evaluation of speech quality(PESQ) and composite measure.Performance was then evaluated by a subjective test,namely,mean opinion scores(MOS) under various noise environments.The proposed method show better results than existing methods.
文摘Straightening machine is widely used for improving the quality of the defective mild steel plates.In general,the capacity of straightening machine is affected by material properties,the initial shape of the incoming plate and the plastic ratio.The mechanics model describing the capacity of the machine was developed.The deviation of the straightening capacity curves was studied.Then,the presented model was evaluated by comparative study to filed production data.Finally,the influences of overstretch,straightening speed,strengthening coefficient,elastic modulus,width of the plate on the straightening capacity were studied.It is convenient to determine whether the plate can be straightened or not by a series of straightening capacity curves.The straightening speed,width of the plate and elastic modulus of the material are more sensitive to the straightening capacity than the strengthening coefficient.
