A Robot wrist made of a planar step motor with two-degree-of-freedom has been developed recently for a general robot manipulator used in assembly operation.Mechanism design and the magnetic theory of the motor and the...A Robot wrist made of a planar step motor with two-degree-of-freedom has been developed recently for a general robot manipulator used in assembly operation.Mechanism design and the magnetic theory of the motor and the driving system are discussed. The paper also presents several stecial characteritics in designing general step motor (SM) driver This robot end-effector successfully improves the PUMA562 robot's response and locating accuracy.展开更多
With the widespread application of electrification and intelligence of automobiles,the number of electric devices with small DC motors in automobiles has gradually increased,and the in-terior of electric vehicles is q...With the widespread application of electrification and intelligence of automobiles,the number of electric devices with small DC motors in automobiles has gradually increased,and the in-terior of electric vehicles is quieter.The sound quality(SQ)of small motor directly affects the pas-senger experience.Therefore,the research on the SQ of small motor is of great significance.In this paper,the objective quantification of small motor sound quality was investigated based on tradi-tional psychoacoustic metrics.The time-frequency characteristics of sound signal was analyzed to quantify the subjective perception caused by the sound of small motor.And a new psychoacoustic metrics of objective evaluation which were suitable for small motor SQ evaluation were proposed,namely specific loudness energy(SLE),specific prominence ratio index(SPRI),relative pitch exceedance(RPE)and tremolo index(TI).Then,two objective evaluation models of small motor SQ were established to characterize the multi-dimensional subjective perception attributes by using multiple linear regression(MLR)and support vector regression(SVR)respectively,which can be used for the prediction and evaluation of the small motor SQ.The results show that the prediction accuracy of the model established by SVR method was higher than that of MLR,and SVR has stronger robustness.The objective evaluation model of small motors SQ established in this study is of great importance for improving the sound quality of small motors.展开更多
The use of herbal products is increasing in trend globally, with over 75% of the world population using them. In Nigeria, these drinks are popular in many neighbourhoods and sold by vendors in motor parks where commer...The use of herbal products is increasing in trend globally, with over 75% of the world population using them. In Nigeria, these drinks are popular in many neighbourhoods and sold by vendors in motor parks where commercial drivers have access to them. Though they may have some beneficial effects, they are not completely harmless. This study was carried out to assess the association of Paraga (herbal mixture) consumption and dietary lifestyle on the nutritional status of commercial motor drivers in Ibadan municipality. This descriptive cross-sectional study was carried out among four hundred and twenty-two (422) commercial drivers randomly selected from the five local government areas that make up Ibadan municipality. A structured questionnaire was used to collect data from the respondents. Descriptive statistics and Chi square test were carried out on the data obtained at 5% level of significance. There was a high prevalence of Paraga consumption among the respondents. There was inadequate nutrient intake among the respondents for most nutrients considered. The nutritional status measurement of the respondents revealed that 4.5% were underweight, 59.6% had normal weight, 26.8% were overweight, while 9.1% were obese. There was no significant association between Paraga consumption and nutritional status of respondents (p > 0.05). However, a significant association was observed between dietary lifestyle pattern and nutritional status of respondents (p < 0.05). It is therefore important that commercial drivers be given regular and constant nutrition education during their meetings to help improve their dietary lifestyle. Also, the concerned government agencies/officials should assist in reducing Paraga consumption by helping to reduce alcohol availability at motor parks, and by educational measures to reduce its demand and consumption.展开更多
本文提出一种跨被试的深度神经网络识别方法,应对运动想象脑电信号的非线性、非平稳特性.该方法首先计算协方差矩阵均值,将不同被试者样本集的协方差对齐至单位矩阵,提升样本的被试间泛化性.然后,将对齐后的样本输入至卷积神经网络中,...本文提出一种跨被试的深度神经网络识别方法,应对运动想象脑电信号的非线性、非平稳特性.该方法首先计算协方差矩阵均值,将不同被试者样本集的协方差对齐至单位矩阵,提升样本的被试间泛化性.然后,将对齐后的样本输入至卷积神经网络中,通过留一被试交叉验证法,构建跨被试的运动想象脑电信号识别方法.在BCI Competition IV dataset 2b公开数据集上进行实验,结果表明,新的方法在该数据集上取得了高的识别性能,且测试场景中的时间复杂度与现有方法相同.展开更多
文摘A Robot wrist made of a planar step motor with two-degree-of-freedom has been developed recently for a general robot manipulator used in assembly operation.Mechanism design and the magnetic theory of the motor and the driving system are discussed. The paper also presents several stecial characteritics in designing general step motor (SM) driver This robot end-effector successfully improves the PUMA562 robot's response and locating accuracy.
基金supported by the National Natural Science Found-ation of China(No.5217051173)。
文摘With the widespread application of electrification and intelligence of automobiles,the number of electric devices with small DC motors in automobiles has gradually increased,and the in-terior of electric vehicles is quieter.The sound quality(SQ)of small motor directly affects the pas-senger experience.Therefore,the research on the SQ of small motor is of great significance.In this paper,the objective quantification of small motor sound quality was investigated based on tradi-tional psychoacoustic metrics.The time-frequency characteristics of sound signal was analyzed to quantify the subjective perception caused by the sound of small motor.And a new psychoacoustic metrics of objective evaluation which were suitable for small motor SQ evaluation were proposed,namely specific loudness energy(SLE),specific prominence ratio index(SPRI),relative pitch exceedance(RPE)and tremolo index(TI).Then,two objective evaluation models of small motor SQ were established to characterize the multi-dimensional subjective perception attributes by using multiple linear regression(MLR)and support vector regression(SVR)respectively,which can be used for the prediction and evaluation of the small motor SQ.The results show that the prediction accuracy of the model established by SVR method was higher than that of MLR,and SVR has stronger robustness.The objective evaluation model of small motors SQ established in this study is of great importance for improving the sound quality of small motors.
文摘The use of herbal products is increasing in trend globally, with over 75% of the world population using them. In Nigeria, these drinks are popular in many neighbourhoods and sold by vendors in motor parks where commercial drivers have access to them. Though they may have some beneficial effects, they are not completely harmless. This study was carried out to assess the association of Paraga (herbal mixture) consumption and dietary lifestyle on the nutritional status of commercial motor drivers in Ibadan municipality. This descriptive cross-sectional study was carried out among four hundred and twenty-two (422) commercial drivers randomly selected from the five local government areas that make up Ibadan municipality. A structured questionnaire was used to collect data from the respondents. Descriptive statistics and Chi square test were carried out on the data obtained at 5% level of significance. There was a high prevalence of Paraga consumption among the respondents. There was inadequate nutrient intake among the respondents for most nutrients considered. The nutritional status measurement of the respondents revealed that 4.5% were underweight, 59.6% had normal weight, 26.8% were overweight, while 9.1% were obese. There was no significant association between Paraga consumption and nutritional status of respondents (p > 0.05). However, a significant association was observed between dietary lifestyle pattern and nutritional status of respondents (p < 0.05). It is therefore important that commercial drivers be given regular and constant nutrition education during their meetings to help improve their dietary lifestyle. Also, the concerned government agencies/officials should assist in reducing Paraga consumption by helping to reduce alcohol availability at motor parks, and by educational measures to reduce its demand and consumption.
文摘本文提出一种跨被试的深度神经网络识别方法,应对运动想象脑电信号的非线性、非平稳特性.该方法首先计算协方差矩阵均值,将不同被试者样本集的协方差对齐至单位矩阵,提升样本的被试间泛化性.然后,将对齐后的样本输入至卷积神经网络中,通过留一被试交叉验证法,构建跨被试的运动想象脑电信号识别方法.在BCI Competition IV dataset 2b公开数据集上进行实验,结果表明,新的方法在该数据集上取得了高的识别性能,且测试场景中的时间复杂度与现有方法相同.
