城市道路拥堵状态下驾驶人心率特性研究

为了量化交通拥堵对驾驶人生理和心理特性的影响,选取驾驶人的心率均值为指标,在大量实测数据基础上研究交通拥堵程度对驾驶人心率特性的影响,并构建心率均值和压力系数间的关系模型。研究表明,交通拥堵对驾驶人的心率特性影响显著,3种回归模型拟合优度的确定系数都达到了0.6以上,且二次多项式的回归效果最好。

Phylogeography and Characteristics of Phosphorus Efficiency of Secondary Core Collection for Rice Landraces in Yunnan Province

[Objective] The paper was to explore the causes of phosphorus(P)efficiency of rice in Yunnan Province,and to provide strategy for ecological and environmental protection.[Method]Using 703 accessions of secondary core collections from 16 prefectures of five regions in Yunnan Province,two treatments of low available P(6.26mg/kg)versus normal P(available P 40mg/kg),and invalid P(available P 0.02 mg/kg)versus normal P(available P 70 mg/kg)were set,and zonal characteristics of phosphorus efficiency and the activation characteristics of invalid P of rice landraces were investigated.[Result] Phosphorus efficiency and the activation characteristics of invalid P in soils from rice landraces of Yunnan Province had the similar identification indexes,viz.the relative indexes of four traits(tillering ability or effective panicle,root weight,biomass,and straw weight)could be the screening indexes of gene type of secondary core collection with phosphorus efficiency,which also reflected the zonal characteristics of phosphorus efficiency and the activation characteristics of invalid P in soils of 16 prefectures among five regions.On the contrary,the relative panicle length,node length under panicle,leaf length,leaf width and plant height could only be the assistant indexes of identification for phosphorus efficiency.There were similar zonal characteristics between phosphorus efficiency and the activation characteristics of invalid P in soils of rice landraces in Yunnan Province.[Conclusion] The study had great importance to the conservation and utilization of biological diversity,which would make contribution to second green revolution of "less input,multiple output,promote health,and protect the environment".

Simplified Method of Designing FIR Filter with Controllable Center Frequency

A novel simplified method is presented to design FIR filter with controllable center frequency. The properties of transfer curves for all-phase filters are illustrated under 3 windowing conditions. By combining single-window all-phase filter design steps and double phase-shift combination, a series of design formulas for point-pass filter, notch filter, band-pass filter and band-stop filter are derived, thus the design computation complexity is greatly reduced. Experiments prove that the center frequency of all the filters can be accurately specified at arbitrary position by adjusting frequency parameters m and λ.

Characteristic Functions over C*-Probability Spaces

Various properties of the characteristic functions of random variables in a non-commutative C*-probability space are studied in this paper. It turns out that the distributions of random variables are uniquely determined by their characteristic functions. By using the properties of characteristic functions, a central limit theorem for a sequence of independent identically distributed random variables in a C*-probability space is established as well.

Complexity and characteristic frequency studies in ECG signals of mice based on multiple scale factors

Existing methods of physiological signal analysis based on nonlinear dynamic theories only examine the complexity difference of the signals under a single sampling frequency.We developed a technique to measure the multifractal characteristic parameter intimately associated with physiological activities through a frequency scale factor.This parameter is highly sensitive to physiological and pathological status.Mice received various drugs to imitate different physiological and pathological conditions,and the distributions of mass exponent spectrum curvature with scale factors from the electrocardiogram (ECG) signals of healthy and drug injected mice were determined.Next,we determined the characteristic frequency scope in which the signal was of the highest complexity and most sensitive to impaired cardiac function,and examined the relationships between heart rate,heartbeat dynamic complexity,and sensitive frequency scope of the ECG signal.We found that all animals exhibited a scale factor range in which the absolute magnitudes of ECG mass exponent spectrum curvature achieve the maximum,and this range (or frequency scope) is not changed with calculated data points or maximal coarse-grained scale factor.Further,the heart rate of mice was not necessarily associated with the nonlinear complexity of cardiac dynamics,but closely related to the most sensitive ECG frequency scope determined by characterization of this complex dynamic features for certain heartbeat conditions.Finally,we found that the health status of the hearts of mice was directly related to the heartbeat dynamic complexity,both of which were positively correlated within the scale factor around the extremum region of the multifractal parameter.With increasing heart rate,the sensitive frequency scope increased to a relatively high location.In conclusion,these data provide important theoretical and practical data for the early diagnosis of cardiac disorders.