Unlike the traditional traction power supply system which enables the electrified railway traction sub- station to be connected to power grid in a way of phase rotation, a new generation traction power supply system w...Unlike the traditional traction power supply system which enables the electrified railway traction sub- station to be connected to power grid in a way of phase rotation, a new generation traction power supply system without phase splits is proposed in this paper. Three key techniques used in this system have been discussed. First, a combined co-phase traction power supply system is applied at traction substations for compensating negative sequence current and eliminating phase splits at exits of substations; design method and procedure for this system are presented. Second, a new bilateral traction power supply technology is proposed to eliminate the phase split at section post and reduce the influence of equalizing current on the power grid. Meanwhile, power factor should be adjusted to ensure a proper voltage level of the traction network. Third, a seg- mental power supply technology of traction network is used to divide the power supply arms into several segments, and the synchronous measurement and control technology is applied to diagnose faults and their locations quickly and accurately. Thus, the fault impact can be limited to a min- imum degree. In addition, the economy and reliability of the new generation traction power supply system are analyzed.展开更多
Multiple sclerosis (MS) is an unpredictable disease of the central nervous system that can range from relatively benign to somewhat disabling to devastating, as communication between the brain and other parts of the b...Multiple sclerosis (MS) is an unpredictable disease of the central nervous system that can range from relatively benign to somewhat disabling to devastating, as communication between the brain and other parts of the body is disrupted. Scientists have learned a great deal about MS in recent years;yet still, its cause remains elusive. This paper intends to investigate the hypothesis that gait dynamics have meaning and may be useful in providing insight into the neural control of locomotion. It further seeks to explore the mutual interactions and influences of MS functions on gait, and vice versa, in a quantitative and robust fashion. Ground reaction forces (GRFs), muscle activities, and segmental accelerations within a gait cycle were analyzed in this study. Patterns of the signals from six relapsing-remitting multiple sclerosis (RRMS) patients were compared with the healthy subjects. This quantitative gait analysis aids to illuminate a better understanding of the mobility-related disease such as RRMS characteristics. An outcome of this study is a reproducible methodology for helping therapists make reliable and differentiable diagnosis, design a tailored therapeutic strategy, and comfortably evaluate the follow-ups on patient’s functional recovery.展开更多
基金supported by the National Natural Science Funds of China (Nos. 51307143 and 51307142)Technology Research and Development Program of China Railway Corporation (No. 2014J009-B)
文摘Unlike the traditional traction power supply system which enables the electrified railway traction sub- station to be connected to power grid in a way of phase rotation, a new generation traction power supply system without phase splits is proposed in this paper. Three key techniques used in this system have been discussed. First, a combined co-phase traction power supply system is applied at traction substations for compensating negative sequence current and eliminating phase splits at exits of substations; design method and procedure for this system are presented. Second, a new bilateral traction power supply technology is proposed to eliminate the phase split at section post and reduce the influence of equalizing current on the power grid. Meanwhile, power factor should be adjusted to ensure a proper voltage level of the traction network. Third, a seg- mental power supply technology of traction network is used to divide the power supply arms into several segments, and the synchronous measurement and control technology is applied to diagnose faults and their locations quickly and accurately. Thus, the fault impact can be limited to a min- imum degree. In addition, the economy and reliability of the new generation traction power supply system are analyzed.
文摘Multiple sclerosis (MS) is an unpredictable disease of the central nervous system that can range from relatively benign to somewhat disabling to devastating, as communication between the brain and other parts of the body is disrupted. Scientists have learned a great deal about MS in recent years;yet still, its cause remains elusive. This paper intends to investigate the hypothesis that gait dynamics have meaning and may be useful in providing insight into the neural control of locomotion. It further seeks to explore the mutual interactions and influences of MS functions on gait, and vice versa, in a quantitative and robust fashion. Ground reaction forces (GRFs), muscle activities, and segmental accelerations within a gait cycle were analyzed in this study. Patterns of the signals from six relapsing-remitting multiple sclerosis (RRMS) patients were compared with the healthy subjects. This quantitative gait analysis aids to illuminate a better understanding of the mobility-related disease such as RRMS characteristics. An outcome of this study is a reproducible methodology for helping therapists make reliable and differentiable diagnosis, design a tailored therapeutic strategy, and comfortably evaluate the follow-ups on patient’s functional recovery.
