Both the seat and cab system of truck play a vital role in ride comfort.The damping matching methods of the two systems are studied separately at present.However,the driver,seat,and cab system are one inseparable whol...Both the seat and cab system of truck play a vital role in ride comfort.The damping matching methods of the two systems are studied separately at present.However,the driver,seat,and cab system are one inseparable whole.In order to further improve ride comfort,the seat suspension is regarded as the fifth suspension of the cab,a new idea of ＂Five-suspensions＂ is proposed.Based on this idea,a 4 degree-of-freedom driver-seat-cab coupled system model is presented.Using the tested cab suspensions excitations as inputs and seat acceleration response as compared output,the simulation model is built.Taking optimal ride comfort as target,a new method of damping collaborative optimization for Five-suspensions is proposed.With a practical example of seat and cab system,the damping parameters are optimized and validated by simulation and bench test.The results show the seat vertical frequency-weighted RMS acceleration values tested for the un-optimized and optimized Five-suspensions are 0.50 m/s～2 and 0.39 m/s～2,respectively,with a decrease by 22.0%,which proves the model and method proposed are correct and reliable.The idea of ＂Five-suspensions＂ and the method proposed provide a reference for achieving global optimal damping matching of seat suspension and cab suspensions.展开更多
Water is the key medium to transport numerous constituents and to provide a platform for physiological processes to take place in the living organisms in general;it also participates actively in many of these processe...Water is the key medium to transport numerous constituents and to provide a platform for physiological processes to take place in the living organisms in general;it also participates actively in many of these processes. In humans, there are different vehicles to contain water and its constituents. Our objective is to find out whether there is an overall water-base circulation system in the human body by analyzing the updated findings of different research groups on the physiological functions of various seemingly isolated fluid systems. By 1963, there were five separate fluid systems discovered in mammalians: (i) The Primo Vasculature Fluid (PVF) with protein precursors and micro cells held in the Primo Vasculature System (PVS). (ii) Blood with its constituents held in the cardio vasculature. (iii) Extracranial interstitial fluid (ISF) whose vehicle had a very irregular structure—the interstitium all over the body. (iv) The cerebrospinal fluid had been considered to be within the brain ventricles and spinal canal. (v) The extra-cranial lymphatic system which drained ISF, and had been known to join the subclavian vein. Fluid (i) was first reported in 1963 and fluids (ii) to (v) have been known for many decades, but the failure to detect a lymphatic system inside the skull has also been a mystery for many decades. The intra-cranial ISF (which we name as BISF) has drawn little attention, apart from discussing the mechanism of the blood-brain-barrier. During the past decade, there has been direct evidence indicating that CSF and BISF are actually mixed. After that, the intracranial lymphatic system was discovered and confirmed in animal models only slightly over one year back, and we called such fluid as glymphatic-fluid. After reviewing the stated “classical” five fluid systems together with the new findings in Sections 2 - 7, we propose, for the first time, that the PVF, the blood, ISF, a mixture of CSF-BISF, and a mixture of glymphatic-fluid and lymph form an integrative circulation system in water base in the human and other mammalian bodies, as schematically represented in the last section. In this paper, we point out the positive correlation of chronic neuro degenerative diseases such as Alzheimer’s disease, Parkinson’s diseases and the insufficient brain wastes clearance by the glymphatic system. We also discuss the role played by the venous vessels as part of such clearance in upright posture. Moreover, simple non-invasive maneuver techniques are introduced here, as one example of enhancement of glymphatic fluid flow out of the skull to join the lymphatic system. A series of questions are raised in Section 8, the answers to which would help us to understand the transition from physio- to pathological states in the development of many diseases. Detailed analysis of this paper leads us to consider that research in understanding this integrative circulation system is only at the infancy stage, and fluid dynamics investigation seems to be the plausible modality of approach in the near future.展开更多
We consider a five-electron system in the Hubbard model with a coupling between nearest-neighbors. The structure of essential spectrum and discrete spectrum of the systems in the third and fourth doublet states in a &...We consider a five-electron system in the Hubbard model with a coupling between nearest-neighbors. The structure of essential spectrum and discrete spectrum of the systems in the third and fourth doublet states in a <em>v</em>-dimensional lattice is investigated. We prove that the essential spectrum of the system in a third doublet state consists is the union of at most four segments, and discrete spectrum of the system is empty. We show that the essential spectrum of the system in a fourth doublet state consists of the union of at most seven segments, and discrete spectrum of the system consists of no more than one point.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51575325)Shandong Provincial Natural Science Foundation of China(Grant No.ZR2013EEM007)
文摘Both the seat and cab system of truck play a vital role in ride comfort.The damping matching methods of the two systems are studied separately at present.However,the driver,seat,and cab system are one inseparable whole.In order to further improve ride comfort,the seat suspension is regarded as the fifth suspension of the cab,a new idea of ＂Five-suspensions＂ is proposed.Based on this idea,a 4 degree-of-freedom driver-seat-cab coupled system model is presented.Using the tested cab suspensions excitations as inputs and seat acceleration response as compared output,the simulation model is built.Taking optimal ride comfort as target,a new method of damping collaborative optimization for Five-suspensions is proposed.With a practical example of seat and cab system,the damping parameters are optimized and validated by simulation and bench test.The results show the seat vertical frequency-weighted RMS acceleration values tested for the un-optimized and optimized Five-suspensions are 0.50 m/s～2 and 0.39 m/s～2,respectively,with a decrease by 22.0%,which proves the model and method proposed are correct and reliable.The idea of ＂Five-suspensions＂ and the method proposed provide a reference for achieving global optimal damping matching of seat suspension and cab suspensions.
文摘Water is the key medium to transport numerous constituents and to provide a platform for physiological processes to take place in the living organisms in general;it also participates actively in many of these processes. In humans, there are different vehicles to contain water and its constituents. Our objective is to find out whether there is an overall water-base circulation system in the human body by analyzing the updated findings of different research groups on the physiological functions of various seemingly isolated fluid systems. By 1963, there were five separate fluid systems discovered in mammalians: (i) The Primo Vasculature Fluid (PVF) with protein precursors and micro cells held in the Primo Vasculature System (PVS). (ii) Blood with its constituents held in the cardio vasculature. (iii) Extracranial interstitial fluid (ISF) whose vehicle had a very irregular structure—the interstitium all over the body. (iv) The cerebrospinal fluid had been considered to be within the brain ventricles and spinal canal. (v) The extra-cranial lymphatic system which drained ISF, and had been known to join the subclavian vein. Fluid (i) was first reported in 1963 and fluids (ii) to (v) have been known for many decades, but the failure to detect a lymphatic system inside the skull has also been a mystery for many decades. The intra-cranial ISF (which we name as BISF) has drawn little attention, apart from discussing the mechanism of the blood-brain-barrier. During the past decade, there has been direct evidence indicating that CSF and BISF are actually mixed. After that, the intracranial lymphatic system was discovered and confirmed in animal models only slightly over one year back, and we called such fluid as glymphatic-fluid. After reviewing the stated “classical” five fluid systems together with the new findings in Sections 2 - 7, we propose, for the first time, that the PVF, the blood, ISF, a mixture of CSF-BISF, and a mixture of glymphatic-fluid and lymph form an integrative circulation system in water base in the human and other mammalian bodies, as schematically represented in the last section. In this paper, we point out the positive correlation of chronic neuro degenerative diseases such as Alzheimer’s disease, Parkinson’s diseases and the insufficient brain wastes clearance by the glymphatic system. We also discuss the role played by the venous vessels as part of such clearance in upright posture. Moreover, simple non-invasive maneuver techniques are introduced here, as one example of enhancement of glymphatic fluid flow out of the skull to join the lymphatic system. A series of questions are raised in Section 8, the answers to which would help us to understand the transition from physio- to pathological states in the development of many diseases. Detailed analysis of this paper leads us to consider that research in understanding this integrative circulation system is only at the infancy stage, and fluid dynamics investigation seems to be the plausible modality of approach in the near future.
文摘We consider a five-electron system in the Hubbard model with a coupling between nearest-neighbors. The structure of essential spectrum and discrete spectrum of the systems in the third and fourth doublet states in a <em>v</em>-dimensional lattice is investigated. We prove that the essential spectrum of the system in a third doublet state consists is the union of at most four segments, and discrete spectrum of the system is empty. We show that the essential spectrum of the system in a fourth doublet state consists of the union of at most seven segments, and discrete spectrum of the system consists of no more than one point.
