Effect of Common Driving Sources to the Feedback Analysis of Heart Rate Variability

2007 ◽  
Vol 46 (02) ◽  
pp. 202-205 ◽  
Author(s):  
S. Nishiyama ◽  
K. Mitsui ◽  
Y. Yamazaki ◽  
H. Mizuta ◽  
K. Yana

Summary Objectives : This paper examines the operational characteristics of the multivariate autoregressive analysis applied to the simultaneous recordings of the instantaneous heart rate (IHR) and the change in systolic blood pressure (SBP). Methods : The multivariate autoregressive model has been utilized to reveal the feedback characteristics between IHR and SBP. The model assumes the presence of independent set of driving forces to activate the system. However, it is likely that the driving forces may have correlation due to the presence of a common fluctuation source. This paper examines the effect of the presence of correlated components in the driving forces to the estimation accuracy of impulse responses characterizing the feedback properties. The twodimensional autoregressive model driven bytwo correlated 1/f noises was chosen for the analysis of operational characteristics. The driving force was generated by a moving average system which simulates non-integer order integration. Results : Computer simulation revealed that the mean square estimation errors of impulse responses sharply increase as relative power of common driving force exceeds 50%. However, the estimation accuracy and bias are found to be in permissible range in practice. Conclusions : These findings ensure the practical validity of utilizing multivariate autoregressive models for the feedback analysis between IHR and SBP where both signals have the common driving force.

Author(s):  
Bernhard Hommel

AbstractCommonsense and theorizing about action control agree in assuming that human behavior is (mainly) driven by goals, but no mechanistic theory of what goals are, where they come from, and how they impact action selection is available. Here I develop such a theory that is based on the assumption that GOALs guide Intentional Actions THrough criteria (GOALIATH). The theory is intended to be minimalist and parsimonious with respect to its assumptions, as transparent and mechanistic as possible, and it is based on representational assumptions provided by the Theory of Event Coding (TEC). It holds that goal-directed behavior is guided by selection criteria that activate and create competition between event files that contain action-effect codes matching one or more of the criteria—a competition that eventually settles into a solution favoring the best-matching event file. The criteria are associated with various sources, including biological drives, acquired needs (e.g., of achievement, power, or affiliation), and short-term, sometimes arbitrary, instructed aims. Action selection is, thus, a compromise that tries to satisfy various criteria related to different driving forces, which are also likely to vary in strength over time. Hence, what looks like goal-directed action emerges from, and represents an attempt to satisfy multiple constraints with different origins, purposes, operational characteristics, and timescales—which among other things does not guarantee a high degree of coherence or rationality of the eventual outcome. GOALIATH calls for a radical break with conventional theorizing about the control of goal-directed behavior, as it among other things questions existing cognitive-control theories and dual-route models of action control.


Author(s):  
Xiandong Zhou ◽  
Christoph Reimuth ◽  
Peter Stein ◽  
Bai-Xiang Xu

AbstractThis work presents a regularized eigenstrain formulation around the slip plane of dislocations and the resultant non-singular solutions for various dislocation configurations. Moreover, we derive the generalized Eshelby stress tensor of the configurational force theory in the context of the proposed dislocation model. Based on the non-singular finite element solutions and the generalized configurational force formulation, we calculate the driving force on dislocations of various configurations, including single edge/screw dislocation, dislocation loop, interaction between a vacancy dislocation loop and an edge dislocation, as well as a dislocation cluster. The non-singular solutions and the driving force results are well benchmarked for different cases. The proposed formulation and the numerical scheme can be applied to any general dislocation configuration with complex geometry and loading conditions.


2018 ◽  
Vol 22 (3) ◽  
pp. 194-211 ◽  
Author(s):  
Yongqi Feng ◽  
Tianshu Zhang

Purpose The purpose of this paper is to provide a better understanding of the driving forces and structural changes of China as a market provider for Korea. This paper gives the answers for the following questions: How do China’s final demands trigger the growth of its imports from Korea? And what’s the impact of China’s final demands on the import in different industries? Design/methodology/approach Based on the Multi-Regional Input-Output model and World Input-Output Table database, this paper constructs the non-competitive imports input-output (IO) table of China to Korea. According to this table, we can calculate the induced imports coefficient and comprehensive induced import coefficients of China’s four final demands for imports from Korea in the 56 industries in China. Findings Among the four driving forces, the strongest one is changes in inventories and valuables. The impact of final consumption expenditure and fixed capital formation is much lower than that of changes in inventories and valuables, but they have a broader impact for the 56 industries. This paper finds out the China’s import induction of the final demands to Korea peaked in 2005 and 2010 and decreased greatly in 2014, so the position of China as market provider for Korea will no longer rise substantially, contrarily it will be in a steady state. Originality/value First, this paper constructs the non-competitive IO table to analyze the market provider issues between two countries and provides practical ways and methods for studies on the issues of imports and market provider. Second, this paper investigates the different roles of four final demands on driving force of China as market provider for Korea and the structural changes of China as a market provider for Korea among 56 industries from 2000 to 2014.


2013 ◽  
Vol 427-429 ◽  
pp. 133-136
Author(s):  
Qiang Song ◽  
Pu Zeng

The driving theory and the dynamic characteristics of small radius steering, medium radius steering and big radius steering is analyzed, and the simulation model is established under Matlab/Simulink. Then the track bulldozers steering performance of the three sheerings is simulated. The results show that, at different steering modes, the running states of the two sides driving motors are not the same, and the track driving forces of the two sides vary widely. The track driving force is great in the small radius steering model, while small in the medium and big radius steering models. The simulation results lay the foundation for dual-motor drive track bulldozers steering performance matching.


2018 ◽  
Vol 1 (2) ◽  
pp. 79-86 ◽  
Author(s):  
David P. Looney ◽  
Mark J. Buller ◽  
Andrei V. Gribok ◽  
Jayme L. Leger ◽  
Adam W. Potter ◽  
...  

ECTemp™ is a heart rate (HR)-based core temperature (CT) estimation algorithm mainly used as a real-time thermal-work strain indicator in military populations. ECTemp™ may also be valuable for resting CT estimation, which is critical for circadian rhythm research. This investigation developed and incorporated a sigmoid equation into ECTemp™ to better estimate resting CT. HR and CT data were collected over two calorimeter test trials from 16 volunteers (age, 23 ± 3 yrs; height, 1.72 ± 0.07 m; body mass, 68.5 ± 8.1 kg) during periods of sleep and inactivity. Half of the test trials were combined with ECTemp™’s original development dataset to train the new sigmoid model while the other was used for model validation. Models were compared by their estimation accuracy and precision. While both models produced accurate CT estimates, the sigmoid model had a smaller bias (−0.04 ± 0.26°C vs. −0.19 ± 0.29°C) and root mean square error (RMSE; 0.26°C vs. 0.35°C). ECTemp™ is a validated HR-based resting CT estimation algorithm. The new sigmoid equation corrects lower CT estimates while producing nearly identical estimates to the original quadratic equation at higher CT. The demonstrated accuracy of ECTemp™ encourages future research to explore the algorithm’s potential as a non-invasive means of tracking CT circadian rhythms.


Author(s):  
Yu. A. Taran ◽  
A. V. Kozlov ◽  
A. L. Taran

The aim of the work is to consider the mechanism of clogging the pores of the filter unit by small particles from the flow of filtrate inside them. Theoretical ideas about the process of filtering with the deposition of small particles from the filtrate on the pore walls and attribution of its fundamentals to restructuring from the original structure to the final structure allow to describe the process of clogging the pores using well studied concepts of known processes with phase transformations (in particular, crystallization). Based on this analogy and the approach to the description of the transformation of the "old" structure into a "new" one in time, using experimental data and their processing we calculated the rate of nucleation of the sediment centers (ωnucl), the linear (υlin) and volumetric rates of sediment plaques growth in the pores of the filter unit at different values of the process driving force, at different pressure difference in the system, and at different concentrations of solid particles in the suspension. Interpolation and extrapolation dependences were obtained for analyzing the mechanisms of sediments formation and growth for determining and calculating these (ωnucl, υlin) rates. Using the concepts of nonequilibrium thermodynamics to assess the influence of the driving forces we studied their influence (changes in the concentration of solid particles in the filtrate suspension and pressure drop across the filtering layer) on the dynamics of the filtration process. Using the data obtained it is possible to find the degree of clogging of through pores, which determines the filtration conditions, the filter septum type, and the filter overall dimensions.


Author(s):  
Yan Li ◽  
Shuchao Zhang ◽  
Ning Mei

In this paper, the anti-gravity flow in the spiral micro-channel on the surface of horizontal tube was visualized by the three-dimensional ultra-microscope system. The coupling relationship between the driving force and the flow was studied by Onsager reciprocal relations. The results show that the formation of the anti-gravity flow in the spiral micro-channel on the surface of horizontal tube is impacted by the combining effect of several factors, such as the capillary pressure, wettability, temperature, and bubbles.


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