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Leszak E. Patent US3342051A1 , published 1967-09-19, Apparatus and Process for Incremental Dieless Forming. Maidagan E., Zettler J., Bambach M., Rodríguez P. P., Hirt G. A new
Abstract
An incremental integral isoconversional method for the determination of activation energy as a function of the extent of conversion is presented. The method is based on the treatment of experimental data without their transformation so that the resulting values of activation parameters should not be biased. The method was tested for recovering the activation energies from simulated data and employed for the treatment of experimental data of the NiS recrystallisation.
[ 22 ]. Thus, Budrugeac et al. considered that LT method is not suitable to find the dependence of E = E ( α ) [ 22 ]. In this article, an incremental version of LT method, which is independent of the lower limit of integration, is proposed
Abstract
Large deviation results for Gaussian processes are presented. As an application, we obtain a functional limit result for small increments of a fractional Brownian motion. Lvy's modulus of continuity for a fractional Brownian motion is obtained as a special case.
The goal of this study was to determine whether traditional ergoespirometric incremental exercise testing carried out to the point of exhaustion could be useful in distinguishing the physiological profiles of elite runners that compete in races that lasted about 8 minutes versus those that lasted about 2 hours. Ten male marathon runners (performance time: 2:12:04, coefficient of variation (CV) = 2.33%) and 8 male 3000 m steeplechase runners (performance time: 8:37.83, CV = 2.12%) performed an incremental test on the treadmill (starting speed 10 km·h−1; increments, 2 km·h−1; increment duration, 3 min to exhaustion). Heart rate (HR), VO2, and lactate concentrations were measured at the end of each exercise level. At maximal effort, there were no differences between the groups regarding VO2max and maximal HR; however, the workload time, vVO2max and peak treadmill velocity were significantly higher in the 3000 m steeplechase group (p<0.05). At submaximal effort, there were no significant differences between groups for VO2 (ml·kg−1·min−1), HR, or lactate. Our results show that this type of testing was not sufficient for discriminating the physiological profiles of elite runners who competed in middle-distance versus long-distance events (e.g. in the marathon and the 3000 m steeplechase).
This paper describes a new mathematical approach for the analysis of HR (heart rate) and BL (blood lactate) curves during incremental exercise testing using a HR/BL curve and its derivatives, taking into account the native shape of all curves, without any linear approximation. Using this approach the results indicate the apperance of three characteristic points (A, B and C) on the HR/BL curve. The point A on the HR/BL curve which is the value that corresponds to the load (12.73 ± 0.46 km h−1) at which BL starts to increase above the resting levels (0.9 ± 0.06 mM), and is analogous to Lactate Turn Point 1 (LTP1). The point C on the HR/BL curve which corresponds to a BL of approximately 4mM, and is analogous to LTP2. The point B on the HR/BL curve, which corresponds to the load (16.32 ± 0.49 km h−1) at which the moderate increase turns into a more pronounced increase in BL. This point has not been previously recognized in literature. We speculate this point represents attenuation of left ventricular ejection fraction (LVEF) increase, accompained by the decrease in diastolic time duration during incremental exercise testing. Proposed mathematical approach allows precise determination of lactate turnpoints during incremental exercise testing.
Let X 1, X 2,… be independent, but not necessarily identically distributed random variables in the domain of attraction of a stable law with index 0<a<2. This paper uses M n=max 1 ? i ? n|X i| to establish a self-normalized law of the iterated logarithm (LIL) for partial sums. Similarly self-normalized increments of partial sums are studied as well. In particular, the results of self-normalized sums of Horváth and Shao[9]under independent and identically distributed random variables are extended and complemented. As applications, some corresponding results for self-normalized weighted sums of iid random variables are also concluded.
This study examined the cortisol response to incremental exercise; specifically to see if there was an increase in blood cortisol levels at low intensity exercise (i.e., <60% VO 2 intensity threshold) and determine whether a linear relationship existed between the blood cortisol responses and exercise of increasing workloads (i.e., intensity). Healthy, physically active young men (n=11) completed exercise tests involving progressive workload stages (3 min) to determine peak oxygen uptake responses (VO 2 ). Blood specimens were collected at rest and at the end of each stage and analyzed for cortisol. Results showed cortisol was significantly increased from resting levels at the end of the first exercise stage (80 W; 41.9±5.4% peak VO 2 ) and remained significantly elevated from rest until the exercise ended. Interestingly, however, the cortisol concentrations observed at 80 W through 200 W did not significantly differ from one another. Thereafter, during the final two stages of exercise the cortisol concentrations increased further (p<0.01). The subjects exceeded their individual lactate thresholds over these last two stages of exercise. Regression modeling to characterize the cortisol response resulted in significant regression coefficients (r=0.415 [linear] and r=0.655 [3 rd order polynominal], respectively; p<0.05). Comparative testing (Hotelling test) between the two regression coefficents revealed the polynominal model (sigmoidal curve) was the significantly stronger of the two (p=0.05). In conclusion, the present findings refute the concept that low intensity exercise will not provoke a significant change in blood cortisol levels and suggest the response to incremental exercise involving increasing exercise workloads (i.e., intensities) are not entirely linear in nature. Specifically, a sigmoid curve more highly accurately characterizes the cortisol response to such exercise.
Abstract
Practicing sensory tasks could result in two main perceptual outcomes. The first, and more widely documented, is perceptual learning referring to long-lasting improvement of perceptual thresholds. The second is perceptual deterioration, which is observed when the number of trials is increased within a training session or between closely spaced sessions. Recent results with visual texture discrimination show that these two processes inversely affect each other: decremental effects interfere with further learning, while efficient short practice results in a long-term learning effect in which performance decrements are practically eliminated. Further results show that sleep is necessary to preserve learning effects following short training and facilitates the decay of deterioration that normally results from extensive training. We suggest a theoretical link between perceptual deterioration and learning, assuming a system with saturating connectivity. Training strengthens task related connections, with further training leading to saturation of these connections along with strengthening of less efficient connections corresponding to accumulated noise in the network. Such saturation in network connectivity and reduction of signal-to-noise ratio consequently affects the readout of the network, causing deterioration in discrimination performance. Thus, best learning is achieved with short training sessions. Resistance to saturation is achieved by sleep-dependent consolidation of unsaturated connectivity. The different transfer properties of the performance decrements and increments allow us to identify local and global components of perceptual learning and their interactions. This suggests sleep-dependent consolidation mechanisms that induce modifications in higher brain areas that interact with local early visual networks to enable improvement of perceptual abilities.
