Dielectric Loss Measurement Method based on the Energy Moment and Quasi-Periodic Interpolation

Harmonic analysis method for measurement of dielectric loss, due to the impact of fluctuations in grid frequency and higher harmonics, it is difficult to do the synchronous sampling, which reduces the accuracy of the measurements (especially the phase).In order to improve measurement accuracy, this paper presents a new method of calculation based on the energy moment of quasi-periodic interpolation algorithm. First, using a high frequency to sample the original signal, and then using the energy moment balance theory accurately measure the fundamental frequency, further calculating the integral period sampling rate and integral period samples, and last making integral period re-sampling and FFT calculation after interpolation. The simulation results show that this algorithm is high accuracy, good stability, less affected by the frequency fluctuation, harmonic proportion and initial phase.

Science, art and geometrical imagination

From the geocentric, closed world model of Antiquity to the wraparound universe models of relativistic cosmology, the parallel history of space representations in science and art illustrates the fundamental rôle of geometric imagination in innovative findings. Through the analysis of works of various artists and scientists like Plato, Dürer, Kepler, Escher, Grisey or the author, it is shown how the process of creation in science and in the arts rests on aesthetical principles such as symmetry, regular polyhedra, laws of harmonic proportion, tessellations, group theory, etc., as well as on beauty, conciseness and an emotional approach of the world.

Pulse Spectrum Analysis, a Faster and Easier Way to Predict Outcome of Sepsis?

In order to provide a faster and easier way for outcome prediction of sepsis, this study aimed to characterize the pattern of arterial pulse spectrum by a rat cecum ligation and puncture (CLP) model and explore whether specific harmonic components of pulse spectrum are associated with the mortality of CLP rats, followed by the comparison of accuracy between these specific variables and IL-6. Nineteen Sprague-Dawley rats receiving CLP were analyzed. Femoral artery of each rat was catheterized for blood pressure recording and blood sampling in the first 24 hours after CLP. The former was for off-line pulse spectrum analysis, and the latter for IL-6 assay. These rats were observed for 3-day mortality after CLP, and were divided into survivor or non-survivor groups. Differences of the hemodynamic profile, IL-6, and changes of the harmonics between the 2 groups were analyzed by using the Mann-Whitney test. Kaplan-Meier curves were constructed to characterize cumulative survival with the best prognostic cutoff point. The characteristic changes of pulse spectrum were different between survivors and non-survivors. The percentage differences of the 2nd harmonic proportion (C2) increased significantly from the 10th hour after CLP, and was higher in the non-survivors. Serum levels of IL-6 were also higher in the non-survivor group. Analyzed by Kaplan-Meier survival curve for 3-day mortality, C2 had a higher accuracy than IL-6 as a predictor. The pulse spectrum analysis may be applied to evaluate the prognosis of CLP rats, and the rapidly and highly elevated C2 harmonic had a strong association with the 3-day mortality of CLP rats.

Different Patterns of Pulse Spectrum Between Survivors and Non-survivors During Progressive Hemorrhage in Rats

Previous work from our laboratory has demonstrated that the percentage differences of 2nd (C2) and 3rd (C3) pulse harmonics related to Kidney and Spleen were both increased toward another steady state in rats after acute hemorrhage. Therefore, it is suggested that changes in pulse spectra might represent the ability of animals to survive a model of progressive hemorrhage. In this study, the difference of the pulse spectra patterns between survivors and non-survivors after progressive hemorrhage (by loss of 5%, 10% or 20% of the estimated blood volume) in anesthetized rats is determined. Seven rats, dead within 2 hours after a loss of 20% of the estimated blood volume hemorrhage, were defined as 'non-survivors'. The other eleven rats, more than 2 hours after hemorrhage, were defined as 'survivors'. Pulse waves of arterial blood pressure before and after the hemorrhage were measured in parallel to the pulse spectrum analysis. Data among different phases were analyzed using one-way analysis of variance (ANOVA) with Duncan's test for pairwise comparisons. Differences between survivor and non-survivor groups at each phase were analyzed using Student's t-test. A mixed-effects linear regression model was applied to evaluate the relationship in harmonics, which significantly differed between the two groups. The study results showed that in rats, during progressive hemorrhage, the percentage differences of 2nd harmonic proportion increased significantly; however, the result failed to show any significant difference between survivors and non-survivors. After the third blood withdrawal process, the percentage differences of 3rd harmonic proportion increased more significantly in the survivors. In addition, the percentage differences of 1st harmonic proportion related to the Liver for the survivor group was significantly lower than that of the non-survivors. After analysis with the mixed linear regression model, C3 and C1 demonstrated a linear regression relationship, and there existed significant differences between survivors and non-survivors. These results suggest that C3 might play an important role in physiology regarding surviving capability after progressive hemorrhage.

Pulse Spectrum Study on the Effect of Sie-Zie-Tang and Radix Aconiti

Extracts of the traditional Chinese fomlula Sie-Zie-Tang as well as one of its main components, Radix Aconiti were injected into rats intraperitoneally to observe pressure wave spectrum changes at the caudate artery. We found that Radix Aconiti decreased the C0 (DC term of the pulse), C5 and C6 (the harmonic proportions of the 5th and the 6th harmonic), but increased C2 and C3 (the harmonic proportions of the second and the third harmonic) significantly. For Sie-Zie-Tang, the increases of C2, C3, and C4 were accompanied by the decreasing of C0. The decreases of C5, C6 were small and not significant. The additional ingredients in the formula reduce toxic side effects (arrhythmia or heart failure caused by faster and stronger heart beat) due to Radix Aconiti. For human subjects, low dose Sie-Zie-Tang tends to normalize the Fourier components of the pressure wave. Orally taking the formula elevates the harmonic proportion of the harmonic that is lower than normal, but suppresses the higher one. Our result provides a possible mechanism for heart meridian related herbs. It strengthens heart beats, and normalizes energy distribution to different meridians. The study on Sie-Zie-Tang reveals another formula construction to reduce toxic side effects.

Harmonic Proportion and Palladio's "Quattro Libri"

In 1949, Wittkower proposed that musical harmonic ratios were a principle underlying Palladio's designs illustrated in the ground plans of Book II of the Quattro libri. This theory, expounded in Part IV of Wittkower's Architectural Principles in the Age of Humanism, has been widely accepted, despite the fact that his research was based on detailed analysis of only 8 of the 44 plans in Book II. In the present study, a systematic, quantitative analysis of all the plans in Book II of the Quattro libri is carried out to discover to what extent musical harmonic ratios were an important principle behind Palladio's ground plans. Our results show that Palladio did indeed have a definite preference for numbers which can be related in ratios corresponding to the standard musical intervals. However, he does not make any consistent attempt to render his designs completely harmonic. Only about two-thirds of all the dimensions in the Book II plans are numbers which can be incorporated into musical ratios. Palladio often made no attempt to make his published measurements accord with musical harmonies where this could have been done by minor alterations, such as insignificant changes in wall thicknesses. The actual buildings, too, show a preference for dimensions which can be related by harmonic ratios, although not quite to the extent of the plans published in the Quattro libri. A few, most notably the Villa Barbaro at Maser, are significantly more "harmonic" in the published versions than in reality. In view of Daniele Barbaro's well-known interest in harmonic proportion, it is significant that all the completely harmonic designs postdate Palladio's collaboration with Barbaro on the Vitruvius edition and the Villa at Maser. Most of the patrons of those designs closely based upon musical harmonies appear to have shared an interest in musical or architectural theory. While Palladio almost certainly used musical theory in some later designs, his dependence on musical harmonic proportion was by no means as great as Wittkower implied. Elsewhere, his preference for harmonic dimensions probably resulted either from his use of certain favorite room shapes, or from the practical advantages of using simple, easily divisible numbers.