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PubMed · 2281883

Fractal system--a time domain approach.

H H Sun·A Charef
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Abstract

A method to analyze the fractal system in the time domain is presented so that the dynamic behavior of the system can be studied. The fractal system is represented by a set of linear time-varying differential equations whose order depends on the order of the system under non-fractal condition. Four different types of fractal system are considered and their solutions in the time domain are presented. These analyses show that the fractal system is dynamically more stable with smooth changes of magnitude and less oscillatory than the non-fractal system. Examples of the physiological system of the conduction pathways in the heart and also the polarization phenomena of noble metal are presented to illustrate the phenomena.

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Bundle of HisComputer SimulationElectric ConductivityElectrodesFourier AnalysisHeart Conduction SystemHumansMaleMaterials TestingMathematical ComputingModels, TheoreticalPurkinje FibersReference ValuesTime FactorsJournal Article

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H H Sun, A Charef. 1990. Fractal system--a time domain approach.. https://doi.org/10.1007/bf02368450

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Wilhelm His Jr. (1863-1934) was a Swiss-born cardiologist and anatomist. In 1893, he discovered the bundle of His-the specialized tissue in the heart that transmits the electrical impulses and helps synchronize contraction. He pioneered studies in cardiac conduction and coined the term "heart block," which he identified as the cause of Adams-Stokes disease. He was a professor of medicine at the University of Berlin, became the dean of medicine in 1918 and in 1928 was elected rector of the University of Berlin. Through his long clinical and teaching career he became better known for his work on gout and diseases of the joints. "Trench fever," or Werner-His disease, was also named after him. This report presents the life and work of Wilhelm His Jr., who was described by his colleagues as "a master of his profession, a great physician, investigator, and a well cultured gentleman."

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