INTERACTIONS BETWEEN TWO SEDIMENTING PARTICLES WITH DIFFERENT SIZES

IntroductionParticulateflowsarecommonlyencounteredinvariousnaturalphenomenaandindustrialprocesses,suchasinthechemicalandpetroleumindustries,thesedimentationofparticlesisawayofseparatingparticlesfromfluid ,aswellasawayofseparatingparticleswithdifferentsettlingspeedsfromeachother[1].Animportantaspectoftheseflowsisparticlepairinteraction ,whichisfundamentalmechanismsthatenterstronglyintoallpracticalapplicationsofparticulateflows.Problemofthesedimentationoftwoequalparticleshasbeenpreviouslystudied…     

UZAWA TYPE ALGORITHM BASED ON DUAL MIXED VARIATIONAL FORMULATION

ＩｎｔｒｏｄｕｃｔｉｏｎＦｏｒｔｈｅｓｏｌｕｔｉｏｎｏｆｔｈｅｅｌａｓｔｉｃｐｒｏｂｌｅｍ ,ｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔａｄｖａｎｔａｇｅｏｆｔｈｅｍｉｘｅｄｆｉｎｉｔｅｅｌｅｍｅｎｔｍｅｔｈｏｄｓｌｉｅｓｉｎｔｈｅｃｏｍｐｕｔｉｎｇｏｆｓｔｒｅｓｓａｎｄｄｉｓｐｌａｃｅｍｅｎｔａｎｄｓｏｏｎｓｉｍｕｌｔａｎｅｏｕｓｌｙ .Ｆｏｒｔｈｅｃｏｎｔａｃｔｐｒｏｂｌｅｍｉｎｅｌａｓｔｉｃｉｔｙ ,ａｎｅｗｄｕａｌｍｉｘｅｄｖａｒｉａｔｉｏｎａｌｆｏｒｍｕｌａｔｉｏｎａｎｄｔｈｅｃｏｒｒｅｓｐｏｎｄｉｎ…     

The steady state in-plane response of a curved Timoshenko beam with internal damping

Summary The steady state in-plane response of a curved Timoshenko beam with internal damping to a sinusoidally varying point force or moment is determined by use of the transfer matrix approach. The method is applied to free-clamped non-uniform beams with circular, elliptical, catenary or parabolical neutral axis excited at the free end; the driving point impedance and force or moment transmissibility are calculated numerically and the influence of the varying cross-section and of the function expressing the neutral axis are studied.

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Übersicht Es werden ebene, stationäre Schwingungen eines gekrümmten Timoshenko-Balkens mit innerer Dämpfung, durch harmonische Punkt-Kräfte oder Punkt-Momente erregt, mit Hilfe von Übertragungsmatrizen berechnet. Diese Methode wird auf einseitig fest eingespannte, ungleichförmige Balken angewendet, deren neutrale Achse verschiedene Formen (Kreisbogen, Ellipsenbogen, Kettenlinie, Parabel) besitzt. Für den am freien Ende erregten Balken werden Erreger-Impedanz und Durchlässigkeit für Kraft und Moment ausgerechnet; die Einflüsse des veränderlichen Querschnittes und der Form der neutralen Linie werden diskutiert.

     

STABILITY CRITERIA IN TERMS OF TWO MEASURES FOR DELAY DIFFERENTIAL EQUATIONS

ＩｎｔｒｏｄｕｃｔｉｏｎＡｓｗｅｋｎｏｗ ,ｉｎｔｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆｔｈｅｐｒｏｐｅｒｔｉｅｓｏｆｓｏｌｕｔｉｏｎｓｆｏｒｎｏｎｌｉｎｅａｒｄｉｆｆｅｒｅｎｔｉａｌｅｑｕａｔｉｏｎｓ,ｔｈｅｍｅｔｈｏｄｏｆｖａｒｉａｔｉｏｎｏｆｐａｒａｍｅｔｅｒｓｉｓａｎｅｆｆｅｃｔｉｖｅｔｏｏｌｉｎｔｈｅｃａｓｅｔｈａｔｔｈｅｃｏｒｒｅｓｐｏｎｄｉｎｇｕｎｐｅｒｔｕｒｂｅｄｔｅｒｍｓａｒｅｌｉｎｅａｒｏｒｏｆｃｅｒｔａｉｎｓｍｏｏｔｈｎｅｓｓｔｈｏｕｇｈｔｈｅｙａｒｅｎｏｎｌｉｎｅａｒ.Ｏｎｔｈｅ…     

Impact and Prevention of Voice Problems in the Teaching Profession: Embracing the Consumers'' View

Teachers are vulnerable to developing voice problems due to their specific occupational demands during teaching. Information on how the teaching profession is impacted by voice problems and what the profession perceives to be useful information for preventing voice problems is important for health care service providers. A total of 122 subjects from the teaching profession (55 practicing teachers and 67 prospective teachers) were therefore surveyed to ascertain their perception of their voice condition and the impact of voice problems on their communication, social life, personal emotions, and occupation. The results showed that the practicing teachers perceived their voice to be significantly worse than the prospective teachers. In addition, the teachers also faced significantly more difficulties in their daily communication than the prospective teachers. These two groups of subjects believed that information on breathing exercises and specific vocal hygiene strategies would help them prevent voice problems.     

In memoriam: Prof. Dr. dr.h.c. Rolf Hosemann

Dr. h.c. Rolf Hosemann, the “father of the ideal paracrystal,” passed away in Berlin on September 28, 1994, in his 83rd year. Rolf Hosemann was born in 1912 at Rostock on the Baltic Sea. He studied physics at Marburg and Freiburg, in Germany. In 1939 he obtained qualifications as a university teacher upon a “Habilitationsschrift” about the small-angle x-ray scattering of cellulose. In 1950 he laid the foundation to his theory of ideal paracrystals making wide use of convolution integrals as introduced into x-ray crystallography by P. P. Ewald. M. V. Laue was so much impressed by Hosemann's papers that he asked him to join the Fritz-Haber-Institut at Berlin-Dahlem as a staff member. It was there that Hosemann compiled his extensive work of more than 370 papers. Hosemann taught a large number of students. More than ten among them became university professors.     

ASMS members John Fenn and Koichi Tanaka share Nobel: The world learns our “secret”

Editorial

ASMS members John Fenn and Koichi Tanaka share Nobel: The world learns our “secret”     

Method of equilibrium differential equation for analysis of strength of large deflection drill string

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