摘要:

A prototype electronic (analog) circuit has been built to mimic a nonlinear oscillator proposed a century ago by Helmholtz in order to account for combinational tones in the drumskin, and more recently by Thompson to account for ship stability to waves in windy situations and its potential and eventual capsize. Besides a careful discussion of elements and their expected performance, several tests have been used to assess the reliability of the prototype.

ISSN:0034-6748    

DOI:10.1063/1.1143237

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

A configuration of a ring‐type bluff body situated in a circular pipe is suggested as a design of a vortex flowmeter. Experiments were carried out to test a series of ring‐type bluff models, whose geometrical parameters are expressed in terms of the gap ratioG/Wand the slenderness ratioD¯/W, whereGdenotes the gap width between the outer edge of the ring and the pipe wall,Wdenotes the width of the ring, andD¯ denotes the mean diameter of the ring. Major efforts are focused upon a group of the ring‐type vortex shedders whose vortex shedding process is strongly influenced by the presence of the wall. Results obtained suggest the appropriate sizes of rings for which the vortex shedding frequency can be clearly measured either on the pipe wall or at the center of the pipe.

ISSN:0034-6748    

DOI:10.1063/1.1143238

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

A method of transforming a histogram of one variable into a histogram of another variable is presented. No assumptions are made regarding the nature of either the initial or final distributions. The superiority of the method over simple linear interpolation is demonstrated.

ISSN:0034-6748    

DOI:10.1063/1.1143208

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

A micropipetting device incorporating an ultrasonic pump is described, in which vibration motion on the side surface of a cylindrical piezoelectric vibrator plays the key role. A core tube surrounded by three bearings mounted at the central part of the rotor operates essentially for the pump function. The tube‐type pipetting device has the merits of transportation of a minute, highly precise amount of liquid because of the electrically controllable characteristics.

ISSN:0034-6748    

DOI:10.1063/1.1143209

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

We describe a novel design for a cryogenic sample manipulator to be used for angle‐resolved surface investigations in an ultrahigh vacuum system. Azimuthal rotation of a sample in thermal contact with a closed‐cycle helium refrigerator is achieved by rotation of the heat shield that surrounds the cold finger of the refrigerator.

ISSN:0034-6748    

DOI:10.1063/1.1143210

出版商:AIP    

年代:1992

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1143798

出版商:AIP    

年代:1992

数据来源: AIP