An advanced intensity measure for residual drift assessment of steel BRB frames

A new measure of ground motion intensity in the horizontal direction is proposed. Similarly to other recently proposed measures of intensity, the proposed intensity measure is also independent of the as-installed orientation of horizontal sensors at recording stations. This new measure of horizontal intensity, referred to as MaxRotD50, is defined using the maximum 5%-damped response spectral ordinate of two orthogonal horizontal directions and then computing the 50th percentile for all non-redundant rotation angles, that is, the median of the set of spectral ordinates in a range of 90°. This proposed measure of intensity is always between the median and maximum spectral ordinate for all non-redundant orientations, commonly referred to as RotD50 and RotD100, respectively. A set of 5065 ground motion records is used to show that MaxRotD50 is, on average, approximately 13%–16% higher than Rot50 and 6% lower than RotD100. The new measure of intensity is particularly well suited for earthquake-resistant design where a major concern for structural engineers is the probability that the design ground motion intensity is exceeded in at least one of the two principal horizontal components of the structure, which for most structures are orthogonal to each other. Currently, design codes in the United States are based on RotD100, and hence using MaxRotD50 for structures with two orthogonal principal horizontal components would result in a reduction of the ground motion intensities used for design purposes.

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Densities for stationary random sets and point processes

Advances in Applied Probability ◽

10.1017/s0001867800022552 ◽

1984 ◽

Vol 16 (02) ◽

pp. 324-346 ◽

Cited By ~ 19

Author(s):

Wolfgang Weil ◽

John A. Wieacker

Keyword(s):

Poisson Process ◽

Point Processes ◽

Convex Set ◽

Compact Convex ◽

Random Sets ◽

Intensity Measure ◽

Additive Functionals ◽

Compact Convex Set ◽

Classical Integral

For certain stationary random setsX, densitiesDφ(X) of additive functionalsφare defined and formulas forare derived whenKis a compact convex set in. In particular, for the quermassintegrals and motioninvariantX, these formulas are in analogy with classical integral geometric formulas. The case whereXis the union set of a Poisson processYof convex particles is considered separately. Here, formulas involving the intensity measure ofYare obtained.

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Research on the Ventilator Noise Sound Intensity Measure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.765-767.2113 ◽

2013 ◽

Vol 765-767 ◽

pp. 2113-2116

Author(s):

Rong Jie Wang ◽

Hong Wei Chen

Keyword(s):

Density Function ◽

Sound Pressure ◽

Sound Intensity ◽

Vibration Velocity ◽

Velocity Spectrum ◽

Practical Application ◽

Intensity Measure ◽

Spectrum Density ◽

Important Means ◽

Gradient Change

Noise measurement is the important means on the noise monitoring, evaluation and control.At present the error of sound pressure method widely used is larger. It adopts the method of double microphone in the method of sound intensity measurement,and uses acoustic pressure gradient change to approximately equal the particle vibration velocity, spectrum density function is obtained by using sound intensity analyzer,it computes integral for Spectrum density function that are sound intensity.In this paper, by measuring sound intensity of ventilator and comparing the numerical results and experimental results, it confirmed that the method is high precision, has practical application value.

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Densities for stationary random sets and point processes

Advances in Applied Probability ◽

10.2307/1427072 ◽

1984 ◽

Vol 16 (2) ◽

pp. 324-346 ◽

Cited By ~ 37

Author(s):

Wolfgang Weil ◽

John A. Wieacker

Keyword(s):

Poisson Process ◽

Point Processes ◽

Convex Set ◽

Compact Convex ◽

Random Sets ◽

Intensity Measure ◽

Additive Functionals ◽

Compact Convex Set ◽

Classical Integral

For certain stationary random sets X, densities Dφ (X) of additive functionals φ are defined and formulas for are derived when K is a compact convex set in . In particular, for the quermassintegrals and motioninvariant X, these formulas are in analogy with classical integral geometric formulas. The case where X is the union set of a Poisson process Y of convex particles is considered separately. Here, formulas involving the intensity measure of Y are obtained.

Download Full-text