scholarly journals The measurement of ground motion of destructive earthquakes

1963 ◽  
Vol 53 (2) ◽  
pp. 419-437
Author(s):  
D. E. Hudson
Keyword(s):  
United States ◽  
Transient Response ◽  
Strong Motion ◽  
The United States ◽  
Geodetic Survey ◽  
Natural Period ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
The World ◽  
Structural Engineers

abstract The need for a greatly expanded network of strong-motion accelerographs throughout the seismic regions of the world is stressed. A summary of the characteristics of currently available strong-motion accelerographs is presented, and the design details are given for an instrument suitable for acquiring the basic data needed by structural engineers for earthquake resistant design. It is shown that for such an instrument, the natural period must be less than 0.1 seconds, and that the recording speed must be at least 1 cm/sec. The critical nature of the inertia starting device is discussed, and some information is given on the transient response of the standard pendulum starter used in the United States Coast and Geodetic Survey Strong-Motion Accelerograph. The use of simpler, non-time-recording instruments such as the U.S.C.G.S. Seismoscope to supplement the accelerograph network is described.

Proposal of orientation-independent measure of intensity for earthquake-resistant design

2021 ◽  
pp. 875529302110382
Author(s):  
Alan Poulos ◽  
Eduardo Miranda
Keyword(s):  
United States ◽  
Ground Motion ◽  
The United States ◽  
Design Codes ◽  
Intensity Measure ◽  
Independent Measure ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
Ground Motion Records ◽  
Structural Engineers

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.

Site-dependent spectra for earthquake-resistant design

1976 ◽  
Vol 66 (1) ◽  
pp. 221-243 ◽  
Author(s):  
H. Bolton Seed ◽  
Celso Ugas ◽  
John Lysmer
Keyword(s):  
United States ◽  
Statistical Analysis ◽  
Ground Motion ◽  
The United States ◽  
Design Criteria ◽  
Earthquake Resistant Design ◽  
Geological Conditions ◽  
Earthquake Resistant ◽  
Ground Motion Records ◽  
Spectral Shapes

abstract The paper presents the results of a statistical analysis of the spectral shapes of 104 ground-motion records obtained from 23 earthquakes, mostly in the western part of the United States. The analysis shows clear differences in spectral shapes for different soil and geological conditions, indicating the need for consideration of these effects in selecting earthquake-resistant design criteria.

Sex Differences in Mass Media Preferences Across Four Asian Countries

2011 ◽  
Vol 23 (4) ◽  
pp. 186-191 ◽  
Author(s):  
Malini Ratnasingam ◽  
Lee Ellis
Keyword(s):  
United States ◽  
Sex Differences ◽  
Mass Media ◽  
The United States ◽  
Female Students ◽  
The Internet ◽  
Evolutionary Explanation ◽  
Asian Countries ◽  
The World ◽  
Media Preferences

Background. Nearly all of the research on sex differences in mass media utilization has been based on samples from the United States and a few other Western countries. Aim. The present study examines sex differences in mass media utilization in four Asian countries (Japan, Malaysia, South Korea, and Singapore). Methods. College students self-reported the frequency with which they accessed the following five mass media outlets: television dramas, televised news and documentaries, music, newspapers and magazines, and the Internet. Results. Two significant sex differences were found when participants from the four countries were considered as a whole: Women watched television dramas more than did men; and in Japan, female students listened to music more than did their male counterparts. Limitations. A wider array of mass media outlets could have been explored. Conclusions. Findings were largely consistent with results from studies conducted elsewhere in the world, particularly regarding sex differences in television drama viewing. A neurohormonal evolutionary explanation is offered for the basic findings.

Sandra Ramos Revisited

2020 ◽  
Vol 2 (4) ◽  
pp. 32-54
Author(s):  
Silvia Spitta
Keyword(s):  
United States ◽  
The United States ◽  
Ancient Greek ◽  
Graphic Arts ◽  
Left Behind ◽  
The World ◽  
The Usa ◽  
Political Choices ◽  
The Rich

Sandra Ramos (b. 1969) is one of the few artists to reflect critically on both sides of the Cuban di-lemma, fully embodying the etymological origins of the word in ancient Greek: di-, meaning twice, and lemma, denoting a form of argument involving a choice between equally unfavorable alternatives. Throughout her works she shines a light on the dilemmas faced by Cubans whether in Cuba or the United States, underlining the bad personal and political choices people face in both countries. During the hard 1990s, while still in Havana, the artist focused on the traumatic one-way journey into exile by thousands, as well as the experience of profound abandonment experienced by those who were left behind on the island. Today she lives in Miami and operates a studio there as well as one in Havana. Her initial disorientation in the USA has morphed into an acerbic representation and critique of the current administration and a deep concern with the environmental collapse we face. A buffoonlike Trumpito has joined el Bobo de Abela and Liborio in her gallery of comic characters derived from the rich Cuban graphic arts tradition where she was formed. While Cuba is now represented as a rotten cake with menacing flies hovering over it ready to pounce, a bombastic Trumpito marches across the world stage, trampling everything underfoot, a dollar sign for a face.

The Unquiet Frontier

2017 ◽  
Author(s):  
Jakub J. Grygiel ◽  
A. Wess Mitchell ◽  
Jakub J. Grygiel ◽  
A. Wess Mitchell
Keyword(s):  
United States ◽  
The United States ◽  
Great Powers ◽  
Global Order ◽  
American Power ◽  
Alliance Networks ◽  
Effective Strategies ◽  
The World ◽  
The Baltic ◽  
Critical Regions

From the Baltic to the South China Sea, newly assertive authoritarian states sense an opportunity to resurrect old empires or build new ones at America's expense. Hoping that U.S. decline is real, nations such as Russia, Iran, and China are testing Washington's resolve by targeting vulnerable allies at the frontiers of American power. This book explains why the United States needs a new grand strategy that uses strong frontier alliance networks to raise the costs of military aggression in the new century. The book describes the aggressive methods which rival nations are using to test American power in strategically critical regions throughout the world. It shows how rising and revisionist powers are putting pressure on our frontier allies—countries like Poland, Israel, and Taiwan—to gauge our leaders' commitment to upholding the American-led global order. To cope with these dangerous dynamics, nervous U.S. allies are diversifying their national-security “menu cards” by beefing up their militaries or even aligning with their aggressors. The book reveals how numerous would-be great powers use an arsenal of asymmetric techniques to probe and sift American strength across several regions simultaneously, and how rivals and allies alike are learning from America's management of increasingly interlinked global crises to hone effective strategies of their own. The book demonstrates why the United States must strengthen the international order that has provided greater benefits to the world than any in history.

Bringing the Real World of Science to Children: A Partnership of the American Museum of Natural History and the City University of New York

2008 ◽  
Vol 12 (1) ◽  
Author(s):  
Anthony G Picciano ◽  
Robert V. Steiner
Keyword(s):  
United States ◽  
New York ◽  
Natural History ◽  
Local Governments ◽  
Compulsory Education ◽  
Development Program ◽  
The United States ◽  
American Museum ◽  
The World ◽  
The City

Every child has a right to an education. In the United States, the issue is not necessarily about access to a school but access to a quality education. With strict compulsory education laws, more than 50 million students enrolled in primary and secondary schools, and billions of dollars spent annually on public and private education, American children surely have access to buildings and classrooms. However, because of a complex and competitive system of shared policymaking among national, state, and local governments, not all schools are created equal nor are equal education opportunities available for the poor, minorities, and underprivileged. One manifestation of this inequity is the lack of qualified teachers in many urban and rural schools to teach certain subjects such as science, mathematics, and technology. The purpose of this article is to describe a partnership model between two major institutions (The American Museum of Natural History and The City University of New York) and the program designed to improve the way teachers are trained and children are taught and introduced to the world of science. These two institutions have partnered on various projects over the years to expand educational opportunity especially in the teaching of science. One of the more successful projects is Seminars on Science (SoS), an online teacher education and professional development program, that connects teachers across the United States and around the world to cutting-edge research and provides them with powerful classroom resources. This article provides the institutional perspectives, the challenges and the strategies that fostered this partnership.

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