High Rayleigh wave phase velocities for the New Delhi, India-Lahore, Pakistan profile

1966 ◽  
Vol 56 (5) ◽  
pp. 1137-1145
Author(s):  
V. G. Gabriel ◽  
John T. Kuo
Keyword(s):  
Phase Velocity ◽  
Structural Model ◽  
Great Circle ◽  
New Delhi ◽  
Indian Shield ◽  
Phase Velocities ◽  
Local Geology ◽  
Using Data ◽  
Great Circle Path ◽  
High Phase

Abstract Phase velocities were determined for the New Delhi-Lahore profile by using data from these two stations and earthquakes located approximately on the great circle path through the stations. The phase velocities were found to be higher than those expected for normal continental structures and somewhat similar to those found by Brune and Dorman (1963) for the Canadian shield. A structural model, based on the phase velocity values of the CANSD model given by Brune and Dorman (1963) and consistent with the local geology, was evaluated and is presented herewith as the INDSD model. It is postulated that high phase velocity values in the Lahore-New Delhi profile indicate the shield character of the crustal structure along the profile, as an extension of the Indian shield located south and southeast of it.

A crust-mantle profile from Mould Bay, Canada, to Tucson, Arizona

1968 ◽  
Vol 58 (6) ◽  
pp. 1821-1831
Author(s):  
A. J. Wickens ◽  
K. Pec
Keyword(s):  
Phase Velocity ◽  
Upper Mantle ◽  
Love Wave ◽  
Great Circle ◽  
Careful Selection ◽  
Precambrian Shield ◽  
Phase Velocities ◽  
Wave Phase ◽  
Adjacent Segments ◽  
Great Circle Path

ABSTRACT Love-wave phase velocities were determined for five adjacent segments of a 5000 kilometer great circle path from Mould Bay, Canada, to Tucson, Arizona. Mean-phase velocity curves were obtained from curves based on reciprocal data, thus minimizing the detrimental effects of non-parallel layering. By careful selection and precise treatment of the data over relatively short distances (800 km), detail hitherto suppressed has been retained. Finally, by using reciprocal seismograms, the effect of sloping interfaces was observed. The crustal and upper mantle models obtained indicate significant differences in structure between different provinces of the Precambrian Shield.

Finite-Difference Modeling and Characteristics Analysis of Love Waves in Anisotropic-Viscoelastic Media

2021 ◽  
Author(s):  
Shichuan Yuan ◽  
Zhenguo Zhang ◽  
Hengxin Ren ◽  
Wei Zhang ◽  
Xianhai Song ◽  
...  
Keyword(s):  
Finite Difference ◽  
Phase Velocity ◽  
Velocity Dispersion ◽  
Love Waves ◽  
Velocity Anisotropy ◽  
Viscoelastic Media ◽  
Phase Velocities ◽  
Phase Velocity Dispersion ◽  
Anisotropic Elastic ◽  
Attenuation Anisotropy

ABSTRACT In this study, the characteristics of Love waves in viscoelastic vertical transversely isotropic layered media are investigated by finite-difference numerical modeling. The accuracy of the modeling scheme is tested against the theoretical seismograms of isotropic-elastic and isotropic-viscoelastic media. The correctness of the modeling results is verified by the theoretical phase-velocity dispersion curves of Love waves in isotropic or anisotropic elastic or viscoelastic media. In two-layer half-space models, the effects of velocity anisotropy, viscoelasticity, and attenuation anisotropy of media on Love waves are studied in detail by comparing the modeling results obtained for anisotropic-elastic, isotropic-viscoelastic, and anisotropic-viscoelastic media with those obtained for isotropic-elastic media. Then, Love waves in three typical four-layer half-space models are simulated to further analyze the characteristics of Love waves in anisotropic-viscoelastic layered media. The results show that Love waves propagating in anisotropic-viscoelastic media are affected by both the anisotropy and viscoelasticity of media. The velocity anisotropy of media causes substantial changes in the values and distribution range of phase velocities of Love waves. The viscoelasticity of media leads to the amplitude attenuation and phase velocity dispersion of Love waves, and these effects increase with decreasing quality factors. The attenuation anisotropy of media indicates that the viscoelasticity degree of media is direction dependent. Comparisons of phase velocity ratios suggest that the change degree of Love-wave phase velocities due to viscoelasticity is much less than that caused by velocity anisotropy.

Geographical interpretation of measurements of average phase velocities of surface waves over great circular and great semi-circular paths

1964 ◽  
Vol 54 (2) ◽  
pp. 571-610
Author(s):  
George E. Backus
Keyword(s):  
Spherical Harmonics ◽  
Rayleigh Waves ◽  
Seismic Station ◽  
Great Circle ◽  
Explicit Formulas ◽  
Phase Velocities ◽  
Rapid Accumulation ◽  
Generalized Spherical Harmonics ◽  
Geographical Position ◽  
The Difference

ABSTRACT If the averages of the reciprocal phase velocity c−1 of a given Rayleigh or Love mode over various great circular or great semicircular paths are known, information can be extracted about how c−1 varies with geographical position. Assuming that geometrical optics is applicable, it is shown that if c−1 is isotropic its great circular averages determine only the sum of the values of c−1 at antipodal points and not their difference. The great semicircular averages determine the difference as well. If c−1 is anisotropic through any cause other than the earth's rotation, even great semicircular averages do not determine c−1 completely. Rotation has negligible effect on Love waves, and if it is the only anisotropy present its effect on Rayleigh waves can be measured and removed by comparing the averages of c−1 for the two directions of travel around any great circle not intersecting the poles of rotation. Only great circular and great semicircular paths are considered because every earthquake produces two averages of c−1 over such paths for each seismic station. No other paths permit such rapid accumulation of data when the azimuthal variations of the earthquakes' radiation patterns are unknown. Expansion of the data in generalized spherical harmonics circumvents the fact that the explicit formulas for c−1 in terms of its great circular or great semicircular integrals require differentiation of the data. Formulas are given for calculating the generalized spherical harmonics numerically.

Projection Bias in Catalog Orders

2007 ◽  
Vol 97 (4) ◽  
pp. 1217-1249 ◽  
Author(s):  
Michael Conlin ◽  
Ted O'Donoghue ◽  
Timothy J Vogelsang
Keyword(s):  
Field Data ◽  
Structural Model ◽  
Cold Weather ◽  
Change Over Time ◽  
Laboratory Evidence ◽  
Return Probability ◽  
Projection Bias ◽  
Using Data ◽  
Over Time

Evidence suggests that people understand qualitatively how tastes change over time, but underestimate the magnitudes. This evidence is limited, however, to laboratory evidence or surveys of reported happiness. We test for such projection bias in field data. Using data on catalog orders of cold-weather items, we find evidence of projection bias over the weather—specifically, people's decisions are overinfluenced by the current weather. Our estimates suggest that if the order-date temperature declines by 30°F, the return probability increases by 3.95 percent. We also estimate a structural model to measure the magnitude of the bias. (JEL D12, L81)

Using social distancing technology in hotels: a social exchange perspective

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Cristian Morosan ◽  
Agnes DeFranco
Keyword(s):  
Social Exchange ◽  
Health Risks ◽  
Social Exchange Theory ◽  
Structural Model ◽  
Content Type ◽  
Privacy Concerns ◽  
Social Distancing ◽  
Using Data ◽  
Social Rewards

Purpose As social distancing procedures can be facilitated by various hotel technologies, the purpose of this paper is to investigate the extent to which consumers develop perceptions of value regarding the use of certain hotel technologies for social distancing in hotels. Design/methodology/approach Drawing from the social exchange theory, this study conceptualized the benefits of using technologies for social distancing, health risks, social rewards and privacy concerns as antecedents of value of using technologies for social distancing in hotels. The structural model was validated by using data from more than 1,000 nationwide US consumers. Findings Benefits and consumers’ privacy concerns of using technologies for social distancing in hotels were the strongest predictors of value. Social rewards also had a significant but relatively lower effect on value. Health risks was found to have no influence on value. Originality/value The study is the first to examine the role of technologies in mitigating the effects of coronavirus. Thus, it extends the information technology and hospitality literature by examining the role of these technologies in safeguarding individual and public health.

Do traveltimes in pulse‐transmission experiments yield anisotropic group or phase velocities?

Geophysics ◽  
1994 ◽  
Vol 59 (11) ◽  
pp. 1774-1779 ◽  
Author(s):  
Joe Dellinger ◽  
Lev Vernik
Keyword(s):  
Phase Velocity ◽  
Group Velocity ◽  
Elastic Constants ◽  
Near Field ◽  
Frequency Dispersion ◽  
Transversely Isotropic ◽  
Sh Waves ◽  
Phase Velocities ◽  
Pulse Transmission ◽  
Transmission Technique

The elastic properties of layered rocks are often measured using the pulse through‐transmission technique on sets of cylindrical cores cut at angles of 0, 90, and 45 degrees to the layering normal (e.g., Vernik and Nur, 1992; Lo et al., 1986; Jones and Wang, 1981). In this method transducers are attached to the flat ends of the three cores (see Figure 1), the first‐break traveltimes of P, SV, and SH‐waves down the axes are measured, and a set of transversely isotropic elastic constants are fit to the results. The usual assumption is that frequency dispersion, boundary reflections, and near‐field effects can all be safely ignored, and that the traveltimes measure either vertical anisotropic group velocity (if the transducers are very small compared to their separation) or phase velocity (if the transducers are relatively wide compared to their separation) (Auld, 1973).

scholarly journals A Structural Model of the Retail Market for Illicit Drugs

2017 ◽  
Vol 107 (3) ◽  
pp. 858-896 ◽  
Author(s):  
Manolis Galenianos ◽  
Alessandro Gavazza
Keyword(s):  
Illicit Drugs ◽  
Structural Model ◽  
Crack Cocaine ◽  
Retail Market ◽  
High Quality ◽  
Using Data ◽  
First Time ◽  
Relative Profitability

We estimate a model of illicit drugs markets using data on purchases of crack cocaine. Buyers are searching for high-quality drugs, but they determine drugs' quality (i.e., their purity) only after consuming them. Hence, sellers can rip off first-time buyers or can offer higher-quality drugs to induce buyers to purchase from them again. In equilibrium, a distribution of qualities persists. The estimated model implies that if drugs were legalized, in which case purity could be regulated and hence observable, the average purity of drugs would increase by approximately 20 percent and the dispersion would decrease by approximately 80 percent. Moreover, increasing penalties may raise the purity and affordability of the drugs traded by increasing sellers' relative profitability of targeting loyal buyers versus first-time buyers. (JEL D12, K42, L15, L65)

The Vector Function for Distance Travelled in Great Circle Navigation

2006 ◽  
Vol 60 (1) ◽  
pp. 158-164 ◽  
Author(s):  
Wei-Kuo Tseng ◽  
Hsuan-Shih Lee
Keyword(s):  
Linear Combination ◽  
Vector Function ◽  
Personal Computer ◽  
Great Circle ◽  
Departure Point ◽  
Easy Method ◽  
Vector Algebra ◽  
Elementary Knowledge ◽  
Vector Basis ◽  
Great Circle Path

Traditionally, on a great circle, the latitude or longitude of a waypoint is found by inspection. In this paper, using an elementary knowledge of vector algebra including linear combination of vectors and vector basis, we provide an easy method for finding the equation of a great circle path as a parameterized curve. By use of this vector function of distance travelled, the latitude and longitude of waypoints can be found based on the distance from departure point along a great circle. The approach is intended to appeal to the navigator who is interested in the mathematics of navigation and who, nowadays, solves his navigation problems with a personal computer.

scholarly journals ANALYTICAL CONSIDERATIONS OF DEVELOPING A PHENOTYPIC AGING MEASURE: THE CONCEPTUAL FRAMEWORK MUST COME FIRST!

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S579-S580
Author(s):  
Michelle Shardell ◽  
Michelle Shardell ◽  
Pei-Lun Kuo ◽  
Jennifer Schrack ◽  
Eleanor M Simonsick ◽  
...  
Keyword(s):  
Construct Validity ◽  
Latent Variable ◽  
Structural Model ◽  
Chronological Age ◽  
Model Framework ◽  
Domain Specific ◽  
Genes And Environment ◽  
Convergent Construct Validity ◽  
Baltimore Longitudinal Study ◽  
Using Data

Abstract We propose a latent structural model framework where phenotypic aging is a latent variable influenced by chronological age, genes and environment. Within this framework, phenotypic age influences aging-related outcomes and is reflected by latent domains of aging (body composition, energetics, homeostasis, and neural functioning) reflected by biomarkers. First, we validate the framework by selecting age-associated domain-specific biomarkers and assessing internal consistency and convergent construct validity (Cronbach’s alpha). Using data from the Baltimore Longitudinal Study of Aging, within-domain Cronbach’s alphas ranged from 0.80 to 0.92, supporting convergent construct validity. Second, we evaluate two broad methods for combining biomarkers into one phenotypic age measure customized to different objectives: 1) confirmatory factor analysis of chronological age-adjusted biomarkers to create a measure to identify pleiotropic genetic and environmental mechanisms, and 2) machine-learning methods to create a measure optimizing predictive and concurrent criterion validity. This framework will enable evaluation of candidate biological mechanisms of aging.

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