bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimates of velocity structure and source depth using multiple P waves from aftershocks of the 1987 Elmore Ranch and Superstition Hills, California, earthquakes
Authors: Mori Jim 
Published: September 2021

Abstract
Event record sections, which are constructed by plotting seismograms from many closely spaced earthquakes recorded on a few stations, show multiple free-surface reflections (PP, PPP, PPPP) of the P wave in the Imperial Valley, California. The relative timing of these arrivals is used to estimate the strength of the P-wave velocity gradient within the upper 5 km of the sediment layer. Consistent with previous studies, a velocity model with a value of 1.8 km/sec at the surface increasing linearly to 5.8 km/sec at a depth of 5.5 km fits the data well. The relative amplitudes of the P and PP arrivals are used to estimate the source depth for the aftershock distributions of the Elmore Ranch and Superstition Hills main shocks. Although the depth determination has large uncertainties, both the Elmore Ranch and Superstition Hills aftershock sequences appear to have similar depth distribution in the range of 4 to 10 km.
Observations of the transition from linear polarization to complex polarization in short-period compressional waves
Authors: Menke William , Lerner-Lam Arthur 
Published: September 2021

Abstract
We measure the polarization of compressional waves from seismograms of chemical explosion of the Ontario-New York-New England refraction experiment recorded by the seven element ECO array in the New York Adirondack mountains. After careful instrument calibration, a precision of about 5° is achieved in measuring the azimuth of the compressional wave polarization direction. The azimuth of the polarization of the onset of the P wave differs from the geometrical source-receiver azimuth by as much as 20°, possible due to deflection of the first-arriving ray by lateral variation in crustal structure. Shortly after the onset of P, the polarization changes from the linear polarization expected of a compressional wave to become very complex. The time of this transition increases with source-receiver distance, from about 0.4 to 0.5 sec at 50 km distance and 0.7 to 0.8 sec at 150 km distance. The complex polarization may be due to the arrival of strongly scattered waves that have propagated mainly in the shallow crust, which would imply that the upper 1 to 2 km of the crust is particularly heterogeneous.
Behavior of near-source peak horizontal and vertical ground motions over SMART-1 Array, Taiwan
Authors: Niazi M. , Bozorgnia Y. 
Published: September 2021

Abstract
Over 700 accelerograms recorded from 12 earthquakes in northeast Taiwan have been analyzed for investigating the behavior of vertical and horizontal peak and spectral ground motion in the near-source region. Peak horizontal and vertical ground acceleration (PGA), velocity (PGV), and displacement (PGD) in the range of engineering interest have been subjected to a two-step nonlinear regression procedure in terms of magnitude and hypocentral distance.
In comparison with a number of other studies of global PGA observations, our predictions show lower far-field attenuation, lower near-source amplitudes, higher magnitude saturation for the vertical component, lower magnitude saturation for the horizontal component, and higher magnitude scaling.
The 2 / 3 ratio of vertical to horizontal ground motion, commonly used in engineering applications, may be unconservative in the very near-field for high-frequency ground motion. It falls below 1 / 2 at distances greater than 50 km. The same ratio for PGV and PGD tends to increase with distance, the latter at a faster rate. For SMART-1 data the major source of uncertainty appears to be inter-event rather than intra-event randomness. The predominance of the inter-event uncertainty in ground motions near the source is expected to be a characteristic of all dense arrays.
Criticism of some forecasts of the national earthquake prediction evaluation council
Authors: Savage J. C. 
Published: September 2021

Abstract
The Working Group on California Earthquake Probabilities has assigned probabilities for rupture in the interval from 1988 to 2018 to various segments of the San Andreas fault on the basis of the lognormal distribution of recurrence times of characteristic earthquakes postulated by Nishenko and Buland (1987). I question the validity of those probabilities on the basis of three separate arguments: (1) The distributions of recurrence times of the four, best-observed, characteristic-earthquake sequences are each only marginally consistent with the Nishenko - Buland Iognormal distribution. (2) The range of possible 30-year conditional probabilities for many of the fault segments is so great due to uncertainty in the average recurrence time for that segment that the assigned probability is virtually meaningless. (3) The 1988 forecasts not subject to the foregoing objection are those in which there is a low probability of an earthquake in the near future (e.g., only a 5 per cent chance of rupture of the North Coast segment before the year 2049 and of the Carrizo segment before the year 2018). The same reasoning would assign only a 5 per cent chance of rupture before mid-1993 to the southern Santa Cruz Mountains segment, the segment that failed in October 1989. Finally, the forecast of the next Parkfield earthquake (95 per cent probability before 1993.0) by Bakun and Lindh (1985) depends upon an ad hoc explanation of the out-of-sequence 1934 earthquake. A less-contrived forecast would have assigned a conditional probability of about 60 ± 20 per cent to the 1985.0 to 1993.0 interval and 30 ± 15 per cent to the 1990.0 to 1993.0 interval.
Interactive processing to obtain interstation surface-wave dispersion
Authors: Dean E. A. , Keller G. R. 
Published: September 2021

AbstractA processing scheme for the analysis of surface-wave dispersion is presented. This scheme involves preprocessing seismograms, computing the interstation Green's function, and determining the self-consistent phase and group dispersion with standard errors for one or more events for a two-station path. Time-variable filtering is employed, based on group velocity that is computer-selected by the multiple filter technique and refined by phase matching iteration. The interstation Green's function is frequency filtered to remove spikes from the spectrum. The interstation group velocity, perturbed by standard errors and refined by phase matching, is used to determine phase velocity and its uncertainty. Self-consistency between phase and group velocity is obtained by a simultaneous least-squares method, which ensures the correct functional relation for the two dispersed velocities. The uncertainty in dispersion is computed from the covariance matrix of the simultaneous least-squares solution. The technique is evaluated by comparing the analyzed dispersion for a path along the Andean Cordillera with results employing other techniques.
Inversion of arrival times of microearthquake sources in the North Sea using a 3-D velocity structure and prior information. Part I. Method
Authors: Engell-Sørensen Lisbeth 
Published: September 2021

Abstract
A new method for earthquake source location and velocity structure determination is formulated based on the Bayes theory. The medium is represented by homogeneous layers with plane-dipping interfaces. Inversion of the arrival-time data yields the velocity parameters, the hypocenters, and the origin times of the earthquakes.
A linear combination of model parameters is included in the method, and the determination of the standard deviations of the estimated parameters is elaborated. The possibility of constraining a linear combination of two model parameters are used for the P-to-S velocity ratio. Because the travel time cannot be found analytically, the forward problem is solved numerically, namely, by two-point raytracing.
Damage potential of Loma Prieta ground motions
Authors: Krawinkler Helmut , Nassar Aladdin , Rahnama Mohsen 
Published: September 2021

Abstract
This article focuses on an engineering evaluation of the ground motions recorded during the Loma Prieta earthquake. Regression analysis is employed to evaluate the attenuation characteristics of the elastic and inelastic strength demands imposed by rock and alluvium ground motions on bilinear single degree of freedom (SDOF) systems. Several records are used to illustrate the large seismic demands generated by soft soil ground motions. Strength capacities of modern code-designed structures are compared to the strength demands in order to assess the damage potential of the Loma Prieta ground motions. The Cypress structure is used as an example to illustrate the application of simple demand / capacity concepts for an evaluation of structural performance.
An experimental investigation of retrofitted cripple walls
Authors: Shepherd R. , Delos-Santos E. O. 
Published: September 2021

Abstract
Extensive damage was experienced by wood-frame buildings during the Loma Prieta earthquake. A significant contributory factor was the collapse of cripple walls. This prompted the examination of the behavior of a group of full-scale retrofitted cripple walls subjected to in-plane cyclic loads. The results of investigating seven cripple walls, each 2 ft (0.61 m) high and 16 ft (5 m) long, are presented. Two are control panels, without retrofits. Two are strengthened with 1 by 6 inch (25.4 by 153 mm) braces. Two are retrofitted with 0.5 inch (12.7 mm) plywood and one with a steel strap tie. Stiffness, strength, and damping characteristics are summarized, together with cost aspects. It is shown that relatively cheap and straightforward modifications can substantially eliminate the vulnerability of many existing cripple walls to earthquake shaking.
Site amplification fromS-wave coda in the Long Valley caldera region, California
Authors: Mayeda Kevin , Koyanagi Stuart , Aki Keiiti 
Published: September 2021

AbstractFollowing the work of Phillips (1985), we have computed site amplification factors for coda waves at many sites in the Long Valley region in the eastern Sierra Nevada. We computed ratios of coda amplitudes measured at 15 stations in and around Long Valley caldera relative to a granitic site, MMPM, for six frequency bands centered at 1.5, 3.0, 6.0, 9.0, 12.0, and 15.0 Hz. All station sites located within the caldera experienced large ground motion amplification at 1.5 and 3.0 Hz, ranging between five and 17 times that of the reference site. However, at higher frequencies, these same sites exhibited significantly less amplification than the reference granite site. This is attributed to the competing effects of an impedance contrast between the basement rock and caldera fill and very high absorption in the caldera fill at high frequencies. Station MMLM, located on top of a volcanic plug, displayed the largest amplitudes of all the sites studied for frequencies between 9.0 and 15.0 Hz. A dike structure attached to the plug couples the basement rock to the surface. At high frequencies, the resulting large amplitudes at MMLM are not due to amplification resulting from a strong impedance contrast; rather, the absorption under this site is very low, perhaps lower than at the reference site, MMPM. Outside the caldera, another hard-rock site located at Devil's Postpile, MDPM, generally behaved like the reference site for all frequencies. The lowest amplifications observed came from a site outside the caldera, MDCM, located on thin pyroclastic ash deposits overlying granitic basement. This can be attributed to a dominance of absorption over the amplification caused by lower impedance of this layer. Variations among sites on similar surface geology may be due to small local variations in impedance and absorption under and adjacent to the site. The range in the spectral decay parameter, κ, between caldera and rock sites are comparable to results of Anderson and Hough (1984) for sites on alluvium and rock in the San Fernando region. These surprisingly different amplifications support the need for additional site-specific studies. Amplifications determined in this study for the frequency range 1.5 and 3.0 Hz correlate remarkably well with Eaton's (1990) residuals for duration magnitude, FMAG, and amplitude magnitude, XMAG, for the USGS northern California seismic array, further supporting the use of coda waves in determining site-specific amplification.
Near-source effects on regional seismograms: An analysis of the NTS explosions PERA and QUESO
Authors: Taylor Steven R. , Rambo John T. , Swift Robert P. 
Published: September 2021

Abstract
A comparative analysis of two closely spaced Nevada Test Site explosions, PERA and QUESO, is made to study the effects of near-source phenomena on regional-wave excitation. Although the two explosions were of similar size, burial depth, and only separated by 4 km, the 1 to 2 and 6 to 8 Hz regional-wave spectral ratio for QUESO is anomalously low (a factor of 10 smaller than that of PERA). Examination of the regional and close-in spectra for each event shows a remarkable similarity and suggests that QUESO has less low-frequency and more high-frequency energy than PERA. These observations may be caused by a 564 m3, funnel-shaped region filled with unconsolidated sand and a possible void directly above the QUESO detonation point. Close-in observations suggest that this region may have partially decoupled the up-going energy from QUESO, resulting in a reduction of the low-frequency energy. The high-frequency enhancement for QUESO may be due to the rapid loss of energy to nonlinear effects such as greater pore collapse and fracturing in the anomalous region. This resulted in the radiation of more impulsive, shorter-duration waveforms producing a higher corner frequency and less-rapid high-frequency spectral decay for QUESO. For PERA, the loss of energy to a two-wave system occurred more slowly and over a larger volume, resulting in a broader source pulse typical of explosions in porous materials. Comparison of shock radius versus time data suggests that the shock wave was strongly affected in the anomalous zone a few meters above the QUESO device. One-dimensional finite-difference calculations with and without a partial decoupling region within 8 m of the device are consistent with the observations. Although spallation was reduced for QUESO, simulations using a finite spall model indicate that the spall spectral peak should be centered at about 3 to 7 Hz and probably did not significantly contribute to the reduced spectral ratio. The remarkable similarity of the PERA/QUESO spectral ratios taken at distances of 90 m and 400 km suggests that the spectral characteristics of explosions are established in close proximity to the source. Although depth-dependent effects of attenuation acting at small strains may enhance the differences in spectral ratios between NTS explosions and western U.S. earthquakes, these effects are probably secondary to the high-pressure, high strain-rate dynamic material response to the radiated explosion shock wave. These observations point out the importance of up-going energy on the generation of regional phases from explosions. Because of reduced overburden pressures above the detonation point, large nonlinear deformations predominate in this region and appear to affect all of the signals except perhaps the very initial part of the Pn waveform.
Information Services in Evidence Based Medical Education: A Review of Implementation Trends
Authors: Khani Sedigheh , Panahi Sirous , Pirsalehi Ali , Pourabbasi Ata 
Published: September 2021

Objective – Evidence based medical education requires supportive information services to facilitate access to the needed educational evidence. Information services designed specifically for evidence based medical education are limited or locally developed for educational units. For librarians to have an opportunity to cooperate efficiently with medical educators in evidence based medical education, they require an empirical prototype for transmission of clinical evidence at the right place and the right time. Therefore, there is a need to recognize types of information services which support evidence based medical education. The purpose of this review is to identify implementation trends of evidence based educational information services.
Methods – We found related studies by implementing search strategies in PubMed, EMBASE, Web of Science, Scopus, LISTA, and Google Scholar with keywords like: evidence based medical education, information services, and library services. We used reference-checking and citation-checking of related articles for completing the process of locating relevant articles. After employing inclusion and exclusion criteria, we selected 11 articles for inclusion in the review and analyzed them using a narrative review technique.
Results – After analyzing the results of the included studies, we identified two elements categorized as program development and five elements categorized as implementation trend. Prerequisites of program and the process of designing were essential parts of program development of information services. Schedule and type of access, how to receive educational-clinical questions, information services types, responding time, and providing evidence based outputs were the elements of the implementation process of educational supported information services.
Conclusion – Designing an evidence based educational information service strongly depends on the information needs of learners at each educational level. Schedule and type of access to information service, time of responding to the received query, and preparation of evidence based output are essential factors in designing practical educational-developed information services.
May I Borrow a Stapler? Is This All Students Ask at the Service Desk in a University Library?
Authors: Lamøy Liv Inger , Kilvik Astrid 
Published: September 2021

Objective – The objective of the study is to increase the knowledge about what questions students ask at the library desk and what the purpose is of their use of the desk. Our focus has been on the physical meetings with the students. The aim is to contribute to the discussion on the future development of the library service desk.
Methods – We recorded questions asked at the desks to explore how students use the library service desks. The recording, where library staff sorted questions into predefined categories, took place over four weeks between the years 2017–2018.
Results – Our recording showed that 63% of the questions asked at the library service desks were about loan services, document delivery, and access to physical and electronic collections. Practical things such as opening hours, lost and found items, and the location of the group study rooms, accounted for 16% of questions. Questions about information technology (IT) made up 8% of questions. Finally, the results showed that 8% of the questions from the four weeks of counting were counselling and guidance questions, and 2% were about literature lists, reference management, and reference management tools. We found more questions about counselling and guidance in the spring weeks and more practical questions in the fall. We did not find any clear connection between the number of questions and the size of the branch libraries.
Conclusion – By conducting this study, we have learned more about why students use the library desk. Our study shows that students come to the library desk to ask about a lot more than just borrowing staples. The results from the study will inform the development of the library desk service going forward.
Students Experience Cognitive and Emotional Responses to Academic Library Spaces
Authors: Bussell Hilary 
Published: September 2021

A Review of:
Mei, X. Y., Aas, E., & Eide, O. (2020). Applying the servicescape model to understand student experiences of a Norwegian academic library. Library & Information Science Research, 42(4), Article 101051. https://doi.org/10.1016/j.lisr.2020.101051
Abstract
Objective – To understand how the physical environment of an academic library influences user behaviour.
Design – Qualitative explorative.
Setting – An academic library at a large university in Norway.
Subjects – Twelve bachelor’s and master’s students at a business school.
Methods – The researchers used a two-step approach, with the servicescape model from the marketing discipline serving as a theoretical framework. Subjects completed several tasks involving drawing and elaborating on their usage of the library space, utilizing a bird’s-eye floor plan. This was followed by semi-structured interviews to explore how subjects use and experience the library facilities.
Main Results – Students found it important to be physically comfortable and to have enough room for the items they need while studying. The library in this study was seen more as a place for studying than for social interactions, and while some subjects reported being motivated by seeing students around them studying, others said they are distracted by having other students in their sightline. The time of the semester appeared to influence user experience and satisfaction with the library space, with spaces conducive to group work desired at some points in the semester and with single seating preferred when individual exams are taking place.
Conclusion – The library’s physical environment triggers cognitive and emotional responses in users. These responses influence how frequently they visit the library and how well they are able to concentrate while there. Because academic library spaces have an impact on student learning, it is important to design libraries with user comfort in mind. Libraries should accommodate the different ways students work throughout the semester by providing flexible study space configurations.
The effectiveness of acromegaly treatment according to the Registry of patients with pituitary tumors in the Republic of Tatarstan
Authors: Vagapova G. R. , Pashaev B. Yu. , Ashimova R. R. , Khafizov A. R. , Mokhova Iu. V. 
Published: September 2021

Background: Acromegaly is a severe progressive neuroendocrine disease caused by chronic elevated concentrations of growth hormone and insulin-like growth factor 1 in individuals with completed physiological growth and leading to early disability and mortality. The Acromegaly Registry with its regular updates makes it possible to merge and systematize all the available information on the diseases, to assess the efficacy of treatment algorithms and to choose an optimal diagnostic and treatment strategy in a given territory.Aim: To evaluate the efficacy of various treatments for acromegaly based on the analysis of the regional Registry of patients with pituitary tumors in the Republic of Tatarstan.Materials and methods: The study was based on data from 217 patients with somatotropin producing pituitary adenomas entered in the Registry of patients with pituitary tumors in the Republic of Tatarstan as per January 2021. One hundred and eighty one (181 patients) with sufficient data to assess the remission rates and the disease course were included into the analysis.Results: Endonasal endoscopic adenomectomy as a first-line treatment has been performed in 93% (169/181) of the patients, with 34% of the cases (57/169) being in the full postoperative remission. The efficacy of surgical treatment depended on the tumor size, invasion grade and aggressiveness. A 1st generation long-acting somatostatin analog (octreotide) has been prescribed to 50% (91/181) of the patients (11 patients as first-line therapy and 80 patients after adenomectomy), with biochemical remission rate of 56% (51/91). Radiological treatment has been completed in 11,6% (21/181) of the patients. The complete remission rate after all treatment modalities (surgical, medical, and radiation therapy) was 60% (108/181).Conclusion: The effectiveness of treatment for acromegaly in the Republic of Tatarstan is comparable to that in the all-Russian and international registries. Nevertheless, 40% of the patients with acromegaly in the region do not have their disease biochemically controlled indicating the need to optimize drug treatment.