bluuebunny/crossref_metadata_2025 huggingface dataset:
Što još one žele? Razvoj nove skale za mjerenje suvremenih oblika seksizma
Authors: Šimac Bruno , Klasnić Ksenija
Published: September 2021

Predrasude prema ženama, u obliku seksizma, tradicionalno su bile okarakterizirane zagovaranjem strogih rodnih uloga. No, uslijed kulturnih i političkih promjena posljednjih desetljeća, otvorena diskriminacija prema ženama postaje društveno neprihvatljiva, a seksizam preuzima nove, suvremene oblike koji često prolaze nezapaženo, tajno i skriveno. Cilj je ovoga rada konstruirati i evaluirati novu Skalu suvremenog seksizma koja će objediniti nekoliko do sad konceptualno razdvojenih oblika suvremenog seksizma, kao i neke sadržaje koji do sad nisu bili uključeni u postojeće skale suvremenih oblika seksizma. Oslanjajući se na tri tipa konceptualno-operacionalnih razrada suvremenog seksizma – moderni seksizam Swim i suradnica (1995), neoseksizam Tougas i suradnika (1995) te ambivalentni seksizam Glicka i Fiske (1996), konceptualno i operacionalno su razrađeni suvremeni seksistički stavovi u četiri temeljne sadržajne domene: 1. nijekanje postojanja daljnje diskriminacije žena; 2. antagonizam spram zahtjeva žena; 3. ogorčenje zbog posebnih pogodnosti koje žene dobivaju samo zbog toga što su žene; te 4. zamjeranje ženama zbog „preosjetljivosti“ na seksizam i seksualno uznemiravanje. Istraživanje je provedeno metodom ankete na prigodnom uzorku od 402 studentice i studenta različitih sastavnica Sveučilišta u Zagrebu. Konačnu inačicu Skale suvremenog seksizma (SSS) čini 27 čestica, a skala predstavlja jednodimenzionalan mjerni konstrukt. Na temelju provedenih analiza autori zaključuju da je SSS instrument visoke pouzdanosti te zadovoljavajuće sadržajne, kriterijske i konstruktne valjanosti i sugeriraju neke daljnje smjernice za njegovo korištenje u anketnim istraživanjima.
ÜNİVERSİTE ÖĞRENCİLERİNİN ZORUNLU UZAKTAN EĞİTİMİN YÜRÜTÜLMESİNE İLİŞKİN ÖNERİLERİ
Authors: DEMİRBİLEK Nesip , ATİLA Fulya
Published: September 2021

Bu araştırmanın amacı, üniversite öğrencilerinin zorunlu uzaktan eğitimin yürütülmesine ilişkin görüşlerini belirlemektir. Araştırmada nitel araştırma yöntemlerinden durum çalışması deseni kullanılmıştır. Araştırmanın çalışma grubunun belirlenmesinde kolay örnekleme (easily accessible) tekniği kullanılmıştır. Araştırmanın amacı doğrultusunda, araştırma konusuyla ilgili bilgi sahibi olan uzaktan öğretim gören üniversite öğrencilerinin yer aldığı bir çalışma grubu belirlenmiştir. Bu araştırma için belirlenen çalışma grubunda, 2019-2020 eğitim-öğretim yılında uzaktan öğrenim gören Muş Alparslan Üniversitesinde 403, Bingöl Üniversitesinde 601 olmak üzere toplam 1004 üniversite öğrencisi yer almıştır. Çalışmada elde edilen verilerin analizinde “betimsel analiz ve içerik analizi” tekniğinden yararlanılmıştır. Araştırmanın bazı sonuçlarına göre; Coronavirüs (Covid-19) pandemisi nedeniyle uygulanmakta olan uzaktan eğitimin ilk uygulamalarında öğrenciler, akademisyenlerin anlayışlı ve esnek olmalarını, öğrenci ile iyi iletişim kurmalarını, süreci kolaylaştıran bir tutum içerisinde olmalarını önermişlerdir. Sınav sistemi ile ilgili olarak daha basit ve anlaşılır olması gerektiğini, sınavların ödev şeklinde olması gerektiğini, notların daha adaletli verilmesi gerektiğini savunmuşlardır. Uzaktan öğretimin canlı ders ve videolarla yürütülmesinin önemini ve gerektiğinde telafi eğitimleri yapılmasını çokça vurgulamışlardır. İnternet bağlantısı ve şebeke gibi sorunları olduğunu dile getirmişlerdir. Araştırma sonuçları doğrultusunda, evdeki eğitim kalitesinin arttırılması gerektiği önerilmektedir.
OKUL DIŞI ÖĞRENME ORTAMLARININ DEĞERLENDİRİLMESİ: YAPILANDIRMACI MÜZE ÖĞRENME ORTAMLARI ÖLÇEĞİNİN TÜRKÇEYE UYARLANMASI
Authors: DÖNMEZ İsmail , İDİN Şahin
Published: September 2021

Bu araştırmanın amacı, “Museum Constructivist Learning Environment Survey (M-CLES)” isimli ölçeğin Türkçeye uyarlanarak, geçerlilik ve güvenirlik çalışmasını yapmaktır. Ölçek uyarlamada ihtiyaç belirleme, izinlerin alınması, dil çevirisi, çeviri, çeviri karşılaştırma, geri çeviri, dil geçerliliği, pilot uygulama ve asıl uygulama adımları izlenmiştir. Araştırmaya bir bilim merkezini ziyaret eden, 123 (%62,1) kız, 75(%37,9) erkek olmak üzere 198 kişi katılmıştır. Katılımcılar 9-16 yaş grubu arasında 4.-10. sınıf öğrencileridir. Orijinal ölçek, 25 madde ve 5 boyuttan oluşmaktadır. Ölçeğin, KMO değeri 0,904 olarak hesaplanmıştır. Veriler toplandıktan sonra doğrulayıcı faktör analizi yapılmış (χ²/sd = 1.89, GFI = 87, IFI = .85, CFI = .92, NFI = .77 AGFI = .82, NGI = .85 ve RMSEA = .06) ve ölçeğin güvenirlik analizi için Cronbach’s Alfa iç güvenirlik katsayısı (a = .915) hesaplanmıştır. Elde edilen sonuçlar; “Öğretim programı”, “kişisel ilgi”, “bilimin belirsizliği”, “eleştirel bakış”, “öğrenci iletişimi” olmak üzere 5 boyuttan ve 21 maddeden oluşan “Yapılandırmacı Müze Öğrenme Ortamları Ölçeği (Y-MÖOÖ)”nin, okul dışı öğrenme ortamları araştırmalarda öğrenci merkezli uyguları değerlendirmek için kullanılabilecek geçerli ve güvenilir bir araç olduğunu göstermektedir.
OKUL ÖNCESİ EĞİTİMDE ÖĞRETMENİN İLETİŞİM BECERİLERİNİN ÖNEMİ: AİLE KATILIMI, İŞ BİRLİĞİ VE ÖĞRETMEN-ÇOCUK İLİŞKİSİ
Authors: ATIŞ AKYOL Nevra , ATA DOĞAN Selda , DURMUŞOĞLU Mine
Published: September 2021

Eğitim öğretim sisteminin en önemli dönemlerinden biri olan okul öncesi eğitim sürecinde çocuk ve ailesi ilk kez örgün eğitim kurumunun bir parçası olur. Bu sürecin verimli olabilmesi için okul aile iş birliği ve çocuğun öğretmeni ile olan iletişimi son derece önemlidir. Bu araştırmanın amacı, ailenin okul ve öğretmen ile olan iletişimi, iş birliği, beklentileri, aile katılımı ve öğretmen-çocuk ilişkisi ile okul öncesi öğretmeninin iletişim becerisi arasındaki ilişkilerin incelenmesidir. Araştırma nicel araştırma yöntemlerinden korelasyonel araştırma deseninde planlanmıştır. Araştırmanın örneklemi, basit seçkisiz örnekleme yöntemi kullanılarak belirlenmiş 112 öğretmenden oluşmaktadır. Araştırmada veri toplama aracı olarak “Demografik Bilgi Formu”, “İletişim Becerileri Ölçeği - Yetişkin Formu”, “Öğretmen Aile İletişim ve İşbirliği Ölçeği” ve “Öğrenci-Öğretmen İlişki Ölçeği” kullanılmıştır. Öğretmen iletişim beceri puanları ile öğretmen aile iletişim, işbirliği alt boyut puanları ve öğretmen çocuk ilişki puanı arasındaki ilişki Pearson korelasyon testi ile analiz edilmiştir. Araştırmanın sonucunda okul öncesi öğretmeninin iletişim becerileri ile öğretmen-çocuk ilişkisi, okul öncesi dönemde ailenin okul ve öğretmen ile olan iletişimi, iş birliği, ailenin okul ve öğretmenden beklentileri ve ailenin eğitim sürecindeki aile katılımı düzeyi arasında pozitif yönde anlamlı bir ilişki bulunmuştur. Bu sonuca göre öğretmenlerin iletişim becerilerinin geliştirilmesi, hem ailelerin sürece katılmasında hem de öğretmen-çocuk ilişkisinin geliştirilmesinde önemli görülmektedir.
ÖĞRETMEN ADAYLARININ ARGÜMANTASYON BECERİLERİNİN ÇEŞİTLİ DEĞİŞKENLERE GÖRE ANALİZİ: BİR UZAKTAN EĞİTİM ÇALIŞMASI
Authors: CİRİT GÜL Ayça , APAYDIN Zeki
Published: September 2021

Öğretmen adaylarının; öğretmenlik mesleğine başladıklarında, öğrencilerini, öğrenmeye açık, kendi düşüncelerini ve karşıt düşünceleri sorgulayan ve araştırma becerisine sahip bireyler olarak yetiştirebilmeleri için; belli bir konuya ilişkin iddialara yönelik argümanları doğru algılamaları ve değerlendirebilmeleri gerekmektedir. Bu çalışmada da, öğretmen adaylarının, kendilerine sunulan iddia ve argümanları nasıl değerlendirdikleri Sampson ve Clark (2006) tarafından geliştirilen ve Kaya vd. (2014) tarafından Türkçeye uyarlanan argümantasyon testi aracılığıyla incelenmiştir. Çalışma, Karadeniz Bölgesi’nde yer alan üniversitelerden birinde öğrenim görmekte olan öğretmen adayları ile yürütülmüştür. Çalışmaya 193 öğretmen adayı katılmıştır. Veriler, 2019-2020 eğitim-öğretim yılında eğitimin uzaktan yürütülmesinden dolayı online bir form aracılığı ile toplanmıştır. Çalışmadan sağlanan verilere göre, öğretmen adaylarının ilgili argümantasyon sürecine yönelik bilgi birikimleri olduğunda oluşturdukları argümanların kalitesi ve argümanları tanımlama, açıklama, analiz etme ve değerlendirme becerilerinin arttığı sonucuna ulaşılmıştır.
THE STRUCTURE ANALYSIS OF BUILDINGS IN TURKEY AND SELECTION OF THE STRUCTURE
Authors: BOSTANCIOĞLU Esra
Published: September 2021

Aim Building structures are assessed with several parameters such as cost, construction time, fire resistance, life cycle, maintenance and repair frequency, and environmental impacts. Building structures are reviewed as masonry, steel framed, wood framed, reinforced concrete framed, composite and prefabricated structures. This study aims to analyze the existing building stock of Turkey and assess the existing buildings in terms of their structural system decisions. Method: Following the comparative assessment of the types of structures based on literature review, assessment criteria for the selection of structural system are determined and a statistical analysis of the existing building stock in Turkey has been made in terms of the use of different structures. A questionnaire was prepared for the architects who decided the structural system in the design phase. Respondents evaluate the structural systems and selection criteria. Statistical analysis is made with the results of the survey. Findings: There is a clear preference for reinforced concrete framed structures in Turkey. A quantitative assessment of the structural systems in the existing buildings in Turkey by 2018 shows that 93.13% of the building stock has reinforced concrete framed. Looking at the individual years in the 2009 to 2018 period, the rate of preference of using reinforced concrete framed structures never went below 89% among all types of structures, but steel framed structure is the most preferred structural system at the end of the survey. Conclusion: It is thought-provoking that although different structures have different comparative advantages, structures other than reinforced concrete framed are preferred so little. The findings will contribute to making the right decision in building structure with the assessment of different structures in different aspects.
AN INVESTIGATION ON INTERACTIVE THEMES APPERTAINING TO DESIGN EDUCATION, AS CONCEPTUAL COMPONENTS OF A SYSTEM
Authors: ÇALGÜNER Alper
Published: September 2021

Design education is a highly interdisciplinary area of study, reserving continual common problematics that have close affiliation with technological change, communicative tools or periodic social tendencies, as well as cognitive approaches. This complex operational network necessitates a heuristic approach, involving systemic and intuitive processes synchronously. Aim: Considering the traditional arduousness of defining, measuring or even predicting the existing or probable quantifiable outputs of an educational model focusing on various design disciplines, a basic framework for a conceptual model basing interactive association is constructed, using extensively adopted words or phrases to clarify possible connections for giving way to foreseeable creative ideational strikes in a sustainable educative process. Method: Stated words and phrases are coded and positioned on a comprehensive base quoted from the literature, followed by a mapping via eight generic titles that are used as a tool set for making a classificative settlement on a specific table, peculiar to the research. Components of the table are planned to be associated for an interactive interpretation through the discussion, in the light of the research aims. Results: Intraindividual methodical operation process of this study has shown the decisive effect of systemic thinking in formulating a theoretical guideline for a futuristic design education approach. Particular outcomes point out the actual dominancy of interactive educative models across innovative activities. Conclusion: Particular findings of the research point out that a systems oriented prudential educational guideline, formulating the utilization of intuitive thinking, would revive future-proof approaches concerning design education. Primarily emphasized conceptual factors that are proposed to focus on design education in the light of inferences of this study, are introduced as systemic reasoning, temporal fluidity of educative concepts, cognitive interaction, sustainable innovation and flexible conceptual platforms.
MODELING THE DYNAMICS OF AN INFECTIOUS DISEASE TAKING INTO ACCOUNT SPATIAL-DIFFUSE PERTURBATIONS, CONCENTRATED INFLUENCES AND ENVIRONMENT CURVATURE
Authors: Baranovsky S. V.
Published: September 2021

While the study of the interaction patterns of the immune system and the viruses detected in the body wide variety of models is used. Well-known infectious disease model by Marchuk which describes the most common mechanisms of immune defense, was obtained under the assumption that the environment of the "organism" is homogeneous and unlimited, in which all the active factors of the process are instantly mixed. The approach proposed by the authors to take into account the influence of spatially distributed diffusion "redistributions" on the nature of the infectious disease provides an opportunity to detect the reducing effect the model level of maximum antigen concentration at the infection epicenter due to their diffusion "erosion" in the disease development. In particular, in cases where the viral particles concentration at the initial time or the intensity of a concentrated source of viruses in any part of the body of infection exceeds a certain critical level of the immunological barrier such an effect of diffusion "redistribution" in a short time reduces supercritical concentrations of viral particles to values, in particular, already below the critical level and their further neutralization may be ensured by the existing level of own antibodies concentration or requires a more economical procedure of injection with a lower donor antibodies concentration. In this article the infectious disease mathematical model is generalized to take into account the curvature of the bounded environment in the conditions of spatial diffusion perturbations, convection and the presence of various concentrated influences. The corresponding singularly perturbed model problem with delay is reduced to a sequence of "solvable" problems without delay. The influence of "curvature" of a limited environment on the development of an infectious disease in the conditions of diffusion perturbations, convection and concentrated influences is illustrated.
Rupture process of an earthquake with kilometric size fault inferred from the modeling of near-source records
Authors: Gariel Jean-Christophe , Archuleta Ralph J. , Bouchon Michel
Published: September 2021

We use the exceptional set of strong ground motion records obtained during one of the largest aftershocks (ML = 5.0) of the 1979 Imperial Valley earthquake to study the time history of rupture on a kilometric size fault. We apply single crack, composite cracks, and dislocation earthquake models to simulate the source and calculate the ground velocity and acceleration at the recording sites. The best fit to the data is obtained for a crack-like source where rupture is initiated at one edge and expands circularly over the fault. The stress drop inferred is 720 bars, and the fractured area has a diameter of about 1 km. The fault is vertical and strikes in the N320°E direction. This simple model explains surprisingly well the amplitudes and waveforms of the ground velocities and accelerations recorded in the near-source region during the event.
Comparison of strong-motion spectra with teleseismic spectra for three magnitude 8 subduction-zone earthquakes
Authors: Houston Heidi , Kanamori Hiroo
Published: September 2021

We studied strong-motion spectra observed for three Mw 7.8 to 8.0 earthquakes (the 1985 Michoacán, Mexico; 1985 Valparaíso, Chile; and 1983 Akita-Oki, Japan earthquakes). We determined the decay of spectral amplitude with distance from the station, considering different measures of distance from a finite fault. We compared strong-motion spectra (Fourier acceleration spectra) observed for these three earthquakes with those estimated from the source spectrum determined from teleseismic P waves. We scaled the teleseismic source spectra to produce reference strong-motion spectra at periods from 1 to 10 sec using a simple physical model of far-field S body waves from a point source recorded at the surface of a homogeneous half-space. For all three earthquakes the reference spectral amplitudes at periods of 1 to 5 sec are about half the observed ones at distances of about 50 km. The difference increases as the distance increases. At distances of 200 to 300 km, the reference spectrum is about 1/10 of the observed one. The difference between the reference and the observed spectrum is attributed to the contribution of phases other than direct S waves and to site response. We applied corrections for the finiteness (spatial extent) of the source using a simple model of rupture propagation on a dipping two-dimensional fault. Including the source finiteness did not improve the estimate substantially at periods from 1 to 20 sec, but it modeled significant changes in the signal duration as a function of azimuth for the 1985 Michoacán earthquake. Our results can be used to establish empirical relations between the observed spectra and the half-space responses, depending on the distance and the site condition. If such empirical relations can be established, source spectra determined from teleseismic records may be used to estimate strong motions.
Limits of sensitivity of inertial seismometers with velocity transducers and electronic amplifiers
Authors: Riedesel Mark A. , Orcutt John A. , Moore Robert D.
Published: September 2021

Portable instruments such as ocean bottom seismographs and the PASSCAL recorders often use rugged, portable geophones. The desire to use such sensors for relatively low-frequency work has raised questions about the limits of their sensitivity. The lower and upper frequency limits of performance of seismic sensors are determined by the sensor's mass, period, and Q, and by the amplifiers used with those sensors. We have tested Mark Products 1 Hz, 2 Hz, and 4.5 Hz velocity transducers against Streckeisen seismometers in order to examine the limits of their performance in measuring ground noise, particularly at low frequencies. Among the velocity transducers, only the 1 Hz Mark Products L-4 sensor provided good resolution of the 6-sec microseism peak. For this sensor, the lower limits of sensitivity was at approximately 0.06 Hz, although this depends on the amplifier used and the noise level at a given site. The amplifiers examined included conventional, low power, and commutating auto-zero operational amplifiers. It was found that the noise levels of the amplifiers intersected the ground noise level at frequencies ranging between 0.06 and 0.2 sec, depending on the amplifier and the exact circuit design. Measurements indicated that by modeling the amplifier noise for a given circuit correctly, the performance of an amplifier can be predicted with a high degree of accuracy, obviating the need for actual circuit construction to determine performance in the field. Given the very steep slope of the ground noise spectrum between 0.05 and 0.1 Hz and the rapid fall off in a seismometer's output below its resonant frequency, it would require a lowering of amplifier noise by more than an order of magnitude to be able to resolve ground noise at frequencies lower than 0.05 Hz using relatively small geophones such as the L-4. To resolve ground noise at lower frequencies, it is necessary to use a seismometer with a displacement transducer to sense the mass position, such as Guralp or Streckeisen sensors.
Initial results from the Intelligent Monitoring System
Authors: Bratt Steven R. , Swanger Henry J. , Stead Richard J. , Ryall Floriana , Bache Thomas C.
Published: September 2021

The Intelligent Monitoring System (IMS) integrates advanced technologies in a knowledge-based distributed system that automates most of the seismic data interpretation process. Results from IMS during its first 8 weeks of operation (1 October through 25 November 1989) are analyzed to evaluate its performance. During this test period, the IMS processed essentially all data recorded by the NORESS and ARCESS high-frequency arrays in Norway. The emphasis was on detection and location of regional events within 2,000 km of these arrays. All events were reviewed and corrected if necessary by a skilled analyst. The final IMS Bulletin for the period includes 1,580 regional events (∼280 events/day). Approximately 55 per cent were smaller than MLg 1, with the largest just over MLg 3.

Comparison of IMS locations in southern Finland and northwestern USSR (800 to 900 km from both arrays) with event locations from the University of Helsinki's local network bulletin are used to assess the detection and location capabilities of the system. Two or more phases (minimum needed to locate) were detected for 96 per cent of the events with magnitude greater than 2.5. The median separation between the IMS and Helsinki locations for all common events was 23.5 km. A consistent bias in arrival-time and azimuth residuals was observed for events in small geographic areas, indicating that refined travel-time models and path corrections could further improve location accuracy.

The knowledge base in this first version of IMS was based on analysis of NORESS data, and many of the errors in interpretation corrected by the analysts can be attributed to differences encountered when this knowledge is used to interpret ARCESS data. Nevertheless, nearly 60 per cent of the events appearing in the final bulletin are automatic solutions approved without change or moved (by analyst corrections) less than 25 km from the automatic locations. The IMS had the most difficulty interpreting the overlapping signals generated by closely spaced explosions commonly detonated at mines in the Kola Peninsula and northern Sweden. Using the knowledge acquisition facilities included in the system, the deficiencies responsible for these and other errors are isolated, leading to development of new knowledge to be incorporated in the next version of the IMS knowledge base.
Azimuth estimation capabilities of the NORESS regional seismic array
Authors: Bame Dorthe A. , Walck Marianne C. , Hiebert-Dodd Kathie L.
Published: September 2021

We have investigated the regional Pn backazimuth estimation capabilities of the NORESS seismic array as a function of element spacing, frequency band, and time window to determine which parameters are optimal for reducing azimuth errors. We used a broadband frequency-wavenumber estimator to calculate backazimuths from the Pn arrival for each of 274 regional events recorded at NORESS for 126 parameter combinations. The large data base provides a wide range of signal-to-noise ratio (SNR) (0 to 70 dB), distance (up to 10.5°), and azimuth characteristics, and includes identified earthquakes and explosions as well as “unknown” sources. Most of the errors in backazimuth are less than 20° when appropriate parameters are used, and mean backazimuth errors are close to zero. The best results are obtained using a 13-element array configuration that has a 1.4 km aperture and a maximum station spacing of about 600 m. With the 13-element configuration and the data filtered to include frequencies between 3 and 10 Hz, the mean errors for the 274 event data set are less than 1.4°, and standard deviations are as small as ± 11.1°. The entire array also produces good results for 3 to 10 Hz, and a 9-element configuration (two inner rings) performs well at high frequencies. The five-element B-ring (600 m aperture) appears to be important in obtaining good backazimuth estimates for regional Pn waves. Of the frequency bands considered in this study, the 3 to 6 Hz, 4 to 8 Hz, and 5 to 10 Hz bands yield the most reliable backazimuth estimates, even better than an “optimal” band that calculates the azimuth in the fixed frequency band that has the largest average SNR. The time-window length has little effect on the backazimuth estimates. Other factors investigated include SNR, source region, and phase type. We found that event backazimuth accuracy degrades if the SNR of a beamed Pn signal is less than 5 dB in the frequency band of interest. Conversely, the backazimuth estimation statistics improve if only events with 5 dB of SNR are included in the event set. These data sets yield near-zero mean errors and smaller standard deviations than the entire data set. For specific source regions, standard deviations are as low as 2° for some parameter combinations, but there can also be large biases in the backazimuth estimates. Events farther than 500 km from NORESS tend to have larger azimuth errors than the closer events, but combinations of small aperture configurations and middle (3 to 10 Hz) frequency bands work well for events over the entire distance range of 40 to 1200 km. The Pn arrival and RONAPP azimuths calculated from the Lg phase have similar accuracy statistics for a 220 event common data base, implying that the two phases work equally well for regional event backazimuth estimation. In fact, averaging of the Lg and Pn estimates provides the most accurate backazimuths relative to PDE reference information.
An on-line analysis system for three-component seismic data: Method and preliminary results
Authors: Kedrov O. K. , Ovtchinnikov V. M.
Published: September 2021

This paper presents the basic method and algorithm of a system for automatic on-line analysis of seismic data at three-component stations and gives preliminary experimental results. Data processing consists of four steps: (1) preliminary detection and estimation of the signal arrival time by using the energy-based γ-detector; (2) refinement of signal parameters (arrival time, amplitude, period, and coda duration); (3) estimation of the azimuth and incident angle of the seismic ray by using polarization analysis; and (4) approximate estimation of event parameters (epicenter coordinate, origin time, and magnitude) from teleseismic P waves for a constrained focal depth.

The software package, which is called “SEISMOSTANSIA,” has been tested in an on-line environment at an experimental seismic station in Eastern Kazakhstan. Testing results show that the system can handle an input flow of up to 100 signals in a 24-hr period. Comparison of the results of automatic detection with data of the station bulletin obtained by visual analysis of analog seismograms shows that: (1) with the present threshold setting, the automatic system detects practically all teleseismic signals seen by the analyst together with typically 10 to 15 signals per day not confirmed by visual analysis; (2) in 70 per cent of the cases, the residual between the arrival time obtained from the automatic and subjective procedures is 0.5 sec or less for SNR > 10 and 1 sec or less for SNR < 10; (3) in 70 per cent of the cases, the residual between the signal period obtained from the automatic and subjective procedures is 0.2 sec or less. Analysis of data indicates that an effective means of identifying false alarms with low SNR can be the level of polarization rectilinearity of P and S waves. By analyzing azimuth estimates for a suite of explosions at the Nevada Test Site, it is shown that a systematic bias forms the main contribution to the residual relative to true azimuth. In the general case, the azimuth residuals are due to the features of the medium both at the epicenter and at the station, and consequently depend on both azimuth and epicentral distance. An analysis of azimuth residuals points to a periodic dependence on azimuth. The value of the period is about 120°. Additional information (azimuth and angle of incidence) reported from three-component stations to data centers is shown to improve significantly the reliability of phase association in the processing of data from a global seismic network.
The GEOSCOPE program: Present status and perspectives
Authors: Romanowicz Barbara , Karczewski Jean François , Cara Michel , Bernard Pascal , Borsenberger Jean , Cantin Jean-Michel , Dole Bernard , Fouassier Danielle , Koenig Jean-Claude , Morand Michel , Pillet Robert , Pyrolley Annick , Rouland Daniel
Published: September 2021

GEOSCOPE is a global three-component digital broadband seismological network deployed by France. It presently counts 22 stations, with a final goal of 25 stations, representing the French contribution to the new generation global seismological network, an international effort coordinated through the Federation of Digital Seismic Networks, and the basic tool for global seismology of the 1990s.
Polarization analysis of high-frequency, three-component seismic data
Authors: Bataille K. , Chiu J. M.
Published: September 2021

We present a method to determine the polarization of body waves from three-component, high-frequency data and examples of its application. The method is based on the principal component approach. One advantage of this approach is that the polarization state can be determined for small time windows compared with the predominant period of the wave. This is particularly useful for identifying converted waves within the crust. The stability of the result is analyzed with synthetic cases by adding simultaneous arrivals from waves and random noise. The method works well with both synthetic and local data in the detection of the polarization of the wave by separating arrivals from different directions. From the local data, some seismic phases related to crustal conversions are observed that require strong lateral variations.
Modeling of wave propagation in northern Los Angeles basin
Authors: Sen Mrinal K.
Published: September 2021

The Los Angeles basin is characterized by deep structural complexity and is the site of numerous earthquakes. We analyze the amplitude and waveform data of earthquakes recorded in the Los Angeles basin in order to identify the structurally controlled path effects. This has been done in order to determine which features of the structure affect the observations and to generate improved models in different parts of the basin increasing our capabilities of predicting seismic hazard. Several structural models of the L.A. basin that are based on regional subsurface studies, exposed sections, scattered oil wells, and other limited geophysical data have recently become available. In this study, we have used seismic modeling techniques together with geologic models to attempt to explain site variations in some important data bases. We have modeled waveforms of (1) the 19 January 1989 Malibu earthquake data recorded in Pasadena, (2) an M = 2.8 earthquake recorded by the USC downhole array in the Baldwin Hills, southern California, and (3) two aftershocks of the Whittier Narrows earthquake recorded at five stations along a profile.

The modeling of the Malibu earthquake results in a layered one-dimensional model representing 6.5 km of layered sediment underlain by a high-velocity basement. Direct arrivals, basin reflected phases, and multiple reverberations are modeled fairly well by this one-dimensional model. The downhole array data in the Baldwin Hills show a significant near-surface amplification that can be modeled by very low-velocity near-surface materials. A series of aftershocks of the Whittier Narrows earthquake recorded at close distances at temporary recording sites shows a wide variation in peak accelerations due both to radiation pattern and propagation effects. The effect of lateral heterogeneity is evident in the travel time, where stations within the basin show later arrival times than those away from the basin for the same epicentral distance. Seismograms recorded at different sites show variation in waveforms due to multi-pathing of rays. We use such triplicated arrivals to constrain the structure of different interfaces. Using these criteria and the synthetic seismograms calculated by ray theory and finite difference methods, we have been able to model the tangential seismograms due to two of these events recorded at five stations along a two-dimensional profile.

All three modeling exercises helped us understand wave propagation in the basin environment. A basin-reflected phase was identified in the seismogram from the Malibu earthquake, which was used to derive an effective depth of the basement. Near-surface amplification of the waves observed in the downhole data could be explained by constructive interference of the multiply reflected waves through the thin near-surface low-velocity layer. Similarly, site-dependent variation of waveform and travel time shown by the seismograms from the aftershocks of the Whittier Narrows, California, earthquake could be accounted for when a laterally varying structure was used.
Origin of precursors to teleseismic S waves
Authors: Vinnik Lev. P. , Romanowicz Barbara A.
Published: September 2021

In the literature, there are descriptions of precursors to teleseismic S waves that are polarized as teleseimic P. They are commonly regarded as phases converted from SV to P underneath the seismographic stations. We present observations of precursors at the broadband digital GEOSCOPE stations in the distance range from 45° to 95° and at periods around 10 sec. These precursors are polarized as the teleseismic P but cannot be interpreted in terms of conversion underneath the station. We propose that they are formed by conversion and scattering from S to P at the free surface and scattering of the resulting P in the lithosphere of the region between the source and the receiver. The apparent velocity of S in the region of scattering is usually around 7 km/sec, which implies a long wavepath of the converted P in the continental crust. Apparently, S-to-P and P-to-P scattering play an important role in forming teleseismic wave fields even in the relatively long-period band around 10 sec. A possibility of observing true S-P converted phases originating in the lithosphere underneath the station is certainly not ruled out. However, our analysis is a warning that scattered waves sometimes can be erroneously taken for converted phases.
The EARSS digital seismograph: System description and field trials
Authors: Gledhill K. R. , Randall M. J. , Chadwick M. P.
Published: September 2021

An earthquake detection and recording system known as EARSS has been developed for permanent seismograph stations and temporary field installations. It records three components of ground motion with a dynamic range of 120 dB. A frequency-domain algorithm detects earthquakes and initiates the recording of data on magnetic tape. Alternatively, EARSS can record data continuously, for preselected periods of time, or recording can be triggered by a time-domain phase picker. Up to 1500 earthquakes (25.5 Mbytes) can be recorded on each magnetic tape cartridge. The field version of EARSS supplies power to the tape drive only when data is being written to tape, thus reducing the normal power consumption of 12 watts (at 12 volts) to 2.5 watts. A field trial using a network of eight EARSS seismographs resulted in 1020 successful station-days of operation from a possible total of 1098 station-days (3 years). Of the 78 lost days of operation, 23 were due to power supply problems external to EARSS, and 52 were caused by a low-temperature failure of the recording system, which has since been corrected. A total of 442 Mbytes of data were recorded, of which about 250 Mbytes were useful data.
Rupture model of the 1989 Loma Prieta earthquake from the inversion of strong-motion and broadband teleseismic data
Authors: Wald David J. , Helmberger Donald V. , Heaton Thomas H.
Published: September 2021

We have used 24 broadband teleseismic and 48 components of local strong-motion velocity records of the 1989 Loma Prieta earthquake in a formal inversion to determine the temporal and spatial distribution of slip. Separate inversions of the teleseismic data (periods of 3 to 30 sec) or strong-motion data (periods of 1 to 5 sec) result in similar models. The data require bilateral rupture with relatively little slip in the region directly updip from the hypocenter. Slip is concentrated in two patches: one centered 6 km northwest of the hypocenter at a depth of 12 km and with a maximum slip of 350 cm, and the other centered about 5 km southeast of the hypocenter at a depth of 16 km and with a maximum slip of 460 cm. The bilateral nature of the rupture results in large amplitude ground motions at sites located along the fault strike, both to the northwest and the southeast. However, the northwestern patch has a larger moment and overall stress drop and is, consequently, the source of the largest ground motion velocities, consistent with the observed recordings. This bilateral rupture also produces relatively modest ground motion amplitudes directly updip from the hypocenter, which is in agreement with the velocity ground motions observed at Corralitos. There is clear evidence of a foreshock (magnitude between 3.5 and 5.0) or a slow rupture nucleation about 2 sec before the main part of the rupture; the origin time implied by strong-motion trigger times is systematically 2 sec later than the time predicted from the high-gain regional network data. The seismic moment obtained from either of the separate data sets or both sets combined is about 3.0 × 1026 dyne-cm and the potency is 0.95 km3.
Ground motion at the San Francisco international airport from the Loma Prieta earthquake sequence, 1989
Authors: McGarr A. , Çelebi M. , Sembera E. , Noce T. , Mueller C.
Published: September 2021

Following the Loma Prieta earthquake, the U.S. Geological Survey installed four portable digital seismic recorders at the San Francisco International Airport (SFO) for one week to study aftershock ground motion at this important Bay area “lifeline.” This study was motivated largely by the need to anticipate strong ground motion from future major earthquakes affecting the Bay area and, to a lesser extent, by the fact that SFO was shut down for 13 hours owing to damage from the Loma Prieta shock. Accordingly, the recording sites were chosen so as to elucidate the effects of varying thicknesses of low-velocity surficial alluvium on the ground motion. Three large aftershocks with magnitudes ranging from 4.2 to 4.5 each produced ground motion that was recorded at all four SFO stations. One of our stations was collocated with a permanent ground motion recorder that indicated a peak horizontal velocity of 29 cm / sec and a peak horizontal acceleration of 0.33 g during the 18 October mainshock. From the aftershock data and one mainshock record, it is possible to extrapolate approximately the mainshock ground motion to other locations at SFO and, more generally, to assess the effects of low-velocity sedimentary cover, including artificial fill material, on the character of the ground motion. The main-shock ground motion recorded at the permanent station was apparently typical for most of SFO where the near-surface alluvium resulted in peak horizontal ground velocity, in the frequency band 0.1 to 3 Hz, amplified by a factor of about 2.5 relative to that recorded at bedrock sites. Observations, in the epicentral distance range 59 to 95 km, including SFO, of the moho-reflected phases PmP and SmS from the aftershocks support the hypothesis, presented elsewhere, that the phase SmS accounted for much of the peak ground motion throughout most of the San Francisco Bay area.
Evaluation of the failure of the Cypress Viaduct in the Loma Prieta earthquake
Authors: Miranda Eduardo , Bertero Vitelmo V.
Published: September 2021

This article describes analytical studies performed to explain the collapse of the Cypress Street Viaduct. The modes of failure of four types of bents are described. A strength analysis is presented, which gives estimates of the forces that were necessary to produce the failure of these bents. These estimates are computed based on the observed failure mechanism of each type of bent, on measured mechanical characteristics of the materials, and on simplified structural models. The overstrength of these bents, above the level of forces for which they were designed, is evaluated. Levels of acceleration required to produce the failure are given. From comparison of these levels of accelerations with those resulting from the elastic as well as the inelastic response spectra corresponding to ground motions recorded near the Viaduct, it is concluded that the demanded shear strength was considerably higher than the supplied strength and that bent type B8 was the weakest one and where the failure was probably initiated.
Inversion of complex body waves—III
Authors: Kikuchi Masayuki , Kanamori Hiroo
Published: September 2021

We have developed a method that inverts seismic body waves to determine the mechanism and rupture pattern of earthquakes. The rupture pattern is represented as a sequence of subevents distributed on the fault plane. This method is an extension of our earlier method in which the subevent mechanisms were fixed. In the new method, the subevent mechanisms are determined from the data and are allowed to vary during the sequence. When subevent mechanisms are allowed to vary, however, the inversion often becomes unstable because of the complex trade-offs between the mechanism, the timing, and the location of the subevents. Many different subevent sequences can explain the same data equally well, and it is important to determine the range of allowable solutions. Some constraints must be imposed on the solution to stabilize the inversion. We have developed a procedure to explore the range of allowable solutions and appropriate constraints. In this procedure, a network of grid points is constructed on the τ - I plane, where τ and I are, respectively, the onset time and the distance from the epicenter of a subevent; the best-fit subevent is determined at all grid points. Then the correlation is computed between the synthetic waveform for each subevent and the observed waveform. The correlation as a function of τ and I and the best-fit mechanisms computed at each τ - I grid point depict the character of allowable solutions and facilitate a decision on the appropriate constraints to be imposed on the solution. The method is illustrated using the data for the 1976 Guatemala earthquake.
A three-component borehole seismometer for earthquake seismology
Authors: Liu Hsi-Ping , Warrick Richard E. , Westerlund Robert E. , Fletcher Jon B.
Published: September 2021

We have developed a three-component borehole seismometer, using 2-Hz electromagnetic moving-coil geophones as sensing elements. The main achievement of our new borehole package is a compact internal device for leveling horizontal geophones. Horizontal moving-coil geophones with a period longer than 0.5 sec need to be leveled to better than 1.5° to avoid nonlinear response and asymmetric clipping. In boreholes, where the axis of the package may well deviate from the vertical by more than 1.5°, a special device is required for leveling the horizontal geophones. A gimbal stage was adapted from the design of ocean-bottom seismometers for leveling the two orthogonally oriented horizontal geophones: the geophones can be leveled to better than 0.1° from an initial tilt of 10.5°. The external package is 14 cm in diameter and approximately 40 cm long. The gimbal stage uses free-flex flexural pivots and, during the leveling operation, suspends a brass pendulum that houses the horizontal sensors. In comparison with borehole seismometers that use electronic-feedback principles, the disadvantages of our system are a lack of response at long periods and, because of coil contacting stops, its inability to record strong motions. Nonetheless, it has an inherently low noise level, consumes no power, is simple to build, and is inexpensive; it is therefore suitable for rapid deployment for aftershock studies and for low-noise operation at remote sites. Such seismometers, using Mark Products L-22D 2-Hz geophones, have been installed at several sites in California: at the bottom of adjacent boreholes ∼ 150 and ∼ 300 m deep, in granite at station KNW near Keenwild and at Piñon Flat of the Anza digital seismic array, and at the bottom of an 88-m-deep borehole in hydrothermally altered serpentine in the Marina District of San Francisco. The effects of cable impedance on the geophone output have been analyzed and found to be negligible for a cable length of 335 m consisting of four pairs of shielded #20 gauge wires. Azimuthal orientation of horizontal geophones can be determined using first P-arrival particle motion generated by regional earthquakes. Earthquake data recorded by these borehole seismometers have been employed by several investigators for studies on the effects of near-surface weathered rocks on the corner frequencies of earthquake spectra near Anza, California, on the seismic-shear-wave-polarization characteristics of seismograms recorded in the southern California batholith at 300 m depth, and on site-resonance amplification caused by sedimentary deposits overlying bedrock in the Marina District of San Francisco.
MicroHikari3D: Transformando una impresora 3D en un microscopio robotizado moderno
Authors: Toledano Pablo T. , Bueno Gloria , Vállez Noelia , Déniz Óscar , Salido Jesús
Published: September 2021

Los microscopios son una herramienta imprescindible para diferentes aplicaciones en biología y medicina, entre otros. La automatización de estos microscopios y la integración de herramientas de análisis automático de imagen es un gran avance en microscopía, pero la mayoría de los sistemas disponibles en el mercado con estas prestaciones tienen un precio elevado. Por otro lado, en los últimos años ha habido un auge importante del desarrollo y venta de impresoras 3D a un precio muy asequible. Por ello, en este trabajo se busca ofrecer un kit modular que permita convertir una impresora 3D en un microscopio motorizado completamente funcional y automatizado. Para conseguir este objetivo, se ha seleccionado una impresora 3D, de la que se ha reaprovechado el eje de movimiento cartesiano, y se le ha acoplado un sistema óptico basado en Raspberry Pi HQ Camera, una iluminación superior e inferior y además de una base para portaobjetos nueva. Así como herramientas de procesado y métodos de clasificación automática de la imagen. Con esto se conseguirá un sistema de microscopía modular y de bajo coste, capaz de capturar muestras microscópicas de organismos y tejidos en portas 2D y en placas Petri 3D.
Optimización del rendimiento en sistemas de control mediante entropía
Authors: Ruiz-Alba Antonio , Sharman Ken , Sáez Sergio
Published: September 2021

Calculamos, analizamos y medimos la entropía relativa en sistemas de control. Los datos obtenidos se pueden utilizar para detectar errores en su funcionamiento o para ajustar los recursos de cálculo de los componentes, mejorando su rendimiento. Evaluamos la ventaja del método a través de un experimento de simulación.
DRNN Robust DTC for Induction Motor Drive Systems Using FSTPI
Authors: Dube Lucky , Bayoumi Ehab H.E.
Published: September 2021

In this paper, a self-tuning PI speed controller based on diagonal recurrent neural network is (DRNN) investigated and simulated to increase the robustness of the direct torque control (DTC) scheme for three-phase low-power IM drive system using a Four Switch Three-Phase Inverter (FSTPI). The drive is subjected to different system inputs and disturbances, step changes in speed under different load conditions, abrupt loading at high speed and speed reversal. Furthermore, the robustness of the controller is evaluated by varying motor parameter, stator resistance and moment of inertia. A comparison of classical and self-tuning PI speed controllers was presented to determine the effectiveness of the proposed controller. It is concluded based on simulation results using Matlab/Simulink. that the self-tuning PI speed controller provides the best performance by reacting rapidly and adaptively.