scholarly journals SEISMIC REFLECTION OF COMPLEX GEODYNAMIC PROCESSES IN THE OROGENES OF THE GREATER AND LESSER CAUCASUS

2018 ◽  
Author(s):  
Б.В. Саакян
Keyword(s):  
Earthquake Prediction ◽  
Seismic Reflection ◽  
Time Development ◽  
Short Term ◽  
Time Intervals ◽  
Greater Caucasus ◽  
Seismological Data ◽  
Geodynamic Processes ◽  
Lesser Caucasus

В работе рассматриваются отражения пространственно-временных развитий сейсмичностей за период (1900–2000гг.) по крупному сейсмическому линеаменту Эрзрум-Боржоми-Казбек (ЭБК) в геодинамике орогенах Большого и Малого Кавказа, а также установление его связи с выявленными геодезическими и морфоструктурными данными современных движений этих орогенов. Показано, что выявленные по сейсмологическим данным периоды сейсмических активизаций и заключенные между ними временные интервалы относительных сейсмических затиший, адекватно отображают выявленные по геодезическим данным кратковременные эпохи опускания и поднятия орогенов Малого и Большого Кавказа. Полученные результаты позволяют использовать сейсмологические данные для реконструкции современных движений, а также в исследованиях, направленных на решение проблемы долгосрочного прогноза землетрясения. Within the following paper reflections of the space-time development of seismisity for the period (1900–2000) on the large Erzurum-Borzhomi-Kazbeki (EBK) seismic lineament in the geodynamics of the orogenes of the Greater and Lesser Caucasus are considered, as well as its relation to the identified geodetic and morphostructural data of modern movements of these orogens. Seismic activation periods obtained through seismological data and the time intervals of relative seismic calm concluded between them adequately reflect the short-term epochs of lowering and raising the orogens of the Lesser and Greater Caucasus, identified by geodetic data. The obtained results allow using seismological data for the reconstruction of modern movements, as well as in studies aimed at solving the problem of long-term earthquake prediction

scholarly journals Evaluation of long-term sagittal lip changes using Burstone line: Pilot Study

2021 ◽  
Vol 7 (2) ◽  
pp. 32-37
Author(s):  
Rachel Sathekge ◽  
Colin Lesar
Keyword(s):  
Soft Tissue ◽  
Upper Lip ◽  
Short Term ◽  
Time Intervals ◽  
Lower Lip ◽  
Linear Distance ◽  
Long Term Follow Up ◽  
The Mean

Objective Lip position has become one of the most important soft tissue analyses as it influences the occlusion, tooth stability and facial aesthetic. Hence, the objective of this study was to compare the short-term and long-term sagittal lip positions/changes using the Burstone line (B-line).   Methods The sample consisted of 18 Caucasoid females only (14 extractions, 4 non-extractions) who were successfully treated with edgewise appliances. All the patients were evaluated before treatment (T1),at the end of active treatment (T2), and at a long-term follow-up observation (T3). The mean age at commencement was 13.2 years with the range of 10.5-19 years. The linear distance between the tip of the lips and the B-line were measured.   Results T1-T2 time intervals showed the upper lip underwent a mean change of 1.272 mm relative to the B-line (-32.8%) which was statistically significant. The lower lip showed a mean change of 1.549 mm (-22.2%), but these changes were not statistically significant. Lip protrusion relative to the B-line continued to reduce during the long term follow up period. The upper lip showed slight changes (-9.2%), whereas the lower lip demonstrated greater change (-53.8%).   Conclusion Using B-line, the sagittal soft tissue lip positions were more retrusive on the long-term follow-up records for both extraction and non-extraction cases, their values were not very different from the normal values of the untreated cases. Although the differences were not statistically significant,  upper lips were retrusive post treatment from T1-T2, while were statistically significant the lower lips were retrusive from T1-T2.

scholarly journals Aerosol quantification with the Aerodyne Aerosol Mass Spectrometer: detection limits and ionizer background effects

2009 ◽  
Vol 2 (1) ◽  
pp. 33-46 ◽  
Author(s):  
F. Drewnick ◽  
S. S. Hings ◽  
M. R. Alfarra ◽  
A. S. H. Prevot ◽  
S. Borrmann
Keyword(s):  
Mass Spectrometer ◽  
Detection Limits ◽  
Short Term ◽  
Time Intervals ◽  
Aerosol Mass Spectrometer ◽  
Aerosol Mass ◽  
Background Measurement ◽  
Averaging Time ◽  
Minimum Detection Limits

Abstract. Systematic laboratory experiments were performed to investigate quantification of various species with two versions of the Aerodyne Aerosol Mass Spectrometer, a Quadrupole Aerosol Mass Spectrometer (Q-AMS) and a compact Time-of-Flight Aerosol Mass Spectrometer (c-ToF-AMS). Here we present a new method to continuously determine the detection limits of the AMS analyzers during regular measurements, yielding detection limit (DL) information under various measurement conditions. Minimum detection limits range from 0.03 μg m−3 (nitrate, sulfate, and chloride) up to 0.5 μg m−3 (organics) for the Q-AMS. Those of the c-ToF-AMS are found between 0.003 μg m−3 (nitrate, sulfate) and 0.03 μg m−3 (ammonium, organics). The DL values found for the c-ToF-AMS were ~10 times lower than those of the Q-AMS, mainly due to differences in ion duty cycle. Effects causing an increase of the detection limits include long-term instrument contamination, measurement of high aerosol mass concentrations and short-term instrument history. The self-cleaning processes which reduce the instrument background after measurement of large aerosol concentrations as well as the influences of increased instrument background on mass concentration measurements are discussed. Finally, improvement of detection limits by extension of averaging time intervals, selected or reduced ion monitoring, and variation of particle-to-background measurement ratio are investigated.

scholarly journals High-Fidelity Perceptual Long-Term Memory Revisited—and Confirmed

2003 ◽  
Vol 14 (1) ◽  
pp. 74-76 ◽  
Author(s):  
Svein Magnussen ◽  
Mark W. Greenlee ◽  
Per Matti Aslaksen ◽  
Ole Øystein Kildebo
Keyword(s):  
Long Term Memory ◽  
High Fidelity ◽  
Short Term ◽  
Time Intervals ◽  
Term Memory ◽  
Visual Attributes ◽  
The Subject ◽  
Criterion Setting ◽  
Method Of Constant Stimuli

Experiments on short-term perceptual memory for elemental visual attributes, such as contrast, motion, orientation, and spatial frequency, have relied on a delayed discrimination technique in which the subject compares two stimuli presented at different points in time and memory is indexed by discrimination thresholds measured for the different time intervals between reference and test. In a variant of this procedure, used in experiments on long-term memory, the presentation of a single reference is followed by a memory test that combines two-alternative forced-choice decisions with the method of constant stimuli. With this procedure, it is impossible to distinguish the effects of criterion-setting processes and memory on performance, but this confound can be eliminated by testing many subjects and having each subject make a single decision. The resulting “group thresholds” are stable across time intervals of 24 hr, confirming previous findings of high-fidelity storage in the long-term memory range.

scholarly journals Environmental influences on neuroticism in adulthood: A systematic review

2018 ◽  
Author(s):  
Bertus F. Jeronimus ◽  
Harriette Riese ◽  
Johan Ormel
Keyword(s):  
Longitudinal Studies ◽  
Mixed Model ◽  
Environmental Influences ◽  
Individual Change ◽  
Short Term ◽  
Time Intervals ◽  
Genetic Studies ◽  
Life Trajectories ◽  
Off Time

Behavioral-genetic studies show substantial non-genetic influences on variance of neuroticism within a population. Longitudinal studies show a small but steady drop in test-retest correlations with increasing time intervals. This suggest environmental effects on neuroticism, but a systematic overview of which environmental determinants account for change in neuroticism is lacking. We review (specific or unique) environmental influences that modify the neuroticism setpoint in adulthood and therewith individual life trajectories. Results are interpreted in light of the so-called ‘mixed model’ in which within-person changes in neuroticism are subdivided over short term perturbations around the setpoint of neuroticism versus more persistent changes in the setpoint itself. To account for genetic confounding and shared environmental influences studies of monozygotic (MZ) twin pairs discordant for neuroticism and longitudinal studies that report on environmental factors that predict within-individual change in neuroticism are reviewed. Our results indicate that the neuroticism setpoint is consistently touched by experiences that affect central aspects of one’s identity and status, mainly role transitions as partner (marriage/divorce) and employee (job loss/promotion). Especially interpersonal stress, conflict, and major events that were unpredictable, uncontrollable, unexpected, undesirable, and ‘off time’ from a life history perspective were followed by changes in neuroticism that persisted more than six months, which suggest setpoint change. Most change after severe SLEs persisted over a decade. Long-term and detailed studies are required to elucidate the details of the ‘mixed model’ of change in neuroticism. An understanding of the specifics of the events that lead to persistent changes in neuroticism may enable us to craft prevention strategies to tackle the vulnerability for mental disorders inherent in high neuroticism, rather than to wait for their manifestation.

scholarly journals On fluctuating momentum-exchange in idealised models of air-sea interaction

2019 ◽  
Author(s):  
Achim Wirth
Keyword(s):  
Momentum Exchange ◽  
Short Term ◽  
Time Intervals ◽  
Random Forcing ◽  
Fluctuation Dissipation ◽  
Fluctuation Dissipation Theorem ◽  
Varying Length ◽  
Atmospheric Motion ◽  
Noise Forcing

Abstract. The dynamics of three local models, for momentum transfer at the air-sea interface, is compared. The models differ by whether or not the ocean velocity is included in the shear calculation applied to the ocean and the atmosphere. All three cases are employed in climate or ocean simulations. Analytic calculations for the models with deterministic and random forcing (white and coloured) are presented. The short term behaviour is similar in all models, which only small quantitative differences, while the long-term behaviour differs qualitatively between the models. The fluctuation-dissipation-relation, which connects the fast atmospheric motion to the slow oceanic dynamics, is established for all models with random forcing. The fluctuation-dissipation-theorem, which compares the response to an external forcing to internal fluctuations is established for a white-noise forcing and a coloured forcing when the phase space is augmented by the forcing variable. Using results from numerical integrations of stochastic differential equations it is shown that the fluctuation-theorem, which compares the probability of positive to negative fluxes of the same magnitude, averaged over time-intervals of varying length, holds for the energy gained by the ocean from the atmosphere.

scholarly journals Time-dependent fitness effects can drive bet-hedging populations extinct

2016 ◽  
Author(s):  
Eric Libby ◽  
William Ratcliff
Keyword(s):  
Resource Competition ◽  
Bet Hedging ◽  
Short Term ◽  
Time Intervals ◽  
Hedging Strategies ◽  
Diversification Strategies ◽  
Environmental Fluctuations ◽  
Long Time ◽  
Temporally Correlated

AbstractTo survive unpredictable environmental change, many organisms adopt bet-hedging strategies that trade short-term population growth for long-term fitness benefits. Because the benefits of bet-hedging may manifest over long time intervals, bet-hedging strategies may be out-competed by strategies maximizing short-term fitness. Here, we investigate the interplay between two drivers of selection, environmental fluctuations and competition for limited resources, on different bet-hedging strategies. We consider an environment with frequent disasters that switch between which phenotypes they affect in a temporally-correlated fashion. We determine how organisms that stochastically switch between phenotypes at different rates fare in both competition and survival. When disasters are correlated in time, the best strategy for competition is among the worst for survival. Since the time scales over which the two agents of selection act are significantly different, environmental fluctuations and resource competition act in opposition and lead populations to evolve diversification strategies that ultimately drive them extinct.

scholarly journals What to Do Next: Modeling User Behaviors by Time-LSTM

2017 ◽  
Author(s):  
Yu Zhu ◽  
Hao Li ◽  
Yikang Liao ◽  
Beidou Wang ◽  
Ziyu Guan ◽  
...  
Keyword(s):  
Neural Network ◽  
Recurrent Neural Network ◽  
Language Modeling ◽  
Sequential Data ◽  
Sequential Order ◽  
Short Term ◽  
Time Intervals ◽  
User Behaviors ◽  
Real World Datasets

Recently, Recurrent Neural Network (RNN) solutions for recommender systems (RS) are becoming increasingly popular. The insight is that, there exist some intrinsic patterns in the sequence of users' actions, and RNN has been proved to perform excellently when modeling sequential data. In traditional tasks such as language modeling, RNN solutions usually only consider the sequential order of objects without the notion of interval. However, in RS, time intervals between users' actions are of significant importance in capturing the relations of users' actions and the traditional RNN architectures are not good at modeling them. In this paper, we propose a new LSTM variant, i.e. Time-LSTM, to model users' sequential actions. Time-LSTM equips LSTM with time gates to model time intervals. These time gates are specifically designed, so that compared to the traditional RNN solutions, Time-LSTM better captures both of users' short-term and long-term interests, so as to improve the recommendation performance. Experimental results on two real-world datasets show the superiority of the recommendation method using Time-LSTM over the traditional methods.

Statistical analysis of microearthquake activity near San Andreas geophysical observatory, Hollister, California

1975 ◽  
Vol 65 (4) ◽  
pp. 809-827 ◽  
Author(s):  
Agustin Udias ◽  
John Rice
Keyword(s):  
High Frequency ◽  
Hazard Function ◽  
High Gain ◽  
Short Term ◽  
Time Intervals ◽  
San Andreas ◽  
Intensity Functions ◽  
High Degree ◽  
Exponential Probability

Abstract Microearthquake activity during the 4-year interval 1968 to 1971 in a region of 25 km radius, centered on the San Andreas fault near Hollister, has been monitored by means of high-gain high-frequency seismographs which allow detection of events as small as magnitude zero within the region. The distribution of the 4764 microearthquakes shows a high degree of clustering. The series of time intervals between consecutive shocks can be described approximately by a gamma distribution whose shape parameters for different samples change from 0.3 to 0.8. The exponential probability plots of the {Δti} series for 265 larger regional earthquakes over 10 years result in a constant value of the hazard function except for small values of time where the hazard is higher. The variance-time and intensity functions show a varying degree of interdependence between events for each year and a long-term dependence up to 80 days for the period 1968-1971. The time scale of clustering has been estimated. Inferences based on short-term microearthquake studies may be grossly misleading.

scholarly journals On fluctuating momentum exchange in idealised models of air–sea interaction

2019 ◽  
Vol 26 (4) ◽  
pp. 457-477
Author(s):  
Achim Wirth
Keyword(s):  
Momentum Exchange ◽  
Short Term ◽  
Time Intervals ◽  
Random Forcing ◽  
Fluctuation Dissipation ◽  
Fluctuation Dissipation Theorem ◽  
Numerical Integrations ◽  
Atmospheric Motion ◽  
Noise Forcing

Abstract. The dynamics of three local models, for momentum transfer at the air–sea interface, is compared. The models differ by whether or not the ocean velocity is included in the shear calculation applied to the ocean and the atmosphere. All three cases are employed in climate or ocean simulations. Analytic calculations for the models with deterministic and random forcing (white and coloured) are presented. The short-term behaviour is similar in all models, with only small quantitative differences, while the long-term behaviour differs qualitatively between the models. The fluctuation–dissipation relation, which connects the fast atmospheric motion to the slow oceanic dynamics, is established for all models with random forcing. The fluctuation–dissipation theorem, which compares the response to an external forcing to internal fluctuations, is established for a white-noise forcing and a coloured forcing when the phase space is augmented by the forcing variable. Using results from numerical integrations of stochastic differential equations, we show that the fluctuation theorem, which compares the probability of positive to negative fluxes of the same magnitude, averaged over time intervals of varying lengths, holds for the energy gained by the ocean from the atmosphere.

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