interval estimate
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2021 ◽  
Author(s):  
◽  
Philippa Morris

<p>The Mw 7.8 Kaikōura earthquake of November 14th 2016 provided unprecedented opportunities to understand how the ground deforms during large magnitude strike-slip earthquakes. The re-excavation and extension of both halves of a displaced paleoseismic trench following this earthquake provided an opportunity to test, refine, and extend back in time the known late Holocene chronology of surface rupturing earthquakes on the Kekerengu Fault. As part of this thesis, 28 organic-bearing samples were collected from a suite of new paleoseismic trenches. Six of these samples were added to the preferred age model from Little et al. (2018); this updated age model is now based on 16 total samples. Including the 2016 earthquake, six surface rupturing earthquakes since ~2000 cal. B.P. are now identified and dated on the Kekerengu Fault. Based on the latest five events (E0 to E4), this analysis yields an updated mean recurrence interval estimate for the Kekerengu Fault of 375 ± 32 yrs (1σ) since ~1650 cal. B.P. The older, sixth event (E5) is not included in the preferred model, as it may not have directly preceded E4; however, if this additional event is incorporated into an alternative age model that embraces all six identified events, the mean recurrence interval estimate (considered a maximum) calculated is 433 ± 22 yrs (1σ) since ~2000 cal. B.P.   Comparison of structures on an identical trench wall logged both before and after the 2016 earthquake, and analysis of pre- and post-earthquake high resolution imagery and Digital Surface Models (DSMs), has allowed the quantification of where and how ~9 m of dextral-oblique slip was accommodated at this site during the earthquake. In addition to this, I analyse the coseismic structure of the adjoining segment of the 2016 ground rupture using detailed post-earthquake aerial orthophotography, to further investigate how geological surface structures (bulged-up moletrack structures) accommodated slip in the rupture zone. These combined analyses allowed me to identify two primary deformation mechanisms that accommodated the large coseismic slip of this earthquake, and the incremental effect of that slip on the structural geology of the rupture zone. These processes include: a) discrete slip along strike-slip faults that bound a narrow, highly deformed inner rupture zone; and b), distributed deformation within this inner rupture zone. The latter includes coseismic clockwise rotation of cohesive rafts of turf, soil and near-surface clay-rich sediment. During this process, these “turf rafts” detach from the underlying soil at a mean depth of ~0.7 m, shorten by ~2.5 m (in addition to shortening introduced by any local contractional heave), bulge upwards by < 1 m, and rotate clockwise by ~19° - while also separating from one another along fissures bounded by former (now rotated) synthetic Riedel faults. This rotational deformation accommodated ~3 m of dextral strike-slip (of a total of ~9 m), after which this rotation apparently ceased, regardless of the total slip or the local kinematics (degree of transpression) at any site. The remaining slip was transferred onto later forming, throughgoing faults as discrete displacement. Analysis of the morphology and amplitude of these moletracks suggests that an increase in the degree of transpression (value of contractional heave) at a site increases the magnitude of shortening and the finite longitudinal strain absorbed by the rotated turf rafts, but does not necessarily contribute to an increase in height (generally 0.33-0.53 m on all parts of the fault). Rather, the comparison of these moletracks with those described by other authors suggests that a more controlling factor on their height is the clay content and cohesion of material deformed into the moletracks.  Finally, comparison of the before and after cross-sections of the displaced paleoseismic trench has provided, for the first time, insight into how large magnitude strike-slip ruptures are expressed in the fault-orthogonal view typical of paleoseismic trenches. Although this rupture involved ~9 m of dextral strike-slip, the cross-sectional view of the re-excavated trenches was dominated by the much lesser component of fault-perpendicular contractional heave (~1.3 m) that occurred in 2016, which did not occur in previous paleoearthquakes at the same site (these were, by contrast, transtensional). This heave was expressed as up to ~2 m of fault-transverse shortening in the inner rupture zone of the trenches, while the ~9 m of strike-slip only created cm-scale offsets across faults. Previous earthquakes at the site were expressed as cm-dm scale, mostly normal dip-separations of sub-horizontal stratigraphic units across faults, suggesting that a change in local kinematics (of ~8°) must have occurred in 2016. Such a small kinematic change may drastically impact the overall ground expression of strike-slip earthquakes - producing also complicated structures including overprinting fault strands in the rupture zone (to a few metres depth). This information poses challenges for structural geologists and paleoseismologists when interpreting (the significance of) structures in future trench walls.</p>


2021 ◽  
Author(s):  
◽  
Philippa Morris

<p>The Mw 7.8 Kaikōura earthquake of November 14th 2016 provided unprecedented opportunities to understand how the ground deforms during large magnitude strike-slip earthquakes. The re-excavation and extension of both halves of a displaced paleoseismic trench following this earthquake provided an opportunity to test, refine, and extend back in time the known late Holocene chronology of surface rupturing earthquakes on the Kekerengu Fault. As part of this thesis, 28 organic-bearing samples were collected from a suite of new paleoseismic trenches. Six of these samples were added to the preferred age model from Little et al. (2018); this updated age model is now based on 16 total samples. Including the 2016 earthquake, six surface rupturing earthquakes since ~2000 cal. B.P. are now identified and dated on the Kekerengu Fault. Based on the latest five events (E0 to E4), this analysis yields an updated mean recurrence interval estimate for the Kekerengu Fault of 375 ± 32 yrs (1σ) since ~1650 cal. B.P. The older, sixth event (E5) is not included in the preferred model, as it may not have directly preceded E4; however, if this additional event is incorporated into an alternative age model that embraces all six identified events, the mean recurrence interval estimate (considered a maximum) calculated is 433 ± 22 yrs (1σ) since ~2000 cal. B.P.   Comparison of structures on an identical trench wall logged both before and after the 2016 earthquake, and analysis of pre- and post-earthquake high resolution imagery and Digital Surface Models (DSMs), has allowed the quantification of where and how ~9 m of dextral-oblique slip was accommodated at this site during the earthquake. In addition to this, I analyse the coseismic structure of the adjoining segment of the 2016 ground rupture using detailed post-earthquake aerial orthophotography, to further investigate how geological surface structures (bulged-up moletrack structures) accommodated slip in the rupture zone. These combined analyses allowed me to identify two primary deformation mechanisms that accommodated the large coseismic slip of this earthquake, and the incremental effect of that slip on the structural geology of the rupture zone. These processes include: a) discrete slip along strike-slip faults that bound a narrow, highly deformed inner rupture zone; and b), distributed deformation within this inner rupture zone. The latter includes coseismic clockwise rotation of cohesive rafts of turf, soil and near-surface clay-rich sediment. During this process, these “turf rafts” detach from the underlying soil at a mean depth of ~0.7 m, shorten by ~2.5 m (in addition to shortening introduced by any local contractional heave), bulge upwards by < 1 m, and rotate clockwise by ~19° - while also separating from one another along fissures bounded by former (now rotated) synthetic Riedel faults. This rotational deformation accommodated ~3 m of dextral strike-slip (of a total of ~9 m), after which this rotation apparently ceased, regardless of the total slip or the local kinematics (degree of transpression) at any site. The remaining slip was transferred onto later forming, throughgoing faults as discrete displacement. Analysis of the morphology and amplitude of these moletracks suggests that an increase in the degree of transpression (value of contractional heave) at a site increases the magnitude of shortening and the finite longitudinal strain absorbed by the rotated turf rafts, but does not necessarily contribute to an increase in height (generally 0.33-0.53 m on all parts of the fault). Rather, the comparison of these moletracks with those described by other authors suggests that a more controlling factor on their height is the clay content and cohesion of material deformed into the moletracks.  Finally, comparison of the before and after cross-sections of the displaced paleoseismic trench has provided, for the first time, insight into how large magnitude strike-slip ruptures are expressed in the fault-orthogonal view typical of paleoseismic trenches. Although this rupture involved ~9 m of dextral strike-slip, the cross-sectional view of the re-excavated trenches was dominated by the much lesser component of fault-perpendicular contractional heave (~1.3 m) that occurred in 2016, which did not occur in previous paleoearthquakes at the same site (these were, by contrast, transtensional). This heave was expressed as up to ~2 m of fault-transverse shortening in the inner rupture zone of the trenches, while the ~9 m of strike-slip only created cm-scale offsets across faults. Previous earthquakes at the site were expressed as cm-dm scale, mostly normal dip-separations of sub-horizontal stratigraphic units across faults, suggesting that a change in local kinematics (of ~8°) must have occurred in 2016. Such a small kinematic change may drastically impact the overall ground expression of strike-slip earthquakes - producing also complicated structures including overprinting fault strands in the rupture zone (to a few metres depth). This information poses challenges for structural geologists and paleoseismologists when interpreting (the significance of) structures in future trench walls.</p>


2021 ◽  
Vol 26 (6) ◽  
pp. 491-507
Author(s):  
А.В. Бондарев ◽  
◽  
В.Н. Ефанов ◽  

Multi-input logic gates based on two-level logic cells MOBILE have short (picosecond) switching times and higher functionality due to the ability to implement logic functions with fewer gates. This creates good prospects for the development of ultra-high-speed FPGAs with a high degree of integration, which are required for organizing high-performance computing. However, the extremely high sensitivity of resonant tunneling elements to changes in the energies of quantum states requires an assessment of the stability of such structures to external influences in real operation. In this work, the problem of assessing the stability of nanoelectronic structures that include resonant tunneling elements is considered. The method for studying the robustness of logic cells MOBILE based on a resonant tunneling diode and an НВТ transistor was proposed, making it possible to find an external interval estimate of the output voltage of the device under study for given interval models of the initial components. The technique is based on the use of systems of topological and parametric equations written in finite increments. It was shown that the proposed decomposition principle for the initial interval model ensures the algorithmic solvability of the problem posed. A computational algorithm for calculating processes in a two-level logical cell MOBILE has been developed. The algorithm provides for step-by-step integration of interval differential equations and solution of interval nonlinear algebraic equations at each step of integration using Kaucher interval arithmetic. The obtained results of the study of processes in a two-level logic cell MOBILE create prerequisites for expanding the field of application of resonant tunneling devices in high-speed monolithic integrated circuits.


Sports ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 155
Author(s):  
James Steele ◽  
Daniel Plotkin ◽  
Derrick Van Every ◽  
Avery Rosa ◽  
Hugo Zambrano ◽  
...  

Purpose: To conduct a systematic review and multilevel meta-analysis of the current literature as to the effects of interval training (IT) vs moderate intensity continuous training (MICT) on measures of body composition, both on a whole-body and regional level. Methods: We searched English-language papers on PubMed/MEDLINE, Scopus, CINAHL, and sportrxiv for the following inclusion criteria: (a) randomized controlled trials that directly compared IT vs MICT body composition using a validated measure in healthy children and adults; (b) training was carried out a minimum of once per week for at least four weeks; (c) published in a peer-reviewed English language journal or on a pre-print server. Results: The main model for fat mass effects revealed a trivial standardized point estimate with high precision for the interval estimate, with moderate heterogeneity (−0.016 (95%CI −0.07 to 0.04); I2 = 36%). The main model for fat-free mass (FFM) effects revealed a trivial standardized point estimate with high precision for the interval estimate, with negligible heterogeneity (−0.0004 (95%CI −0.05 to 0.05); I2 = 16%). The GRADE summary of findings suggested high certainty for both main model effects. Conclusions: Our findings provide compelling evidence that the pattern of intensity of effort and volume during endurance exercise (i.e., IT vs MICT) has minimal influence on longitudinal changes in fat mass and FFM, which are likely to minimal anyway. Trial registration number: This study was preregistered on the Open Science Framework.


2021 ◽  
Author(s):  
Chen Chen ◽  
Spencer R. Haupert ◽  
Lauren Zimmermann ◽  
Xu Shi ◽  
Lars G. Fritsche ◽  
...  

Importance As SARS-CoV-2 pervades worldwide, considerable focus has been placed on the longer lasting health effects of the virus on the human host and on the anticipated healthcare needs. Objective The primary aim of this study is to examine the prevalence of post-acute sequelae of COVID-19 (PASC), commonly known as long COVID, across the world and to assess geographic heterogeneities through a systematic review and meta-analysis. A second aim is to provide prevalence estimates for individual symptoms that have been commonly reported as PASC, based on the existing literature. Data Sources PubMed, Embase, and iSearch for preprints from medRxiv, bioRxiv, SSRN, and others, were searched on July 5, 2021 with verification extending to August 12, 2021. Study Selection Studies written in English that consider PASC (indexed as ailments persisting at least 28 days after diagnosis or recovery for SARS-CoV-2 infection) and that examine corresponding prevalence, risk factors, duration, or associated symptoms were included. A total of 40 studies were included with 9 from North America, 1 from South America, 17 from Europe, 11 from Asia, and 2 from other regions. Data Extraction and Synthesis Data extraction was performed and separately cross-validated on the following data elements: title, journal, authors, date of publication, outcomes, and characteristics related to the study sample and study design. Using a random effects framework for meta-analysis with DerSimonian-Laird pooled inverse-variance weighted estimator, we provide an interval estimate of PASC prevalence, globally, and across regions. This meta-analysis considers variation in PASC prevalence by hospitalization status during the acute phase of infection, duration of symptoms, and specific symptom categories. Main Outcomes and Measures Prevalence of PASC worldwide and stratified by regions. Results Global estimated pooled PASC prevalence derived from the estimates presented in 29 studies was 0.43 (95% confidence interval [CI]: 0.35, 0.63), with a higher pooled PASC prevalence estimate of 0.57 (95% CI: 0.45, 0.68), among those hospitalized during the acute phase of infection. Females were estimated to have higher pooled PASC prevalence than males (0.49 [95% CI: 0.35, 0.63] versus 0.37 [95% CI: 0.24, 0.51], respectively). Regional pooled PASC prevalence estimates in descending order were 0.49 (95% CI: 0.21, 0.42) for Asia, 0.44 (95% CI: 0.30, 0.59) for Europe, and 0.30 (95% CI: 0.32, 0.66) for North America. Global pooled PASC prevalence for 30, 60, 90, and 120 days after index test positive date were estimated to be 0.36 (95% CI: 0.25, 0.48), 0.24 (95% CI: 0.13, 0.39), 0.29 (95% CI: 0.12, 0.57) and 0.51 (95% CI: 0.42, 0.59), respectively. Among commonly reported PASC symptoms, fatigue and dyspnea were reported most frequently, with a prevalence of 0.23 (95% CI: 0.13, 0.38) and 0.13 (95% CI: 0.09, 0.19), respectively. Conclusions and Relevance The findings of this meta-analysis suggest that, worldwide, PASC comprises a significant fraction (0.43 [95% CI: 0.35, 0.63]) of COVID-19 tested positive cases and more than half of hospitalized COVID-19 cases, based on available literature as of August 12, 2021. Geographic differences appear to exist, as lowest to highest PASC prevalence is observed for North America (0.30 [95% CI: 0.32, 0.66]) to Asia (0.49 [95% CI: 0.21, 0.42]). The case-mix across studies, in terms of COVID-19 severity during the acute phase of infection and variation in the clinical definition of PASC, may explain some of these differences. Nonetheless, the health effects of COVID-19 appear to be prolonged and can exert marked stress on the healthcare system, with 237M reported COVID-19 cases worldwide as of October 12, 2021.


Mathematics ◽  
2021 ◽  
Vol 9 (20) ◽  
pp. 2595
Author(s):  
Jujie Wang ◽  
Shiyao Qiu

The forecast of carbon trading price is crucial to both sellers and purchasers; multi-scale integration models have been used widely in this process. However, these multi-scale models ignore the feature reconstruction process as well as the residual part and also they often focus on the linear integration. Meanwhile, most of the models cannot provide prediction interval which means they neglect the uncertainty. In this paper, an improved multi-scale nonlinear integration model is proposed. The original dataset is divided into some subgroups through variational mode decomposition (VMD) and all the subgroups will go through sample entropy (SE) process to reconstruct the features. Then, random forest and long-short term memory (LSTM) integration are used to model feature sub-sequences. For the residual part, LSTM residual correction strategy based on white noise test corrects residuals to obtain point prediction results. Finally, Gaussian process (GP) is applied to get the prediction interval estimate. The result shows that compared with some other methods, the proposed method can obtain satisfying accuracy which has the minimum statistical error. So, it is safe to conclude that the proposed method is able to efficiently predict the carbon price as well as to provide the prediction interval estimate.


Vestnik NSUEM ◽  
2021 ◽  
pp. 146-155
Author(s):  
A. V. Ganicheva ◽  
A. V. Ganichev

The problem of reducing the number of observations for constructing a confidence interval of variance with a given degree of accuracy and reliability is considered. The new method of constructing an interval estimate of variance developed in the article is formulated by three statements and justified by four proven theorems. Formulas for calculating the required number of observations depending on the accuracy and reliability of the estimate are derived. The results of the calculations are presented in the table and shown in the diagram. The universality and effectiveness of this method is shown. The universality of the method lies in the fact that it is applicable to any laws of probability distribution, and not only for the normal law. The effectiveness of the developed method is justified by comparing its performance with other known methods.


2021 ◽  
Vol 7 (3) ◽  
pp. 152-158
Author(s):  
German V. Nedugov

Background: The Henssge method is still the main thermometric method to determine postmortem interval. However, its existing software implementations are characterized by several disadvantages associated with copying simplified nomographic variants of the original mathematical models without any optimization attempts, as well as procedural imperfection in finding the roots of implicit functions. In this paper, methods are proposed for optimizing solutions to the Henssge mathematical models and determine their errors, as well as software application implementation. Aim: Optimization of the Henssge algorithm and development of a series of applications based on the obtained data, designed to determine postmortem interval. Material and methods: Methods for solving double exponential Henssge models and determining their errors based on computational mathematics and regression modeling using the least-squares method with subsequent implementation in the format of computer programs in C# language optimized. Results: The discrete nature of residual variance changes of the double exponential Henssge models intended to determine the postmortem interval according to rectal and cranioencephalic thermometry data under constant external temperature conditions is eliminated. The interval estimate determination of postmortem interval at any confidence probability is possible. The application program Warm Bodies HR was developed, which implements applied optimization methods. The application program Warm Bodies AHBG, designed to determine postmortem interval by the Henssge method in a single discrete decrease or increase conditions in the constant temperature of the external environment, including a change in the cooling conditions of the corpse, was developed. The search for the roots of implicit functions in programs is carried out using the Newton tangent method, which ensures continuous source data nature and eliminates errors associated with the need to round directly measured physical quantities. Conclusions: The developed programs are recommended for forensic medical expert practice to determine postmortem interval.


2021 ◽  
Author(s):  
James Steele ◽  
Daniel Plotkin ◽  
Derrick Van Every ◽  
Avery Rosa ◽  
Hugo Zambrano ◽  
...  

Objectives: To conduct a systematic review and multilevel meta-analysis of the current literature as to the effects of interval training (IT) vs moderate intensity continuous training (MICT) on measures of body composition, both on a whole-body and regional level. Design: Systematic review and meta-analysis. Data sources: English-language searches of PubMed/MEDLINE, Scopus, and CINAHL conducted in accordance with PRISMA guidelines. Eligibility criteria for selecting studies: a) randomized controlled trials that directly compared IT vs MICT body composition using a validated measure in healthy children and adults; b) training was carried out a minimum of once per week for at least four weeks; c) published in a peer-reviewed English language journal or on a pre-print server. Results: The main model for fat mass effects revealed a trivial standardized point estimate with high precision for the interval estimate, with negligible heterogeneity. The main model for lean mass effects revealed a trivial standardized point estimate with high precision for the interval estimate, with negligible heterogeneity. The GRADE summary of findings suggested high certainty for both main model effects. In comparison to non-intervention control groups, the IT conditions resulted in small reductions in fat mass and trivial increases in lean mass. The MICT conditions also produced small reductions in fat mass, and trivial increases in lean mass. Analysis of regional fat loss revealed trivial between group comparative treatment effects for upper body, lower body and trunk regions with minimal differences between regions. Conclusion: Our findings provide compelling evidence that the intensity of effort during endurance exercise has minimal influence on longitudinal changes in fat mass and lean mass.


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