Journal articles on the topic 'Cumulative structure function'
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Tolentino, Dante, and Sonia E. Ruiz. "Time-Dependent Confidence Factor for Structures with Cumulative Damage." Earthquake Spectra 31, no. 1 (February 2015): 441–61. http://dx.doi.org/10.1193/010912eqs008m.
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An approach is proposed to evaluate the confidence factor implicit in structures over an interval of time, considering that the structural capacity and structural demand vary simultaneously over time. A new closed-form mathematical expression of the confidence factor over a time interval is used, assuming that the structural capacity degradation is represented by a second degree polynomial function in the total interval. This formulation is made in accordance with the demand and capacity factor design format. Confidence factors at the ends of different time intervals are evaluated for an old ten-story building. The confidence factors and their confidence levels, calculated under the assumption that the structural capacity degradation follows a linear function, and alternatively, a polynomial function, are compared. The maximum difference between confidence factors assuming both types of functions is 5% after 100 years of structure construction, which represents a small difference for the engineering practice.
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Cox, Angela M., Yong Gao, Anne-Karina T. Perl, Robert S. Tepper, and Shawn K. Ahlfeld. "Cumulative effects of neonatal hyperoxia on murine alveolar structure and function." Pediatric Pulmonology 52, no. 5 (February 10, 2017): 616–24. http://dx.doi.org/10.1002/ppul.23654.
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Iyit, Neslihan. "Modelling world energy security data from multinomial distribution by generalized linear model under different cumulative link functions." Open Chemistry 16, no. 1 (April 30, 2018): 377–85. http://dx.doi.org/10.1515/chem-2018-0053.
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AbstractEnergy securityis one of the major components of energy sustainability in the world’s energy performance. In this study,energy securityis taken as an ordinal response variable coming from the multinomial distribution with the energy grade levelsA,B,C, andD. Thereafter, the worldenergy securitydata is tried to be statistically modelled by usinggeneralized linear model (GLM)approach for the ordinal response variable under different cumulative link functions. The cumulative link functions comparatively used in this study are cumulative logit, cumulative probit, cumulative complementary log-log, cumulative Cauchit, and cumulative negative log-log. In order to avoid a multicollinearity problem in the data structure, principal component analysis (PCA) technique is integrated with theGLMapproach for the ordinal response variable. In this study, statistically, the importance of determining the best cumulative link function on the accuracy of parameter estimates, confidence intervals, and hypothesis tests in theGLMfor the multinomially distributed response variable is highlighted. In terms of energy evaluation, by usingcumulative logitas the best cumulative link function,energy sources consumptions,electricity productions from nuclear energy,natural gas,oil,coal,and hydroelectric,energy use per capita and energy importsare found to have statistically significant effects onenergy securityin the world’s energy performance.
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Terek, Milan. "Regional Incomes Structure Analysis in Slovak Republic On the Basis of EU-SILC Data." Scientific Annals of Economics and Business 64, no. 2 (June 27, 2017): 171–85. http://dx.doi.org/10.1515/saeb-2017-0011.
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Abstract The paper deals with the regional incomes structure analysis in Slovak republic on the basis of European Union statistics on income and living conditions in Slovak republic data. The empirical probability mass function and empirical cumulative distribution function is constructed with aid of given sampling weights. On the basis of these functions the median, medial, standard deviation and population histogram of the whole gross household incomes for the whole Slovak republic and separately for eight Slovak regions are estimated and compared.
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Ndlovu, Bonginkosi D., Sileshi F. Melesse, Temesgen Zewotir, and Temesgen Zewotir. "A mixture model with application to discrete competing risks data." South African Statistical Journal 53, no. 2 (2019): 73–86. http://dx.doi.org/10.37920/sasj.2019.53.2.2.
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In this paper, we modify the continuous time mixture competing risks model (Larson and Dinse, 1985) to handle discrete competing risks data. The main result of the model is an alternate regression expression for the cumulative incidence function. The structure of the regression expression for the cumulative incidence function under this model, and the proportional hazards assumption for the conditional hazard rates with piece-wise constant baseline conditional hazards, combine to allow for another means to assess the covariate effects on the cumulative incidence function. This benefit comes at some computational costs because the parameters are estimated via an EM algorithm. The proposed model is applied to real data and it is found that it improves the exercise of evaluating the covariate effects on the cumulative incidence function compared to other discrete competing risks models.
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Teramoto, Kanako, Wilson Nadruz Junior, Kunihiro Matsushita, Brian Claggett, Jenine E. John, Hicham Skali, Scott Solomon, Susan Cheng, and Amil M. Shah. "Mid- to Late-Life Time-Averaged Cumulative Blood Pressure and Late-Life Cardiac Structure, Function, and Heart Failure." Hypertension 76, no. 3 (September 2020): 808–18. http://dx.doi.org/10.1161/hypertensionaha.120.14833.
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Limited data exist regarding systolic blood pressure (SBP) through mid- to late-life and late-life cardiac function and heart failure (HF) risk. Among 4578 HF-free participants in the ARIC study (Atherosclerosis Risk in Communities) attending the fifth visit (2011–2013; age 75±5 years), time-averaged cumulative SBP was calculated as the sum of averaged SBPs from adjacent consecutive visits (visits 1–5) indexed to total observation time (24±1 years). Calculations were performed using measured SBPs and also incorporating antihypertensive medication specific effect constants (underlying SBP). Outcomes included comprehensive echocardiography at visit 5 and post-visit 5 incident HF, HF with preserved ejection fraction, and reduced ejection fraction. Higher cumulative SBP was associated with greater left ventricular mass and worse diastolic measures (all P <0.001), associations that were stronger with underlying compared with cumulative SBP (all P <0.05). At 5.6±1.2 years follow-up post-visit 5, higher cumulative measured and underlying SBP were associated with incident HF (hazard ratio per 10 mm Hg for measured: 1.12 [1.01–1.24]; underlying: 1.19 [95% CI, 1.10–1.30]) and HF with preserved ejection fraction (measured: 1.15 [1.00–1.33]; underlying: 1.28 [1.14–1.45]), but not HF with reduced ejection fraction (measured: 1.11 [0.94–1.32]; underlying: 1.11 [0.96–1.24]). Associations with HF and HF with preserved ejection fraction were more robust with cumulative underlying compared with measured SBP (all P <0.05). Time-averaged cumulative SBP in mid to late life is associated with worse cardiac function and risk of incident HF, especially HF with preserved ejection fraction, in late life. These associations were stronger considering underlying as opposed to measured SBP, highlighting the importance of prevention and effective treatment of hypertension to prevent late-life cardiac dysfunction and HF.
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Jenkins, Lisanne M., Chaney R. Garner, Shawn Kurian, James P. Higgins, Todd B. Parrish, Sanaz Sedaghat, Alexander J. Nemeth, et al. "Cumulative Blood Pressure Exposure, Basal Ganglia, and Thalamic Morphology in Midlife." Hypertension 75, no. 5 (May 2020): 1289–95. http://dx.doi.org/10.1161/hypertensionaha.120.14678.
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High blood pressure (BP) negatively affects brain structure and function. Hypertension is associated with white matter hyperintensities, cognitive and mobility impairment in late-life. However, the impact of BP exposure from young adulthood on brain structure and function in mid-life is unclear. Identifying early brain structural changes associated with BP exposure, before clinical onset of cognitive dysfunction and mobility impairment, is essential for understanding mechanisms and developing interventions. We examined the effect of cumulative BP exposure from young adulthood on brain structure in a substudy of 144 (61 female) individuals from the CARDIA (Coronary Artery Risk Development in Young Adults) study. At year 30 (Y 30 , ninth visit), participants (56±4 years old) completed brain magnetic resonance imaging and gait measures (pace, rhythm, and postural control). Cumulative systolic and diastolic BP (cumulative systolic blood pressure, cDBP) over 9 visits were calculated, multiplying mean values between 2 consecutive visits by years between visits. Surface-based analysis of basal ganglia and thalamus was achieved using FreeSurfer-initiated Large Deformation Diffeomorphic Metric Mapping. Morphometric changes were regressed onto cumulative BP to localize regions of shape variation. Y 30 white matter hyperintensity volumes were small and positively correlated with cumulative BP but not gait. Negative morphometric associations with cumulative systolic blood pressure were seen in the caudate, putamen, nucleus accumbens, pallidum, and thalamus. A concave right medial putamen shape mediated the relationship between cumulative systolic blood pressure and stride width. Basal ganglia and thalamic morphometric changes, rather than volumes, may be earlier manifestation of gray matter structural signatures of BP exposure that impact midlife gait.
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Aslam, Muhammad, Muhammad Riaz, Tabassum Naz Sindhu, and Zaheer Ahmed. "A Study of Cumulative Quantity Control Chart for a Mixture of Rayleigh Model under a Bayesian Framework." Revista Colombiana de Estadística 39, no. 2 (July 18, 2016): 185. http://dx.doi.org/10.15446/rce.v39n2.58915.
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<p>This study deals with the cumulative charting technique based on a simple and a mixture of Rayleigh models. The respective charting schemes are referred as the SRCQC-chart and the MRCQC-chart. These are stimulated from existing statistical control charts in this direction i.e. the cumulative quantity control (CQC) chart, based on exponential and Weibull models, and the cumulative count control (CCC) chart, based on the simple geometricmodel. Another motivation for this study is the mixture cumulative count control (MCCC) chart based on the two component geometric model. The use of mixture cumulative quantity is an attractive approach for process monitoring. The design structure of the proposed control chart is derived by using the cumulative distribution function of simple, and two components of mixture distribution(s). We observed that the proposed charting structure is efficient in detecting the changes in process parameters. The application of the proposed scheme is illustrated using a real dataset.</p>
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Nie, Cong, Xiaoming Liu, and Serge B. Provost. "An Objective Measure of Distributional Estimability as Applied to the Phase-Type Aging Model." Risks 12, no. 2 (February 13, 2024): 37. http://dx.doi.org/10.3390/risks12020037.
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The phase-type aging model (PTAM) is a class of Coxian-type Markovian models that can provide a quantitative description of the effects of various aging characteristics. Owing to the unique structure of the PTAM, parametric inference on the model is affected by a significant estimability issue, its profile likelihood functions being flat. While existing methods for assessing distributional non-estimability require the subjective specification of thresholds, this paper objectively quantifies estimability in the context of general statistical models. More specifically, this is achieved via a carefully designed cumulative distribution function sensitivity measure, under which the threshold is tailored to the empirical cumulative distribution function, thus becoming an experiment-based quantity. The proposed definition, which is validated to be innately sound, is then employed to determine and enhance the estimability of the PTAM.
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Bow, Eric W., and John M. Rimoldi. "The Structure–Function Relationships of Classical Cannabinoids: CB1/CB2 Modulation." Perspectives in Medicinal Chemistry 8 (January 2016): PMC.S32171. http://dx.doi.org/10.4137/pmc.s32171.
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The cannabinoids are members of a deceptively simple class of terpenophenolic secondary metabolites isolated from Cannabis sativa highlighted by (-)-Δ 9 -tetrahydrocannabinol (THC), eliciting distinct pharmacological effects mediated largely by cannabinoid receptor (CB1 or CB2) signaling. Since the initial discovery of THC and related cannabinoids, synthetic and semisynthetic classical cannabinoid analogs have been evaluated to help define receptor binding modes and structure–CB1/CB2 functional activity relationships. This perspective will examine the classical cannabinoids, with particular emphasis on the structure–activity relationship of five regions: C3 side chain, phenolic hydroxyl, aromatic A-ring, pyran B-ring, and cyclohexenyl C-ring. Cumulative structure–activity relationship studies to date have helped define the critical structural elements required for potency and selectivity toward CB1 and CB2 and, more importantly, ushered the discovery and development of contemporary nonclassical cannabinoid modulators with enhanced physicochemical and pharmacological profiles.
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Hussein, Lamyaa Khalid, Huda Abdullah Rasheed, and Iden Hasan Hussein. "A Class of Exponential Rayleigh Distribution and New Modified Weighted Exponential Rayleigh Distribution with Statistical Properties." Ibn AL-Haitham Journal For Pure and Applied Sciences 36, no. 2 (April 20, 2023): 390–406. http://dx.doi.org/10.30526/36.2.3044.
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This paper deals with the mathematical method for extracting the Exponential Rayleighh distribution based on mixed between the cumulative distribution function of Exponential distribution and the cumulative distribution function of Rayleigh distribution using an application (maximum), as well as derived different statistical properties for distribution, and present a structure of a new distribution based on a modified weighted version of Azzalini’s (1985) named Modified Weighted Exponential Rayleigh distribution such that this new distribution is generalization of the distribution and provide some special models of the distribution, as well as derived different statistical properties for distribution
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Wang, Ai Hong, Ge Ning Xu, Ping Yang, and You Shan Gao. "Research on Random Stress Spectrum for Cumulative Fatigue of Crane Metal Structure." Advanced Materials Research 189-193 (February 2011): 1122–26. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.1122.
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In order to calculate the fatigue life, lifting or unloading position, lifting weight and load mobile line of crane with automatic acquisition device were recorded on spot. Probability distribution model and its characteristic parameters of lifting weight and lifting or unloading position were analyzed with goodness of fit test. The random samples of the load spectrum parameters for the cumulative fatigue were also calculated with Latin Hypercube Sampling. Dynamic simulation model of crane metal structure was formed. Dynamic load function that dynamic load changed with time was also established, from which the stress spectrum through structural dynamics analysis in fatigue calculation point was acquired. Based on then above calculation, the remaining fatigue life of the prototype is 38 years.
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Wang, Yi Dong, Yi Zhou He, Hai Bo Liu, and Jun Wei Lei. "The Research on Degradation Failure Life and Degradation Data Structure." Advanced Materials Research 710 (June 2013): 294–97. http://dx.doi.org/10.4028/www.scientific.net/amr.710.294.
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In order to solve the reliability assessment in the case of competition failure induced by the coexistence between burst-type failure and degradation-type failure in the product, the method of degradation amount distribution was adopted to describe the degradation process of performance in product. Considering the relativity between sudden failure and degradation degree, the cumulative distribution function of sudden failure was calculated from the standpoint of degradation amount. Eliminating the affect of sudden failure according to a certain conditional probability in the degradation amount distribution function, which helps to realize reliability assessment based on competitive failure analysis.
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Xin, Dai, and Tianshan Ma. "Commuter Travel Behavior Modeling in Metropolitan Areas Based on Cumulative Prospect Theory: A Case Study of Xi’an, China." Complexity 2024 (January 30, 2024): 1–10. http://dx.doi.org/10.1155/2024/8867264.
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A metropolitan area is a new form of urban development under the agglomeration effect and scale economy. The renewal and upgrading of urban spatial structures have brought new pressure to urban commuting. Under the new form of the metropolitan area, the process of regional integration has accelerated, and long-distance extreme commuting has increased. New changes have taken place in the travel structure. This paper constructs a travel behavior selection model for office workers based on the cumulative prospect theory, introduces the value of commuting travel time into the generalized travel cost function, uses the weight function and the improved generalized travel cost function as the basis of the transportation mode selection model, defines the reference point of the generalized travel cost in the model, and selects the prospect with the largest cumulative prospect value as the optimal decision for travelers. Based on the “expected utility maximization theory” and the “cumulative prospect theory,” the commuter is simulated under four different travel scenarios to study the optimal traffic mode selection behavior. The results show that under the framework of expected utility theory, the travel mode choice behavior of commuters is not affected by travel scenarios, and the cumulative prospect theory is more suitable for the study of travel mode choice behavior. The construction of a transportation mode selection model with the value of commuting travel time as the core variable can help commuters to choose a reasonable transportation mode and provide a basis for the government and relevant departments to formulate traffic management plans and implement traffic congestion mitigation policies.
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Lupenko, Serhii, Nadiia Lutsyk, Oleh Yasniy, and Łukasz Sobaszek. "Statistical Analysis of Human Heart Rhythm with Increased Informativeness." Acta Mechanica et Automatica 12, no. 4 (December 1, 2018): 311–15. http://dx.doi.org/10.2478/ama-2018-0047.
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Abstract The new methods of statistical analysis of heart rhythm were developed based on its generalized mathematical model in a form of random rhythm function, that allows to increase the informativeness and detailed analysis of heart rhythm in cardiovascular information systems. Three information criteria (BIC, AIC and AICc) were used to determine the cumulative distribution functions that best describe the sample and to assess the unknown parameters of distributions. The usage of the rhythm function to analyse heart rhythm allows to consider much better its time structure that is the basis to improve the accuracy of diagnosis of cardiac rhythm.
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Guo, Rui Feng, and Peng Li Wang. "Application of Power Spectral Density Method to Fatigue Life Estimation of the Axle Structure." Applied Mechanics and Materials 487 (January 2014): 272–75. http://dx.doi.org/10.4028/www.scientific.net/amm.487.272.
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Based on the random vibration theory, fatigue strength theory and Miner cumulative damage theory, the formulas for estimation of fatigue life which can be coped with narrowband and broadband random vibration was derived by the peak distribution function. The power spectral density function of axle structure is deduced after the power spectral density of standard road and the vibration model of wheel had studying. Combined the power spectral density function with broadband random vibration fatigue life estimation formula, the fatigue life of axle structure was obtained. This method is simple and has a strong engineering practicality.
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Bhattacharya, Debswapna. "refineD: improved protein structure refinement using machine learning based restrained relaxation." Bioinformatics 35, no. 18 (February 13, 2019): 3320–28. http://dx.doi.org/10.1093/bioinformatics/btz101.
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AbstractMotivationProtein structure refinement aims to bring moderately accurate template-based protein models closer to the native state through conformational sampling. However, guiding the sampling towards the native state by effectively using restraints remains a major issue in structure refinement.ResultsHere, we develop a machine learning based restrained relaxation protocol that uses deep discriminative learning based binary classifiers to predict multi-resolution probabilistic restraints from the starting structure and subsequently converts these restraints to be integrated into Rosetta all-atom energy function as additional scoring terms during structure refinement. We use four restraint resolutions as adopted in GDT-HA (0.5, 1, 2 and 4 Å), centered on the Cα atom of each residue that are predicted by ensemble of four deep discriminative classifiers trained using combinations of sequence and structure-derived features as well as several energy terms from Rosetta centroid scoring function. The proposed method, refineD, has been found to produce consistent and substantial structural refinement through the use of cumulative and non-cumulative restraints on 150 benchmarking targets. refineD outperforms unrestrained relaxation strategy or relaxation that is restrained to starting structures using the FastRelax application of Rosetta or atomic-level energy minimization based ModRefiner method as well as molecular dynamics (MD) simulation based FG-MD protocol. Furthermore, by adjusting restraint resolutions, the method addresses the tradeoff that exists between degree and consistency of refinement. These results demonstrate a promising new avenue for improving accuracy of template-based protein models by effectively guiding conformational sampling during structure refinement through the use of machine learning based restraints.Availability and implementationhttp://watson.cse.eng.auburn.edu/refineD/.Supplementary informationSupplementary data are available at Bioinformatics online.
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Nguyen, Thanh Q., and Hoang B. Nguyen. "Structural health monitoring of bridge spans using Moment Cumulative Functions of Power Spectral Density (MCF-PSD) and deep learning." Bridge Structures 17, no. 1-2 (June 11, 2021): 15–39. http://dx.doi.org/10.3233/brs-210183.
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This article proposes a new parameter in evaluating mechanical behaviors of defected bridge spans. It is Moment Cumulative Function of Power Spectral Density (MCF-PSD) based on changes in shape of power spectrum and trained via cumulative function of spectral moment value by deep learning model. This new parameter allows evaluating stiffness attenuation along time, thereby helps to forecast the workability of bridge span. It can identify risky positions in not only a bridge span but also various spans of the same bridge, which proves its sensitivity to the structure’s behavior change over time. This study reveals that training MCF-PSD using cumulative function algorithm has gained outstanding results in comparison with previous studies in structural quality assessment. Therefore, it fulfills criteria of evaluating the damage level in a structure and also fosters new development of defect diagnosis and forecast. Conclusions from this study show that the change of this function is the basis to evaluate difference among measurement positions in the same span or among different spans of the same bridge and behaviors at different positions in the same span. Therefore, MCF-PSD is more sensitive than other parameters in evaluating the structure’s stiffness attenuation.
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Yang, Guang Wu, and Shou Ne Xiao. "Research on Simulation of Fatigue Reliability Based on Rainflow Counting Range." Advanced Materials Research 44-46 (June 2008): 317–22. http://dx.doi.org/10.4028/www.scientific.net/amr.44-46.317.
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In order to evaluate fatigue reliability of single structure under random load, based on rainflow counting range of stress-time history, fatigue strength reliability of structure is obtained by means of stress-strength interference theory and Dirlik’s probability density function of rainflow counting range, as well as by assuming that fatigue limit accords with normal distribution. Also by using Miner’s damage cumulative theory, assuming that fatigue life accords with lognormal distribution, and taking into account dispersion of damage cumulative criterion value, given finite life reliability of structure is obtained by means of Monte-Carlo simulation method. The results show that although maximum range in stress-time history is greater than fatigue limit, when a majority of cycle range in stress-time history is less than fatigue limit, structure has high reliability of fatigue strength. The results of given finite life reliability indicate that although structure has high reliability fatigue strength under single stress-time history, fatigue reliability of structure experiencing many cycles will gradually decrease.
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Wang, Feifei, Jinggan Shao, Wenkai Li, Longfei Wang, Yafei Wang, and Honglin Liu. "Numerical Simulation Study on Lining Damage of Shield Tunnel under Train Load." Sustainability 14, no. 21 (October 27, 2022): 14018. http://dx.doi.org/10.3390/su142114018.
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Under the long-term dynamic load influence of trains, shield tunnel structures are damaged. With the increase in operating number, cumulative damage gradually increases. When cumulative damage increases to a certain value, the tunnel lining produces cracks and loses tensile strength, which leads to tunnel deformation, damage, etc. In serious cases, the tunnel ceases operation, causing traffic accidents and casualties. Based on the finite element software ABAQUS, this paper analyses the change rule of tunnel lining damage under long-term dynamic train load and explores the influence of tunnel buried depth on the change rule of tunnel lining damage. The excitation force function is used to generate a series of dynamic and static loads superimposed by sine functions to simulate the dynamic loads of trains. Load is applied above the tunnel by writing DLOAD subprogram. The results show that the damage of tunnel lining mainly occurs at the arch foot and the structural damage in other places can be neglected. Under the same loading condition, the greater the tunnel lining damage is. Under the same loading conditions, the tunnel lining damage increases with the increase in buried depth. According to the test results, the mathematical expressions of cumulative damage value versus loading times at the location prone to fatigue damage. It provides theoretical reference for safety evaluation and protection of tunnel structure under long-term train load.
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Long, Xueqin, Chenxi Hou, Shanshan Liu, and Yuejiao Wang. "Sequential Route Choice Modeling Based on Dynamic Reference Points and Its Empirical Study." Discrete Dynamics in Nature and Society 2020 (March 27, 2020): 1–11. http://dx.doi.org/10.1155/2020/8081576.
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Aiming at the influence of information, we investigate and analyze the sequential route choice behavior under dynamic reference points based on cumulative prospect theory in this paper. An experiment platform collecting the sequential route choices based on C/S structure is designed and four types of information are released to participants, respectively. Real-time travel time prediction methods are then proposed for travelers’ decision-making. Using nonlinear regression method, the parameters of the value function and weight function of cumulative prospect theory are estimated under different types of information, respectively. It is found that travelers’ behavior showed obvious characteristic of risk pursuit under the circumstance where real-time travel time information is released. Instead, when they have access to descriptive information, they tend to be more conservative.
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Liu, Qiang, Longfei Xie, and Fengri Li. "The Spatial Distribution of the Needle Area of Planted Larix olgensis Trees." Forests 10, no. 1 (January 4, 2019): 28. http://dx.doi.org/10.3390/f10010028.
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The spatial distribution of leaf area largely governs both the structure and function of a tree crown. Three sample trees were selected from a 16-year-old Larix olgensis plantation in the Maoershan Forest Farm, Heilongjiang Province, based on the average diameter at breast height in each plot. All needles from the branches in the nodal and internodal pseudowhorls within the crown were destructively sampled. The crown was divided into several segments in the vertical and horizontal directions, resulting in different sub-regions. The needle area (NA) in each sub-region was computed based on the needle mass per area (NMA). The vertical and horizontal distributions and their cumulative NA distributions were characterized using the Weibull distribution function and its cumulative form. A two-dimensional NA model was created by combining the two Weibull distribution functions of the vertical and horizontal distributions. The variation in the spatial distribution of the NA among the different crown directions is discussed, and the influence of competition from competitors on the spatial distribution of NA was analyzed. The results showed that the Weibull distribution function and its cumulative form performed well in describing the vertical and horizontal distributions and the cumulative distributions of the NA, which was generally concentrated upward within the crown. This phenomenon was most apparent in dense stands with strong competition. The center of the NA exhibited an inward shift in the horizontal direction within the crown but shifted outwards with an increase in competition. The cumulative vertical and horizontal distributions of the NA obviously varied with different crown directions, which was associated mainly with the light conditions. The two-dimensional NA patterns showed that the center of the NA generally shifted outward with an increase in the relative depth into the crown (RDINC), and that more concentrated and more skewed patterns usually occurred under increased competition. Different crown directions exhibited different two-dimensional NA patterns, but the core driver was the variable light condition caused by the competitors, particularly in closed stands.
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Jiang, Hong Tao, Chun Rong Guo, Chun Xing Hai, Shan Shan Sun, Yun Hu Xie, and Jun Xiu Liu. "The Wind-Sand Flux Structure of Grassland on the Northern Foot of Yinshan Mountain." Applied Mechanics and Materials 668-669 (October 2014): 1530–37. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.1530.
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Sand samplers were layed out in the grassland located in the northern foot of Yinshan Mountain for collecting soil flux samples from 0 to 1.5m height above the surface from Mar., 1, 2008 to Feb., 29, 2009.Exponential and Power functions were both used for describing vertical distribution of sand flux in the grassland, the results indicated that determination coefficient of Power function varied from 0.898 to 0.992 while 0.432 to 0.661 for exponential function. Power function is better than exponential function in describing the vertical distribution of both annual and seasonal soil flux, summer excluded. Annual cumulative percentage of each height was determined indirectly according to the power function mentioned above, the result indicated that up to 2m height,15-25% of soil flux concentrated with in 10cm above the surface,25-35% of soil flux concentrated within 20cm above the surface,30-40% of soil flux concentrated within 30 cm above the surface, 43-54% of soil flux concentrated within 50 cm above the surface,85-90% of soil flux concentrated within 150 cm above the surface, respectively. No significant differences of soil flux structures in spring, autumn, winter and in the whole year were found. The research on wind erosion of grassland in the vertical direction more dispersed, in the height range of sediment accumulated percentage was lower than that of the previous research.
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Williams, E. Jay, Glenn O. Ware, Jia-Yee Lai, and J. Stanley Drexler. "Effect of Pod Maturity and Plant Age on Pod and Seed Size Distributions of Florunner Peanuts." Peanut Science 14, no. 2 (July 1, 1987): 79–83. http://dx.doi.org/10.3146/i0095-3679-14-2-7.
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Abstract Florunner peanut pods (Arachis hypogaea L.) were sampled at nine weekly intervals from 92 to 148 days after planting (DAP) in crop year 1979. The fresh pods were divided into six maturity categories according to the color and structure of the mesocarp. After drying, individual pods and seed for each maturity class and date were sized over a series of screen slots conforming to official grade standards. The cumulative distribution function (CDF) for the logistic distribution was used to quantify the cumulative percentage by weight of pods and seed which rode a designated screen. The parameters of the logistic CDF were regressed separately by maturity class as functions of plant age. These relationships provide a mathematical approach for a better understanding of the influence of pod maturity and plant age on pod and seed sizes.
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Sága, Milan, Peter Pecháč, and Lenka Jakubovičová. "Application of Multi-Criteria Optimization to Large-Scale Structures Design." Applied Mechanics and Materials 693 (December 2014): 171–76. http://dx.doi.org/10.4028/www.scientific.net/amm.693.171.
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The paper presents fundamental principles and application of the large-scale truss structure PKP25-20i optimal design based on a multi-criteria optimization algorithm. The multi-objective function contains conditions for deformation, stability and cumulative damage obtained by finite element analyses. The whole process was implemented and realized in special Matlab’s procedures and FEM software Cosmos/M.
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Dang, Thuat-Cong, Thien-Phu Le, and Pascal Ray. "Seismic fragility curves based on the probability density evolution method." Vietnam Journal of Mechanics 39, no. 2 (June 21, 2017): 177–89. http://dx.doi.org/10.15625/0866-7136/10208.
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A seismic fragility curve that shows the probability of failure of a structure in function of a seismic intensity, for example peak ground acceleration (PGA), is a powerful tool for the evaluation of the seismic vulnerability of the structures in nuclear engineering and civil engineering. The common assumption of existing approaches is that the fragility curve is a cumulative probability log-normal function. In this paper, we propose a new technique for construction of seismic fragility curves by numerical simulation using the Probability Density Evolution Method (PDEM). From the joint probability density function between structural response and random variables of a system and/or excitations, seismic fragility curves can be derived without the log-normal assumption. The validation of the proposed technique is performed on two numerical examples.
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CATRAKIS, HARIS J., ROBERTO C. AGUIRRE, and JESUS RUIZ-PLANCARTE. "Area–volume properties of fluid interfaces in turbulence: scale-local self-similarity and cumulative scale dependence." Journal of Fluid Mechanics 462 (July 10, 2002): 245–54. http://dx.doi.org/10.1017/s0022112002008911.
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Area–volume properties of fluid interfaces are investigated to quantify the scale-local and cumulative structure. An area–volume density g3(λ) and ratio Ω3(λ) are introduced to examine the interfacial behaviour as a function of scale λ or across a range of scales, respectively. These measures are demonstrated on mixed-fluid interfaces from whole-field ∼10003 three-dimensional space–time concentration measurements in turbulent jets above the mixing transition, at Re ∼ 20000 and Sc ∼ 2000, recorded by laser-induced-fluorescence and digital-imaging techniques, with Taylor's hypothesis applied. The cumulative structure is scale dependent in Ω3(λ), with a dimension D3(λ) that increases with increasing scale. In contrast, the scale-local structure exhibits self-similarity in g3(λ) with an exponent αg ≈1.3 for these interfaces. The scale dependence in the cumulative structure arises from the large scales, while the self-similarity corresponds to the small-scale area–volume contributions. The small scales exhibit the largest area–volume density and provide the dominant contributions to the total area–volume ratio, which corresponds to ∼10 times the area of a purely large-scale interface for the present flow conditions. The self-similarity in the scale-local structure at small scales provides the key ingredient to extrapolate the area–volume behaviour to higher Reynolds numbers.
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Alberto Peña-Guillén, Jesús, Josefa Ramoni-Perazzi, and Giampaolo Orlandoni-Merli. "A bivariate survival model for events with dependent failure times based on Archimedean copula functions. Application case: A sample of HIV patients." Brazilian Journal of Biometrics 42, no. 1 (March 15, 2024): 50–58. http://dx.doi.org/10.28951/bjb.v42i1.644.
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This paper proposes a bivariate survival model for dependent failure times based on copula functions of the Archimedean family and the mean cumulative function for non-recurrent events of different types (MCFR ̅E) and uses it to estimate the probability of survival from the occurrence of events of different types on the same HIV/AIDS patient. The copula functions evaluate the dependence structure between the failure times of the events experienced by the same patient throughout their follow-up period, and the MCFR ̅E generates the marginal survival function for each event. The marginal function is a nonparametric estimator that gives the same estimated survival probability as the Kaplan-Meier estimator if the failure times of the different types of events are independent. If each patient experiences at least one event, a subset of them generates a compound event that affects the estimated probability of survival. The results show that the traditionally estimated survival probabilities are biased if dependent failure times are treated as independent.
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Weber, W. J. "Radiation-induced defects and amorphization in zircon." Journal of Materials Research 5, no. 11 (November 1990): 2687–97. http://dx.doi.org/10.1557/jmr.1990.2687.
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The effects of self-radiation damage as a function of cumulative alpha-decay events in synthetic zircon doped with 238Pu and natural zircons damaged over geologic time are compared and interpreted in terms of the accumulation of both defects and amorphousness. The radiation-induced unit-cell expansion and amorphization result in macroscopic swelling that increases sigmoidally with cumulative decay events and saturates at a fully amorphous state. The derived amorphous fraction as a function of cumulative dose is consistent with models based on the multiple overlap of displacement cascades, indicating that amorphization in zircon occurs as a result of the local accumulation of high defect concentrations rather than directly within a displacement cascade. Annealing of point defects in the natural zircons suppresses initial swelling and delays the onset of amorphization. Full recrystallization of the zircon structure from the amorphous state occurs in two stages, with kinetics and activation energies consistent with the reported thermal stability of the amorphous state. This study further confirms that actinide doping is a viable accelerated technique to study or simulate radiation effects from alpha decay on geologic time scales.
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Shen, Zhao Wei, Xiao Hong Wang, and Wei Liang Jin. "Study on Combination Method of Stochastic Load Processes." Advanced Materials Research 915-916 (April 2014): 82–85. http://dx.doi.org/10.4028/www.scientific.net/amr.915-916.82.
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When more than one loads act on a structure,the combination of stochastic loads is generally considered in the design of the structure,Based on the theoretical derivation and numerical calculation analysis to the process of two common loads in Poisson square wave and Poisson impulse this paper presents the combination method of loads.i.e. The maximum intensity function of load combination is expressed by the cumulative distribution function in the limit state design. In addition,the result calculated during the limit state design is compared with those calculated by Turkstra and Monte Carlo methods and the analytical results show that the method proposed in this paper is feasible in the calculation of load combination.
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Chesneau, Christophe, Subrata Chakraborty, Hassan S. Bakouch, and Kadir Karakaya. "A new symmetric distribution on integers with applications in data modeling and zero inflated regression." Journal of Statistics & Management Systems 26, no. 2 (2023): 291–308. http://dx.doi.org/10.47974/jsms-865.
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In this paper, a symmetric discrete distribution on integers is proposed by using a novel method of generating new distribution on Z. This distribution has only one parameter and possesses a very simple structure. Many important characteristics, such as, the recurrence relation, tail length, mode, Cumulative distribution function, monotonic property of log-concavity, moments and generating functions, are investigated. Maximum likelihood estimation of the model parameter is presented. An innovative zero-inflated count regression analysis is introduced based on the proposed distribution. The utility of this model is justified by considering three applications of count data modeling and regression in comparison to some established count distributions on Z.
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Wang, Qiang, and Ziyan Wu. "Multidimensional Fragility Analysis for a NEES Frame Structure by Integrating a New Energy Damage Index: Cumulative Plastic Strain." Advances in Civil Engineering 2019 (June 26, 2019): 1–11. http://dx.doi.org/10.1155/2019/7323656.
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Cumulative plastic strain (CPS) damage index is proposed in this study for seismic fragility analysis by integrating the force analogy method into the energy balance equation, and CPS can be defined as the ratio of the demand of plastic dissipation energy to its capacity. The cumulative plastic strain can indicate the structural damage cumulative effect under earthquakes, which makes it especially suitable to be selected as the damage index for the structural component. Threshold values of cumulative plastic strain for different performance limit state (PLS) levels are obtained through the degree of consistency of interstory drift-based fragility curves and CPS-based fragility curves. Regarding the multidimensional fragility evaluation, CPS and the floor acceleration will be selected as the quantification indices for performance limit state of the structural component and nonstructural component, respectively. The probabilistic seismic demand model (PSDM) following multivariate logarithmic normal distribution will be developed, and taking PLS uncertainty and correlation into consideration, multidimensional PLS function is constructed to identify the structural failure domain. A full-scale 2-bay 2-story frame structure for the Network for Earthquake Engineering Simulation (NEES) project is employed as the case study structure to demonstrate the proposed theory. Nonlinear dynamic time-history analysis is carried out for the structure to obtain its maximum responses under earthquakes. Consequently, the multidimensional fragility curves can be derived on the basis of CPS. Besides, the influence of PLS threshold value, engineering demand parameter (EDP) correlation, and PLS correlation on the multidimensional fragility is investigated. Results show that (1) CPS damage index can fully consider the cumulative effect of damage under earthquakes, which makes up for the deficiency of the interstory drift damage index in this aspect, (2) the multidimensional fragility framework can deal with the PLS correlation and EDP correlation simultaneously, which will generate a more precise seismic damage assessment result, and (3) multidimensional fragility is sensitive to PLS threshold values and PLS correlation parameters.
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Fahlman, G. G., H. B. Richer, R. I. Ibata, N. C. Ivanans, G. Mandushev, J. E. Hesser, P. B. Stetson, et al. "HST Observations of the Globular Cluster M4." Symposium - International Astronomical Union 174 (1996): 39–48. http://dx.doi.org/10.1017/s0074180900001364.
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The WFPC2 aboard the Hubble Space Telescope has been used to obtain deep images in three fields at different radial positions in the nearest Globular cluster, M4 (NGC 6121). In this paper, we discuss the white dwarf cooling sequence and show how the dynamical structure of the cluster will affect their cumulative distribution function. We also present the first discussion of our observations of the faint cluster main sequence stars.
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Pindus, Dominika M., Ana Selzer-Ninomiya, Apurva Nayak, JJ Pionke, and Lauren B. Raine. "Effects of reducing sedentary behaviour duration by increasing physical activity, on cognitive function, brain function and structure across the lifespan: a systematic review protocol." BMJ Open 12, no. 10 (October 2022): e046077. http://dx.doi.org/10.1136/bmjopen-2020-046077.
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IntroductionGreater engagement in sedentary behaviours has been related to poorer cognitive functions in epidemiological research. However, the effects of reducing sedentary behaviour duration on cognitive function, brain function, and structure remain poorly understood. This systematic review aims to synthesise the evidence on the effects of reducing sedentary behaviour duration by increasing time spent in physical activity on cognitive function, brain structure and function in apparently healthy children, adolescents and adults.Methods and analysisThe protocol follows Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The literature search will be conducted (search dates: August–September 2022) across six databases: PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature (via EBSCO Host), PsycINFO (via ProQuest), SPORTDiscus and Web of Science (Science and Social Science Citation Index). The inclusion criteria are as follows: randomised and non-randomised experimental studies as defined by the Cochrane Handbook, published in English, in peer-reviewed journals, and as theses or dissertations. References of included papers will be screened for additional studies. Acute and chronic interventions targeting children (≥ 4 years), adolescents, younger adults (≥ 18–40 years), middle-aged (40–64 years) and older adults (65+ years) will be eligible. Methodological quality will be assessed with the Effective Public Health Practice Project quality assessment tool for quantitative studies. Qualitative synthesis will be stratified by intervention type (acute vs chronic), intervention content (reducing sedentary time or interrupting prolonged sitting) and outcome (cognitive, brain structure and function).Ethics and disseminationNo primary data collection will be conducted as part of this systematic review. Study findings will be disseminated through peer-reviewed publications, conference presentations and social media.PROSPERO registration numberCRD42020200998.
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Matras, Yaron. "Mixed languages: a functional–communicative approach." Bilingualism: Language and Cognition 3, no. 2 (August 2000): 79–99. http://dx.doi.org/10.1017/s1366728900000213.
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It has been suggested that the structural composition of mixed languages and the linguistic processes through which they emerge are to some extent predictable, and that they therefore constitute a language “type” (e.g. Bakker and Mous, 1994b; Bakker and Muysken, 1995). This view is challenged here. Instead, it is argued that the compartmentalisation of structures observed in mixed languages (i.e. the fact that certain structural categories are derived from one “parent” language, others from another) is the result of the cumulative effect of different contact mechanisms. These mechanisms are defined in terms of the cognitive and communicative motivations that lead speakers to model certain functions of language on an alternative linguistic system; each mechanism will typically affect particular functional categories. Four relevant processes are identified: lexical re-orientation, selective replication, convergence, and categorial fusion. Different combinations of processes will render different outcomes, hence the diversity of mixed languages as regards their structure, function, and development.
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Pavlovic, D., N. Viires, C. Zedda, M. Fournier, and M. Aubier. "Effects of corticosteroids on epithelial structure and smooth muscle function of rat trachea." European Respiratory Journal 11, no. 3 (March 1, 1998): 575–82. http://dx.doi.org/10.1183/09031936.98.11030575.
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Corticosteroids, efficient drugs for the treatment of severe asthma, may have numerous side effects. We investigated the effects of 7 days of treatment with triamcinolone (1.2 mg x kg(-1) x day(-1)) on the epithelial structure, tracheal smooth muscle cross-sectional area and contractility in the rat. The corticosteroid-injected rats were compared to pair-fed, and pair-weighed animals. Histological studies were performed on transverse sections of glutaraldehyde-fixed tracheal blocks embedded in plastic. In the preparations taken from corticosteroid-injected, pair-fed and pair-weighed animals, pharmacological stimulation with single (10(-3) M) or cumulative (10(-8)-10(-3) M) concentrations of carbachol (in corticosteroid-injected and pair-fed animals), either inside (In) or outside (Out) of the tracheal lumen, was performed and contractions of the tracheal smooth muscle were recorded. We found that triamcinolone administration: 1) reduced the number of epithelial cells and the tracheal smooth muscle cross-sectional area; 2) induced a decrease in maximal tension (Tmax (g); Out: 2.42+/-0.17, 1.03+/-0.1 in pair-fed and corticosteroid-injected, respectively; In: 2.55+/-0.16, 1.1+/-0.16, respectively) without affecting the sensitivity of the tracheal smooth muscle; and 3) reduced the time required to reach 50% Tmax in carbachol (In) preparations. We conclude that the observed changes resulted from atrophy of tracheal smooth muscle induced by undernutrition and atrophy of tracheal smooth muscle and tracheal epithelium induced by corticosteroid treatment.
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Saih, Asmae, Hana Baba, Meryem Bouqdayr, Hassan Ghazal, Salsabil Hamdi, Anass Kettani, and Lahcen Wakrim. "In Silico Analysis of High-Risk Missense Variants in Human ACE2 Gene and Susceptibility to SARS-CoV-2 Infection." BioMed Research International 2021 (April 7, 2021): 1–10. http://dx.doi.org/10.1155/2021/6685840.
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SARS-CoV-2 coronavirus uses for entry to human host cells a SARS-CoV receptor of the angiotensin-converting enzyme (ACE2) that catalyzes the conversion of angiotensin II into angiotensin (1-7). To understand the effect of ACE2 missense variants on protein structure, stability, and function, various bioinformatics tools were used including SIFT, PANTHER, PROVEAN, PolyPhen2.0, I. Mutant Suite, MUpro, SWISS-MODEL, Project HOPE, ModPred, QMEAN, ConSurf, and STRING. All twelve ACE2 nsSNPs were analyzed. Six ACE2 high-risk pathogenic nsSNPs (D427Y, R514G, R708W, R710C, R716C, and R768W) were found to be the most damaging by at least six software tools (cumulative score between 6 and 7) and exert deleterious effect on the ACE2 protein structure and likely function. Additionally, they revealed high conservation, less stability, and having a role in posttranslation modifications such a proteolytic cleavage or ADP-ribosylation. This in silico analysis provides information about functional nucleotide variants that have an impact on the ACE2 protein structure and function and therefore susceptibility to SARS-CoV-2.
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Sha, Yun Dong, Zhen Zhang, Feng Tong Zhao, and Jing Wei. "Estimation of Random Sonic Fatigue Life Based on Peak Probability Density of Von Mises Stress." Advanced Materials Research 199-200 (February 2011): 913–21. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.913.
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As to the random sonic fatigue problem of thin walled structure of aerospace flight vehicle, estimation method for fatigue life based on Von Mises stress peak probability density is investigated. Assuming that Von Mises stress process satisfies three-parameter Weibull distribution, the peak probability density function of Von Mises stress is derived through the threshold crossing analysis and the peak distribution analysis of stationary random process. According to the Miner linear cumulative damage theory, the method for estimating the fatigue life in the frequency domain is established with the Von Mises stress peak probability density function applied. As an example, an aero-engine Combustor liner is considered, using coupled Finite Element Method (FEM) and Boundary Element Method (BEM) method, the structure vibration response to limited bandwidth Gaussian white noise is calculated. Based on the results, fatigue life of the structure is estimated by using the proposed method. Further more, the influences of the probability density function which is characterized by three-parameter Weibull distribution and two-parameter Weibull distribution respectivily for Von Mises stress response of the Combustor liner structure subjected to random accoustic loadings are discussed.
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Beaulieu, Marie-Eve, Francisco Castillo, and Laura Soucek. "Structural and Biophysical Insights into the Function of the Intrinsically Disordered Myc Oncoprotein." Cells 9, no. 4 (April 22, 2020): 1038. http://dx.doi.org/10.3390/cells9041038.
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Myc is a transcription factor driving growth and proliferation of cells and involved in the majority of human tumors. Despite a huge body of literature on this critical oncogene, our understanding of the exact molecular determinants and mechanisms that underlie its function is still surprisingly limited. Indubitably though, its crucial and non-redundant role in cancer biology makes it an attractive target. However, achieving successful clinical Myc inhibition has proven challenging so far, as this nuclear protein is an intrinsically disordered polypeptide devoid of any classical ligand binding pockets. Indeed, Myc only adopts a (partially) folded structure in some contexts and upon interacting with some protein partners, for instance when dimerizing with MAX to bind DNA. Here, we review the cumulative knowledge on Myc structure and biophysics and discuss the implications for its biological function and the development of improved Myc inhibitors. We focus this biophysical walkthrough mainly on the basic region helix–loop–helix leucine zipper motif (bHLHLZ), as it has been the principal target for inhibitory approaches so far.
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Tran-The, Hung, Sunil Gupta, Santu Rana, and Svetha Venkatesh. "Trading Convergence Rate with Computational Budget in High Dimensional Bayesian Optimization." Proceedings of the AAAI Conference on Artificial Intelligence 34, no. 03 (April 3, 2020): 2425–32. http://dx.doi.org/10.1609/aaai.v34i03.5623.
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Scaling Bayesian optimisation (BO) to high-dimensional search spaces is a active and open research problems particularly when no assumptions are made on function structure. The main reason is that at each iteration, BO requires to find global maximisation of acquisition function, which itself is a non-convex optimization problem in the original search space. With growing dimensions, the computational budget for this maximisation gets increasingly short leading to inaccurate solution of the maximisation. This inaccuracy adversely affects both the convergence and the efficiency of BO. We propose a novel approach where the acquisition function only requires maximisation on a discrete set of low dimensional subspaces embedded in the original high-dimensional search space. Our method is free of any low dimensional structure assumption on the function unlike many recent high-dimensional BO methods. Optimising acquisition function in low dimensional subspaces allows our method to obtain accurate solutions within limited computational budget. We show that in spite of this convenience, our algorithm remains convergent. In particular, cumulative regret of our algorithm only grows sub-linearly with the number of iterations. More importantly, as evident from our regret bounds, our algorithm provides a way to trade the convergence rate with the number of subspaces used in the optimisation. Finally, when the number of subspaces is "sufficiently large", our algorithm's cumulative regret is at most O*(√TγT) as opposed to O*(√DTγT) for the GP-UCB of Srinivas et al. (2012), reducing a crucial factor √D where D being the dimensional number of input space. We perform empirical experiments to evaluate our method extensively, showing that its sample efficiency is better than the existing methods for many optimisation problems involving dimensions up to 5000.
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Sun, Jingjing, and Yi Lin. "Assessing the Allometric Scaling of Vectorized Branch Lengths of Trees with Terrestrial Laser Scanning and Quantitative Structure Modeling: A Case Study in Guyana." Remote Sensing 15, no. 20 (October 18, 2023): 5005. http://dx.doi.org/10.3390/rs15205005.
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Allometric scaling is closely related to the morphology, function and behavior of trees, which are of great significance to the study of ecology. However, most of the traditional allometric scaling studies used the scalar attributes of trees, without considering the 3D vector mode of tree growth. In order to investigate the allometric relationships between branch lengths in 3D vector mode, in this study, an accurate and detailed quantitative structure model was used to reconstruct tree architectures from 3D point cloud data collected by terrestrial laser scanning and extract the structural parameters of each branch (length, branching level and zenith angle). The standardized major axis was used to establish and analyze the scalar and vector allometric relationships between branch lengths. Our results show that at the same branching level and using the same allometric model, the scaling exponents between the lengths of branches and the lengths of cumulative child (descendant) branches (no matter whether the lengths are in scalar or vector form) are similar among trees, and there is no significant difference between the scaling exponents of most trees. And the scaling exponents between the lengths of the horizontal components of branches and the cumulative lengths of the horizontal components of the child (descendant) branches are much larger than those between the lengths of the vertical components of branches and the cumulative lengths of vertical components of the child (descendant) branches. At different branching levels, the scaling exponents between the lengths of branches and the cumulative lengths of descendant branches tend to decrease with the increase in the branching level. The allometric models in terms of the cumulative lengths of horizontal components of the child (descendant) branches and the allometric models in terms of the cumulative lengths of child (descendant) branches have similar model accuracy and scaling exponents. The study results of allometric relationships between tree branch lengths in 3D mode are of great importance for understanding the crown morphology and the branching rule, which is helpful to further understand the growth strategies and adaptation mechanisms of trees and explain the growth and development mechanisms of trees from a physiological perspective.
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Clarke, Raymond, Hemna Govindaraju, Martina Beretta, Ellen Olzomer, Adam Lawther, Adam Walker, Zhiming Fang, et al. "Immp2l Enhances the Structure and Function of Mitochondrial GPD2 Dehydrogenase." International Journal of Molecular Sciences 25, no. 2 (January 12, 2024): 990. http://dx.doi.org/10.3390/ijms25020990.
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‘Inner mitochondrial membrane peptidase 2 like’ (IMMP2L) is a nuclear-encoded mitochondrial peptidase that has been conserved through evolutionary history, as has its target enzyme, ‘mitochondrial glycerol phosphate dehydrogenase 2’ (GPD2). IMMP2L is known to cleave the mitochondrial transit peptide from GPD2 and another nuclear-encoded mitochondrial respiratory-related protein, cytochrome C1 (CYC1). However, it is not known whether IMMP2L peptidase activates or alters the activity or respiratory-related functions of GPD2 or CYC1. Previous investigations found compelling evidence of behavioural change in the Immp2lKD−/− KO mouse, and in this study, EchoMRI analysis found that the organs of the Immp2lKD−/− KO mouse were smaller and that the KO mouse had significantly less lean mass and overall body weight compared with wildtype littermates (p < 0.05). Moreover, all organs analysed from the Immp2lKD−/− KO had lower relative levels of mitochondrial reactive oxygen species (mitoROS). The kidneys of the Immp2lKD−/− KO mouse displayed the greatest decrease in mitoROS levels that were over 50% less compared with wildtype litter mates. Mitochondrial respiration was also lowest in the kidney of the Immp2lKD−/− KO mouse compared with other tissues when using succinate as the respiratory substrate, whereas respiration was similar to the wildtype when glutamate was used as the substrate. When glycerol-3-phosphate (G3P) was used as the substrate for Gpd2, we observed ~20% and ~7% respective decreases in respiration in female and male Immp2lKD−/− KO mice over time. Together, these findings indicate that the respiratory-related functions of mGpd2 and Cyc1 have been compromised to different degrees in different tissues and genders of the Immp2lKD−/− KO mouse. Structural analyses using AlphaFold2-Multimer further predicted that the interaction between Cyc1 and mitochondrial-encoded cytochrome b (Cyb) in Complex III had been altered, as had the homodimeric structure of the mGpd2 enzyme within the inner mitochondrial membrane of the Immp2lKD−/− KO mouse. mGpd2 functions as an integral component of the glycerol phosphate shuttle (GPS), which positively regulates both mitochondrial respiration and glycolysis. Interestingly, we found that nonmitochondrial respiration (NMR) was also dramatically lowered in the Immp2lKD−/− KO mouse. Primary mouse embryonic fibroblast (MEF) cell lines derived from the Immp2lKD−/− KO mouse displayed a ~27% decrease in total respiration, comprising a ~50% decrease in NMR and a ~12% decrease in total mitochondrial respiration, where the latter was consistent with the cumulative decreases in substrate-specific mediated mitochondrial respiration reported here. This study is the first to report the role of Immp2l in enhancing Gpd2 structure and function, mitochondrial respiration, nonmitochondrial respiration, organ size and homeostasis.
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Liu, Shenrong, Yanfen Liao, Zongyuan Zhu, Shushui Wang, Yifan Li, Dongpo Liang, Yumei Xie, and Zhiwei Zhang. "Association between cumulative blood pressure in early adulthood and right ventricular structure and function in middle age: The CARDIA study." Clinical Cardiology 45, no. 1 (January 2022): 83–90. http://dx.doi.org/10.1002/clc.23763.
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Gromova, Ekaterina, Anastasiia Zaremba, and Shimai Su. "Time-Consistency of an Imputation in a Cooperative Hybrid Differential Game." Mathematics 9, no. 15 (August 3, 2021): 1830. http://dx.doi.org/10.3390/math9151830.
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This work is aimed at studying the problem of maintaining the sustainability of a cooperative solution in an n-person hybrid differential game. Specifically, we consider a differential game whose payoff function is discounted with a discounting function that changes its structure with time. We solve the problem of time-inconsistency of the cooperative solution using a so-called imputation distribution procedure, which was adjusted for this general class of differential games. The obtained results are illustrated with a specific example of a differential game with random duration and a hybrid cumulative distribution function (CDF). We completely solved the presented example to demonstrate the application of the developed scheme in detail. All results were obtained in analytical form and illustrated by numerical simulations.
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Bickel, Peter J., Gil Kur, and Boaz Nadler. "Projection pursuit in high dimensions." Proceedings of the National Academy of Sciences 115, no. 37 (August 27, 2018): 9151–56. http://dx.doi.org/10.1073/pnas.1801177115.
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Projection pursuit is a classical exploratory data analysis method to detect interesting low-dimensional structures in multivariate data. Originally, projection pursuit was applied mostly to data of moderately low dimension. Motivated by contemporary applications, we here study its properties in high-dimensional settings. Specifically, we analyze the asymptotic properties of projection pursuit on structureless multivariate Gaussian data with an identity covariance, as both dimension p and sample size n tend to infinity, with p/n→γ∈[0,∞]. Our main results are that (i) if γ=∞, then there exist projections whose corresponding empirical cumulative distribution function can approximate any arbitrary distribution; and (ii) if γ∈(0,∞), not all limiting distributions are possible. However, depending on the value of γ, various non-Gaussian distributions may still be approximated. In contrast, if we restrict to sparse projections, involving only a few of the p variables, then asymptotically all empirical cumulative distribution functions are Gaussian. And (iii) if γ=0, then asymptotically all projections are Gaussian. Some of these results extend to mean-centered sub-Gaussian data and to projections into k dimensions. Hence, in the “small n, large p” setting, unless sparsity is enforced, and regardless of the chosen projection index, projection pursuit may detect an apparent structure that has no statistical significance. Furthermore, our work reveals fundamental limitations on the ability to detect non-Gaussian signals in high-dimensional data, in particular through independent component analysis and related non-Gaussian component analysis.
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Li, Shuping, and Xiaorong Zhao. "Network percolation of the disease transmission based on bipartite networks." International Journal of Modern Physics B 34, no. 06 (February 24, 2020): 2050029. http://dx.doi.org/10.1142/s0217979220500290.
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In this paper, considered heterogeneous infectivity and susceptibility, a general stochastic Susceptible-Infectious-Removed (SIR) epidemic model with the cumulative distribution functions (CDFS) of the infectious contact rate and the infectious period based on bipartite networks is discussed. It is isomorphic to a semidirected random network called the bipartite epidemic percolation network. The epidemic threshold corresponds to the phase transition where a giant strongly connected component appears. It is obtained by using the method of the probability generation function. We show that the critical value of the transmissibility predicted by the bond percolation model is larger than that predicted by the epidemic percolation network. We analyze the influences of the network structure and individual heterogeneity on the epidemic threshold by numerical simulations.
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THIELE, MARK, and WOLF-CHRISTIAN MÜLLER. "Structure and decay of rotating homogeneous turbulence." Journal of Fluid Mechanics 637 (September 21, 2009): 425–42. http://dx.doi.org/10.1017/s002211200999067x.
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Navier–Stokes turbulence subject to solid-body rotation is studied by high-resolution direct numerical simulations (DNS) of freely decaying and stationary flows. Setups characterized by different Rossby numbers are considered. In agreement with experimental results strong rotation is found to lead to anisotropy of the direct nonlinear energy flux, which is attenuated primarily in the direction of the rotation axis. In decaying turbulence the evolution of kinetic energy follows an approximate power law with a distinct dependence of the decay exponent on the rotation frequency. A simple phenomenological relation between exponent and rotation rate reproduces this observation. Stationary turbulence driven by large-scale forcing exhibits k⊥−2-scaling in the rotation-dominated inertial range of the one-dimensional energy spectrum taken perpendicularly to the rotation axis. The self-similar scaling is shown to be the cumulative result of individual spectral contributions which, for low rotation rate, display k⊥−3-scaling near the k∥ = 0 plane. A phenomenology which incorporates the modification of the energy cascade by rotation is proposed. In the observed regime the nonlinear turbulent interactions are strongly influenced by rotation but not suppressed. Longitudinal two-point velocity structure functions taken perpendicularly to the axis of rotation indicate weak intermittency of the k∥ = 0 (2D) component of the flow while the intermittent scaling of k∥ ≠ 0 (3D) fluctuations is well captured by a modified She–Lévêque intermittency model which yields the expression ζp = p/6 + 2(1 − (2/3)p/2) for the structure function scaling exponents.
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ROBUSTOVA, V. V. "THE PROPER NAME MEANING STRUCTURE: INFORMATION VARIATIONS." Linguistics and Intercultural Communication, Issue №1_2023 (September 23, 2023): 85–95. http://dx.doi.org/10.55959/msu-2074-1588-19-26-1-7.
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This article is devoted to the study of the structure of the extralinguistic meaning of a proper name, the layers of information that it includes and the circumstances for their actualization. Onym possesses both linguistic and non-linguistic aspects of meaning, which makes possible the development and dynamics of information represented by the non-linguistic component of meaning. In its structure, archetypal, mythological, religious, scientific, historical, geographical, sociocultural, literary and aesthetic types of information are distinguished, the actualization of which depends both on the context of the use of a proper name and on the background knowledge of the recipient. The existence of several information layers in the structure of the meaning of the onym is analyzed from the standpoint of the theory of spiral development of the meaning of the proper name. The cumulative function of onomastic units and their ability to act as components of cultural memory, representative of the cultural and historical heritage is emphasized. The analysis of the functioning of proper names in a popular science text is illustrated with the examples from the work of Lynne Truss “Eats, Shoots & Leaves”. The interpretive potential of onyms is analyzed, the specifics of dynamics of certain information is singled out in the structure of the meaning of a name in order to achieve the goal of communication both from the point of view of transmitting a certain message, and from the point of view of the expressiveness of the use of linguistic material, which is underlined with the help of the ironic function as realized in it.
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A. Kuzmin, Evgeny. "A study on the problems of the structure of transaction costs." Problems and Perspectives in Management 15, no. 3 (October 31, 2017): 224–33. http://dx.doi.org/10.21511/ppm.15(3-1).2017.06.
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The estimation of transaction costs is a well-known methodological problem, the solution of which determines the possibility, among other things, to estimate the conditions for business operations. The growing complexity of the social and economic interaction emphasizes the special role of transaction costs in regulation of the stability condition. The article analyzes approaches to the determination of the essential characteristics of transaction costs. The scientific evidence of dividing of transaction costs into normal and recertative is provided. Their differentiation is connected to the impact of uncertainty and also the principal unavoidability of transaction costs regardless the efficiency of the economic mechanism and other factors. An important factor here is friction force – flexibility of the economic space. The growth of transaction costs that is observed with the increased uncertainty emphasizes only the revealed features in the friction force of the economic environment. All this led to the conclusion on the availability of a generalizing factor that estimates the conditions of exchange transactions. For this, the notion of transaction capacity was introduced; it expresses the cumulative impact of the external and internal conditions, which, this way or another, are understood by the specialists making the managerial decisions. The existence of some value of transaction costs when transaction is declined presupposes an important assumption that the transaction capacity has the same limits of dynamics. The obtained results allow us to build a function of transaction capacity, which shall be considered as a tool for risk-profile analysis.
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Li, Hongqiu, Jinhui Jiang, Wenxu Cui, Jiamin Zhao, and M. Shadi Mohamed. "One Novel Dynamic-Load Time-Domain-Identification Method Based on Function Principle." Applied Sciences 12, no. 19 (September 25, 2022): 9623. http://dx.doi.org/10.3390/app12199623.
Full textAbstract:
In order to ensure the reliability of the structural design, it is necessary to know the external loads acting on the structure. In this paper, we propose a novel method to identify the dynamic loads based on function principles in the time domain. Assuming the external load remains constant within one micro segment, we establish a linear relationship between external load and structural response in the micro segments based on the mechanical energy conservation law. Next, the external load is obtained by solving the inverse problem in each micro-segment. Finally, the external load in the whole time domain is achieved by fitting the load-identification results in each micro segment. In order to verify the effectiveness and accuracy, single-force and two-force identification, and load identification with noise simulations, are performed on the structures, and the identification results are compared to the ones of the traditional time-domain method with a deviation of less than 5%. The proposed method can effectively solve the problem of cumulative errors in the time-domain method, while its resistance to noise interference is also strong. At last, we verify the experimental performance of the proposed method. The experimental results show the effectiveness and high accuracy of the proposed method. This work presents a first attempt to solve the structural dynamic load with an approach based on a function principle.