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In Europe, the multiplication of elections makes the election calendar a decisive issue given the decreasing participatory trend. Turnout is expected to be higher in simultaneous elections, while it lessens if several elections are held over a short period. The saliency of the preceding ballot may also affect participation in the next one. In this article, we argue that these temporal effects are crucial for European Parliament elections due to their second-order nature. We analyse how the position, frequency and nature of domestic ballots affect European Parliament elections turnout since 1979. Our results indicate that the participation level is less affected by the timing of elections than by their overall frequency. The type of preceding election also matters, although not the second-order nature per se. [ABSTRACT FROM AUTHOR]

Prosocial crowdfunding has achieved a growing audience by providing a financing source for entrepreneurs in the microfinance space. Using data from Kiva, a leading prosocial crowdfunding platform, we examined whether there is a right time to launch a crowdfunding campaign. This is the first study to unravel the role of temporal patterns in securing funds in emerging markets. Our results indicate a reverse turn-of-the-month effect on the fully funded campaigns. We further identified a "positive winter prosocial effect" and a "positive first-half-of-the-week effect" on successful fundraising. As such, our study highlights relevant similarities between financial markets and crowdfunding. [ABSTRACT FROM AUTHOR]

The paper examines dynamic pile test data from 25 high-quality offshore cases, where end-of-initial driving (EoID) and beginning-of-restrike (BoR) instrumented dynamic monitoring was undertaken on tubular piles driven in sands at well-characterised sites after known setup periods. The static resistances derived from signal matching by two independent specialist teams using different software are compared with CPT-based pile capacity calculations, providing the first axial capacity and setup dataset for large offshore piles driven in sand. Complementary re-analyses are made from three onshore/nearshore sites where dynamic and static testing was conducted on comparable piles. Open-ended tubular steel piles with 0.3–3.5 m diameters driven in (mainly dense) sands are all shown to develop marked setup, which is most active over the first 2–10 days. All piles show similar outcomes 20–30 days after installation. However, the larger diameter offshore piles’ dynamic tests indicate no further setup after 30 days, while smaller diameter piles at onshore/nearshore sites continue to display further marked capacity growth. Comparisons of the axial shaft capacities inferred from signal matching with CPT-based design methods provides insights into the performance of the design methods. A trend for long-term pile shaft set-up to decrease with increasing diameter is identified and ascribed principally to the diameter-dependent constrained dilatancy that develops under axial loading at the pile-sand interface.

This paper considers the axial resistances of open-ended, highly instrumented, 763 mm diameter steel pipe piles driven in sands for the EURIPIDES (EURopean Initiative on PIles in DEnse Sands) project at a well-characterized research site at Eemshaven, in the northern Netherlands. It offers new analyses of previously unreported dynamic tests and considers their relationship with four heavily instrumented static compression tests. Rigorous signal matching employing two distinct pile–soil interaction models is reported, supported by careful sensitivity analyses, to interpret the recorded driving signals. The back-calculated shaft resistance profiles show good agreement between the models as well as calculations performed with a global wave equation analysis approach. The study highlights the need to account for the internal soil column resistance. The combined interpretation of the dynamic and static test data indicates a 50% gain in shaft resistance over the 10 days after driving and threefold shaft capacity growth over a total period of 533 days after driving. The outcomes have important implications for driven pile design and field quality monitoring; the case history contributes an important benchmark in the study of long-term set-up trends. [ABSTRACT FROM AUTHOR]

We present a decision support model for patient-centered precision surveillance that assists clinicians and patients for the whole disease prospect to provide a single operational framework of whole type 2 diabetic person care management while introducing experts in the loop modeling that facilitates data collection. Based on real-world data, the scientific computation shall be adopted with experts' experiences for providing the patient health education and accessing complication risks thereby easily delineating disease pathways. A decision tree technique is used to build a single framework consisting of every possible diabetes complication in the decision process. Coping with the complex medical system for the prevention of diabetes and diabetic complications, a patient-centered framework gives the patient interactive, transparent and useful information for better communication in the decision process that includes experts' experience as well as the value of the prediction generated from population-based data. [ABSTRACT FROM AUTHOR]

Photosynthesis is a direct route for carbon sequestration in vegetation, and is influenced by climatic variation (CV) and human activities (HA). Therefore, a quantitative assessment of their influence on vegetation photosynthesis dynamics is pivotal for formulating effective carbon neutrality strategies. Herein, based on the solar-induced chlorophyll fluorescence index (SIF), which reflects the vegetation photosynthesis intensity, and TerraClimate meteorological data, we refined the residual trend approach by incorporating more climatic variables and their time effects on vegetation to assess the influences of CV and HA on SIF dynamics in Southwest China. Our results revealed that an increasing rate of vegetation SIF across Southwest China of 0.0312 Wm−2μm−1sr−1/10a (p < 0.001) from 2000 to 2019, and over 90% of the region exhibited an increase in SIF. The influence of CV on SIF dynamics had time effects, including time-cumulative and time-lag effects. Nevertheless, these effects varied by climatic variables and vegetation types. The variable importance in projection demonstrated that temperature was the primary factor influencing SIF dynamics, followed by precipitation, potential evapotranspiration, downward surface solar radiation, vapor pressure deficit, and wind speed. Furthermore, both CV and HA collectively enhanced the vegetation photosynthesis intensity in the region, HA was the main driver of the SIF increase, contributing 0.0239 Wm−2 μ m−1sr−1/10a, while CV accounted for 0.0073 Wm−2 μ m−1sr−1/10a. Overall, we refined the previous residual trend approach and provided a new way for quantitatively assessing the influences of CV and HA on vegetation photosynthetic intensity. • Vegetation SIF increased significantly in SWC from 2000 to 2019. • The time effects of climatic variables on SIF dynamics vary with vegetation types. • CV and HA jointly contribute to SIF increase, with HA playing a dominant role. [ABSTRACT FROM AUTHOR]

Abstract Above a critical temperature, thermo-thickening associative polymers (TAPs) have a superior ability to decrease the mobility of the water phase, compared to traditional polymers for enhanced oil recovery. The ability to decrease the mobility, will be amplified at low flow velocities, and by the presence of salt, and is much higher in porous media than would be expected from bulk viscosity. In this work, we have examined TAPs ability to reduce the mobility, i.e., to increase the resistance factor. We have studied the effect of increasing the associative content, changing the porous media, changing the salinity, and scaling up the size of the porous media. How the resistance factor evolved, was studied as a function of temperature, velocity, and time. We found that a critical associative content or critical concentration of polymer was needed to achieve thermo-thickening in the porous media. As expected, thermo-thickening increased by increasing the salinity. For the relative homogenous clastic porose media investigated here, ranging from ~ 1Darcy sandstone to multidarcy sand, type of porous media did not seem to have a significant impact on the resistance factor. Time and amount of polymer injected is a critical factor: The buildup of thermo-thickening is delayed compared to the polymer front. For our tests with the weaker systems, we also observed a breakdown of the associative network at very low injection rates, possibly caused by the formation of intramolecular association. Article highlights Key findings from our tests of thermo-thickening associative polymer for enhance oil recovery operations: At high temperature, the polymer solutions mobility in porous media is much lower than expected from viscosity At low temperature, the flow behavior is like that of a traditional synthetic polymer This will mean good injectivity and superior sweep, compared to a traditional polymer for enhanced oil recovery

CO2 phase transition fracturing (CPTF) is considered to be a promising way to improve the recovery efficiency of coalbed methane in deep, tight coal seams. In addition, it is significant to the CO2-ECBM and CO2 storage in coal. To better understand the fracturing radius and time effects of CPTF, a field experimentation was conducted on the Ji-15 coal seam of Pingmei 8th Coal Mine. The results indicate that the fracturing radius and time effects are significantly related; with the increase in fracturing radius, the time for extraction rate to reach the peak value is shorter. The calculated value of effective fracturing radius is 7.56 m via the fitting relationship. According to the CO2 content in different extraction boreholes after fracturing, it can be concluded that the crack zone is 5 m. In addition, the extraction rate of methane firstly increases slowly for a while, and then reaches the peak. This work could provide theoretical directions for the arrangement of fracturing and extraction boreholes in CO2 fracturing works related to CO2-ECBM and gas pre-extraction in coal mining. [ABSTRACT FROM AUTHOR]

Composite steel–concrete slab is a floor typology widely used for building applications. Their design is usually governed by serviceability limit state requirements associated with the time-dependent response of the concrete. In this context, this paper presents a state-of-the-art review of research carried out to date on the long-term behavior of composite steel–concrete slabs. The particularity of this time-dependent response relies on the fact that the concrete cannot dry from the underside of the slab due to the presence of the profiled sheeting while it can dry from its upper surface. In the first part of the paper, a review of the work carried out on the identification of the time-dependent response of the concrete is presented by considering the peculiarities that occur due to the non-symmetric drying condition related to composite slabs. Particular attention is given to shrinkage effects and to the occurrence and influence of the non-uniform shrinkage gradient that develops in this form of construction over time. This is followed by the description and discussion of the experimental work performed on both simply-supported and continuous static configurations of composite slabs. In particular, the work published to date is summarized while highlighting the key parameters of the test samples and of the testing protocols adopted in the experiments. In the last part of the paper, available theoretical and design models proposed for the predictions of the shrinkage-induced behavior of composite slabs are presented and discussed. [ABSTRACT FROM AUTHOR]

Background: In a cross-sectional stepped-wedge cluster randomized trial comparing usual care to a new intervention, treatment allocation and time are correlated by design because participants enrolled early in the trial predominantly receive usual care while those enrolled late in the trial predominantly receive the new intervention. Current guidelines recommend adjustment for time effects when analyzing stepped-wedge cluster randomized trials to remove the confounding bias induced by this correlation. However, adjustment for time effects impacts study power. Within the Frequentist framework, adopting a sample size calculation that includes time effects would ensure the trial having adequate power regardless of the magnitude of the effect of time on the outcome. But if in fact time effects were negligible, this would overestimate the required sample size and could lead to the trial being deemed infeasible due to cost or unavailability of the required numbers of clusters or participants. In this study, we explore the use of prior information on time effects to potentially reduce the required sample size of the trial. Methods: We applied a Bayesian approach to incorporate the prior information on the time effects into cluster-level statistical models (for continuous, binary, or count outcomes) for the stepped-wedge cluster randomized trial. We conducted simulations to illustrate how the bias in the intervention effect estimate and the trial power vary as a function of the prior precision and the mis-specification of the prior means of the time effects in an example scenario. Results: When a nearly flat prior for the time effects was used, the power or sample size calculated using the Bayesian approach matched the result obtained using the Frequentist approach with time effects included. When a highly precise prior for the time effects (with accurately specified prior means) was used, the Bayesian result matched the Frequentist result obtained with time effects excluded. When the prior means of the time effects were nearly correctly specified, including this information improved the efficiency of the trial with little bias introduced into the intervention effect estimate. When the prior means of the time effects were greatly mis-specified and a precise prior was used, this bias was substantial. Conclusion: Including prior information on time effects using a Bayesian approach may substantially reduce the required sample size. When the prior can be justified, results from applying this approach could support the conduct of a trial, which would be deemed infeasible if based on the larger sample size obtained using a Frequentist calculation. Caution is warranted as biased intervention effect estimates may arise when the prior distribution for the time effects is concentrated far from their true values. [ABSTRACT FROM AUTHOR]

The objective of this study is to establish a causal relationship between the Mediterranean diet (MD) and various measures of overweightness using the Croatian Adult Health Survey 2003 data. Our results show that among three measures of obesity (body mass index, waist-to-hip ratio (WHR) and obesity (BMI ≥ 30), we found statistically the most convincing relationship between the BMI and the MD. Our results show that an increase in the Mediterranean diet aggregate index by 10% reduces the BMI by about 0.9%. When the MD10 index is replaced with the set of its ten constituent food groups, as a group, these food variables are jointly statistically significant, most of them have expected (negative) signs, and some of them are also individually significant. For the other two overweight measurements (WHR and obesity) we found that the impact of MD aggregate index is insignificant but when the index is replaced by its ten constituent food elements, these are jointly statistically significant in explaining the variation in the obesity measures.

This experimental study is dedicated to the measurements of gas permeability under confinement and to preliminary characterizations of salt rock poromechanical behavior. Salt porosity and permeability under loading are recorded either with argon or hydrogen gas. Permeability measurements carried out with both gases led to similar values. Poromechanical effects occur but they are weak and strongly dependent on the level of confining pressure. Furthermore, triaxial tests have been used to investigate the evolution of permeability of damaged salt samples with time and confinement. These experimental characterizations are finally analysed in the context of gas storage applications. [ABSTRACT FROM AUTHOR]

Composite steel–concrete slab is a floor typology widely used for building applications. Their design is usually governed by serviceability limit state requirements associated with the time-dependent response of the concrete. In this context, this paper presents a state-of-the-art review of research carried out to date on the long-term behavior of composite steel–concrete slabs. The particularity of this time-dependent response relies on the fact that the concrete cannot dry from the underside of the slab due to the presence of the profiled sheeting while it can dry from its upper surface. In the first part of the paper, a review of the work carried out on the identification of the time-dependent response of the concrete is presented by considering the peculiarities that occur due to the non-symmetric drying condition related to composite slabs. Particular attention is given to shrinkage effects and to the occurrence and influence of the non-uniform shrinkage gradient that develops in this form of construction over time. This is followed by the description and discussion of the experimental work performed on both simply-supported and continuous static configurations of composite slabs. In particular, the work published to date is summarized while highlighting the key parameters of the test samples and of the testing protocols adopted in the experiments. In the last part of the paper, available theoretical and design models proposed for the predictions of the shrinkage-induced behavior of composite slabs are presented and discussed.

Highlights • Environmental amenities show heterogeneous capitalisation patterns across housing submarkets and time. • Volcanic parks and beaches may lead either to discounts or premiums across the price distribution. • Households incur a trade-off between ecosystem services of open spaces and regulations on development. • Outcome of trade-off depends on the submarket we focus. Abstract The value of environmental amenities has been studied for decades in the hedonic housing prices literature. Numerous studies have found that amenities such as marine, river and woodland habitats, national and regional reserves, urban parks, or wetlands contribute positively on the formation of housing prices. Work is scarce when considering heterogeneity across submarkets and time. Auckland, New Zealand's largest city, has a unique landscape with open spaces, waterways, coastal areas and volcanic features. Local housing market is highly segmented and the city has gone through a bust, recovery and boom cycle in the last decade. This paper incorporates heterogeneity across submarkets and time, and examines how they affect the capitalisation of amenities into housing prices. We construct a dataset of about 280 thousand sale transactions between 2000 and 2016 in Auckland and estimate hedonic models based on unconditional quantile regressions. We find diverse capitalisation patterns across housing submarkets. Beaches may add price premiums of 5.1% in houses in the upper-end of the distribution, but also price discounts of 2.1% in houses in the lower-end of the distribution. We use a detailed categorisation of parks and find that volcanic parks may add premiums for houses in the 70% percentile and above of the price distribution, but also imply price discounts values for houses around the median price and below. We argue that the differing effects occur because of trade-offs between regulations to protect amenities and the ecosystem services they provide, conditional to specifics of the location of houses. [ABSTRACT FROM AUTHOR]

The paper examines dynamic pile test data from 25 high-quality offshore cases, where end-of-initial driving (EoID) and beginning-of-restrike (BoR) instrumented dynamic monitoring was undertaken on tubular piles driven in sands at well-characterised sites after known setup periods. The static resistances derived from signal matching by two independent specialist teams using different software are compared with CPT-based pile capacity calculations, providing the first axial capacity and setup dataset for large offshore piles driven in sand. Complementary re-analyses are made from three onshore/nearshore sites where dynamic and static testing was conducted on comparable piles. Open-ended tubular steel piles with 0.3–3.5 m diameters driven in (mainly dense) sands are all shown to develop marked setup, which is most active over the first 2–10 days. All piles show similar outcomes 20–30 days after installation. However, the larger diameter offshore piles' dynamic tests indicate no further setup after 30 days, while smaller diameter piles at onshore/nearshore sites continue to display further marked capacity growth. Comparisons of the axial shaft capacities inferred from signal matching with CPT-based design methods provides insights into the performance of the design methods. A trend for long-term pile shaft set-up to decrease with increasing diameter is identified and ascribed principally to the diameter-dependent constrained dilatancy that develops under axial loading at the pile-sand interface. [ABSTRACT FROM AUTHOR]

Highlights • Creep tests on RACFST with recycled aggregates obtained from different parent waste material. • Creep model for RACFST accounting for the influence of the strength of the parent concrete. • Influence of the strength of the parent waste concrete on the creep behaviour of the RACFST columns. Abstract This paper intends to investigate how the creep behaviour of recycled aggregate concrete filled steel tubes (RACFST) is affected by the strength of the parent waste concrete that used to produce the recycled coarse aggregates (RCAs). Long-term tests were performed on ten RACFST members. A creep model was suggested to account for the influence of the strength of the parent waste concrete. Based on an extensive parametric study, it was found that with the strength of the parent waste concrete varying between 35 MPa and 70 MPa, a maximum of 37% difference can be achieved in the long-term deformations of the RACFST members. [ABSTRACT FROM AUTHOR]

The behavior of pile composite foundation is studied using the flexibility method. During the analysis, determination of the flexibility matrix (settlement) is critical. However, conventional methods of Winkler and elastic half-space foundation models are incapable of considering the time effects of soil consolidation and creep. The foundation model of Zaretsky and Tsytovich [1965] can be used to evaluate settlement for unsaturated soils, but the complexity of numerical integration over an arbitrary loading area hinders its application. In this paper, a novel scheme is proposed for numerical integration by rotating the loading surface using the equiareal transformation technique. Therefore, a simplified closed-form solution is developed to calculate time dependent settlement for foundation soils. The efficacy of the proposed technique is demonstrated using illustrative examples of an elastic half-space, a rigid raft foundation without piles, and rigid pile composite foundations with multiple piles under surface loading. Furthermore, parametric study is conducted to evaluate the sensitivity of model parameters. The permeability k and Poisson's ratio ν are found to be important, whereas pore pressure coefficient β and degree of saturation B are less significant in the calculation. [ABSTRACT FROM AUTHOR]

We develop a theoretical model of ex post doping audits and analyze their effects on an athlete’s doping decision. In our model, the doping agency can store doping samples and retest them at a later point. We show that there is a doping minimizing storage and retesting mix for the doping agency and that storing doping samples will reduce the athletes’ doping intensity. Furthermore, there is a threshold for the agency’s antidoping budget. If the budget exceeds this threshold, inefficiencies in the antidoping battle will occur and, depending on the agency’s objective, the athletes’ doping incentives may even increase. [ABSTRACT FROM AUTHOR]

Concrete-filled steel tubes (CFST) are becoming a popular structural solution for arch bridges because of their high compressive strength and efficiency in construction. For long span CFST arch bridges, the time-dependent behaviour of the core concrete may affect the stability of CFST arches. Despite this, only limited research has been carried out to date on their creep buckling behaviour. In this context, this study aims to investigate the influence of the prebuckling deformation induced by time effects on the out-of-plane stability of single parabolic CFST arches with fixed ends and subjected to uniformly distributed loads applied along the span by means of the finite element method using ABAQUS. The time-dependent behaviour of the concrete has been described using the Eurocode 2 model and implemented in the analysis using the integral type creep law. The nonlinear material property and the confinement effects under ultimate condition have also been taken into account and implemented in ABAQUS with UMAT subroutines. The accuracy of the proposed analysis method has been validated against the experimental results of an out-of-plane buckling test of a 1:10 scaled CFST arch reported in the literature. An extensive parametric study has been then carried out and it has been found that the ultimate capacity of the arches can be decreased by up to 18% due to the prebuckling deformation induced by time effects. Finally, designing equations are proposed based on the finite element analysis results to predict the ultimate loads of CFST arches accounting for time effects. [ABSTRACT FROM AUTHOR]

During the excavation process of the underground powerhouse caverns at the Houziyan Hydropower Station, some failure phenomena (including split, spalling, ballooning and cracking of the shotcrete layer) occurred and posed a great threat to the safety of the structure, construction equipment and people's lives. Monitoring data show that the surrounding rock mass deformation at several locations (more than 17% of the total monitoring points) is larger than 50 mm after the sixth step of excavation, which is beyond the average deformation of completed underground main powerhouse caverns under similar scale and in-situ stress conditions in China. The field investigations, monitoring data and numerical simulations indicate that high second principal stress with a direction sub-vertical to the axis of the main powerhouse has a remarkable effect on the deformation and failure of the underground powerhouse. The failure types along the depth of the high sidewall at the main powerhouse can be identified as peeling off at the surface and slabbing and spalling at the near surface and deeper tension fracture failure. The failure at the high sidewall of the main powerhouse has obvious time effects. Expanding the deep fractures, tension and sliding of weak structural planes is highly correlated with the increase of the deformations, and the high second principal stress leads to an increase of the dynamic unloading effects and unloading relaxation degree, which lead to a higher occurrence of crack expansion and deep fractures. Meanwhile, the relatively high second principal stress exacerbated the stress concentration at the upstream spandrel and downstream arch foot of the main powerhouse and led to serious ballooning and cracking of the shotcrete layer and split failure of the surrounding rock mass. [ABSTRACT FROM AUTHOR]

In this paper, multidimensional credibility model with a type of dependence structures over risks and over time is considered. By means of the projection method, the inhomogeneous and homogeneous Bühlmann credibility estimators are obtained, which are extended to slightly more general versions. The inhomogeneous estimator can be expressed as the weighted sum of individual mean, overall sample mean and collective mean. In addition, the estimations of structural parameters are also investigated. [ABSTRACT FROM AUTHOR]

1. Ants are a ubiquitous and crucial component of Australian Eucalyptus forests, but responses to long-term habitat fragmentation remain poorly understood. Two ant species were followed across a 21-year history of pine plantation establishment and maturation in a southeast Australian Eucalyptus forest. 2. At Wog Wog in southeastern Australia, a Native Eucalyptus forest was clear-cut to make way for plantation establishment and 12 remnant patches of forest were left intact and subsequently surrounded by a pine matrix. Pitfall traps were placed in the continuous native forest, remnant Eucalyptus patches, and the pine matrix between fragments, and were stratified based on proximity to remnant patch edges and habitat type. Two ant species are focused on that represent the only remaining data for the early years of the experiment. 3. While Leptomyrmex erythrocephalus ( Fabricius), the rarer of the two species, was not affected by fragmentation in the short term, 21 years after fragmentation, it was less likely to occur in both the mature pine matrix and fragments than in continuous forest controls. Aphaenogaster longiceps ( Smith F.) was equally likely to occur in the fragments, continuous forest, and pine matrix early in the experiment but by year 21 post-fragmentation was less likely to occur in the pine matrix than fragments or controls. 4. Importantly, we only detected negative impacts of fragmentation on ant occurrence as the pine plantation matrix matured and isolated ant populations on fragments. 5. It is concluded that changes in matrix suitability and specific habitat characteristics influence ant persistence in Eucalyptus fragments. [ABSTRACT FROM AUTHOR]

This study presents a scaling analysis of the time development of clear-water scour depth at bridge piers. It shows that the widely-used exponential formula can be theoretically derived with scaling arguments. The derivation provides connections between the physical pier-scouring process and two empirical constants used in the formula. The dependence of the two constants on sediment coarseness is calibrated using published laboratory data with scour duration ranging from 49 to 1094 h. The analysis presented is restricted to conditions, including steady flow, clear-water scour, narrow circular cylindrical pier, and uniform sediment with low coarseness. [ABSTRACT FROM AUTHOR]

Encasing recycled aggregate concrete (RAC) inside steel tubes provides a solution to use RAC in vertical-load bearing members. Such composite members are referred to as recycled aggregate concrete filled steel tubular (RACFST) columns. Previous researches have focused on RACFST elements with concrete strength of 30 MPa. This paper intends to provide new experimental data for the benchmarking of numerical models using RAC with compressive strength of 50 MPa. Twenty-one RACFST specimens with different aggregate replacement ratios were prepared for the tests. The adequacy of using available RAC concrete models to predict the long-term responses of the RACFST specimens was evaluated based on the experimental results. Parametric study was then carried out to evaluate the long-term responses of RACFST members during their whole service life. The accuracy of different algebraic methods that suitable for design calculations was investigated based on the results obtained using the step-by-step procedure. Finally, a finite element model was developed with ABAQUS, which has been validated against measurements of long-term tests on slender RACFST columns. Investigation shows that the incorporation of recycled aggregates can increase the long-term deformation of composite columns by up to 40%. By considering a nil exposed perimeter, the available amplification factors proposed for RAC members can be directly introduced to the Eurocode 2 to well predict the long-term responses of RACFST specimens. The Mean Stress method was recommended for simple design calculations. [ABSTRACT FROM AUTHOR]

This paper presents a mixed finite element (FE) model for the nonlinear time-dependent analysis of composite beams with partial shear connection. The key idea is to consider, as a first approach, a viscoelastic/plastic model for the concrete slab in order to simulate the interaction between the time effects of concrete, such as creep and shrinkage, and the concrete cracking. Creep is taken into account via linear aging viscoelasticity, while cracking is modeled using an elastoplastic model with softening. A nonlinear isotropic/kinematic hardening model is adopted for steel behavior and an appropriate nonlinear constitutive relationship is utilized for the shear stud. A consistent time integration is performed by adopting the Euler backward scheme. Finally, comparisons between the numerical results and experimental data available in the literature are undertaken to validate the accuracy of the model. It is shown that the interaction between cracking and time effects (creep and shrinkage) significantly increases the deflection. [ABSTRACT FROM AUTHOR]

Food sensory tests generally require panelists to abstain from food or beverage consumption 30 min to an hour before a tasting session. However, investigators do not have a complete control over panelists' intentional or unintentional consumption prior to a tasting session. Currently, it is unclear how prior consumption impacts the results of the tasting session. The aim of this study was to determine the effects of temporary and lingering mouth irritation caused by the consumption of coffee, orange juice, and gum within 1, 15, or 30 min prior to the tasting session on the perception of 4 basic tastes: sweet, salty, sour, and bitter. Fifty-two panelists were served a beverage (orange juice, coffee, and water) or were asked to chew a piece of gum, and then, remained in the waiting room for 1, 15, or 30 min. They were then asked to report taste intensities using 15-cm unstructured line scales. Mean intensities of all tastes were not significantly different when orange juice was a primer at 1, 15, and 30 min when compared to water. Mean intensities of bitter were significantly lower when coffee was a primer at 1, 15, and 30 min than when water was a primer. Mean intensities of sweet were significantly lower when gum was a primer at 1 and 15 min than when water was a primer. The findings showed that it is necessary for 30 min or more waiting period of no food or beverage consumption prior to sensory testing. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, a number of fundamental concepts are presented and explained. These include (1) differences among an instant compression line, a normal consolidation line, and a true instant compression line; (2) the uniqueness of viscoplastic strain rates with a stress-strain state; (3) whether the creep compression is smaller than the instant compression; (4) the separation of the total strain rates; (5) the relation between elastic-plastic models and elastic viscoplastic (EVP) models, etc. The major conclusions are the following: (1) the elastic compression is the true instant compression; (2) the magnitude of a creep-strain rate at a stress-strain state point is unique, independent of the loading path to reach this point; (3) the true instant (elastic) compression is much smaller than the creep compression; (4) it is more appropriate that strain rates of geomaterials are composed of elastic strain rates and viscoplastic strain rates; (5) the onedimensional (1D) EVP (1D EVP) is a genuine extension of Maxwell's linear rheological model for considering the nonlinear behavior of soils; (6) the EVP model is more general than an elastic-plastic model; (7) the nonlinear functions proposed by the author are good for fitting the creep compression and the compression under high stress of most soft soils in 1D straining; and (8) the three-dimensional EVP model is rigorously derived using the 1D EVP model approach and the modified Cam-Clay model, but further improvements of this model are still needed. At the end, a number of areas are presented for further study. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article proposes asymptotically unbiased estimators of autocovariances and autocorrelations for panel data with both individual and time effects. We show that the conventional autocovariance estimators suffer from the bias caused by the elimination of individual and time effects. The bias related to individual effects is proportional to the long-run variance, and it related to time effects is proportional to the value of the estimated autocovariance. For the conventional autocorrelation estimators, the elimination of time effects does not cause a bias while the elimination of individual effects does. We develop methods to estimate the long-run variance and propose bias-corrected estimators based on the proposed long-run variance estimator. We also consider the half-panel jackknife estimation for bias correction. The theoretical results are given by employing double asymptotics under which both the number of observations and the length of the time series tend to infinity. Monte Carlo simulations show that the asymptotic theory provides a good approximation to the actual bias and that the proposed bias-correction methods work well. [ABSTRACT FROM AUTHOR]

It is examined whether the relationship J ∝ A/ r, and the subsequent coauthor (CA) core notion (Ausloos, Scientometrics 95(3):895-909, ), between the number ( J) of joint publications (JPs) by a 'main scientist' [leading investigator (LI)] with her/his CAs can be extended to a team-like system. This is done by considering that each CA can be so strongly tied to the LI that they are forming binary scientific star (BSS) systems with respect to their other collaborators. Moreover, publications in peer review journals and in 'proceedings', both often thought to be of 'different quality', are separately distinguished. The role of a time interval for measuring J and α is also examined. New indirect measures are also introduced. For making the point, two LI cases with numerous CAs are studied. It is found that only a few BSS need to be usefully examined. The exponent α turns out to be 'second scientist' weakly dependent, but still 'size' and 'publication type' dependent, according to the number of CAs or JP. The CA core value is found to be (CA or JP) size and publication type dependent, but remains in an understandable range. Somewhat unexpectedly, no special qualitative difference on the BSS CA core value is found between publications in peer review journals and in proceedings. In conclusion, some remark is made on partner cooperation in BSS teams. It is suggested that such measures can serve as criteria for distinguishing the role of scientists in a team. [ABSTRACT FROM AUTHOR]

Concrete-filled steel tubular (CFST) arch bridges have gained popularity over the last decades for use in long-span applications. At service conditions, these bridges are influenced significantly by the time-dependent behavior of the concrete. This paper presents a finite-element model that was developed using commercial finite-element software and is capable of describing the time-dependent behavior. The proposed approach can account for the construction process, time effects, and geometric nonlinearity. The time-dependent behavior of the core concrete in the arch ribs was modeled using European guidelines and the integral-type creep law, implemented with the finite-element model with a user-defined subroutine. The accuracy of the proposed method was validated against real site measurements recorded for a representative arch bridge. As part of this work, the necessity of considering the variation of the time of first loading and the geometric nonlinearity has been discussed. Finally, a simplified method was developed based on the results of the refined finite-element model and is recommended for possible use in day-to-day routine design. [ABSTRACT FROM AUTHOR]

We performed systematic current-voltage measurements ( I- V curves) in Ag-added the polycrystalline YBaCuO sample (YBCO/Ag) as a function of the transport current ( I), temperature ( T), external magnetic field ( H), and sweeping rates (d I/d t). Standard and reverse procedures were used in the measurements of I- V curves. The obtained results were compared to I- V curves of the YBCO and polycrystalline sample of MgB. Upon cycling transport current, the I- V curves of the YBCO/Ag sample exhibit hysteresis effects for both procedures and are sensitive to the variation of d I/d t. The experimental data reveal that the irreversibilities in the I- V curves of YBCO are more prominent than those of YBCO/Ag. Furthermore, there are no considerable hysteresis effects in the I- V curve of MgB and this behavior is attributed to the absence of the weak-link structure in MgB. We suggest that the physical origin of the rather small hysteresis effects in the I- V curves of the YBCO/Ag sample can be related to the destruction of weak-link structure due to the addition of Ag into the superconducting matrix. Ag destroys partly the intergranular pinning properties of the YBCO ceramic by increasing grain coupling and, therefore, the irreversibilities in the I- V curves of the YBCO/Ag decrease considerably. The instabilities and short- and long-lived plateau regions observed in I- V curves were explained in terms of plastic flow of flux lines along easy motion channels, which are considered mainly as metallic silver paths in the YBCO/Ag sample. At moderate dissipation levels, we could not observe any difference between the data obtained by using the standard and reverse procedures. This suggests that the surface effects are also weakened by the addition of Ag into the superconducting structure. [ABSTRACT FROM AUTHOR]