Worst In Terms Research Articles

Three-Step Difference Scheme for Solving Nonlinear Time-Evolution Partial Differential Equations

AbstractIn this paper, a special three-step difference scheme is applied to the solution of nonlinear time-evolution equations, whose coefficients are determined according to accuracy constraints, necessary conditions of square conservation, and historical observation information under the linear supposition. As in the linear case, the schemes also have obvious superiority in overall performance in the nonlinear case compared with traditional finite difference schemes, e.g., the leapfrog (LF) scheme and the complete square conservation difference (CSCD) scheme that do not use historical observations in determining their coefficients, and the retrospective time integration (RTI) scheme that does not consider compatibility and square conservation. Ideal numerical experiments using the one-dimensional nonlinear advection equation with an exact solution show that this three-step scheme minimizes its root mean square error (RMSE) during the first 2500 integration steps when no shock waves occur in the exact so...

The transition from college to work during the great recession: employment, financial, and identity challenges

This study examines the challenges that recent college graduates face in a hard-hit US region during the Great Recession. In their poignant and sometimes heartbreaking perceptions of their ‘biggest challenges,’ graduates vividly illustrate the negative implications of degree completion during the recession. Based on an analysis of both closed and open-ended survey data of Michigan's 2012 graduates, we find that women and first generation college graduates fare the worst in terms of their employment status, debt and income levels, and subjective assessments of job opportunities and financial stress. In contrast, men, especially those whose parents have at least a bachelor's degree, were more likely than their counterparts to report that their ‘biggest challenge’ since graduation was linked with making the transition into adult roles. Taken together, these findings suggest widespread difficulty after graduating from college during the Great Recession, and the ways in which these difficulties are linked with gender and class inequalities.

Spatial assessment of the sewage contamination of Kuwait’s marine areas

Discharge of sewage to the coastal areas resulting in the deteriorating quality of seawater and polluted sediments has been one of important stressor in Kuwait. The objective of this study was to conduct spatial assessment of sewage contamination of coastal areas. The assessment was carried out by measuring fecal sterols as indicator of sewage contamination, in the marine sediments collected from 112 locations throughout the Kuwait’s marine areas. The samples were extracted and sterols separated. Derivatized sterols were analyzed by GC/MS in selected ion monitoring mode. The results showed that areas in the vicinity of the sewage outfalls were heavily contaminated. The western part of Kuwait Bay was worst in terms of contamination level. Two off-shore sites in Kuwait Bay were also classified as contaminated. Coprostanol levels in Kuwait Bay ranged from 0 to 39,428ng/g. Southern coastal areas were less severely contaminated.

Produkty strukturyzowane - analiza stóp zwrotu osiągniętych w latach 2000-2013

The aim of this article is to present the structured products market in Poland in the context of gains and losses from completed investments in structured products. It shows when an investment in structured products brought investors profits and when losses. In order to do the analysis, the return rate of gross and net annual rate of return over the period 2000-2013 were assigned to structured products. The rate of return on structured products was compared with inflation and the average annual interest rate of deposits for a period of 12 months. The paper offers a detailed description of the best and the worst in terms of the gross rate of return for structured products on the Polish capital market during the years 2000-2013. The analysis looked at 1800 products available during from early 2000 to the end of 2013.

Application of Flow Methods for Material and Financial Resources Management to Forecast Oil Production in Russia

The paper considers the impact of flow methods on long-term development of oil extracting industry, the impactbeing associated with mineral resources production tax variation. Six oil production scenarios for Russia havebeen considered, comparative analysis of these scenarios is presented. By the end of the calculation period, thescenario that provides for 5% decrease of tax burden closely approximates the scenario of oil production undereffective taxation system In terms of budget receipts volumes. The scenario with mineral resources productiontax rate increase is the worst in terms of oil industry growth leading to the industry collapse. According to thisscenario, an operating company’s tax burden increases to 78%. So far, the world practice has not witnessedeconomic growth under conditions of taxes as high as this; furthermore, taxation history testifies that too hightaxes have not been paid. In terms of oil industry growth, the scenario that provides for 5% decrease of taxburden is the most credible and promising, provided the released flows are invested in production. The samelevel of tax burden decrease (5%) is required to attain oil production levels in Russia in 2018-2020s according tothe 2030 Development Strategy.

The typing performance and preference costs of reducing tactile feedback and tactile landmarks in tablet keyboards

The purpose of this study was to evaluate the effects of tactile landmarks and tactile feedback on keyboard typing under real-world conditions. Four keyboards were tested, representing a range of tactile landmarks versus no landmarks, tactile feedback versus no tactile feedback, and the ability to rest the fingers on the keys vs. keys that triggered when simply touched. Participants completed a typing task on each of the keyboards while their performance and preference was collected. The conventional keyboard with tactile landmarks, tactile feedback, and the ability to rest the fingers was significantly better than the other options both in terms of performance and preference. The capacitive keyboard, which had tactile landmarks but no tactile feedback, nor the ability to rest fingers on the keys without triggering them performed the worst in terms of accuracy and preference, showing that tactile landmarks alone do not ensure good performance.

Characterizing the diurnal patterns of errors in the prediction of evapotranspiration by several land‐surface models: An NACP analysis

AbstractLand‐surface models use different formulations of stomatal conductance and plant hydraulics, and it is unclear which type of model best matches the observed surface‐atmosphere water flux. We use the North American Carbon Program data set of latent heat flux (LE) measurements from 25 sites and predictions from 9 models to evaluate models' ability to resolve subdaily dynamics of transpiration. Despite overall good forecast at the seasonal scale, the models have difficulty resolving the dynamics of intradaily hysteresis. The majority of models tend to underestimate LE in the prenoon hours and overestimate in the evening. We hypothesize that this is a result of unresolved afternoon stomatal closure due to hydrodynamic stresses. Although no model or stomata parameterization was consistently best or worst in terms of ability to predict LE, errors in model‐simulated LE were consistently largest and most variable when soil moisture was moderate and vapor pressure deficit was moderate to limiting. Nearly all models demonstrate a tendency to underestimate the degree of maximum hysteresis which, across all sites studied, is most pronounced during moisture‐limited conditions. These diurnal error patterns are consistent with models' diminished ability to accurately simulate the natural hysteresis of transpiration. We propose that the lack of representation of plant hydrodynamics is, in part, responsible for these error patterns.

Life cycle assessment of alternatives for recycling abroad alkaline batteries from Portugal

The European legislation establishes collection rates and states that all identifiable batteries must undergo treatment and recycling. Due to the inexistence in Portugal of recycling plants for alkaline batteries, those collected there have been sent to Austria and France, and currently, it is pondered to send them to Spain. This study aims to know the potential environmental impacts associated with the management of spent domestic alkaline batteries from collection in continental Portugal to recycling abroad. Three alternative recycling processes are considered: in Austria (A), France (F) and Spain (S). The system in study, from battery collection in continental Portugal to recycling abroad, includes complementary processes necessary for this circuit such as the production of boxes for battery collection and/or transportation and, for easiness of analysis and interpretation, is divided into: (i) container manufacture; (ii) distribution of empty containers; (iii) battery collection and sorting; (iv) international transport for the recycling; and (v) battery recycling. Recovered materials were also quantified. The LCA methodology and the method of impact assessment Eco-indicator 99, Hierarchist version, with two options, with and without inclusion of long-term emissions, were used. This method considers three damage categories: human health, ecosystem quality and resources, which group 11 impact categories. For ecosystem quality, there is a preponderance of the impact of recycling processes F and S regarding all other processes and, in particular, regarding recycling process A. After these, the container production impact is the most significant followed by the transport to Austria. For human health, there is a preponderance of the impact of recycling process S followed by the impact of F, and then of the transport to Austria and, only after, the impact of recycling process A. For resources, process S impact is higher than the one of A and this is higher than system F. The transport shows an expectable impact (highest for Austria, lowest for Spain), but for Austria and for France, it is higher than the impact of the recycling process itself. System F is the most negative in terms of ecosystem quality and S is the worst in terms of human health. In these two damage categories, system A is the best but the worst in the damage category of resources, where F is the best system. If the recovered materials are considered in this balance, the environmental advantage of system A is clear.

Sensitivity of different convective parameterization schemes on tropical cyclone prediction using a mesoscale model

This study presents an intercomparison of four cumulus parameterization schemes (CPS) in the prediction of three cases of tropical cyclones in the north Indian Ocean. The study makes use of the Weather Research and Forecasting model of Non-hydrostatic Mesoscale Model version with a horizontal resolution of 27 km. The four deep cumulus schemes studied are (a) modified Kain–Fritsch (KF), (b) Betts–Miller–Janjic, (c) Simplified Arakawa–Schubert and (d) Grell-Devenyi Ensemble (GD) schemes. Three cases chosen for the study are unique cases with entirely different characteristics, synoptic/convective conditions and with varying levels of performance of the driving global model forecasts. The objective of the current study is to report the relative performance of the CPSs rather than the accuracy of the forecasts, under different convective conditions as reflected in the initial and boundary conditions. The study shows that generally KF scheme produced near-realistic track, intensification and the associated rainfall patterns and GD performed worst in terms of convective organisation and the sustained intensity. The impact of cumulus parameterization schemes and its performance vary widely among the three cases studied. The standard verification scores and the contribution of grid-scale precipitation towards the total rainfall by the mesoscale model are also compared between the different cases as well as the different cumulus parameterization schemes. The performance evaluation of the tropical cyclone predictions by the mesoscale model is influenced by not only the model physics but also the convective conditions as input into the model .

Drought events at different timescales in southern Italy (Calabria)

This study reports an analysis of the spatial drought patterns for a region of southern Italy (Calabria) based on a homogenous monthly precipitation data set of 129 rain gauges for the period 1916–2006. Drought was expressed using the Standardized Precipitation Index (SPI), and drought events were analyzed using both the short-time (3 and 6 months) and the long-time (12 and 24 months) SPI. In particular, in order to characterize the SPI spatial pattern, index data of the three most severe drought events were interpolated and mapped using a geostatistical approach. Results show that these heavy drought episodes have widely affected the Calabria region and the drought that occurred in 2002 was the worst in terms of spatial extent both at short- and long-time scales.

Parking Management Policies and the Effectiveness of Public Policy Solutions

For years, Portuguese public institutions, such as hospitals, offer free parking for employees, patients and visitors. Due to the economic pressure that the country is facing, public institutions are now being pressured to charge for parking. Such measure has been socially contested as free parking has been interpreted as a labor right. However, it is a fact that public institutions cannot keep buying additional areas to supply increasing parking needs. Along this paper, authors evaluate 4 alternative scenarios for parking management, demonstrating that it is possible to do more with fewer resources; there is to say, increase mobility with less consumption of resources. Using a real case study from a hospital area located in Algarve (Portugal), authors will perform an analysis of the effects of four parking management scenarios in terms of traffic and environment pollution. Those results will support the monetary quantification of the environmental externalities costs. The comparative results revealed that scenarios requiring the use of more resources and implying higher public expenditure are worst in terms of traffic, environment and externalities. When parking systems become controlled and restricted, the referring effects worsen, on the immediate term, with additional driving costs for users on the network up to 560 euros/workday, environmental externalities costs up to 102 euros/workday and CO2 emissions increasing up to 4,6kg/workday.

Effect of Wholemeal Durum Wheat Varieties on Bread Quality

In this work the effect of six varieties of durum wheat semolina on the bread physico-chemical and sensorial properties was addressed. In particular, whole grains of durum wheat (Anco Marzio, Claudio, Core, Iride, Saragolla and Cappelli) were finely milled by using an ancient stone milling system. Texture analysis was carried out on both dough and bread samples to evaluate their firmness. Furthermore, tomographic analysis was performed on the bread samples in order to provide a more detailed view of their texture. The Glucose Equivalent, the chemical and the sensory analyses of the bread were also determined. Results highlighted that the lowest Glucose Equivalent valuewas achieved in bread produced with the Anco Marzio cultivar, which appeared instead the worst in terms of texture. Among the investigated samples, bread from the Cappelli variety showed good structural characteristic, a moderate Glucose Equivalent compared to the reference sample (CTRL) and the highest sensory quality.

Multi-step-ahead time series prediction using multiple-output support vector regression

Accurate time series prediction over long future horizons is challenging and of great interest to both practitioners and academics. As a well-known intelligent algorithm, the standard formulation of Support Vector Regression (SVR) could be taken for multi-step-ahead time series prediction, only relying either on iterated strategy or direct strategy. This study proposes a novel multiple-step-ahead time series prediction approach which employs multiple-output support vector regression (M-SVR) with multiple-input multiple-output (MIMO) prediction strategy. In addition, the rank of three leading prediction strategies with SVR is comparatively examined, providing practical implications on the selection of the prediction strategy for multi-step-ahead forecasting while taking SVR as modeling technique. The proposed approach is validated with the simulated and real datasets. The quantitative and comprehensive assessments are performed on the basis of the prediction accuracy and computational cost. The results indicate that (1) the M-SVR using MIMO strategy achieves the best accurate forecasts with accredited computational load, (2) the standard SVR using direct strategy achieves the second best accurate forecasts, but with the most expensive computational cost, and (3) the standard SVR using iterated strategy is the worst in terms of prediction accuracy, but with the least computational cost.

Personal Identity in College and the Work Context: Developmental Trajectories and Psychosocial Functioning

Personal identity formation represents a core developmental challenge for adolescents and young adults. Because much of the identity literature focuses on college students, it is necessary to conduct a detailed inquiry into the ways in which specific commitment and exploration processes develop over time for college students and for employed individuals. Two samples (456 college students and 318 employed individuals) were used to identify identity status trajectories over time and to examine external correlates of these trajectories (i.e. depressive symptoms, self–esteem, identity centrality, community integration, and sense of adulthood). Similar identity trajectories emerged in both college students and employed individuals. Four of these trajectories corresponded to Marcia's identity statuses. In addition, apart from the ‘classical’ or troubled diffusion trajectory, a carefree diffusion trajectory was also obtained. Whereas individuals on an identity–achieved pathway fared best in terms of the outcome measures, individuals in the troubled diffusion trajectory fared worst in terms of self–esteem, depressive symptoms, and community integration over time. Implications and suggestions for future research are discussed. Copyright © 2013 John Wiley & Sons, Ltd.

Impact of Water Quality Parameters on the Clogging of Vertical-Flow Constructed Wetlands Treating Urban Wastewater

In theory, biological and physical clogging, induced as a result of potentially excessive formation of biomass from degradation of pollutants and retention of inert suspended fine particles, respectively, should result in a decrease of treatment performance. However, some wetlands are not prone to clogging in practice. The aim of this study was to compare the impact of different design (aggregate size) and operational (contact time, empty time and chemical oxygen demand [COD] loading) variables on the treatment efficiency and clogging processes. Different vertical-flow constructed wetlands were constructed and operated from June 2011 until June 2012. Data from June 2011 (setting-up period) were not used. The filter with the highest COD loading performed the worst in terms of outflow COD concentration (120 mg/l) but best in terms of COD load reduction (61 %). The wetland with the largest aggregate size had the lowest mean nitrate-nitrogen outflow concentration of 1.2 mg/l. However, the results were similar regardless of aggregate size (10 versus 20 mm) and resting time (24 versus 48 h) for most water quality variables. However, different COD inflow concentrations (COD of 146 mg/l versus COD of 312 mg/l) had a significant (p < 0.05) impact on the treatment performance for COD, ammonia-nitrogen, ortho-phosphate-phosphorus and suspended solids (SS). Serious clogging phenomena impacting negatively on the treatment performance were not observed for any columns. However, a small aggregate diameter, a short contact time, a long resting time and a low COD inflow concentration were most beneficial in reducing SS accumulation within the wetland filters.

Intracorneal Ring Segment in Keratoconus: A Model to Predict Visual Changes Induced by the Surgery

We detected keratoconus cases with a significant potential for poor outcomes following intracorneal ring segment implantation (ICRS). We attempted to predict the potential of a case in terms of gain or loss of corrected distance visual acuity (CDVA). In this retrospective and prospective, consecutive, nonrandomized, multicentric study, 58 keratoconic eyes (aged 1756) were implanted with the keraring using the femtosecond laser technology. The follow-up period was 6 months. keratometric, biomechanical, aberrometric, refractive, and visual variables were measured for two different groups: Group A included eyes that gained 0.2 or more in corrected distance visual acuity (CDVA, decimal scale) and group B included eyes that lost more than 0.15. Correlations between clinical parameters and changes in visual acuity were investigated. In addition, a linear regression model was developed using CDVA, apical keratometry (AK), and a new keratometric parameter defined and named by us as K-factor (K(F)). Significant differences between groups preoperatively were found for CDVA (P = 0.002), AK (P = 0.013), and K(F) (P = 0.025). The following predictive model was obtained using these variables: DeltaCDVA = -0.511 + 0.0007K(F)(p)-0.849CDVA(p)+0.008AK(p).$$ Predictability of the model was 0.797. Sensitivity was 88.1% and specificity 83.3%. The mathematical model predicts that this surgery is very effective in patients with preoperative CDVA (decimal scale) in the range of 0.01 to 0.3, predicting a gain of 3, 4, or even 5 lines. Gains are predicted and confirmed for CDVA between 0.3 and 0.5. For preoperative CDVA between 0.5 and 0.75 visual outcomes are doubtful. Higher values of CDVA often are related to a decrease in CDVA. This model may help surgeons to select the best cases for ICRS implantation and exclude the worst in terms of visual outcomes.

Monitoring progress in the management of hip fractures in South Australia, Australia

The aim of this study was to assess trends in hip fracture rates and outcomes following hospitalisation for hip fracture. Hip fracture admissions increased over the study period. Men fared worst in terms of higher absolute mortality. Refracture rates and male health outcomes require further attention. The aim of this study was to assess trends in hip fracture rates and outcomes following hospitalisation for hip fracture in South Australia (SA). Analysis of routinely collected, linked hospital separations data, of patients admitted to public and private hospitals in SA with a principal diagnosis of femoral neck fracture between July 2002 and June 2008 was done. Main outcome measures include number and rates of hospital admissions, 30-day in-hospital and 1-year mortality following a first hip fracture and subsequent event rates, by age and sex. Unadjusted hip fracture admissions increased in SA from 2002 to 2008 by 20 %, age-standardised (adjusted) admission rates increased overall (+5 %, p = 0.215) and significantly amongst males (+26 %, p = 0.001), while there was no change among women (−1 %, p = 0.763). Within 1 year of a hip fracture, 7 % had broken another bone (5 % had refractured a hip). At 1 year post-fracture, unadjusted mortality was consistently and considerably higher amongst men compared to women (33 versus 19 %, p < 0.001). Age-standardised mortality from admission to 1 year fell but not statistically significantly by 15 % in women (p = 0.131) and 8 % in men (p = 0.510). Women had a reduction in age-standardised in-hospital mortality over time (p = 0.048); there was a non-significant decline in men (p = 0.080). Hip fracture admissions in SA increased over the study period and this appears to be driven by an increase in admissions amongst men. Men fared worst in terms of higher absolute mortality. There is some evidence to suggest refracture rates and male health outcomes require further attention.

Large Scale Probabilistic Drought Characterization Over Europe

A reliable assessment of drought return periods is essential to help decision makers in setting effective drought preparedness and mitigation measures. However, often an inferential approach is unsuitable to model the marginal or joint probability distributions of drought characteristics, such as drought duration and accumulated deficit, due to the relatively limited number of drought events that can be observed in the historical records of the hydrological variables of interest. As an alternative, the marginal and multivariate probability cdf’s of drought characteristics can be derived as functions of the parameters of the cdf of the underlying variable (e.g. precipitation), whose sample series is usually long enough to obtain trustworthy estimates in a statistical sense. In this study, the latter methodology is applied to investigate space-time variability of drought occurrences over Europe by using the CRU TS3.10.01 precipitation dataset for the period 1901–2009. In particular, a methodology able to take into account autocorrelation in the underlying precipitation series is adopted. First, a spatial analysis of historical droughts at European level is carried out. Then, the joint probability distributions of drought duration and accumulated deficit are derived for each cell, with reference to both historical and design drought events. Finally, the corresponding bivariate drought return periods are computed, as the expected values of the interarrival time between consecutive critical droughts.Results show that several heavy drought episodes have widely affected the continent. Among the most recent events, drought occurred during the period 1985–1995 was the worst in terms of extent of the regions characterized by return periods greater than 250 years. Besides Euro-Mediterranean regions, North Western and Central Eastern regions appear more drought prone than the rest of Europe, in terms of low values of return periods.

Shear bond strength of three dual-cured resin cements to dentin analyzed by finite element analysis

ObjectivesTo determine the shear bond strength to bovine dentin of dual-cured resin cements cured in different circumstances, the contraction stress and volumetric shrinkage in both polymerization modes, and to review the failure stress distribution at the cement–tooth interface with finite element analysis. MethodsThe volumetric shrinkage of RelyX Unicem, Panavia F 2.0 and DC Core Automix was determined by mercury dilatometry. Polymerization contraction stress was determined using a constraint tensilometer set-up. For the shear bond strength test, cement discs on bovine root dentin (self-cured and dual-cured), composite discs cemented to dentin (self-cured and dual-cured), and dentin cemented to dentin (self-cured) specimens were fabricated. Specimens were stored in water for 24h (37°C, 100% humidity) and tested (crosshead speed 1mmmin−1). FE modeling of the specimens was carried out in order to calculate the maximum shear stresses in the cement–dentin interface. Differences between groups were determined using two-way ANOVA with Tukey post hoc tests, and paired samples t-tests (α<0.05). ResultsPanavia F2.0 showed significantly lower volumetric shrinkage than the other cements. Dual-curing lead to higher contraction stresses for all tested cements compared to self-curing. RelyX Unicem showed higher volumetric shrinkage when dual-cured. Shear bond strength and maximum shear stress was positively influenced by dual-curing. DC Core Automix performed best and Panavia F2.0 worst in terms of shear bond strength and maximum shear stress. SignificanceCuring mode may play an important role in the final bond strength to dentin of indirect restorations, depending on the material used.

Effects of amplitude modulation on vibrotactile flow displays on piezo-actuated thin touch screen

This paper investigates effects of different amplitude modulation methods of frequency-swept excitation patterns for creating vibrotactile flow displays on a spatiotemporally actuated thin touch screen. Four piezoelectric actuators (bimorph type) located at the midpoints of each side of a screen can be used to make eight directional (horizontal, vertical, diagonal) vibrotactile flows by spatiotemporally actuating two or more piezo-actuators. To determine which amplitude modulation method is the most effective in generating directional vibrotactile flows, an excitation pattern having sweeping frequencies in the range of 50 Hz to 250 Hz with four different time-varying amplitudes are investigated: 1) constant amplitude modulation, 2) linear amplitude modulation (linearly increasing and decreasing amplitude), 3) exponential amplitude modulation (exponentially increasing and decreasing amplitude), and 4) logarithmic amplitude modulation (logarithmically increasing and decreasing amplitude). A user study shows that the exponentially increasing and decreasing the amplitude pattern is the worst in terms of human perception (accuracy, validity, and refinement), while other amplitude modulation methods give similar results. Another user study shows that the eight directional vibrotactile flows can easily be distinguished on the users’ palms. As such, it is expected that these vibrotactile flows can be applied to the user interface design of a mobile device, for example, for identifying callers or giving directions to the elderly and the blind.