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Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) 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.)

Ductile-to-brittle transition (DBT) characteristics of three steels for reactor pressure vessel (RPV) belt line application are analyzed from new parameters based on model functions describing the strength and toughness characteristics of the materials. In order to estimate nil-ductility temperature (NDT) from strength property, a strain rate-compensated temperature parameter based on the thermally activated deformation of materials is adopted. A measure of NDT is determined from tensile strength properties for the first time assuming an estimated notch tip strain rate at the lower shelf. It is estimated to be 110, 42, and 106 K for the Cr-Mo-V-Ni, 20MnMoNi55, and A533B steels, respectively. The measure of ductile-to-brittle transition temperature (DBTT) in steels using 41-J Charpy impact-absorbed energy on the basis of a logistic class of functions is compared and shown to be equivalent with those obtained from fitting the tanh model equation. A bi-logistic function based on the concept of separable parameters representing the fracture of ductile and brittle zones in steels within the DBTT regime was applied to model the Charpy impact energy behavior of the three steels. The bi-logistic function-fitting parameters yielded a new measure of brittleness as a DBT characteristic of steels that correlated well with other measures of transition temperature of the selected RPV steels. The parameters from the hyperbolic and logistic fitting were used to develop a model relationship suitable for the generation of a master curve based on Charpy energy in exponential form that unifies the transition temperature behavior of the selected western and eastern RPV materials. The model relationship is also found to closely predict ~5 K of the reference temperature To determined as per American Society for Testing and Materials standard E1921 of the selected RPV steels. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Polonorum. Agricultura is the property of University of Technology & Life Sciences 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.)

Abstract The logistic function is used to forecast energy consumed worldwide and oil production in the U.S. The logistic substitution model is used to describe the energy mix since 1965 presenting a picture significantly different from the one covering the previous 100 years. In the new picture coal gently gains on oil and hydroelectric gains on natural gas even if it is three times smaller. Finally, renewables—wind, geothermal, solar, biomass, and waste—grow exclusively on the expense of nuclear, and are poised to overtake it by the late 2030s. By mid-21st century, coal, oil, and natural gas still remain the main players of comparable size. Hydroelectric has almost doubled in size. The only significant substitution is that of renewables having replaced nuclear albeit remaining at less than a ¼ the size of the other three energy sources. U.S. oil produced by fracking is forecasted to cease by mid-21st century, while oil produced by traditional methods should continue on its slowly declining trend. US oil production is likely to represent less than 1% of the oil consumed worldwide by mid-21st century. Highlights • By mid-21st century coal, oil, and natural gas will be the major energies comparable in size; hydroelectric will double. • By mid-21st century renewables will have practically replaced nuclear energy but still at ¼ the size of the other energies. • US oil production has followed a logistic trajectory extremely closely for 100 years. • US oil production by fracking is 30% completed through its logistic trajectory. • US oil production will represent less than 1% of the oil consumed worldwide by mid-21st century. [ABSTRACT FROM AUTHOR]

Abstract A combination of Logistic and Monod functions was proposed in this paper to study Microcystis aeruginosa growth in incubator experiments. This enables the Microcystis aeruginosa growth dynamics to be better described in incubator experiments and its parameters to be calculated more accurately. This method was justified by the data from the experiment and applied to study the effect of prometryn on Microcystis aeruginosa growth. In the experiment, a different concentrations of prometryn (0, 50, 100 and 200 μg·L−1) were added to the culture medium; the algal cell density, concentrations of orthophosphate (PO 4 3−-P) and ammonia nitrogen (NH 4 +-N) were measured. The results show that Microcystis aeruginosa growth with time can be well described using the Logistic function. The maximum algae densities of Microcystis aeruginosa corresponding to the four prometryn concentrations are 11.7 × 106, 8.1 × 106, 5.6 × 106 and 3.0 × 106 cells·mL−1, respectively. The derived formula for the specific growth rate, growth rate and inhibition rate using Logistic function agreed reasonably well with the measured data. It was found that variations of consumed nutrients concentrations (PO 4 3−-P and NH 4 +-N) can also be well described by the Logistic function. A function that describes the relationship between algal densities and consumed nutrient (PO 4 3−-P and NH 4 +-N) concentrations is also derived from the Logistic function. Combination of Monod and Logistic functions can better describe relationship between specific growth rates and nutrients concentrations compared to the use of Monod function alone. In general, the half saturation coefficient, K c for PO 4 3−-P (4.74 × 10−4, 1.99 × 10−3, 5.54 × 10−3 and 3.87 × 10−2 mg·L−1) and K c for NH 4 +-N (1.80 × 10−3, 5.84 × 10−3, 5.23 × 10−3 and 1.06 × 10−2 mg·L−1) in Monod function increase with increasing prometryn concentrations, which indicates that the affinity of algae growth to PO 4 3−-P and NH 4 +-N decrease with increasing prometryn concentrations. In addition, relationships between nutrients concentrations and time can be derived by combining of Monod and Logistic functions, which agree well with the measured data. It is concluded that the combined application of Monod and Logistic functions provides a promising and more robust method of studying algal growth in incubator experiments. Highlights • Combination of Monod and Logistic functions describe relationship between specific growth rates and nutrients concentrations • Observed shifts of limiting nutrients by prometryn • Developed equations for critical times to demarcate algal growth phases • Logistic function could describe kinetics of consumed nutrients concentrations [ABSTRACT FROM AUTHOR]

Predicting the pattern of clothing adjustment to climate change can provide important basis for thermal comfort and energy consumption analysis. This study proposed a clothing model (IC-RM model) to predict indoor clothing insulation based on people's thermal history. In the IC-RM model, the running mean (RM) outdoor temperature (exponentially weighted running mean of the past outdoor temperatures) was used as the outdoor climate index to reflect the thermal history. Different from the existing models, the IC-RM model adopted a four parameters logistic function to fit the relation between indoor clothing insulation and the RM outdoor temperature. A longitudinal thermal comfort survey (13 months) was conducted in two different types of naturally ventilated building in Changsha China. The decreased freedom of clothing adjustment at high/low outdoor temperatures and notable effects of the past outdoor temperatures on the indoor clothing insulation were observed. The IC-RM model was implemented using 1427 useful clothing records collected during the survey. The high R 2 value (>0.9) for the IC-RM model indicated that the proposed model provides an effective method to quantify the change of indoor clothing insulation based on the effect of thermal history. Compared with linear, exponential and power functions, the logistic function exhibited better performance in quantifying the tendency for the variation in the indoor clothing insulation with the RM outdoor temperature. [ABSTRACT FROM AUTHOR]

The paper studies how the stress state of the interface between structural elements in a block-structured medium affects its deformation response to dynamic loading. It is shown that the normalized shear stress and mean stress are the major factors that determine the deformation response of the interface. We propose to describe the dependence of the value of induced irreversible displacement at the interface on the normalized shear stress using a logistic function. The central point of this function is the point of transition from the quasi-elastic to quasi-plastic stage of the interface shear deformation. The obtained empirical dependences are important for understanding the mechanism of irreversible strain accumulation in fault zone fragments and, particularly, for the development of an earlier proposed approach to estimate the characteristic level of active shear stresses in separate tectonic fault regions. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology 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 a 3-part series of papers, of which this paper is Part II, we investigate the applicability of the fully quadratic hexa-27 element (see Part I) to four problems of interest to the pressure vessels and piping community: (1) The solid-element-based analysis of a welded pipe elbow with a longitudinal surface crack in one of its weldments. (2) The solid-element-based analysis of the elastic bending of a simple cantilever beam, of which the exact solution is known. (3) The tetra-04 element-based analysis of the deformation of a wrench. (4) The shell-element-based analysis of a barrel vault. In this paper, we develop a two-step method first to estimate the uncertainty of a converging series of finite-element-mesh-density-parametric solutions using a 4-parameter logistic function, and then to extrapolate the results of a specific quantity (e.g., a stress component) to an extremely fine mesh density approaching the infinite degrees of freedom. The estimated parameter of the upper bound of the logistic function serves as the “best” estimate of the chosen quantity such as a specific stress component. Using a super-parametric approach, as described in Part III of this series, we show that the hexa-27 element is superior to tetra-04, hexa-08, and hexa-20. [ABSTRACT FROM AUTHOR]

In order to facilely predict the multicomponent breakthrough curves and avoid the complicated numerical solution, this work proposes two empirical models based on the logistic and Gompertz functions. The S-shaped and bell-like curves correspond to the adsorption and displacement processes respectively. The equilibrium loading of each component can be calculated by integration of the measured breakthrough curves. The effects of the model parameters on the breakthrough curves are investigated. The applicability of the two empirical models is validated by three binary and four ternary adsorption systems, including the gas–solid and liquid–solid adsorption. The residual plot and coefficient of determination (R 2) are used to evaluate their fitting quality. The results indicate that the fitting curves agree well with the experimental data and all of the residuals are distributed randomly. The five model parameters (k , τ , k *, τ * and c) are easily obtained by the nonlinear regression. For example, the fitting results are k = 1.37 × 10−2 min−1, τ = 292 min, k * = 1.25 × 10−2 min−1, τ * = 453 min and c = 85.3 for adsorption of n -butyl acetate and p -xylene on granular activated carbon. On the whole, the Gompertz model is superior to the logistic model in terms of the fitting accuracy. The significance of this work is to provide a simple and practical method for prediction of the multicomponent breakthrough curves. [ABSTRACT FROM AUTHOR]

In view of the fact that the follow-up search for an optimal topology is affected by deleting a large number of high-relative-density elements. When the typical density interpolation approach, namely, solid isotropic microstructures with penalization (SIMP), is employed in the continuum structural topology optimization, a new density interpolation approach based on the logistic function is proposed in this paper. This method can weaken low-relative-density elements while enhancing high-relative-density elements by polarization, and then rationally realize polarization of the intermediate density elements. It can reduce the number of gray-scale elements as much as possible to get the optimal topology with distinct boundaries in conjunction with the sensitivity filtering method based on particle swarm optimization (PSO). Several typical numerical examples are given to demonstrate this method. [ABSTRACT FROM AUTHOR]

This paper proposes a simple model selection test between the Gompertz and the Logistic growth models based on parameter significance testing in a comprehensive linear regression. Simulations studies are provided to show the accuracy of the method. Two real-data examples are also provided to illustrate the implementation of the proposed method in practice. [ABSTRACT FROM AUTHOR]

It is generally assumed that the daily probability of survival of mosquitoes is independent of age. To test this assumption we have conducted a three-year experimental fieldwork study (2005-2007) at Fortaleza-CE in Brazil, determining daily survival rates of the dengue vector Aedes aegypti (L.). Survival rates of adult Ae. aegypti may be age-dependent and the statistical analysis is a sensitive approach for comparing patterns of mosquito survival. The mosquito survival data were better fit by a Weibull survival function than by the more traditionally used Gompertz or logistic survival functions. Gompertz, Weibull, or logistic survival functions often fit the survival, and the tails of the survival curves usually appear to fall between the values predicted by the three functions. We corroborate that the mortality of Ae. aegypti in semi-natural conditions may no more be considered as a constant phenomenon during the life of adult mosquitoes but varies according to the age and environmental conditions under a tropical climate. This study estimates the variability in the survival rate of Ae. aegypti and environmental factors that are related to such variability. The statistical analysis shows that the fitting ability, concerning the hazard function, was in decreasing order: Seasonal Cox, the three-parameter Gompertz, and the three-parameter Weibull, that was similar to the three-parameter logistic. The advantage of using the Cox model is that it is convenient for exploring the relationship between survival and several explanatory variables. The Cox model has the advantage of preserving the variable in its original quantitative form and of using a maximum of information. The survival analyses indicate that mosquito mortality is both ageand environment-dependent. [ABSTRACT FROM AUTHOR]

Abstract: Based on Markov process and the nature of the growth curve regression equation, we establish joint prediction model of Markov and the Logistic growth curve, which can predict the future sugarcane production of Guangxi province, and we could proof its feasibility. [Copyright &y& Elsevier]

Abstract: The grape vine moth, Lobesia botrana (Denis and Schiffermüller) (Lepidoptera: Tortricidae), attacks vineyards mostly in Southern Europe and Northern Africa. The efficiency of most control methods depends on the treatment of pest populations at their most susceptible stages, therefore the prediction of the moth’s development cycle would help greatly in determining an optimal treatment schedule. One strategy for protecting against this pest is based on the day of maximum flight of males per generation (peak flight), when the mating between males and females and the laying of eggs reaches its maximum. The knowledge of these times would enable us to decide the kind of insecticide and the best time to target it. The time of maximum flight can be predicted by the Touzeau model of accumulated average daily temperature exceeding the development threshold. As shown, the fit of this model on data from the Ribera del Duero region in Spain is not accurate enough. Therefore, we propose an empirical and biologically plausible model based on logistic transformation of daily temperatures, which proves a better fit and permits simple inclusion of additional variables such as relative humidity. [Copyright &y& Elsevier]

Abstract: A three-part series presents the development of models for predicting the local thermal sensation (Part I) and local comfort (Part II) of different parts of the human body, and also the whole-body sensation and comfort responses (Part III). The models predict these subjective responses to the environment from thermophysiological measurements or predictions (skin and core temperatures). The models apply to a range of environments: uniform and non-uniform, transient and stable. They are based on diverse results from literature and from body-part-specific human subject tests in a climate chamber. They were validated against a test of passengers in automobiles. This series is intended to present the rationale, structure, and coefficients for these models so that others can test them and develop them further as additional empirical data becomes available. The experimental methods and some measured results from the climate chamber tests have been published previously. Part II describes a thermal comfort model with coefficients representing 19 individual local body parts. For each part, its local comfort is predicted from local and whole-body thermal sensations. These inputs are obtained from the sensation models described in Part I and III, or from measurements. [Copyright &y& Elsevier]

Abstract: A three-part series presents the development of models for predicting the local thermal sensation (Part I) and local comfort (Part II) of different parts of the human body, and also the whole-body sensation and comfort responses (Part III). The models predict these subjective responses to the environment from thermophysiological measurements or predictions (skin and core temperatures). The models apply to a range of environments: uniform and non-uniform, transient and stable. They are based on diverse results from the literature and from body part-specific human subject tests in a climate chamber. They were validated against a test of passengers in automobiles. This series is intended to present the rationale, structure, and coefficients for these models so that others can test and develop them further as additional empirical data becomes available. The experimental methods and some measured results from the climate chamber tests have been published previously. Part I describes thermal sensation models representing 19 individual local body parts. The models'' structure and coefficients were derived by regression of skin and core temperatures against thermal sensation votes obtained in the chamber experiments. The sensation for each local body part is predicted by a logistic function with four inputs: local skin temperature, mean-skin temperature presenting the whole-body thermal state, and the time derivatives of skin and core temperatures representing the response to transients. These inputs can be obtained from thermophysiological computer programs that treat the body as multiple segments. [Copyright &y& Elsevier]

The error backpropagation multi-layer perceptron algorithm is revisited. This algorithm is used to train and validate two models of three-layer neural networks that can be used to calibrate a 5-hole pressure probe. This paper addresses Occam's Razor problem as it describes the adhoc training methodology applied to improve accuracy and sensitivity. The trained outputs from 5-4-3 feed-forward network architecture with jump connection are comparable to second decimal digit (~0.05) accuracy, hitherto unreported in literature. [ABSTRACT FROM AUTHOR]

To evaluate the performance of knowledge management of a firm at certain time, an evaluation index system of knowledge management performance was established based on knowledge circulation process, compositive evaluation of knowledge circulation process index on the basis of weigh by D-S evidence theory was developed, and a logistic function was constructed to evaluate the knowledge management performance index (KMPI). Results of evaluation process and demonstration indicate that KMPI has positive correlation with three financial measures: knowledge asset, stock income ratio, and R&D expenditure, which proves that the proposed KMPI can represent the knowledge management efficiency. [ABSTRACT FROM AUTHOR]

Clothing adjustment is an essential way for people to adapt to the weather changes and maintain thermal comfort in an outdoor environment. In this study, it was assumed that outdoor clothing adjustment was influenced by the local past temperatures. With temperature changes, clothing adjustment could be divided into "free adjustment phase" and "restricted adjustment phase". Two consecutive years of outdoor field investigation experiments were conducted in 6 typical outdoor spaces in Changsha, China, which was hot in summer and cold in winter. During the field experiment, outdoor thermal environment parameters were measured in real-time, meanwhile, clothing and thermal comfort of participants were documented. The analysis results of field experiment data verified the assumption. 7876 effective samples were collected to build a creative outdoor clothing model (OCM) considering the weather characteristics of Changsha based on running mean temperature and four-parameter logistic function. The determination coefficient (R 2) of the OCM was 0.954, which was higher than the existing models. Moreover, prediction deviations were within 20% for 86% samples. According to the OCM, the range of running mean temperature corresponding to the free adjustment phase was 4 °C–24 °C for the Changsha residents. The free changes of clothing insulation during this phase enabled people to maintain thermal comfort in the outdoor environment. The OCM proposed in this study can provide a theoretical basis for evaluating outdoor thermal comfort and wearing appropriately according to the temperature. ● Clothing adjustment is the most essential means of thermal adaptation outdoors ● Outdoor clothing adjustment is influenced by the local past temperatures ● Clothing adjustment was divided into free and restricted adjustment phases ● A logistic function clothing model was proposed based on running mean temperature ●Clothing adjustment has a feedback effect on thermal comfort in outdoor environment [ABSTRACT FROM AUTHOR]

Copyright of Estudios Demográficos y Urbanos is the property of El Colegio de Mexico AC 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.)

• Electromyography correlates with voluntary torque during dynamic elbow flexion. • Models with electromyography and sensor measurements approximated torque. • A particle filter combined the models and considered their uncertainties. • The particle filter accurately estimated voluntary torque for ten healthy subjects. • Allows for future research on optimal assist-as-need control. Stroke is one of the leading causes of disability worldwide. Assist-as-need control is desirable as it can optimise the rehabilitation and potentially greatly improve the patient's recovery from stroke. However, to achieve optimal assistance, the voluntary effort a patient applies must be known. To verify the use of a particle filter to accurately estimate in real-time the voluntary torque from electromyography (EMG) for various subjects and movement speeds, accounting for the non-linear and time-varying behaviour of the muscle. Ten healthy subjects performed dynamic elbow flexion at various speeds. The EMG of the biceps brachii and the torque were recorded. A motion model and different sensor models were developed for each data set, and the particle filter was then applied to improve the estimate of voluntary torque. The performance of the particle filter with the different sensor models was analysed. By combining the motion model and sensor model, and considering their uncertainties, the particle filter improved the estimate of voluntary torque with a mean normalised RMS error across all subjects and movement speeds of 6.56 %. The particle filter demonstrated the ability to adapt and improve the estimate of voluntary torque, and so it is suitable for understanding the voluntary efforts and capabilities of a healthy subject. The next stages are to conduct a clinical trial to verify the effectiveness of the particle filter for subjects affected by stroke, and to analyse assist-as-need control based on the estimate of voluntary torque with a wide range of subjects. [ABSTRACT FROM AUTHOR]

The challenges of the most multi-objective particle swarm optimization (MOPSO) algorithms are to improve the selection pressure, equilibrate the convergence and diversity when tackling large-scale many-objective problems. To overcome these challenges, this paper proposes a novel PSO-based large-scale many-objective algorithm, named as LMPSO. In LMPSO, the Alpha-stable mutation is performed to enhance the diversity of swarm for avoiding premature convergence. And the parameters of PSO and Alpha-stable mutation are dynamically set following the Logistic function, which emphasize different convergence and diversity at different optimization stages. Moreover, LMPSO adopts a fitness to maintain the external archive, and the calculation of fitness is based on binary additive epsilon indicator. The binary indicator is also used to update the personal best of particles to avoid wrongly selecting dominance resistance solutions (DRSs). Aims for improving the selection pressure, the proposed algorithm employs a concept of dominance resistance error to identify the DRSs. To verify this idea, the DTLZ, ZDT, and LSMOP test suites with up to 1000 decision variables and 10-objective are used to qualify the performance of LMPSO. The simulations reveal the fact that the LMPSO significantly outruns the several chosen state-of-the-art algorithms when solving large-scale many-objective test instances. • A large-scale many-objective optimizer based on PSO is framed and named as LMPSO. • A new alpha-stable mutation together Logistic Function is presented. • The binary additive epsilon indicator is used to update the personal best. • Put forwards a new concept of dominance resistance error to identify the DRSs. [ABSTRACT FROM AUTHOR]

Wildfires are a major disturbance in the Mediterranean Basin and an ecological factor that constantly alters the landscape. In this context, it is crucial to understand where wildfires are more likely to occur as well as the drivers guiding them in complex landscapes such as the Mediterranean area. The objectives of this study are to estimate wildfire probability occurrence as a function of biophysical and human-related drivers, to provide an assessment of the relative impact of each driver and analyze the performance of machine learning techniques compared to traditional regression modeling. By employing an Artificial Neural Network model and fire data (2004–2012), we estimated wildfire probability across two geographical regions covering most of the Italian territory: Alpine and subalpine region and Insular and peninsular region. The high classification accuracy (0.68 for the Alpine and subalpine region and 0.76 for the Insular and peninsular region) and good performances of the technique (AUC values of 0.82 and 0.76, respectively) suggest that our model can be used in the areas studied to assess wildfire probability occurrence. We compared our model with a logistic function, which showed a weaker predictive power (AUC values of 0.78 for the Alpine and subalpine region and 0.65 for the Insular and peninsular region) compared to the Artificial Neural Network. In addition, we assessed the importance of each variable by isolating it in the model. The importance of an individual variable differed between the two regions, underscoring the high diversity of wildfire occurrence drivers in Mediterranean landscapes. Results show that in the Alpine and subalpine region, the presence of forest is the most important variable, while climate resulted as being the most important variable in the Insular and peninsular region. The majority of areas recently affected by large wildfires in both regions have been correctly classified by the ANN model as 'high fire probability'. Hence, the use of an Artificial Neural Network is efficient and robust for understanding the probability of wildfire occurrence in Italy and other similar complex landscapes. • Artificial neural network (ANN) for estimating probability of wildfire occurrence. • ANN shows a more robust predictive power than regressive models. • Shrublands was surprisingly less important than the other land cover variables. • Human predictors do not show much importance individually. • The importance of each single driver differs among the study areas. [ABSTRACT FROM AUTHOR]

• WEEE generated in Vietnam during the period 2015–2050 was estimated. • Three scenarios in terms of lifespan were analyzed. • The relationship between lifespan and GDP per capita was considered. • The uncertainties related to the lifespan were covered to some extent. During recent decades, rapid urbanization, an increase in population, and a change in lifestyle have generated a significant amount of waste electrical and electronic equipment (WEEE). To develop sustainable and efficient WEEE management policies, particularly in developing countries such as Vietnam, it is of paramount importance to forecast the amount of WEEE generation expected in the future. In the input-output approach as one of the WEEE estimation models, the determination of EEE lifespan is a major concern because it can be dynamic with time and vary with socioeconomic situations. Therefore, three scenarios were considered on the basis of the association of lifespan with gross domestic product per capita. By considering the lifespan transition, this study estimated the potential amount of WEEE, particularly large home appliances including refrigerators, washing machines, air conditioners, and televisions generated in Vietnam and the relative volume of obsolete metals contained in the WEEE during the period 2015–2050. For this, it employed a population balance model, logistic function, and Weibull distribution. It was found that the estimated weight of WEEE discarded in Vietnam during 2050 is mitigated 50% under the case where the lifespan transition is considered, compared to the case where the lifespan transition is not considered. By considering the relationship between lifespan and GDP per capita in estimating potential WEEE, this study to some extent covered the uncertainties related to the lifespan and can consequently contribute to the enhancement of e-waste estimation. [ABSTRACT FROM AUTHOR]