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In this study, the performance of a forced convection mixed-mode solar dryer with thermal energy storage is experimentally analyzed. The main goal was to develop an efficient and cost effective dryer that maintains drying process after sunset. The dryer mainly consists of a solar collector/absorber, drying chamber and a fan. A photovoltaic panel and battery storage are also integrated with the dryer to supply the required electrical energy. The experiments are carried out to dry fresh apricot slices at different working conditions. The effect of using phase change material to store thermal energy during daytime is analyzed. It is concluded that the performance of the solar collector is improved and the drying process is effectively extended when solar energy was not available. It is also observed that the rate of drying is almost constant along the drying chamber. The moisture pick-up efficiency and the overall thermal efficiency of the dryer are about 10% and 11%, respectively. [ABSTRACT FROM AUTHOR]

Fatigue is one of the factors leading to reduction in productivity, poor quality of work and increased risk of accidents in construction. Existing established methods of assessing fatigue include surveys and questionnaires, which are cumbersome to implement at construction sites. This study presents a novel approach for real time monitoring of physical fatigue in construction workers using wearable sensors. Changes in the heart rate, thermoregulation and electrical brain activity during a simulated construction task were monitored from 12 participants using a heart rate monitor, infrared temperature sensors and an EEG sensor. Borg's RPE was used as a subjective scale to collect the level of fatigue experienced by the participants. Boosted tree classifiers were trained using the features extracted from the heart rate and temperature sensor signals and used to predict the level of physical fatigue. Only physical fatigue was assessed as none of the participants developed any sign of mental fatigue during the study. The results show that physical fatigue can be monitored using wearable sensors. The classification accuracy, based solely on features extracted from average of skin temperature data, was 9% higher than based solely on heart rate data, and combining the information from both sensors resulted in the best accuracy of 82%. The results also show that monitoring thermoregulation from temple can be more useful compared to other studied monitoring sites, the classification accuracy based only on data from the temple was 79%. This accuracy is significantly higher compared to the classification accuracy based only on heart rate data (59%). [ABSTRACT FROM AUTHOR]

The objective of this paper is to explore the skill acquisition process of informal economy workers and how it affects their current skills and productivity levels. We used a mixed method and multilevel sampling design with the aid of questionnaires and interviews. We found that trainings provided and skill-levels of workers were basic, and this affected their performance and productivity. We recommend that skill development policies for informal economy workers need to be specific, comprehensive, all-inclusive and peculiar to their challenges. [ABSTRACT FROM AUTHOR]

Abstract: Food safety regulations are evolving to performance-based regimes in which firms have greater flexibility and responsibility in adopting effective controls. Within such a context, this paper compares performance and process standards modeling the variability of industry-level compliance and therefore the resultant level of food safety. Monte Carlo simulations are conducted manipulating five factors: the variances of input use of efficient and inefficient firms, the proportion of inefficient firms in the industry, the mean of the error term for inefficient firms, and the policymakers’ risk preferences. Results suggest that process standards may be preferred over performance standards under certain circumstances. [Copyright &y& Elsevier]

Abstract: This paper explores the possibility that unregulated FDI flows are causally implicated in the decline in labor productivity growth in semi-industrialized economies. These effects are hypothesized to operate through the negative impact of firm mobility on worker bargaining power and thus wages. Downward pressure on wages can reduce the pressure on firms to raise productivity in defense of profits, contributing to a low wage-low productivity trap. This paper presents empirical evidence, based on panel data fixed effects and GMM estimation for 37 semi-industrialized economies that supports the causal link between increased firm mobility and lower wages, as well as slower productivity growth over the period 1970–2000. [Copyright &y& Elsevier]

Abstract: This paper examines the argument that environmental performance standards offer a relative disincentive for the adoption of cleaner technologies, and it shows that this relative disincentive exists when regulators cannot credibly commit to a stringent environmental standard. The relative disincentive is alleviated if the firms are sufficiently heterogeneous in the adoption costs, if the regulator engages the firm repeatedly, or if the regulator can combine an environmental performance standard with another instrument, such as a subsidy to the adoption of a cleaner technology or fines for non-compliance. [Copyright &y& Elsevier]

Abstract: Recent analyses on different database have proposed some regularities with respect to size and growth rates distribution of firms. In this work we explore some basic properties of the dynamics of productivity in Italian manufacturing firms. We investigate relations between different inputs and output examining the impact of productivity in shaping the pattern of corporates evolution. [Copyright &y& Elsevier]

Abstract: This paper presents a load frequency control design for interconnected electric power systems using a set of fuzzy logic rules. The design objectives are (i) to comply with the North American Electric Reliability Council''s (NERC) control performance standards, CPS1 and CPS2, (ii) to reduce wear and tear of generating unit''s equipments, and (iii) to design a feasible control structure. A test system with multiple generation and distribution companies that takes into account regulation and load following services is used to demonstrate the effectiveness of the proposed methodologies. [Copyright &y& Elsevier]