TY - JOUR A1 - Boersch-Supan, Axel A1 - Weiss, Matthias T1 - Productivity and age: Evidence from work teams at the assembly line JF - Journal of the economics of ageing N2 - The authors study the relation between workers' age and their productivity in work teams, based on a new and unique data set that combines data on errors occurring in the production process of a large car manufacturer with detailed information on the personal characteristics of workers related to the errors. The authors correct for non-random sample selection and the potential endogeneity of the age-composition in work teams. The results suggest that productivity in this plant which is typical for large-scale manufacturing does not decline at least up to age 60. (C) 2016 Published by Elsevier B.V. KW - Age-productivity profiles KW - EARNINGS PROFILES KW - INCENTIVES KW - PERFORMANCE KW - SAMPLE KW - WAGES KW - WORKFORCE Y1 - 2016 U6 - https://doi.org/10.1016/j.jeoa.2015.12.001 IS - 7 SP - 30 EP - 42 PB - Elsevier ER - TY - JOUR A1 - Frazzica, Andrea A1 - Palomba, Valeria A1 - Dawoud, Belal A1 - Gullì, Giuseppe A1 - Brancato, Vincenza A1 - Sapienza, Alessio A1 - Vasta, Salvatore A1 - Freni, Angelo A1 - Costa, Fabio A1 - Restuccia, Giovanni T1 - Design, realization and testing of an adsorption refrigerator based on activated carbon/ethanol working pair JF - Applied Energy N2 - In the present paper design, realization and testing of a novel small scale adsorption refrigerator prototype based on activated carbon/ethanol working pair is described. Firstly, experimental activity has been carried out for identification of the best performing activated carbon available on the market, through the evaluation of the achievable thermodynamic performance both under air conditioning and refrigeration conditions. Once identified the best performing activated carbon, the design of the adsorber was developed by experimental dynamic performance analysis, carried out by means of the Gravimetric-Large Temperature Jump (G-LTJ) apparatus available at CNR ITAE lab. Finally, the whole 0.5 kW refrigerator prototype was designed and built. First experimental results both under reference air conditioning and refrigeration cycles have been reported, to check the achievable performance. High Specific Cooling Powers (SCPs), 95 W/kg and 50 W/kg, for air conditioning and refrigeration respectively, were obtained, while the COP ranged between 0.09 and 0.11, thus showing an improvement of the current state of the art. (C) 2016 Elsevier Ltd. All rights reserved. KW - Activated carbon KW - ADSORBENTS KW - adsorption KW - Ammonia KW - CARBON KW - CHILLER KW - COOLING SYSTEMS KW - Corrosion KW - DRIVEN KW - Ethanol KW - ETHANOL ADSORPTION KW - PERFORMANCE KW - Refrigeration KW - waste heat Y1 - 2016 U6 - https://doi.org/10.1016/j.apenergy.2016.04.080 VL - 174 SP - 15 EP - 24 PB - Elsevier ER - TY - JOUR A1 - Braun, Peter A1 - Gebhard, Jürgen A1 - Matysik, Frank-Michael A1 - Rabl, Hans-Peter T1 - Potential Technical Approaches for Improving Low-Temperature NOx Conversion of Exhaust Aftertreatment Systems JF - Chemie Ingenieur Technik N2 - Lean-burn engines, such as diesel engines, are widely used in mobile and stationary applications. Operation of lean-burn engines leads to formation of distinct amounts of nitrogen oxides (NO and NO2). Efficient aftertreatment is mandatory to meet legal requirements, especially at low exhaust temperatures, as for the future a decline of the exhaust temperature level can be predicted due to improved engine efficiencies. Within this review, potential technical solutions to enhance the DeNO(x)-aftertreatment efficiency at low exhaust temperatures are presented. KW - DECOMPOSITION KW - Diesel Engine KW - Exhaust aftertreatment KW - IMPACT KW - Low-temperature DeNO(x) KW - NH3 KW - NITRIC-OXIDE KW - Nitrogen oxides KW - OXIDE CATALYST KW - PERFORMANCE KW - PYROLYSIS KW - SCR KW - Selective catalytic reduction KW - SELECTIVE CATALYTIC-REDUCTION KW - UREA HYDROLYSIS Y1 - 2018 U6 - https://doi.org/10.1002/cite.201700122 VL - 90 IS - 6 SP - 762 EP - 773 PB - WILEY-VCH ER - TY - JOUR A1 - Dechant, Eduard A1 - Fedulov, Feodor A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Bandwidth Widening of Piezoelectric Cantilever Beam Arrays by Mass-Tip Tuning for Low-Frequency Vibration Energy Harvesting JF - Applied Science N2 - Wireless sensor networks usually rely on internal permanent or rechargeable batteries as a power supply, causing high maintenance efforts. An alternative solution is to supply the entire system by harvesting the ambient energy, for example, by transducing ambient vibrations into electric energy by virtue of the piezoelectric effect. The purpose of this paper is to present a simple engineering approach for the bandwidth optimization of vibration energy harvesting systems comprising multiple piezoelectric cantilevers (PECs). The frequency tuning of a particular cantilever is achieved by changing the tip mass. It is shown that the bandwidth enhancement by mass tuning is limited and requires several PECs with close resonance frequencies. At a fixed frequency detuning between subsequent PECs, the achievable bandwidth shows a saturation behavior as a function of the number of cantilevers used. Since the resonance frequency of each PEC is different, the output voltages at a particular excitation frequency have different amplitudes and phases. A simple power-transfer circuit where several PECs with an individual full wave bridge rectifier are connected in parallel allows one to extract the electrical power close to the theoretical maximum excluding the diode losses. The experiments performed on two- and three-PEC arrays show reasonable agreement with simulations and demonstrate that this power-transfer circuit additionally influences the frequency dependence of the harvested electrical power. KW - array KW - BAND-PASS FILTERS KW - bandwidth KW - BIMORPH KW - Optimization KW - OUTPUT KW - PERFORMANCE KW - piezoelectric cantilever KW - POWER KW - vibration energy harvesting Y1 - 2017 U6 - https://doi.org/10.3390/app7121324 N1 - Corresponding Author: Mikhail Shamonin VL - 7 IS - 12 PB - MDPI ER - TY - JOUR A1 - Koder, Alexander A1 - Schwanzer, Peter A1 - Zacherl, Florian A1 - Rabl, Hans-Peter A1 - Mayer, Wolfgang A1 - Gruber, Georg A1 - Dotzer, Thomas T1 - Combustion and emission characteristics of a 2.2L common-rail diesel engine fueled with jatropha oil, soybean oil, and diesel fuel at various EGR-rates JF - Fuel N2 - To investigate the combustion and emission behavior of straight vegetable oils (SVO), jatropha oil, soybean oil, and diesel fuel were tested. For this research, a 2.2L common-rail engine with a two-stage turbocharging concept was equipped with a cylinder pressure indication system, an exhaust-gas analyzer, an AVL Micro Soot sensor and a Scanning Mobility Particle Sizer 3936 (SMPS) device to detect the particle-size-distribution (PSD). At a low and mid-load engine-operating point (EOP), the thermodynamic and emissions were investigated under various exhaust gas recirculation (EGR) rates with respect to the PSD. Moreover, the injection behavior of the three test fuels was analyzed separately using an injection rate analyzer. This procedure facilitates the thermodynamic investigations of the engine process and allows the calculation of the hydraulic delay (HD) as well as the ignition delay (ID). The ID of the SVO fuels compared to diesel fuel was found to be lower at all engine-operating modes, while jatropha oil always showed the shortest ID. In the particulate-nitrogen oxide (NOX) trade-off, the SVO fuels showed higher particulate matter (PM) emissions at the low-load EOP, whereas the PM emissions of diesel fuel overtop the SVO fuels at a higher engine load. With increased EGR-rates, a rise in the particle size was observed for all fuels. At the low-load EOP, the SVO fuels showed larger particles for high EGR-rates. This effect also changed by increasing the engine-load to the mid-load EOP, wherein the particle size of the diesel fuel emissions is higher by applying elevated EGR-rates. KW - BEHAVIOR KW - BLENDS KW - Exhaust gas recirculation KW - IGNITION KW - INJECTION KW - Jatropha oil KW - KARANJA KW - Particle-size-distribution KW - PERFORMANCE KW - RME KW - Soybean oil KW - Straight vegetable oil combustion KW - VEGETABLE-OILS Y1 - 2018 U6 - https://doi.org/10.1016/j.fuel.2018.04.147 VL - 228 IS - September SP - 23 EP - 29 PB - Elsevier ER - TY - JOUR A1 - Palomba, Valeria A1 - Nowak, Sebastian A1 - Dawoud, Belal A1 - Frazzica, Andrea T1 - Dynamic modelling of Adsorption systems: a comprehensive calibrated dataset for heat pump and storage applications JF - Journal of energy storage N2 - The growing efforts for the development of clean and efficient energy systems require the use of a multi-disciplinary approach and the integration of multiple generation appliances. Among the fields that can be considered enabling technologies, adsorption systems for air conditioning and thermal energy storages, are constantly increasing their maturity. However, for a proper design and integration of such systems, there is the need for a simulation framework that is reliable and computationally convenient. In the present paper, the implementation of a dynamic model for adsorption systems is presented, which includes different components (adsorber, phase changer, sorption materials) and is structured as a library. Modelica language and the commercial software Dymola (R) are used for the analysis. Data for different heat exchangers and working pairs are calibrated using experimental results and the calibrated model is subsequently used for the design of an adsorber based on a plate heat exchanger for thermal energy storage applications. The results proved that the model is fast and can reproduce experimental results with good accuracy, thus being a useful tool for the design and optimization of the different components of sorption systems. KW - CHILLERS KW - DIFFUSION KW - ETHANOL ADSORPTION KW - Optimization KW - PERFORMANCE KW - SCALE KW - simulation KW - THERMAL-ENERGY STORAGE KW - TRANSFORMATION KW - WATER-ADSORPTION Y1 - 2021 U6 - https://doi.org/10.1016/j.est.2020.102148 VL - 33 PB - Elsevier ER -