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Abstract This paper presents the experimental characterization and modeling of a scroll expander. The expander used here is a scroll compressor modified to work as an expander. It is characterized in two experimental setups using air and ammonia as working fluids. The paper studies how the main operating variables (supply pressure and temperature, pressure ratio, rotational speed and lubrication) influence the performance of the scroll expander. A semi-empirical model is proposed to determine the scroll expander performance. This model uses some semi-empirical parameters (such as built-in volume ratio, leakage area and mechanical losses), obtained through experimentation, to calculate the mechanical power, supply mass flow rate and exhaust temperature. Using this semi-empirical model, the deviations in the calculated mechanical power, exhaust temperature and supply mass flow rate are ±9%, ±4 K and ±5% Hz.

Background: Impairments in decision making are a consistent finding in substance use disorder (SUD) populations. However, decision‐making deficits are not specific for SUDs and are also reported in the context of other psychiatric disorders such as antisocial and borderline personality disorders (PDs). Given the frequent comorbidity between SUD and cluster B PD, it might be questioned whether the decision‐making impairments typically reported in SUD populations reflect the addictive disorder, the cluster B PD, or a combination of the 2.Methods: In the current study, we compare the decision‐making performance of non–substance‐abusing controls (n=53) on the Iowa Gambling Task (IGT) with the decision‐making performance of 3 abstinent alcohol‐dependent samples, i.e., alcoholic patients without any PD (n=38), alcoholic patients with a cluster A or C PD (n=19), and alcoholic patients with a cluster B PD (n=23).Results: Overall, all 3 alcohol‐dependent subsamples performed inferior compared with controls. Between alcoholic subsamples, the alcoholic patients with a cluster A or C PD had the highest IGT score, followed by the alcoholic patients without a PD, while the cluster B alcoholic patients were the most impaired.Conclusion: These findings suggest that impairments in decision making underlie both alcohol dependence and cluster B PD, and alcoholic patients with a comorbid cluster B PD are particularly impaired in their decision making. These deficits may underlie the severe problems that characterize cluster B alcoholic patients specifically in inappropriate behaviors (e.g., poly substance abuse, legal, and professional dysfunction).

Abstract Biogas production is one of the number of tools that may be used to alleviate the problems of global warming, energy security and waste management. Biogas plants can be difficult to sustain from a financial perspective. The facilities must be financially optimized through use of substrates with high biogas potential, low water content and low retention requirement. This research carried out in laboratory scale batch digesters assessed the biogas potential of energy crops (maize and grass silage) and solid manure fractions from manure separation units. The ultimate methane productivity in terms of volatile solids (VS) was determined as 330, 161, 230, 236, 361 L/kg VS from raw pig slurry, filter pressed manure fiber (FPMF), chemically precipitated manure fiber (CPMF), maize silage and grass silage respectively. Methane productivity based on mass (L/kg substrate) was significantly higher in FPMF (55 L/kg substrate), maize silage (68 L/kg substrate) and grass silage (45–124 L/kg substrate (depending on dry solids of feedstock)) as in comparison to raw pig slurry (10 L/kg substrate). The use of these materials as co-substrates with raw pig slurry will increase significantly the biomethane yield per unit feedstock in the biogas plant.

This work describes an analysis of the impact of distributed generation, focusing on the generation from renewable sources, in the technical losses of electrical energy distribution systems. To do so, the OPENDSS software was used to simulate the operation of two distribution feeders, considering: (a) different generation penetration levels; (b) generation with different power factors; (c) variations in the location of distributed sources in the distribution system. The results show that these factors can both interfere positively (decrease) or negatively (increase) in the distribution network technical losses levels, and therefore, there may be distortions in the recognized electrical losses by regulatory agencies, mainly due to the generation unpredictability of renewable sources.

In the past five years, perovskite solar cells (PSCs) based on organometal halide perovskite have exhibited extraordinary photovoltaic (PV) performance. However, the PV measurements of PSCs have been widely recognized to depend on voltage scanning condition (hysteretic current density-voltage [J-V] behavior), as well as on voltage treatment history. In this study, we find that varied PSC responses are attributable to two causes. First, capacitive effect associated with electrode polarization provides a slow transient non-steady-state photocurrent that modifies the J-V response. Second, modification of interfacial barriers induced by ion migration can modulate charge-collection efficiency so that it causes a pseudo-steady-state photocurrent, which changes according to previous voltage conditioning. Both phenomena are strongly influenced by ions accumulating at outer interfaces, but their electrical and PV effects are different. The time scale for decay of capacitive current is on the order of seconds, whereas the slow redistribution of mobile ions requires several minutes.

Hydraulic experiments using physical scale models of monopile scour protections typically have high ex-perimental uncertainties and data scattering. These uncertainties may severely affect the accuracy of the experimental results and need to be analysed quantitatively. This paper presents a study on the quantification of experimental uncertainties in monopile scour protection damage tests following the Guide to the expression of Uncertainty in Measurement (GUM) (ISO, 2008). The uncertainty analysis is performed using the three-dimensional damage number S3D and the widely applied STAB number. Through the analysis of the S3D number from individual test and repeated tests, it is found that the uncertainty analysis method for an individual test can be efficiently applied to predict the experimental uncertainty. The wave peak period and the current velocity are identified as the two major sources of uncertainties for the S3D number. The flow turbulence and correlations between input parameters can be neglected when estimating the uncertainty. The uncertainty analysis of the STAB number shows that the experimental uncertainty due to measurement can be up to 5% to 7% of the obtained STAB result. This uncertainty range is wide in comparison with the narrow margin of a dynamic scour protection design in DNV's recent recommended practice (DNV-RP-0618). The uncertainty of the STAB number is more affected by the armour stone density, wave peak period and significant wave height.

The Carpathian mountain region is one of the most significant natural refuges on the European continent. It is home to Europe’s most extensive tracts of montane forest, the largest remaining virgin forest and natural mountain beech-fir forest ecosystems. Adding to the biodiversity are semi-natural habitats such as hay meadows, which are the result of centuries of traditional land management. Like other mountain regions areas, the Carpathian mountain region provides important ecosystem goods and services such as water provision, food products, forest products and tourism. But these ecosystem services are feared to be under threat from climate change.This chapter reports on climate trends, impacts and adaptation options. Analysis of climate trends show an increase in annual mean temperature of 1.1–2.0 °C over the last 50 years (1961–2010), further increasing by 3.5–4.0 °C towards the end of the century. Precipitation changes are dispersed with an increase of 300–400 mm in the north and decrease of 100–150 mm in the south regions. Summer precipitation is projected to reduce by 20 %, whereas winter precipitation is projected to increase in most areas by 5–20 % by the year 2100. Both future scenarios and observations show high spatial variability and uncertainty. The same holds for the impacts on the investigated sectors water resources, forests, wetlands, grasslands, agriculture and tourism.The review of climate trends and adaptation options, inspired a strategic agenda on adaptation to be implemented under the regional Carpathian Convention. Planning for climate change adaptation benefits from transnational cooperation because many impacts relate to seasonal and geographical shifts across borders. This is true for the natural system (e.g. shifts in species distribution and snow cover) as well as for socio-economic activities like agriculture, forestry and tourism (e.g. shifting opportunities for growing crops and changes in the tourist season). Examples of adaptation exist, yet need to be communicated for wider adoption. Essential components of adaptation will be capacity building and information sharing, climate-proofing of infrastructure and investments, promotion of eco-system based adaptation measures and making biodiversity management more dynamic.

Abstract Abuse of market power by dominant generation firms is a growing concern in worldwide electricity markets. This paper argues that relying only on general competition rules—as is the case in most European countries—is insufficient and that complementary ex-ante regulation is needed. In particular, regulators should incentivize firms to sign contracts with retailers by regulating their risk exposure. In a simulation model we show that this type of regulation can significantly reduce the deadweight loss in the market, without imposing large costs on regulatees.