Product line design

We characterize the product line choice and pricing of a monopolist from the upper envelope of net marginal revenue curves to the individual product demand functions. The equilibrium product line constitutes those varieties yielding the highest upper envelope. In a generalized vertical differentiation framework, the equilibrium line is exactly the same as the first-best socially optimal line. These upper envelope and first-best optimal line findings extend to symmetric Cournot oligopoly

Fluid Flows of Mixed Regimes in Porous Media

In porous media, there are three known regimes of fluid flows, namely, pre-Darcy, Darcy and post-Darcy. Because of their different natures, these are usually treated separately in literature. To study complex flows when all three regimes may be present in different portions of a same domain, we use a single equation of motion to unify them. Several scenarios and models are then considered for slightly compressible fluids. A nonlinear parabolic equation for the pressure is derived, which is degenerate when the pressure gradient is either small or large. We estimate the pressure and its gradient for all time in terms of initial and boundary data. We also obtain their particular bounds for large time which depend on the asymptotic behavior of the boundary data but not on the initial one. Moreover, the continuous dependence of the solutions on initial and boundary data, and the structural stability for the equation are established.Comment: 33 page

Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells

Perovskite solar cells (PSCs) have emerged as a promising option for solar energy generation. However, it is essential to consider the environmental impact of these innovative photovoltaic (PV) technologies as the industry moves towards commercialization. Researchers are currently exploring ways to recycle PSCs to recover valuable materials and reduce their environmental impact at the end of their life. To ensure the sustainability of PSCs, this study evaluates and compares the environmental impacts of five recently developed recycling approaches. The Tool for Reduction and Assessment of Chemicals (TRACI) method was utilized to measure environmental impacts in categories such as acidification (kg SO2-eq.), ecotoxicity (CTUe), eutrophication (kg Neq), GWP (kg CO2-eq), human toxicity (CTUh), cancer and non-cancer, human health particular air (kg PM2.5-eq), ozone depletion (kg CFC11eq), and smog (kg O3-eq). The results indicate a novel recycling approach using potassium iodide (KI) solution has lower environmental impacts. In contrast, processes involving butyl-amine (BA), chlorobenzene, and dimethylformamide (DMF) have significantly higher environmental impacts arising from 1 to 3 times higher than the reference method, except for ozone depletion, ~7 to 10 times higher than the reference

Implicit threat vigilance among violent offenders diagnosed with antisocial personality disorder:The impact of ostracism and control threat

The present study investigated the role of control as a moderator in reaction to ostracism among male violent offenders diagnosed with ASPD (N = 33) compared to a control sample consisting of males from the normal population without a known history of violence, or diagnosis of ASPD, matched for age and educational level (N = 35). Participants played an altered version of the Cyberball game in which they could control the course of the game or not. The authors predicted and found that having control prior to ostracism would mitigate the effect of ostracism on implicit threat vigilance among violent offenders diagnosed with ASPD, but not among normal individuals. The results suggest that control needs are crucial in the typology of ASPD

Sedation and Analgesia in Intensive Care: A Comparison of Fentanyl and Remifentanil

Optimal sedation and analgesia are of key importance in intensive care. The aim of this study was to assess the quality of sedoanalgesia and outcome parameters in regimens containing midazolam and either fentanyl or remifentanil. A prospective, randomized, open-label, controlled trial was carried out in the ICU unit of a large teaching hospital in Istanbul over a 9-month period. Thirty-four patients were randomly allocated to receive either a remifentanil-midazolam regimen (R group, n = 17) or a fentanyl-midazolam regimen (F group, n = 17). A strong correlation between Riker Sedation-Agitation Scale (SAS) and Ramsey Scale (RS) measurements was observed. Comparatively, remifentanil provided significantly more potent and rapid analgesia based on Behavioral-Physiological Scale (BPS) measurements and a statistically nonsignificantly shorter time to discharge. On the other hand, remifentanil also caused a significantly sharper fall in heart rate within the first six hours of treatment

Variable frame based Max-Weight algorithms for networks with switchover delay

This paper considers the scheduling problem for networks with interference constraints and switchover delays, where it takes a nonzero time to reconfigure each service schedule. Switchover delay occurs in many telecommunication applications such as satellite, optical or delay tolerant networks (DTNs). Under zero switchover delay it is well known that the Max-Weight algorithm is throughput-optimal without requiring knowledge of the arrival rates. However, we show that this property of Max-Weight no longer holds when there is a nonzero switchover delay. We propose a class of variable frame based Max-Weight (VFMW) algorithms which employ the Max-Weight schedule corresponding to the beginning of the frame during an interval of duration dependent on the queue sizes. The VFMW algorithms dynamically adapt the frame sizes to the stochastic arrivals and provide throughput-optimality without requiring knowledge of the arrival rates. Numerical results regarding the application of the VFMW algorithms to DTN and optical networks demonstrate a good delay performance.National Science Foundation (U.S.) (NSF grant CNS-0626781)National Science Foundation (U.S.) (NSF grant CNS-0915988)United States. Army Research Office (ARO Muri grant number W911NF-08-1-0238

Measuring movement fluency during the sit-to-walk task

Restoring movement fluency is a key focus for physical rehabilitation; it's measurement, however, lacks objectivity. The purpose of this study was to find whether measurable movement fluency variables differed between groups of adults with different movement abilities whilst performing the sit-to-walk (STW) movement. The movement fluency variables were: (1) hesitation during movement (reduction in forward velocity of the centre of mass; CoM), (2) coordination (percentage of temporal overlap of joint rotations) and (3) smoothness (number of inflections in the CoM jerk signal)