Investment in Electricity Markets with Asymmetric Technologies

We study competition between hydro and thermal electricity generators under de- mand uncertainty. Producers compete in quantities and each is constrained: the ther- mal generator by capacity and the hydro generator by water availability. We analyze a two-period game emphasizing the incentives for capacity investments by the ther- mal generator. We characterize both Markov perfect and open-loop equilibria. In the Markov perfect equilibrium, investment is discontinuous in initial capacity and higher than it is in the open-loop equilibrium. However, since there are two distortions in the model, equilibrium investment can be either higher or lower than the ecient investment.Electricity markets; Dynamic game; Duopoly; Capacity investment.

Dynamic Competition in Electricity Markets: Hydroelectric and Thermal Generation

We study competition between hydro and thermal electricity generators that face uncertainty over demand and water flows where the hydro generator is constrained by water flows and the thermal generator by capacity. We compute the Feedback equilibrium for the in?nite horizon game and show that there can be strategic withholding of water by the hydro generator. When water inflow is relatively low, however, the hydro generator may use more water than efficient as it faces an inefficiently low shadow price of water in this case. The inefficiency of the market outcome is tempered by the capacity constraints: for a large range of possible thermal production capacities and water flow levels, welfare loss under the duopoly market structure is much less than would occur in the absence of water and capacity constraints.Electricity markets; Electricity markets; Hydroelectricity; Imperfect Competition

Gasoline content regulation and compliance among US refineries

The US refining industry is a leading producer of sulfur oxide and nitrogen oxide emissions. As a result of the Clean Air Act, it has been subject to a host of environmental regulations that prescribe the production processes firms can employ and limits their emissions based on the permits they hold. Refiners must also produce gasoline that varies in quality by location to meet local, state and federal air quality standards. Empirical evidence suggests that a much larger proportion of firms in the industry have been non-compliant with Clean Air Act statutes than in other industries. We study the link between gasoline content regulation and the compliance behavior of refineries. We find that in areas with more stringent gasoline regulation, there was increased compliance on the part of firms

Variational Temporal IRT: Fast, Accurate, and Explainable Inference of Dynamic Learner Proficiency

Dynamic Item Response Models extend the standard Item Response Theory (IRT) to capture temporal dynamics in learner ability. While these models have the potential to allow instructional systems to actively monitor the evolution of learner proficiency in real time, existing dynamic item response models rely on expensive inference algorithms that scale poorly to massive datasets. In this work, we propose Variational Temporal IRT (VTIRT) for fast and accurate inference of dynamic learner proficiency. VTIRT offers orders of magnitude speedup in inference runtime while still providing accurate inference. Moreover, the proposed algorithm is intrinsically interpretable by virtue of its modular design. When applied to 9 real student datasets, VTIRT consistently yields improvements in predicting future learner performance over other learner proficiency models.Comment: 9 pages, 16th International Conference on Educational Data Mining (EDM'23

Brachyspira pilosicoli bloodstream infections: Case report and review of the literature

Brachyspira pilosicoli is the etiologic agent of human and animal intestinal spirochetosis and is rarely implicated as a cause of bacteremia. Here, we describe the case of a B. pilosicoli spirochetemia in a 53-year-old male patient suffering from cardiogenic shock. This fastidious bacterium was isolated from blood, likely after translocation from the intestinal tract. Blood cultures were positive after 5 days of incubation (one day after the patient's death), highlighting the problem of the recovery of such type of fastidious bacterium. Identification was achieved by molecular methods (16S rRNA sequencing). A review of the English literature found only 8 cases of bacteremia caused by B. pilosicoli, mostly in immunocompromised or critically ill patients. Finally, difficulties in rapid and accurate diagnosis of B. pilosicoli bloodstream infections, in vitro antimicrobial susceptibility of human clinical isolates, and therapeutic options are discussed

Détermination de la granulométrie des aérosols dans les émissions canalisées : cas d'une cimenterie

National audienceMonitoring emissions of particles with a diameter smaller than 10 um (PM10) has become of growing interest. However, measuring such particles is rather difficult, it appears as a result necessary to develop and assess measurement methods for the monitoring of PM10 from stack and fugitive emissions. The aim of the GAEC program [Granulometrie des Aerosols dans les Emissions Canalisees : Aerosol size distribution from stack emissions] is double : developing monitoring methods and improving knowledge on fine particulate stack emissions. Three institutes are involved in the program : Sechaud Environnement (formerly LECES), INERIS and CERTAM. This paper concems the results obtained from the first two steps of the program: a state of the art of the available techniques, the evaluation of the selected techniques during a sampling campaign at a cement plant.Face à l'intérêt grandissant concernant les émissions de particules de diamètre inférieur à 10 um et aux difficultés rencontrées lors de la mesure de ces particules, des développements métrologiques et l'évaluation des méthodes de mesurage en émissions canalisées et diffuses sont nécessaires. Le projet GAEC [Granulométrie des Aérosols dans les Emissions Canalisées] s'inscrit dans ce double contexte de développement métrologique et d'amélioration, des connaissances sur les sources d'émission de particules fines. Il porte plus précisément sur la "Détermination de la granulométrie des aérosols dans les émissions industrielles canalisées : PM10, PM(2,5), PM(1), et PM(0,1)". Il réunit trois partenaires : Séchaud Environnement (anciennement LECES), INERIS et CERTAM. L'intervention proposée ici a pour objectif de rapporter les résultats obtenus lors des deux premières phases du projet, à savoir : une étude bibliographique de l'état de l'art sur les techniques de mesure disponibles,la mise en oeuvre des techniques retenues lors d'une campagne de mesure menée sur une cimenterie

Patient-ventilator asynchrony during non-invasive ventilation for acute respiratory failure: a multicenter study

Objective : To determine the prevalence of patient-ventilator asynchrony in patients receiving non-invasive ventilation (NIV) for acute respiratory failure. Design : Prospective multicenter observation study. Setting : Intensive care units in three university hospitals. Methods: Patients consecutively admitted to ICU were included. NIV, performed with an ICU ventilator, was set by the clinician. Airway pressure, flow, and surface diaphragmatic electromyography were recorded continuously for 30min. Asynchrony events and the asynchrony index (AI) were determined from visual inspection of the recordings and clinical observation. Results: A total of 60 patients were included, 55% of whom were hypercapnic. Auto-triggering was present in 8 (13%) patients, double triggering in 9 (15%), ineffective breaths in 8 (13%), premature cycling 7 (12%) and late cycling in 14 (23%). An AI>10%, indicating severe asynchrony, was present in 26 patients (43%), whose median (25-75 IQR) AI was 26 (15-54%). A significant correlation was found between the magnitude of leaks and the number of ineffective breaths and severity of delayed cycling. Multivariate analysis indicated that the level of pressure support and the magnitude of leaks were weakly, albeit significantly, associated with an AI>10%. Patient comfort scale was higher in pts with an AI<10%. Conclusion: Patient-ventilator asynchrony is common in patients receiving NIV for acute respiratory failure. Our results suggest that leaks play a major role in generating patient-ventilator asynchrony and discomfort, and point the way to further research to determine if ventilator functions designed to cope with leaks can reduce asynchrony in the clinical settin