Large-scale unit commitment under uncertainty: an updated literature survey

The Unit Commitment problem in energy management aims at finding the optimal production schedule of a set of generation units, while meeting various system-wide constraints. It has always been a large-scale, non-convex, difficult problem, especially in view of the fact that, due to operational requirements, it has to be solved in an unreasonably small time for its size. Recently, growing renewable energy shares have strongly increased the level of uncertainty in the system, making the (ideal) Unit Commitment model a large-scale, non-convex and uncertain (stochastic, robust, chance-constrained) program. We provide a survey of the literature on methods for the Uncertain Unit Commitment problem, in all its variants. We start with a review of the main contributions on solution methods for the deterministic versions of the problem, focussing on those based on mathematical programming techniques that are more relevant for the uncertain versions of the problem. We then present and categorize the approaches to the latter, while providing entry points to the relevant literature on optimization under uncertainty. This is an updated version of the paper "Large-scale Unit Commitment under uncertainty: a literature survey" that appeared in 4OR 13(2), 115--171 (2015); this version has over 170 more citations, most of which appeared in the last three years, proving how fast the literature on uncertain Unit Commitment evolves, and therefore the interest in this subject

Evidence-based Kernels: Fundamental Units of Behavioral Influence

This paper describes evidence-based kernels, fundamental units of behavioral influence that appear to underlie effective prevention and treatment for children, adults, and families. A kernel is a behavior–influence procedure shown through experimental analysis to affect a specific behavior and that is indivisible in the sense that removing any of its components would render it inert. Existing evidence shows that a variety of kernels can influence behavior in context, and some evidence suggests that frequent use or sufficient use of some kernels may produce longer lasting behavioral shifts. The analysis of kernels could contribute to an empirically based theory of behavioral influence, augment existing prevention or treatment efforts, facilitate the dissemination of effective prevention and treatment practices, clarify the active ingredients in existing interventions, and contribute to efficiently developing interventions that are more effective. Kernels involve one or more of the following mechanisms of behavior influence: reinforcement, altering antecedents, changing verbal relational responding, or changing physiological states directly. The paper describes 52 of these kernels, and details practical, theoretical, and research implications, including calling for a national database of kernels that influence human behavior

Humans optional? Automatic large-scale test collections for entity, passage, and entity-passage retrieval

Manually creating test collections is a time-, effort-, and cost-intensive process. This paper describes a fully automatic alternative for deriving large-scale test collections, where no human assessments are needed. The empirical experiments confirm that automatic test collection and manual assessments agree on the best performing systems. The collection includes relevance judgments for both text passages and knowledge base entities. Since test collections with relevance data for both entity and text passages are rare, this approach provides a cost-efficient way for training and evaluating ad hoc passage retrieval, entity retrieval, and entity-aware text retrieval methods

EFFECTS OF BREATHING COOL AIR DURING EXERCISE IN THE HEAT ON THERMOREGULATION, PERCEPTION AND CYCLING PERFORMANCE

Cory L. Butts, Brendon P. McDermott, Christian B. Ridings, Elizabeth M. Demartini, James Grant, Nicole E. Moyen, Jenna M. Burchfield, Matthew S. Ganio & Stavros A. Kavouras, FACSM University of Arkansas, Fayetteville, Arkansas Limited research exists investigating the physiological effects of breathing cold air during exercise as a method of attenuating increases in core temperature. PURPOSE: Determine the effects of breathing cooled air during exercise on physiological, perceptual and subsequent performance responses. METHODS: Twelve trained male cyclists (age 26.5±3.6 y, height 1.81±0.05 m, body mass 73.5±7.9 kg, body fat 13.7±7.0%, VO2max 57.6±7.9 ml/kg/min) completed three trials in an environmental chamber (31°C, 55% RH) consisting of 75 min cycling at 59.1±4.8% VO2max, a performance 5 km time trial, and a 15 min cool down. Participants breathed on:off the CoreCooler device (water bottle providing cold air) at a low intermittent (LI) ratio of 1:4 min with inspired air temperature (TIA) of 19.8±3.7°C, high intermittent (HI) ratio of 2.5:2.5 min (TIA, 19.4±4.2°C), or control (CN) breathing warm air at 1:4 min (TIA, 30.8±1.6°C) during cycling and cool down. Gastrointestinal temperature (TGI), heart rate (HR), blood pressure (BP), perceived thirst, thermal sensation, and rating of perceived exertion (RPE) were collected every 15 min during cycling and every 5 min during performance and cool down. RESULTS: No differences were found in TGI (p=.827), HR (p=.363), MAP (p=.055), Thirst (p=.140), RPE (p=.056) between conditions at any time points. The rate of rise in core temperature was not attenuated in LI (0.014±0.005°C/min, p=1.00) or HI (0.008±0.005°C/min, p=.10) compared with CN (0.013±0.005°C/min). Systolic BP was greater at 45 minutes of cycling in HI (193.8±20.7 mmHg) versus CN (176.1±15.6 mmHg, p= .039). Thermal sensation was lower in LI than CN at the end of performance (CN 6.7±0.7, LI 6.0±0.7, p=.039) and both LI (CN 4.3±0.8, LI 3.8±0.7, p=.006) and HI (HI 3.7±0.7, p=.006) were lower at the end of cool down. Performance times were not different following LI (23.7±4.2 min, p=.279) or HI (23.6±4.2 min, p=.192) compared to CN (24.6±3.9 min). CONCLUSION: The utilization of the CoreCooler device at both LI and HI frequencies decreased thermal sensation, however no differences in physiological responses or performance were identified. This research was funded by CoreCooler Company, LLC