Decision support tool for Virtual Power Players: Hybrid Particle Swarm Optimization applied to Day-ahead Vehicle-To-Grid Scheduling

This paper presents a decision support tool methodology to help virtual power players (VPPs) in the Smart Grid (SGs) context to solve the day-ahead energy resource scheduling considering the intensive use of Distributed Generation (DG) and Vehicle-To-Grid (V2G). The main focus is the application of a new hybrid method combing a particle swarm approach and a deterministic technique based on mixedinteger linear programming (MILP) to solve the day-ahead scheduling minimizing total operation costs from the aggregator point of view. A realistic mathematical formulation, considering the electric network constraints and V2G charging and discharging efficiencies is presented. Full AC power flow calculation is included in the hybrid method to allow taking into account the network constraints. A case study with a 33-bus distribution network and 1800 V2G resources is used to illustrate the performance of the proposed method.

Dynamic Approach and Testbed for Small and Medium Players Simulation in Smart Grid Environments

The Smart Grid environment allows the integration of resources of small and medium players through the use of Demand Response programs. Despite the clear advantages for the grid, the integration of consumers must be carefully done. This paper proposes a system which simulates small and medium players. The system is essential to produce tests and studies about the active participation of small and medium players in the Smart Grid environment. When comparing to similar systems, the advantages comprise the capability to deal with three types of loads – virtual, contextual and real. It can have several loads optimization modules and it can run in real time. The use of modules and the dynamic configuration of the player results in a system which can represent different players in an easy and independent way. This paper describes the system and all its capabilities.

Coalition of distributed generation units to Virtual Power Players - a game theory approach

Smart Grids (SGs) have emerged as the new paradigm for power system operation and management, being designed to include large amounts of distributed energy resources. This new paradigm requires new Energy Resource Management (ERM) methodologies considering different operation strategies and the existence of new management players such as several types of aggregators. This paper proposes a methodology to facilitate the coalition between distributed generation units originating Virtual Power Players (VPP) considering a game theory approach. The proposed approach consists in the analysis of the classifications that were attributed by each VPP to the distributed generation units, as well as in the analysis of the previous established contracts by each player. The proposed classification model is based in fourteen parameters including technical, economical and behavioural ones. Depending of the VPP strategies, size and goals, each parameter has different importance. VPP can also manage other type of energy resources, like storage units, electric vehicles, demand response programs or even parts of the MV and LV distribution network. A case study with twelve VPPs with different characteristics and one hundred and fifty real distributed generation units is included in the paper.

Gestão de Recursos Energéticos para Apoio à Operação dos Virtual Power Players

A liberalização dos mercados de energia elétrica e a crescente integração dos recursos energéticos distribuídos nas redes de distribuição, nomeadamente as unidades de produção distribuída, os sistemas de controlo de cargas através dos programas de demand response, os sistemas de armazenamento e os veículos elétricos, representaram uma evolução no paradigma de operação e gestão dos sistemas elétricos. Este novo paradigma de operação impõe o desenvolvimento de novas metodologias de gestão e controlo que permitam a integração de todas as novas tecnologias de forma eficiente e sustentável. O principal contributo deste trabalho reside no desenvolvimento de metodologias para a gestão de recursos energéticos no contexto de redes inteligentes, que contemplam três horizontes temporais distintos (24 horas, 1 hora e 5 minutos). As metodologias consideram os escalonamentos anteriores assim como as previsões atualizadas de forma a melhorar o desempenho total do sistema e consequentemente aumentar a rentabilidade dos agentes agregadores. As metodologias propostas foram integradas numa ferramenta de simulação, que servirá de apoio à decisão de uma entidade agregadora designada por virtual power player. Ao nível das metodologias desenvolvidas são propostos três algoritmos de gestão distintos, nomeadamente para a segunda (1 hora) e terceira fase (5 minutos) da ferramenta de gestão, diferenciados pela influência que os períodos antecedentes e seguintes têm no período em escalonamento. Outro aspeto relevante apresentado neste documento é o teste e a validação dos modelos propostos numa plataforma de simulação comercial. Para além das metodologias propostas, a aplicação permitiu validar os modelos dos equipamentos considerados, nomeadamente, ao nível das redes de distribuição e dos recursos energéticos distribuidos. Nesta dissertação são apresentados três casos de estudos, cada um com diferentes cenários referentes a cenários de operação futuros. Estes casos de estudos são importantes para verificar a viabilidade da implementação das metodologias e algoritmos propostos. Adicionalmente são apresentadas comparações das metodologias propostas relativamente aos resultados obtidos, complexidade de gestão em ambiente de simulação para as diferentes fases da ferramenta proposta e os benefícios e inconvenientes no uso da ferramenta proposta.

Detection of testosterone administration based on the carbon isotope ratio profiling of endogenous steroids: international reference populations of professional soccer players.

BACKGROUND AND OBJECTIVES: The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined. METHODS: Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS). RESULTS: Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases. CONCLUSIONS: The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids.

Monocarboxylate transporters: new players in body weight regulation.

Over the last two decades, several genes have been identified that appear to play a role in the regulation of energy homeostasis and body weight. For a small subset of them, a reduction or an absence of expression confers a resistance to the development of obesity. Recently, a knockin mouse for a member of the monocarboxylate transporter (MCT) family, MCT1, was demonstrated to exhibit a typical phenotype of resistance to diet-induced obesity and a protection from its associated metabolic perturbations. Such findings point out at MCTs as putatively new therapeutic targets in the context of obesity. Here, we will review what is known about MCTs and their possible metabolic roles in different organs and tissues. Based on the description of the phenotype of the MCT1 knockin mouse, we will also provide some insights about their putative roles in weight gain regulation.

A comparison of injuries among children and adult football (soccer) players

Football is a universal and an affordable game but we need to minimize the incidence of accidents among the increasing number of young football players. Our 11 year retrospective epidemiological study (1990-2000) of football injuries in children (N= 1000) was compared with those of adult players in the 2006 European Championship. This comparative study confirmed that the anatomical, biomechanical and biological conditions differ between adults and children and that they warrant particular attention to protect the latter vulnerable group against bone avulsions, overuse pathologies and fatigue-fractures. Injuries were shown to increase significantly with age up to 16 years (P=0.005). Children suffer mainly from contusions, fractures and sprain injuries. Head injuries were more common in boys (P=0.070), while girls were more prone to sprains. The types of injuries differ between adults and children (sprain versus fractures), the anatomical location of injuries is different (lower limbs in adults, lower and upper limbs in children), the circumstances of the injuries are different (contact in adults versus non-contact in children), and teenage girls have different types of injuries than teenage boys. An increased incidence of injuries is due to changes in the position of the center of gravity and in the morphotype during rapid growth. For these reasons it is mandatory to adapt the training to the age and sex of the players. It is unsafe to train children the same way as adults. The height, the weight and the speed of growth must be taken into account by the multidisciplinary team when organising the training programmes. -- Le football fait partie des sports les plus pratiqués au monde en raison de sa popularité et de son accessibilité économ ique. L'incidence des blessures liées à cette pratique doit être diminuée surtout chez les jeunes joueurs en raison de la croissance exponentielle du nombre de joueurs féminins et masculins. Une étude épidémiologique rétrospective sur 11 ans (1990-2000) a été réalisée chez les enfants victimes de blessures liées au football (N==1000), puis a été comparée aux données recueillies de l'UEFA lors d'un Championnat Européen en 2006 sur les lésions des joueurs adultes. Cette étude comparative confirme que les structures anatomiques, biologiques et les tensions biomécaniques chez l'enfant diffèrent de celles de l'adulte. Les enfants ont un risque plus élevé de souffrir d'avulsion osseuse et de fractures de fatigue que les adultes. Les blessures augmentent significativement avec l'âge jusqu'à 16 ans (P==0,005). Les traumatismes crâniens sont plus fréquents chez les garçons tandis que les entorses sont plus à risque chez les filles. Les adultes font plus souvent des entorses tandis que les enfants font plus de fractures. La localisation anatomique diffère également entre ces deux groupes (les membres inférieurs chez l'adulte et les membres inférieurs et supérieurs chez l'enfant). La circonstance des blessures diffère également (choc avec un autre joueur chez l'adulte et des blessures sans contact chez l'enfant). Chez les adolescents, les blessures des filles diffèrent de celles des garçons. L'augmentation chez les enfants de cette incidence est liée au déplacement lors de la croissance du centre de gravité, avec une maladresse accrue lors des phases de croissance. Pour toutes ces raisons, il est justifié d'adapter les entraînements de football en fonction de l'âge, du sexe et du morphotype. L'entrainement des enfants doit être différent de celui des adultes. Le poids, la taille et la vitesse de croissance doit être prise en compte dans des structures multidisciplinaires afin de permettre une meilleure longévité sportive des jeunes joueurs de football.

Validation of ice skating protocol to predict aerobic power in hockey players

Validation ofan Ice Skating Protocol to Predict Aerobic Power in Hockey Players In assessing the physiological capacity of ice hockey players, researchers have often reported the outcomes from different anaerobic skate tests, and the general physical fitness of participants. However, with respect to measuring the aerobic power of ice hockey players, few studies have reported a sport-specific protocol, and currently there is a lack of cohort-specific information describing aerobic power based on evaluations using an on-ice protocol. The Faught Aerobic Skating Test (FAST) uses an on-ice continuous skating protocol to induce a physical stress on a participant's aerobic energy system. The FAST incorporates the principle of increasing workloads at measured time intervals during a continuous skating exercise. Regression analysis was used to determine the estimate of aerobic power within gender and age level. Data were collected on 532 hockey players, (males=384, females=148) ranging in age between 9 and 25 years. Participants completed a laboratory test to measure aerobic power using a modified Bruce protocol, and the on-ice FAST. Regression equations were developed for six male and female, age-specific cohorts separately. The most consistent predictors were weight and final stage completed on the FAST. These results support the application of the FAST to estimate aerobic power among hockey players with R^ values ranging from 0.174 to 0.396 and SEE ranging from 5.65 to 8.58 ml kg' min'' depending on the cohort. Thus we conclude that FAST to be an accurate predictor of aerobic power in age and gender-specific hockey playing cohorts.

Collegiate volleyball players' need fulfillment, balance and well-being

Proponents of Basic Needs Theory (BNT; Deci & Ryan, 2002) contend that the mechanism underpinning psychological well-being is the fulfillment of basic psychological needs with their fulfillment addressed in an independent (Deci & Ryan, 2002) or balanced manner (Sheldon & Niemiec, 2006). The purpose of this investigation was to explore the associations between the fulfillment of basic psychological needs and two forms of psychological well-being, namely hedonic and eudaimonic indices. Employing purposive sampling and a cross-sectional design, collegiate volleyball players (N = 219; nfemales = 127) completed a battery of self-report instruments assessing psychological need satisfaction and well-being toward the mid-to-end portion oftheir competitive season. Aligned with BNT (Deci & Ryan, 2002) tenets and study hypotheses, results demonstrated that basic psychological need fulfillment was associated with psychological well-being in the context of volleyball. Albeit minimal, balanced need fulfillment was generally predictive of well-being indices beyond independent need contributions with suppressor effects noted. In sum, the results of the present investigation generally coincide with previous sport based BNT (e.g., Reinboth & Duda, 2006) and balanced need satisfaction (e.g., Sheldon & Niemiec, 2006) literature. Additional BNT support has been garnished and suggests that the fulfillment of the basic psychological needs for competence, autonomy, and relatedness may be targeted as the mechanisms to facilitate athletes' psychological well-being. Along with Ryan and Deci's (2007) recommendations, the outcomes of this investigation highlight the need for further empirical study ofBNT's tenets in the realm of sport including assessments of balanced need satisfaction as well as varied hedonic and eudaimonic indices.

Examining the influence of the coach athlete relationship on motivation and performance in female rugby players

The purpose of the study was two-fold; first, the association between interpersonal coaching styles and self-determined motivation was examined, followed by the investigation of the motivation-performance relationship. Participants included 221 female Canadian Interuniversity Sport (CIS) rugby players, aged sixteen to thirty-three (M= 20.1: SD = 2.26), who reported the number of years they played CIS rugby (M= 2.3: SD = 1.37) and organized rugby (M= 5.9: SD = 2.31). Multiple and bivariate regressions were employed with autonomy-support, structure, and involvement accounting for 17%, 41 % and 22% of the variance of competence, autonomy and relatedness. The three basic needs accounted for 40% of the variance of motivation, and motivation accounted for 2% of the variance of athletes' perceptions of performance. Findings indicated that autonomy-support emerged as a predictor of all three basic needs, involvement predicted relatedness and competence, autonomy predicted motivation, and motivation predicted athletes' perception of performance.

The Effect of a Stickhandling and Puck Control (SPC) Training Intervention on SPC Skills and Wrist Shot Performance Variables in Female Collegiate Ice Hockey Players

The purpose of the study was to investigate the effect of a 16 session stickhandling and puck control (SPC) off-ice training intervention on SPC skills and wrist shot performance variables. Eighteen female collegiate ice hockey players participated in a crossover design training intervention, whereby players were randomly assigned to two groups. Each group completed 16 SPC training sessions in two conditions [normal vision (NV) and restricted vision (RV)]. Measures obtained after the training intervention revealed significant improvements in SPC skills and wrist shot accuracy. Order of training condition did not reach significance, meaning that SPC improvement occurred as a result of total training volume as opposed to order of training condition. However, overall changes in the RV-NV condition revealed consistently higher effect sizes, meaning a greater improvement in performance. Therefore, support can be provided for this technical approach to SPC training and an alternative method of challenging SPC skills.

The effect of an eight session skate treadmill and agility training program on the degree of separation in ice hockey players

The sport of ice hockey places multiple simultaneous demands on the physiological, mechanical, and cognitive abilities of individual players. The purpose of the study was to investigate the effect of an eight session degree of separation (DOS) training intervention on sport specific measures of skating, stick handling and puck control movements in competitive ice hockey players. All participants completed a battery of pre and pos t skill and DOS specific tests designed to evaluate DOS abilities: Ttest of agility, a modified Cunningham Faulkner test of anaerobic capacity performed on a skate treadmill and a DOS skate treadmill test. Statistically significant differences were found between groups on the post test scores, meaning that the training intervention had a specific effect on the post test scores of the experimental group (p~O.05). Results of this investigation suggested that a DOS specific training program has the potential to enhance the integration and automation of or sequencing and coordination of uncoordinated ice hockey movements.

The Effect of Skate Blade Radius of Contour and Radius of Hollow on Skating Performance in Male Ice Hockey Players

The primary purpose of this study was to investigate the effect of skate blade shape on skating performance. A secondary purpose was to evaluate if a change in hollow shape can create additional effects on skating performance. Thirty-seven male ice hockey players (age=18 years, SD=3.4) participated. The intervention consisted of four sharpening trials assessed using three on-ice tests. Participant feedback was also assessed using a Likert scale questionnaire. Statistical analysis included within-subject repeated measures MANOVA of trial by skating variables (p≤0.05). Results revealed Contour 1 enhanced performance compared to baseline on six variables at varsity level and five variables at midget level. Contour 1 enhanced performance compared to Contour 2 on six variables at the varsity and midget levels. Contour 1 also scored highest on the feedback questionnaire. Findings of this study indicate that contouring is a necessary practice to achieve optimal skating performance.

A Struggle Against the Odds: Understanding the Lived Experiences of Canadian Hockey League (CHL) Players

The purpose of this research was to examine the experiences of Canadian Hockey League (CHL) players using a Foucauldian theory-based analysis. Specifically, this thesis contends that power relations between players and CHL hockey authorities need to be critically assessed. The CHL is the world’s leading developmental junior ice hockey league. Comprised of 1,400 hockey players, aged 15–21 years old on 60 teams through three divisions, the CHL is a primary supplier of talent for the National Hockey League. In the last year, several issues surrounding unjust practices within the CHL have been brought to the forefront, indicating that the potential for harassment, abuse, and exploitative practices are heightened in an organization such as the CHL, where profits are extracted from the labour of youth. Ultimately, this study is designed to contribute to both scholarly and public audiences, providing a critical analysis of the welfare of youth in the CHL.

Players and Avatars: The Connections between Player Personality, Avatar Personality, and Behavior in Video Games

The increasing variety and complexity of video games allows players to choose how to behave and represent themselves within these virtual environments. The focus of this dissertation was to examine the connections between the personality traits (specifically, HEXACO traits and psychopathic traits) of video game players and player-created and controlled game-characters (i.e., avatars), and the link between traits and behavior in video games. In Study 1 (n = 198), the connections between player personality traits and behavior in a Massively Multiplayer Online Roleplaying Game (World of Warcraft) were examined. Six behavior components were found (i.e., Player-versus-Player, Social Player-versus-Environment, Working, Helping, Immersion, and Core Content), and each was related to relevant personality traits. For example, Player-versus-Player behaviors were negatively related to Honesty-Humility and positively related to psychopathic traits, and Immersion behaviors (i.e., exploring, role-playing) were positively related to Openness to Experience. In Study 2 (n = 219), the connections between player personality traits and in-game behavior in video games were examined in university students. Four behavior components were found (i.e., Aggressing, Winning, Creating, and Helping), and each was related to at least one personality trait. For example, Aggressing was negatively related to Honesty-Humility and positively related to psychopathic traits. In Study 3 (n = 90), the connections between player personality traits and avatar personality traits were examined in World of Warcraft. Positive player-avatar correlations were observed for all personality traits except Extraversion. Significant mean differences between players and avatars were observed for all traits except Conscientiousness; avatars had higher mean scores on Extraversion and psychopathic traits, but lower mean scores on the remaining traits. In Study 4, the connections between player personality traits, avatar traits, and observed behaviors in a life-simulation video game (The Sims 3) were examined in university students (n = 93). Participants created two avatars and used these avatars to play The Sims 3. Results showed that the selection of certain avatar traits was related to relevant player personality traits (e.g., participants who chose the Friendly avatar trait were higher in Honesty-Humility, Emotionality, and Agreeableness, and lower in psychopathic traits). Selection of certain character-interaction behaviors was related to relevant player personality traits (e.g., participants with higher levels of psychopathic traits used more Mean and fewer Friendly interactions). Together, the results of the four studies suggest that individuals generally behave and represent themselves in video games in ways that are consistent with their real-world tendencies.