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Sample records for demands control support

  1. Job Demands-Control-Support model and employee safety performance.

    Science.gov (United States)

    Turner, Nick; Stride, Chris B; Carter, Angela J; McCaughey, Deirdre; Carroll, Anthony E

    2012-03-01

    The aim of this study was to explore whether work characteristics (job demands, job control, social support) comprising Karasek and Theorell's (1990) Job Demands-Control-Support framework predict employee safety performance (safety compliance and safety participation; Neal and Griffin, 2006). We used cross-sectional data of self-reported work characteristics and employee safety performance from 280 healthcare staff (doctors, nurses, and administrative staff) from Emergency Departments of seven hospitals in the United Kingdom. We analyzed these data using a structural equation model that simultaneously regressed safety compliance and safety participation on the main effects of each of the aforementioned work characteristics, their two-way interactions, and the three-way interaction among them, while controlling for demographic, occupational, and organizational characteristics. Social support was positively related to safety compliance, and both job control and the two-way interaction between job control and social support were positively related to safety participation. How work design is related to employee safety performance remains an important area for research and provides insight into how organizations can improve workplace safety. The current findings emphasize the importance of the co-worker in promoting both safety compliance and safety participation. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  2. Understanding well-being and learning of Nigerian nurses: a job demand control support model approach.

    Science.gov (United States)

    van Doorn, Yvonne; van Ruysseveldt, Joris; van Dam, Karen; Mistiaen, Wilhelm; Nikolova, Irina

    2016-10-01

    This study investigated whether Nigerian nurses' emotional exhaustion and active learning were predicted by job demands, control and social support. Limited research has been conducted concerning nurses' work stress in developing countries, such as Nigeria. Accordingly, it is not clear whether work interventions for improving nurses' well-being in these countries can be based on work stress models that are developed in Western countries, such as the job demand control support model, as well as on empirical findings of job demand control support research. Nurses from Nurses Across the Borders Nigeria were invited to complete an online questionnaire containing validated scales; 210 questionnaires were fully completed and analysed. Multiple regression analysis was used to test the hypotheses. Emotional exhaustion was higher for nurses who experienced high demands and low supervisor support. Active learning occurred when nurses worked under conditions of high control and high supervisor support. The findings suggest that the job demand control support model is applicable in a Nigerian nursing situation; the model indicates which occupational stressors contribute to poor well-being in Nigerian nurses and which work characteristics may boost nurses' active learning. Job (re)design interventions can enhance nurses' well-being and learning by guarding nurses' job demands, and stimulating job control and supervisor support. © 2016 John Wiley & Sons Ltd.

  3. An Experience Sampling Study of Learning, Affect, and the Demands Control Support Model

    Science.gov (United States)

    Daniels, Kevin; Boocock, Grahame; Glover, Jane; Hartley, Ruth; Holland, Julie

    2009-01-01

    The demands control support model (R. A. Karasek & T. Theorell, 1990) indicates that job control and social support enable workers to engage in problem solving. In turn, problem solving is thought to influence learning and well-being (e.g., anxious affect, activated pleasant affect). Two samples (N = 78, N = 106) provided data up to 4 times per…

  4. Family nursing hospital training and the outcome on job demands, control and support.

    Science.gov (United States)

    Sigurdardottir, Anna Olafia; Svavarsdottir, Erla Kolbrun; Juliusdottir, Sigrun

    2015-07-01

    The purpose of this study was to evaluate the impact of a family systems nursing hospital training educational program (ETI program) on nurses' and midwives' perception of job demands, control, and/or support. Of the nurses and midwives who were working in the Women's and Children's Services Division at The National University Hospital in Iceland, 479 participated in the study on three time periods from 2009 to 2011. Scores for the characteristics of job demands and job control were created to categorize participants into four job types (Karasek and Theorell, 1990). These four job types are high strain (high demand, low control), passive (low demand, low control), low strain (low demand, high control), and active (high demand, high control). However, when the data were evaluated based on the proportion of job characteristics as reported by the nurses and the midwives, no significant difference was found over time (2009 to 2011) (χ(2)=5.203, p=.518). However, based on the results from the independent t-tests at time 1, a significant difference was found amongst the high strain job group regarding perceived support from administrators and colleagues among the nurses and midwives who had taken the ETI program compared to those who had not taken the program (χ(2)=2.218, p=.034). This indicates that the health care professionals who characterized their job to be of high demand but with low control evaluated the support from their administrators and colleagues to be significantly higher if they had taken the ETI program than did the nurses and midwives who did not take the ETI program. These findings are promising because they might, in the long run, increase the nurses' and midwives' autonomy and control over their own work. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. The Very Best of the Millennium: Longitudinal Research and the Demand-Control-(Support) Model

    NARCIS (Netherlands)

    Lange, A.H.de; Taris, T.W.; Kompier, M.A.J.; Houtman, I.L.D.; Bongers, P.M.

    2003-01-01

    This study addressed the methodological quality of longitudinal research examining R. Karasek and T. Theorell's (1990) demand-control-(support) model and reviewed the results of the best of this research. Five criteria for evaluating methodological quality were used: type of design, length of time

  6. "The very best of the Millennium": Longitudinal research and the Demand-Control-(Support) model

    NARCIS (Netherlands)

    de Lange, A.H.; Taris, T.W.; Kompier, M.A.J.; Houtman, I.L.D.; Bongers, P.M.

    2003-01-01

    This study addressed the methodological quality of longitudinal research examining R. Karasek and T. Theorell's (1990) demand-control-(support) model and reviewed the results of the best of this research. Five criteria for evaluating methodological quality were used: type of design, length of time

  7. The very best of the millennium: Longitudinal research and the demands-control (-support) model

    NARCIS (Netherlands)

    Lange, A.H. de; Taris, T.W.; Kompier, M.A.J.; Houtman, I.L.D.; Bongers, P.M.

    2003-01-01

    This study addressed the methodological quality of longitudinal research examining R. Karasek and T. Theorell’s (1990) demand-control-(support) model and reviewed the results of the best of this research. Five criteria for evaluating methodological quality were used: type of design, length of time

  8. The Demand-Control-Support model and intent to leave across six European Countries

    NARCIS (Netherlands)

    Widerszal-Bazyl, Maria; Radkiewicz, Piotr; Hasselhorn, Hans Martin; Conway, Paul Maurice; van der Heijden, Beatrice

    2008-01-01

    In this paper, the explanatory power of the Demand-Control-Support (DCS) model for intent to leave (ITL) a job was tested, with employment opportunities (EO) taken into consideration. It was hypothesized that, when employment opportunities are low, the explanatory power of the DCS model for ITL is

  9. A Daily Diary Study of Coping in the Context of the Job Demands-Control-Support Model

    Science.gov (United States)

    Daniels, Kevin; Harris, Claire

    2005-01-01

    We examined one of the processes thought to underpin Karasek and Theorell's job demands-control-support model (1990). This is that control and support accentuate better well-being by fostering problem-focused coping with work demands. We also examined whether other forms of coping implemented through control and support are related to indicators…

  10. Psychosocial work environment and health in U.S. metropolitan areas: a test of the demand-control and demand-control-support models.

    Science.gov (United States)

    Muntaner, C; Schoenbach, C

    1994-01-01

    The authors use confirmatory factor analysis to investigate the psychosocial dimensions of work environments relevant to health outcomes, in a representative sample of five U.S. metropolitan areas. Through an aggregated inference system, scales from Schwartz and associates' job scoring system and from the Dictionary of Occupational Titles (DOT) were employed to examine two alternative models: the demand-control model of Karasek and Theorell and Johnson's demand-control-support model. Confirmatory factor analysis was used to test the two models. The two multidimensional models yielded better fits than an unstructured model. After allowing for the measurement error variance due to the method of assessment (Schwartz and associates' system or DOT), both models yielded acceptable goodness-of-fit indices, but the fit of the demand-control-support model was significantly better. Overall these results indicate that the dimensions of Control (substantive complexity of work, skill discretion, decision authority), Demands (physical exertion, physical demands and hazards), and Social Support (coworker and supervisor social supports) provide an acceptable account of the psychosocial dimensions of work associated with health outcomes.

  11. Dimensional structure of the demand control support questionnaire: a Brazilian context.

    Science.gov (United States)

    Hökerberg, Yara Hahr Marques; Aguiar, Odaleia Barbosa; Reichenheim, Michael; Faerstein, Eduardo; Valente, Joaquim Gonçalves; Fonseca, Maria de Jesus; Passos, Sonia Regina Lambert

    2010-04-01

    According to Karasek, job strain results from an interaction between high demands and low decision latitude. To reassess the dimensional structure and evaluate the internal consistency of demand control support questionnaire (DCSQ), a shortened version of job content questionnaire that was not sufficiently evaluated in validation studies. The study investigated 825 workers who completed the DCSQ in Rio de Janeiro, Brazil; to 399 workers, the questionnaire was self-administered at a hospital (2004-2005), and 426 workers were interviewed at nine restaurants (2006-2007). Confirmatory factor analysis using structural equation models was used to test theoretical structure of dimensionality. Internal consistency was evaluated by composite reliability and convergent validity by average variance extracted. Confirmatory factor analysis supported the instrument in three dimensions: demands, skill discretion and decision authority. The best fit model was achieved by removing social support at work and the item repetitive work (skill discretion). A cross-loading from learning new things on demands and an error measurement correlation between work fast and work intense were confirmed. Composite reliability was acceptable for all dimensions, except for demands (0.58), which also showed inadequate average variance extracted (0.32). This final model was confirmed in separate analyses according to work setting, but the loadings of demands were lower for restaurant workers. Our results indicated that skill discretion and decision authority formed two distinct dimensions. Additionally, the item repetitive work should be removed, as well as one of the items work fast or work intense (demands). Future research is still required to confirm these findings.

  12. Interaction between demand-control and social support in the occurrence of common mental disorders

    Directory of Open Access Journals (Sweden)

    Amália Ivine Santana Mattos

    Full Text Available ABSTRACT OBJECTIVE To analyze the interaction between the psychosocial aspects of work and the occurrence of common mental disorders among health workers. METHODS This is a cross-sectional study conducted with a representative sample of workers of the primary health care of five municipalities of the State of Bahia, Brazil, in 2012. The variable of outcome were the common mental disorders evaluated by the SRQ-20, and the variables of exposure were high demand (high psychological demand and low control over the work and low social support in the workplace. Interaction was checked by the deviation of the additivity of the effects for the factors studied from the calculation of excess risk from interaction, proportion of cases attributed to interaction, and the synergy index. RESULTS The global prevalence of common mental disorders was 21%. The group of combined exposure has shown higher magnitude (high demand and low social support, reaching 28% when compared to the 17% in the situation of no exposure (low demand and high social support. CONCLUSIONS The results strengthen the hypothesis of interaction between the factors investigated, directing to the synergy of the effects.

  13. Cross-lagged relationships between workplace demands, control, support, and sleep problems.

    Science.gov (United States)

    Hanson, Linda L Magnusson; Åkerstedt, Torbjörn; Näswall, Katharina; Leineweber, Constanze; Theorell, Töres; Westerlund, Hugo

    2011-10-01

    Sleep problems are experienced by a large part of the population. Work characteristics are potential determinants, but limited longitudinal evidence is available to date, and reverse causation is a plausible alternative. This study examines longitudinal, bidirectional relationships between work characteristics and sleep problems. Prospective cohort/two-wave panel. Sweden. 3065 working men and women approximately representative of the Swedish workforce who responded to the 2006 and 2008 waves of the Swedish Longitudinal Occupational Survey of Health (SLOSH). N/A. Bidirectional relationships between, on the one hand, workplace demands, decision authority, and support, and, on the other hand, sleep disturbances (reflecting lack of sleep continuity) and awakening problems (reflecting feelings of being insufficiently restored), were investigated by structural equation modeling. All factors were modeled as latent variables and adjusted for gender, age, marital status, education, alcohol consumption, and job change. Concerning sleep disturbances, the best fitting models were the "forward" causal model for demands and the "reverse" causal model for support. Regarding awakening problems, reciprocal models fitted the data best. Cross-lagged analyses indicates a weak relationship between demands at Time 1 and sleep disturbances at Time 2, a "reverse" relationship from support T1 to sleep disturbances T2, and bidirectional associations between work characteristics and awakening problems. In contrast to an earlier study on demands, control, sleep quality, and fatigue, this study suggests reverse and reciprocal in addition to the commonly hypothesized causal relationships between work characteristics and sleep problems based on a 2-year time lag.

  14. Interactive associations of parental support, demands, and psychological control, over adolescents' beliefs about the legitimacy of parental authority.

    Science.gov (United States)

    Mellado, Carlos; Cumsille, Patricio; Martínez, M Loreto

    2018-04-01

    The present study examined the relationship between parental support, demand, psychological control and adolescents' beliefs about the legitimacy of parental authority for personal and multifaceted issues in a sample of 1342 Chilean adolescents (M = 16.38, SD = 1.24, age range 14-20). Results from multiple regression analyses separated by age indicated that demand was positively associated with adolescents' beliefs about the legitimacy of parental authority for personal and multifaceted issues and that psychological control was negatively associated with adolescents' legitimacy beliefs concerning personal issues. Furthermore, parental support moderated the relationship between parental demand and adolescents' beliefs about parental legitimacy for personal and multifaceted issues: those who display high levels of demand showed stronger beliefs about parental legitimacy at high level of support. These results support the interactive effect of parental support and demand on adolescent development. Copyright © 2018. Published by Elsevier Ltd.

  15. Interaction between demand-control and social support in the occurrence of common mental disorders.

    Science.gov (United States)

    Mattos, Amália Ivine Santana; Araújo, Tânia Maria de; Almeida, Maura Maria Guimarães de

    2017-05-15

    To analyze the interaction between the psychosocial aspects of work and the occurrence of common mental disorders among health workers. This is a cross-sectional study conducted with a representative sample of workers of the primary health care of five municipalities of the State of Bahia, Brazil, in 2012. The variable of outcome were the common mental disorders evaluated by the SRQ-20, and the variables of exposure were high demand (high psychological demand and low control over the work) and low social support in the workplace. Interaction was checked by the deviation of the additivity of the effects for the factors studied from the calculation of excess risk from interaction, proportion of cases attributed to interaction, and the synergy index. The global prevalence of common mental disorders was 21%. The group of combined exposure has shown higher magnitude (high demand and low social support), reaching 28% when compared to the 17% in the situation of no exposure (low demand and high social support). The results strengthen the hypothesis of interaction between the factors investigated, directing to the synergy of the effects. Analisar a interação entre aspectos psicossociais do trabalho e a ocorrência de transtornos mentais comuns entre trabalhadores da saúde. Estudo transversal conduzido em amostra representativa de trabalhadores da atenção básica de cinco municípios da Bahia em 2012. As variáveis desfecho foram os transtornos mentais comuns avaliados pelo SRQ-20, as de exposição foram a alta exigência (alta demanda psicológica e baixo controle sobre o próprio trabalho) e o baixo apoio social no trabalho. A interação foi verificada pelo afastamento da aditividade dos efeitos para fatores estudados a partir do cálculo do excesso de risco devido à interação, proporção de casos atribuída à interação e índice de sinergia. A prevalência global de transtornos mentais comuns foi de 21%. Apresentou maior magnitude no grupo de exposi

  16. The Effect of Job Demand-Control-Social Support Model on Nurses' Job Satisfaction in Specialized Teaching Hospitals, Ethiopia

    OpenAIRE

    Negussie, Nebiat; Kaur, Geetinder

    2016-01-01

    Background The job demand-control-social support model has been widely studied in western countries but has not been theoretically addressed on health workers of sub-Saharan African countries. Therefore, this study investigates the relationship between Job Demand-Control-Support Model and job satisfaction in specialized teaching hospitals in Ethiopia. Method A cross-sectional survey was conducted from September 2014 to May 2015 in three public specialized teaching hospitals in Ethiopia. Among...

  17. An Analysis of Decentralized Demand Response as Frequency Control Support under CriticalWind Power Oscillations

    Directory of Open Access Journals (Sweden)

    Jorge Villena

    2015-11-01

    Full Text Available In power systems with high wind energy penetration, the conjunction of wind power fluctuations and power system inertia reduction can lead to large frequency excursions, where the operating reserves of conventional power generation may be insufficient to restore the power balance. With the aim of evaluating the demand-side contribution to frequency control, a complete process to determine critical wind oscillations in power systems with high wind penetration is discussed and described in this paper. This process implies thousands of wind power series simulations, which have been carried out through a validated offshore wind farm model. A large number of different conditions have been taken into account, such as frequency dead bands, the percentages of controllable demand and seasonal factor influence on controllable loads. Relevant results and statistics are also included in the paper.

  18. Do high job demands increase intrinsic motivation or fatigue or both? The role of job control and job social support

    NARCIS (Netherlands)

    Van Yperen, N.W.; Hagedoorn, M.

    2003-01-01

    Examined whether job control and job social support reduce signs of fatigue and enhance intrinsic motivation among employees facing high job demands. 555 nurses (mean age 35.5 yrs) working at specialized units for patients with different levels of mental deficiency completed surveys regarding: (1)

  19. Job characteristics and safety climate: the role of effort-reward and demand-control-support models.

    Science.gov (United States)

    Phipps, Denham L; Malley, Christine; Ashcroft, Darren M

    2012-07-01

    While safety climate is widely recognized as a key influence on organizational safety, there remain questions about the nature of its antecedents. One potential influence on safety climate is job characteristics (that is, psychosocial features of the work environment). This study investigated the relationship between two job characteristics models--demand-control-support (Karasek & Theorell, 1990) and effort-reward imbalance (Siegrist, 1996)--and safety climate. A survey was conducted with a random sample of 860 British retail pharmacists, using the job contents questionnaire (JCQ), effort-reward imbalance indicator (ERI) and a measure of safety climate in pharmacies. Multivariate data analyses found that: (a) both models contributed to the prediction of safety climate ratings, with the demand-control-support model making the largest contribution; (b) there were some interactions between demand, control and support from the JCQ in the prediction of safety climate scores. The latter finding suggests the presence of "active learning" with respect to safety improvement in high demand, high control settings. The findings provide further insight into the ways in which job characteristics relate to safety, both individually and at an aggregated level.

  20. Demand as Frequency Controlled Reserve

    DEFF Research Database (Denmark)

    Xu, Zhao; Togeby, Mikael; Østergaard, Jacob

    This report summaries the research outcomes of the project ‘Demand as Frequency Controlled Reserve (DFR)’, which has received the support from Energinet.dk’s PSO program, Grant no. 2005-2-6380. The objective of this project is to investigate the technology of using electricity demands for providing...

  1. Social support and its interrelationships with demand-control model factors on presenteeism and absenteeism in Japanese civil servants.

    Science.gov (United States)

    Saijo, Yasuaki; Yoshioka, Eiji; Nakagi, Yoshihiko; Kawanishi, Yasuyuki; Hanley, Sharon J B; Yoshida, Takahiko

    2017-08-01

    To elucidate the impact of social support and its interrelations with other demand-control-support (DCS) model factors on presenteeism and absenteeism, and to determine which DCS factors were most influential. Questionnaires from 2535 local government employees were analyzed. The Brief Job Stress Questionnaire (BJSQ) was used to assess DCS factors including job demand, job control, and social support from supervisors and coworkers. The Stanford Presenteeism Scale 13-item version (SPS-13) was used to evaluate both absenteeism (absent days) and presenteeism. For the latter, the Work Impairment Score (WIS) and the Work Output Score (WOS) were also used. Possible confounder-adjusted logistic and negative binomial regression analyses were performed to obtain odds ratios (ORs) for WIS and WOS and relative risks (RRs) for absenteeism according to DCS factors. Higher job control had a significantly protective effect on higher WIS in both males and females and a lower WOS in males. Based on a point estimate of an OR per 1 standard deviation change of each DCS factor, job control had the strongest effect on higher WIS in both males and females and a lower WOS in males. Higher job demand resulted in significantly higher ORs for both male and female WIS, and a lower WOS in females. Support from supervisors had a significantly protective effect on higher WIS in females and a lower WOS in males. Support from coworkers had a significantly protective effect on higher WIS in males. Higher support from coworkers had a significantly protective effect on absenteeism among both males and females, and higher job control had a significantly protective effect in females. The combination of high job strain and low support from supervisors had a significantly worsening effect, except for absenteeism in females. High job strain and low support from coworkers had a significantly worsening effect except for WOS in males. The results suggest job control was the DCS factor most related to

  2. Managerial leadership is associated with employee stress, health, and sickness absence independently of the demand-control-support model.

    Science.gov (United States)

    Westerlund, Hugo; Nyberg, Anna; Bernin, Peggy; Hyde, Martin; Oxenstierna, Gabriel; Jäppinen, Paavo; Väänänen, Ari; Theorell, Töres

    2010-01-01

    Research on health effects of managerial leadership has only taken established work environment factors into account to a limited extent. We therefore investigated the associations between a measure of Attentive Managerial Leadership (AML), and perceived stress, age-relative self-rated health, and sickness absence due to overstrain/fatigue, adjusting for the dimensions of the Demand-Control-Support model. Blue- and white-collar workers from Finland, Germany and Sweden employed in a multi-national forest industry company (N=12,622). Cross-sectional data on leadership and health from a company-wide survey analysed with logistic regression in different subgroups. AML was associated with perceived stress, age-relative self-rated health, and sickness absence due to overstrain/fatigue after controlling for the Demand-Control-Support model. Lack of AML was significantly associated with a high stress level in all subgroups (OR=1.68-2.67). Associations with age-relative self-rated health and sickness absence due to overstrain/fatigue were weaker, but still significant, and in the expected direction for several of the subgroups studied, suggesting an association between lack of AML and negative health consequences. The study indicates that managerial leadership is associated with employee stress, health, and sickness absence independently of the Demand-Control-Support model and should be considered in future studies of health consequences for employees, and in work environment interventions.

  3. The importance of genetic and shared environmental factors for the associations between job demands, control, support and burnout.

    Directory of Open Access Journals (Sweden)

    Victoria Blom

    Full Text Available Within occupational health research, one of the most influential models is the Job Demands-Control-Support model. Numerous studies have applied the model to different domains, with both physical and psychological health outcomes, such as burnout. The twin design provides a unique and powerful research methodology for examining the effects of environmental risk factors on burnout while taking familial factors (genetic and shared environment into account. The aim of the present study was to investigate the impact of familial factors on the associations of burnout with job demands, control and support. A total of 14,516 individuals from the Swedish Twin Registry, who were born between 1959 and 1986, and who participated in the Study of Twin Adults: Genes and Environment (STAGE by responding to a web-based questionnaire in 2005, were included in the analyses. Of these, there were 5108 individuals in complete same-sex twin pairs. Co-twin control analyses were performed using linear mixed modeling, comparing between-pairs effects and within-pair effects, stratified also by zygosity and sex. The results indicate that familial factors are of importance in the association between support and burnout in both women and men, but not between job demands and burnout. There are also tendencies towards familial factors being involved in the association between control and burnout in men. These results offer increased understanding of the mechanisms involved in the associations between work stress and burnout.

  4. Directive and nondirective social support in the workplace - is this social support distinction important for subjective health complaints, job satisfaction, and perception of job demands and job control?

    Science.gov (United States)

    Johnsen, Tone Langjordet; Eriksen, Hege Randi; Indahl, Aage; Tveito, Torill Helene

    2018-05-01

    Social support is associated with well-being and positive health outcomes. However, positive outcomes of social support might be more dependent on the way support is provided than the amount of support received. A distinction can be made between directive social support, where the provider resumes responsibility, and nondirective social support, where the receiver has the control. This study examined the relationship between directive and nondirective social support, and subjective health complaints, job satisfaction and perception of job demands and job control. A survey was conducted among 957 Norwegian employees, working in 114 private kindergartens (mean age 40.7 years, SD = 10.5, 92.8% female), as part of a randomized controlled trial. This study used only baseline data. A factor analysis of the Norwegian version of the Social Support Inventory was conducted, identifying two factors: nondirective and directive social support. Hierarchical regression analyses were then performed. Nondirective social support was related to fewer musculoskeletal and pseudoneurological complaints, higher job satisfaction, and the perception of lower job demands and higher job control. Directive social support had the opposite relationship, but was not statistically significant for pseudoneurological complaints. It appears that for social support to be positively related with job characteristics and subjective health complaints, it has to be nondirective. Directive social support was not only without any association, but had a significant negative relationship with several of the variables. Nondirective social support may be an important factor to consider when aiming to improve the psychosocial work environment. Clinicaltrials.gov: NCT02396797. Registered 23 March 2015.

  5. Beyond the job demand control (-support) model : explaining stress reactions in nurses

    NARCIS (Netherlands)

    Pisanti, Renato

    2012-01-01

    Nurses have been identified as having a risk of experiencing stress and burnout. The nature and organization of the job make nursing inherently difficult. Research highlights that occupational stress is largely dependent on psychosocial job characteristics, such as job demands and job resources. The

  6. Job demands-control-social support model and coping strategies: predicting burnout and wellbeing in a group of Italian nurses.

    Science.gov (United States)

    Pisanti, R

    2012-01-01

    Nursing is generally considered to be a stressful profession. The purpose of the present study was to test the core hypotheses of the job demands-control-social support model (JDCS) of Karasek & Theorell (1990). In order to refine and extend the JDCS model, we also analyzed the direct and interactive role of three coping strategies: task- oriented, emotion-oriented, and avoidance-oriented coping. Questionnaire data from 1383 nurses (77%female) were collected. Controlling for demographic variables and non-linearity of the associations between job characteristics and outcomes (job satisfaction; burnout dimensions, psychological distress, and somatic complaints), hierarchical regression analyses indicated that job control and social support combined additively (p < 0.001) with job demands to explain the wellbeing outcomes (explained variance between 6% and 28%). Coping strategies accounted for additional variance (p < 0.001; explained variance between 4% and 15%) in all outcomes except in job satisfaction. Support was found for main effects of coping. Coping strategies did not moderate the impact of job characteristics on burnout and wellbeing. Emotion-oriented coping emerged as the most important predictor and was consistently associated with higher burnout levels and lower wellbeing levels. The results demonstrated the need to include the role of individual variables in the JDCS model. The limitations of the study, and theoretical and practical implications are discussed.

  7. The Influence of Recognition and Social Support on European Health Professionals' Occupational Stress: A Demands-Control-Social Support-Recognition Bayesian Network Model.

    Science.gov (United States)

    García-Herrero, Susana; Lopez-Garcia, Jose R; Herrera, Sixto; Fontaneda, Ignacio; Báscones, Sonia Muñoz; Mariscal, Miguel A

    2017-01-01

    Healthcare professionals undergo high levels of occupational stress as a result of their working conditions. Thus, the aim of this study is to develop a model that focuses on healthcare professionals so as to analyze the influence that job demands, control, social support, and recognition have on the likelihood that a worker will experience stress. The data collected correspond to 2,211 healthcare workers from 35 countries, as reported in the sixth European Working Condition Survey (EWCS). The results obtained from this study allow us to infer stress under several working condition scenarios and to identify the more relevant variables in order to reduce this stress in healthcare professionals, which is of paramount importance to managing the stress of workers in this sector. The Bayesian network proposed indicates that emotional demands have a greater influence on raising the likelihood of stress due to workload than do family demands. The results show that the support of colleagues, in general, has less effect on reducing stress than social support from superiors. Furthermore, the sensitivity analysis shows that, in high-demand and low-control situations, recognition clearly impacts stress, drastically reducing it.

  8. Cholgate - a randomized controlled trial comparing the effect of automated and on-demand decision support on the management of cardiovascular disease factors in primary care

    NARCIS (Netherlands)

    J.T. van Wyk (Jacobus); M.A.M. van Wijk (Marc); P.W. Moorman (Peter); M. Mosseveld (Mees); J. van der Lei (Johan)

    2003-01-01

    textabstractAutomated and on-demand decision support systems integrated into an electronic medical record have proven to be an effective implementation strategy for guidelines. Cholgate is a randomized controlled trial comparing the effect of automated and on-demand decision

  9. Job-Demands, Job Control, Social Support, Self-Efficacy, and Burnout of Staff of Residential Children's Homes

    Science.gov (United States)

    Brouwers, André; Tomic, Welko

    2016-01-01

    The aim of the current study was to examine among educational staff members of residential children's homes to what extent task demands, job control, emotional and social support from colleagues and management as well as self-efficacy beliefs concerning coping with aggressive behaviour in youngsters are associated with emotional exhaustion,…

  10. Incorporation of Emotional Labor in the Demand-Control-Support Model: The relation with Emotional Exhaustion and Personal Accomplishment in Nurses

    NARCIS (Netherlands)

    Näring, Gérard; van Droffelaar, Annemarie

    2008-01-01

    Nursing comprises interactions with patients which may require emotional labor. This study clarifies the relation of emotional labor with the three burnout dimensions within the context of the Demand Control Support model in nurses. We used the Dutch Questionnaire on Emotional Labor (D-QEL) to

  11. Voltage Controlled Dynamic Demand Response

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    Future power system is expected to be characterized by increased penetration of intermittent sources. Random and rapid fluctuations in demands together with intermittency in generation impose new challenges for power balancing in the existing system. Conventional techniques of balancing by large...... central or dispersed generations might not be sufficient for future scenario. One of the effective methods to cope with this scenario is to enable demand response. This paper proposes a dynamic voltage regulation based demand response technique to be applied in low voltage (LV) distribution feeders....... An adaptive dynamic model has been developed to determine composite voltage dependency of an aggregated load on feeder level. Following the demand dispatch or control signal, optimum voltage setting at the LV substation is determined based on the voltage dependency of the load. Furthermore, a new technique...

  12. Demand as Frequency Controlled Reserve

    DEFF Research Database (Denmark)

    Xu, Zhao; Østergaard, Jacob; Togeby, Mikael

    2011-01-01

    Relying on generation side alone is deemed insufficient to fulfill the system balancing needs for future Danish power system, where a 50% wind penetration is outlined by the government for year 2025. This paper investigates using the electricity demand as frequency controlled reserve (DFR) as a new...... balancing measure, which has a high potential and can provide many advantages. Firstly, the background of the research is reviewed, including conventional power system reserves and the electricity demand side potentials. Subsequently, the control logics and corresponding design considerations for the DFR...

  13. Demand controlled ventilation; Behovsstyrt ventilasjon

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Henning Holm

    2006-07-01

    The terms CAV and VAV have been known terms for many years in the ventilation business. The terms are also included in building regulations, but the time is now right to focus on demand controlled ventilation (DCV). The new building regulations and the accompanying energy framework underline the need for a more nuanced thinking when it comes to controlling ventilation systems. Descriptions and further details of the ventilation systems are provided (ml)

  14. Demand Controlled Ventilation and Classroom Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-05-01

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

  15. Demand controlled ventilation and classroom ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-06

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

  16. Demand as frequency controlled reserve

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Togeby, M.; OEstergaard, J.

    2008-09-15

    Using demand as frequency controlled reserve (DFR) is an emerging technology which allow demand to participate actively in maintaining the system operation without reducing the energy service delivered to the customer and without need of user interaction. The basic premise is that traditional frequency controlled reserves from power plants and interconnections with neighbouring systems can be costly, slow and not fulfil the need for future power grids with a high share of wind power and fewer central power plants, and an intention to perform flexible operation such as is landing. Electricity demands, on the other hand, have advantages as frequency reserve including fast activation speed, smooth linear activation, low expected costs, and well-dispersed in the distribution grid. The main challenge of DFR is new methods for monitoring the available capacity. This project has investigated the technology of using electricity demands for providing frequency reserve to power systems. Within the project the potential and economy of DFR compatible loads in Denmark has been investigated, control logic has been designed, power system impact has been investigated, potential business models has been evaluated and an implementation strategy has been suggested. The tasks and goals of the project have been successfully accomplished based on which the conclusion and future recommendation are made. This project has developed the DFR technology that enables electricity demands to autonomously disconnect or reconnect to the grid in response to system frequency variations. The developed DFR technology is proved to be a promising technology from several perspectives. Technically, using DFR is feasible to provide reserves and enhance power system frequency control, while fulfilling technical requirements such as linear activation (or reconnection) according to frequency (or time). Environmentally, the DFR technology is pollution free in contrast to traditional reserves from generation

  17. Factor structure and longitudinal measurement invariance of the demand control support model: an evidence from the Swedish Longitudinal Occupational Survey of Health (SLOSH).

    Science.gov (United States)

    Chungkham, Holendro Singh; Ingre, Michael; Karasek, Robert; Westerlund, Hugo; Theorell, Töres

    2013-01-01

    To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes.

  18. Factor structure and longitudinal measurement invariance of the demand control support model: an evidence from the Swedish Longitudinal Occupational Survey of Health (SLOSH.

    Directory of Open Access Journals (Sweden)

    Holendro Singh Chungkham

    Full Text Available OBJECTIVES: To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ, using the Swedish Longitudinal Occupational Survey of Health (SLOSH. METHODS: A confirmatory factor analysis (CFA and multi-group confirmatory factor analysis (MGCFA models within the framework of structural equation modeling (SEM have been used to examine the factor structure and invariance across time. RESULTS: Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42 between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68. The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. CONCLUSION: Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes.

  19. Controlling energy demand. What history?

    International Nuclear Information System (INIS)

    Beers, Marloes; Bonhomme, Noel; Bouvier, Yves; Pautard, Eric; Fevrier, Patrick; Lanthier, Pierre; Goyens, Valerie; Desama, Claude; Beltran, Alain

    2012-01-01

    this special dossier of the historical annals of electricity collection takes stock of the post 1970's history of energy demand control in industrialized countries: Abatement of energy dependence, the European Communities program of rational use of energy in the 1970's (Marloes Beers); The G7 and the energy cost: the limits of dialogue between industrialized countries - 1975-1985 (Noel Bonhomme); Saving more to consume more. The ambiguity of EDF's communication during the 'energy saving' era (Yves Bouvier); From rationing to energy saving certificates, 4 decades of electricity demand control in France and in the UK (eric Pautard); The French agency of environment and energy mastery (ADEME): between energy control and sustainable development (Patrick Fevrier); Hydro-Quebec and efficiency in household energy consumption, from 1990 to the present day (Pierre Lanthier); Control of energy consumption since the 1970's, the policy of rational use of energy in Walloon region - Belgium (Valerie Goyens); Electricity distribution in the new energy paradigm (Claude Desama); Conclusion (Alain Beltran)

  20. Directive and nondirective social support in the workplace – is this social support distinction important for subjective health complaints, job satisfaction, and perception of job demands and job control?

    Science.gov (United States)

    Johnsen, Tone Langjordet; Eriksen, Hege Randi; Indahl, Aage; Tveito, Torill Helene

    2017-01-01

    Aims: Social support is associated with well-being and positive health outcomes. However, positive outcomes of social support might be more dependent on the way support is provided than the amount of support received. A distinction can be made between directive social support, where the provider resumes responsibility, and nondirective social support, where the receiver has the control. This study examined the relationship between directive and nondirective social support, and subjective health complaints, job satisfaction and perception of job demands and job control. Methods: A survey was conducted among 957 Norwegian employees, working in 114 private kindergartens (mean age 40.7 years, SD = 10.5, 92.8% female), as part of a randomized controlled trial. This study used only baseline data. A factor analysis of the Norwegian version of the Social Support Inventory was conducted, identifying two factors: nondirective and directive social support. Hierarchical regression analyses were then performed. Results: Nondirective social support was related to fewer musculoskeletal and pseudoneurological complaints, higher job satisfaction, and the perception of lower job demands and higher job control. Directive social support had the opposite relationship, but was not statistically significant for pseudoneurological complaints. Conclusions: It appears that for social support to be positively related with job characteristics and subjective health complaints, it has to be nondirective. Directive social support was not only without any association, but had a significant negative relationship with several of the variables. Nondirective social support may be an important factor to consider when aiming to improve the psychosocial work environment. Trial registration: Clinicaltrials.gov: NCT02396797. Registered 23 March 2015. PMID:28820017

  1. Do psychological job demands, decision control and social support predictreturn to work three months after a return-to-work (RTW) programme? The rapid-RTW cohort study.

    Science.gov (United States)

    Haveraaen, Lise A; Skarpaas, Lisebet S; Berg, John E; Aas, Randi W

    2015-01-01

    Long-term sickness absence is a considerable health and economic problem in the industrialised world. Factors that might predict return to work (RTW) are therefore of interest. To examine the impact of psychosocial work characteristics on RTW three months after the end of a RTW programme. A cohort study of 251 sick-listed employees from 40 different treatment and rehabilitation services in Norway recruited from February to December 2012. The Job Content Questionnaire was used to gather information on the psychosocial work conditions. Full or partial RTW was measured three months after the end of the RTW programme, using data from the national sickness absence register. Logistic regression analyses were performed to investigate the association between the psychosocial work characteristics and RTW. Having low psychological job demands (OR = 0.4, 95% CI: 0.2-0.9), high co-worker- (OR = 3.4, 95% CI: 1.5-5.8), and supervisor support (OR = 3.4, 95% CI: 1.6-7.3), and being in a low-strain job (low job demands and high control) (OR = 4.6, 95% CI: 1.1-18.6) were predictive of being in work three months after the end of the RTW programme, after adjusting for several potential prognostic factors. Interventions aimed at returning people to work might benefit from putting more emphasise on psychosocial work characteristics in the future.

  2. Cut Electric Bills by Controlling Demand

    Science.gov (United States)

    Grumman, David L.

    1974-01-01

    Electric bills can be reduced by lowering electric consumption and by controlling demand -- the amount of electricity used at a certain point in time. Gives tips to help reduce electric demand at peak power periods. (Author/DN)

  3. Demand controlled ventilation in a bathroom

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Nielsen, Toke Rammer; Topp, Claus

    2008-01-01

    consumption during periods where the demand for ventilation is low and poor indoor climate during periods where the demand for ventilation is high. Controlling the ventilation rate by demand can improve the energy performance of the ventilation system and the indoor climate. This paper compares the indoor...... climate and energy consumption of a Constant Air Volume (CAV) system and a Demand Controlled Ventilation (DCV) system for two different bathroom designs. The air change rate of the CAV system corresponded to 0.5h-1. The ventilation rate of the DCV system was controlled by occupancy and by the relative...

  4. Support Resources Demand Parameters - Aircraft. Revision A

    Science.gov (United States)

    1980-01-15

    Maintenance Squadron A- ST Advance Medium STOL Transport APU Auxillary Power Unit ASSY Assembly ATC Air Training Command AVG Average BAC Boeing Aerospace...entire study that will result in an organized and prioritized body of decision criteria and parameters that may be used by logistics managers, supervisors...technicians, and other decision makers in the process of predicting resource demand rates for operational and new emerging aircraft weapon systems

  5. Inventory control in case of unknown demand and control parameters

    NARCIS (Netherlands)

    Janssen, E.

    2010-01-01

    This thesis deals with unknown demand and control parameters in inventory control. Inventory control involves decisions on what to order when and in what quantity. These decisions are based on information about the demand. Models are constructed using complete demand information; these models ensure

  6. Employees' eldercare demands, strain, and perceived support

    NARCIS (Netherlands)

    Zacher, Hannes; Schulz, Heiko

    2015-01-01

    Purpose - In many countries, both the number of older people in need of care and the number of employed caregivers of elderly relatives will increase over the next decades. The purpose of this paper is to examine the extent to which perceived organizational, supervisor, and coworker support for

  7. Bandwidth-on-demand motion control

    NARCIS (Netherlands)

    Van Loon, S.J.L.M.; Hunnekens, B.G.B.; Simon, A.S.; van de Wouw, N.; Heemels, W.P.M.H.

    2018-01-01

    In this brief, we introduce a 'bandwidth-on-demand' variable-gain control (VGC) strategy that allows for a varying bandwidth of the feedback controller. The proposed VGC can achieve improved performance given time-varying, reference-dependent performance requirements compared with linear

  8. Demand-controlling marketing of electric utilities

    Energy Technology Data Exchange (ETDEWEB)

    Raffee, H; Fritz, W

    1980-01-01

    In situations like the shortage of energy resources the particular autonomy of the users concerning energy demand raises more and more aggravating problems for the electric utilities (EU) and, last not least, for society (i.e. the peak-load problem, threatening bottlenecks in the supply situation). Thus the requirement for a demand-controlling marketing strategy of the EU with the help of which the individual demand should be influenced in the following manner is legitimate. The article discusses the targets, strategies, and instruments of marketing performed by the EU under the aspect of their efficiency concerning demand control. The discussion leads to e.g. the following results: that a marketing strategy for the sensible, responsible, and efficent use of energy, in the long-term, serves both the interests of the users and the interests of the EU; that such a marketing programme can have the required controlling effects especially with the help of strategies like market segmentation and cooperation. The discussion makes also clear that a demand-controlling marketing strategy of the EU can hardly be realized without a considerable change within the organization of the EU on one hand and, on the other, without expanding the marketing programme toward a marketing strategy of balance.

  9. Supply-demand controls the futures

    International Nuclear Information System (INIS)

    Brown, D.

    1991-01-01

    This paper briefly discusses the futures market of petroleum and explains how futures operate. The purpose of the paper is to demonstrate that oil futures markets does no determine energy prices - it merely reflects the prices recorded through trades made in an open marketplace. A futures contract is an agreement between a buyer and a seller at a price that seems fair to both. High demand from buyers can push prices up; low demand or a willingness to sell pushes prices down. As a result, supply and demand control the futures exchange and not vice-versa. The paper goes on to explain some basic principals of the futures market including the differences between hedging and speculating on prices and marketing strategy

  10. Demand as Frequency-controlled Reserve

    DEFF Research Database (Denmark)

    Bang, Christian; Rasmussen, Christian Brandt; Østergaard, Jacob

    with great enthusiasm from all DFR project members who have shown a memorable dedication to their work. Active control of electricity demand is a key technology when creating a more dynamic, wind power friendly energy system. In this demonstration project, we have developed and tested devices, which use...... electric loads to provide frequency controlled primary reserves. The devices collected data from domestic households and industrial loads covering i.e. circulation pumps, electrical domestic heating, bottle coolers, a wastewater treatment plant etc., that have been analysed and used for the papers...

  11. Indirect control of flexible demand for power system applications

    DEFF Research Database (Denmark)

    Sossan, Fabrizio

    This thesis addresses the topic of control of flexible demand to provide support to the operation of the electric power system. We focus on the indirect control approach, a framework that enables demand response by means of a consumption incentive signal. Initially, the concept of flexibility...... a shift in the consumption according to an indirect control signal. We present from simple control algorithms with a few requirements up to model predictive control strategies. The performance of the indirect control algorithms are compared by means of hardware-in-the-loop simulations using Power...... and storage in the operation of the future power system, we develop a model predictive control strategy for a smart building with the objective of supplying iii space heating and providing regulating power to the grid according to a dynamic electricity price. We named this application energy replacement...

  12. Coal demand prediction based on a support vector machine model

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Cun-liang; Wu, Hai-shan; Gong, Dun-wei [China University of Mining & Technology, Xuzhou (China). School of Information and Electronic Engineering

    2007-01-15

    A forecasting model for coal demand of China using a support vector regression was constructed. With the selected embedding dimension, the output vectors and input vectors were constructed based on the coal demand of China from 1980 to 2002. After compared with lineal kernel and Sigmoid kernel, a radial basis function(RBF) was adopted as the kernel function. By analyzing the relationship between the error margin of prediction and the model parameters, the proper parameters were chosen. The support vector machines (SVM) model with multi-input and single output was proposed. Compared the predictor based on RBF neural networks with test datasets, the results show that the SVM predictor has higher precision and greater generalization ability. In the end, the coal demand from 2003 to 2006 is accurately forecasted. l0 refs., 2 figs., 4 tabs.

  13. Sensor-based demand controlled ventilation

    Energy Technology Data Exchange (ETDEWEB)

    De Almeida, A.T. [Universidade de Coimbra (Portugal). Dep. Eng. Electrotecnica; Fisk, W.J. [Lawrence Berkeley National Lab., CA (United States)

    1997-07-01

    In most buildings, occupancy and indoor pollutant emission rates vary with time. With sensor-based demand-controlled ventilation (SBDCV), the rate of ventilation (i.e., rate of outside air supply) also varies with time to compensate for the changes in pollutant generation. In other words, SBDCV involves the application of sensing, feedback and control to modulate ventilation. Compared to ventilation without feedback, SBDCV offers two potential advantages: (1) better control of indoor pollutant concentrations; and (2) lower energy use and peak energy demand. SBDCV has the potential to improve indoor air quality by increasing the rate of ventilation when indoor pollutant generation rates are high and occupants are present. SBDCV can also save energy by decreasing the rate of ventilation when indoor pollutant generation rates are low or occupants are absent. After providing background information on indoor air quality and ventilation, this report provides a relatively comprehensive discussion of SBDCV. Topics covered in the report include basic principles of SBDCV, sensor technologies, technologies for controlling air flow rates, case studies of SBDCV, application of SBDCV to laboratory buildings, and research needs. SBDCV appears to be an increasingly attractive technology option. Based on the review of literature and theoretical considerations, the application of SBDCV has the potential to be cost-effective in applications with the following characteristics: (a) a single or small number of dominant pollutants, so that ventilation sufficient to control the concentration of the dominant pollutants provides effective control of all other pollutants; (b) large buildings or rooms with unpredictable temporally variable occupancy or pollutant emission; and (c) climates with high heating or cooling loads or locations with expensive energy.

  14. Electric Water Heater Modeling and Control Strategies for Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Diao, Ruisheng; Lu, Shuai; Elizondo, Marcelo A.; Mayhorn, Ebony T.; Zhang, Yu; Samaan, Nader A.

    2012-07-22

    Abstract— Demand response (DR) has a great potential to provide balancing services at normal operating conditions and emergency support when a power system is subject to disturbances. Effective control strategies can significantly relieve the balancing burden of conventional generators and reduce investment on generation and transmission expansion. This paper is aimed at modeling electric water heaters (EWH) in households and tests their response to control strategies to implement DR. The open-loop response of EWH to a centralized signal is studied by adjusting temperature settings to provide regulation services; and two types of decentralized controllers are tested to provide frequency support following generator trips. EWH models are included in a simulation platform in DIgSILENT to perform electromechanical simulation, which contains 147 households in a distribution feeder. Simulation results show the dependence of EWH response on water heater usage . These results provide insight suggestions on the need of control strategies to achieve better performance for demand response implementation. Index Terms— Centralized control, decentralized control, demand response, electrical water heater, smart grid

  15. Grower demand for sensor-controlled irrigation

    Science.gov (United States)

    Lichtenberg, Erik; Majsztrik, John; Saavoss, Monica

    2015-01-01

    Water scarcity is likely to increase in the coming years, making improvements in irrigation efficiency increasingly important. An emerging technology that promises to increase irrigation efficiency substantially is a wireless irrigation sensor network that uploads sensor data into irrigation management software, creating an integrated system that allows real-time monitoring and control of moisture status that has been shown in experimental settings to reduce irrigation costs, lower plant loss rates, shorten production times, decrease pesticide application, and increase yield, quality, and profit. We use an original survey to investigate likely initial acceptance, ceiling adoption rates, and profitability of this new sensor network technology in the nursery and greenhouse industry. We find that adoption rates for a base system and demand for expansion components are decreasing in price, as expected. The price elasticity of the probability of adoption suggests that sensor networks are likely to diffuse at a rate somewhat greater than that of drip irrigation. Adoption rates for a base system and demand for expansion components are increasing in specialization in ornamental production: growers earning greater shares of revenue from greenhouse and nursery operations are willing to pay more for a base system and are willing to purchase larger numbers of expansion components at any given price. We estimate that growers who are willing to purchase a sensor network expect investment in this technology to generate significant profit, consistent with findings from experimental studies.

  16. Job control, job demands, social support at work and health among adolescent workers Controle, exigências, apoio social no trabalho e efeitos na saúde de trabalhadores adolescentes

    Directory of Open Access Journals (Sweden)

    Frida M Fischer

    2005-04-01

    Full Text Available OBJECTIVE: To evaluate physical and psychological dimensions of adolescent labor (such as job demands, job control, and social support in the work environment, and their relation to reported body pain, work injuries, sleep duration and daily working hours. METHODS: A total of 354 adolescents attending evening classes at a public school in São Paulo, Brazil, answered questionnaires regarding their living and working conditions (Karasek's Job Content Questionnaire, 1998, and their health status. Data collection took place in April and May 2001. Multiple logistic regression analysis was used to determine relations among variables. RESULTS: Psychological job demands were related to body pain (OR=3.3, higher risk of work injuries (OR=3.0 and reduced sleep duration in weekdays (Monday to Thursday (pOBJETIVO: Avaliar as dimensões físicas e psicológicas do trabalho de adolescentes (demanda de trabalho, controle no trabalho e apoio social e ambiental, relacionando-os a relatos de: dores no corpo, acidentes de trabalho, duração de sono e duração diária da jornada de trabalho. MÉTODOS: Participaram do estudo 354 estudantes do período noturno de escola pública no Município de São Paulo, entre abril e maio de 2001. Esses, responderam a questionário sobre condições de vida, trabalho (escalas Karasek de controle no trabalho e estado de saúde. Foram feitas análises de regressão logística múltipla a fim de determinar a relação entre variáveis. RESULTADOS: As exigências psicológicas mostraram-se associadas aos relatos de dores no corpo (OR=3,3, maiores riscos de ocorrência de acidentes de trabalho (OR=3,0 e redução da duração do sono durante os dias de semana (segunda a quinta-feira (p<0,01. Baixa autoridade de decisão (p=0,03 e maior segurança no emprego (p=0,02 estão relacionadas à maior duração da jornada diária de trabalho. CONCLUSÕES: Concluiu-se que não somente os estressores físicos, mas também os psicol

  17. Demand Response on domestic thermostatically controlled loads

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam

    . For a safe and reliable operation of electric power systems, the balance between electricity generation and consumption has to be maintained. The conventional fossil fuel based power generation achieves this balance by adjusting the generation to follow the consumption. In the electric power system......Electricity has become an inevitable part of human life in present day world. In the past two centuries, the electric power system has undergone a lot of changes. Due to the awareness about the adverse impact of the fossil fuels, the power industry is adopting green and sustainable energy sources....... In general, the electricity consumers are classified as industrial, commercial and domestic. In this dissertation, only the thermostatically controlled loads (TCLs) in the domestic segment are considered for the demand response study. The study is funded by Danish Council for Strategic Research (DCSR...

  18. History of demand side management and classification of demand response control schemes

    NARCIS (Netherlands)

    Lampropoulos, I.; Kling, W.L.; Ribeiro, P.F.; Berg, van den J.

    2013-01-01

    The scope of this paper is to provide a review on the topic of demand side management. A historical overview provides a critical insight to applied cases, while the discovery of new evidence calls for reconsideration of the design of demand response control schemes. The developments at the demand

  19. Lighting Systems Control for Demand Response

    NARCIS (Netherlands)

    Husen, S.A.; Pandharipande, A.; Tolhuizen, L.M.G.; Wang, Y.; Zhao, M.

    2012-01-01

    Lighting is a major part of energy consumption in buildings. Lighting systems will thus be one of the important component systems of a smart grid for dynamic load management services like demand response.In the scenario considered in this paper, under a demand response request, lighting systems in a

  20. Cognitive task demands, self-control demands and the mental well-being of office workers.

    Science.gov (United States)

    Bridger, Robert S; Brasher, Kate

    2011-09-01

    The cognitive task demands of office workers and the self-control demands of their work roles were measured in a sample of 196 employees in two different office layouts using a self-report questionnaire, which was circulated electronically. Multiple linear regression analysis revealed that both factors were associated with mental well-being, but not with physical well-being, while controlling for exposure to psychosocial stressors. The interaction between cognitive task demands and self-control demands had the strongest association with mental well-being, suggesting that the deleterious effect of one was greater when the other was present. An exploratory analysis revealed that the association was stronger for employees working in a large open-plan office than for those working in smaller offices with more privacy. Frustration of work goals was the cognitive task demand having the strongest negative impact on mental well-being. Methodological limitations and scale psychometrics (particularly the use of the NASA Task Load Index) are discussed. STATEMENT OF RELEVANCE: Modern office work has high mental demands and low physical demands and there is a need to design offices to prevent adverse psychological reactions. It is shown that cognitive task demands interact with self-control demands to degrade mental well-being. The association was stronger in an open-plan office.

  1. Decision support program for congestion management using demand side flexibility

    DEFF Research Database (Denmark)

    Esmat, Ayman; Pinson, Pierre; Usaola, Julio

    2017-01-01

    In the past decades, Distribution System Operators (DSOs) have been mitigating distribution networks (DNs) contingencies by opting to grid reinforcements. However, this approach is not always cost and time efficient. Demand Side Flexibility (DSF) is one of the recent alternatives used in DNs cong...... effect is taken into consideration as well as the uncertain behavior of customers. Finally, the distribution grid of the Danish Bornholm Island is used to illustrate the merits of the DSP. The total cost incurred by the DSO is calculated and presented.......In the past decades, Distribution System Operators (DSOs) have been mitigating distribution networks (DNs) contingencies by opting to grid reinforcements. However, this approach is not always cost and time efficient. Demand Side Flexibility (DSF) is one of the recent alternatives used in DNs...... congestion management. Consequently, new market players such as aggregators are needed to handle DSF transaction between customers and DSOs. This paper proposes and models a decision support program (DSP) to optimize the total cost charged by the DSO for using DSF services. Moreover, the energy rebound...

  2. An Intuitive Definition of Demand Flexibility in Direct Load Control

    DEFF Research Database (Denmark)

    Tahersima, Fatemeh; Madsen, Per Printz; Andersen, Palle

    2013-01-01

    Two control approaches: direct and indirect control of demand side energy management in a smart grid are studied. Indirect control of energy demands is based on economic incentives. In this approach, consumers will shift their energy consumption with the benefit of a cut down in the electricity b...

  3. Applying demand side management using a generalised grid supportive approach

    NARCIS (Netherlands)

    Blaauwbroek, N.; Nguyen, H.P.; Slootweg, J.G.

    2017-01-01

    Demand side management is often seen as a promising tool for distribution network operators to mitigate network operation limit violations. Many demand side management applications have been proposed, each with their own objectives and methodology. Quite often, these demand side management

  4. Job Stress Across Gender: The Importance of Emotional and Intellectual Demands and Social Support in Women

    Directory of Open Access Journals (Sweden)

    María José Montero-Simó

    2013-01-01

    Full Text Available This study aims to analyse whether any differences exist between the genders with respect to the effect of perceived Job Demands, Control and Support (JDCS model on how individuals reach high levels of job stress. To do this, the perceived risk of suffering an illness or having an accident in the workplace is used as an outcome measure. The study is based on the First Survey on Working Conditions in Andalusia, which has a sample of 5,496 men and 2,779 women. We carry out a multi-sample analysis with structural equation models, controlling for age and sector. The results show that the generation of job stress has a different pattern in men and women. In the case of men, the results show that only one dimension of the job demands stressor is significant (quantitative demands, whose effect on job stress is weakened slightly by the direct effects of control and support. With women, in contrast, emotional and intellectual aspects (qualitative demands are also statistically significant. Moreover, social support has a greater weakening effect on the levels of job stress in women than in men. These results suggest that applying the JDCS model in function of the gender will contribute to a greater understanding of how to reduce the levels of job stress in men and women, helping the design of more effective policies in this area.

  5. Demand for and availability of online support to stop smoking

    Directory of Open Access Journals (Sweden)

    Beatriz Helena Carlini

    2012-12-01

    Full Text Available OBJECTIVES: Estimate the frequency of online searches on the topic of smoking and analyze the quality of online resources available to smokers interested in giving up smoking. METHODS: Search engines were used to revise searches and online resources related to stopping smoking in Brazil in 2010. The number of searches was determined using analytical tools available on Google Ads; the number and type of sites were determined by replicating the search patterns of internet users. The sites were classified according to content (advertising, library of articles and other. The quality of the sites was analyzed using the Smoking Treatment Scale- Content (STS-C and the Smoking Treatment Scale - Rating (STS-R. RESULTS: A total of 642,446 searches was carried out. Around a third of the 113 sites encountered were of the 'library' type, i.e. they only contained articles, followed by sites containing clinical advertising (18.6 and professional education (10.6. Thirteen of the sites offered advice on quitting directed at smokers. The majority of the sites did not contain evidence-based information, were not interactive and did not have the possibility of communicating with users after the first contact. Other limitations we came across were a lack of financial disclosure as well as no guarantee of privacy concerning information obtained and no distinction made between editorial content and advertisements. CONCLUSIONS: There is a disparity between the high demand for online support in giving up smoking and the scarcity of quality online resources for smokers. It is necessary to develop interactive, customized online resources based on evidence and random clinical testing in order to improve the support available to Brazilian smokers.

  6. Psychological demand and control of the work process of public university servants.

    Science.gov (United States)

    Moura, Denise Cristina Alves de; Greco, Rosangela Maria; Paschoalin, Heloisa Campos; Portela, Luciana Fernandes; Arreguy-Sena, Cristina; Chaoubah, Alfredo

    2018-02-01

    This cross-sectional research aimed to analyze the psychological demand and work control self-reported by the Education Administrative Technicians of a public university. This is a complete sample selection consisting of 833 Education Administrative Technicians who self-completed a questionnaire with questions structured in 2013/2014. A descriptive bivariate analysis was performed with the calculation of psychosocial stress at work, using the Demand-Control Model quadrants categorized as: low-demand work (low-demand and high-control), reference group, passive work (low-demand and low-control), active work (high-demand and high-control), high-demand (high-demand and low-control) - group with the highest exposure. The study complies with all ethical and legal research requirements involving human beings. There was a predominance of the category of workers performing passive work (n = 319, 39.7%), low work demand (n = 274, 34.1%), high work demand (n = 116, 14.4%) and active work (n = 95, 11.8%). There were contributions from the investigation on the health of these workers insofar as they provided a diagnosis of the category. There is a recommendation for such data to support interventions to empower them and retailor jobs.

  7. Fast demand response in support of the active distribution network

    NARCIS (Netherlands)

    MacDougall, P.; Heskes, P.; Crolla, P.; Burt, G.; Warmer, C.

    2013-01-01

    Demand side management has traditionally been investigated for "normal" operation services such as balancing and congestion management. However they potentially could be utilized for Distributed Network Operator (DNO) services. This paper investigates and validates the use of a supply and demand

  8. Modelling Per Capita Water Demand Change to Support System Planning

    Science.gov (United States)

    Garcia, M. E.; Islam, S.

    2016-12-01

    Water utilities have a number of levers to influence customer water usage. These include levers to proactively slow demand growth over time such as building and landscape codes as well as levers to decrease demands quickly in response to water stress including price increases, education campaigns, water restrictions, and incentive programs. Even actions aimed at short term reductions can result in long term water usage declines when substantial changes are made in water efficiency, as in incentives for fixture replacement or turf removal, or usage patterns such as permanent lawn watering restrictions. Demand change is therefore linked to hydrological conditions and to the effects of past management decisions - both typically included in water supply planning models. Yet, demand is typically incorporated exogenously using scenarios or endogenously using only price, though utilities also use rules and incentives issued in response to water stress and codes specifying standards for new construction to influence water usage. Explicitly including these policy levers in planning models enables concurrent testing of infrastructure and policy strategies and illuminates interactions between the two. The City of Las Vegas is used as a case study to develop and demonstrate this modeling approach. First, a statistical analysis of system data was employed to rule out alternate hypotheses of per capita demand decrease such as changes in population density and economic structure. Next, four demand sub-models were developed including one baseline model in which demand is a function of only price. The sub-models were then calibrated and tested using monthly data from 1997 to 2012. Finally, the best performing sub-model was integrated with a full supply and demand model. The results highlight the importance of both modeling water demand dynamics endogenously and taking a broader view of the variables influencing demand change.

  9. GLUT4 Mobilization Supports Energetic Demands of Active Synapses.

    Science.gov (United States)

    Ashrafi, Ghazaleh; Wu, Zhuhao; Farrell, Ryan J; Ryan, Timothy A

    2017-02-08

    The brain is highly sensitive to proper fuel availability as evidenced by the rapid decline in neuronal function during ischemic attacks and acute severe hypoglycemia. We previously showed that sustained presynaptic function requires activity-driven glycolysis. Here, we provide strong evidence that during action potential (AP) firing, nerve terminals rely on the glucose transporter GLUT4 as a glycolytic regulatory system to meet the activity-driven increase in energy demands. Activity at synapses triggers insertion of GLUT4 into the axonal plasma membrane driven by activation of the metabolic sensor AMP kinase. Furthermore, we show that genetic ablation of GLUT4 leads to an arrest of synaptic vesicle recycling during sustained AP firing, similar to what is observed during acute glucose deprivation. The reliance on this biochemical regulatory system for "exercising" synapses is reminiscent of that occurring in exercising muscle to sustain cellular function and identifies nerve terminals as critical sites of proper metabolic control. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Do job demands and job control affect problem-solving?

    Science.gov (United States)

    Bergman, Peter N; Ahlberg, Gunnel; Johansson, Gun; Stoetzer, Ulrich; Aborg, Carl; Hallsten, Lennart; Lundberg, Ingvar

    2012-01-01

    The Job Demand Control model presents combinations of working conditions that may facilitate learning, the active learning hypothesis, or have detrimental effects on health, the strain hypothesis. To test the active learning hypothesis, this study analysed the effects of job demands and job control on general problem-solving strategies. A population-based sample of 4,636 individuals (55% women, 45% men) with the same job characteristics measured at two times with a three year time lag was used. Main effects of demands, skill discretion, task authority and control, and the combined effects of demands and control were analysed in logistic regressions, on four outcomes representing general problem-solving strategies. Those reporting high on skill discretion, task authority and control, as well as those reporting high demand/high control and low demand/high control job characteristics were more likely to state using problem solving strategies. Results suggest that working conditions including high levels of control may affect how individuals cope with problems and that workplace characteristics may affect behaviour in the non-work domain.

  11. Demand controlled ventilation for multi-family dwellings

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig

    for centrally balanced DCV systems with heat recovery. A design expected to fulfill this requirement was investigated in detail with regard to its electricity consumption by evaluating a control strategy that resets the static pressure set point at part load. The results showed that this control strategy can......The present thesis “Demand controlled ventilation for multi-family dwellings” constitutes the summary of a three year project period during which demand specification and system design of demand controlled ventilation for residential buildings were studied. Most standards and buildings codes...... can be reduced compared to a system with constant air flow. A literature study on indoor pollutants in homes, their sources and their impact on humans formed the basis for the demand specification. Emission of pollutants in residential buildings roughly fall into constantly emitted background sources...

  12. Performance Assessment of Aggregation Control Services for Demand Response

    DEFF Research Database (Denmark)

    Bondy, Daniel Esteban Morales; Costanzo, Giuseppe Tommaso; Heussen, Kai

    2014-01-01

    Aggregation algorithms that provide services to the grid via demand side management are moving from research ideas to the market. With the diversity of the technology delivering such services, it becomes essential to establish transparent performance standards from a service delivery perspective...... of the quality of service provided by an aggregation control algorithm. By a detailed case study we present and an application of the index, comparing the performance of two different control architectures for demand side management delivering a distribution grid service....

  13. Energy efficient demand controlled ventilation in single family houses

    DEFF Research Database (Denmark)

    Nielsen, Toke Rammer; Drivsholm, Christian

    2010-01-01

    This paper presents a strategy for a simple demand controlled ventilation system for single family houses where all sensors and controls are located in the air handling unit. The strategy is based on sensing CO2-concentration and moisture content in the outdoor air and exhaust air. The CO2...

  14. Indirect Control for Demand Side Management – A Conceptual Introduction

    DEFF Research Database (Denmark)

    Heussen, Kai; You, Shi; Biegel, Benjamin

    2012-01-01

    The concept of “indirect control” has become a relevant discussion term in relation to activation distributed and small-scale demand and generation units to provide resources for power system balancing. The term and its association with price signals has, however caused some confusion as to its...... correct definition, either as a control or a market concept. This paper aims to provide a conceptual introduction to "indirect control" for management of small and distributed demand side resources. A review of control concepts and an analysis of "indirectness" features are provided to create a framework...... for systematic classification of indirect control strategies. The concepts developed then enable a discussion of control performance and valuation of direct- and indirect control strategies....

  15. Demand Management Based on Model Predictive Control Techniques

    Directory of Open Access Journals (Sweden)

    Yasser A. Davizón

    2014-01-01

    Full Text Available Demand management (DM is the process that helps companies to sell the right product to the right customer, at the right time, and for the right price. Therefore the challenge for any company is to determine how much to sell, at what price, and to which market segment while maximizing its profits. DM also helps managers efficiently allocate undifferentiated units of capacity to the available demand with the goal of maximizing revenue. This paper introduces control system approach to demand management with dynamic pricing (DP using the model predictive control (MPC technique. In addition, we present a proper dynamical system analogy based on active suspension and a stability analysis is provided via the Lyapunov direct method.

  16. How Tobacco Control Measures and Smuggling Influence Demand ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    How Tobacco Control Measures and Smuggling Influence Demand in Panama. Panama's tobacco epidemic demonstrates ... Their goal: establish a new threshold for increasing the luxury tax on tobacco products, including cigarettes, based on the monthly evolution of cigarette sales. The researchers will survey brands in ...

  17. Winning end users active support to demand side response

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, Jose [Rede Electrica Nacional, S.A., Lisbon (Portugal); Estanqueiro, Ana [Laboratorio Nacional de Energia e Geologia (LNEG), Lisbon (Portugal)

    2012-07-01

    While objectives proposed for Smart Grids and Smart metering may seem to be able to win easily end user's supports, a considerable amount of studies on social behavior concerning energy efficiency and sustainability show the gap between the values people would like to fulfill and their real life performance. As TSOs envision here a source of System Ancillary Services, measures to make the source really dependable, so that an adequate market design may really work are pointed out. (orig.)

  18. Perceived information and communication technology (ICT) demands on employee outcomes: the moderating effect of organizational ICT support.

    Science.gov (United States)

    Day, Arla; Paquet, Stephanie; Scott, Natasha; Hambley, Laura

    2012-10-01

    Although many employees are using more information communication technology (ICT) as part of their jobs, few studies have examined the impact of ICT on their well-being, and there is a lack of validated measures designed to assess the ICT factors that may impact employee well-being. Therefore, we developed and validated a measure of ICT demands and supports. Using Exploratory Structural Equation Modeling, we found support for 8 ICT demands (i.e., availability, communication, ICT control, ICT hassles, employee monitoring, learning, response expectations, and workload) and two facets of ICT support (personal assistance and resources/upgrades support). Jointly, the ICT demands were associated with increased strain, stress, and burnout and were still associated with stress and strain after controlling for demographics, job variables, and job demands. The two types of ICT support were associated with lower stress, strain, and burnout. Resources/upgrades support moderated the relationship between learning expectations and most strain outcomes and between ICT hassles and strain. Personal assistance support moderated the relationship between ICT hassles and strain.

  19. Production control and supplier selection under demand disruptions

    Directory of Open Access Journals (Sweden)

    Xianzhe Chen

    2010-12-01

    Full Text Available This paper investigates the effects of demand disruptions on production control and supplier selection in a three-echelon supply chain system. The customer demand is modeled as a jump-diffusion process in a continuous-time setting. A two-number production-inventory policy is implemented in the production control model for the manufacturer. The objective is to minimize the long-term average total cost consisting of backlog cost, holding cost, switching cost, and ordering cost. The simulated annealing method is applied to search the optimal critical switching values. Furthermore, an improved analytical hierarchy process (AHP is proposed to select the best supplier, based on quantitative factors such as the optimal long-term total cost obtained through the simulated annealing method under demand disruptions and qualitative factors such as quality and service. Numerical studies are conducted to demonstrate the effects of demand disruptions in the face of various risk scenarios. Managerial insights from simulation results are provided as well. Our approaches can be implemented as the “stress test” for companies in front of various supply chain disruption scenarios.

  20. Control strategies for demand controlled ventilation in dwellings

    DEFF Research Database (Denmark)

    Nielsen, Toke Rammer; Drivsholm, Christian

    2011-01-01

    and efficient fans is becoming the standard solution. The building regulation requirement for air change in dwellings is often a constant value that has been chosen to avoid moisture related problems in the indoor environment. This required air change is sometimes sufficient, sometimes too low and sometimes too....... In the studied house two control strategies were tested. A simple strategy where all sensors and controls were located in the air handling unit and only the speed of the fans can be controlled, and a complex strategy where sensors were placed in each room and where individual control of air flow in each room...

  1. Optimization of Occupancy Based Demand Controlled Ventilation in Residences

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Walker, Iain; Sherman, Max

    2011-01-01

    Although it has been used for many years in commercial buildings, the application of demand controlled ventilation in residences is limited. In this study we used occupant exposure to pollutants integrated over time (referred to as "dose") as the metric to evaluate the effectiveness and air quality...... implications of demand controlled ventilation in residences. We looked at air quality for two situations. The first is that typically used in ventilation standards: the exposure over a long term. The second is to look at peak exposures that are associated with time variations in ventilation rates and pollutant...... when occupied. We used analytical solutions to the continuity equation to determine the ventilation effectiveness and the long-term chronic dose and peak acute exposure for a representative range of occupancy periods, pollutant generation rates and airflow rates. The results of the study showed that we...

  2. A demand assignment control in international business satellite communications network

    Science.gov (United States)

    Nohara, Mitsuo; Takeuchi, Yoshio; Takahata, Fumio; Hirata, Yasuo

    An experimental system is being developed for use in an international business satellite (IBS) communications network based on demand-assignment (DA) and TDMA techniques. This paper discusses its system design, in particular from the viewpoints of a network configuration, a DA control, and a satellite channel-assignment algorithm. A satellite channel configuration is also presented along with a tradeoff study on transmission rate, HPA output power, satellite resource efficiency, service quality, and so on.

  3. Transactive Control of Commercial Buildings for Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Hao, He; Corbin, Charles D.; Kalsi, Karanjit; Pratt, Robert G.

    2017-01-01

    Transactive control is a type of distributed control strategy that uses market mechanism to engage self-interested responsive loads to achieve power balance in the electrical power grid. In this paper, we propose a transactive control approach of commercial building Heating, Ventilation, and Air- Conditioning (HVAC) systems for demand response. We first describe the system models, and identify their model parameters using data collected from Systems Engineering Building (SEB) located on our Pacific Northwest National Laboratory (PNNL) campus. We next present a transactive control market structure for commercial building HVAC system, and describe its agent bidding and market clearing strategies. Several case studies are performed in a simulation environment using Building Control Virtual Test Bed (BCVTB) and calibrated SEB EnergyPlus model. We show that the proposed transactive control approach is very effective at peak clipping, load shifting, and strategic conservation for commercial building HVAC systems.

  4. Protecting workers in the home care industry: workers' experienced job demands, resource gaps, and benefits following a socially supportive intervention.

    Science.gov (United States)

    Mabry, Linda; Parker, Kelsey N; Thompson, Sharon V; Bettencourt, Katrina M; Haque, Afsara; Luther Rhoten, Kristy; Wright, Rob R; Hess, Jennifer A; Olson, Ryan

    2018-05-02

    The Community of Practice and Safety Support (COMPASS) program is a peer-led group intervention for home care workers. In a randomized controlled trial, COMPASS significantly improved workers' professional support networks and safety and health behaviors. However, quantitative findings failed to capture workers' complex emotional, physical, and social experiences with job demands, resource limitations, and the intervention itself. Therefore, we conducted qualitative follow-up interviews with a sample of participants (n = 28) in the program. Results provided examples of unique physical and psychological demands, revealed stressful resource limitations (e.g., safety equipment access), and elucidated COMPASS's role as a valuable resource.

  5. Accumulative job demands and support for strength use: Fine-tuning the job demands-resources model using conservation of resources theory.

    Science.gov (United States)

    van Woerkom, Marianne; Bakker, Arnold B; Nishii, Lisa H

    2016-01-01

    Absenteeism associated with accumulated job demands is a ubiquitous problem. We build on prior research on the benefits of counteracting job demands with resources by focusing on a still untapped resource for buffering job demands-that of strengths use. We test the idea that employees who are actively encouraged to utilize their personal strengths on the job are better positioned to cope with job demands. Based on conservation of resources (COR) theory, we hypothesized that job demands can accumulate and together have an exacerbating effect on company registered absenteeism. In addition, using job demands-resources theory, we hypothesized that perceived organizational support for strengths use can buffer the impact of separate and combined job demands (workload and emotional demands) on absenteeism. Our sample consisted of 832 employees from 96 departments (response rate = 40.3%) of a Dutch mental health care organization. Results of multilevel analyses indicated that high levels of workload strengthen the positive relationship between emotional demands and absenteeism and that support for strength use interacted with workload and emotional job demands in the predicted way. Moreover, workload, emotional job demands, and strengths use interacted to predict absenteeism. Strengths use support reduced the level of absenteeism of employees who experienced both high workload and high emotional demands. We conclude that providing strengths use support to employees offers organizations a tool to reduce absenteeism, even when it is difficult to redesign job demands. (c) 2016 APA, all rights reserved).

  6. Relative effects of demand and control on task-related cardiovascular reactivity, task perceptions, performance accuracy, and mood.

    Science.gov (United States)

    Flynn, Niamh; James, Jack E

    2009-05-01

    The hypothesis that work control has beneficial effects on well-being is the basis of the widely applied, yet inconsistently supported, Job Demand Control (JDC) Model [Karasek, R.A., 1979. Job demands, job decision latitude and mental strain: Implications for job redesign. Adm. Sci. Q. 24, 285-308.; Karasek, R., Theorell, T., 1990. Healthy Work: Stress, Productivity, and the Reconstruction of Working Life. Basic Books, Oxford]. The model was tested in an experiment (N=60) using a cognitive stressor paradigm that sought to prevent confounding between demand and control. High-demand was found to be associated with deleterious effects on physiological, subjective, and performance outcomes. In contrast, few main effects were found for control. Evidence for the buffer interpretation of the JDC Model was limited to a significant demand-control interaction for performance accuracy, whereas substantial support was found for the strain interpretation of the model [van der Doef, M., Maes, S., 1998. The job demand-control(-support) model and physical health outcomes: A review of the strain and buffer hypotheses. Psychol. Health 13, 909-936., van der Doef, M., Maes, S., 1999. The Job Demand-Control(-Support) model and psychological well-being: A review of 20 years of empirical research. Work Stress 13, 87-114]. Manipulation checks revealed that objective control altered perceptions of control but not perceptions of demand. It is suggested that beneficial effects of work-related control are unlikely to occur in the absence of reductions in perceived demand. Thus, contrary to the propositions of Karasek and colleagues, demand and control do not appear to be independent factors.

  7. ) Band with on Demand Technology Platform to Support Broadband Data Applications

    International Nuclear Information System (INIS)

    Cox, J.

    2003-01-01

    Oil and Gas Companies and their service providers are demanding significantly more bandwidth between their offshore rig locations and their project offices to support real time data applications and video conferencing. SLB Data Marine Systems developed proprietry satellite technology in the North Sea, to allow satellite bandwidth to be 'shared' amongst a population of offshore platforms or vessels and for individual sites to 'pull down' this bandwidth on a demand basis.As well as meeting the new demands of the oil industry with regard to cost effectively transporting these new 'rig to office' applications, this same bandwidth can be used to support telemedicine or distant learning

  8. Worktime demands and work-family interference: Does worktime control buffer the adverse effects of high demands?

    NARCIS (Netherlands)

    Geurts, S.A.E.; Beckers, D.G.J.; Taris, T.W.; Kompier, M.A.J.; Smulders, P.G.W.

    2009-01-01

    This study examined whether worktime control buffered the impact of worktime demands on work-family interference (WFI), using data from 2,377 workers from various sectors of industry in The Netherlands. We distinguished among three types of worktime demands: time spent on work according to one's

  9. Demand Controlled Ventilation in a Combined Ventilation and Radiator System

    OpenAIRE

    Hesaraki, Arefeh; Holmberg, Sture

    2013-01-01

    With growing concerns for efficient and sustainable energy treatment in buildings there is a need for balanced and intelligent ventilation solutions. This paper presents a strategy for demand controlled ventilation with ventilation radiators, a combined heating and ventilation system. The ventilation rate was decreased from normal requirements (per floor area) of 0.375 l·s-1·m-2 to 0.100 l·s-1·m-2 when the residence building was un-occupied. The energy saving potential due to decreased ventil...

  10. Product demand forecasts using wavelet kernel support vector machine and particle swarm optimization in manufacture system

    Science.gov (United States)

    Wu, Qi

    2010-03-01

    Demand forecasts play a crucial role in supply chain management. The future demand for a certain product is the basis for the respective replenishment systems. Aiming at demand series with small samples, seasonal character, nonlinearity, randomicity and fuzziness, the existing support vector kernel does not approach the random curve of the sales time series in the space (quadratic continuous integral space). In this paper, we present a hybrid intelligent system combining the wavelet kernel support vector machine and particle swarm optimization for demand forecasting. The results of application in car sale series forecasting show that the forecasting approach based on the hybrid PSOWv-SVM model is effective and feasible, the comparison between the method proposed in this paper and other ones is also given, which proves that this method is, for the discussed example, better than hybrid PSOv-SVM and other traditional methods.

  11. Technology Transfer Opportunities: On-Demand Printing in Support of National Geospatial Data

    Science.gov (United States)

    ,

    1997-01-01

    The U.S. Geological Survey (USGS) and the 3M Company of St. Paul, Minnesota, have entered into a cooperative research and development agreement (CRADA) to investigate maps-on-demand technology to support the production of USGS mapping products. The CRADA will potentially help the USGS to develop on-demand alternatives to lithographic maps and help 3M to develop a series of commercial instant map-printing systems.

  12. Architectural Considerations for Highly Scalable Computing to Support On-demand Video Analytics

    Science.gov (United States)

    2017-04-19

    research were used to implement a distributed on-demand video analytics system that was prototyped for the use of forensics investigators in law...demand video intelligence; intelligent video system ; video analytics platform I. INTRODUCTION Video Analytics systems has been of tremendous interest...enforcement. The system was tested in the wild using video files as well as a commercial Video Management System supporting more than 100 surveillance

  13. Integrated Control System Engineering Support.

    Science.gov (United States)

    1984-12-01

    Advanced Medium Range Air to Air Missile ASTEC Advanced Speech Technology Experimental Configuration BA Body Axis BCIU Bus Control Interface Unit BMU Bus...support nreeded to tie an ASTEC speech recognition system into the DIGISYN fJcility and support an FIGR experiment designed to investigate the voice...information passed to the PDP computer consisted of integers which represented words or phrases recognized by the ASTEC recognition system. An interface

  14. The moderating role of decision authority and coworker- and supervisor support on the impact of job demands in nursing homes: A cross-sectional study

    NARCIS (Netherlands)

    Willemse, B.M.; de Jonge, J.; Smit, D.; Depla, M.F.I.A.; Pot, A.M.

    2012-01-01

    Background: Healthcare workers in nursing homes are faced with high job demands that can have a detrimental impact on job-related outcomes, such as job satisfaction. Job resources may have a buffering role on this relationship. The Demand-Control-Support (DCS) Model offers a theoretical framework to

  15. Distributed control system for demand response by servers

    Science.gov (United States)

    Hall, Joseph Edward

    Within the broad topical designation of smart grid, research in demand response, or demand-side management, focuses on investigating possibilities for electrically powered devices to adapt their power consumption patterns to better match generation and more efficiently integrate intermittent renewable energy sources, especially wind. Devices such as battery chargers, heating and cooling systems, and computers can be controlled to change the time, duration, and magnitude of their power consumption while still meeting workload constraints such as deadlines and rate of throughput. This thesis presents a system by which a computer server, or multiple servers in a data center, can estimate the power imbalance on the electrical grid and use that information to dynamically change the power consumption as a service to the grid. Implementation on a testbed demonstrates the system with a hypothetical but realistic usage case scenario of an online video streaming service in which there are workloads with deadlines (high-priority) and workloads without deadlines (low-priority). The testbed is implemented with real servers, estimates the power imbalance from the grid frequency with real-time measurements of the live outlet, and uses a distributed, real-time algorithm to dynamically adjust the power consumption of the servers based on the frequency estimate and the throughput of video transcoder workloads. Analysis of the system explains and justifies multiple design choices, compares the significance of the system in relation to similar publications in the literature, and explores the potential impact of the system.

  16. Optimised control and pipe burst detection by water demand forecasting

    NARCIS (Netherlands)

    Bakker, M.

    2014-01-01

    Water demand forecasting The total water demand in an area is the sum of the water demands of all individual domestic and industrial consumers in that area. These consumers behave in repetitive daily, weekly and annual patterns, and the same repetitive patterns can be observed in the drinking water

  17. Hierarchical Control Architecture for Demand Response in Smart Grid Scenario

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    , a number of issues, including DR enabling technologies, control strategy, and control architecture, are still under discussion. This paper outlines novel control requirements based on the categorization of existing DR techniques. More specifically, the roles and responsibilities of smart grid actors...... effective tool for optimum asset utilization and to avoid or delay the need for new infrastructure investment. Furthermore, most of the power networks are under the process of reconfiguration to realize the concept of smart grid and are at the transforming stage to support various forms of DR. However...... for every DR category are allotted and their mode of interactions to coordinate individual as well as coordinative goals is described. Next, hierarchical control architecture (HCA) is developed for the overall coordination of control strategies for individual DR categories. The involved issues are discussed...

  18. Demand driven decision support for efficient water resources allocation in irrigated agriculture

    Science.gov (United States)

    Schuetze, Niels; Grießbach, Ulrike Ulrike; Röhm, Patric; Stange, Peter; Wagner, Michael; Seidel, Sabine; Werisch, Stefan; Barfus, Klemens

    2014-05-01

    Due to climate change, extreme weather conditions, such as longer dry spells in the summer months, may have an increasing impact on the agriculture in Saxony (Eastern Germany). For this reason, and, additionally, declining amounts of rainfall during the growing season the use of irrigation will be more important in future in Eastern Germany. To cope with this higher demand of water, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from the optimized agronomic response at farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF) which provide the estimated yield subject to the minimum amount of irrigation water. These functions take into account the different soil types, crops and stochastically generated climate scenarios. By applying mathematical interpolation and optimization techniques, the SCWPF's are used to compute the water demand considering different constraints, for instance variable and fix costs or the producer price. This generic approach enables the computation for both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance Irrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies for an effective and efficient utilization of water in order to meet future demands. The prototype is implemented as a web-based decision support system and it is based on a service-oriented geo-database architecture.

  19. A Software Environment for an Adaptive Human-Aware Software Agent Supporting Attention-Demanding Tasks

    NARCIS (Netherlands)

    Bosse, T.; Memon, Z.A.; Oorburg, R.; Umair, M.; Treur, J.; de Vos, M.

    2011-01-01

    This paper presents a software environment providing human-aware ambient support for a human performing a task that demands substantial amounts of attention. The agent obtains human attention-awareness in an adaptive manner by use of a dynamical model of human attention, gaze sensoring by an

  20. Demand, Support, and Perception in Family-Related Stress among Protestant Clergy.

    Science.gov (United States)

    Lee, Cameron; Iverson-Gilbert, Judith

    2003-01-01

    Studies of clergy have emphasized the effects of stressors inherent to the profession and the impact of these on the minister's personal and family life. A model of family stress was employed to extend the focus to include three classes of variables: demands, social support, and perception. Results indicated that perception variables are more…

  1. CO2 MONITORING FOR DEMAND CONTROLLED VENTILATION IN COMMERCIAL BUILDINGS

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J.; Sullivan, Douglas P.; Faulkner, David; Eliseeva, Ekaterina

    2010-03-17

    Carbon dioxide (CO{sub 2}) sensors are often deployed in commercial buildings to obtain CO{sub 2} data that are used, in a process called demand-controlled ventilation, to automatically modulate rates of outdoor air ventilation. The objective is to keep ventilation rates at or above design specifications and code requirements and also to save energy by avoiding excessive ventilation rates. Demand controlled ventilation is most often used in spaces with highly variable and sometime dense occupancy. Reasonably accurate CO{sub 2} measurements are needed for successful demand controlled ventilation; however, prior research has suggested substantial measurement errors. Accordingly, this study evaluated: (a) the accuracy of 208 CO{sub 2} single-location sensors located in 34 commercial buildings, (b) the accuracy of four multi-location CO{sub 2} measurement systems that utilize tubing, valves, and pumps to measure at multiple locations with single CO{sub 2} sensors, and (c) the spatial variability of CO{sub 2} concentrations within meeting rooms. The field studies of the accuracy of single-location CO{sub 2} sensors included multi-concentration calibration checks of 90 sensors in which sensor accuracy was checked at multiple CO{sub 2} concentrations using primary standard calibration gases. From these evaluations, average errors were small, -26 ppm and -9 ppm at 760 and 1010 ppm, respectively; however, the averages of the absolute values of error were 118 ppm (16%) and 138 ppm (14%), at concentrations of 760 and 1010 ppm, respectively. The calibration data are generally well fit by a straight line as indicated by high values of R{sup 2}. The Title 24 standard specifies that sensor error must be certified as no greater than 75 ppm for a period of five years after sensor installation. At 1010 ppm, 40% of sensors had errors greater than {+-}75 ppm and 31% of sensors has errors greater than {+-}100 ppm. At 760 ppm, 47% of sensors had errors greater than {+-}75 ppm and 37% of

  2. A predictive control scheme for automated demand response mechanisms

    NARCIS (Netherlands)

    Lampropoulos, I.; Bosch, van den P.P.J.; Kling, W.L.

    2012-01-01

    The development of demand response mechanisms can provide a considerable option for the integration of renewable energy sources and the establishment of efficient generation and delivery of electrical power. The full potential of demand response can be significant, but its exploration still remains

  3. Measuring and controlling unfairness in decentralized planning of energy demand

    NARCIS (Netherlands)

    Pournaras, E.; Vasirani, M.; Kooij, R.E.; Aberer, K.

    2014-01-01

    Demand-side energy management improves robustness and efficiency in Smart Grids. Load-adjustment and load-shifting are performed to match demand to available supply. These operations come at a discomfort cost for consumers as their lifestyle is influenced when they adjust or shift in time their

  4. Islanding Control Architecture in future smart grid with both demand and wind turbine control

    DEFF Research Database (Denmark)

    Chen, Yu; Xu, Zhao; Østergaard, Jacob

    2013-01-01

    , which is the focus of this paper, available resources including both DG units and demand should be fully utilized as reserves. The control and coordination among different resources requires an integral architecture to serve the purpose. This paper develops the Islanding Control Architecture (ICA...

  5. Reward-driven modulation of adaptive control: How prospective monetary gains interact with unpredictable control demands

    NARCIS (Netherlands)

    Marien, Hans; Aarts, Henk; Custers, Ruud

    2014-01-01

    Shifting attention is an effortful control process and incurs a cost on the cognitive system. Previous research suggests that rewards, such as monetary gains, will selectively enhance the ability to shift attention when this demand for control is explicitly cued. Here, we hypothesized that

  6. Modeling, Analysis, and Control of Demand Response Resources

    Energy Technology Data Exchange (ETDEWEB)

    Mathieu, Johanna L. [Univ. of California, Berkeley, CA (United States)

    2012-05-01

    While the traditional goal of an electric power system has been to control supply to fulfill demand, the demand-side can plan an active role in power systems via Demand Response (DR), defined by the Department of Energy (DOE) as “a tariff or program established to motivate changes in electric use by end-use customers in response to changes in the price of electricity over time, or to give incentive payments designed to induce lower electricity use at times of high market prices or when grid reliability is jeopardized” [29]. DR can provide a variety of benefits including reducing peak electric loads when the power system is stressed and fast timescale energy balancing. Therefore, DR can improve grid reliability and reduce wholesale energy prices and their volatility. This dissertation focuses on analyzing both recent and emerging DR paradigms. Recent DR programs have focused on peak load reduction in commercial buildings and industrial facilities (C&I facilities). We present methods for using 15-minute-interval electric load data, commonly available from C&I facilities, to help building managers understand building energy consumption and ‘ask the right questions’ to discover opportunities for DR. Additionally, we present a regression-based model of whole building electric load, i.e., a baseline model, which allows us to quantify DR performance. We use this baseline model to understand the performance of 38 C&I facilities participating in an automated dynamic pricing DR program in California. In this program, facilities are expected to exhibit the same response each DR event. We find that baseline model error makes it difficult to precisely quantify changes in electricity consumption and understand if C&I facilities exhibit event-to-event variability in their response to DR signals. Therefore, we present a method to compute baseline model error and a metric to determine how much observed DR variability results from baseline model error rather than real

  7. An Overview of Demand Side Management Control Schemes for Buildings in Smart Grids

    DEFF Research Database (Denmark)

    Kosek, Anna Magdalena; Costanzo, Giuseppe Tommaso; Bindner, Henrik W.

    2013-01-01

    The increasing share of distributed energy resources and renewable energy in power systems results in a highly variable and less controllable energy production. Therefore, in order to ensure stability and to reduce the infrastructure and operation cost of the power grid, flexible and controllable...... of the power sector in mind and thus can differ significantly in their architecture, their integration into the various markets, their integration into distribution network operation and several other aspects. This paper proposes a classification of load control policies for demand side management in smart...... buildings, based on external behavior: direct, indirect, transactional and autonomous control; internal operation: decision support system scope, control strategy, failure handling and architecture. This classification assists in providing an overview of the control schemes as well as different ways...

  8. Longitudinal Mediation Modeling of Unhealthy Behaviors as Mediators between Workplace Demands/Support and Depressive Symptoms.

    Science.gov (United States)

    Magnusson Hanson, Linda L; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo

    2016-01-01

    Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms.

  9. Longitudinal Mediation Modeling of Unhealthy Behaviors as Mediators between Workplace Demands/Support and Depressive Symptoms

    Science.gov (United States)

    Magnusson Hanson, Linda L.; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo

    2016-01-01

    Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms. PMID:28036376

  10. Technical supports for nuclear control

    Energy Technology Data Exchange (ETDEWEB)

    An, Jong Sung; Kwak, Eun Hoh; Noh, Sung Kee; Soh, Dong Sub; Yoon, Wan Kee; Shin, Jang Soo; Paek, Dae Hyun; Park, Wan Soo; Kim, Hyun Tae; Park, Chan Sik; Cha, Hong Yul; Choi, Yoon Dong; Park, Jin Hoh; Lee, Eui Jin; An, Jin Soo; Kim, Jong Heui [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-12-01

    The project was carried out to support the establishment of the system of accountancy and control of nuclear materials in Korea. The training of inspectors and seminar were held to improve inspection capability of the nuclear inspectors. The information about the north Korean nuclear activities were successfully analyzed. In the drafts of nuclear energy law the national inspection and the regulation of physical protection were newly introduced for the purpose to clarify the openness of nuclear activities in Korea. 1 fig, 20 tabs, 19 refs. (Author).

  11. Environmental control medical support team

    Science.gov (United States)

    Crump, William J.; Kilgore, Melvin V., Jr.

    1988-01-01

    The activities conducted in support of the Environmental Control and Life Support Team during December 7, 1987 through September 30, 1988 are summarized. The majority of the ongoing support has focused on the ECLSS area. Through a series of initial meetings with the ECLSS team and technical literature review, an initial list of critical topics was developed. Subtasks were then identified or additional related tasks received as action items from the ECLSS group meetings. Although most of the efforts focused on providing MSFC personnel with information regarding specific questions and problems related to ECLSS issues, other efforts regarding identifying an ECLSS Medical Support Team and constructing data bases of technical information were also initiated and completed. The specific tasks are as follows: (1) Provide support to the mechanical design and integration of test systems as related to microbiological concerns; (2) Assist with design of Human Subjects Test Protocols; (3) Interpretation and recommendations pertaining to air/water quality requirements; (4) Assist in determining the design specifications required as related to the Technical Demonstration Program; (5) Develop a data base of all microorganisms recovered from previous subsystem testing; (6) Estimates of health risk of individual microbes to test subjects; (7) Assist with setting limits for safety of test subjects; (8) Health monitoring of test subjects; (9) Assist in the preparation of test plans; (10) Assist in the development of a QA/QC program to assure the validity, accuracy and precision of the analyses; and (11) Assist in developing test plans required for future man in the loop testing.

  12. Access control for on-demand provisioned cloud infrastructure services

    NARCIS (Netherlands)

    Ngo, C.T.

    2016-01-01

    The evolution of Cloud Computing brings advantages to both customers and service providers to utilize and manage computing and network resources more efficiently with virtualization, service-oriented architecture technologies, and automated on-demand resource provisioning. However, these advantages

  13. Wind Farm Dispatch Control for Demand Tracking and Minimized Fatigue

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Schiøler, Henrik; Leth, John-Josef

    2012-01-01

    This work presents a strategy for dispatching production references to the individual turbines in a wind farm, such that an overall production demand for the farm is obeyed, while the fatigue experienced by the turbines is minimized. Using a turbine fatigue model for simulating the aging across...... the farm, we show that a 17 % reduction of the turbine aging can be obtained compared to a commonly employed industrial dispatcher, without degrading the power demand tracking....

  14. Flexible brain network reconfiguration supporting inhibitory control.

    Science.gov (United States)

    Spielberg, Jeffrey M; Miller, Gregory A; Heller, Wendy; Banich, Marie T

    2015-08-11

    The ability to inhibit distracting stimuli from interfering with goal-directed behavior is crucial for success in most spheres of life. Despite an abundance of studies examining regional brain activation, knowledge of the brain networks involved in inhibitory control remains quite limited. To address this critical gap, we applied graph theory tools to functional magnetic resonance imaging data collected while a large sample of adults (n = 101) performed a color-word Stroop task. Higher demand for inhibitory control was associated with restructuring of the global network into a configuration that was more optimized for specialized processing (functional segregation), more efficient at communicating the output of such processing across the network (functional integration), and more resilient to potential interruption (resilience). In addition, there were regional changes with right inferior frontal sulcus and right anterior insula occupying more central positions as network hubs, and dorsal anterior cingulate cortex becoming more tightly coupled with its regional subnetwork. Given the crucial role of inhibitory control in goal-directed behavior, present findings identifying functional network organization supporting inhibitory control have the potential to provide additional insights into how inhibitory control may break down in a wide variety of individuals with neurological or psychiatric difficulties.

  15. Scientifically supported mental health intervention in schools: meeting accountability demands with an online resource.

    Science.gov (United States)

    Powers, Joelle D

    2012-01-01

    Legislation has been passed that holds schools increasingly accountable for the proficiency of all students, including those with mental health problems. A critical obstacle impeding the ability of schools to effectively support students is the lack of access to quick, pre-screened, and organized information about scientifically-supported interventions that effectively address youth mental health problems. A new mental health best practices database was developed and made available online that provides access to free and user-friendly information about evidence-based interventions for use in schools. School staff will be better able to meet accountability demands of legislation and to effectively respond to student mental health problems.

  16. Control for large scale demand response of thermostatic loads

    DEFF Research Database (Denmark)

    Totu, Luminita Cristiana; Leth, John; Wisniewski, Rafal

    2013-01-01

    appliances with on/off operation. The objective is to reduce the consumption peak of a group of loads composed of both flexible and inflexible units. The power flexible units are the thermostat-based appliances. We discuss a centralized, model predictive approach and a distributed structure with a randomized......Demand response is an important Smart Grid concept that aims at facilitating the integration of volatile energy resources into the electricity grid. This paper considers a residential demand response scenario and specifically looks into the problem of managing a large number thermostatbased...

  17. Perceived safety climate, job demands, and coworker support among union and nonunion injured construction workers.

    Science.gov (United States)

    Gillen, Marion; Baltz, Davis; Gassel, Margy; Kirsch, Luz; Vaccaro, Diane

    2002-01-01

    This study evaluated injured construction workers' perceptions of workplace safety climate, psychological job demands, decision latitude, and coworker support, and the relationship of these variables to the injury severity sustained by the workers. Injury severity was assessed using the Health Assessment Questionnaire (HAQ), which evaluates functional limitations. Worker perceptions of workplace variables were determined by two instruments: (a) the Safety Climate Measure for Construction Sites and (b) the Job Content Questionnaire (JCQ). The overall model explained 23% of the variance in injury severity, with unique contributions provided by union status, the Safety Climate Score, and Psychological Job Demands. A positive significant correlation was found between injury severity and the Safety Climate Scores (r = .183, P = .003), and between the Safety Climate Scores and union status (r = .225, P safety climate on 5 of the 10 safety climate items. Union workers were more likely than nonunion workers to: (a) perceive their supervisors as caring about their safety; (b) be made aware of dangerous work practices; (c) have received safety instructions when hired; (d) have regular job safety meetings; and (e) perceive that taking risks was not a part of their job. However, with regard to the 49-item JCQ, which includes Coworker Support, the responses between union and nonunion workers were very similar, indicating an overall high degree of job satisfaction. However, workers who experienced their workplace as more safe also perceived the level of management (r = -.55, P demands, need to be identified.

  18. Railing for safety: job demands, job control, and safety citizenship role definition.

    Science.gov (United States)

    Turner, Nick; Chmiel, Nik; Walls, Melanie

    2005-10-01

    This study investigated job demands and job control as predictors of safety citizenship role definition, that is, employees' role orientation toward improving workplace safety. Data from a survey of 334 trackside workers were framed in the context of R. A. Karasek's (1979) job demands-control model. High job demands were negatively related to safety citizenship role definition, whereas high job control was positively related to this construct. Safety citizenship role definition of employees with high job control was buffered from the influence of high job demands, unlike that of employees with low job control, for whom high job demands were related to lower levels of the construct. Employees facing both high job demands and low job control were less likely than other employees to view improving safety as part of their role orientation. Copyright (c) 2005 APA, all rights reserved.

  19. High quantitative job demands and low coworker support as risk factors for neck pain: Results of a prospective cohort study

    NARCIS (Netherlands)

    Ariëns, G.A.M.; Bongers, P.M.; Hoogendoorn, W.E.; Houtman, I.L.D.; Wal, G. van der; Mechelen, W. van

    2001-01-01

    Study Design. A 3-year prospective cohort study among 1334 workers was conducted. Objective. To determine whether the work-related psychosocial factors of quantitative job demands, conflicting job demands, skill discretion, decision authority, supervisor support, coworker support, and job security

  20. A hard day's night: a longitudinal study on the relationships among job demands and job control, sleep quality and fatigue.

    Science.gov (United States)

    de Lange, Annet H; Kompier, Michiel A J; Taris, Toon W; Geurts, Sabine A E; Beckers, Debby G J; Houtman, Irene L D; Bongers, Paulien M

    2009-09-01

    This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand-control history on the development of sleep quality and fatigue. Based on results of a four-wave complete panel study among 1163 Dutch employees, we found significant effects of job demands and job control on sleep quality and fatigue across a 1-year time lag, supporting the strain hypothesis (Demand-Control model; Karasek and Theorell, Basic Books, New York, 1990). No reversed or reciprocal causal patterns were detected. Furthermore, our results revealed that cumulative exposure to a high-strain work environment (characterized by high job demands and low job control) was associated with elevated levels of sleep-related complaints. Cumulative exposure to a low-strain work environment (i.e. low job demands and high job control) was associated with the highest sleep quality and lowest level of fatigue. Our results revealed further that changes in exposure history were related to changes in reported sleep quality and fatigue across time. As expected, a transition from a non-high-strain towards a high-strain job was associated with a significant increase in sleep-related complaints; conversely, a transition towards a non-high-strain job was not related to an improvement in sleep-related problems.

  1. Volunteers in Circles of Support and Accountability Job Demands, Job Resources, and Outcome.

    Science.gov (United States)

    Höing, Mechtild; Bogaerts, Stefan; Vogelvang, Bas

    2017-09-01

    In Circles of Support and Accountability (CoSA), volunteers support a medium- to high-risk sex offender in his process toward desistance by developing a long-term empathic relationship. More knowledge is needed about the impact of this work on volunteers themselves. In a sample of 40 Dutch CoSA volunteers-at the time constituting 37% of the national population of 108 then active CoSA volunteers-we measured outcome in terms of volunteer satisfaction, determination to continue, compassion satisfaction, burnout and secondary stress, vicarious growth, civic capacities, and professional skills. We explored theoretically derived predictors of positive and negative outcome, and conceptualized them within the Job Demands-Resources model (JD-R). Volunteers reported mainly positive effects, especially high levels of volunteer satisfaction, compassion satisfaction, and determination to continue. Results indicated that job demands and most of the internal job resources were of minor importance. External job resources, especially social support and connectedness, were associated with positive outcome. Connectedness mediated the effect of social support on compassion satisfaction.

  2. Primary Control by ON/OFF Demand-Side Devices

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Hansen, Lars Henrik; Andersen, Palle

    2013-01-01

    We consider an aggregator managing a portfolio of ON/OFF demand-side devices. The devices are able to shift con- sumption in time within certain energy limitations; moreover, the devices are able to measure the system frequency and switch ON and OFF accordingly. We show how the aggregator can...

  3. Gaze control during interceptive actions with different spatiotemporal demands.

    NARCIS (Netherlands)

    Navia, J.A.; Dicks, M.S.; van der Kamp, J; Ruiz, L.

    It is widely accepted that the sources of information used to guide interceptive actions depend on conflicting spatiotemporal task demands. However, there is a paucity of evidence that shows how information pick-up during interceptive actions is adapted to such conflicting constraints. The present

  4. Distributed MPC applied to power demand side control

    NARCIS (Netherlands)

    Larsen, G.K.H.; Pons, J.; Achterop, S.; Scherpen, J.M.A.

    2013-01-01

    In the future, global energy balance of a smart grid system can be achieved by its agents deciding on their own power demand locally and the exchange of these decisions. In this paper, we model a network of households with washing machine programs that can be shifted in time so that the overall

  5. Clustering and Support Vector Regression for Water Demand Forecasting and Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Antonio Candelieri

    2017-03-01

    Full Text Available This paper presents a completely data-driven and machine-learning-based approach, in two stages, to first characterize and then forecast hourly water demand in the short term with applications of two different data sources: urban water demand (SCADA data and individual customer water consumption (AMR data. In the first case, reliable forecasting can be used to optimize operations, particularly the pumping schedule, in order to reduce energy-related costs, while in the second case, the comparison between forecast and actual values may support the online detection of anomalies, such as smart meter faults, fraud or possible cyber-physical attacks. Results are presented for a real case: the water distribution network in Milan.

  6. Demand-Side Contribution to Primary Frequency Control With Wind Farm Auxiliary Control

    DEFF Research Database (Denmark)

    Gomez-Lazaro, Emilio; Munoz-Benavente, Irene; Hansen, Anca Daniela

    2014-01-01

    Maintaining a close balance between power generation and demand is essential for sustaining the quality and reliability of a power system. Currently, due to increased renewable energy generation, frequency deviations and power fluctuations of greater concern are being introduced to the grid...... to the primary frequency control together with an auxiliary frequency control, which is carried out by variable-speed wind turbines through an additional control loop that synthesizes virtual inertia. We have evaluated both the suitability of these two additional control actions counteracting frequency deviation...

  7. The Job Demands-Job Control Model and absence behaviour : results of a 3-year longitudinal study

    NARCIS (Netherlands)

    Smulders, P.G.W.; Nijhuis, F.J.N.

    1999-01-01

    Empirical results of earlier studies only marginally supported the relevance of Karasek's Job Demands-Job Control Model for absence behaviour. Since longitudinal studies with respect to these relations were largely lacking, a four-wave panel study was carried out using data from 1755 male employees

  8. Predictive Control of Demand Side Units Participating in the Primary Frequency Reserve Market

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Stoustrup, Jakob; Andersen, Palle

    2013-01-01

    We consider an aggregator controlling a mixed portfolio of conventional power generators and demand side units. The generators are controllable within certain power and ramp limitations while the demand side units are characterized by flexible consumptions and therefore can be treated as energy...

  9. Stress and counterproductive work behavior: multiple relationships between demands, control, and soldier indiscipline over time.

    Science.gov (United States)

    Tucker, Jennifer S; Sinclair, Robert R; Mohr, Cynthia D; Thomas, Jeffrey L; Salvi, Angela D; Adler, Amy B

    2009-07-01

    Cognitive Resource Theory (CRT) suggests that under high levels of stress, employees are more prone to committing indiscipline. As few studies have examined this relationship over time, the authors conducted a six-wave longitudinal study examining the relationship of soldiers' indiscipline with work demands and control. The study included archival data collected quarterly over 2 years from 1,701 soldiers representing 10 units in garrison (Germany and Italy), in training rotations (Grafenwoehr, Germany), and on peacekeeping deployments (Kosovo, Kuwait). No main effects were found for work overload, and the findings for the moderating effects of control were contradictory. Within each time point, as work overload increased, soldiers who felt less control committed more indiscipline, supporting CRT. Over time, however, as work overload increased, soldiers who perceived less control 6 months earlier committed less indiscipline. Additionally, the authors found reverse causal effects for control such that prior perceptions of a lack of control were associated with indiscipline and prior incidents of indiscipline with less control. (c) 2009 APA, all rights reserved.

  10. Influence of job demands and job control on work-life balance among Taiwanese nurses.

    Science.gov (United States)

    Ng, Lee-Peng; Chen, I-Chi; Ng, Hui-Fuang; Lin, Bo-Yen; Kuar, Lok-Sin

    2017-09-01

    This study investigated the extent to which the job demands and job control of nurses were related to their work-life balance. The inability to achieve work-life balance is one of the major reasons for the declining retention rate among nurses. Job demands and job control are two major work domain factors that can have a significant influence on the work-life balance of nurses. The study measured the job demands, job control and work-life balance of 2040 nurses in eight private hospitals in Taiwan in 2013. Job demands and job control significantly predicted all the dimensions of work-life balance. Job demands increased the level of work-life imbalance among nurses. While job control showed positive effects on work/personal life enhancement, it was found to increase both work interference with personal life and personal life interference with work. Reducing the level of job demands (particularly for psychological demands) between family and career development and maintaining a proper level of job control are essential to the work-life balance of nurses. Flexible work practices and team-based management could be considered by nursing management to lessen job demand pressure and to facilitate job engagement and participation among nurses, thus promoting a better balance between work and personal life. © 2017 John Wiley & Sons Ltd.

  11. Access control infrastructure for on-demand provisioned virtualised infrastructure services

    NARCIS (Netherlands)

    Demchenko, Y.; Ngo, C.; de Laat, C.; Smari, W.W.; Fox, G.C.

    2011-01-01

    Cloud technologies are emerging as a new way of provisioning virtualised computing and infrastructure services on-demand for collaborative projects and groups. Security in provisioning virtual infrastructure services should address two general aspects: supporting secure operation of the provisioning

  12. Neural network controller for Active Demand-Side Management with PV energy in the residential sector

    International Nuclear Information System (INIS)

    Matallanas, E.; Castillo-Cagigal, M.; Gutiérrez, A.; Monasterio-Huelin, F.; Caamaño-Martín, E.; Masa, D.; Jiménez-Leube, J.

    2012-01-01

    Highlights: ► We have developed a neural controller for Active Demand-Side Management. ► The controller consists of Multilayer Perceptrons evolved with a genetic algorithm. ► The architecture of the controller is distributed and modular. ► The simulations show that the electrical local behavior improves. ► Active Demand-Side Management helps users to control his energy behaviour. -- Abstract: In this paper, we describe the development of a control system for Demand-Side Management in the residential sector with Distributed Generation. The electrical system under study incorporates local PV energy generation, an electricity storage system, connection to the grid and a home automation system. The distributed control system is composed of two modules: a scheduler and a coordinator, both implemented with neural networks. The control system enhances the local energy performance, scheduling the tasks demanded by the user and maximizing the use of local generation.

  13. A supervisory approach to microgrid demand response and climate control

    NARCIS (Netherlands)

    Korkas, Christos D.; Baldi, S.; Michailidis, Iakovos; Boutalis, Yiannis; Kosmatopoulos, Elias B.; Antsaklis, Panos J.; Valavanis, Kimon P.; Theiliol, Didier

    2016-01-01

    Microgrids equipped with small-scale renewable-energy generation systems and energy storage units offer challenging opportunity from a control point of view. In fact, in order to improve resilience and enable islanded mode, micro-grid energy management systems must dynamically manage controllable

  14. Life on the line: Job demands, perceived co-worker support for safety, and hazardous work events.

    Science.gov (United States)

    Turner, Nick; Chmiel, Nik; Hershcovis, M Sandy; Walls, Melanie

    2010-10-01

    The present study of 334 United Kingdom trackside workers tested an interaction hypothesis. We hypothesized, drawing on the job demands-resources framework, that perceived support for safety (from senior managers, supervisors, and coworkers) as job resources would weaken the relationship between higher job demands and more frequent hazardous work events. Consistent with social impact theory, we predicted that perceived coworker support for safety would be particularly influential when trackside workers faced higher job demands. Moderated multiple regression showed that, of all three sources of perceived support for safety, perceived coworker support for safety was most important for keeping employees safe in the face of high job demands. © 2010 APA, all rights reserved.

  15. The active learning hypothesis of the job-demand-control model: an experimental examination.

    Science.gov (United States)

    Häusser, Jan Alexander; Schulz-Hardt, Stefan; Mojzisch, Andreas

    2014-01-01

    The active learning hypothesis of the job-demand-control model [Karasek, R. A. 1979. "Job Demands, Job Decision Latitude, and Mental Strain: Implications for Job Redesign." Administration Science Quarterly 24: 285-307] proposes positive effects of high job demands and high job control on performance. We conducted a 2 (demands: high vs. low) × 2 (control: high vs. low) experimental office workplace simulation to examine this hypothesis. Since performance during a work simulation is confounded by the boundaries of the demands and control manipulations (e.g. time limits), we used a post-test, in which participants continued working at their task, but without any manipulation of demands and control. This post-test allowed for examining active learning (transfer) effects in an unconfounded fashion. Our results revealed that high demands had a positive effect on quantitative performance, without affecting task accuracy. In contrast, high control resulted in a speed-accuracy tradeoff, that is participants in the high control conditions worked slower but with greater accuracy than participants in the low control conditions.

  16. Does stimulant use impair housing outcomes in low-demand supportive housing for chronically homeless adults?

    Science.gov (United States)

    Edens, Ellen L; Tsai, Jack; Rosenheck, Robert A

    2014-01-01

    Recent research suggests low-demand housing (i.e., not contingent upon abstinence) is effective in helping people exit homelessness, even among recent active substance users. Whether active users of illicit drugs and stimulants have worse housing outcomes than primary alcohol users, however, is unknown. A total of 149 participants in a multisite supportive housing program who reported high levels of active substance use at program entry were classified as either (1) predominantly "Alcohol Use" (>10 of 30 days alcohol, but not >10 days of drug use) or (2) "Illicit Drug Use" (>10 of 30 days any single illicit drug use with or without alcohol use). Sub-analysis of the "Illicit Drug Use" group compared participants reporting high levels of "Stimulant Use" (>10 days cocaine, crack, or methamphetamine use) to those with high levels of "Non-stimulant Use" (>10 days marijuana or other non-stimulant drug use). Group differences in housing outcomes were examined with mixed model multivariate regression. During 24-month follow-up, days housed increased dramatically for both the "Alcohol Use" and the "Illicit Drug Use" groups without significant differences. Sub-analysis of illicit drug users showed stimulant use was associated with fewer days housed (p = .01) and more days homeless (p = .02) over time. Among illicit drug users, stimulant users have somewhat less successful housing outcomes than other active drug and alcohol users, though both groups maintained substantial housing improvements in low-demand housing. © American Academy of Addiction Psychiatry.

  17. Presenting automatic demand control (ADC) as a new frequency control method in smart grids

    Energy Technology Data Exchange (ETDEWEB)

    Ameli, Mohammad Taghi; Ameli, Ali; Maleki, Hamed [Power and Water Univ. of Technology, Tehran (Iran, Islamic Republic of); Mobarhani, Alireza [Amir Kabir Univ. of Technology, Tehran (Iran, Islamic Republic of)

    2011-07-01

    Electric power is the most important part of human energy consumption, and since it has a low storage coefficient it is of particular importance to establish a balance in demand and generation in order to modify and optimize consumption patterns. The expression ''Smart Grid'' can be used to describe technologies which are applied for the automation and optimization of the generation, transmission and distribution network management. This technology requires the integration of information and communication technology in electrical network operation. This paper will study how the Smart Grid capabilites can be used to manage and optimize power network consumption, as well as how the consumers collaboration process using an AGC (Automatic Generation Control) system acts to provide secondary frequency control through consumed load shedding. Reestablishing the balance between demand and generation in critical network operation is also investigated. In other words, utilizing the above method, a new system, ADC (Automatic Demand Control), is offered for use alongside the AGC system in Smart Grids to restore the frequency value to its nominal value. This can lead to a more competitive electricity market and reduce the system storage while maintaining adequate security and network reliability. One of the benefits of the proposed methods described in this paper, in addition to restoring the frequency value to its nominal value, is lower costs and a more economic network operation through reducing fuel and CO2 emission by managing and controlling the amount of the consumed load in the Smart Grid. Also consumers are given the capability to have a specific timetable to economize on their energy requirements which will also reduce the load peak and the network losses. (orig.)

  18. Reactor control rod supporting structure

    International Nuclear Information System (INIS)

    Akimoto, Tokuzo; Miyata, Hiroshi.

    1984-01-01

    Purpose: To enable stable reactor core control even in extremely great vertical earthquakes, as well as under normal operation conditions in FBR type reactors. Constitution: Since a mechanism for converting the rotational movement of a control rod into vertical movement is placed at the upper portion of the reactor core at high temperature, the mechanism should cause fusion or like other danger after the elapse of a long period of time. In view of the above, the conversion mechanism is disposed to the lower portion of the reactor core at a lower temperature region. Further, the connection between the control rod and the control rod drive can be separated upon great vertical earthquakes. (Seki, T.)

  19. Aggregate modeling of fast-acting demand response and control under real-time pricing

    International Nuclear Information System (INIS)

    Chassin, David P.; Rondeau, Daniel

    2016-01-01

    Highlights: • Demand elasticity for fast-acting demand response load under real-time pricing. • Validated first-principles logistic demand curve matches random utility model. • Logistic demand curve suitable for diversified aggregate loads market-based transactive control systems. - Abstract: This paper develops and assesses the performance of a short-term demand response (DR) model for utility load control with applications to resource planning and control design. Long term response models tend to underestimate short-term demand response when induced by prices. This has two important consequences. First, planning studies tend to undervalue DR and often overlook its benefits in utility demand management program development. Second, when DR is not overlooked, the open-loop DR control gain estimate may be too low. This can result in overuse of load resources, control instability and excessive price volatility. Our objective is therefore to develop a more accurate and better performing short-term demand response model. We construct the model from first principles about the nature of thermostatic load control and show that the resulting formulation corresponds exactly to the Random Utility Model employed in economics to study consumer choice. The model is tested against empirical data collected from field demonstration projects and is shown to perform better than alternative models commonly used to forecast demand in normal operating conditions. The results suggest that (1) existing utility tariffs appear to be inadequate to incentivize demand response, particularly in the presence of high renewables, and (2) existing load control systems run the risk of becoming unstable if utilities close the loop on real-time prices.

  20. Decision support in supervisory control

    International Nuclear Information System (INIS)

    Rasmussen, J.; Goodstein, L.P.

    1985-08-01

    It is argued that the supervisory control of complex industrial processes having a potential for serious consequences in case of accidents requires careful consideration of the allocation of decision making between the three main agents of control; namely the designer, the operator and the automatic control system. In particular, it is advocated that instead of continuing their efforts to make their preplanning of responses and countermeasures more and more complete and restricting the operator's initiative, designers should take advantage of modern information technology to make available to the operators their conceptual models and their processing resources so as to allow the operators to function as their extended arm in coping with the plant. Such an interactive decision making activity would thus benefit from this simultaneous availability of the design basis, up-to-date knowledge of plant status and accumualted operational experience. (author)

  1. Application of Demand-Control Theory to Sign Language Interpreting: Implications for Stress and Interpreter Training.

    Science.gov (United States)

    Dean, Robyn K.; Pollard, Robert Q., Jr.

    2001-01-01

    This article uses the framework of demand-control theory to examine the occupation of sign language interpreting. It discusses the environmental, interpersonal, and intrapersonal demands that impinge on the interpreter's decision latitude and notes the prevalence of cumulative trauma disorders, turnover, and burnout in the interpreting profession.…

  2. Conceptual framework for load controlling : with demand reduction bidding & consumer retention

    NARCIS (Netherlands)

    Babar, M.; Ahamed, I.; Al-Ammar, E.A.

    2013-01-01

    Advancement in demand side management strategies enables smart grid to cope with the increasing energy demand and provide economic benefit to all of its stakeholders. Moreover, emerging concept of smart pricing and advances in load control and communication generate new business opportunities as a

  3. Testing the strain hypothesis of the Demand Control Model to explain severe bullying at work

    NARCIS (Netherlands)

    Notelaers, G.; Baillien, E.; de Witte, H.; Einarsen, S.; Vermunt, J.K.

    2013-01-01

    Workplace bullying has often been attributed to work-related stress, and has been linked to the Job Demand Control Model. The current study aims to further these studies by testing the model for bullying in a heterogeneous sample and by using latent class (LC)-analyses to define different demands

  4. Worktime demands and work-family interference: Does worktime control play a buffering role

    NARCIS (Netherlands)

    Geurts, S.A.E.; Beckers, D.G.J.; Taris, T.W.; Kompier, M.A.J.; Smulders, P.G.W.

    2009-01-01

    This study examined whether worktime control buffered the impact of worktime demands on work–family interference (WFI), using data from 2,377 workers from various sectors of industry in The Netherlands. We distinguished among three types of worktime demands: time spent on work according to one’s

  5. Attention Demand and Postural Control in Children with Hearing Deficit

    Science.gov (United States)

    Derlich, Malgorzata; Krecisz, Krzysztof; Kuczynski, Michal

    2011-01-01

    To elucidate the mechanisms responsible for deteriorated postural control in children with hearing deficit (CwHD), we measured center-of-pressure (COP) variability, mean velocity and entropy in bipedal quiet stance (feet together) with or without the concurrent cognitive task (reaction to visual stimulus) on hard or foam surface in 29 CwHD and a…

  6. The moderating role of decision authority and coworker- and supervisor support on the impact of job demands in nursing homes: a cross-sectional study.

    Science.gov (United States)

    Willemse, Bernadette M; de Jonge, Jan; Smit, Dieneke; Depla, Marja F I A; Pot, Anne Margriet

    2012-07-01

    Healthcare workers in nursing homes are faced with high job demands that can have a detrimental impact on job-related outcomes, such as job satisfaction. Job resources may have a buffering role on this relationship. The Demand-Control-Support (DCS) Model offers a theoretical framework to study how specific job resources can buffer the adverse effects of high demands, and can even activate positive consequences of high demands. The present study tests the moderating (i.e. buffering and activating) effects of decision authority and coworker- and supervisor support that are assumed by the hypotheses of the DCS Model. A national cross-sectional survey was conducted with an anonymous questionnaire. One hundred and thirty six living arrangements that provide nursing home care for people with dementia in the Netherlands. Fifteen healthcare workers per living arrangement. In total, 1147 people filled out the questionnaires (59% response rate). Hierarchical multilevel regression analyses were conducted to test the assumption that the effect of job demands on the dependent variables is buffered or activated the most when both decision authority and social support are high. This moderation is statistically represented by three-way interactions (i.e. demands×authority×support), while lower-order effects are taken into account (i.e. two-way interactions). The hypotheses are supported when three-way interaction effects are found in the expected direction. The dependent variables studied are job satisfaction, emotional exhaustion, and personal accomplishment. The proposed buffering and activation hypotheses of the DCS Model were not supported in our study. Three-way interaction effects were found for emotional exhaustion and personal accomplishment, though not in the expected direction. In addition, two-way interaction effects were found for job satisfaction and emotional exhaustion. Decision authority was found to buffer the adverse effect of job demands and to activate

  7. 78 FR 38023 - Demand Response Supporters v. New York Independent System Operator, Inc.; Notice of Complaint

    Science.gov (United States)

    2013-06-25

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL13-74-000] Demand Response... Practice and Procedure of the Federal Energy Regulatory Commission (Commission), 18 CFR 385.206, Demand..., Inc. (NYISO or Respondents), seeking an order requiring NYISO to amend its tariffs to allow demand...

  8. The effect of alternative work arrangements on women's well-being: a demand-control model.

    Science.gov (United States)

    Kelloway, E K; Gottlieb, B H

    1998-01-01

    The growth of women's participation in the labor force and evidence of the conflict they experience between job and family demands have spurred many employers to introduce alternative work arrangements such as flextime, job sharing, and telecommuting. Drawing on data gained from a sample of women (N = 998) in two large Canadian organizations, this study evaluates two mediational models of the impact of alternative work arrangements on women's stress and family role competence. Specifically, it tests and finds support for the hypotheses that (a) work arrangements involving scheduling flexibility (telecommuting and flextime) promote these aspects of women's well-being by increasing their perceived control over their time, and (b) arrangements involving reduced hours of employment (part-time employment and job sharing) promote well-being by reducing perceived job overload. Discussion of these findings centers on their implications for employed women, their employers, and future research.

  9. An Auto Tuning Substation Peak Shaving Controller for Congestion Management Using Flexible Demand

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Marinelli, Mattia

    2013-01-01

    A closed loop substation peak shaving/congestion management controller for radial distribution networks is presented. The controller it uses an individual control signal in order to shift the consumption of a population of demand side resources, DSRs. The controller auto tunes its parameters on...

  10. Effects of perceived social support and family demands on college students' mental well-being: A cross-cultural investigation

    OpenAIRE

    Khallad, Y.; Jabr, F.

    2015-01-01

    The effects of perceived social support and family demands on college students' mental well-being (perceived stress and depression) were assessed in 2 samples of Jordanian and Turkish college students. Statistically significant negative correlations were found between perceived support and mental well-being. Multiple regression analyses showed that perceived family support was a better predictor of mental well-being for Jordanian students, while perceived support from friends was a better pre...

  11. A Novel Software Platform Extending Advances in Monitoring Technologies to On-demand Decision Support

    Science.gov (United States)

    Ormerod, R.; Scholl, M.

    2017-12-01

    Rapid evolution is occurring in the monitoring and assessment of air emissions and their impacts. The development of next generation lower cost sensor technologies creates the potential for much more intensive and far-reaching monitoring networks that provide spatially rich data. While much attention at present is being directed at the types and performance characteristics of sensor technologies, it is important also that the full potential of rich data sources be realized. Parallel to sensor developments, software platforms to display and manage data in real time are increasingly common adjuncts to sensor networks. However, the full value of data can be realized by extending platform capabilities to include complex scientific functions that are integrated into an action-oriented management framework. Depending on the purpose and nature of a monitoring network, there will be a variety of potential uses of the data or its derivatives, for example: statistical analysis for policy development, event analysis, real-time issue management including emergency response and complaints, and predictive management. Moving these functions into an on-demand, optionally mobile, environment greatly increases the value and accessibility of the data. Increased interplay between monitoring data and decision-making in an operational environment is optimised by a system that is designed with equal weight on technical robustness and user experience. A system now being used by several regulatory agencies and a larger number of industries in the US, Latin America, Europe, Australia and Asia has been developed to provide a wide range of on-demand decision-support in addition to the basic data collection, display and management that most platforms offer. With stable multi-year operation, the platform, known as Envirosuite, is assisting organisations to both reduce operating costs and improve environmental performance. Some current examples of its application across a range of applications

  12. A Decision Support System for Demand Management of the Rio Conchos Basin, Mexico

    Science.gov (United States)

    Stewart, S.; Valdes, J.; Gastelum, J.; Brookshire, D.; Aparicio, J.; Hidalgo, J.; Velazco, I.

    2003-12-01

    There is a need for integrated models of transboundary watersheds such as that of the Rio Grande/Rio Bravo (RGRB) along the US/Mexico border. We present the first stage an interdisciplinary effort to develop a semi-distributed regional dynamic simulation model (DSM) for examining water issues in the Lower RGRB basin. The RGRB serves as the border between the U.S. and Mexico. We focus first on the Conchos River basin, which contributes approximately 70-80% of the surface flow in the lower RGRB basin. Irrigated agriculture has historically been the major user of water and irrigated acreage continues to expand, but it faces increasing competition from industrial development, maquiladoras, and increasing residential water demand. International agreements such as the Treaty of 1944 between the US and Mexico stipulate that the flows in the RGRB are equally split. Yet uncertainties remain due to vagaries in the legislation. For example, Mexico is required to provide an average of 350,000 AF/yr over a five-year cycle, unless "extraordinary drought" occurs, although the Treaty does not define extraordinary. The characterization of droughts poses a significant problem for hydrometeorologists and water resource engineers. Our simulation model incorporates drought indices developed to characterize droughts in semi-arid and arid regions and statistical approaches to examine the spatial influence of droughts. To examine the effects of various structural and institutional changes to water use in the basin to meet the requirements of the Treaty and simulate climactic issues, we model agricultural, municipal, and industrial water demands that are directly linked to sectors of the regional economy using input output (IO) models. IO models can be used to examine how changes in water deliveries to the agricultural or manufacturing sectors affect the level of output, employment, and wages in the regional economy. All model outputs will be incorporated into a decision support system

  13. Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control

    NARCIS (Netherlands)

    de Croon, E. M.; Blonk, R. W. B.; de Zwart, B. C. H.; Frings-Dresen, M. H. W.; Broersen, J. P. J.

    2002-01-01

    Objectives: Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers.

  14. A Relook at the National Drug Control Strategy: Supply versus Demand

    National Research Council Canada - National Science Library

    Cook, Virgil

    1998-01-01

    .... By reviewing the ends, ways, and means of past drug control strategies, this paper suggests that it is time for the federal government to shift existing resources from supply reduction to demand reduction programs...

  15. Effects of perceived social support and family demands on college students' mental well-being: A cross-cultural investigation.

    Science.gov (United States)

    Khallad, Yacoub; Jabr, Fares

    2016-10-01

    The effects of perceived social support and family demands on college students' mental well-being (perceived stress and depression) were assessed in 2 samples of Jordanian and Turkish college students. Statistically significant negative correlations were found between perceived support and mental well-being. Multiple regression analyses showed that perceived family support was a better predictor of mental well-being for Jordanian students, while perceived support from friends was a better predictor of mental well-being for Turkish students. Perceived family demands were stronger predictors of mental well-being for participants from both ethnic groups. Jordanian and Turkish participants who perceived their families to be too demanding were more likely to report higher depression and stress levels. None of the interactions between social support or family demands and either of the 2 demographic variables were statistically significant. These findings provide a more nuanced view of the relationship between social support and mental health among college students, and point to the relevance of some cultural and situational factors. They also draw further attention to the detrimental effects of unrealistic family demands and pressures on the mental health of college youths. © 2015 International Union of Psychological Science.

  16. Mission Planning and Decision Support for Underwater Glider Networks: A Sampling on-Demand Approach

    Science.gov (United States)

    Ferri, Gabriele; Cococcioni, Marco; Alvarez, Alberto

    2015-01-01

    This paper describes an optimal sampling approach to support glider fleet operators and marine scientists during the complex task of planning the missions of fleets of underwater gliders. Optimal sampling, which has gained considerable attention in the last decade, consists in planning the paths of gliders to minimize a specific criterion pertinent to the phenomenon under investigation. Different criteria (e.g., A, G, or E optimality), used in geosciences to obtain an optimum design, lead to different sampling strategies. In particular, the A criterion produces paths for the gliders that minimize the overall level of uncertainty over the area of interest. However, there are commonly operative situations in which the marine scientists may prefer not to minimize the overall uncertainty of a certain area, but instead they may be interested in achieving an acceptable uncertainty sufficient for the scientific or operational needs of the mission. We propose and discuss here an approach named sampling on-demand that explicitly addresses this need. In our approach the user provides an objective map, setting both the amount and the geographic distribution of the uncertainty to be achieved after assimilating the information gathered by the fleet. A novel optimality criterion, called Aη, is proposed and the resulting minimization problem is solved by using a Simulated Annealing based optimizer that takes into account the constraints imposed by the glider navigation features, the desired geometry of the paths and the problems of reachability caused by ocean currents. This planning strategy has been implemented in a Matlab toolbox called SoDDS (Sampling on-Demand and Decision Support). The tool is able to automatically download the ocean fields data from MyOcean repository and also provides graphical user interfaces to ease the input process of mission parameters and targets. The results obtained by running SoDDS on three different scenarios are provided and show that So

  17. Mission Planning and Decision Support for Underwater Glider Networks: A Sampling on-Demand Approach.

    Science.gov (United States)

    Ferri, Gabriele; Cococcioni, Marco; Alvarez, Alberto

    2015-12-26

    This paper describes an optimal sampling approach to support glider fleet operators and marine scientists during the complex task of planning the missions of fleets of underwater gliders. Optimal sampling, which has gained considerable attention in the last decade, consists in planning the paths of gliders to minimize a specific criterion pertinent to the phenomenon under investigation. Different criteria (e.g., A, G, or E optimality), used in geosciences to obtain an optimum design, lead to different sampling strategies. In particular, the A criterion produces paths for the gliders that minimize the overall level of uncertainty over the area of interest. However, there are commonly operative situations in which the marine scientists may prefer not to minimize the overall uncertainty of a certain area, but instead they may be interested in achieving an acceptable uncertainty sufficient for the scientific or operational needs of the mission. We propose and discuss here an approach named sampling on-demand that explicitly addresses this need. In our approach the user provides an objective map, setting both the amount and the geographic distribution of the uncertainty to be achieved after assimilating the information gathered by the fleet. A novel optimality criterion, called A η , is proposed and the resulting minimization problem is solved by using a Simulated Annealing based optimizer that takes into account the constraints imposed by the glider navigation features, the desired geometry of the paths and the problems of reachability caused by ocean currents. This planning strategy has been implemented in a Matlab toolbox called SoDDS (Sampling on-Demand and Decision Support). The tool is able to automatically download the ocean fields data from MyOcean repository and also provides graphical user interfaces to ease the input process of mission parameters and targets. The results obtained by running SoDDS on three different scenarios are provided and show that So

  18. Mission Planning and Decision Support for Underwater Glider Networks: A Sampling on-Demand Approach

    Directory of Open Access Journals (Sweden)

    Gabriele Ferri

    2015-12-01

    Full Text Available This paper describes an optimal sampling approach to support glider fleet operators and marine scientists during the complex task of planning the missions of fleets of underwater gliders. Optimal sampling, which has gained considerable attention in the last decade, consists in planning the paths of gliders to minimize a specific criterion pertinent to the phenomenon under investigation. Different criteria (e.g., A, G, or E optimality, used in geosciences to obtain an optimum design, lead to different sampling strategies. In particular, the A criterion produces paths for the gliders that minimize the overall level of uncertainty over the area of interest. However, there are commonly operative situations in which the marine scientists may prefer not to minimize the overall uncertainty of a certain area, but instead they may be interested in achieving an acceptable uncertainty sufficient for the scientific or operational needs of the mission. We propose and discuss here an approach named sampling on-demand that explicitly addresses this need. In our approach the user provides an objective map, setting both the amount and the geographic distribution of the uncertainty to be achieved after assimilating the information gathered by the fleet. A novel optimality criterion, called A η , is proposed and the resulting minimization problem is solved by using a Simulated Annealing based optimizer that takes into account the constraints imposed by the glider navigation features, the desired geometry of the paths and the problems of reachability caused by ocean currents. This planning strategy has been implemented in a Matlab toolbox called SoDDS (Sampling on-Demand and Decision Support. The tool is able to automatically download the ocean fields data from MyOcean repository and also provides graphical user interfaces to ease the input process of mission parameters and targets. The results obtained by running SoDDS on three different scenarios are provided

  19. 'Demand pull' government policies to support Product-Service System activity: The case of Energy Service Companies in the UK

    OpenAIRE

    Hannon, MJ; Foxon, TJ; Gale, WF

    2015-01-01

    Product-Service Systems (PSSs) constitute a family of service-based business models designed to satisfy our societal needs in an economically and environmentally sustainable manner. To date however PSS application has remained niche due to a variety of critical barriers. This paper explores how ‘demand pull’ national government policies could support PSS activity by addressing these barriers and cultivating market demand. Lessons are drawn from a case study of how regulatory, economic incenti...

  20. On-Demand Final State Control of a Surface-Bound Bistable Single Molecule Switch.

    Science.gov (United States)

    Garrido Torres, José A; Simpson, Grant J; Adams, Christopher J; Früchtl, Herbert A; Schaub, Renald

    2018-04-12

    Modern electronic devices perform their defined action because of the complete reliability of their individual active components (transistors, switches, diodes, and so forth). For instance, to encode basic computer units (bits) an electrical switch can be used. The reliability of the switch ensures that the desired outcome (the component's final state, 0 or 1) can be selected with certainty. No practical data storage device would otherwise exist. This reliability criterion will necessarily need to hold true for future molecular electronics to have the opportunity to emerge as a viable miniaturization alternative to our current silicon-based technology. Molecular electronics target the use of single-molecules to perform the actions of individual electronic components. On-demand final state control over a bistable unimolecular component has therefore been one of the main challenges in the past decade (1-5) but has yet to be achieved. In this Letter, we demonstrate how control of the final state of a surface-supported bistable single molecule switch can be realized. On the basis of the observations and deductions presented here, we further suggest an alternative strategy to achieve final state control in unimolecular bistable switches.

  1. Demanda por grupos, psicologia e controle Group demand, psychology and control

    Directory of Open Access Journals (Sweden)

    Abrahão de Oliveira Santos

    2011-08-01

    Full Text Available Este artigo traz uma reflexão sobre uma capacitação para o trabalho grupal, destinado às equipes das UBSs (Unidades Básica de Saúde do SUS (Sistema Único de Saúde e agentes comunitários de saúde de um município do interior do Estado de São Paulo. Trata-se de analisar o pedido explicitado pela equipe, de mostrar a reflexão a respeito desse pedido, as circunstâncias dos problemas colocados, a experiência dos vários trabalhadores da equipe e a escuta do que se passa do lado da população. Parar para ouvir os parceiros do trabalho e refletir sobre a intervenção fez a equipe trabalhar sua sensibilidade diante das questões da população, do que vem a ser saúde e poder assumir outra postura que não seja a de servir ao controle da população e trabalhar para a construção da sociedade de controle.This article brings a reflection about a training for group work developed with UBSs (Basic Units of Health technical staff from SUS (Unified System of Health and agents of health from a county in the State of São Paulo, Brazil. The procedure involves: (1 to analyze the explicit demand form the crew, (2 to show a reflection about this demand, (3 to show the context of the problems, (4 to consider the experience of workers on the crew, and (5 to listen to what happens from population's standpoint. Stop listening to the job partners and reflecting about the intervention made the crew work.

  2. Using TPO data to estimate timber demand in support of planning on the Tongass National Forest

    Science.gov (United States)

    Jean M. Daniels; Michael D. Paruszkiewicz; Susan J. Alexander

    2015-01-01

    Projections of Alaska timber products output, the derived demand for logs, lumber, residues, and niche products, and timber harvest by owner are developed by using a trend-based analysis. This is the fifth such analysis performed since 1990 to assist planners in meeting statutory requirements for estimating planning cycle demand for timber from the Tongass National...

  3. The Effect of the Demand Control and Effort Reward Imbalance Models on the Academic Burnout of Korean Adolescents

    Science.gov (United States)

    Lee, Jayoung; Puig, Ana; Lee, Sang Min

    2012-01-01

    The purpose of this study was to examine the effects of the Demand Control Model (DCM) and the Effort Reward Imbalance Model (ERIM) on academic burnout for Korean students. Specifically, this study identified the effects of the predictor variables based on DCM and ERIM (i.e., demand, control, effort, reward, Demand Control Ratio, Effort Reward…

  4. Learning to Control Advanced Life Support Systems

    Science.gov (United States)

    Subramanian, Devika

    2004-01-01

    Advanced life support systems have many interacting processes and limited resources. Controlling and optimizing advanced life support systems presents unique challenges. In particular, advanced life support systems are nonlinear coupled dynamical systems and it is difficult for humans to take all interactions into account to design an effective control strategy. In this project. we developed several reinforcement learning controllers that actively explore the space of possible control strategies, guided by rewards from a user specified long term objective function. We evaluated these controllers using a discrete event simulation of an advanced life support system. This simulation, called BioSim, designed by Nasa scientists David Kortenkamp and Scott Bell has multiple, interacting life support modules including crew, food production, air revitalization, water recovery, solid waste incineration and power. They are implemented in a consumer/producer relationship in which certain modules produce resources that are consumed by other modules. Stores hold resources between modules. Control of this simulation is via adjusting flows of resources between modules and into/out of stores. We developed adaptive algorithms that control the flow of resources in BioSim. Our learning algorithms discovered several ingenious strategies for maximizing mission length by controlling the air and water recycling systems as well as crop planting schedules. By exploiting non-linearities in the overall system dynamics, the learned controllers easily out- performed controllers written by human experts. In sum, we accomplished three goals. We (1) developed foundations for learning models of coupled dynamical systems by active exploration of the state space, (2) developed and tested algorithms that learn to efficiently control air and water recycling processes as well as crop scheduling in Biosim, and (3) developed an understanding of the role machine learning in designing control systems for

  5. Value congruence, control, sense of community and demands as determinants of burnout syndrome among hospitality workers.

    Science.gov (United States)

    Asensio-Martínez, Ángela; Leiter, Michael P; Gascón, Santiago; Gumuchian, Stephanie; Masluk, Bárbara; Herrera-Mercadal, Paola; Albesa, Agustín; García-Campayo, Javier

    2017-09-07

    Employees working in the hospitality industry are constantly exposed to occupational stressors that may lead employees into experiencing burnout syndrome. Research addressing the interactive effects of control, community and value congruence to alleviate the impact of workplace demands on experiencing burnout is relatively limited. The present study examined relationships among control, community and value congruence, workplace demands and the three components of burnout. A sample of 418 employees working in a variety of hospitality associations including restaurants and hotels in Spain were recruited. Moderation analyses and linear regressions analyzed the predictive power of control, community and value congruence as moderating variables. Results indicate that control, community and value congruence were successful buffers in the relationships between workplace demands and the burnout dimensions. The present findings offer suggestions for future research on potential moderating variables, as well as implications for reducing burnout among hospitality employees.

  6. Effects of dynamic-demand-control appliances on the power grid frequency

    Science.gov (United States)

    Tchuisseu, E. B. Tchawou; Gomila, D.; Brunner, D.; Colet, P.

    2017-08-01

    Power grid frequency control is a demanding task requiring expensive idle power plants to adapt the supply to the fluctuating demand. An alternative approach is controlling the demand side in such a way that certain appliances modify their operation to adapt to the power availability. This is especially important to achieve a high penetration of renewable energy sources. A number of methods to manage the demand side have been proposed. In this work we focus on dynamic demand control (DDC), where smart appliances can delay their switchings depending on the frequency of the system. We introduce a simple model to study the effects of DDC on the frequency of the power grid. The model includes the power plant equations, a stochastic model for the demand that reproduces, adjusting a single parameter, the statistical properties of frequency fluctuations measured experimentally, and a generic DDC protocol. We find that DDC can reduce small and medium-size fluctuations but it can also increase the probability of observing large frequency peaks due to the necessity of recovering pending task. We also conclude that a deployment of DDC around 30-40% already allows a significant reduction of the fluctuations while keeping the number of pending tasks low.

  7. Work-family conflict and enrichment in nurses: between job demands, perceived organisational support and work-family backlash.

    Science.gov (United States)

    Ghislieri, Chiara; Gatti, Paola; Molino, Monica; Cortese, Claudio G

    2017-01-01

    This study investigated how work relationships (perceived organisational support, supervisor and co-worker work-family backlash) and job demands (workload, emotional dissonance) can interact with work-family conflict and work-family enrichment. Despite the extensive literature on the work-family interface, few studies on the nursing profession have considered the role of job demands and work relationships, focusing on both the positive and negative side of the work-family interface. The study involved a sample of 500 nurses working in an Italian hospital. Hierarchical multiple regression analyses were used to test hypotheses. Analyses showed that work-family conflict has a positive relationship with job demands and supervisor backlash, and a negative relationship with perceived organisational support. Work-family enrichment was found to have a negative relationship with job demands and a positive relationship with perceived organisational support. No significant relationships were found between work-family enrichment and both backlash dimensions. The study confirmed the importance of promoting a balance between job demands and resources in order to create favourable conditions for work-family enrichment and to prevent work-family conflict. The findings suggest that it may be advisable for health-care organisations to invest in measures at individual, team and organisational levels, specifically in training and counselling for nurses and supervisors. © 2016 John Wiley & Sons Ltd.

  8. Information and Communications Systems for Control-by-Price of Distributed Energy Resources and Flexible Demand

    OpenAIRE

    Nyeng, Preben; Østergaard, Jacob

    2011-01-01

    The control-by-price concept fits well with controlling small-scale generation, storage and demand. In this paper, we investigate the required information and communications systems that are needed to realize the control-by-price concept for such units. We first present a proposal for overall infrastructure and subsystem design and secondly focus on the design and implementation of the end-user price-responsive controller, interfaces, and communications. The design and its applicability on ex...

  9. Design and control of precision drop-on-demand herbicide application in agricultural robotics

    OpenAIRE

    Urdal, Frode; Utstumo, Trygve; Vatne, Jan Kåre; Ellingsen, Simen Andreas Ådnøy; Gravdahl, Jan Tommy

    2014-01-01

    This is the author’s final, accepted and refereed manuscript to the article. Drop-on-demand weed control is a field of research within Precision Agriculture, where the herbicide application is controlled down to individual droplets. This paper focuses on the fluid dynamics and electronics design of the droplet dispensing. The droplets are formed through an array of nozzles, controlled by two-way solenoid valves. A much used control circuit for opening and closing a soleno...

  10. A predictive control scheme for real-time demand response applications

    NARCIS (Netherlands)

    Lampropoulos, I.; Baghina, N.G.; Kling, W.L.; Ribeiro, P.F.

    2013-01-01

    In this work, the focus is placed on the proof of concept of a novel control scheme for demand response. The control architecture considers a uniform representation of non-homogeneous distributed energy resources and allows the participation of virtually all system users in electricity markets. The

  11. Impact of California air quality control policies on the use and demand for natural gas

    International Nuclear Information System (INIS)

    Boyd, J.D.

    1992-01-01

    This paper discusses the impact of California's air quality control policies on the use of natural gas. In this paper the author would like to briefly review the regulatory structure for air pollution control in California, summarize the requirement of the California Clean Air Act of 1988, and discuss the impacts of our regulatory programs on the use and demand for natural gas

  12. Management and control of the electrical energy demand; Administracion y control de la demanda de la energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Johnson Controls [Comision Federal de Electricidad (Mexico)

    2005-07-01

    Administrative measures allow a reduction in the energy consumption, but not always in the electrical demand. Control measures allow a reduction in the billing of the electrical demand, but not always in the energy consumption. This is why it is explained in this document what management and control of the electrical demand is, as well as its control strategies, the control alternatives, the billing demand and at the same time graphical representations along with three practical cases on the management of demand in air compressors, air conditioning equipment and in corporative buildings are presented. [Spanish] La aplicacion de las medidas administrativas permite reducir el consumo de energia, pero no siempre la demanda electrica. La aplicacion de medidas de control permiten reducir la demanda electrica facturable, pero no siempre el consumo de energia. Es por eso que en este documento se explica que es la administracion y el control de la demanda electrica, sus estrategias de control, las alternativas de control, la demanda facturable, representaciones graficas y tres casos practicos sobre la administracion de demanda en compresores de aire, la administracion de demanda en aire acondicionado y la administracion de demanda en un edificio corporativo.

  13. A forecast of typhoid conjugate vaccine introduction and demand in typhoid endemic low- and middle-income countries to support vaccine introduction policy and decisions.

    Science.gov (United States)

    Mogasale, Vittal; Ramani, Enusa; Park, Il Yeon; Lee, Jung Seok

    2017-09-02

    A Typhoid Conjugate Vaccine (TCV) is expected to acquire WHO prequalification soon, which will pave the way for its use in many low- and middle-income countries where typhoid fever is endemic. Thus it is critical to forecast future vaccine demand to ensure supply meets demand, and to facilitate vaccine policy and introduction planning. We forecasted introduction dates for countries based on specific criteria and estimated vaccine demand by year for defined vaccination strategies in 2 scenarios: rapid vaccine introduction and slow vaccine introduction. In the rapid introduction scenario, we forecasted 17 countries and India introducing TCV in the first 5 y of the vaccine's availability while in the slow introduction scenario we forecasted 4 countries and India introducing TCV in the same time period. If the vaccine is targeting infants in high-risk populations as a routine single dose, the vaccine demand peaks around 40 million doses per year under the rapid introduction scenario. Similarly, if the vaccine is targeting infants in the general population as a routine single dose, the vaccine demand increases to 160 million doses per year under the rapid introduction scenario. The demand forecast projected here is an upper bound estimate of vaccine demand, where actual demand depends on various factors such as country priorities, actual vaccine introduction, vaccination strategies, Gavi financing, costs, and overall product profile. Considering the potential role of TCV in typhoid control globally; manufacturers, policymakers, donors and financing bodies should work together to ensure vaccine access through sufficient production capacity, early WHO prequalification of the vaccine, continued Gavi financing and supportive policy.

  14. Effects of externally rated job demand and control on depression diagnosis claims in an industrial cohort.

    Science.gov (United States)

    DeSanto Iennaco, Joanne; Cullen, Mark R; Cantley, Linda; Slade, Martin D; Fiellin, Martha; Kasl, Stanislav V

    2010-02-01

    This study examined whether externally rated job demand and control were associated with depression diagnosis claims in a heavy industrial cohort. The retrospective cohort sample consisted of 7,566 hourly workers aged 18-64 years who were actively employed at 11 US plants between January 1, 1996, and December 31, 2003, and free of depression diagnosis claims during an initial 2-year run-in period. Logistic regression analysis was used to model the effect of tertiles of demand and control exposure on depression diagnosis claims. Demand had a significant positive association with depression diagnosis claims in bivariate models and models adjusted for demographic (age, gender, race, education, job grade, tenure) and lifestyle (smoking status, body mass index, cholesterol level) variables (high demand odds ratio = 1.39, 95% confidence interval: 1.04, 1.86). Control was associated with greater risk of depression diagnosis at moderate levels in unadjusted models only (odds ratio = 1.47, 95% confidence interval: 1.12, 1.93), while low control, contrary to expectation, was not associated with depression. The effects of the externally rated demand exposure were lost with adjustment for location. This may reflect differences in measurement or classification of exposure, differences in depression diagnosis by location, or other location-specific factors.

  15. Job demands and decision control predicted return to work: the rapid-RTW cohort study

    Directory of Open Access Journals (Sweden)

    Lise Aasen Haveraaen

    2017-02-01

    Full Text Available Abstract Background In order to help workers with long-term sickness absence return to work (RTW, it is important to understand factors that either impede or facilitate employee’s reintegration into the labour force. The aim of this study was therefore to examine the impact of psychological work characteristics on time-to first RTW in sick listed employees in Norway. Methods The study was designed as a cohort study of 543 employees participating in 50 different RTW programmes. The Job Content Questionnaire (JCQ was used to gather information on the psychological work conditions. The participants were followed for up to 18 months after they started treatment in the RTW programme. Survival analyses were used to investigate the association between psychological work conditions and time-to first RTW. Results Having high psychological job demands (HR = .654; 95% CI: .513–.832 and low decision control (HR = 1.297; 95% CI: 1.010–1.666 were both independent predictors of delayed RTW. Employees in low-strain jobs (low demands/high control (HR = 1.811; 95% CI: 1.287–2.549 and passive jobs (low demands/low control (HR = 1.599; 95% CI: 1.107–2.309, returned to work earlier compared to employees in high-strain jobs (high demands/low control. No difference was found for active jobs (high demands/high control. Conclusion This study revealed that high psychological demands, low control, and being in a high strain job reduced the probability of early RTW in sick listed employees. RTW programmes should therefore increase the focus on these issues.

  16. Job demands and decision control predicted return to work: the rapid-RTW cohort study.

    Science.gov (United States)

    Haveraaen, Lise Aasen; Skarpaas, Lisebet Skeie; Aas, Randi Wågø

    2017-02-02

    In order to help workers with long-term sickness absence return to work (RTW), it is important to understand factors that either impede or facilitate employee's reintegration into the labour force. The aim of this study was therefore to examine the impact of psychological work characteristics on time-to first RTW in sick listed employees in Norway. The study was designed as a cohort study of 543 employees participating in 50 different RTW programmes. The Job Content Questionnaire (JCQ) was used to gather information on the psychological work conditions. The participants were followed for up to 18 months after they started treatment in the RTW programme. Survival analyses were used to investigate the association between psychological work conditions and time-to first RTW. Having high psychological job demands (HR = .654; 95% CI: .513-.832) and low decision control (HR = 1.297; 95% CI: 1.010-1.666) were both independent predictors of delayed RTW. Employees in low-strain jobs (low demands/high control) (HR = 1.811; 95% CI: 1.287-2.549) and passive jobs (low demands/low control) (HR = 1.599; 95% CI: 1.107-2.309), returned to work earlier compared to employees in high-strain jobs (high demands/low control). No difference was found for active jobs (high demands/high control). This study revealed that high psychological demands, low control, and being in a high strain job reduced the probability of early RTW in sick listed employees. RTW programmes should therefore increase the focus on these issues.

  17. Linking meters and markets: Roles and incentives to support a flexible demand side

    DEFF Research Database (Denmark)

    Katz, Jonas

    2014-01-01

    wholesale market participants to the demand side is mostly infeasible, resulting in flexibility tasks being aggregated and delegated to balancing responsible wholesale traders. This analysis focuses on whether current incentives and roles are appropriate and where the design could be improved to establish......Present trends in the development of electricity systems are expected to generate a growing need for flexibility in decentralised resources, including demand response. In order to enable decentralised actors to create value, the organisation of markets and incentives should incorporate these new...... a flexible demand side with a particular focus on the Danish case. Design-related barriers are identified that affect expected value, associated risks, and the distribution of responsibilities. This serves as a basis to define policy options in the context of Nordic electricity markets. © 2014 Elsevier Ltd...

  18. Prediction of Tourism Demand in Iran by Using Artificial Neural Network (ANN and Supporting Vector Machine (SVR

    Directory of Open Access Journals (Sweden)

    Seyedehelham Sadatiseyedmahalleh

    2016-02-01

    Full Text Available This research examines and proves this effectiveness connected with artificial neural networks (ANNs as an alternative approach to the use of Support Vector Machine (SVR in the tourism research. This method can be used for the tourism industry to define the turism’s demands in Iran. The outcome reveals the use of ANNs in tourism research might result in better quotations when it comes to prediction bias and accuracy. Even more applications of ANNs in the context of tourism demand evaluation is needed to establish and validate the effects.

  19. Overvoltage Mitigation Using Coordinated Control of Demand Response and Grid-tied Photovoltaics

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

    2015-01-01

    Overvoltages in low voltage distribution grids with high solar photovoltaic (PV) integration are usually alleviated by implementing various active/reactive power control techniques. As those methods create revenue loss or inverter cost increase to PV owners, a coordinated control of load demand...... and the PVs, considering electric vehicles (EVs) as potential demand response resource, is proposed in this study to alleviate the overvoltages. A two-stage control is designed to comprehend the proposed coordinated control such that a centralized stage periodically determines optimum operating set......-points for PVs/EVs and a decentralized stage adaptively control the PVs/EVs in real-time. To demonstrate effectiveness of the proposed approach, simulations are performed in a typical 0.4 kV/400 kVA Danish distribution network containing 45 detached residential consumers. The presented method demonstrates better...

  20. Smart Demand for Improving Short-term Voltage Control on Distribution Networks

    DEFF Research Database (Denmark)

    Garcia-Valle, Rodrigo; P. Da Silva, Luiz C.; Xu, Zhao

    2009-01-01

    customer integration to aid power system performance is almost inevitable. This study introduces a new type of smart demand side technology, denoted demand as voltage controlled reserve (DVR), to improve short-term voltage control, where customers are expected to play a more dynamic role to improve voltage...... control. The technology can be provided by thermostatically controlled loads as well as other types of load. This technology is proven to be effective in case of distribution systems with a large composition of induction motors, where the voltage presents a slow recovery characteristic due to deceleration...... of the motors during faults. This study presents detailed models, discussion and simulation tests to demonstrate the technical viability and effectiveness of the DVR technology for short-term voltage control....

  1. Family Demands, Social Support and Family Functioning in Taiwanese Families Rearing Children with Down Syndrome

    Science.gov (United States)

    Hsiao, C-Y.

    2014-01-01

    Background: Down syndrome (DS) affects not only children but also their families. Much remains to be learned about factors that influence how families of children with DS function, especially families in non-Western populations. The purpose of this cross-sectional, correlational study was to examine how family demographics, family demands and…

  2. Job control and coworker support improve employee job performance.

    Science.gov (United States)

    Nagami, Makiko; Tsutsumi, Akizumi; Tsuchiya, Masao; Morimoto, Kanehisa

    2010-01-01

    We examined the prospective association of psychosocial job characteristics with employee job performance among 777 full-time employees at a manufacturing company in Japan, using data from a one-year follow-up survey. Psychosocial job characteristics were measured by the Job Content Questionnaire in 2008; job performance was evaluated using the item from the World Mental Health Survey Instrument in 2008 and 2009. The association between psychosocial job characteristics and job performance was tested using multiple regression analysis, controlling for demographic variables, work status, average working hours per day, job type and job performance in 2008. Job control and coworker support in 2008 were positively related to job performance in 2009. Stratified analyses revealed that job control for staff and coworker support for managers were positively related to job performance in 2009. These associations were prominent among men; however, supervisor support in 2008 was negatively related to job performance in 2009 among men. Job demand was not significantly related to job performance. Our findings suggest that it is worthwhile to enhance employees' job control and provide a mutually supportive environment to ensure positive employee job performance.

  3. An inventory control project in a major Danish company using compound renewal demand models

    DEFF Research Database (Denmark)

    Larsen, Christian; Seiding, Claus Hoe; Teller, Christian

    2008-01-01

    procedures for determining suitable inventory control variables based on the fitted demand distributions and a service-level requirement stated in terms of an order fill rate. Finally, we validated the results of our models against the procedures that had been in use in the company. It was concluded...

  4. Demand controllers with optimized programing; Controladores de demanda com programacao otimizada

    Energy Technology Data Exchange (ETDEWEB)

    Santos, A.H.M.; Haddad, J.; Almeida, A.T.L. [Escola Federal de Engenharia de Itajuba, MG (Brazil); Devienne, R.F. [Universidade de Taubate (UNITAU), SP (Brazil)

    1995-12-31

    This work presents a methodological proposal for load re-allocation strategy in opposition to the empiric methodology presently used by demand controllers. Through the utilization of dynamic programing techniques associated to fuzzy theory it is possible to modulate the electric power consumers load curve, incorporating different objectives resulting in the global energy consumption rationing 6 figs., 5 tabs., 8 refs.

  5. Burnout and engagement at work as a function of demands and control

    NARCIS (Netherlands)

    Demerouti, E.; Bakker, A.B.; Jonge, J. de; Janssen, P.P.M.; Schaufeli, W.B.

    2001-01-01

    Objectives The present study was designed to test the demand-control model using indicators of both health impairment and active learning or motivation. Methods A total of 381 insurance company employees participated in the study. Discriminant analysis was used to examine the relationship between

  6. Interactive Effects of Emotional Dissonance and Self-Control Demands on Burnout, Anxiety, and Absenteeism

    Science.gov (United States)

    Diestel, Stefan; Schmidt, Klaus-Helmut

    2010-01-01

    Two specific sources of stress at work have recently received increasing attention in organizational stress research: emotional dissonance (ED) and self-control demands (SCDs). Both theoretical arguments and experimental findings in basic research strongly suggest that ED and different SCDs draw on a common limited regulatory resource.…

  7. Predicting and Explaining Students' Stress with the Demand-Control Model: Does Neuroticism Also Matter?

    Science.gov (United States)

    Schmidt, Laura I.; Sieverding, Monika; Scheiter, Fabian; Obergfell, Julia

    2015-01-01

    University students often report high stress levels, and studies even suggest a recent increase. However, there is a lack of theoretically based research on the structural conditions that influence students' perceived stress. The current study compared the effects of Karasek's demand-control dimensions with the influence of neuroticism to address…

  8. Exact Fill Rates for (R, s, S) Inventory Control With Gamma Distributed Demand

    NARCIS (Netherlands)

    Moors, J.J.A.; Strijbosch, L.W.G.

    2001-01-01

    For the familiar (R; s; S) inventory control system only approximate expressions exist for the fill rate, i.e. the fraction of demand that can be satisfied from stock.Best-known are the approximations derived from renewal theory by Tijms & Groenevelt (1984), holding under specific conditions; in

  9. An up-link power control for demand assignment International Business Satellite Communications Network

    Science.gov (United States)

    Nohara, Mitsuo; Takeuchi, Yoshio; Takahata, Fumio

    Up-link power control (UPC) is one of the essential technologies to provide efficient satellite communication systems operated at frequency bands above 10 GHz. A simple and cost-effective UPC scheme applicable to a demand assignment international business satellite communications system has been developed. This paper presents the UPC scheme, including the hardware implementation and its performance.

  10. Dynamic Behaviour of a Population of Controlled-by-price Demand Side Resources

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Han, Xue; Bindner, Henrik W.

    2014-01-01

    It is described that controlling or shedding by price the power consumption of a population of thermostatic loads introduces in the aggregate consumption dynamic effects th at cannot be disregarded if electrical flexible demand is meant to supply power system services. It is shown that inducing...

  11. Demand management through centralized control system using power line communication for existing buildings

    International Nuclear Information System (INIS)

    Al-Mulla, A.; ElSherbini, A.

    2014-01-01

    Highlights: • A pilot system was developed for demand management of equipment in buildings. • The networking was based on LonWorks platform and power line communication. • Demand strategies led to load reductions up to 74% and energy savings up to 25%. • The peak load reduction is expected to reach 3.44 GW by the year 2030. - Abstract: Managing peak demand efficiently is vital for maintaining uninterrupted supply of electrical power by utility providers. In this work, a pilot system was developed for managing and controlling the demand of major power consuming equipment in buildings from a central server, while relying mostly on existing infrastructure and maintaining consumer comfort. The system was successfully demonstrated on a selected group of buildings using the LonWorks networking platform. At the building level, the system utilized power line and twisted pair communication to control the thermostats of air-conditioning (A/C) units. The higher level communication was executed through extensible markup language (XML) and simple object access protocol (SOAP). The system provided control capabilities based on A/C unit priority, thermostat temperature, building type and geographic location. The development and execution of demand management strategies for selected buildings led to peak load reductions up to 74%, in addition to energy savings up to 25%. Implementing such a system at a national level in Kuwait is estimated to reduce peak demand by 3.44 GW, amounting to capital savings of $4.13 billion. The use of existing infrastructure reduced the cost and installation time of the system. Based on the successful testing of this pilot system, a larger-scale system is being developed

  12. Different Optimal Control Strategies for Exploitation of Demand Response in the Smart Grid

    DEFF Research Database (Denmark)

    Zong, Yi; Bindner, Henrik W.; Gehrke, Oliver

    2012-01-01

    To achieve a Danish energy supply based on 100% renewable energy from combinations of wind, biomass, wave and solar power in 2050 and to cover 50% of the Danish electricity consumption by wind power in 2025, it requires coordinated management of large numbers of distributed and demand response...... resources, intermittent renewable energy resources in the Smart Grid. This paper presents different optimal control (Genetic Algorithm-based and Model Predictive Control-based) algorithms that schedule controlled loads in the industrial and residential sectors, based on dynamic price and weather forecast......, considering users’ comfort settings to meet an optimization objective, such as maximum profit or minimum energy consumption. It is demonstrated in this work that the GA-based and MPC-based optimal control strategies are able to achieve load shifting for grid reliability and energy savings, including demand...

  13. Supporting multiple control systems at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Nicklaus, Dennis J.; /Fermilab

    2009-10-01

    The Fermilab control system, ACNET, is used for controlling the Tevatron and all of its pre-accelerators. However, other smaller experiments at Fermilab have been using different controls systems, in particular DOOCS and EPICS. This paper reports some of the steps taken at Fermilab to integrate support for these outside systems. We will describe specific tools that we have built or adapted to facilitate interaction between the architectures. We also examine some of the difficulties that arise from managing this heterogeneous environment. Incompatibilities as well as common elements will be described.

  14. Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control.

    Science.gov (United States)

    de Croon, E M; Blonk, R W B; de Zwart, B C H; Frings-Dresen, M H W; Broersen, J P J

    2002-06-01

    Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work.

  15. Learning and strain among newcomers: a three-wave study on the effects of job demands and job control.

    Science.gov (United States)

    Taris, Toon W; Feij, Jan A

    2004-11-01

    The present 3-wave longitudinal study was an examination of job-related learning and strain as a function of job demand and job control. The participants were 311 newcomers to their jobs. On the basis of R. A. Karasek and T. Theorell's (1990) demand-control model, the authors predicted that high demand and high job control would lead to high levels of learning; low demand and low job control should lead to low levels of learning; high demand and low job control should lead to high levels of strain; and low demand and high job control should lead to low levels of strain. The relation between strain and learning was also examined. The authors tested the hypotheses using ANCOVA and structural equation modeling. The results revealed that high levels of strain have an adverse effect on learning; the reverse effect was not confirmed. It appears that Karasek and Theorell's model is very relevant when examining work socialization processes.

  16. Demand response with locational dynamic pricing to support the integration of renewables

    International Nuclear Information System (INIS)

    Dupont, B.; De Jonghe, C.; Olmos, L.; Belmans, R.

    2014-01-01

    Electricity production from centralised and decentralised renewable energy resources in Europe is gaining significance, resulting in operational challenges in the electricity system. Although these challenges add to the locational and time dependency of the underlying cost of operating the system, this variability in time and location is not reflected in residential tariff schemes. Consequently, residential users are not incentivised to react to varying system conditions and to help the integration of renewable energy resources. Therefore, this paper provides a theoretical framework for designing a locational dynamic pricing scheme. This can be used to assess existing tariff structures for consumption and injection, and can serve as a theoretical background for developing new tariff schemes. Starting from the underlying costs, this paper shows that the potential for locational dynamic pricing depends on the locational and time dependency of its cost drivers. When converting costs into tariffs, the tariff design should be determined. This includes the advance notice of sending tariffs to users, and the length of price blocks and price patterns. This tariff design should find a balance between tariff principles related to costs, practicality and social acceptability on the one hand, and the resulting demand response incentive on the other. - Highlights: • The integration of renewables affects the locational and time dependency of costs. • Locational dynamic pricing reflects cost variability and allows demand response. • A theoretical framework for designing and assessing tariff schemes is proposed. • Tariff variability depends on the locational and time dependency of its cost drivers. • The tariff design should consider the resulting demand response incentive

  17. Online AMR Domestic Load Profile Characteristic Change Monitor to Support Ancillary Demand Services

    DEFF Research Database (Denmark)

    Stephen, Bruce; Isleifsson, Fridrik Rafn; Galloway, Stuart

    2014-01-01

    of small loads is presented. This would allow them to be assessed for their availability to provide demand services to the grid. In the method presented, significant changes in behavior are detected using Bayesian changepoint analysis which tracks a multivariate Gaussian representation of a residential...... in remote rural communities, are currently modeled with homogenous and coarse load profiles developed from aggregated data. An objective of AMR deployment is to clarify the nature and variability of the residential LV customer. In this paper, an algorithm for tracking the consistency of the behavior...

  18. Control rod supporting device in reactor

    International Nuclear Information System (INIS)

    Seki, Osamu; Itooka, Satoshi; Harada, Kiyoshi; Jodoi, Takashi.

    1990-01-01

    Since coolants flowing from a reactor core hit against a control rod and a control rod connection pipe, a considerable amount of bending moment for separating an attracting surface between an electromagnet and an armature is formed. Then, a plurality of grooves are formed on a heat sensitive material to dispose a heat collecting fin, and each of upper and lower contact portions of a control rod supporting portion in which the flanged portion of T-like cross section does not slip out is made into a partial spheric surface and a portion between the electromagnet and the attracted member are engaged by the unevenness. With such a constitution, even if a bending moment is applied, the control rod only swings and the bending moment is not transmitted to the attracted member. Further, since the temperature of the heat sensitive material can be rapidly made closer to the peripheral temperature by using the heat collecting fin, the timing for separation is made accurate. Further, since the engaging portion is brought into contact at the spheric surface, the load distribution on the control rod is made uniform, and the positional relationship is made accurate, to support the control rod reliably and the separation depends only on the temperature of the coolants. (N.H.)

  19. Determinants of nurses' job satisfaction: the role of work-family conflict, job demand, emotional charge and social support.

    Science.gov (United States)

    Cortese, Claudio G; Colombo, Lara; Ghislieri, Chiara

    2010-01-01

    The aim of the present study was to develop a research model explaining the causal relationship between certain antecedents (job and emotional charge, supportive management and colleagues), work-family conflict (WFC) and job satisfaction. Many research projects in health organizations have highlighted the link between high WFC and lower levels of job satisfaction. The study of these variables is important in understanding the processes of professional nurse retention. The survey was conducted using a questionnaire administered to 351 professional nurses working in a major North Italian hospital. The questionnaire measures six variables: WFC, job satisfaction, job demand, emotional charge, supportive management and supportive colleagues. The data confirmed the connection between WFC and job satisfaction, and showed the importance of some WFC predictors, such as supportive management, emotional charge and job demand, not only for their connections with WFC but also for their direct associations with job satisfaction. WFC, in health organizations, can contribute to a decrease of nurses' job satisfaction. Nursing management could achieve its aim of reducing WFC through the improvement of support from nurse coordinators, the specific organization of work models, ad hoc family-friendly policies and individual counselling programmes for nurses.

  20. Employer-Supported Training in Australia: Participation, Demand and Supply. NCVER Technical Report

    Science.gov (United States)

    Shah, Chandra

    2017-01-01

    This report provides an analysis of employer-supported training in Australia. Employer-supported training is the largest share of adult education and training in all Organisation for Economic Co-operation and Development (OECD) countries. It has benefits for individuals, firms, and society. Cross-country studies have shown a positive association…

  1. Control Scheme Formulation for the Production of Hydrogen on Demand to Feed an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Jarniel García Morales

    2016-12-01

    Full Text Available In this work, a control strategy is presented to produce hydrogen on demand to feed an internal combustion (IC engine. For this purpose, the modeling of the IC engine fueled by gasoline blended with 10 % v/v of anhydrous ethanol (E10 and hydrogen as an additive is developed. It is considered that the hydrogen gas is produced according to the IC engine demand, and that the hydrogen gas is obtained by an alkaline electrolyzer. The gasoline–ethanol blend added into the combustion chamber is determined according to the stoichiometric ratio and the production of hydrogen gas is regulated by a proportional and integral controller (P.I.. The controller reference is varying according to the mass flow air induced into the cylinder, in order to ensure an adequate production of hydrogen gas for any operating condition of the IC engine. The main contribution of this work is the control scheme developed, through simulation, in order to produce hydrogen on demand for any operating point of an internal combustion engine fueled by an E10 blend. The simulation results showed that the use of hydrogen gas as an additive in an E10 blend decreases the E10 fuel consumption 23 % on average, and the thermal efficiency is increased approximately 2.13 % , without brake power loss in the IC engine.

  2. The supply and demand for pollution control: Evidence from wastewater treatment

    Science.gov (United States)

    McConnell, V.D.; Schwarz, G.E.

    1992-01-01

    This paper analyzes the determination of pollution control from wastewater treatment plants as an economic decision facing local or regional regulators. Pollution control is measured by plant design effluent concentration levels and is fully endogenous in a supply- and-demand model of treatment choice. On the supply side, plant costs are a function of the design treatment level of the plant, and on the demand side, treatment level is a function of both the costs of control and the regional or regulatory preferences for control. We find evidence that the economic model of effluent choice by local regulators has a good deal of explanatory power. We find evidence that wastewater treatment plant removal of biological oxygen demand (BOD) is sensitive to many local factors including the size of the treatment plant, the flow rate of the receiving water, the population density of the surrounding area, regional growth, state sensitivity to environmental issues, state income, and the extent to which the damages from pollution fall on other states. We find strong evidence that regulators are sensitive to capital costs in determining the design level of BOD effluent reduction at a plant. Thus, proposed reductions in federal subsidies for wastewater treatment plant construction are likely to have significant adverse effects on water quality. ?? 1992.

  3. Energy efficient ventilation based on demand humidity control. Demonstration project with 49 apartments in Soenderborg

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The aim of the project is to demonstrate how the overall energy consumption in apartment buildings can be reduced through a combination of: 1) Energy efficient ventilation based on demand humidity control; 2) Energy efficient design of the building shell including passive solar and seasonally flexible sunspaces; 3) Use of low temperature heating system. The 3 blocks in the project, each with 16 apartments, are furnished with 3 different ventilation systems: 1) Standard exhaust system according to building codes; 2) Ventilation system with humidity control. Each room is furnished with an air inlet valve controlled by a processor, which monitors the humidity; 3) Standard ventilation system with heat recovery. (au)

  4. Hardware-in-the-loop (HIL) Test of Demand as Frequency Controlled Reserve (DFR)

    DEFF Research Database (Denmark)

    Wu, Qiuwei; Zimmermann, K.; Østergaard, Jacob

    2016-01-01

    This paper presents the hardware-in-the-loop (HIL) test of the demand as frequency controlled reserve (DFR). The HIL test refers to a test in which parts of a pure simulation have been replaced by actual physical components. It is used to understand the behavior of a new device or controller....... The DFR has been tested by offline simulations to illustrate the efficacy of this technology. The DFR control logics have been implemented in the SmartBox. The HIL was conducted by having the SmartBox connected to the real time simulations and the performance of the SmartBox was tested with difference...

  5. On Inventory Control For Perishable Inventory Systems Subject To Uncertainties On Customer Demands

    OpenAIRE

    Abbou , Rosa; Loiseau , Jean-Jacques; Khaldi , Hajer; Farraa , Berna ,

    2017-01-01

    International audience; This paper deals with the inventory controller design for constrained production systems subject to uncertainties on the customer demands. The case study focuses on the inventory regulation problem in production systems where contain perishable finite products. Such systems are characterized by the presence of delays due to production processes, and constraints from the instantaneous inventory level, production level and the finite capacities of stocks. To do that, we ...

  6. Accumulative job demands and support for strength use : Fine-tuning the job demands-resources model using conservation of resources theory

    NARCIS (Netherlands)

    van Woerkom, M.; Bakker, A.B.; Nishii, L.H.

    2016-01-01

    Absenteeism associated with accumulated job demands is a ubiquitous problem. We build on prior research on the benefits of counteracting job demands with resources by focusing on a still untapped resource for buffering job demands—that of strengths use. We test the idea that employees who are

  7. Controlling market power and price spikes in electricity networks: Demand-side bidding.

    Science.gov (United States)

    Rassenti, Stephen J; Smith, Vernon L; Wilson, Bart J

    2003-03-04

    In this article we report an experiment that examines how demand-side bidding can discipline generators in a market for electric power. First we develop a treatment without demand-side bidding; two large firms are allocated baseload and intermediate cost generators such that either firm might unilaterally withhold the capacity of its intermediate cost generators from the market to benefit from the supracompetitive prices that would result from only selling its baseload units. In a converse treatment, ownership of some of the intermediate cost generators is transferred from each of these firms to two other firms such that no one firm could unilaterally restrict output to spawn supracompetitive prices. Having established a well controlled data set with price spikes paralleling those observed in the naturally occurring economy, we also extend the design to include demand-side bidding. We find that demand-side bidding completely neutralizes the exercise of market power and eliminates price spikes even in the presence of structural market power.

  8. The nature of mind wandering during reading varies with the cognitive control demands of the reading strategy.

    Science.gov (United States)

    Moss, Jarrod; Schunn, Christian D; Schneider, Walter; McNamara, Danielle S

    2013-11-20

    Prior studies of mind wandering find the default network active during mind wandering, but these studies have yielded mixed results concerning the role of cognitive control brain regions during mind wandering. Mind wandering often interferes with reading comprehension, and prior neuroimaging studies of discourse comprehension and strategic reading comprehension have shown that there are at least two networks of brain regions that support strategic discourse comprehension: a domain-general control network and a network of regions supporting coherence-building comprehension processes. The present study was designed to further examine the neural correlates of mind wandering by examining mind wandering during strategic reading comprehension. Participants provided ratings of mind wandering frequency that were used to investigate interactions between the strategy being performed and brain regions whose activation was modulated by wind wandering. The results support prior findings showing that cognitive control regions are at times more active during mind wandering than during a task with low control demands, such as rereading. This result provides an initial examination of the neural correlates of mind wandering during discourse comprehension and shows that the processes being engaged by the primary task need to be considered when studying mind wandering. The results also replicate, in a different learning domain, prior findings of key brain areas associated with different reading strategies. © 2013 Published by Elsevier B.V.

  9. Job control and social support as coping resources in job satisfaction.

    Science.gov (United States)

    Shimazu, Akihito; Shimazu, Miyuki; Odahara, Tsutomu

    2004-04-01

    This study examined the effects of active coping on job satisfaction in the context of the job demands-control-support model. Participants were 867 employees (811 men and 56 women, M age = 35.2 yr.) of a large electrical company in Japan. Hierarchical multiple regression analysis examined whether effects of active coping on job satisfaction might depend on the extent of coping resources, such as job control or social support (supervisor and coworker). Analysis showed that the effect of active coping on job satisfaction depended on the extent of coworkers' support, not on job control and supervisors' support.

  10. Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices

    Science.gov (United States)

    Chassin, David P [Pasco, WA; Donnelly, Matthew K [Kennewick, WA; Dagle, Jeffery E [Richland, WA

    2011-12-06

    Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

  11. Eldercare Demands, Strain, and Work Engagement: The Moderating Role of Perceived Organizational Support

    Science.gov (United States)

    Zacher, Hannes; Winter, Gabriele

    2011-01-01

    Demographic changes give rise to an increasing number of middle-aged employees providing home-based care to an elderly family member. However, the potentially important role of employees' perceptions of organizational support for eldercare has so far not been investigated. The goal of this study was to examine a stressor-strain-outcome model…

  12. Eldercare demands, strain, and work engagement : The moderating role of perceived organizational support

    NARCIS (Netherlands)

    Zacher, Hannes; Winter, Gabriele

    2011-01-01

    Demographic changes give rise to an increasing number of middle-aged employees providing home-based care to an elderly family member. However, the potentially important role of employees perceptions of organizational support for eldercare has so far not been investigated. The goal of this study was

  13. A hard day's night : a longitudinal study on the relationships among job demands and job control, sleep quality and fatigue

    NARCIS (Netherlands)

    De Lange, Annet H.; Kompier, Michiel A. J.; Taris, Toon W.; Geurts, Sabine A. E.; Beckers, Debby G. J.; Houtman, Irene L. D.; Bongers, Paulien M.

    This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand-control history on the development of sleep quality and fatigue. Based on results of a

  14. A hard day's night: a longitudinal study on the relationships among job demands and job control, sleep quality and fatigue

    NARCIS (Netherlands)

    Lange, A.H. de; Kompier, M.A.J.; Taris, T.W.; Geurts, S.A.E.; Beckers, D.G.J.; Houtman, I.L.D.; Bongers, P.M.

    2009-01-01

    This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand-control history on the development of sleep quality and fatigue. Based on results of a

  15. A hard day's night: a longitudinal study on the relationships among job demands and job control, sleep quality and fatigue

    NARCIS (Netherlands)

    de Lange, A.H.; Kompier, M.A.J.; Taris, T.W.; Geurts, S.A.E.; Beckers, D.G.J.; Houtman, I.L.H.; Bongers, P.M.

    2009-01-01

    Summary This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand-control history on the development of sleep quality and fatigue. Based on results

  16. A hard day's night: A longitudinal study on the relationships among job demands and job control, sleep quality and fatigue

    NARCIS (Netherlands)

    Lange, A.H.de; Kompier, M.A.J.; Taris, T.W.; Geurts, S.A.E.; Beckers, D.G.J.; Houtman, I.L.D.; Bongers, P.M.

    2009-01-01

    This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand-control history on the development of sleep quality and fatigue. Based on results of a

  17. Learning and strain among newcomers: a three-wave study on the effects of Job Demands and Job Control

    NARCIS (Netherlands)

    Taris, T.W.; Feij, J.A.

    2004-01-01

    The present 3-wave longitudinal study was an examination of job-related learning and strain as a function of job demand and job control. The participants were 311 newcomers to their jobs. On the basis of R. A. Karasek and T. Theorell's (1990) demand-control model, the authors predicted that high

  18. Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control

    NARCIS (Netherlands)

    Croon, E.M. de; Blonk, R.W.B.; Zwart, B.C.H. de; Frings-Dresen, M.H.W.; Broersen, J.P.J.

    2002-01-01

    Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands on fatigue and job dissatisfaction in Dutch lorry drivers. From 1181 lorry drivers self reported information was

  19. Controllable deterioration rate for time-dependent demand and time-varying holding cost

    Directory of Open Access Journals (Sweden)

    Mishra Vinod Kumar

    2014-01-01

    Full Text Available In this paper, we develop an inventory model for non-instantaneous deteriorating items under the consideration of the facts: deterioration rate can be controlled by using the preservation technology (PT during deteriorating period, and holding cost and demand rate both are linear function of time, which was treated as constant in most of the deteriorating inventory models. So in this paper, we developed a deterministic inventory model for non-instantaneous deteriorating items in which both demand rate and holding cost are a linear function of time, deterioration rate is constant, backlogging rate is variable and depend on the length of the next replenishment, shortages are allowed and partially backlogged. The model is solved analytically by minimizing the total cost of the inventory system. The model can be applied to optimizing the total inventory cost of non-instantaneous deteriorating items inventory for the business enterprises, where the preservation technology is used to control the deterioration rate, and demand & holding cost both are a linear function of time.

  20. Multi-Time Scale Control of Demand Flexibility in Smart Distribution Networks

    Directory of Open Access Journals (Sweden)

    Bishnu P. Bhattarai

    2017-01-01

    Full Text Available This paper presents a multi-timescale control strategy to deploy electric vehicle (EV demand flexibility for simultaneously providing power balancing, grid congestion management, and economic benefits to participating actors. First, an EV charging problem is investigated from consumer, aggregator, and distribution system operator’s perspectives. A hierarchical control architecture (HCA comprising scheduling, coordinative, and adaptive layers is then designed to realize their coordinative goal. This is realized by integrating multi-time scale controls that work from a day-ahead scheduling up to real-time adaptive control. The performance of the developed method is investigated with high EV penetration in a typical residential distribution grid. The simulation results demonstrate that HCA efficiently utilizes demand flexibility stemming from EVs to solve grid unbalancing and congestions with simultaneous maximization of economic benefits to the participating actors. This is ensured by enabling EV participation in day-ahead, balancing, and regulation markets. For the given network configuration and pricing structure, HCA ensures the EV owners to get paid up to five times the cost they were paying without control.

  1. Flexible Demand Control to Enhance the Dynamic Operation of Low Voltage Networks

    DEFF Research Database (Denmark)

    Diaz de Cerio Mendaza, Iker; Szczesny, Ireneusz Grzegorz; Pillai, Jayakrishnan Radhakrishna

    2015-01-01

    Moving towards a carbon free energy system has become an objective for many countries nowadays. Among other changes, the electrification of strategic sectors such as heating and transportation is inevitable. As a consequence, the current power system load will substantially increase...... for controlling the demand response of a low voltage grid. This is designed to; i) maximize the grid utilization, thereby reducing the need for reinforcement, ii) accommodate the maximum number of flexible loads and iii) satisfy the power and comfort requirements from each of the consumers in the network....... In this context, the nature of the expected loads (heat pumps, plug-in electric vehicles, etc.) makes the low voltage networks specially targeted. A promising solution to overcome the challenges resulting from their grid integration, is demand response. This paper introduces a hierarchical structure...

  2. Water demand prediction using artificial neural networks and support vector regression

    CSIR Research Space (South Africa)

    Msiza, IS

    2008-11-01

    Full Text Available Neural Networks and Support Vector Regression Ishmael S. Msiza1, Fulufhelo V. Nelwamondo1,2, Tshilidzi Marwala3 . 1Modelling and Digital Science, CSIR, Johannesburg,SOUTH AFRICA 2Graduate School of Arts and Sciences, Harvard University, Cambridge..., Massachusetts, USA 3School of Electrical and Information Engineering, University of the Witwatersrand, Johannesburg, SOUTH AFRICA Email: imsiza@csir.co.za, nelwamon@fas.harvard.edu, tshilidzi.marwala@wits.ac.za Abstract— Computational Intelligence techniques...

  3. Integrated Project Control and Technical Support

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Yeon; Joo, Po Kook; Kim, Gye Ryung (and others)

    2003-06-15

    First, Since PEFP puts it's aim on technology innovation through collaboration and technological fusion among the subprojects from the various fields, It has been tried to make the subprojects consist with the goal of the whole project through building and running the integrated project control system. Also, adopting CPM(Critical Process Management), intensive process management framework has been founded. Secondly, for the every procedure, including purchase, building, installation and a trial running, license, quality control, etc., could be efficiently executed, every related task has been carried out. And, the tasks involved in international cooperative relationship and host site selection are carried out as well, so that PEFP could be firmly supported. Finally, TRM(Technology Road Map) is made up not only for the purpose of managing efficiency and effectiveness on the investment, but also for the purpose of life cycle management from developing stage to commercializing stage.

  4. Supporting Cross-Organizational Process Control

    Science.gov (United States)

    Angelov, Samuil; Vonk, Jochem; Vidyasankar, Krishnamurthy; Grefen, Paul

    E-contracts express the rights and obligations of parties through a formal, digital representation of the contract provisions. In process intensive relationships, e-contracts contain business processes that a party promises to perform for the counter party, optionally allowing monitoring of the execution of the promised processes. In this paper, we describe an approach in which the counter party is allowed to control the process execution. This approach will lead to more flexible and efficient business relations which are essential in the context of modern, highly dynamic and complex collaborations among companies. We present a specification of the process controls available to the consumer and their support in the private process specification of the provider.

  5. Optimal strategy analysis based on robust predictive control for inventory system with random demand

    Science.gov (United States)

    Saputra, Aditya; Widowati, Sutrisno

    2017-12-01

    In this paper, the optimal strategy for a single product single supplier inventory system with random demand is analyzed by using robust predictive control with additive random parameter. We formulate the dynamical system of this system as a linear state space with additive random parameter. To determine and analyze the optimal strategy for the given inventory system, we use robust predictive control approach which gives the optimal strategy i.e. the optimal product volume that should be purchased from the supplier for each time period so that the expected cost is minimal. A numerical simulation is performed with some generated random inventory data. We simulate in MATLAB software where the inventory level must be controlled as close as possible to a set point decided by us. From the results, robust predictive control model provides the optimal strategy i.e. the optimal product volume that should be purchased and the inventory level was followed the given set point.

  6. Day-Ahead Scheduling Considering Demand Response as a Frequency Control Resource

    Directory of Open Access Journals (Sweden)

    Yu-Qing Bao

    2017-01-01

    Full Text Available The development of advanced metering technologies makes demand response (DR able to provide fast response services, e.g., primary frequency control. It is recognized that DR can contribute to the primary frequency control like thermal generators. This paper proposes a day-ahead scheduling method that considers DR as a frequency control resource, so that the DR resources can be dispatched properly with other resources. In the proposed method, the objective of frequency control is realized by defining a frequency limit equation under a supposed contingency. The frequency response model is used to model the dynamics of system frequency. The nonlinear frequency limit equation is transformed to a linear arithmetic equation by piecewise linearization, so that the problem can be solved by mixed integer linear programming (MILP. Finally, the proposed method is verified on numerical examples.

  7. Effects of Granular Control on Customers’ Perspective and Behavior with Automated Demand Response Systems

    Energy Technology Data Exchange (ETDEWEB)

    Schetrit, Oren; Kim, Joyce; Yin, Rongxin; Kiliccote, Sila

    2014-08-01

    Automated demand response (Auto-DR) is expected to close the loop between buildings and the grid by providing machine-to-machine communications to curtail loads without the need for human intervention. Hence, it can offer more reliable and repeatable demand response results to the grid than the manual approach and make demand response participation a hassle-free experience for customers. However, many building operators misunderstand Auto-DR and are afraid of losing control over their building operation. To ease the transition from manual to Auto-DR, we designed and implemented granular control of Auto-DR systems so that building operators could modify or opt out of individual load-shed strategies whenever they wanted. This paper reports the research findings from this effort demonstrated through a field study in large commercial buildings located in New York City. We focused on (1) understanding how providing granular control affects building operators’ perspective on Auto-DR, and (2) evaluating the usefulness of granular control by examining their interaction with the Auto-DR user interface during test events. Through trend log analysis, interviews, and surveys, we found that: (1) the opt-out capability during Auto-DR events can remove the feeling of being forced into load curtailments and increase their willingness to adopt Auto-DR; (2) being able to modify individual load-shed strategies allows flexible Auto-DR participation that meets the building’s changing operational requirements; (3) a clear display of automation strategies helps building operators easily identify how Auto-DR is functioning and can build trust in Auto-DR systems.

  8. Review of foreign equipment for powered support control

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, W; Sobczyk, J

    1986-10-01

    A new generation of control systems are comparatively evaluated developed by Dowty, Hemscheidt and Thyssen-Siemens for powered supports and shield supports. Types of functions controlled by each system are discussed: support advancing (lowering support canopy, advancing, increasing pressure), control of support position, advancing chain conveyor. The following control systems are described: fully automatic control, remote control from a gate road, manual control from an adjacent support unit. Types of electronic equipment used in the control systems are described: microcomputers (8-bit CMOS device), 8-bit microcomputers, transmission systems, measuring instruments. Advantages of control systems developed and manufactured by the 3 companies are comparatively evaluated.

  9. The moderating effect of control over work scheduling and overtime on the relationship between workload demands and perceived job risk.

    Science.gov (United States)

    Näswall, Katharina; Burt, Christopher D B; Pearce, Megan

    2015-01-01

    This study investigated the impact of workload demands on perceived job risk using the Job Demand-Control model as a research framework. The primary objective was to test the hypothesis that employee control over work scheduling and overtime would moderate the relationship between workload demands and perceived job risk. Ninety-six participants working in a variety of industries completed measures of workload demands, and of control over work scheduling and overtime, and a measure of perceived job risk. Workload demands predicted higher perceptions of job risk. However, the results also suggest that control over overtime moderated this relationship, where those with the combination of high workload demands and low control over overtime reported higher levels of perceived risk. The results indicate that the JDC model is applicable to safety research. The results suggest that employee control over workload demands is an important variable to consider in terms of managing workplace safety. The present study also points to important areas for future research to explore in order to further understand the connection between demands and safety.

  10. A demanding web-based PACS supported by web services technology

    Science.gov (United States)

    Costa, Carlos M. A.; Silva, Augusto; Oliveira, José L.; Ribeiro, Vasco G.; Ribeiro, José

    2006-03-01

    During the last years, the ubiquity of web interfaces have pushed practically all PACS suppliers to develop client applications in which clinical practitioners can receive and analyze medical images, using conventional personal computers and Web browsers. However, due to security and performance issues, the utilization of these software packages has been restricted to Intranets. Paradigmatically, one of the most important advantages of digital image systems is to simplify the widespread sharing and remote access of medical data between healthcare institutions. This paper analyses the traditional PACS drawbacks that contribute to their reduced usage in the Internet and describes a PACS based on Web Services technology that supports a customized DICOM encoding syntax and a specific compression scheme providing all historical patient data in a unique Web interface.

  11. Assessing the potential for using wetlands as intermediary storages to conjunctively maintain ecological values and support agricultural demands.

    Science.gov (United States)

    Ning, Nathan S P; Watkins, Susanne C; Gawne, Ben; Nielsen, Daryl L

    2012-09-30

    Water sharing to meet both agricultural and environmental demands is a critical issue affecting the health of many floodplain river systems around the world. This study explored the potential for using wetlands as temporary off-river storages to conjunctively maintain ecological values and support agricultural demands by assessing the effects of artificial drawdown on wetland aquatic plant communities. An initial experiment was undertaken in outdoor mesocosms in which four different treatments were compared over a 131 day duration: (1) natural drawdown where the water was left to drawdown naturally via evaporation; (2) partial drawdown where approximately half of the volume of water was pumped out after 42 days; (3) stepped drawdown where approximately half of the volume of water pumped out after 42 days, and then the remaining volume of water was pumped out after 117 days; and (4) total drawdown where all of the of water was pumped out after 117 days. A complementary field study was subsequently undertaken where two wetlands were left to drawdown naturally and two were partially drawn down artificially (i.e. had approximately half of their volume removed by pumping). Results from both of these studies indicated that neither aquatic plant abundance nor taxon richness were adversely affected by partial drawdown. Rather, both studies showed that aquatic plant communities subjected to a partial drawdown treatment became more species rich and diverse than communities subjected to a natural drawdown treatment. This suggests that it may be possible to use wetlands as intermediary storages for the dual purposes of maintaining ecological values and supporting agricultural demands. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  12. Experimental analysis of fuzzy controlled energy efficient demand controlled ventilation economizer cycle variable air volume air conditioning system

    Directory of Open Access Journals (Sweden)

    Rajagopalan Parameshwaran

    2008-01-01

    Full Text Available In the quest for energy conservative building design, there is now a great opportunity for a flexible and sophisticated air conditioning system capable of addressing better thermal comfort, indoor air quality, and energy efficiency, that are strongly desired. The variable refrigerant volume air conditioning system provides considerable energy savings, cost effectiveness and reduced space requirements. Applications of intelligent control like fuzzy logic controller, especially adapted to variable air volume air conditioning systems, have drawn more interest in recent years than classical control systems. An experimental analysis was performed to investigate the inherent operational characteristics of the combined variable refrigerant volume and variable air volume air conditioning systems under fixed ventilation, demand controlled ventilation, and combined demand controlled ventilation and economizer cycle techniques for two seasonal conditions. The test results of the variable refrigerant volume and variable air volume air conditioning system for each techniques are presented. The test results infer that the system controlled by fuzzy logic methodology and operated under the CO2 based mechanical ventilation scheme, effectively yields 37% and 56% per day of average energy-saving in summer and winter conditions, respectively. Based on the experimental results, the fuzzy based combined system can be considered to be an alternative energy efficient air conditioning scheme, having significant energy-saving potential compared to the conventional constant air volume air conditioning system.

  13. Effective production control in an automotive industry: MRP vs. demand-driven MRP

    Science.gov (United States)

    Shofa, Mohamad Jihan; Widyarto, Wahyu Oktri

    2017-06-01

    Material Requirements Planning (MRP) has deficiencies when dealing with current business environments, marked by a more complex network, a huge variety of products with longer lead time, and uncertain demands. This drives Demand-Driven MRP (DDMRP) approach to deal with those challenges. DDMRP is designed to connect the availability of materials and supplies directly from the actual condition using bills of materials (BOMs). Nevertheless, only few studies have scientifically proved the performance of DDMRP over MRP for controlling production and inventory control. Therefore, this research fills this gap by evaluating and comparing the performance of DDMRP and MRP in terms of level of effective inventory in the system. The evaluation was conducted through a simulation using data from an automotive company in Indonesia. The input parameters of scenarios were given for running the simulation. Based on the simulation, for the observed critical parts, DDMRP gave better results than MRP in terms of lead time and inventory level. DDMRP compressed the lead time part from 52 to 3 days (94% reduced) and, overall, the inventory level was in an effective condition. This suggests that DDMRP is more effective for controlling the production-inventory than MRP.

  14. Multi-Time Scale Control of Demand Flexibility in Smart Distribution Networks

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu P.; Myers, Kurt S.; Bak-Jensen, Birgitte

    2017-01-01

    , and distribution system operator’s perspectives. A hierarchical control architecture (HCA) comprising scheduling, coordinative, and adaptive layers is then designed to realize their coordinative goal. This is realized by integrating multi-time scale controls that work from a day-ahead scheduling up to real-time...... adaptive control. The performance of the developed method is investigated with high EV penetration in a typical residential distribution grid. The simulation results demonstrate that HCA efficiently utilizes demand flexibility stemming from EVs to solve grid unbalancing and congestions with simultaneous...... maximization of economic benefits to the participating actors. This is ensured by enabling EV participation in day-ahead, balancing, and regulation markets. For the given network configuration and pricing structure, HCA ensures the EV owners to get paid up to five times the cost they were paying without...

  15. An inventory control project in a major Danish company using compound renewal demand models

    DEFF Research Database (Denmark)

    Larsen, Christian; Seiding, Claus Hoe; Teller, Christian

    operation is highly automated. However, the procedures for estimating demands and the policies for the inventory control system that were in use at the beginning of the project did not fully match the sophisticated technological standard of the physical system. During the initial phase of the project...... We describe the development of a framework to compute the optimal inventory policy for a large spare-parts' distribution centre operation in the RA division of the Danfoss Group in Denmark. The RA division distributes spare parts worldwide for cooling and A/C systems. The warehouse logistics...

  16. The effects of moderate fatigue on dynamic balance control and attentional demands

    Directory of Open Access Journals (Sweden)

    Teasdale Normand

    2006-09-01

    Full Text Available Abstract Background During daily activities, the active control of balance often is a task per se (for example, when standing in a moving bus. Other constraints like fatigue can add to the complexity of this balance task. In the present experiment, we examined how moderate fatigue induced by fast walking on a treadmill challenged dynamic balance control. We also examined if the attentional demands for performing the balance task varied with fatigue. Methods Subjects (n = 10 performed simultaneously a dynamic balance control task and a probe reaction time task (RT (serving as an indicator of attentional demands before and after three periods of moderate fatigue (fast walking on a treadmill. For the balance control task, the real-time displacement of the centre of pressure (CP was provided on a monitor placed in front of the subject, at eye level. Subjects were asked to keep their CP within a target (moving box moving upward and downward on the monitor. The tracking performance was measured (time spent outside the moving box and the CP behavior analyzed (mean CP speed and mean frequency of the CP velocity. Results Moderate fatigue led to an immediate decrement of the performance on the balance control task; increase of the percentage of time spent outside the box and increase of the mean CP speed. Across the three fatigue periods, subjects improved their tracking performance and reduced their mean CP speed. This was achieved by increasing their frequency of actions; mean frequency of the CP velocity were higher for the fatigue periods than for the no fatigue periods. Fatigue also induced an increase in the attentional demands suggesting that more cognitive resources had to be allocated to the balance task with than without fatigue. Conclusion Fatigue induced by fast walking had an initial negative impact on the control of balance. Nonetheless, subjects were able to compensate the effect of the moderate fatigue by increasing the frequency of

  17. Modeling and Forecast Biological Oxygen Demand (BOD using Combination Support Vector Machine with Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Abazar Solgi

    2017-06-01

    Full Text Available Introduction: Chemical pollution of surface water is one of the serious issues that threaten the quality of water. This would be more important when the surface waters used for human drinking supply. One of the key parameters used to measure water pollution is BOD. Because many variables affect the water quality parameters and a complex nonlinear relationship between them is established conventional methods can not solve the problem of quality management of water resources. For years, the Artificial Intelligence methods were used for prediction of nonlinear time series and a good performance of them has been reported. Recently, the wavelet transform that is a signal processing method, has shown good performance in hydrological modeling and is widely used. Extensive research has been globally provided in use of Artificial Neural Network and Adaptive Neural Fuzzy Inference System models to forecast the BOD. But support vector machine has not yet been extensively studied. For this purpose, in this study the ability of support vector machine to predict the monthly BOD parameter based on the available data, temperature, river flow, DO and BOD was evaluated. Materials and Methods: SVM was introduced in 1992 by Vapnik that was a Russian mathematician. This method has been built based on the statistical learning theory. In recent years the use of SVM, is highly taken into consideration. SVM was used in applications such as handwriting recognition, face recognition and has good results. Linear SVM is simplest type of SVM, consists of a hyperplane that dataset of positive and negative is separated with maximum distance. The suitable separator has maximum distance from every one of two dataset. So about this machine that its output groups label (here -1 to +1, the aim is to obtain the maximum distance between categories. This is interpreted to have a maximum margin. Wavelet transform is one of methods in the mathematical science that its main idea was

  18. Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Programs - calibration Report for Phoenix Testbed : Final Report. [supporting datasets - Phoenix Testbed

    Science.gov (United States)

    2017-07-26

    The datasets in this zip file are in support of FHWA-JPO-16-379, Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Program...

  19. Opportunities for Automated Demand Response in Wastewater Treatment Facilities in California - Southeast Water Pollution Control Plant Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Daniel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goli, Sasank [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McKane, Aimee [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-12-20

    This report details a study into the demand response potential of a large wastewater treatment facility in San Francisco. Previous research had identified wastewater treatment facilities as good candidates for demand response and automated demand response, and this study was conducted to investigate facility attributes that are conducive to demand response or which hinder its implementation. One years' worth of operational data were collected from the facility's control system, submetered process equipment, utility electricity demand records, and governmental weather stations. These data were analyzed to determine factors which affected facility power demand and demand response capabilities The average baseline demand at the Southeast facility was approximately 4 MW. During the rainy season (October-March) the facility treated 40% more wastewater than the dry season, but demand only increased by 4%. Submetering of the facility's lift pumps and centrifuges predicted load shifts capabilities of 154 kW and 86 kW, respectively, with large lift pump shifts in the rainy season. Analysis of demand data during maintenance events confirmed the magnitude of these possible load shifts, and indicated other areas of the facility with demand response potential. Load sheds were seen to be possible by shutting down a portion of the facility's aeration trains (average shed of 132 kW). Load shifts were seen to be possible by shifting operation of centrifuges, the gravity belt thickener, lift pumps, and external pump stations These load shifts were made possible by the storage capabilities of the facility and of the city's sewer system. Large load reductions (an average of 2,065 kW) were seen from operating the cogeneration unit, but normal practice is continuous operation, precluding its use for demand response. The study also identified potential demand response opportunities that warrant further study: modulating variable-demand aeration loads, shifting

  20. How do Air Traffic Controllers Use Automation and Tools Differently During High Demand Situations?

    Science.gov (United States)

    Kraut, Joshua M.; Mercer, Joey; Morey, Susan; Homola, Jeffrey; Gomez, Ashley; Prevot, Thomas

    2013-01-01

    In a human-in-the-loop simulation, two air traffic controllers managed identical airspace while burdened with higher than average workload, and while using advanced tools and automation designed to assist with scheduling aircraft on multiple arrival flows to a single meter fix. This paper compares the strategies employed by each controller, and investigates how the controllers' strategies change while managing their airspace under more normal workload conditions and a higher workload condition. Each controller engaged in different methods of maneuvering aircraft to arrive on schedule, and adapted their strategies to cope with the increased workload in different ways. Based on the conclusions three suggestions are made: that quickly providing air traffic controllers with recommendations and information to assist with maneuvering and scheduling aircraft when burdened with increased workload will improve the air traffic controller's effectiveness, that the tools should adapt to the strategy currently employed by a controller, and that training should emphasize which traffic management strategies are most effective given specific airspace demands.

  1. Intelligent systems supporting the control room operators

    International Nuclear Information System (INIS)

    Berger, E.

    1997-01-01

    The operational experience obtained with the various applications of the systems discussed in this paper shows that more consequent use of the systems will make detection and management of disturbances still more efficient and faster. This holds true both for a low level of process automation and for power plants with a high level of automation. As for conventional power plants, the trend clearly is towards higher degrees of automation and consequent application of supporting systems. Thus, higher availability and rapid failure management are achieved, at low effects on normal operation. These systems are monitoring and process control systems, expert systems, and systems for optimal use of the equipment, or systems for post-incident analyses and computer-assisted on-shift protocols, or operating manuals. (orig./CB) [de

  2. Time Course of Brain Network Reconfiguration Supporting Inhibitory Control.

    Science.gov (United States)

    Popov, Tzvetan; Westner, Britta U; Silton, Rebecca L; Sass, Sarah M; Spielberg, Jeffrey M; Rockstroh, Brigitte; Heller, Wendy; Miller, Gregory A

    2018-05-02

    Hemodynamic research has recently clarified key nodes and links in brain networks implementing inhibitory control. Although fMRI methods are optimized for identifying the structure of brain networks, the relatively slow temporal course of fMRI limits the ability to characterize network operation. The latter is crucial for developing a mechanistic understanding of how brain networks shift dynamically to support inhibitory control. To address this critical gap, we applied spectrally resolved Granger causality (GC) and random forest machine learning tools to human EEG data in two large samples of adults (test sample n = 96, replication sample n = 237, total N = 333, both sexes) who performed a color-word Stroop task. Time-frequency analysis confirmed that recruitment of inhibitory control accompanied by slower behavioral responses was related to changes in theta and alpha/beta power. GC analyses revealed directionally asymmetric exchanges within frontal and between frontal and parietal brain areas: top-down influence of superior frontal gyrus (SFG) over both dorsal ACC (dACC) and inferior frontal gyrus (IFG), dACC control over middle frontal gyrus (MFG), and frontal-parietal exchanges (IFG, precuneus, MFG). Predictive analytics confirmed a combination of behavioral and brain-derived variables as the best set of predictors of inhibitory control demands, with SFG theta bearing higher classification importance than dACC theta and posterior beta tracking the onset of behavioral response. The present results provide mechanistic insight into the biological implementation of a psychological phenomenon: inhibitory control is implemented by dynamic routing processes during which the target response is upregulated via theta-mediated effective connectivity within key PFC nodes and via beta-mediated motor preparation. SIGNIFICANCE STATEMENT Hemodynamic neuroimaging research has recently clarified regional structures in brain networks supporting inhibitory control. However, due to

  3. Biomass Assessment. Assessment of global biomass potentials and their links to food, water, biodiversity, energy demand and economy. Inventory and analysis of existing studies. Supporting document

    International Nuclear Information System (INIS)

    Dornburg, V.; Faaij, A.; Verweij, P.; Banse, M.; Van Diepen, K.; Van Keulen, H.; Langeveld, H.; Meeusen, M.; Van de Ven, G.; Wester, F.; Alkemade, R.; Ten Brink, B.; Van den Born, G.J.; Van Oorschot, M.; Ros, J.; Smout, F.; Van Vuuren, D.; Van den Wijngaart, R.; Aiking, H.; Londo, M.; Mozaffarian, H.; Smekens, K.; Lysen, E.

    2008-01-01

    This supporting document contains the result from the inventory phase of the biomass assessment of global biomass potentials and their links to food, water, biodiversity, energy demand and economy. This study provides a comprehensive assessment of global biomass potential estimates, focusing on the various factors affecting these potentials, such as food supplies, water use, biodiversity, energy demands and agro-economics

  4. Emotional job resources and emotional support seeking as moderators of the relation between emotional job demands and emotional exhaustion : A two-wave panel study

    NARCIS (Netherlands)

    Van de Ven, B.; van den Tooren, M.; Vlerick, P.

    2013-01-01

    In the present study, the relation between emotional job demands and emotional exhaustion was investigated, as was the moderating role of emotional job resources and emotional support seeking on this relation. We hypothesized a positive lagged effect of emotional job demands on emotional exhaustion,

  5. Work ability in nursing: relationship with psychological demands and control over the work.

    Science.gov (United States)

    Prochnow, Andrea; Magnago, Tânia Solange Bosi de Souza; Urbanetto, Janete de Souza; Beck, Carmem Lúcia Colomé; Lima, Suzinara Beatriz Soares de; Greco, Patrícia Bitencourt Toscani

    2013-01-01

    to evaluate the association between psychological demands, control over the work and the reduction of work ability of nursing professionals. this cross-sectional study involved 498 nursing professionals of a university hospital in the State of Rio Grande do Sul, Brazil. Data collection was carried out in 2009 using the Brazilian versions of the Work Ability Index and Job Stress Scale, with logistic regression models used for the data analysis. the prevalence of 43.3% for reduced work ability and 29.7% for high-strain in the job (high psychological demand and low control) were observed. The chances for professionals presenting reduced work ability under high-strain were higher and significant when compared to those classified as being under low-strain, even after adjusting for potential confounders, except for age and gender. a high prevalence of reduced work ability was observed. This evidence indicates the need for investigation and detailed analysis of the psychosocial aspects of the professionals with regard to the health/disease process of nursing professionals.

  6. Demand Response Advanced Controls Framework and Assessment of Enabling Technology Costs

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Jennifer; Cappers, Peter

    2017-08-28

    The Demand Response Advanced Controls Framework and Assessment of Enabling Technology Costs research describe a variety of DR opportunities and the various bulk power system services they can provide. The bulk power system services are mapped to a generalized taxonomy of DR “service types”, which allows us to discuss DR opportunities and bulk power system services in fewer yet broader categories that share similar technological requirements which mainly drive DR enablement costs. The research presents a framework for the costs to automate DR and provides descriptions of the various elements that drive enablement costs. The report introduces the various DR enabling technologies and end-uses, identifies the various services that each can provide to the grid and provides the cost assessment for each enabling technology. In addition to a report, this research includes a Demand Response Advanced Controls Database and User Manual. They are intended to provide users with the data that underlies this research and instructions for how to use that database more effectively and efficiently.

  7. Integrated Project Control and Technical Support

    International Nuclear Information System (INIS)

    Kim, Jun Yeon; Kim, Jun Yeon; Joo, Po Kook and others

    2005-08-01

    First, Since PEFP puts it's aim on technology innovation through collaboration and technological fusion among the sub-projects from the various fields. It has been tried to make the sub-projects consist with the goal of the whole project through building and running the integrated project control system. Also, adopting CPM(Critical Process Management), intensive process management framework has been founded. Secondly, for the every procedure, including purchase, building, installation and a trial running, license, quality control, etc., could be efficiently executed, every related task has been carried out. And, the tasks involved in international cooperative relationship and host site selection are carried out as well, so that PEFP could be firmly supported. Finally, Strategic management procedures including TRM(Technology Road Map), economic evaluation on PEFP, preliminary evaluation on company-involved R and D and TRESIS(Technology, Resources, Economic Evaluation System) are made up not only for the purpose of managing efficiency and effectiveness on the investment, but also for the purpose of life cycle management from developing stage to commercializing stage

  8. Integrated Project Control and Technical Support

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Yeon; Kim, Jun Yeon; Joo, Po Kook and others

    2005-08-15

    First, Since PEFP puts it's aim on technology innovation through collaboration and technological fusion among the sub-projects from the various fields. It has been tried to make the sub-projects consist with the goal of the whole project through building and running the integrated project control system. Also, adopting CPM(Critical Process Management), intensive process management framework has been founded. Secondly, for the every procedure, including purchase, building, installation and a trial running, license, quality control, etc., could be efficiently executed, every related task has been carried out. And, the tasks involved in international cooperative relationship and host site selection are carried out as well, so that PEFP could be firmly supported. Finally, Strategic management procedures including TRM(Technology Road Map), economic evaluation on PEFP, preliminary evaluation on company-involved R and D and TRESIS(Technology, Resources, Economic Evaluation System) are made up not only for the purpose of managing efficiency and effectiveness on the investment, but also for the purpose of life cycle management from developing stage to commercializing stage.

  9. Supply and Demand Control of Distributed Generators in a Microgrid for New Energy

    Science.gov (United States)

    Shimakage, Toyonari; Sumita, Jiro; Uchiyama, Noriyuki; Kato, Takeyoshi; Suzuoki, Yasuo

    We report the operational results of distributed generators (DGs) in a microgrid and present the effects after incorporating photovoltaic power generation (PV) systems into the microgrid for electric power system. The microgrid was constructed at the EXPO 2005 Aichi site as part of a demonstration promoted by NEDO. A solution is needed to problems where instability in the DGs that utilize natural energy such as solar light and wind force negatively influence existing electric power systems. So, we developed energy control system and controlled DGs output to reduce the fluctuation at the grid connected point caused by PV system's instability output. Our microgrid consists of DGs such as PV systems, fuel cells, and NaS batteries, and these DGs are controlled by an energy control system. We verified practical effectiveness of the installing the microgrid as follows. (1) 99.5% of the power imbalance in the supply and demand over 30 minutes was within a range of ±3% under normal operating conditions, (2) the microgrid contributes to the load leveling, (3) energy control system smoothes the power flow fluctuation of PV system output at the grid connected point, (4) in the future, installing a microgrid will help reduce the additional LFC (Load Frequency Control) capacity.

  10. Demand Controlled Economizer Cycles: A Direct Digital Control Scheme for Heating, Ventilating, and Air Conditioning Systems,

    Science.gov (United States)

    1984-05-01

    Control Ignored any error of 1/10th degree or less. This was done by setting the error term E and the integral sum PREINT to zero If then absolute value of...signs of two errors jeq tdiff if equal, jump clr @preint else zero integal sum tdiff mov @diff,rl fetch absolute value of OAT-RAT ci rl,25 is...includes a heating coil and thermostatic control to maintain the air in this path at an elevated temperature, typically around 80 degrees Farenheit (80 F

  11. Force Structure. DOD Needs to Integrate Data into Its Force Identification Process and Examine Options to Meet Requirements for High-Demand Support Forces

    National Research Council Canada - National Science Library

    2006-01-01

    ...) will continue to meet its requirements using an all-volunteer force. The Army, in particular, has faced continuing demand for large numbers of forces, especially for forces with support skills...

  12. A Closed-Loop Control Strategy for Air Conditioning Loads to Participate in Demand Response

    Directory of Open Access Journals (Sweden)

    Xiaoqing Hu

    2015-08-01

    Full Text Available Thermostatically controlled loads (TCLs, such as air conditioners (ACs, are important demand response resources—they have a certain heat storage capacity. A change in the operating status of an air conditioner in a small range will not noticeably affect the users’ comfort level. Load control of TCLs is considered to be equivalent to a power plant of the same capacity in effect, and it can significantly reduce the system pressure to peak load shift. The thermodynamic model of air conditioning can be used to study the aggregate power of a number of ACs that respond to the step signal of a temperature set point. This paper analyzes the influence of the parameters of each AC in the group to the indoor temperature and the total load, and derives a simplified control model based on the two order linear time invariant transfer function. Then, the stability of the model and designs its Proportional-Integral-Differential (PID controller based on the particle swarm optimization (PSO algorithm is also studied. The case study presented in this paper simulates both scenarios of constant ambient temperature and changing ambient temperature to verify the proposed transfer function model and control strategy can closely track the reference peak load shifting curves. The study also demonstrates minimal changes in the indoor temperature and the users’ comfort level.

  13. Dynamic postural control and associated attentional demands in contemporary dancers versus non-dancers.

    Science.gov (United States)

    Sirois-Leclerc, Geneviève; Remaud, Anthony; Bilodeau, Martin

    2017-01-01

    Postural control is not a fully automatic process, but requires a certain level of attention, particularly as the difficulty of the postural task increases. This study aimed at testing whether experienced contemporary dancers, because of their specialized training involving the control of posture/balance, would present with a dual-task performance suggesting lesser attentional demands associated with dynamic postural control compared with non-dancers. Twenty dancers and 16 non-dancers performed a dynamic postural tracking task in both antero-posterior and side-to-side directions, while standing on a force platform. The postural task was performed, in turn, 1) as a stand-alone task, and concurrently with both 2) a simple reaction time task and 3) a choice reaction time task. Postural control performance was estimated through variables calculated from centre of pressure movements. Although no overall group difference was found in reaction time values, we found a better ability to control the side to side movements of the centre of pressure during the tracking task in dancers compared with non-dancers, which was dependent on the secondary task. This suggests that such increased ability is influenced by available attentional resources.

  14. Dynamic postural control and associated attentional demands in contemporary dancers versus non-dancers.

    Directory of Open Access Journals (Sweden)

    Geneviève Sirois-Leclerc

    Full Text Available Postural control is not a fully automatic process, but requires a certain level of attention, particularly as the difficulty of the postural task increases. This study aimed at testing whether experienced contemporary dancers, because of their specialized training involving the control of posture/balance, would present with a dual-task performance suggesting lesser attentional demands associated with dynamic postural control compared with non-dancers. Twenty dancers and 16 non-dancers performed a dynamic postural tracking task in both antero-posterior and side-to-side directions, while standing on a force platform. The postural task was performed, in turn, 1 as a stand-alone task, and concurrently with both 2 a simple reaction time task and 3 a choice reaction time task. Postural control performance was estimated through variables calculated from centre of pressure movements. Although no overall group difference was found in reaction time values, we found a better ability to control the side to side movements of the centre of pressure during the tracking task in dancers compared with non-dancers, which was dependent on the secondary task. This suggests that such increased ability is influenced by available attentional resources.

  15. The extent to which ATP demand controls the glycolytic flux depends strongly on the organism and conditions for growth

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Westerhoff, H.V.; Snoep, J.L.

    2002-01-01

    Using molecular genetics we have introduced uncoupled ATPase activity in two different bacterial species, Escherichia coli and Lactococcus lactis, and determined the elasticities of the growth rate and glycolytic flux towards the intracellular [ATP]/[ADP] ratio. During balanced growth in batch...... cultures of E. coli the ATP demand was found to have almost full control on the glycolytic flux (FCC=0.96) and the flux could be stimulated by 70%. In contrast to this, in L. lactis the control by ATP demand on the glycolytic flux was close to zero. However, when we used non-growing cells of L. lactis...... (which have a low glycolytic flux) the ATP demand had a high flux control and the flux could be stimulated more than two fold. We suggest that the extent to which ATP demand controls the glycolytic flux depends on how much excess capacity of glycolysis is present in the cells....

  16. Renewable generation and demand response integration in micro-grids. Development of a new energy management and control system

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Bel, C.; Escriva-Escriva, G.; Alcazar-Ortega, M. [Institute for Energy Engineering, Universitat Politecnica de Valencia, Valencia (Spain)

    2013-11-15

    The aim of this research resides in the development of an energy management and control system to control a micro-grid based on the use of renewable generation and demand resources to introduce the application of demand response concepts to the management of micro-grids in order to effectively integrate the demand side as an operation resource for the grid and improve energy efficiency of the elements. As an additional result, the evaluation of reductions in the total amount of CO2 emitted into the atmosphere due to the improvement of the energy efficiency of the system is assessed.

  17. Fast-responsive hydrogel as an injectable pump for rapid on-demand fluidic flow control.

    Science.gov (United States)

    Luo, Rongcong; Dinh, Ngoc-Duy; Chen, Chia-Hung

    2017-05-01

    Chemically synthesized functional hydrogels have been recognized as optimized soft pumps for on-demand fluidic regulation in micro-systems. However, the challenges regarding the slow responses of hydrogels have very much limited their application in effective fluidic flow control. In this study, a heterobifunctional crosslinker (4-hydroxybutyl acrylate)-enabled two-step hydrothermal phase separation process for preparing a highly porous hydrogel with fast response dynamics was investigated for the fabrication of novel microfluidic functional units, such as injectable valves and pumps. The cylinder-shaped hydrogel, with a diameter of 9 cm and a height of 2.5 cm at 25 °C, achieved a size reduction of approximately 70% in less than 30 s after the hydrogels were heated at 40 °C. By incorporating polypyrrole nanoparticles as photothermal transducers, a photo-responsive composite hydrogel was approached and exhibited a remotely triggerable fluidic regulation and pumping ability to generate significant flows, showing on-demand water-in-oil droplet generation by laser switching, whereby the droplet size could be tuned by adjusting the laser intensity and irradiation period with programmable manipulation.

  18. Control system upgrades support better plant economics

    International Nuclear Information System (INIS)

    De Grosbois, J.; Hepburn, A.; Storey, H.; Basso, R.; Kumar, V.

    2002-01-01

    This paper (second in the series, see [1]) provides insight on how nuclear plants can achieve better efficiencies and reduced operations and maintenance (O and M) costs through focused control system upgrades. An understanding of this relationship is necessary to properly assess the economics of plant refurbishment decisions. Traditional economic feasibility assessment methods such as benefit cost analysis (BCA), internal rate of return (IRR), benefit cost ratios (B/C), or payback analysis are often performed without full consideration of project alternatives, quantified benefits, and life cycle costing. Consideration must be given to not only capital cost and project risk, but also to the potential economic benefits of new technology and added functionality offered by plant upgrades. Recent experience shows that if upgrades are focused on priority objectives, and are effectively implemented, they can deliver significant payback over the life of the plant, sometimes orders of magnitude higher than their initial capital cost. The following discussion explores some of the key issues and rationale behind upgrade decisions and their impact on improved plant efficiency and reduced O and M costs. A subsequent paper will explain how the justification for these improvements can be captured in an economic analysis and feasibility study to support strategic decision-making in a plant refurbishment context. (author)

  19. STTR Phase I: Low-Cost, High-Accuracy, Whole-Building Carbon Dioxide Monitoring for Demand Control Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Hallstrom, Jason; Ni, Zheng Richard

    2018-05-15

    This STTR Phase I project assessed the feasibility of a new CO2 sensing system optimized for low-cost, high-accuracy, whole-building monitoring for use in demand control ventilation. The focus was on the development of a wireless networking platform and associated firmware to provide signal conditioning and conversion, fault- and disruptiontolerant networking, and multi-hop routing at building scales to avoid wiring costs. Early exploration of a bridge (or “gateway”) to direct digital control services was also explored. Results of the project contributed to an improved understanding of a new electrochemical sensor for monitoring indoor CO2 concentrations, as well as the electronics and networking infrastructure required to deploy those sensors at building scales. New knowledge was acquired concerning the sensor’s accuracy, environmental response, and failure modes, and the acquisition electronics required to achieve accuracy over a wide range of CO2 concentrations. The project demonstrated that the new sensor offers repeatable correspondence with commercial optical sensors, with supporting electronics that offer gain accuracy within 0.5%, and acquisition accuracy within 1.5% across three orders of magnitude variation in generated current. Considering production, installation, and maintenance costs, the technology presents a foundation for achieving whole-building CO2 sensing at a price point below $0.066 / sq-ft – meeting economic feasibility criteria established by the Department of Energy. The technology developed under this award addresses obstacles on the critical path to enabling whole-building CO2 sensing and demand control ventilation in commercial retrofits, small commercial buildings, residential complexes, and other highpotential structures that have been slow to adopt these technologies. It presents an opportunity to significantly reduce energy use throughout the United States a

  20. Snack purchasing is healthier when the cognitive demands of choice are reduced: A randomized controlled trial.

    Science.gov (United States)

    Allan, Julia L; Johnston, Marie; Campbell, Neil

    2015-07-01

    Individuals with inefficient executive (higher level cognitive) function have a reduced ability to resist dietary temptation. The present study aimed to design and test a theory-based point-of-purchase intervention for coffee shops that reduced the calorie content of customers' purchases by reducing the need for executive function (EF) at the moment of choice. Key facets of EF were identified by a multidisciplinary group and used to develop a point-of-purchase intervention (signage). This intervention was evaluated in a randomized controlled trial (RCT) in a public coffee shop on consumer purchases of >20,000 snacks and drinks over 12 weeks. A sample of customers (n = 128) was recruited to complete an embedded cross-sectional study measuring EF strength, dietary intentions, typical purchases, and purchases made after exposure to the intervention. The proportion of snack purchases that were high in calorie reduced significantly (t(10) = 2.34, p = .04) in intervention weeks relative to control. High calorie drink purchases were also lower in intervention than control weeks, however, this difference was not significant (t(10) = 1.56, p = .15). On average, customers purchased items containing 66 calories customer behavior increased as EF strength decreased (β = .24, p = .03). The calorie content of cafe purchases can be lowered by reducing the cognitive demands of healthy food choice at the moment of purchase, especially in those with poor EF. Environmental changes like these have the potential to help achieve population weight control. (c) 2015 APA, all rights reserved.

  1. Association between job strain (high demand-low control and cardiovascular disease risk factors among petrochemical industry workers

    Directory of Open Access Journals (Sweden)

    Siamak Poorabdian

    2013-08-01

    Full Text Available Objective: One of the practical models for assessment of stressful working conditions due to job strain is "job demand and control" or Karasek's job strain model. This model explains how adverse physical and psychological effects including cardiovascular disease risk factors can be established due to high work demand. The aim was to investigate how certain cardiovascular risk factors including body mass index (BMI, heart rate, blood pressure, serum total cholesterol levels, and cigarette smoking are associated with job demand and control in workers. Materials and Methods: In this cohort study, 500 subjects completed "job demand and control" questionnaires. Factor analysis method was used in order to specify the most important "job demand and control" questions. Health check-up records of the workers were applied to extract data about cardiovascular disease risk factors. Ultimately, hypothesis testing, based on Eta, was used to assess the relationship between separated working groups and cardiovascular risk factors (hypertension and serum total cholesterol level. Results: A significant relationship was found between the job demand-control model and cardiovascular risk factors. In terms of chisquared test results, the highest value was assessed for heart rate (Chi2 = 145.078. The corresponding results for smoking and BMI were Chi2 = 85.652 and Chi2 = 30.941, respectively. Subsequently, Eta result for total cholesterol was 0.469, followed by hypertension equaling 0.684. Moreover, there was a significant difference between cardiovascular risk factors and job demand-control profiles among different working groups including the operational group, repairing group and servicing group. Conclusion: Job control and demand are significantly related to heart disease risk factors including hypertension, hyperlipidemia, and cigarette smoking.

  2. Predictive Control of a Domestic Freezer for Real-Time Demand Response Applications

    NARCIS (Netherlands)

    Baghina, N.G.; Lampropoulos, I.; Asare-Bediako, B.; Kling, W.L.; Ribeiro, P.F.

    2012-01-01

    Demand side management and demand response aim to maximize the efficiency of the electricity delivery process by exploiting the flexibility of customers. At residential level, demand response can be applied only to a limited number of appliances, through load management, due to user intervention or

  3. Time management behavior as a moderator for the job demand-control interaction

    NARCIS (Netherlands)

    Peeters, M.A.G.; Rutte, C.G.

    2005-01-01

    The interaction effects of time management, work demands, and autonomy on burnout were investigated in a survey study of 123 elementary teachers. A 3-way interaction between time management, work demands, and autonomy was hypothesized: The combination of high work demands and low autonomy was

  4. SU-F-P-13: NRG Oncology Medical Physics Manpower Survey Quantifying Support Demands for Multi Institutional Clinical Trials

    Energy Technology Data Exchange (ETDEWEB)

    Monroe, J [St. Anthony’s Cancer Center, St. Louis, MO (United States); Case Western Reserve University (United States); Boparai, K [ACR, Reston, VA (United States); Xiao, Y [University of Pennsylvania, Philadelphia, PA (United States); Followill, D [UT MD Anderson Cancer Center, Houston, TX (United States); Galvin, J [Thomas Jefferson University Hospital, Newtown, PA (United States); Sohn, J [Case Western University, Cleveland, OH (United States)

    2016-06-15

    Purpose: A survey was taken by NRG Oncology to assess Full Time Equivalent (FTE) contributions to multi institutional clinical trials by medical physicists.No current quantification of physicists’ efforts in FTE units associated with clinical trials is available. The complexity of multi-institutional trials increases with new technologies and techniques. Proper staffing may directly impact the quality of trial data and outcomes. The demands on physics time supporting clinical trials needs to be assessed. Methods: The NRG Oncology Medical Physicist Subcommittee created a sixteen question survey to obtain this FTE data. IROC Houston distributed the survey to their list of 1802 contact physicists. Results: After three weeks, 363 responded (20.1% response). 187 (51.5%) institutions reporting external beam participation were processed. There was a wide range in number of protocols active and supported at each institution. Of the 187 clinics, 134 (71.7%) participate in 0 to 10 trials, 28 (15%) in 11 to 20 trials, 10 (5.3%) in 21 to 30 trials, 9 (4.8%) had 40 to 75 trials. On average, physicist spent 2.7 hours (SD: 6.0) per week supervising or interacting with clinical trial staff. 1.25 hours (SD: 3.37), 1.83 hours (SD: 4.13), and 0.64 hours(SD: 1.13) per week were spent on patient simulation, reviewing treatment plans, and maintaining a DICOM server, respectively. For all protocol credentialing activities, physicist spent an average of 37.05 hours (SD: 96.94) yearly. To support dosimetrists, clinicians, and therapists, physicist spend on average 2.07 hours (SD: 3.52) per week just reading protocols. Physicist attended clinical trial meetings for on average 1.13 hours (SD: 1.85) per month. Conclusion: Responding physicists spend a nontrivial amount of time: 8.8 hours per week (0.22 FTE) supporting, on average, 9 active multi-institutional clinical trials.

  5. Impact of thermostatically controlled loads' demand response activation on aggregated power: A field experiment

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Kosek, Anna Magdalena

    2015-01-01

    activation. The outcome of this experimental study quantifies the actual flexibility of household TCLs and the consequence for the different parties with respect to power behaviour. Each DR activation method adopts different scenarios to meet the power reduction, and has different impacts on the parameters......This paper describes the impacts of different types of DR (demand response) activation on TCLs' (thermostatically controlled loads) aggregated power. The different parties: power system operators, DR service providers (or aggregators) and consumers, have different objectives in relation to DR....... The experiments are conducted with real domestic refrigerators representing TCL. Activating refrigerators for DR with a delay reduces the ISE (integral square error) in power limitation by 28.46%, overshoot by 7.69%. The delay in refrigerator activation causes reduction in power ramp down rate by 39.90%, ramp up...

  6. On-demand semiconductor source of 780-nm single photons with controlled temporal wave packets

    Science.gov (United States)

    Béguin, Lucas; Jahn, Jan-Philipp; Wolters, Janik; Reindl, Marcus; Huo, Yongheng; Trotta, Rinaldo; Rastelli, Armando; Ding, Fei; Schmidt, Oliver G.; Treutlein, Philipp; Warburton, Richard J.

    2018-05-01

    We report on a fast, bandwidth-tunable single-photon source based on an epitaxial GaAs quantum dot. Exploiting spontaneous spin-flip Raman transitions, single photons at 780 nm are generated on demand with tailored temporal profiles of durations exceeding the intrinsic quantum dot lifetime by up to three orders of magnitude. Second-order correlation measurements show a low multiphoton emission probability [g2(0 ) ˜0.10 -0.15 ] at a generation rate up to 10 MHz. We observe Raman photons with linewidths as low as 200 MHz, which is narrow compared to the 1.1-GHz linewidth measured in resonance fluorescence. The generation of such narrow-band single photons with controlled temporal shapes at the rubidium wavelength is a crucial step towards the development of an optimized hybrid semiconductor-atom interface.

  7. Effects of preventive versus "on-demand" nutritional support on paid labour productivity, physical exercise and performance status during PEG-interferon-containing treatment for hepatitis C.

    Science.gov (United States)

    Huisman, Ellen J; van Meer, Suzanne; van Hoek, Bart; van Soest, Hanneke; van Nieuwkerk, Karin M J; Arends, Joop E; Siersema, Peter D; van Erpecum, Karel J

    2016-04-01

    Deterioration of nutritional status during PEG-interferon containing therapy for chronic hepatitis C can be ameliorated by preventive nutritional support. We aimed to explore whether such support also affects paid labour productivity, physical exercise and performance status. In this prospective randomized controlled trial (J Hepatol 2012;57:1069-75), 53 patients with chronic hepatitis C had been allocated to "on demand" support (n=26: nutritional intervention if weight loss>5%) or preventive support (n=27: regular dietary advice plus energy- and protein-rich evening snack) during PEG-interferon-containing therapy. Paid labour productivity, physical exercise and performance status were evaluated at baseline, after 24 and (if applicable) after 48 weeks of treatment. At baseline, 46% of patients performed paid labour and 62% performed some kind of physical exercise. Furthermore, most patients were able to carry out normal activity with only minor symptoms of disease (mean Karnofsky performance score: 94). Decreases of paid labour productivity (-21% vs. -70%, P=0.003), physical exercise activity (-43% vs. -87%, P=0.005) and Karnofsky performance scores (-12% vs. -24%, Plabour productivity, physical exercise and performance status during PEG-interferon-containing treatment for chronic hepatitis C. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  8. Field Testing of Telemetry for Demand Response Control of Small Loads

    Energy Technology Data Exchange (ETDEWEB)

    Lanzisera, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Weber, Adam [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liao, Anna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schetrit, Oren [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Piette, Mary Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2018-01-30

    The electricity system in California, from generation through loads, must be prepared for high renewable penetration and increased electrification of end uses while providing increased resilience and lower operating cost. California has an aggressive renewable portfolio standard that is complemented by world-leading greenhouse gas goals. The goal of this project was to evaluate methods of enabling fast demand response (DR) signaling to small loads for low-cost site enablement. We used OpenADR 2.0 to meet telemetry requirements for providing ancillary services, and we used a variety of low-cost devices coupled with open-source software to enable an end-to-end fast DR. The devices, architecture, implementation, and testing of the system is discussed in this report. We demonstrate that the emerging Internet of Things (IoT) and Smart Home movements provide an opportunity for diverse small loads to provide fast, low-cost demand response. We used Internet-connected lights, thermostats, load interruption devices, and water heaters to demonstrate an ecosystem of controllable devices. The system demonstrated is capable of providing fast load shed for between 20 dollars and $300 per kilowatt (kW) of available load. The wide range results from some loads may have very low cost but also very little shed capability (a 10 watt [W] LED light can only shed a maximum of 10 W) while some loads (e.g., water heaters or air conditioners) can shed several kilowatts but have a higher initial cost. These costs, however, compare well with other fast demand response costs, with typically are over $100/kilowatt of shed. We contend these loads are even more attractive than their price suggests because many of them will be installed for energy efficiency or non-energy benefits (e.g., improved lighting quality or controllability), and the ability to use them for fast DR is a secondary benefit. Therefore the cost of enabling them for DR may approach zero if a software-only solution can be

  9. Expert ratings of job demand and job control as predictors of injury and musculoskeletal disorder risk in a manufacturing cohort.

    Science.gov (United States)

    Cantley, Linda F; Tessier-Sherman, Baylah; Slade, Martin D; Galusha, Deron; Cullen, Mark R

    2016-04-01

    To examine associations between workplace injury and musculoskeletal disorder (MSD) risk and expert ratings of job-level psychosocial demand and job control, adjusting for job-level physical demand. Among a cohort of 9260 aluminium manufacturing workers in jobs for which expert ratings of job-level physical and psychological demand and control were obtained during the 2 years following rating obtainment, multivariate mixed effects models were used to estimate relative risk (RR) of minor injury and minor MSD, serious injury and MSD, minor MSD only and serious MSD only by tertile of demand and control, adjusting for physical demand as well as other recognised risk factors. Compared with workers in jobs rated as having low psychological demand, workers in jobs with high psychological demand had 49% greater risk of serious injury and serious MSD requiring medical treatment, work restrictions or lost work time (RR=1.49; 95% CI 1.10 to 2.01). Workers in jobs rated as having low control displayed increased risk for minor injury and minor MSD (RR=1.45; 95% CI 1.12 to 1.87) compared with those in jobs rated as having high control. Using expert ratings of job-level exposures, this study provides evidence that psychological job demand and job control contribute independently to injury and MSD risk in a blue-collar manufacturing cohort, and emphasises the importance of monitoring psychosocial workplace exposures in addition to physical workplace exposures to promote worker health and safety. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. Model-on-Demand Predictive Control for Nonlinear Hybrid Systems With Application to Adaptive Behavioral Interventions

    Science.gov (United States)

    Nandola, Naresh N.; Rivera, Daniel E.

    2011-01-01

    This paper presents a data-centric modeling and predictive control approach for nonlinear hybrid systems. System identification of hybrid systems represents a challenging problem because model parameters depend on the mode or operating point of the system. The proposed algorithm applies Model-on-Demand (MoD) estimation to generate a local linear approximation of the nonlinear hybrid system at each time step, using a small subset of data selected by an adaptive bandwidth selector. The appeal of the MoD approach lies in the fact that model parameters are estimated based on a current operating point; hence estimation of locations or modes governed by autonomous discrete events is achieved automatically. The local MoD model is then converted into a mixed logical dynamical (MLD) system representation which can be used directly in a model predictive control (MPC) law for hybrid systems using multiple-degree-of-freedom tuning. The effectiveness of the proposed MoD predictive control algorithm for nonlinear hybrid systems is demonstrated on a hypothetical adaptive behavioral intervention problem inspired by Fast Track, a real-life preventive intervention for improving parental function and reducing conduct disorder in at-risk children. Simulation results demonstrate that the proposed algorithm can be useful for adaptive intervention problems exhibiting both nonlinear and hybrid character. PMID:21874087

  11. Prefrontal cortex activation upon a demanding virtual hand-controlled task: a new frontier for neuroergonomics

    Directory of Open Access Journals (Sweden)

    Marika eCarrieri

    2016-02-01

    Full Text Available Functional near-infrared spectroscopy (fNIRS is a non-invasive vascular-based functional neuroimaging technology that can assess, simultaneously from multiple cortical areas, concentration changes in oxygenated-deoxygenated hemoglobin at the level of the cortical microcirculation blood vessels. fNIRS, with its high degree of ecological validity and its very limited requirement of physical constraints to subjects, could represent a valid tool for monitoring cortical responses in the research field of neuroergonomics. In virtual reality (VR real situations can be replicated with greater control than those obtainable in the real world. Therefore, VR is the ideal setting where studies about neuroergonomics applications can be performed. The aim of the present study was to investigate, by a 20-channel fNIRS system, the dorsolateral/ventrolateral prefrontal cortex (DLPFC/VLPFC in subjects while performing a demanding VR hand-controlled task (HCT. Considering the complexity of the HCT, its execution should require the attentional resources allocation and the integration of different executive functions. The HCT simulates the interaction with a real, remotely-driven, system operating in a critical environment. The hand movements were captured by a high spatial and temporal resolution 3D hand-sensing device, the LEAP motion controller, a gesture-based control interface that could be used in VR for tele-operated applications. Fifteen University students were asked to guide, with their right hand/forearm, a virtual ball (VB over a virtual route (VROU reproducing a 42-m narrow road including some critical points. The subjects tried to travel as long as possible without making VB fall. The distance traveled by the guided VB was 70.2±37.2 m. The less skilled subjects failed several times in guiding the VB over the VROU. Nevertheless, a bilateral VLPFC activation, in response to the HCT execution, was observed in all the subjects. No correlation was found

  12. Prefrontal Cortex Activation Upon a Demanding Virtual Hand-Controlled Task: A New Frontier for Neuroergonomics.

    Science.gov (United States)

    Carrieri, Marika; Petracca, Andrea; Lancia, Stefania; Basso Moro, Sara; Brigadoi, Sabrina; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentina

    2016-01-01

    Functional near-infrared spectroscopy (fNIRS) is a non-invasive vascular-based functional neuroimaging technology that can assess, simultaneously from multiple cortical areas, concentration changes in oxygenated-deoxygenated hemoglobin at the level of the cortical microcirculation blood vessels. fNIRS, with its high degree of ecological validity and its very limited requirement of physical constraints to subjects, could represent a valid tool for monitoring cortical responses in the research field of neuroergonomics. In virtual reality (VR) real situations can be replicated with greater control than those obtainable in the real world. Therefore, VR is the ideal setting where studies about neuroergonomics applications can be performed. The aim of the present study was to investigate, by a 20-channel fNIRS system, the dorsolateral/ventrolateral prefrontal cortex (DLPFC/VLPFC) in subjects while performing a demanding VR hand-controlled task (HCT). Considering the complexity of the HCT, its execution should require the attentional resources allocation and the integration of different executive functions. The HCT simulates the interaction with a real, remotely-driven, system operating in a critical environment. The hand movements were captured by a high spatial and temporal resolution 3-dimensional (3D) hand-sensing device, the LEAP motion controller, a gesture-based control interface that could be used in VR for tele-operated applications. Fifteen University students were asked to guide, with their right hand/forearm, a virtual ball (VB) over a virtual route (VROU) reproducing a 42 m narrow road including some critical points. The subjects tried to travel as long as possible without making VB fall. The distance traveled by the guided VB was 70.2 ± 37.2 m. The less skilled subjects failed several times in guiding the VB over the VROU. Nevertheless, a bilateral VLPFC activation, in response to the HCT execution, was observed in all the subjects. No correlation was found

  13. Demand specifying variables and current ventilation rate requirements with respect to the future use of voc sensing for dcv control

    DEFF Research Database (Denmark)

    Kolarik, Jakub

    be also taken into account in the ventilation control. Recent development in gas sensing technology resulted in a new generation of relatively cheap and practically applicable sensors that can offer measurements of some of the pollutants mentioned above – mainly Volatile Organic Compounds (VOC......Demand Controlled Ventilation (DCV) is a well established principle to provide a certain indoor environmental quality, defined both in the terms of air quality and thermal comfort. This is accomplished by adjusting the supplied airflow rate according to a certain demand indicator, which......). This seems to bring a new dimension into the control of DCV systems. This paper is a contribution to the workshop on utilization of VOC sensing technology used for DCV control. The aim of the paper is to provide a short review of different types of demand variables used to control DCV systems and summarize...

  14. Peroxone mineralization of chemical oxygen demand for direct potable water reuse: Kinetics and process control.

    Science.gov (United States)

    Wu, Tingting; Englehardt, James D

    2015-04-15

    Mineralization of organics in secondary effluent by the peroxone process was studied at a direct potable water reuse research treatment system serving an occupied four-bedroom, four bath university residence hall apartment. Organic concentrations were measured as chemical oxygen demand (COD) and kinetic runs were monitored at varying O3/H2O2 dosages and ratios. COD degradation could be accurately described as the parallel pseudo-1st order decay of rapidly and slowly-oxidizable fractions, and effluent COD was reduced to below the detection limit (<0.7 mg/L). At dosages ≥4.6 mg L(-1) h(-1), an O3/H2O2 mass ratio of 3.4-3.8, and initial COD <20 mg/L, a simple first order decay was indicated for both single-passed treated wastewater and recycled mineral water, and a relationship is proposed and demonstrated to estimate the pseudo-first order rate constant for design purposes. At this O3/H2O2 mass ratio, ORP and dissolved ozone were found to be useful process control indicators for monitoring COD mineralization in secondary effluent. Moreover, an average second order rate constant for OH oxidation of secondary effluent organics (measured as MCOD) was found to be 1.24 × 10(7) ± 0.64 × 10(7) M(-1) S(-1). The electric energy demand of the peroxone process is estimated at 1.73-2.49 kW h electric energy for removal of one log COD in 1 m(3) secondary effluent, comparable to the energy required for desalination of medium strength seawater. Advantages/disadvantages of the two processes for municipal wastewater reuse are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Hybrid LSA-ANN Based Home Energy Management Scheduling Controller for Residential Demand Response Strategy

    Directory of Open Access Journals (Sweden)

    Maytham S. Ahmed

    2016-09-01

    Full Text Available Demand response (DR program can shift peak time load to off-peak time, thereby reducing greenhouse gas emissions and allowing energy conservation. In this study, the home energy management scheduling controller of the residential DR strategy is proposed using the hybrid lightning search algorithm (LSA-based artificial neural network (ANN to predict the optimal ON/OFF status for home appliances. Consequently, the scheduled operation of several appliances is improved in terms of cost savings. In the proposed approach, a set of the most common residential appliances are modeled, and their activation is controlled by the hybrid LSA-ANN based home energy management scheduling controller. Four appliances, namely, air conditioner, water heater, refrigerator, and washing machine (WM, are developed by Matlab/Simulink according to customer preferences and priority of appliances. The ANN controller has to be tuned properly using suitable learning rate value and number of nodes in the hidden layers to schedule the appliances optimally. Given that finding proper ANN tuning parameters is difficult, the LSA optimization is hybridized with ANN to improve the ANN performances by selecting the optimum values of neurons in each hidden layer and learning rate. Therefore, the ON/OFF estimation accuracy by ANN can be improved. Results of the hybrid LSA-ANN are compared with those of hybrid particle swarm optimization (PSO based ANN to validate the developed algorithm. Results show that the hybrid LSA-ANN outperforms the hybrid PSO based ANN. The proposed scheduling algorithm can significantly reduce the peak-hour energy consumption during the DR event by up to 9.7138% considering four appliances per 7-h period.

  16. Family demands, social support and caregiver burden in Taiwanese family caregivers living with mental illness: the role of family caregiver gender.

    Science.gov (United States)

    Hsiao, Chiu-Yueh

    2010-12-01

    The purpose of this study was to assess gender effects on family demands, social support and caregiver burden as well as to examine contributing factors of caregiver burden in caring for family members with mental illness. Providing continued care and support for people with mental illness is demanding and challenging. Findings of earlier caregiving studies on the role of caregiver gender in response to caregiver burden and caregiving-related factors have been inconsistent. Little research has been undertaken to examine gender effect on family demands, social support and caregiver burden in Taiwanese family caregivers of individuals with mental illness. Cross-sectional, descriptive correlation design. Data from 43 families, including at least one male and female family caregiver in each family, were analysed using descriptive statistics, principal component analysis and mixed linear modelling. Demographic data, Perceived Stress Scale, Perceived Social Support and Caregiver Burden Scale-Brief were used to collect data. Female family caregivers perceived less social support and experienced higher degrees of caregiver burden compared with male family caregivers. In contrast, no significant gender effect was associated with family demands. Family caregivers with greater family demands and less social support experienced higher degrees of caregiver burden. The results reinforced those of previously published studies that caregiver burden is highly prevalent among female family caregivers. Caregiver gender appears to be highly valuable for explaining family demands, social support and caregiver burden. Health care professionals should continue to collaborate with family caregivers to assess potential gender effects on available support and design gender-specific interventions to alleviate caregiver burden. © 2010 Blackwell Publishing Ltd.

  17. Allocation of reactive power support, active loss balancing and demand interruption ancillary services in MicroGrids

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Mario Helder [Departamento de Engenharia Electrotecnica, Instituto Politecnico de Tomar, Quinta do Contador, Estrada da Serra, 2300 Tomar (Portugal); Saraiva, Joao Tome [INESC Porto and Faculdade de Engenharia da Universidade do Porto, Campus da FEUP, Rua Dr. Roberto Frias, 4200 - 465 Porto (Portugal)

    2010-10-15

    MicroGrids represent a new paradigm for the operation of distribution systems and there are several advantages as well as challenges regarding their development. One of the advantages is related with the participation of MicroGrid agents in electricity markets and in the provision of ancillary services. This paper describes two optimization models to allocate three ancillary services among MicroGrid agents - reactive power/voltage control, active loss balancing and demand interruption. These models assume that MicroGrid agents participate in the day-ahead market sending their bids to the MicroGrid Central Controller, MGCC, that acts as an interface with the Market Operator. Once the Market Operator returns the economic dispatch of the MicroGrid agents, the MGCC checks its technical feasibility (namely voltage magnitude and branch flow limits) and activates an adjustment market to change the initial schedule and to allocate these three ancillary services. One of the models has crisp nature considering that voltage and branch flow limits are rigid while the second one admits that voltage and branch flow limits are modeled in a soft way using Fuzzy Set concepts. Finally, the paper illustrates the application of these models with a Case Study using a 55 node MV/LV network. (author)

  18. Which daily experiences can foster well-being at work? A diary study on the interplay between flow experiences, affective commitment, and self-control demands.

    Science.gov (United States)

    Rivkin, Wladislaw; Diestel, Stefan; Schmidt, Klaus-Helmut

    2018-01-01

    Previous research has provided strong evidence for affective commitment as a direct predictor of employees' psychological well-being and as a resource that buffers the adverse effects of self-control demands as a stressor. However, the mechanisms that underlie the beneficial effects of affective commitment have not been examined yet. Drawing on the self-determination theory, we propose day-specific flow experiences as the mechanism that underlies the beneficial effects of affective commitment, because flow experiences as peaks of intrinsic motivation constitute manifestations of autonomous regulation. In a diary study covering 10 working days with N = 90 employees, we examine day-specific flow experiences as a mediator of the beneficial effects of interindividual affective commitment and a buffering moderator of the adverse day-specific effects of self-control demands on indicators of well-being (ego depletion, need for recovery, work engagement, and subjective vitality). Our results provide strong support for our predictions that day-specific flow experiences a) mediate the beneficial effects of affective commitment on employees' day-specific well-being and b) moderate (buffer) the adverse day-specific effects of self-control demands on well-being. That is, on days with high levels of flow experiences, employees were better able to cope with self-control demands whereas self-control demands translated into impaired well-being when employees experienced lower levels of day-specific flow experiences. We then discuss our findings and suggest practical implications. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  19. Comparative analysis of speed's impact on muscle demands during partial body weight support motor-assisted elliptical training.

    Science.gov (United States)

    Burnfield, Judith M; Irons, Sonya L; Buster, Thad W; Taylor, Adam P; Hildner, Gretchen A; Shu, Yu

    2014-01-01

    Individuals with walking limitations often experience challenges engaging in functionally relevant exercise. An adapted elliptical trainer (motor to assist pedal movement, integrated body weight harness, ramps/stairs, and grab rails) has been developed to help individuals with physical disabilities and chronic conditions regain/retain walking capacity and fitness. However, limited published studies are available to guide therapeutic interventions. This repeated measures study examined the influence of motor-assisted elliptical training speed on lower extremity muscle demands at four body weight support (BWS) levels commonly used therapeutically for walking. Electromyography (EMG) and pedal trajectory data were recorded as ten individuals without known disability used the motor-assisted elliptical trainer at three speeds [20,40, 60 revolutions per minute (RPM)] during each BWS level (0%, 20%, 40%, 60%). Overall, the EMG activity (peak, mean, duration) in key stabilizer muscles (i.e., gluteus medius, gluteus maximus, vastus lateralis, medial gastrocnemius and soleus) recorded at 60 RPM exceeded those at 40 RPM, which were higher than values at 20 RPM in all but three situations (gluteus medius mean at 0% BWS, vastus lateralis mean at 20% BWS, soleus duration at 40% BWS); however, these differences did not always achieve statistical significance. Slower motor-assisted speeds can be used to accommodate weakness of gluteus medius, gluteus maximus, vastus lateralis, medial gastrocnemius and soleus. As strength improves, training at faster motor-assisted speeds may provide a means to progressively challenge key lower extremity stabilizers. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. A Web Based Educational Programming Logic Controller Training Set Based on Vocational High School Students' Demands

    Directory of Open Access Journals (Sweden)

    Abdullah Alper Efe

    2018-01-01

    Full Text Available The purpose of this study was to design and develop aProgramming Logic Controller Training Set according to vocational high school students’ educational needs. In this regard, by using the properties of distance education the proposed system supported “hands-on” PLC programming laboratory exercises in industrial automation area. The system allowed students to access and control the PLC training set remotely. For this purpose, researcher designed a web site to facilitate students’ interactivity and support PLC programming. In the training set, Induction Motor, Frequency Converter and Encoder tripart controlled by Siemens Simatic S7-200 PLC controller by the help of SIMATIC Step 7 Programming Software were used to make the system more effective and efficient. Moreover, training set included an IP camera system allowing to monitor devices and pilot application. By working with this novel remote accessible training set, students and researchers recieved a chance to inhere self paced learning experiences. Also, The PLC training set offered an effective learning enviroenment for distance education, which is based on presenting the content on the web and opening it to the online users and provided a safe and economical solution for multiple users in a workplace to enhance the quality of education with less overall cost.

  1. Demand-based maintenance and operators support based on process models; Behovsstyrt underhaall och operatoersstoed baserat paa process modeller

    Energy Technology Data Exchange (ETDEWEB)

    Dahlquist, Erik; Widarsson, Bjoern; Tomas-Aparicio, Elena

    2012-02-15

    There is a strong demand for systems that can give early warnings on upcoming problems in process performance or sensor measurements. In this project we have developed and implemented such a system on-line. The goal with the system is to give warnings about both faults needing urgent actions, as well giving advice on roughly when service may be needed for specific functions. The use of process simulation models on-line can offer a significant tool for operators and process engineers to analyse the performance of the process and make the most correct and fastest decision when problems arise. In this project physical simulation models are used in combination with decision support tools. By using a physical model it is possible to compare the measured data to the data obtained from the simulation and give these deviations as input to a decision support tool with Bayesian Networks (BN) that will result in information about the probability for wrong measurement in the instruments, process problems and maintenance needs. The application has been implemented in a CFB boiler at Maelarenergi AB. After tuning the model the system has been used online during September - October 2010 and May - October 2011, showing that the system is working on-line with respect to running the simulation model but with batch runs with respect to the BN. Examples have been made for several variables where trends of the deviation between simulation results and measured data have been used as input to a BN, where the probability for different faults has been calculated. Combustion up in the separator/cyclones has been detected several times, problems with fuel feed on both sides of the boiler as well. A moisture sensor not functioning as it should and suspected malfunctioning temperature meters as well. Deeper investigations of the true cause of problems have been used as input to tune the BN

  2. Core-control assembly with a fixed fuel support

    International Nuclear Information System (INIS)

    Challberg, R.C.

    1993-01-01

    A core-control assembly is described comprising: a control rod having a plurality of blades; a control-rod guide tube for guiding vertical motion of said control rod; a fuel support for supporting fuel bundles separated by said blades, said fuel support having an aperture conforming to a cross section of said control rod through said blades for preventing rotational movement of said control rod to a decoupling orientation when said control rod is between a maximum power position and a minimum power position, said minimum power position being above said maximum power position, said fuel support being supported by said control-rod guide tube; control-rod drive means for controlling vertical motion of said control rod, said control-rod drive means providing for vertical motion between said maximum power position and said minimum power position, said control-rod drive means providing for vertical movement to a decoupling position, said decoupling position being no lower than said minimum power position, said decoupling position being at a level sufficient to permit said control rod to rotate to a decoupling orientation relative to said fuel support; and coupling means for coupling said control rod to said control rod drive means, said coupling means being releasable by rotational movement of said control rod to said decoupling orientation relative to said control-rod drive means

  3. Inventory control for a perishable product with non-stationary demand and service level constraints

    NARCIS (Netherlands)

    Pauls-Worm, K.G.J.; Hendrix, E.M.T.; Haijema, R.; Vorst, van der J.G.A.J.

    2013-01-01

    We study the practical production planning problem of a food producer facing a non-stationary erratic demand for a perishable product with a fixed life time. In meeting the uncertain demand, the food producer uses a FIFO issuing policy. The food producer aims at meeting a certain service level at

  4. Differential effects of decision latitude and control on the job demands-strain relationship: a cross-sectional survey study among elderly care nursing staff.

    Science.gov (United States)

    Schmidt, Klaus-Helmut; Diestel, Stefan

    2011-03-01

    According to the influential Job Demands-Control (JD-C) model developed by Karasek (1979; Karasek and Theorell, 1990), job strain is expected to result from high job demands and low job control as well as an interaction between both job characteristics. Previous research, however, has found such an interaction only rarely or inconsistently.It has been suggested that the conceptualization of the control variable (formerly referred to as decision latitude) may be particularly responsible for the lack of supportive findings. The present study aimed at clarifying this issue by contrasting a focused measure of control with a traditional measure of decision latitude in their relations to job strain of health care workers. The measure of decision latitude encompassed a wide range of job characteristics including control, task variety, and learning opportunities. A cross-sectional questionnaire survey was conducted with job satisfaction, psychosomatic complaints and emotional exhaustion as criterion measures of job strain. A supra-regional organization for residential elderly care with 11 nursing homes located in a federal state in Germany. Questionnaires were distributed to the whole nursing staff, of which 379 filled in the questionnaire during normal working hours (68% participation rate). In addition to confirmatory factor analyses, descriptive statistics, and bivariate correlations, hierarchical multiple regression analyses were performed for testing the corresponding interaction effects. Findings confirmed the assumption that the focused measure of control and the traditional measure of decision latitude represent distinct, yet correlated factors. Furthermore, findings revealed a significant interaction effect between job demands and control on all outcomes considered. By way of contrast, there was no equivalent interaction effect between job demands and decision latitude. In line with the JD-C model, the adverse influence of increasing demands on job satisfaction

  5. Work-related stress according to the demand-control model and minor psychic disorders in nursing workers

    Directory of Open Access Journals (Sweden)

    Janete de Souza Urbanetto

    2013-10-01

    Full Text Available This was a cross-sectional study that aimed to assess the association between work-related stress according to the Demand-Control Model, and the occurrence of Minor Psychic Disorder (MPD in nursing workers. The participants were 335 professionals, out of which 245 were nursing technicians, aged predominantly between 20 and 40 years. Data were collected using the Job Stress Scale and the Self-Reporting Questionnaire-20. The analysis was performed using descriptive and analytical statistics. The prevalence of suspected MPD was 20.6%. Workers classified in the quadrants active job and high strain of the Demand-Control Model presented higher potential for developing MPD compared with those classified in the quadrant low strain. In conclusion, stress affects the mental health of workers and the aspects related to high psychological demands and high control still require further insight in order to understand their influence on the disease processes of nursing workers.

  6. Quantifying demand flexibility of power-to-heat and thermal energy storage in the control of building heating systems

    DEFF Research Database (Denmark)

    Finck, Christian; Li, Rongling; Kramer, Rick

    2018-01-01

    restricted by power-to-heat conversion such as heat pumps and thermal energy storage possibilities of a building. To quantify building demand flexibility, it is essential to capture the dynamic response of the building energy system with thermal energy storage. To identify the maximum flexibility a building......’s energy system can provide, optimal control is required. In this paper, optimal control serves to determine in detail demand flexibility of an office building equipped with heat pump, electric heater, and thermal energy storage tanks. The demand flexibility is quantified using different performance...... of TES and power-to-heat in any case of charging, discharging or idle mode. A simulation case study is performed showing that a water tank, a phase change material tank, and a thermochemical material tank integrated with building heating system can be designed to provide flexibility with optimal control....

  7. Policy of energy demand control and resistance to change. A socio-anthropological approach

    International Nuclear Information System (INIS)

    Zelem, Marie-Christine

    2010-03-01

    The development of energy consuming devices, the growth of electricity consumptions, the exhaustion of fossil fuels and the increase of greenhouse gases are as many factors that contribute to the acceleration of global warming. The control of energy demand is one of the levers to influence the energy-consuming behaviours. What are such policies made of? What instruments are used and with what efficiency? What population is targeted? Using some practical examples taken in the everyday life, the first part of this book shows how professionals and consumers are reticent to change their habits, equipments and know-how, and why they have very good reasons to do so. The second part of the book treats of incentive systems and shows that they very often have problems with finding a public. The different energy saving awareness campaigns show the importance of the preliminary building of an energy saving culture to make energy saving policies efficient and socially acceptable. The next part deals with the experience gained from the energy efficiency programs implemented in Quebec and in French Guyana. In both cases, the public information tools are adapted to the culture of the targeted populations. The last part reviews some paths to explore to durably change the behaviours. (J.S.)

  8. Control Systems Cyber Security Standards Support Activities

    Energy Technology Data Exchange (ETDEWEB)

    Robert Evans

    2009-01-01

    The Department of Homeland Security’s Control Systems Security Program (CSSP) is working with industry to secure critical infrastructure sectors from cyber intrusions that could compromise control systems. This document describes CSSP’s current activities with industry organizations in developing cyber security standards for control systems. In addition, it summarizes the standards work being conducted by organizations within the sector and provides a brief listing of sector meetings and conferences that might be of interest for each sector. Control systems cyber security standards are part of a rapidly changing environment. The participation of CSSP in the development effort for these standards has provided consistency in the technical content of the standards while ensuring that information developed by CSSP is included.

  9. Controlling the demand for electricity: strategies and challenges in the residential sector of the OECD countries

    International Nuclear Information System (INIS)

    Lebot, B.

    2003-01-01

    By reinforcing policies to improve the energy efficiency of household appliances (particularly by rating the efficiency of each appliance as a minimum of its overall cost from 2005 onwards), the member countries of the IEA are in a position to reduce their annual CO 2 emissions by approximately 322 million tonnes (Mt) by 2010, compared to what they would have obtained using current policies. In 2030, this same policy will make it possible to achieve an annual saving of 1 110 TWh in the consumption of electricity, (572 Mt of CO 2 each year). This measure alone will meet 30% of the objectives of the member countries of the IEA under the Kyoto agreements concerning climatic change. These reductions can be obtained at a negative cost for society as the additional cost generated by improvements in energy efficiency is offset by savings made in operating costs during the life of the appliance. Thus, in the United States, each tonne of CO 2 saved in this way in 2020 will generate $65 for society. In Europe, every tonne of CO 2 saved will generate a gain of euros 169 (the difference being accounted for by the higher cost of electricity and by lower energy efficiency standards currently existing in Europe). It is possible to make major savings in all regions of the OECD, despite the vast diversity of the various situations of the countries. In the member countries of the IEA, the policies in place have already demonstrated their economic effectiveness in reducing demand for energy and greenhouse gas emissions. Up to 2000, they made it possible to reduce greenhouse gas emissions by approximately 46 Mt of CO 2 each year. These policies will contribute to reducing emissions by 126 Mt of CO 2 each year up to 2010. International co-operation offers real advantages in the deployment of policies for controlling the demand for energy by households. Manufacturers, consumers and governments all benefit from greater transparency in the marketplace, improved comparisons of test methods

  10. Professional efficacy, exhaustion, and work characteristics among police officers: A longitudinal test of the learning-related predictions of the demand-control model

    NARCIS (Netherlands)

    Taris, T.W.; Kompier, M.A.J.; Geurts, S.A.E.; Houtman, I.L.D.; Heuvel, F.F.M. van den

    2010-01-01

    The present study addressed the relationships among professional efficacy, emotional exhaustion, and job characteristics (job demands and job control) in the context of a two-wave panel study among 828 Dutch police officers. Based on the demand-control model, we expected that high demands/high

  11. Physical activity, job demand-control, perceived stress-energy, and salivary cortisol in white-collar workers

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Blangsted, Anne Katrine; Hansen, Ernst Albin

    2010-01-01

    The aim of the present study is to examine the association between physical activity and perceived job demand, job control, perceived stress and energy, and physiological arousal reflected by morning and evening concentrations of cortisol in saliva among white-collar workers.......The aim of the present study is to examine the association between physical activity and perceived job demand, job control, perceived stress and energy, and physiological arousal reflected by morning and evening concentrations of cortisol in saliva among white-collar workers....

  12. Time management behavior as a moderator for the job demand-control interaction.

    Science.gov (United States)

    Peeters, Miranda A G; Rutte, Christel G

    2005-01-01

    The interaction effects of time management, work demands, and autonomy on burnout were investigated in a survey study of 123 elementary teachers. A 3-way interaction between time management, work demands, and autonomy was hypothesized: The combination of high work demands and low autonomy was predicted to lead to burnout for teachers low in time management and not, or to a lesser extent, for those high in time management. This hypothesis is confirmed for emotional exhaustion, the most predictive dimension of teacher burnout, and partly confirmed for the personal accomplishment dimension. Generalizability to other contactual occupations is discussed. ((c) 2005 APA, all rights reserved).

  13. Individual Characteristics Influencing Physicians’ Perceptions of Job Demands and Control: The Role of Affectivity, Work Engagement and Workaholism

    Directory of Open Access Journals (Sweden)

    Greta Mazzetti

    2016-06-01

    Full Text Available The first purpose of the present study was to investigate the role of individual characteristics, i.e., positive and negative affectivity, in explaining the different perception of job control and job demands in a particularly demanding environment such as the healthcare setting. In addition, we aimed to explore the mediational role of work engagement and workaholism using the Job Demands-Resources Model as a theoretical framework. Data were collected using a sample of 269 Italian head physicians working in nine general hospitals. To test our hypotheses, the collected data were analyzed with structural equation modeling. Moreover, Sobel Test and bootstrapping were employed to assess the mediating hypotheses. Our results indicated that positive affectivity is related to work engagement, which, in its turn, showed a positive association with job control. In addition, workaholism mediated the relationship between negative affectivity and job demands. All in all, this study represents a first attempt to explore the role of trait affectivity as a dispositional characteristic able to foster the level of work engagement and workaholism exhibited by employees and, in turn, to increase the perceived levels of job control and job demands.

  14. Individual Characteristics Influencing Physicians' Perceptions of Job Demands and Control: The Role of Affectivity, Work Engagement and Workaholism.

    Science.gov (United States)

    Mazzetti, Greta; Biolcati, Roberta; Guglielmi, Dina; Vallesi, Caryn; Schaufeli, Wilmar B

    2016-06-06

    The first purpose of the present study was to investigate the role of individual characteristics, i.e., positive and negative affectivity, in explaining the different perception of job control and job demands in a particularly demanding environment such as the healthcare setting. In addition, we aimed to explore the mediational role of work engagement and workaholism using the Job Demands-Resources Model as a theoretical framework. Data were collected using a sample of 269 Italian head physicians working in nine general hospitals. To test our hypotheses, the collected data were analyzed with structural equation modeling. Moreover, Sobel Test and bootstrapping were employed to assess the mediating hypotheses. Our results indicated that positive affectivity is related to work engagement, which, in its turn, showed a positive association with job control. In addition, workaholism mediated the relationship between negative affectivity and job demands. All in all, this study represents a first attempt to explore the role of trait affectivity as a dispositional characteristic able to foster the level of work engagement and workaholism exhibited by employees and, in turn, to increase the perceived levels of job control and job demands.

  15. Control Method for Variable Speed Wind Turbines to Support Temporary Primary Frequency Control

    DEFF Research Database (Denmark)

    Wang, Haijiao; Chen, Zhe; Jiang, Quanyuan

    2014-01-01

    This paper develops a control method for variable speed wind turbines (VSWTs) to support temporary primary frequency control of power system. The control method contains two parts: (1) up-regulate support control when a frequency drop event occurs; (2) down-regulate support control when a frequen...

  16. Active Control of Thermostatic Loads for Economic and Technical Support to Distribution Grids

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Mendaza, Iker Diaz de Cerio; Bak-Jensen, Birgitte

    2016-01-01

    Active control of electric water heaters (EWHs) is presented in this paper as a means of exploiting demand flexibility for supporting low-voltage (LV) distribution grids. A single-node model of an EWH is implemented in DIgSILENT PowerFactory using a thermal energy balancing equation and three...... decentralized control schemes are designed to ensure consumer comfort, economic benefit to the consumer, and technical support to LV grids. First, a price-based control that adaptively adjusts an allowable energy band per electricity price is implemented to ensure economic benefit. Next, an adaptive update...... of the energy band is done based on feeder loading to respect thermal grid constraints. Finally, a voltage-based control is implemented to provide real-time voltage support to the LV grids. Simulation results demonstrate the capability of the presented method to realize both economic and technical advantages...

  17. The influence of an auditory-memory attention-demanding task on postural control in blind persons.

    Science.gov (United States)

    Melzer, Itshak; Damry, Elad; Landau, Anat; Yagev, Ronit

    2011-05-01

    In order to evaluate the effect of an auditory-memory attention-demanding task on balance control, nine blind adults were compared to nine age-gender-matched sighted controls. This issue is particularly relevant for the blind population in which functional assessment of postural control has to be revealed through "real life" motor and cognitive function. The study aimed to explore whether an auditory-memory attention-demanding cognitive task would influence postural control in blind persons and compare this with blindfolded sighted persons. Subjects were instructed to minimize body sway during narrow base upright standing on a single force platform under two conditions: 1) standing still (single task); 2) as in 1) while performing an auditory-memory attention-demanding cognitive task (dual task). Subjects in both groups were required to stand blindfolded with their eyes closed. Center of Pressure displacement data were collected and analyzed using summary statistics and stabilogram-diffusion analysis. Blind and sighted subjects had similar postural sway in eyes closed condition. However, for dual compared to single task, sighted subjects show significant decrease in postural sway while blind subjects did not. The auditory-memory attention-demanding cognitive task had no interference effect on balance control on blind subjects. It seems that sighted individuals used auditory cues to compensate for momentary loss of vision, whereas blind subjects did not. This may suggest that blind and sighted people use different sensorimotor strategies to achieve stability. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Salivary a-Amylase Reflects Change in Attentional Demands during Postural Control: Comparison with Probe Reaction Time

    Science.gov (United States)

    Akizuki, Kazunori; Ohashi, Yukari

    2014-01-01

    Purpose: The influence of attention on postural control and the relationship between attention and falling has been reported in previous studies. Although a dual-task procedure is commonly used to measure attentional demand, such procedures are affected by allocation policy, which is a mental strategy to divide attention between simultaneous…

  19. Structuring energy supply and demand networks in a general equilibrium model to simulate global warming control strategies

    International Nuclear Information System (INIS)

    Hamilton, S.; Veselka, T.D.; Cirillo, R.R.

    1991-01-01

    Global warming control strategies which mandate stringent caps on emissions of greenhouse forcing gases can substantially alter a country's demand, production, and imports of energy products. Although there is a large degree of uncertainty when attempting to estimate the potential impact of these strategies, insights into the problem can be acquired through computer model simulations. This paper presents one method of structuring a general equilibrium model, the ENergy and Power Evaluation Program/Global Climate Change (ENPEP/GCC), to simulate changes in a country's energy supply and demand balance in response to global warming control strategies. The equilibrium model presented in this study is based on the principle of decomposition, whereby a large complex problem is divided into a number of smaller submodules. Submodules simulate energy activities and conversion processes such as electricity production. These submodules are linked together to form an energy supply and demand network. Linkages identify energy and fuel flows among various activities. Since global warming control strategies can have wide reaching effects, a complex network was constructed. The network represents all energy production, conversion, transportation, distribution, and utilization activities. The structure of the network depicts interdependencies within and across economic sectors and was constructed such that energy prices and demand responses can be simulated. Global warming control alternatives represented in the network include: (1) conservation measures through increased efficiency; and (2) substitution of fuels that have high greenhouse gas emission rates with fuels that have lower emission rates. 6 refs., 4 figs., 4 tabs

  20. Software Support for Industrial Controls Contract

    CERN Document Server

    Sánchez-Corral, E

    2001-01-01

    The contract covers the development and the operation and maintenance (O&M) of the monitoring and control systems used for supervising CERN's technical infrastructure. The contract involves those responsible for equipment in any current or future technical installation. We are outsourcing a complex activity which will require efforts on both preparing the specifications for new projects and setting clear definitions of tasks and procedures for O&M. It is a result-oriented contract in which performance will be continually evaluated by different methods and tools: project management plan and project follow-up, and CAMMS (Computerised Assets and Maintenance Management system). To be used effectively, this approach requires complete traceability of activities and documentation of the systems. Based on the analysis of the results measured and the shared (CERN and contractor) experience, the O&M activities will be reviewed and reorganised and operational procedures will be changed according to needs. A ...

  1. A novel algorithm for demand-control of a single-room ventilation unit with a rotary heat exchanger

    DEFF Research Database (Denmark)

    Smith, Kevin Michael; Jansen, Anders Lund; Svendsen, Svend

    in the indoor environment. Based on these values, a demand-control algorithm varies fan speeds to change airflow rates and varies the rotational speed of the heat exchanger to modulate heat and moisture recovery. The algorithm varies airflow rates to provide free cooling and limit CO2 concentrations and varies...... moisture recovery by varying the rotational speed and then safely unbalances airflows in a worst-case scenario. In the algorithm, frost protection and minimum supply temperature take the highest priority and override other controls. This paper documents the proposed demand control algorithm and analyses...... its impacts on compliance of building regulations in Denmark. The paper presents an algorithm that manufacturers can program into their controls. The commercially available single-room ventilation unit with a rotary heat exchanger uses this algorithm coded in the C language. Future work will document...

  2. A mismatch between supply and demand of social support in dementia care: a qualitative study on the perspectives of spousal caregivers and their social network members.

    Science.gov (United States)

    Dam, Alieske E H; Boots, Lizzy M M; van Boxtel, Martin P J; Verhey, Frans R J; de Vugt, Marjolein E

    2017-06-13

    Access to social support contributes to feelings of independence and better social health. This qualitative study aims to investigate multi-informant perspectives on informal social support in dementia care networks. Ten spousal caregivers of people with dementia (PwD) completed an ecogram, a social network card and a semi-structured interview. The ecogram aimed to trigger subjective experiences regarding social support. Subsequently, 17 network members were interviewed. The qualitative analyses identified codes, categories, and themes. Sixth themes emerged: (1) barriers to ask for support; (2) facilitators to ask for support; (3) barriers to offer support; (4) facilitators to offer support; (5) a mismatch between supply and demand of social support; and (6) openness in communication to repair the imbalance. Integrating social network perspectives resulted in a novel model identifying a mismatch between the supply and demand of social support, strengthened by a cognitive bias: caregivers reported to think for other social network members and vice versa. Openness in communication in formal and informal care systems might repair this mismatch.

  3. Gender Differences in the Effects of Job Control and Demands on the Health of Korean Manual Workers.

    Science.gov (United States)

    Kim, HeeJoo; Kim, Ji Hye; Jang, Yeon Jin; Bae, Ji Young

    2016-01-01

    We used the job-demand-control model to answer our two research questions concerning the effects of working conditions on self-rated health and gender differences and the association between these working conditions and health among Korean manual workers. Since a disproportionate representation of women in nonstandard work positions is found in many countries, including Korea, it is important to examine how working conditions explain gender inequality in health. We used data from the 2008-2009 Korean National Health and Nutrition Examination Survey and analyzed a total sample of 1,482 men and 1,350 women using logistic regression. We found that job control was positively related to self-rated health, while both physical and mental job demands were negatively related to self-rated health. We also found significant interaction effects of job demands, control, and gender on health. Particularly, female workers' health was more vulnerable to mentally demanding job conditions. We discussed theoretical and practice implications based on these findings.

  4. Job Demand and Control Interventions: A Stakeholder-Centered Best-Evidence Synthesis of Systematic Reviews on Workplace Disability

    Directory of Open Access Journals (Sweden)

    K Williams-Whitt

    2015-04-01

    Full Text Available Background: Physical and psychological job demands in combination with the degree of control a worker has over task completion, play an important role in reducing stress. Occupational stress is an important, modifiable factor affecting work disability. However, the effectiveness of reducing job demands or increasing job control remains unclear, particularly for outcomes of interest to employers, such as absenteeism or productivity. Objective: This systematic review reports on job demand and control interventions that impact absenteeism, productivity and financial outcomes. Methods: A stakeholder-centered best-evidence synthesis was conducted with researcher and stakeholder collaboration throughout. Databases and grey literature were searched for systematic reviews between 2000 and 2012: Medline, EMBASE, the Cochrane Database of Systematic Reviews, DARE, CINAHL, PsycINFO, TRIP, health-evidence.ca, Rehab+, National Rehabilitation Information Center (NARIC, and Institute for Work and Health. Articles were assessed independently by two researchers for inclusion criteria and methodological quality. Differences were resolved through consensus. Results: The search resulted in 3363 unique titles. After review of abstracts, 115 articles were retained for full-text review. 11 articles finally met the inclusion criteria and are summarized in this synthesis. The best level of evidence we found indicates that multimodal job demand reductions for either at-work or off-work workers will reduce disability-related absenteeism. Conclusion: In general, the impacts of interventions that aim to reduce job demands or increase job control can be positive for the organization in terms of reducing absenteeism, increasing productivity and cost-effectiveness. However, more high quality research is needed to further assess the relationships and quantify effect sizes for the interventions and outcomes reviewed in this study.

  5. Job demand and control interventions: a stakeholder-centered best-evidence synthesis of systematic reviews on workplace disability.

    Science.gov (United States)

    Williams-Whitt, K; White, M I; Wagner, S L; Schultz, I Z; Koehn, C; Dionne, C E; Koehoorn, M; Harder, H; Pasca, R; Warje, O; Hsu, V; McGuire, L; Schulz, W; Kube, D; Hook, A; Wright, M D

    2015-04-01

    Physical and psychological job demands in combination with the degree of control a worker has over task completion, play an important role in reducing stress. Occupational stress is an important, modifiable factor affecting work disability. However, the effectiveness of reducing job demands or increasing job control remains unclear, particularly for outcomes of interest to employers, such as absenteeism or productivity. This systematic review reports on job demand and control interventions that impact absenteeism, productivity and financial outcomes. A stakeholder-centered best-evidence synthesis was conducted with researcher and stakeholder collaboration throughout. Databases and grey literature were searched for systematic reviews between 2000 and 2012: Medline, EMBASE, the Cochrane Database of Systematic Reviews, DARE, CINAHL, PsycINFO, TRIP, health-evidence.ca, Rehab+, National Rehabilitation Information Center (NARIC), and Institute for Work and Health. Articles were assessed independently by two researchers for inclusion criteria and methodological quality. Differences were resolved through consensus. The search resulted in 3363 unique titles. After review of abstracts, 115 articles were retained for full-text review. 11 articles finally met the inclusion criteria and are summarized in this synthesis. The best level of evidence we found indicates that multimodal job demand reductions for either at-work or off-work workers will reduce disability-related absenteeism. In general, the impacts of interventions that aim to reduce job demands or increase job control can be positive for the organization in terms of reducing absenteeism, increasing productivity and cost-effectiveness. However, more high quality research is needed to further assess the relationships and quantify effect sizes for the interventions and outcomes reviewed in this study.

  6. A novel complex air supply model for indoor air quality control via the occupant micro-environment demand ventilation

    International Nuclear Information System (INIS)

    Yang, Jie; Zhou, Bo; Jin, Maozhu; Wang, Jun; Xiong, Feng

    2016-01-01

    Protection of indoor air quality and human health can be achieved via ventilation, which has becomes one of the most important tasks for sustainable buildings. This approach also requires highly efficient and energy saving methods for modern building ventilations consisting of a set of parameters of the complex indoor system. Therefore, the advancement in understanding the characteristics of various ventilation methods is highly necessary. This study presents one novel air supply model for the complex occupant micro-environment demand control ventilations, to analyze the efficiency of various ventilation types. This model is established primarily according to the momentum and mass conservations, and goal of occupant micro-environment demand, which is a complex system with the characteristics of diversity and dynamic variation. As for different occupant densities, characteristics of outdoor air supply for controlling gaseous pollutant and three basic features of outdoor airflow supply reaching occupant micro-environment were obtained. This research shows that for various types of occupant density and storey height, the rising and descending rates of the demand outdoor airflow in mixing ventilation are higher than those under displacement ventilation conditions. In addition, since the structure is better designed and sewage flow is more efficient, the mixing ventilation also requires a much higher peak demand outdoor airflow than its counterpart. The increase of storey height will lead to a decline of pollutants in the breathing zone and the demand outdoor airflow. Fluctuations of air flow diffusion caused by the change of occupant density in architectural space, will lead to variations of outdoor airflow reaching occupant micro-environment. Accordingly, it would lead to the different peak values of demand outdoor airflow, and the difference becomes even significant if the occupant density increases. The variations of the air supply and fraction of air reaching the

  7. Optimization-based feedforward control for a drop-on-demand inkjet printer

    NARCIS (Netherlands)

    Khalate, A.; Bombois, X.; Babuska, R.; Wijshoff, H.M.A.; Waarsing, R.

    2010-01-01

    The printing quality delivered by a Drop-on-Demand (DoD) inkjet printhead is limited due to operational issues such as residual oscillations in the ink channel and the cross-talk between the ink channels. The maximal jetting frequency of a DoD inkjet printhead can be increased by quickly damping the

  8. Stability and Change in the Exposure to Demands and Control: Results of the Longitudinal SMASH Study

    NARCIS (Netherlands)

    Lange, A. de; Taris, T.; Kompier, M.; Houtman, I.L.D.; Bongers, P.M.

    2001-01-01

    In 1979 Robert Karasek introduced the job demand-contol (DC model). Through its simplicity and applicability this model has gained “substantial face value” in the theory and practice of occupational health psychology and epidemiology. According to the DC model a psychosocial work environment can be

  9. Study of Demand as Frequency Controlled Reserve in Nordic Power System

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    This paper investigates the efficacy of Demand Frequency Reserve (DFR) in Nordic power system. Heat pump, due to its switching flexibility, less disturbing impacts to customers and promising future in application, is used to represent DFR in the study. Thermodynamics of the heat pump unit...

  10. A Simulation of Rainwater Harvesting Design and Demand-Side Controls for Large Hospitals

    Directory of Open Access Journals (Sweden)

    Lawrence V. Fulton

    2018-05-01

    Full Text Available Inpatient health buildings in the United States are the most intensive users of water among large commercial buildings. Large facilities (greater than 1 million square feet consume an average of 90 million gallons per building per year. The distribution and treatment of water imposes a significant electrical power demand, which may be the single largest energy requirement for various states. Supply and demand-side solutions are needed, particularly in arid and semi-arid regions where water is scarce. This study uses continuous simulations based on 71 years of historical data to estimate how rainwater harvesting systems and demand-side interventions (e.g., low-flow devices, xeriscaping would offset the demand for externally-provided water sources in a semi-arid region. Simulations from time series models are used to generate alternative rainfall models to account for potential non-stationarity and volatility. Results demonstrate that hospital external water consumption might be reduced by approximately 25% using conservative assumptions and depending on the design of experiment parameters associated with rainfall capture area, building size, holding tank specifications, and conservation efforts.

  11. Challenges of using model predictive control for active demand side management

    DEFF Research Database (Denmark)

    Zong, Yi; You, Shi; Hu, Junjie

    2015-01-01

    When there is a high penetration of renewables in the power system, it requires coordinated management of large numbers of distributed and demand response resources, intermittent resources to maintain the grid reliability and improve operational economics. This paper presents a hierarchical...... and dynamic power price signals....

  12. The capacity investment decision for make-to-order production systems with demand rate control

    NARCIS (Netherlands)

    Bertrand, J.W.M.; Ooijen, van H.P.G.

    2012-01-01

    In this paper we study the capacity investment decision for make-to-order manufacturing firms that utilize a fixed capacity, operate in a stochastic, stationary market, and can influence their demand rate by increasing or decreasing their sales effort. We consider manufacturing situations that

  13. Customer demand prediction of service-oriented manufacturing using the least square support vector machine optimized by particle swarm optimization algorithm

    Science.gov (United States)

    Cao, Jin; Jiang, Zhibin; Wang, Kangzhou

    2017-07-01

    Many nonlinear customer satisfaction-related factors significantly influence the future customer demand for service-oriented manufacturing (SOM). To address this issue and enhance the prediction accuracy, this article develops a novel customer demand prediction approach for SOM. The approach combines the phase space reconstruction (PSR) technique with the optimized least square support vector machine (LSSVM). First, the prediction sample space is reconstructed by the PSR to enrich the time-series dynamics of the limited data sample. Then, the generalization and learning ability of the LSSVM are improved by the hybrid polynomial and radial basis function kernel. Finally, the key parameters of the LSSVM are optimized by the particle swarm optimization algorithm. In a real case study, the customer demand prediction of an air conditioner compressor is implemented. Furthermore, the effectiveness and validity of the proposed approach are demonstrated by comparison with other classical predication approaches.

  14. The effect of job demand-control-social support model on nurses' job ...

    African Journals Online (AJOL)

    Method: A cross-sectional survey was conducted from September 2014 to May 2015 in three public specialized teaching hospitals in Ethiopia. Among 1371 nurses, 360 were selected as sample. Data was collected using Job Content Questionnaire and Job Satisfaction Survey Questionnaire. After the data was collected, ...

  15. Job demand-control and job stress at work: A cross-sectional study among prison staff

    Science.gov (United States)

    Akbari, Jafar; Akbari, Rouhollah; Shakerian, Mahnaz; Mahaki, Behzad

    2017-01-01

    Introduction: Job stress can impose significant costs to the workplaces and organizations due to some issues such as absenteeism, less productivity, and medical costs. Job overload and lack of decision latitude can lead to job stress. The current study aimed to investigate the job demands and control as predictor of job stress and its relationship, with some of the demographic characteristics of Iranian prison staff. Materials and Methods: This study was performed on 171 male employees working in four prisons located in Ilam, Iran. The sampling method was census and all four prisons’ staff were selected to respond the Job Content Questionnaires. Finally, the data were analyzed using t-test or independent samples test as well as SPSS 20. Results: The highest amount of job demand (mean = 21.28) and the lowest amount of job control on average (9.76) were reported by those staff working in Darehshahr prison. There was also a significant relationship between job post and job control among the prison staff (β = −0.375, P = 0.001). Conclusion: The level of job stress reported by prison staff was high in this study mainly caused by high job demand and low job control, especially in Darehshahr prison staff. PMID:28546980

  16. Multitasking vs. multiplexing: Toward a normative account of limitations in the simultaneous execution of control-demanding behaviors

    OpenAIRE

    Feng, S. F.; Schwemmer, M.; Gershman, S. J.; Cohen, J. D.

    2014-01-01

    Why is it that behaviors that rely on control, so striking in their diversity and flexibility, are also subject to such striking limitations? Typically, people cannot engage in more than a few — and usually only a single — control-demanding task at a time. This limitation was a defining element in the earliest conceptualizations of controlled processing, it remains one of the most widely accepted axioms of cognitive psychology, and is even the basis for some laws (e.g., against the use of mob...

  17. The impact of price and tobacco control policies on the demand for electronic nicotine delivery systems.

    Science.gov (United States)

    Huang, Jidong; Tauras, John; Chaloupka, Frank J

    2014-07-01

    While much is known about the demand for conventional cigarettes, little is known about the determinants of demand for electronic nicotine delivery systems (ENDS or e-cigarettes). The goal of this study is to estimate the own and cross-price elasticity of demand for e-cigarettes and to examine the impact of cigarette prices and smoke-free policies on e-cigarette sales. Quarterly e-cigarette prices and sales and conventional cigarette prices from 2009 to 2012 were constructed from commercial retail store scanner data from 52 U.S. markets, for food, drug and mass stores, and from 25 markets, for convenience stores. Fixed-effects models were used to estimate the own and cross-price elasticity of demand for e-cigarettes and associations between e-cigarette sales and cigarette prices and smoke-free policies. Estimated own price elasticities for disposable e-cigarettes centred around -1.2, while those for reusable e-cigarettes were approximately -1.9. Disposable e-cigarette sales were higher in markets where reusable e-cigarette prices were higher and where less of the population was covered by a comprehensive smoke-free policy. There were no consistent and statistically significant relationships between cigarette prices and e-cigarette sales. E-cigarette sales are very responsive to own price changes. Disposable e-cigarettes appear to be substitutes for reusable e-cigarettes. Policies increasing e-cigarette retail prices, such as limiting rebates, discounts and coupons and imposing a tax on e-cigarettes, could potentially lead to significant reductions in e-cigarette sales. Differential tax policies based on product type could lead to substitution between different types of e-cigarettes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. The impact of price and tobacco control policies on the demand for electronic nicotine delivery systems

    Science.gov (United States)

    Huang, Jidong; Tauras, John; Chaloupka, Frank J

    2014-01-01

    Background While much is known about the demand for conventional cigarettes, little is known about the determinants of demand for electronic nicotine delivery systems (ENDS or e-cigarettes). The goal of this study is to estimate the own and cross-price elasticity of demand for e-cigarettes and to examine the impact of cigarette prices and smoke-free policies on e-cigarette sales. Methods Quarterly e-cigarette prices and sales and conventional cigarette prices from 2009 to 2012 were constructed from commercial retail store scanner data from 52 US markets, for food, drug and mass stores, and from 25 markets, for convenience stores. Fixed-effects models were used to estimate the own and cross-price elasticity of demand for e-cigarettes and associations between e-cigarette sales and cigarette prices and smoke-free policies. Results Estimated own price elasticities for disposable e-cigarettes centred around −1.2, while those for reusable e-cigarettes were approximately −1.9. Disposable e-cigarette sales were higher in markets where reusable e-cigarette prices were higher and where less of the population was covered by a comprehensive smoke-free policy. There were no consistent and statistically significant relationships between cigarette prices and e-cigarette sales. Conclusions E-cigarette sales are very responsive to own price changes. Disposable e-cigarettes appear to be substitutes for reusable e-cigarettes. Policies increasing e-cigarette retail prices, such as limiting rebates, discounts and coupons and imposing a tax on e-cigarettes, could potentially lead to significant reductions in e-cigarette sales. Differential tax policies based on product type could lead to substitution between different types of e-cigarettes. PMID:24935898

  19. Evaluating Job Demands and Control Measures for Use in Farm Worker Health Surveillance

    Science.gov (United States)

    Alterman, Toni; Gabbard, Susan; Grzywacz, Joseph G.; Shen, Rui; Li, Jia; Nakamoto, Jorge; Carroll, Daniel J.; Muntaner, Carles

    2015-01-01

    Workplace stress likely plays a role in health disparities; however, applying standard measures to studies of immigrants requires thoughtful consideration. The goal of this study was to determine the appropriateness of two measures of occupational stressors (‘decision latitude’ and ‘job demands’) for use with mostly immigrant Latino farm workers. Cross-sectional data from a pilot module containing a four-item measure of decision latitude and a two-item measure of job demands were obtained from a subsample (N = 409) of farm workers participating in the National Agricultural Workers Survey. Responses to items for both constructs were clustered toward the low end of the structured response-set. Percentages of responses of ‘very often’ and ‘always’ for each of the items were examined by educational attainment, birth country, dominant language spoken, task, and crop. Cronbach’s α, when stratified by subgroups of workers, for the decision latitude items were (0.65–0.90), but were less robust for the job demands items (0.25–0.72). The four-item decision latitude scale can be applied to occupational stress research with immigrant farm workers, and potentially other immigrant Latino worker groups. The short job demands scale requires further investigation and evaluation before suggesting widespread use. PMID:25138138

  20. Life Support Systems: Trace Contaminant and Particulate Control

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced Exploration Systems (AES) Life Support Systems project Trace Contaminant and Particulate Control task: Work in the area of trace contamination and...

  1. Stochastic control and real options valuation of thermal storage-enabled demand response from flexible district energy systems

    OpenAIRE

    Kitapbayev, Yerkin; Moriarty, John; Mancarella, Pierluigi

    2014-01-01

    In district energy systems powered by Combined Heat and Power (CHP) plants, thermal storage can significantly increase CHP flexibility to respond to real time market signals and therefore improve the business case of such demand response schemes in a Smart Grid environment. However, main challenges remain as to what is the optimal way to control inter-temporal storage operation in the presence of uncertain market prices, and then how to value the investment into storage as flexibility enabler...

  2. Job control and demands, work-life balance and wellbeing among selfemployed men and women in Europe

    OpenAIRE

    Nordenmark, Mikael; Vinberg, Stig; Strandh, Mattias

    2012-01-01

    Self-employed persons and their enterprises are regarded as important to the economy for their contribution to economic development. However, an understanding of the relationship between the psychosocial working conditions, the work-life balance and outcomes, such as health and wellbeing among the self-employed and micro-enterprise is limited. The main aim of this article is to study the relationships between control and demands at work, the work-life balance and wellbeing among self-employed...

  3. Social support, locus of control, and psychological well-being

    NARCIS (Netherlands)

    van der Zee, KI; Buunk, BP; Sanderman, R

    1997-01-01

    Social support seems to be positively related to psychological well-being. Studies have shown that individual differences exist in the ability to mobilize and use sources of support. The current study focused on locus of control as a personality factor that might be related to this ability, In 2

  4. Switched Control Strategies of Aggregated Commercial HVAC Systems for Demand Response in Smart Grids

    Directory of Open Access Journals (Sweden)

    Kai Ma

    2017-07-01

    Full Text Available This work proposes three switched control strategies for aggregated heating, ventilation, and air conditioning (HVAC systems in commercial buildings to track the automatic generation control (AGC signal in smart grid. The existing control strategies include the direct load control strategy and the setpoint regulation strategy. The direct load control strategy cannot track the AGC signal when the state of charge (SOC of the aggregated thermostatically controlled loads (TCLs exceeds their regulation capacity, while the setpoint regulation strategy provides flexible regulation capacity, but causes larger tracking errors. To improve the tracking performance, we took the advantages of the two control modes and developed three switched control strategies. The control strategies switch between the direct load control mode and the setpoint regulation mode according to different switching indices. Specifically, we design a discrete-time controller and optimize the controller parameter for the setpoint regulation strategy using the Fibonacci optimization algorithm, enabling us to propose two switched control strategies across multiple time steps. Furthermore, we extend the switched control strategies by introducing a two-stage regulation in a single time step. Simulation results demonstrate that the proposed switched control strategies can reduce the tracking errors for frequency regulation.

  5. Scheduling of Domestic Water Heater Power Demand for Maximizing PV Self-Consumption Using Model Predictive Control

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Kosek, Anna Magdalena; Martinenas, Sergejus

    2013-01-01

    This paper presents a model predictive control (MPC) strategy for maximizing photo-voltaic (PV) selfconsumption in a household context exploiting the flexible demand of an electric water heater. The predictive controller uses a water heater model and forecast of the hot Water consumption in order...... to predict the future temperature of the water and it manages its state (on and off) according to the forecasted PV production, which are computed starting from forecast of the solar irradiance. Simulations for the proof of concept and for validating the proposed control strategy are proposed. Results...... of the control approach are compared with a traditional thermostatic controller using historical measurements of a 10 kW PV installation. Economic results based on the Italian self consumption tariffs are also reported. The model of the water heater complex is a mixed grey and white box and its parameters have...

  6. Demand control on room level of the supply air temperature in an air heating and ventilation system

    DEFF Research Database (Denmark)

    Polak, Joanna; Afshari, Alireza; Bergsøe, Niels Christian

    2017-01-01

    air heating and ventilation system in a high performance single family house using BSim simulation software. The provision of the desired thermal conditions in different rooms was examined. Results show that the new control strategy can facilitate maintaining of desired temperatures in various rooms......The aim of this study was to investigate a new strategy for control of supply air temperature in an integrated air heating and ventilation system. The new strategy enables demand control of supply air temperature in individual rooms. The study is based on detailed dynamic simulations of a combined....... Moreover, this control strategy enables controlled temperature differentiation between rooms within the house and therefore provides flexibility and better balance in heat delivery. Consequently, the thermal conditions in the building can be improved....

  7. Geriatric Family Support and Diabetic Type-2 Glycemic Control

    Directory of Open Access Journals (Sweden)

    Shiva Heidari

    2008-07-01

    Full Text Available Objectives: As the most part of geriatric (65 years and older diabetic care is given at home, family support has an important role in their blood sugar level control care. This study aimed to assess the relationship between family support and blood sugar level control in such elderly suffering type-2 diabetes. Methods & Materials: Via descriptive-correlative study, one hundred fifty geriatric patients with type-2 diabetes, who referred to Institute of Endocrinology and Metabolism in Iran University of Medical Sciences were selected. Samplings based on nonrandomized and convenience. The questionnaire consisted of three sections: demographic data glucose-labeled hemoglobin (HbA1C and received-perceived family support by applying the standard questionnaire of "Diabetes Social Support-Family Version" format. Data were analyzed by SPSS version 15 by using Chi-square and Pierson Tests. Results: Results showed a significant relationship between family support and glycemic control (r=-0.56, P<0.0001. Also there were significant relationships between family support, gender and marital status (P<0.0001. There were also significant relationships between glycemic control and marital status (P=0.02, financial status (P=0.04 and educational level (P=0.05. Conclusion: Findings of this research added further evidence about the impact of family support on the health of older adults with diabetes. These findings suggest using family centered nursing interventions and collaboration of family members in care of the elderly with type-2 diabetes.

  8. Model Predictive Controller for Active Demand Side Management with PV Self-consumption in an Intelligent Building

    DEFF Research Database (Denmark)

    Zong, Yi; Mihet-Popa, Lucian; Kullmann, Daniel

    2012-01-01

    This paper presents a Model Predictive Controller (MPC) for electrical heaters’ predictive power consumption including maximizing the use of local generation (e.g. solar power) in an intelligent building. The MPC is based on dynamic power price and weather forecast, considering users’ comfort...... settings to meet an optimization objective such as minimum cost and minimum reference temperature error. It demonstrates that this MPC strategy can realize load shifting, and maximize the PV self-consumption in the residential sector. With this demand side control study, it is expected that MPC strategy...

  9. Knowledge based support for multiagent control and automation

    DEFF Research Database (Denmark)

    Saleem, Arshad; Lind, Morten

    2011-01-01

    This paper presents a mechanism for developing knowledge based support in multiagent based control and diagnosis. In particular it presents a way for autonomous agents to utilize a qualitative means-ends based model for reasoning about control situations. The proposed mechanism have been used...

  10. Experimentally supported control design for a direct drive robot

    NARCIS (Netherlands)

    Kostic, D.; Jager, de A.G.; Steinbuch, M.

    2002-01-01

    We promote the idea of an experimentally supported control design as a successful way to achieve accurate tracking of reference robot motions, under disturbance conditions and given the uncertainties arising from modeling errors. The Hinf robust control theory is used for design of motion

  11. Global developments of controls of powered roof supports

    Energy Technology Data Exchange (ETDEWEB)

    Das, S.K. [Indian School of Mines, Dhanbad (India). Centre of Longwall Mine Mechanisation

    1996-04-01

    The efficiency of hydraulic powered roof support systems mainly depends upon the efficient control and operation of hydraulic valves and their associated accessories. From 1961 to 1994 tremendous efforts had been made for the development of higher and higher efficient, reliable but simpler control systems starting from the manual hydraulic to electro-hydraulic and finally computer based electronic control system. A global survey of development of various types and design of control systems of powered roof supports has been made and many of them are highlighted in the paper for making this work a small emblem regarding the efforts of development of the controls of powered roof support systems by the global engineers of the 20th century. Many of the control systems are no longer in use and have totally vanished from this earth and many more control systems including their literatures may vanish from this world in the coming decades. This work may give a guideline regarding the selection of right type of control systems for the powered supports in future. 14 refs., 6 figs.

  12. Exposure to tobacco marketing and support for tobacco control policies.

    Science.gov (United States)

    Hammond, David; Costello, Mary-Jean; Fong, Geoffrey T; Topham, Jennifer

    2006-01-01

    To examine the salience of tobacco marketing on postsecondary campuses and student support for tobacco control policies. Face-to-face surveys were conducted with 1690 students at 3 universities in southwestern Ontario. Virtually all (97%) students reported noticing tobacco marketing in the past year, and 35% reported noticing marketing on campus. There was strong support for smoke-free restrictions on campus, including restaurants and bars (82%), and for prohibitions on campus marketing. The presence of campus policies was associated with reduced exposure to marketing and increased policy support. There is strong support among students to remove tobacco marketing from campus and to introduce comprehensive smoke-free restrictions.

  13. Automated Subsystem Control for Life Support System (ASCLSS)

    Science.gov (United States)

    Block, Roger F.

    1987-01-01

    The Automated Subsystem Control for Life Support Systems (ASCLSS) program has successfully developed and demonstrated a generic approach to the automation and control of space station subsystems. The automation system features a hierarchical and distributed real-time control architecture which places maximum controls authority at the lowest or process control level which enhances system autonomy. The ASCLSS demonstration system pioneered many automation and control concepts currently being considered in the space station data management system (DMS). Heavy emphasis is placed on controls hardware and software commonality implemented in accepted standards. The approach demonstrates successfully the application of real-time process and accountability with the subsystem or process developer. The ASCLSS system completely automates a space station subsystem (air revitalization group of the ASCLSS) which moves the crew/operator into a role of supervisory control authority. The ASCLSS program developed over 50 lessons learned which will aide future space station developers in the area of automation and controls..

  14. Self-Determination as a Moderator of Demands and Control: Implications for Employee Strain and Engagement

    Science.gov (United States)

    Parker, Stacey L.; Jimmieson, Nerina L.; Amiot, Catherine E.

    2010-01-01

    Does job control act as a stress-buffer when employees' type and level of work self-determination is taken into account? It was anticipated that job control would only be stress-buffering for employees high in self-determined and low in non-self-determined work motivation. In contrast, job control would be stress-exacerbating for employees who…

  15. Observability and Decision Support for Supervision of Distributed Power System Control

    DEFF Research Database (Denmark)

    Pertl, Michael

    approach for real-time voltage estimation in active distribution grids, and a modeling approach to harness the flexibility of an aggregation of electric vehicles. For improved monitoring and maintaining power system stability, a decision support tool for transient stability preventive control, based...... stability margin is presented. The approach delivers a near optimal solution in terms of cost minimization due to its sequential nature and shows to be robust when applied to larger power systems. The general problem of low distribution grid observability is addressed by proposing a data-driven approach...... results in additional demand for charging which will require large investments in power distribution, transmission, and generation. However, this demand is often also flexible in time and can be actively managed to reduce the required investments and to enhance power system operation. Harnessing...

  16. Control strategies and cycling demands for Li-ion storage batteries in residential micro-cogeneration systems

    International Nuclear Information System (INIS)

    Darcovich, K.; Kenney, B.; MacNeil, D.D.; Armstrong, M.M.

    2015-01-01

    Highlights: • Canadian home energy system modeled with PV, ICE CHP, battery and power grid. • Battery function is modeled on fundamental electrochemical principles. • Techno-economics of control strategies assessed. • Impact of control strategies battery cycles is developed for wear analysis. • Non-monotonic nature of battery cycles with transient renewables is discussed. - Abstract: Energy storage units have become important components in residential micro-cogeneration (MCG) systems. As MCG systems are often connected to single residences or buildings in a wide variety of settings, they are frequently unique and highly customized. Lithium-ion batteries have recently gained some profile as energy storage units of choice, because of their good capacity, high efficiency, robustness and ability to meet the demands of typical residential electrical loads. In the present work, modeled scenarios are explored which examine the performance of a MCG system with an internal combustion engine, photovoltaic input and a Li-ion storage battery. An electricity demand profile from new data collected in Ottawa, Canada is used to provide a full year energy use context for the analyses. The demands placed on the battery are examined to assess the suitability of the battery size and performance, as well as control related functionalities which reveal significantly varying battery use, and led to a quantitative expression for equivalent cycles. The energy use simulations are derived from electrochemical fundamentals adapted for a larger battery pack. Simulation output provides the basis for techno-economic commentary on how to assess large-scale Li-ion batteries for effective electrical storage purposes in MCG systems, and the impact of the nature of the control strategy on the battery service life

  17. Multitasking vs. multiplexing: Toward a normative account of limitations in the simultaneous execution of control-demanding behaviors

    Science.gov (United States)

    Feng, S. F.; Schwemmer, M.; Gershman, S. J.; Cohen, J. D.

    2014-01-01

    Why is it that behaviors that rely on control, so striking in their diversity and flexibility, are also subject to such striking limitations? Typically, people cannot engage in more than a few — and usually only a single — control-demanding task at a time. This limitation was a defining element in the earliest conceptualizations of controlled processing, it remains one of the most widely accepted axioms of cognitive psychology, and is even the basis for some laws (e.g., against the use of mobile devices while driving). Remarkably, however, the source of this limitation is still not understood. Here, we examine one potential source of this limitation, in terms of a tradeoff between the flexibility and efficiency of representation (“multiplexing”) and the simultaneous engagement of different processing pathways (“multitasking”). We show that even a modest amount of multiplexing rapidly introduces cross-talk among processing pathways, thereby constraining the number that can be productively engaged at once. We propose that, given the large number of advantages of efficient coding, the human brain has favored this over the capacity for multitasking of control-demanding processes. PMID:24481850

  18. Multitasking versus multiplexing: Toward a normative account of limitations in the simultaneous execution of control-demanding behaviors.

    Science.gov (United States)

    Feng, S F; Schwemmer, M; Gershman, S J; Cohen, J D

    2014-03-01

    Why is it that behaviors that rely on control, so striking in their diversity and flexibility, are also subject to such striking limitations? Typically, people cannot engage in more than a few-and usually only a single-control-demanding task at a time. This limitation was a defining element in the earliest conceptualizations of controlled processing; it remains one of the most widely accepted axioms of cognitive psychology, and is even the basis for some laws (e.g., against the use of mobile devices while driving). Remarkably, however, the source of this limitation is still not understood. Here, we examine one potential source of this limitation, in terms of a trade-off between the flexibility and efficiency of representation ("multiplexing") and the simultaneous engagement of different processing pathways ("multitasking"). We show that even a modest amount of multiplexing rapidly introduces cross-talk among processing pathways, thereby constraining the number that can be productively engaged at once. We propose that, given the large number of advantages of efficient coding, the human brain has favored this over the capacity for multitasking of control-demanding processes.

  19. Information and Communications Systems for Control-by-Price of Distributed Energy Resources and Flexible Demand

    DEFF Research Database (Denmark)

    Nyeng, Preben; Østergaard, Jacob

    2011-01-01

    infrastructure and subsystem design and secondly focus on the design and implementation of the end-user price-responsive controller, interfaces, and communications. The design and its applicability on existing devices is verified through laboratory tests with two cases: electric space heating thermostat control...... and a small combined heat and power unit. The results show that the price-responsive controller reduces the end user’s electricity cost, or increases his income respectively, by about 7%. At the same time, the price-responsive controller provides an interface for the transmission system operator to utilize...

  20. Fuzzy predictive filtering in nonlinear economic model predictive control for demand response

    DEFF Research Database (Denmark)

    Santos, Rui Mirra; Zong, Yi; Sousa, Joao M. C.

    2016-01-01

    problem. Moreover, to reduce the computation time and improve the controller's performance, a fuzzy predictive filter is introduced. With the purpose of testing the developed EMPC, a simulation controlling the temperature levels of an intelligent office building (PowerFlexHouse), with and without fuzzy...

  1. Age-Related Changes in Dynamic Postural Control and Attentional Demands are Minimally Affected by Local Muscle Fatigue

    Science.gov (United States)

    Remaud, Anthony; Thuong-Cong, Cécile; Bilodeau, Martin

    2016-01-01

    Normal aging results in alterations in the visual, vestibular and somtaosensory systems, which in turn modify the control of balance. Muscle fatigue may exacerbate these age-related changes in sensory and motor functions, and also increase the attentional demands associated with dynamic postural control. The purpose of this study was to investigate the effect of aging on dynamic postural control and posture-related attentional demands before and after a plantar flexor fatigue protocol. Participants (young adults: n = 15; healthy seniors: n = 13) performed a dynamic postural task along the antero-posterior (AP) and the medio-lateral (ML) axes, with and without the addition of a simple reaction time (RT) task. The dynamic postural task consisted in following a moving circle on a computer screen with the representation of the center of pressure (COP). This protocol was repeated before and after a fatigue task where ankle plantar flexor muscles were targeted. The mean COP-target distance and the mean COP velocity were calculated for each trial. Cross-correlation analyses between the COP and target displacements were also performed. RTs were recorded during dual-task trials. Results showed that while young adults adopted an anticipatory control mode to move their COP as close as possible to the target center, seniors adopted a reactive control mode, lagging behind the target center. This resulted in longer COP-target distance and higher COP velocity in the latter group. Concurrently, RT increased more in seniors when switching from static stance to dynamic postural conditions, suggesting potential alterations in the central nervous system (CNS) functions. Finally, plantar flexor muscle fatigue and dual-tasking had only minor effects on dynamic postural control of both young adults and seniors. Future studies should investigate why the fatigue-induced changes in quiet standing postural control do not seem to transfer to dynamic balance tasks. PMID:26834626

  2. Frequency-Control Reserves and Voltage Support from Electric Vehicles

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

    2013-01-01

    The increasing penetration of variable wind power generation units and electricity consumption in power systems demands additional ancillary services for its reliable operation. The battery storages of electric vehicles are one of the substitute solutions for replacing conventional fossil......-fuelled generators to supply future grid support functions. The quick start and fast response characteristics of battery storages enable the electric vehicles to provide most of the power system auxiliary tasks. This chapter discusses key ancillary services that could be supplied by electric vehicles to maintain...... the system balance in power systems with high volumes of wind power generation. To analyse the applications and performance of electric vehicles in supplying active power balancing services, the case studies simulated in wind-power-dominated Danish power systems are also presented....

  3. The glycolytic flux in Escherichia coli is controlled by the demand for ATP

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Westerhoff, H.V.; Snoep, J.L.

    2002-01-01

    additional ATP hydrolysis, we increased the flux through glycolysis to 1.7 times that of the wild-type flux. The results demonstrate why attempts in the past to increase the glycolytic flux through overexpression of glycolytic enzymes have been unsuccessful: the majority of flux control (> 75%) resides...... not inside but outside the pathway, i.e., with the enzymes that hydrolyze ATP. These data further allowed us to answer the question of whether catabolic or anabolic reactions control the growth of E. coli. We show that the majority of the control of growth rate resides in the anabolic reactions, i...

  4. Demand controlled ventilation in single-family homes; Behovstyret ventilation til enfamiliehuse

    Energy Technology Data Exchange (ETDEWEB)

    Rammer Nielsen, T.; Drivsholm, C.; Rudolph Hansen, M.P.; Kragh, J.

    2009-12-15

    This project investigated two different control strategies: A simple and cheap strategy and an advanced and expensive strategy: 1. Simple control: The ventilation rate is varied only on the whole building level giving an average ventilation rate of either 0.1 l/(s m{sup 2}) or 0.35 l/(s m{sup 2}). The air change rate is controlled by sensors in the air handling unit measuring relative humidity, temperature and CO{sub 2}. The control is based on the CO{sub 2}-concentration and absolute humidity in the supply air and exhaust air. A fixed set point for the difference in CO{sub 2}-concentration between the exhaust and supply is used to decide if the ventilation rate is low or high. As supplement to the CO{sub 2} control the difference in absolute humidity between exhaust and supply is used to assure that the ventilation remain at the high level if there is a high level of humidity in the house. 2. Advanced control: The air change rate is varied dynamically for all living rooms giving an average air change for the house between 0.1 l/(s m{sup 2}) and 0.35 l/(s m{sup 2}). The air change rate in the living rooms is controlled by CO{sub 2}-sensors in each room and dampers in the room supply duct. Relative humidity is measured in the rooms with high moisture production to ensure that the highest air exchange is activated if the relative humidity in one of these rooms is too high. Even though the two strategies have been implemented and tested for a long period of time, only the simple control can be recommended. The simple control ensures that the air quality is almost the same as if the house was ventilated constantly at the high ventilation rate. Also the simple control only requires two CO{sub 2} sensors, two relative humidity sensors and two temperature sensors in the air handling unit. These sensors should be checked from time to time e.g. when filters are exchanged. The simple control is today used in meeting rooms, office rooms and daycare facilities in a modified

  5. Expected value based fuzzy programming approach to solve integrated supplier selection and inventory control problem with fuzzy demand

    Science.gov (United States)

    Sutrisno; Widowati; Sunarsih; Kartono

    2018-01-01

    In this paper, a mathematical model in quadratic programming with fuzzy parameter is proposed to determine the optimal strategy for integrated inventory control and supplier selection problem with fuzzy demand. To solve the corresponding optimization problem, we use the expected value based fuzzy programming. Numerical examples are performed to evaluate the model. From the results, the optimal amount of each product that have to be purchased from each supplier for each time period and the optimal amount of each product that have to be stored in the inventory for each time period were determined with minimum total cost and the inventory level was sufficiently closed to the reference level.

  6. Predictive Control Applied to a Solar Desalination Plant Connected to a Greenhouse with Daily Variation of Irrigation Water Demand

    Directory of Open Access Journals (Sweden)

    Lidia Roca

    2016-03-01

    Full Text Available The water deficit in the Mediterranean area is a known matter severely affecting agriculture. One way to avoid the aquifers’ exploitation is to supply water to crops by using thermal desalination processes. Moreover, in order to guarantee long-term sustainability, the required thermal energy for the desalination process can be provided by solar energy. This paper shows simulations for a case study in which a solar multi-effect distillation plant produces water for irrigation purposes. Detailed models of the involved systems are the base of a predictive controller to operate the desalination plant and fulfil the water demanded by the crops.

  7. Computer-supported quality control in X-ray diagnosis

    International Nuclear Information System (INIS)

    Maier, W.; Klotz, E.

    1989-01-01

    Quality control of X-ray facilities in radiological departments of large hospitals is possible only if the instrumentation used for measurements is interfaced to a computer. The central computer helps to organize the measurements as well as analyse and record the results. It can also be connected to a densitometer and camera for evaluating radiographs of test devices. Other quality control tests are supported by a mobile station with equipment for non-invasive dosimetry measurements. Experience with a computer-supported system in quality control of film and film processing is described and the evaluation methods of ANSI and the German industrial standard DIN are compared. The disadvantage of these methods is the exclusion of film quality parameters, which can make processing control almost worthless. (author)

  8. Stochastic control and real options valuation of thermal storage-enabled demand response from flexible district energy systems

    International Nuclear Information System (INIS)

    Kitapbayev, Yerkin; Moriarty, John; Mancarella, Pierluigi

    2015-01-01

    Highlights: • We calculate the real option value of flexibility from CHP-thermal storage. • Stochastic optimal feedback control problem is solved under uncertain market prices. • Efficient real-time numerical solutions combine simulation, regression and recursion. • Clear, interpretable feedback control maps are produced for each hour of the day. • We give a realistic UK case study using projected market gas and electricity prices. - Abstract: In district energy systems powered by Combined Heat and Power (CHP) plants, thermal storage can significantly increase CHP flexibility to respond to real time market signals and therefore improve the business case of such demand response schemes in a Smart Grid environment. However, main challenges remain as to what is the optimal way to control inter-temporal storage operation in the presence of uncertain market prices, and then how to value the investment into storage as flexibility enabler. In this outlook, the aim of this paper is to propose a model for optimal and dynamic control and long term valuation of CHP-thermal storage in the presence of uncertain market prices. The proposed model is formulated as a stochastic control problem and numerically solved through Least Squares Monte Carlo regression analysis, with integrated investment and operational timescale analysis equivalent to real options valuation models encountered in finance. Outputs are represented by clear and interpretable feedback control strategy maps for each hour of the day, thus suitable for real time demand response under uncertainty. Numerical applications to a realistic UK case study with projected market gas and electricity prices exemplify the proposed approach and quantify the robustness of the selected storage solutions

  9. Key Residential Building Equipment Technologies for Control and Grid Support PART I (Residential)

    Energy Technology Data Exchange (ETDEWEB)

    Starke, Michael R [ORNL; Onar, Omer C [ORNL; DeVault, Robert C [ORNL

    2011-09-01

    Electrical energy consumption of the residential sector is a crucial area of research that has in the past primarily focused on increasing the efficiency of household devices such as water heaters, dishwashers, air conditioners, and clothes washer and dryer units. However, the focus of this research is shifting as objectives such as developing the smart grid and ensuring that the power system remains reliable come to the fore, along with the increasing need to reduce energy use and costs. Load research has started to focus on mechanisms to support the power system through demand reduction and/or reliability services. The power system relies on matching generation and load, and day-ahead and real-time energy markets capture most of this need. However, a separate set of grid services exist to address the discrepancies in load and generation arising from contingencies and operational mismatches, and to ensure that the transmission system is available for delivery of power from generation to load. Currently, these grid services are mostly provided by generation resources. The addition of renewable resources with their inherent variability can complicate the issue of power system reliability and lead to the increased need for grid services. Using load as a resource, through demand response programs, can fill the additional need for flexible resources and even reduce costly energy peaks. Loads have been shown to have response that is equal to or better than generation in some cases. Furthermore, price-incentivized demand response programs have been shown to reduce the peak energy requirements, thereby affecting the wholesale market efficiency and overall energy prices. The residential sector is not only the largest consumer of electrical energy in the United States, but also has the highest potential to provide demand reduction and power system support, as technological advancements in load control, sensor technologies, and communication are made. The prevailing loads

  10. Generating demand and community support for sexual and reproductive health services for young people: A review of the Literature and Programs.

    Science.gov (United States)

    Kesterton, Amy J; Cabral de Mello, Meena

    2010-09-24

    This review investigates the effectiveness of interventions aimed at generating demand for and use of sexual and reproductive health (SRH) services by young people; and interventions aimed at generating wider community support for their use. Reports and publications were found in the peer-reviewed and grey literature through academic search engines; web searches; the bibliographies of known conference proceedings and papers; and consultation with experts. The studies were reviewed against a set of inclusion criteria and those that met these were explored in more depth. The evidence-base for interventions aimed at both generating demand and community support for SRH services for young people was found under-developed and many available studies do not provide strong evidence. However, the potential of several methods to increase youth uptake has been demonstrated, this includes the linking of school education programs with youth friendly services, life skills approaches and social marketing and franchising. There is also evidence that the involvement of key community gatekeepers such as parents and religious leaders is vital to generating wider community support. In general a combined multi-component approach seems most promising with several success stories to build on. Many areas for further research have been highlighted and there is a great need for more rigorous evaluation of programmes in this area. In particular, further evaluation of individual components within a multi-component approach is needed to elucidate the most effective interventions.

  11. Generating demand and community support for sexual and reproductive health services for young people: A review of the Literature and Programs

    Directory of Open Access Journals (Sweden)

    Cabral de Mello Meena

    2010-09-01

    Full Text Available Abstract Background This review investigates the effectiveness of interventions aimed at generating demand for and use of sexual and reproductive health (SRH services by young people; and interventions aimed at generating wider community support for their use. Methods Reports and publications were found in the peer-reviewed and grey literature through academic search engines; web searches; the bibliographies of known conference proceedings and papers; and consultation with experts. The studies were reviewed against a set of inclusion criteria and those that met these were explored in more depth. Results The evidence-base for interventions aimed at both generating demand and community support for SRH services for young people was found under-developed and many available studies do not provide strong evidence. However, the potential of several methods to increase youth uptake has been demonstrated, this includes the linking of school education programs with youth friendly services, life skills approaches and social marketing and franchising. There is also evidence that the involvement of key community gatekeepers such as parents and religious leaders is vital to generating wider community support. In general a combined multi-component approach seems most promising with several success stories to build on. Conclusions Many areas for further research have been highlighted and there is a great need for more rigorous evaluation of programmes in this area. In particular, further evaluation of individual components within a multi-component approach is needed to elucidate the most effective interventions.

  12. Generating demand and community support for sexual and reproductive health services for young people: A review of the Literature and Programs

    Science.gov (United States)

    2010-01-01

    Background This review investigates the effectiveness of interventions aimed at generating demand for and use of sexual and reproductive health (SRH) services by young people; and interventions aimed at generating wider community support for their use. Methods Reports and publications were found in the peer-reviewed and grey literature through academic search engines; web searches; the bibliographies of known conference proceedings and papers; and consultation with experts. The studies were reviewed against a set of inclusion criteria and those that met these were explored in more depth. Results The evidence-base for interventions aimed at both generating demand and community support for SRH services for young people was found under-developed and many available studies do not provide strong evidence. However, the potential of several methods to increase youth uptake has been demonstrated, this includes the linking of school education programs with youth friendly services, life skills approaches and social marketing and franchising. There is also evidence that the involvement of key community gatekeepers such as parents and religious leaders is vital to generating wider community support. In general a combined multi-component approach seems most promising with several success stories to build on. Conclusions Many areas for further research have been highlighted and there is a great need for more rigorous evaluation of programmes in this area. In particular, further evaluation of individual components within a multi-component approach is needed to elucidate the most effective interventions. PMID:20863411

  13. Boiling water reactor radiation shielded Control Rod Drive Housing Supports

    Energy Technology Data Exchange (ETDEWEB)

    Baversten, B.; Linden, M.J. [ABB Combustion Engineering Nuclear Operations, Windsor, CT (United States)

    1995-03-01

    The Control Rod Drive (CRD) mechanisms are located in the area below the reactor vessel in a Boiling Water Reactor (BWR). Specifically, these CRDs are located between the bottom of the reactor vessel and above an interlocking structure of steel bars and rods, herein identified as CRD Housing Supports. The CRD Housing Supports are designed to limit the travel of a Control Rod and Control Rod Drive in the event that the CRD vessel attachement went to fail, allowing the CRD to be ejected from the vessel. By limiting the travel of the ejected CRD, the supports prevent a nuclear overpower excursion that could occur as a result of the ejected CRD. The Housing Support structure must be disassembled in order to remove CRDs for replacement or maintenance. The disassembly task can require a significant amount of outage time and personnel radiation exposure dependent on the number and location of the CRDs to be changed out. This paper presents a way to minimize personal radiation exposure through the re-design of the Housing Support structure. The following paragraphs also delineate a method of avoiding the awkward, manual, handling of the structure under the reactor vessel during a CRD change out.

  14. Two models at work : A study of interactions and specificity in relation to the Demand-Control Model and the Effort-Reward Imbalance Model

    NARCIS (Netherlands)

    Vegchel, N.

    2005-01-01

    To investigate the relation between work and employee health, several work stress models, e.g., the Demand-Control (DC) Model and the Effort-Reward Imbalance (ERI) Model, have been developed. Although these models focus on job demands and job resources, relatively little attention has been devoted

  15. Inventory control for a perishable product with non-stationary demand

    NARCIS (Netherlands)

    Pauls-Worm, K.G.J.

    2016-01-01

    Globally, around one-third of the edible parts of perishable food products is wasted every year. Adequate logistics management of the food supply chain is of importance. Inventory control of processed fresh food with a best-before or use-by date deals with the questions how much to order and how

  16. Hierarchical predictive control scheme for distributed energy storage integrated with residential demand and photovoltaic generation

    NARCIS (Netherlands)

    Lampropoulos, I.; Garoufalis, P.; van den Bosch, P.P.J.; Kling, W.L.

    2015-01-01

    A hierarchical control scheme is defined for the energy management of a battery energy storage system which is integrated in a low-voltage distribution grid with residential customers and photovoltaic installations. The scope is the economic optimisation of the integrated system by employing

  17. Systems and methods for controlling energy use during a demand limiting period

    Science.gov (United States)

    Wenzel, Michael J.; Drees, Kirk H.

    2016-04-26

    Systems and methods for limiting power consumption by a heating, ventilation, and air conditioning (HVAC) subsystem of a building are shown and described. A feedback controller is used to generate a manipulated variable based on an energy use setpoint and a measured energy use. The manipulated variable may be used for adjusting the operation of an HVAC device.

  18. Visualizing recommendations to support exploration, transparency and controllability

    NARCIS (Netherlands)

    Verbert, K.; Parra, D.; Brusilovsky, P.; Duval, E.

    2013-01-01

    Research on recommender systems has traditionally focused on the development of algorithms to improve accuracy of recommendations. So far, little research has been done to enable user interaction with such systems as a basis to support exploration and control by end users. In this paper, we present

  19. Phase Change Permeation Technology For Environmental Control Life Support Systems

    Science.gov (United States)

    Wheeler, Raymond M.

    2014-01-01

    Use of a phase change permeation membrane (Dutyion [Trademark]) to passively and selectively mobilize water in microgravity to enable improved water recovery from urine/brine for Environment Control and Life Support Systems (ECLSS) and water delivery to plans for potential use in microgravity.

  20. Supported lipid bilayers with controlled curvature via colloidal lithography

    DEFF Research Database (Denmark)

    Sundh, Maria; Manandhar, Michal; Svedhem, Sofia

    2011-01-01

    Supported lipid bilayers (SLBs) at surfaces provide a route to quantitatively study molecular interactions with and at lipid membranes via different surface-based analytical techniques. Here, a method to fabricate SLBs with controlled curvatures, in the nanometer regime over large areas, is prese...

  1. Operator support through modern optimal estimation and control

    International Nuclear Information System (INIS)

    Burdick, G.R.

    1980-01-01

    Applications of Modern Optimal Estimation and Control Theories are late in coming to the nuclear industry. Some features of the theories that might be exploited in nuclear systems applications are described. Activities at the Idaho National Engineering Laboratory relating to operator support using those theories are identified and some implementation challenges are discussed

  2. Management Control System Support of Initiatives for Disruptive Students

    Science.gov (United States)

    Scott, Colin

    2011-01-01

    Purpose: The purpose of the paper is to investigate the management control system (MCS) support of school initiatives to develop the school climate and to re-engage disruptive students. Design/methodology/approach: The paper adopts an approach of critical action research interviews with management and document reviews informed by Habermasian…

  3. Cognitive demands and the relationship between age and workload in apron control.

    Science.gov (United States)

    Müller, Andreas; Petru, Raluca; Angerer, Peter

    2011-01-01

    Apron controllers (ACs) determine the taxiways for aircraft entering the apron area until they reach their parking positions and vice versa. The aims of this study were to identify age-sensitive job requirements of apron control (Study 1), and to investigate the relationship between age of ACs and their workload (Study 2). Study 1: There were 14 experienced ACs who assessed the job requirements of apron control with the Fleishman-Job Analyses Survey. Additionally, during one shift, the number of parallel processed traffic data sets (indicating memory-load) and the number of delivered radio messages (indicating processing speed requirements) were assessed. Study 2: There were 30 ACs (age: 23-51 yr) who volunteered for trials during late shifts at an international airport. ACs assessed their subjective workload (NASA-Task Load Index) at four times during the shift and carried out an attention test (d2) before and after the shift. Moreover, their heart rate was assessed during the shift and in a reference period. Study 1: Results indicate that apron control requires especially high levels of memory-load and processing speed. Study 2: Hierarchical regression analyses revealed a u-shaped relationship between age and subjective workload (beta = 0.59) as well as heart rate (beta = 0.33). Up to the age of about 35-37 yr, workload and heart rate decreased with age, but afterwards the relationship became positive. There was no association between chronological age and attention performance. There is a need for age adequate job design in apron control that should especially aim at the reduction of memory-load and processing speed.

  4. A Decision Support Tool for Transient Stability Preventive Control

    DEFF Research Database (Denmark)

    Pertl, Michael; Weckesser, Johannes Tilman Gabriel; Rezkalla, Michel M.N.

    2017-01-01

    The paper presents a decision support tool for transient stability preventive control contributing to increased situation awareness of control room operators by providing additional information about the state of the power system in terms of transient stability. A time-domain approach is used...... a predefined minimum critical clearing time for faults at all buses is proposed, while costs are minimized. The results of the assessment are presented to the control room operator, who decides to accept the suggested dispatch or to repeat the assessment considering additional user-specific constraints...

  5. Support afferentation in the posture and locomotion control system

    Science.gov (United States)

    Grigoriev, Anatoly; Tomilovskaya, Elena; Kozlovskaya, Inesa

    Mechanisms of support afferentation contribution in posture and locomotion control, which were uncertain up to now, became the point of intensive studies recently. This became possible since the space flights era started which created the conditions for simulated microgravity experiments under conditions of dry immersion and bedrest. The results of neurophysiological studies performed under the conditions of supportlessness have shown that decline or elimination of support loads is followed by deep and fast developing alterations in postural tonic system, including development of postural muscle atonia, changes of recruitment order of motoneurons innervating the shin muscles, spinal hyperreflexia development etc. (Kozlovskaya I.B. et al., 1987). It has been also shown that application of artificial support stimulation in the regimen of natural locomotion under these conditions decreases significantly or even eliminates the development of mentioned changes. The results of these studies laid down the basis for a new hypothesis on the trigger role of support afferentation in postural tonic system and its role in organization and control of postural synergies (Grigoriev A.I. et al., 2004). According to this hypothesis the muscle reception is considered to be the leading afferent input in the control of locomotion. However the data of recent studies pointed out strongly to the participation of support afferentation in definition of cognitive strategies and motor programs of locomotor movements (Chernikova L.A. et al., 2013) and, consequently, in the processes of their initiation (Gerasimenko Yu.P. et al., 2012). The cortical locomotor reflex composes apparently the basis of these processes. The receptive field of this reflex is located in the support zones of the soles and the central part is located in the posterior parietal areas (IPL) of brain cortex. The study is supported by RFBR grant N 13-04-12091 OFI-m.

  6. An inventory model of instantaneous deteriorating items with controllable deterioration rate for time dependent demand and holding cost

    Directory of Open Access Journals (Sweden)

    Vinod Kumar Mishra

    2013-06-01

    Full Text Available Purpose: The purpose of this paper to develop an inventory model for instantaneous deteriorating items with the consideration of the facts that the deterioration rate can be controlled by using the preservation technology (PT and the holding cost & demand rate both are linear function of time which was treated as constant in most of the deteriorating inventory model. Design/methodology/approach: Developed the mathematical equation of deterministic deteriorating inventory model in which demand rate and holding cost both is linear function of time, deterioration rate is constant, backlogging rate is variable and depend on the length of the next replenishment, shortages are allowed and partially backlogged and obtain an analytical solution which optimizes the total cost of the proposed inventory model. Findings: The model can be applied for optimizing the total inventory cost of deteriorating items inventory for such business enterprises where they use the preservation technology to control the deterioration rate under other assumptions of the model. Originality/value: The inventory system for deteriorating items has been an object of study for a long time, but little is known about the effect of investing in reducing the rate of product deterioration and their significant impact in the business. The proposed model is effective as well as efficient for the business organization that uses the preservation technology to reduce the deterioration rate of the instantaneous deteriorating items of the inventory.

  7. Externally controlled on-demand release of anti-HIV drug using magneto-electric nanoparticles as carriers.

    Science.gov (United States)

    Nair, Madhavan; Guduru, Rakesh; Liang, Ping; Hong, Jeongmin; Sagar, Vidya; Khizroev, Sakhrat

    2013-01-01

    Although highly active anti-retroviral therapy has resulted in remarkable decline in the morbidity and mortality in AIDS patients, inadequately low delivery of anti-retroviral drugs across the blood-brain barrier results in virus persistence. The capability of high-efficacy-targeted drug delivery and on-demand release remains a formidable task. Here we report an in vitro study to demonstrate the on-demand release of azidothymidine 5'-triphosphate, an anti-human immunodeficiency virus drug, from 30 nm CoFe2O4@BaTiO3 magneto-electric nanoparticles by applying a low alternating current magnetic field. Magneto-electric nanoparticles as field-controlled drug carriers offer a unique capability of field-triggered release after crossing the blood-brain barrier. Owing to the intrinsic magnetoelectricity, these nanoparticles can couple external magnetic fields with the electric forces in drug-carrier bonds to enable remotely controlled delivery without exploiting heat. Functional and structural integrity of the drug after the release was confirmed in in vitro experiments with human immunodeficiency virus-infected cells and through atomic force microscopy, spectrophotometry, Fourier transform infrared and mass spectrometry studies.

  8. Effect of nitrous oxide on cisatracurium infusion demands: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Illman Hanna L

    2010-08-01

    Full Text Available Abstract Background Recent studies have questioned our previous understanding on the effect of nitrous oxide on muscle relaxants, since nitrous oxide has been shown to potentiate the action of bolus doses of mivacurium, rocuronium and vecuronium. This study was aimed to investigate the possible effect of nitrous oxide on the infusion requirements of cisatracurium. Methods 70 ASA physical status I-III patients aged 18-75 years were enrolled in this randomized trial. The patients were undergoing elective surgery requiring general anesthesia with a duration of at least 90 minutes. Patients were randomized to receive propofol and remifentanil by target controlled infusion in combination with either a mixture of oxygen and nitrous oxide (Nitrous oxide/TIVA group or oxygen in air (Air/TIVA group. A 0.1 mg/kg initial bolus of cisatracurium was administered before tracheal intubation, followed by a closed-loop computer controlled infusion of cisatracurium to produce and maintain a 90% neuromuscular block. Cumulative dose requirements of cisatracurium during the 90-min study period after bolus administration were measured and the asymptotic steady state rate of infusion to produce a constant 90% block was determined by applying nonlinear curve fitting to the data on the cumulative dose requirement during the study period. Results Controller performance, i.e. the ability of the controller to maintain neuromuscular block constant at the setpoint and patient characteristics were similar in both groups. The administration of nitrous oxide did not affect cisatracurium infusion requirements. The mean steady-state rates of infusion were 0.072 +/- 0.018 and 0.066 +/- 0.017 mg * kg-1 * h-1 in Air/TIVA and Nitrous oxide/TIVA groups, respectively. Conclusions Nitrous oxide does not affect the infusion requirements of cisatracurium. Trial registration ClinicalTrials.gov NCT01152905; European Clinical Trials Database at http://eudract.emea.eu.int/2006-006037-41.

  9. Pupillary Response as an Indicator of Processing Demands Within a Supervisory Control Simulation Environment

    Science.gov (United States)

    2015-05-07

    Yerkes, R.M., and Dodson, J.D. (1908). The relation of strength of stimulus to rapidity of habit -formation. Journal of comparative neurology and psychology 18, 459-482. ...the amount of mental effort exerted (Kahneman, 1973; Beatty & Lucero-Wagoner, 2000; Andreassi, 2007). The vast majority of these studies , however...of this initial study , the authors were interested in investigating whether pupillometry data collected in a realistic UAV supervisory control

  10. ERP System Audit a Control Support For Knowledge Management

    Directory of Open Access Journals (Sweden)

    Traian SURCEL

    2008-01-01

    Full Text Available The ERP system supports most of the business system that maintains in a single database the data needed for a variety of business functions such as Manufacturing, SCM, Financials, Projects, Human Resources and CRM; the audit of this systems is necessary in order to give reasonable assurance to the company on its core system. Obtained evidence evaluation can ensure whether the organization's IT&C system safeguard assets, maintains data integrity, and is operating effectively and efficiently to achieve the organization's goals or objectives. The audit process respecting the methodology based on: gathering information and plan; obtaining an understanding of internal controls; performing test of controls and substantive tests, develop a control support on quality of flow of information and knowledge from formal perspective, for Knowledge Management in large enterprises.

  11. The Challenges of the "Software Support for Industrial Controls" Contract

    CERN Document Server

    Ninin, P

    2000-01-01

    ST division is currently specifying a 'Software Support for Industrial Controls' contract. The application of this contract and its success will require several changes in our habits for specifying, designing, and maintaining control systems. This paper summarizes some key concepts which should be respected in order to obtain maximum benefits from the future contract and to optimize the software activities in the division. The contract concerns the maintenance and development of the monitoring and control systems used for supervising CERN's technical infrastructure (electrical distribution, cooling water, air conditioning, safety, and access control). The systems concerned consist of computer and communication hardware and software, tailored to provide specific functionalities for the remote operation, command, and monitoring of equipment. All these systems use commercially available software and hardware such as SCADA, PLCs and associated drivers, controllers, fieldbuses, and networks. It is intended to cont...

  12. Estresse ocupacional e saúde: contribuições do Modelo Demanda-Controle Occupational stress and health: contributions of the Demand-Control Model

    Directory of Open Access Journals (Sweden)

    Tânia Maria de Araújo

    2003-01-01

    Full Text Available Nos últimos anos registra-se marcado esforço de construção de modelos teórico-metodológicos para avaliar características do trabalho e efeitos à saúde dos trabalhadores. Dentre os modelos propostos, o Modelo Demanda-Controle tem alcançado destaque. Esse modelo recorta duas dimensões no ambiente laboral: as demandas psicológicas e o controle do trabalhador sobre o próprio trabalho. O Job Content Questionnaire (JCQ é o instrumento proposto para medir essas dimensões do trabalho. Este estudo objetiva apresentar as bases teóricas e metodológicas do modelo demanda-controle, e discutir sua capacidade para identificar diferentes situações de trabalho no contexto brasileiro, a partir do uso do JCQ. Achados preliminares de dois estudos epidemiológicos, de corte transversal, são apresentados e discutidos. Os estudos avaliaram aspectos psicossociais do trabalho, utilizando o JCQ, e a saúde mental dos trabalhadores, usando o SRQ-20. Os resultados apontaram boa capacidade do modelo demanda-controle para identificar diferentes situações de risco à saúde mental dos trabalhadores. Aspectos relacionados à demanda psicológica do trabalho estavam mais fortemente associados a elevadas prevalências de distúrbios psíquicos menores do que os aspectos referentes ao controle.In the last years, strong efforts have been made to construct theoretical and methodological models that evaluate work characteristics and health effects in occupational groups. Among the proposed models, the Demand-Control Model has had a worldwide use. This model identifies two job dimensions in the work situation: psychological job demand and job control. The Job Content Questionnaire (JCQ has been proposed as an instrument for measuring these work dimensions. This study aim to present the theoretical and methodological bases of the Demand-Control Model and to discuss this model capability to identify different work situations in the Brazilian context, using the JCQ

  13. Exact Fill Rates for the (R, S Inventory Control with Discrete Distributed Demands for the Backordering Case

    Directory of Open Access Journals (Sweden)

    Eugenia BABILONI

    2012-01-01

    Full Text Available The fill rate is usually computed by using the traditional approach, which calculates it as the complement of the quotient between the expected unfulfilled demand and the expected demand per replenishment cycle, instead of directly the expected fraction of fulfilled demand. Furthermore the available methods to estimate the fill rate apply only under specific demand conditions. This paper shows the research gap regarding the estimation procedures to compute the fill rate and suggests: (i a new exact procedure to compute the traditional approximation for any discrete demand distribution; and (ii a new method to compute the fill rate directly as the fraction of fulfilled demand for any discrete demand distribution. Simulation results show that the latter methods outperform the traditional approach, which underestimates the simulated fill rate, over different demand patterns. This paper focuses on the traditional periodic review, base stock system when backlogged demands are allowed.

  14. Demand Uncertainty

    DEFF Research Database (Denmark)

    Nguyen, Daniel Xuyen

    This paper presents a model of trade that explains why firms wait to export and why many exporters fail. Firms face uncertain demands that are only realized after the firm enters the destination. The model retools the timing of uncertainty resolution found in productivity heterogeneity models....... This retooling addresses several shortcomings. First, the imperfect correlation of demands reconciles the sales variation observed in and across destinations. Second, since demands for the firm's output are correlated across destinations, a firm can use previously realized demands to forecast unknown demands...... in untested destinations. The option to forecast demands causes firms to delay exporting in order to gather more information about foreign demand. Third, since uncertainty is resolved after entry, many firms enter a destination and then exit after learning that they cannot profit. This prediction reconciles...

  15. Experimental Determination of Demand Response Control Models and Cost of Control for Ensembles of Window-Mount Air Conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Drew Adam [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-29

    Control of consumer electrical devices for providing electrical grid services is expanding in both the scope and the diversity of loads that are engaged in control, but there are few experimentally-based models of these devices suitable for control designs and for assessing the cost of control. A laboratory-scale test system is developed to experimentally evaluate the use of a simple window-mount air conditioner for electrical grid regulation services. The experimental test bed is a single, isolated air conditioner embedded in a test system that both emulates the thermodynamics of an air conditioned room and also isolates the air conditioner from the real-world external environmental and human variables that perturb the careful measurements required to capture a model that fully characterizes both the control response functions and the cost of control. The control response functions and cost of control are measured using harmonic perturbation of the temperature set point and a test protocol that further isolates the air conditioner from low frequency environmental variability.

  16. DC Control Effort Minimized for Magnetic-Bearing-Supported Shaft

    Science.gov (United States)

    Brown, Gerald V.

    2001-01-01

    A magnetic-bearing-supported shaft may have a number of concentricity and alignment problems. One of these involves the relationship of the position sensors, the centerline of the backup bearings, and the magnetic center of the magnetic bearings. For magnetic bearings with permanent magnet biasing, the average control current for a given control axis that is not bearing the shaft weight will be minimized if the shaft is centered, on average over a revolution, at the magnetic center of the bearings. That position may not yield zero sensor output or center the shaft in the backup bearing clearance. The desired shaft position that gives zero average current can be achieved if a simple additional term is added to the control law. Suppose that the instantaneous control currents from each bearing are available from measurements and can be input into the control computer. If each control current is integrated with a very small rate of accumulation and the result is added to the control output, the shaft will gradually move to a position where the control current averages to zero over many revolutions. This will occur regardless of any offsets of the position sensor inputs. At that position, the average control effort is minimized in comparison to other possible locations of the shaft. Nonlinearities of the magnetic bearing are minimized at that location as well.

  17. A Control Room Design Support system using virtual reality

    International Nuclear Information System (INIS)

    Sakuma, Akira; Fukumoto, Akira; Hatanaka, Takahiro; Saijou, Nobuyuki; Masugi, Tsuyoshi

    1999-01-01

    To enhance the efficiency of design and evaluation of the control and monitoring system in the main control room of nuclear power plants, we have been developing a COntrol Room Design Support system (CORDS) using virtual reality technology. Using CORDS, vendor designers and customers can visually check and review human interface design of the proposed control and monitoring systems. The geometry of panels and consoles of the control and monitoring system represented as 3-dimensional static CG (computer graphics) models. Dynamic components, such as control switches, CRT displays and so on, are modeled as dynamic objects in the geometric CG model environment. CORDS is linked with real-time plant simulator. The dynamic objects respond to the corresponding process variables in the simulator, which enables visual evaluation of the response of the control and monitoring system for the various normal and abnormal plant status. The behavior of plant operators can be simulated in 3-dimensional CG control room environment. The operators can be displayed as CG figures and their motions are modeled and controlled based on plant operation manuals. A prototype of CORDS has constructed on a graphics workstation and two engineering workstations. (author)

  18. Being active supports client control over health care.

    Science.gov (United States)

    Fiveash, Barb; Nay, Rhonda

    2004-10-01

    The purpose of this study was to identify how healthcare clients achieve and maintain a sense of control over their health. The literature review conducted refers to: (i) key definitions of control, (ii) locus of control, and (iii) control and wellbeing. Participants with a range of acute and chronic health conditions and who had been hospitalised at some point were selected for the study. Symbolic interactionism (Blumer, 1969) and modified grounded theory of Strauss & Corbin (1998) provided the frameworks for this study. During the six month study period, data were collected from sixty participants and included interviews, participant observation, reviewing participants' records (nursing care plans, nursing notes and case histories), the nursing units' philosophy, organisational charts, policies and procedures, annual reports, consumer brochures and any other relevant information sources. Findings from the study indicated that participants moved from feeling vulnerable to having a sense of control through to being purposefully active. Vulnerability was associated with: (i) having limited choices in respect to their health, (ii) lacking adequate health information to make choices, (iii) being ignored by health providers with respect to their needs, and (iv) lacking friend/family supports. Purposefully activating was associated with three major categories: (i) reflecting, (ii) being self-determiningly involved and (iii) normalising. Findings from this study could be used by health care clients who want a sense of control over their health care, and also by health care providers who wish to support clients in the healthcare process.

  19. Induced abortion on demand and birth rate in Sami-speaking municipalities and a control group in Finnmark, Norway

    Directory of Open Access Journals (Sweden)

    Jan Norum

    2013-05-01

    Full Text Available Objectives. The objective of this study was to analyze the birth and induced abortion on demand (IAD rate among women in Sami-speaking communities and a control group in Finnmark County, Norway. Methods. The 6 northern municipalities included in the administration area of the Sami language law (study group were matched with a control group of 9 municipalities. Population data (numbers, sex and age were accessed from Statistics Norway. Data on birth rate and IAD during the time period 1999–2009 were derived from the Medical Birth Registry (MBR of Norway. Data on number of women in fertile age (15–44 years were obtained from Statistics Norway. Between 2001 and 2008, this age group was reduced by 12% (Sami and 23% (controls, respectively. Results. Finnmark County has a high IAD rate and 1 in 4 pregnancies (spontaneous abortions excluded ended in IAD in the study and control groups. The total fertility rate per woman was 1.94 and 1.87 births, respectively. There was no difference between groups with regard to the IAD/birth ratio (P=0.94 or general fertility rate GFR (P=0.82. Conclusions. Women in the Sami-majority area and a control group in Finnmark County experienced a similar frequency of IAD and fertility rate.

  20. System Design for Demand Controlled Ventilation in Multi-Family Dwellings

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Nielsen, Toke Rammer

    2011-01-01

    This paper presents an investigation into solutions for the system design of a centralized DCV system in multi-family dwellings. The design focused on simple and inexpensive solutions. A cost benefit estimate showed that the initial cost of implementing DCV in a system with an efficient heat...... exchanger should not exceed 3400 DKK per dwelling in regions with weather conditions similar to the Danish climate. A design expected to fulfil this requirement was investigated in detail with regard to its electricity consumption by evaluation of different control strategies. Systems with variable airflows...... load reduces throttling and energy can be saved. A static pressure reset strategy was applied to a dwelling-specific DCV system where the airflow varied between three fixed rates. The system performance was evaluated for two diffusers. The annual electricity consumption was reduced by 20% to 30% when...

  1. Alloy chemistry and microstructural control to meet the demands of the automotive Stirling engine

    Science.gov (United States)

    Stephens, J. R.

    1986-01-01

    The automotive Stirling engine now under development by DOE/NASA as an alternative to the internal combustion engine, imposes severe materials requirements for the hot portion of the engine. Materials selected must be low cost and contain a minimum of strategic elements so that availability is not a problem. Heater head tubes contain high pressure hydrogen on the inside and are exposed to hot combustion gases on the outside surface. The cylinders and regenerator housings must be readily castable into complex shapes having varying wall thicknesses and be amenable to brazing and welding operations. Also, high strength, oxidation resistance, resistance to hydrogen permeation, cyclic operation, and long-life are required. A research program conducted by NASA Lewis focused on alloy chemistry and microstructural control to achieve the desired properties over the life of the engine. Results of alloy selection, characterization, evaluation, and actual engine testing of selected materials are presented.

  2. Application of stakeholder-based and modelling approaches for supporting robust adaptation decision making under future climatic uncertainty and changing urban-agricultural water demand

    Science.gov (United States)

    Bhave, Ajay; Dessai, Suraje; Conway, Declan; Stainforth, David

    2016-04-01

    agricultural water demand significantly affect downstream water availability. Water demand options demonstrate potential to improve environmental flow conditions and satisfy legal water supply requirements for downstream riparian states. On the other hand, currently planned large scale infrastructural projects demonstrate reduced value in certain scenarios, illustrating the impacts of lock-in effects of large scale infrastructure. From a methodological perspective, we find that while the stakeholder-driven approach revealed robust options in a resource-light manner and helped initiate much needed interaction amongst stakeholders, the modelling approach provides complementary quantitative information. The study reveals robust adaptation options for this important basin and provides a strong methodological basis for carrying out future studies that support adaptation decision making.

  3. An Efficient Demand Side Management System with a New Optimized Home Energy Management Controller in Smart Grid

    Directory of Open Access Journals (Sweden)

    Hafiz Majid Hussain

    2018-01-01

    Full Text Available The traditional power grid is inadequate to overcome modern day challenges. As the modern era demands the traditional power grid to be more reliable, resilient, and cost-effective, the concept of smart grid evolves and various methods have been developed to overcome these demands which make the smart grid superior over the traditional power grid. One of the essential components of the smart grid, home energy management system (HEMS enhances the energy efficiency of electricity infrastructure in a residential area. In this aspect, we propose an efficient home energy management controller (EHEMC based on genetic harmony search algorithm (GHSA to reduce electricity expense, peak to average ratio (PAR, and maximize user comfort. We consider EHEMC for a single home and multiple homes with real-time electricity pricing (RTEP and critical peak pricing (CPP tariffs. In particular, for multiple homes, we classify modes of operation for the appliances according to their energy consumption with varying operation time slots. The constrained optimization problem is solved using heuristic algorithms: wind-driven optimization (WDO, harmony search algorithm (HSA, genetic algorithm (GA, and proposed algorithm GHSA. The proposed algorithm GHSA shows higher search efficiency and dynamic capability to attain optimal solutions as compared to existing algorithms. Simulation results also show that the proposed algorithm GHSA outperforms the existing algorithms in terms of reduction in electricity cost, PAR, and maximize user comfort.

  4. Representational Similarity Analysis Reveals Heterogeneous Networks Supporting Speech Motor Control

    DEFF Research Database (Denmark)

    Zheng, Zane; Cusack, Rhodri; Johnsrude, Ingrid

    The everyday act of speaking involves the complex processes of speech motor control. One important feature of such control is regulation of articulation when auditory concomitants of speech do not correspond to the intended motor gesture. While theoretical accounts of speech monitoring posit...... multiple functional components required for detection of errors in speech planning (e.g., Levelt, 1983), neuroimaging studies generally indicate either single brain regions sensitive to speech production errors, or small, discrete networks. Here we demonstrate that the complex system controlling speech...... is supported by a complex neural network that is involved in linguistic, motoric and sensory processing. With the aid of novel real-time acoustic analyses and representational similarity analyses of fMRI signals, our data show functionally differentiated networks underlying auditory feedback control of speech....

  5. System Engineering and Integration of Controls for Advanced Life Support

    Science.gov (United States)

    Overland, David; Hoo, Karlene; Ciskowski, Marvin

    2006-01-01

    The Advanced Integration Matrix (AIM) project at the Johnson Space Center (JSC) was chartered to study and solve systems-level integration issues for exploration missions. One of the first issues identified was an inability to conduct trade studies on control system architectures due to the absence of mature evaluation criteria. Such architectures are necessary to enable integration of regenerative life support systems. A team was formed to address issues concerning software and hardware architectures and system controls.. The team has investigated what is required to integrate controls for the types of non-linear dynamic systems encountered in advanced life support. To this end, a water processing bioreactor testbed is being developed which will enable prototyping and testing of integration strategies and technologies. Although systems such as the water bioreactors exhibit the complexities of interactions between control schemes most vividly, it is apparent that this behavior and its attendant risks will manifest itself among any set of interdependent autonomous control systems. A methodology for developing integration requirements for interdependent and autonomous systems is a goal of this team and this testbed. This paper is a high-level summary of the current status of the investigation, the issues encountered, some tentative conclusions, and the direction expected for further research.

  6. Project Orion, Environmental Control and Life Support System Integrated Studies

    Science.gov (United States)

    Russell, James F.; Lewis, John F.

    2008-01-01

    Orion is the next vehicle for human space travel. Humans will be sustained in space by the Orion subystem, environmental control and life support (ECLS). The ECLS concept at the subsystem level is outlined by function and technology. In the past two years, the interface definition with other subsystems has increased through different integrated studies. The paper presents the key requirements and discusses three recent studies (e.g., unpressurized cargo) along with the respective impacts on the ECLS design moving forward.

  7. Controlled Ecological Life Support System Breadboard Project - 1988

    Science.gov (United States)

    Knott, W. M.

    1989-01-01

    The Controlled Ecological Life Support System (CELSS) Breadboard Project, NASA's effort to develop the technology required to produce a functioning bioregenerative system, is discussed. The different phases of the project and its current status are described. The relationship between the project components are shown, and major project activities for fiscal years 1989-1993 are listed. The biomass production chamber to be used by the project is described.

  8. Exact Fill Rates for the (R, S) Inventory Control with Discrete Distributed Demands for the Backordering Case

    OpenAIRE

    Eugenia BABILONI; Ester GUIJARRO; Manuel CARDÓS; Sofía ESTELLÉS

    2012-01-01

    The fill rate is usually computed by using the traditional approach, which calculates it as the complement of the quotient between the expected unfulfilled demand and the expected demand per replenishment cycle, instead of directly the expected fraction of fulfilled demand. Furthermore the available methods to estimate the fill rate apply only under specific demand conditions. This paper shows the research gap regarding the estimation procedures to compute the fill rate and suggests: (i) a ne...

  9. Experimental analysis of flexibility change with different levels of power reduction by demand response activation on thermostat controlled loads

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Hu, Junjie

    2017-01-01

    This paper studies the flexibility available with thermostatically controlled loads (TCLs) to provide power system services by demand response (DR) activation. Although the DR activation on TCLs can provide power system ancillary services, it is important to know how long such services can...... be provided for when different levels of power reduction are imposed. The flexibility change with different levels of power reduction is tested experimentally with domestic fridges used by real customers with unknown user interaction. The investigation quantifies the flexibility of household fridges...... and the impact of DR activation in terms of deviation in the average temperature. The maximum possible power reduction with the cluster of refrigerators is 67% and the available flexibility with the cluster of refrigerators is 10%. The resulting deviation in the average temperature is 14%....

  10. The demand-control model for job strain: a commentary on different ways to operationalize the exposure variable

    Directory of Open Access Journals (Sweden)

    Márcia Guimarães de Mello Alves

    2015-01-01

    Full Text Available Demand-control has been the most widely used model to study job strain in various countries. However, researchers have used the model differently, thus hindering the comparison of results. Such heterogeneity appears in both the study instrument used and in the definition of the main exposure variable - high strain. This cross-sectional study aimed to assess differences between various ways of operationalizing job strain through association with prevalent hypertension in a cohort of workers (Pro-Health Study. No difference in the association between high job strain and hypertension was found according to the different ways of operationalizing exposure, even though prevalence varied widely, according to the adopted form, from 19.6% for quadrants to 42% for subtraction tertile. The authors recommend further studies to define the cutoff for exposure variables using combined subjective and objective data.

  11. Optimal Ordering Policy and Coordination Mechanism of a Supply Chain with Controllable Lead-Time-Dependent Demand Forecast

    Directory of Open Access Journals (Sweden)

    Hua-Ming Song

    2011-01-01

    Full Text Available This paper investigates the ordering decisions and coordination mechanism for a distributed short-life-cycle supply chain. The objective is to maximize the whole supply chain's expected profit and meanwhile make the supply chain participants achieve a Pareto improvement. We treat lead time as a controllable variable, thus the demand forecast is dependent on lead time: the shorter lead time, the better forecast. Moreover, optimal decision-making models for lead time and order quantity are formulated and compared in the decentralized and centralized cases. Besides, a three-parameter contract is proposed to coordinate the supply chain and alleviate the double margin in the decentralized scenario. In addition, based on the analysis of the models, we develop an algorithmic procedure to find the optimal ordering decisions. Finally, a numerical example is also presented to illustrate the results.

  12. Application of particle swarm optimisation for solving deteriorating inventory model with fluctuating demand and controllable deterioration rate

    Science.gov (United States)

    Chen, Yu-Ren; Dye, Chung-Yuan

    2013-06-01

    In most of the inventory models in the literature, the deterioration rate of goods is viewed as an exogenous variable, which is not subject to control. In the real market, the retailer can reduce the deterioration rate of product by making effective capital investment in storehouse equipments. In this study, we formulate a deteriorating inventory model with time-varying demand by allowing preservation technology cost as a decision variable in conjunction with replacement policy. The objective is to find the optimal replenishment and preservation technology investment strategies while minimising the total cost over the planning horizon. For any given feasible replenishment scheme, we first prove that the optimal preservation technology investment strategy not only exists but is also unique. Then, a particle swarm optimisation is coded and used to solve the nonlinear programming problem by employing the properties derived from this article. Some numerical examples are used to illustrate the features of the proposed model.

  13. Is the mineralisation response to root exudation controlled by the microbial stoichiometric demand in subarctic soils?

    Science.gov (United States)

    Rousk, Johannes; Hicks, Lettice; Leizeaga, Ainara; Michelsen, Anders; Rousk, Kathrin

    2017-04-01

    Climate change will expose arctic and subarctic systems to warming and a shift towards plant communities with more rhizosphere labile C input. Labile C can also increase the rate of loss of native soil organic matter (SOM); a phenomenon termed 'priming'. We investigated how warming (+1.1˚ C over ambient using open top chambers) and the addition of plant litter (90 g m-2 y-1) or organic nitrogen (N) (fungal fruit bodies; 90 g m-2 y-1) in the Subarctic influenced the susceptibility of SOM mineralisation to priming, and its microbial underpinnings. Root exudation were simulated with the addition of labile organic matter both in the form of only labile C (13C-glucose) or in the form of labile C and N (13C-alanine). We hypothesized that labile C would induce a higher mineralization of N than C sourced from SOM ("N mining"); a response unrelated to microbial growth responses. We also hypothesized that the N mining effect would be more pronounced in climate change simulation treatments of higher C/N (plant litter) than treatments with lower C/N (fungal fruitbodies and warming), with the control treatments intermediate. We also hypothesized that the addition of labile C and N would not result in selective N mining, but instead coupled responses of C and N mineralisation sourced from SOM; a response that would coincide with stimulated microbial growth responses. Labile C appeared to inhibit the mineralisation of C from SOM by up to 60% within hours. In contrast, the mineralisation of N from SOM was stimulated by up to 300%. These responses occurred rapidly and were unrelated to microbial successional dynamics, suggesting catabolic responses. Considered separately, the labile-C inhibited C mineralisation is compatible with previously reported findings termed 'preferential substrate utilisation' or 'negative apparent priming', while the stimulated N mineralisation responses echo recent reports of 'real priming' of SOM mineralisation. However, C and N mineralisation responses

  14. Instrumentation and control activities at the Electric Power Research Institute to support operator support systems

    International Nuclear Information System (INIS)

    Naser, J.

    1995-01-01

    Most nuclear power plants in the United States continue to operate with analog instrumentation and control (I and C) technology designed 20 to 40 years ago. This equipment is approaching or exceeding its life expectancy, resulting in increasing maintenance efforts to sustain system performance. Decreasing availability of replacement parts and the accelerating deterioration of the infrastructure of manufacturers that support analog technology exacerbate obsolescence problems and resultant operation and maintenance (O and M) cost increases. Modern digital technology holds a significant potential to improve the safety, cost-effectiveness, productivity, and, therefore, competitiveness of nuclear power plants. Operator support systems provide the tools to help achieve this potential. Reliable, integrated information is a critical element for protecting the utility's capital investment and increasing availability, reliability, and productivity. Integrated operator support systems with integrated information can perform more effectively to increase productivity, to enhance safety, and to reduce O and M costs. The plant communications and computing architecture is the infrastructure needed to allow the implementation of I and C systems and associated operator support systems in an integrated manner. Current technology for distributed digital systems, plant process computers, and plant communications and computing networks support the integration of systems and information. (author). 16 refs

  15. The support of autonomy and the control of behavior.

    Science.gov (United States)

    Deci, E L; Ryan, R M

    1987-12-01

    In this article we suggest that events and contexts relevant to the initiation and regulation of intentional behavior can function either to support autonomy (i.e., to promote choice) or to control behavior (i.e., to pressure one toward specific outcomes). Research herein reviewed indicates that this distinction is relevant to specific external events and to general interpersonal contexts as well as to specific internal events and to general personality orientations. That is, the distinction is relevant whether one's analysis focuses on social psychological variables or on personality variables. The research review details those contextual and person factors that tend to promote autonomy and those that tend to control. Furthermore, it shows that autonomy support has generally been associated with more intrinsic motivation, greater interest, less pressure and tension, more creativity, more cognitive flexibility, better conceptual learning, a more positive emotional tone, higher self-esteem, more trust, greater persistence of behavior change, and better physical and psychological health than has control. Also, these results have converged across different assessment procedures, different research methods, and different subject populations. On the basis of these results, we present an organismic perspective in which we argue that the regulation of intentional behavior varies along a continuum from autonomous (i.e., self-determined) to controlled. The relation of this organismic perspective to historical developments in empirical psychology is discussed, with a particular emphasis on its implications for the study of social psychology and personality.

  16. Decentralized control of units in smart grids for the support of renewable energy supply

    Energy Technology Data Exchange (ETDEWEB)

    Sonnenschein, Michael, E-mail: Michael.Sonnenschein@Uni-Oldenburg.DE [University of Oldenburg, Department of Computing Science, D-26111 Oldenburg (Germany); Lünsdorf, Ontje, E-mail: Ontje.Luensdorf@OFFIS.DE [OFFIS Institute for Information Technology, Escherweg 2, D-26121 Oldenburg (Germany); Bremer, Jörg, E-mail: Joerg.Bremer@Uni-Oldenburg.DE [University of Oldenburg, Department of Computing Science, D-26111 Oldenburg (Germany); Tröschel, Martin, E-mail: Martin.Troeschel@OFFIS.DE [OFFIS Institute for Information Technology, Escherweg 2, D-26121 Oldenburg (Germany)

    2015-04-15

    Due to the significant environmental impact of power production from fossil fuels and nuclear fission, future energy systems will increasingly rely on distributed and renewable energy sources (RES). The electrical feed-in from photovoltaic (PV) systems and wind energy converters (WEC) varies greatly both over short and long time periods (from minutes to seasons), and (not only) by this effect the supply of electrical power from RES and the demand for electrical power are not per se matching. In addition, with a growing share of generation capacity especially in distribution grids, the top-down paradigm of electricity distribution is gradually replaced by a bottom-up power supply. This altogether leads to new problems regarding the safe and reliable operation of power grids. In order to address these challenges, the notion of Smart Grids has been introduced. The inherent flexibilities, i.e. the set of feasible power schedules, of distributed power units have to be controlled in order to support demand–supply matching as well as stable grid operation. Controllable power units are e.g. combined heat and power plants, power storage systems such as batteries, and flexible power consumers such as heat pumps. By controlling the flexibilities of these units we are particularly able to optimize the local utilization of RES feed-in in a given power grid by integrating both supply and demand management measures with special respect to the electrical infrastructure. In this context, decentralized systems, autonomous agents and the concept of self-organizing systems will become key elements of the ICT based control of power units. In this contribution, we first show how a decentralized load management system for battery charging/discharging of electrical vehicles (EVs) can increase the locally used share of supply from PV systems in a low voltage grid. For a reliable demand side management of large sets of appliances, dynamic clustering of these appliances into uniformly

  17. Decentralized control of units in smart grids for the support of renewable energy supply

    International Nuclear Information System (INIS)

    Sonnenschein, Michael; Lünsdorf, Ontje; Bremer, Jörg; Tröschel, Martin

    2015-01-01

    Due to the significant environmental impact of power production from fossil fuels and nuclear fission, future energy systems will increasingly rely on distributed and renewable energy sources (RES). The electrical feed-in from photovoltaic (PV) systems and wind energy converters (WEC) varies greatly both over short and long time periods (from minutes to seasons), and (not only) by this effect the supply of electrical power from RES and the demand for electrical power are not per se matching. In addition, with a growing share of generation capacity especially in distribution grids, the top-down paradigm of electricity distribution is gradually replaced by a bottom-up power supply. This altogether leads to new problems regarding the safe and reliable operation of power grids. In order to address these challenges, the notion of Smart Grids has been introduced. The inherent flexibilities, i.e. the set of feasible power schedules, of distributed power units have to be controlled in order to support demand–supply matching as well as stable grid operation. Controllable power units are e.g. combined heat and power plants, power storage systems such as batteries, and flexible power consumers such as heat pumps. By controlling the flexibilities of these units we are particularly able to optimize the local utilization of RES feed-in in a given power grid by integrating both supply and demand management measures with special respect to the electrical infrastructure. In this context, decentralized systems, autonomous agents and the concept of self-organizing systems will become key elements of the ICT based control of power units. In this contribution, we first show how a decentralized load management system for battery charging/discharging of electrical vehicles (EVs) can increase the locally used share of supply from PV systems in a low voltage grid. For a reliable demand side management of large sets of appliances, dynamic clustering of these appliances into uniformly

  18. Permissiveness toward tobacco sponsorship undermines tobacco control support in Africa.

    Science.gov (United States)

    Ayo-Yusuf, Olalekan A; Olutola, Bukola G; Agaku, Israel T

    2016-06-01

    School personnel, who are respected members of the community, may exert significant influence on policy adoption. This study assessed the impact of school personnel's permissiveness toward tobacco industry sponsorship activities on their support for complete bans on tobacco advertisements, comprehensive smoke-free laws and increased tobacco prices. Representative data were obtained from the Global School Personnel Survey for 29 African countries (n = 17 929). Adjusted prevalence ratios (aPR) were calculated using multi-variable Poisson regression models to assess the impact of permissiveness toward tobacco sponsorship activities on support for tobacco control policies (p industry should be allowed to sponsor school events were significantly less likely to support complete bans on tobacco advertisements [aPR = 0.89; 95% confidence interval (CI) 0.84-0.95] and comprehensive smoke-free laws (aPR = 0.95; 95% CI 0.92-0.98). In contrast, support for complete tobacco advertisement bans was more likely among those who believed that the tobacco industry encourages youths to smoke (aPR = 1.27; 95% CI 1.17-1.37), and among those who taught about health sometimes (aPR = 1.06; 95% CI 1.01-1.11) or a lot (aPR = 1.05; 95% CI 1.01-1.10) compared with those who did not teach about health at all. These findings underscore the need to educate school personnel on tobacco industry's strategies to undermine tobacco control policies. This may help to build school personnel support for laws intended to reduce youth susceptibility, experimentation and established use of tobacco products. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Review of Literature on Terminal Box Control, Occupancy Sensing Technology and Multi-zone Demand Control Ventilation (DCV)

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guopeng; Dasu, Aravind R.; Zhang, Jian

    2012-03-01

    This report presents an overall review of the standard requirement, the terminal box control, occupancy sensing technology and DCV. There is system-specific guidance for single-zone systems, but DCV application guidance for multi-zone variable air volume (VAV) systems is not available. No real-world implementation case studies have been found using the CO2-based DCV. The review results also show that the constant minimum air flow set point causes excessive fan power consumption and potential simultaneous heating and cooling. Occupancy-based control (OBC) is needed for the terminal box in order to achieve deep energy savings. Key to OBC is a technology for sensing the actual occupancy of the zone served in real time. Several technologies show promise, but none currently fully meets the need with adequate accuracy and sufficiently low cost.

  20. Ongoing activity in temporally coherent networks predicts intra-subject fluctuation of response time to sporadic executive control demands.

    Science.gov (United States)

    Nozawa, Takayuki; Sugiura, Motoaki; Yokoyama, Ryoichi; Ihara, Mizuki; Kotozaki, Yuka; Miyauchi, Carlos Makoto; Kanno, Akitake; Kawashima, Ryuta

    2014-01-01

    Can ongoing fMRI BOLD signals predict fluctuations in swiftness of a person's response to sporadic cognitive demands? This is an important issue because it clarifies whether intrinsic brain dynamics, for which spatio-temporal patterns are expressed as temporally coherent networks (TCNs), have effects not only on sensory or motor processes, but also on cognitive processes. Predictivity has been affirmed, although to a limited extent. Expecting a predictive effect on executive performance for a wider range of TCNs constituting the cingulo-opercular, fronto-parietal, and default mode networks, we conducted an fMRI study using a version of the color-word Stroop task that was specifically designed to put a higher load on executive control, with the aim of making its fluctuations more detectable. We explored the relationships between the fluctuations in ongoing pre-trial activity in TCNs and the task response time (RT). The results revealed the existence of TCNs in which fluctuations in activity several seconds before the onset of the trial predicted RT fluctuations for the subsequent trial. These TCNs were distributed in the cingulo-opercular and fronto-parietal networks, as well as in perceptual and motor networks. Our results suggest that intrinsic brain dynamics in these networks constitute "cognitive readiness," which plays an active role especially in situations where information for anticipatory attention control is unavailable. Fluctuations in these networks lead to fluctuations in executive control performance.

  1. Smart microgrid hierarchical frequency control ancillary service provision based on virtual inertia concept: An integrated demand response and droop controlled distributed generation framework

    International Nuclear Information System (INIS)

    Rezaei, Navid; Kalantar, Mohsen

    2015-01-01

    Highlights: • Detailed formulation of the microgrid static and dynamic securities based on droop control and virtual inertia concepts. • Constructing a novel objective function using frequency excursion and rate of change of frequency profiles. • Ensuring the microgrid security subject to the microgrid economic and environmental policies. • Coordinated management of demand response and droop controlled distributed generation resources. • Precise scheduling of day-ahead hierarchical frequency control ancillary services using a scenario based stochastic programming. - Abstract: Low inertia stack, high penetration levels of renewable energy source and great ratio of power deviations in a small power delivery system put microgrid frequency at risk of instability. On the basis of the close coupling between the microgrid frequency and system security requirements, procurement of adequate ancillary services from cost-effective and environmental friendly resources is a great challenge requests an efficient energy management system. Motivated by this need, this paper presents a novel energy management system that is aimed to coordinately manage the demand response and distributed generation resources. The proposed approach is carried out by constructing a hierarchical frequency control structure in which the frequency dependent control functions of the microgrid components are modeled comprehensively. On the basis of the derived modeling, both the static and dynamic frequency securities of an islanded microgrid are provided in primary and secondary control levels. Besides, to cope with the low inertia stack of islanded microgrids, novel virtual inertia concept is devised based on the precise modeling of droop controlled distributed generation resources. The proposed approach is applied to typical test microgrid. Energy and hierarchical reserve resource are scheduled precisely using a scenario-based stochastic programming methodology. Moreover, analyzing the

  2. EPICS device support module as ATCA system manager for the ITER fast plant system controller

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Paulo F., E-mail: pricardofc@ipfn.ist.utl.pt [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico – Universidade Técnica de Lisboa, Lisboa (Portugal); Santos, Bruno; Gonçalves, Bruno; Carvalho, Bernardo B.; Sousa, Jorge; Rodrigues, A.P.; Batista, António J.N.; Correia, Miguel; Combo, Álvaro [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico – Universidade Técnica de Lisboa, Lisboa (Portugal); Correia, Carlos M.B.A. [Centro de Instrumentação, Departamento de Física, Universidade de Coimbra, Coimbra (Portugal); Varandas, Carlos A.F. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico – Universidade Técnica de Lisboa, Lisboa (Portugal)

    2013-10-15

    Highlights: ► In Nuclear Fusion, demanding security and high-availability requirements call for redundancy to be available. ► ATCA based Nuclear Fusion Systems are composed by several electronic and mechanical component. ► Control and monitoring of ATCA electronic systems are recommended. ► ITER Fast Plant System Controller Project CODAC system prototype. ► EPICS device support module as External ATCA system manager solution. -- Abstract: This paper presents an Enhanced Physics and Industrial Control System (EPICS) device support module for the International Thermonuclear Experimental Reactor (ITER) Fast Plant System Controller (FPSC) project based in Advanced Telecommunications Computing Architecture (ATCA) specification. The developed EPICS device support module provides an External System Manager (ESM) solution for monitoring and control the ITER FPSC ATCA shelf system and data acquisition boards in order to take proper action and report problems to a control room operator or high level management unit in case of any system failure occurrence. EPICS device support module acts as a Channel Access (CA) server to report problems and publish ATCA system data information to the control room operator, high level management unit or other CA network clients such as Control System Studio Operator Interfaces (CSS OPIs), Best Ever Alarm System Toolkit (BEAST), Best Ever Archive Utility (BEAUTY) or other CA client applications. EPICS device support module communicates with the ATCA Shelf manager (ShM) using HTTP protocol to send and receive commands through POST method in order to get and set system and shelf components properties such as fan speeds measurements, temperatures readings, module status and ATCA boards acquisition and configuration parameters. All system properties, states, commands and parameters are available through the EPICS device support module CA server in EPICS Process Variables (PV) and signals format. ATCA ShM receives the HTTP protocol

  3. Abbreviated Resonant Frequency Training to Augment Heart Rate Variability and Enhance On-Demand Emotional Regulation in Elite Sport Support Staff.

    Science.gov (United States)

    Gross, Mike J; Shearer, David A; Bringer, Joy D; Hall, Ross; Cook, Christian J; Kilduff, Liam P

    2016-09-01

    Support and management staff in elite sport experience work-related stress and emotional disturbance to a similar extent as athletes (Fletcher and Wagstaff 2009). The resonant frequency breathing technique (Lehrer et al. 2000) can inhibit autonomic changes associated with stressful situations or events and as such provides a potential emotional regulation tool. The present study utilised five practitioner-led heart rate variability (HRV) biofeedback sessions and home practice via mobile applications to train support and management staff (n = 9) in resonant frequency breathing techniques. Although baseline HRV did not change from pre to post training, participants increased total HRV (i.e., SDNN; p = .006), parasympathetic HRV (i.e., RMSSD; p = .028) and HRV reflective of baroreflex function (i.e., low frequency power; p = .018) while accurately performing resonant frequency breathing without a breath pacer. Post-intervention questionnaire data revealed an increase (p = .032) in habitual use of somatic strategies for emotional regulation, and social validation data suggested that the technique enhanced emotional regulation at home, work and during international competition. HRV biofeedback and the resonant frequency technique provided an on-demand emotional regulation technique for elite sport support and management staff.

  4. Electrical network capacity support from demand side response: Techno-economic assessment of potential business cases for small commercial and residential end-users

    International Nuclear Information System (INIS)

    Martínez Ceseña, Eduardo A.; Good, Nicholas; Mancarella, Pierluigi

    2015-01-01

    Demand Side Response (DSR) is recognised for its potential to bring economic benefits to various electricity sector actors, such as energy retailers, Transmission System Operators (TSOs) and Distribution Network Operators (DNOs). However, most DSR is provided by large industrial and commercial consumers, and little research has been directed to the quantification of the value that small (below 100 kW) commercial and residential end-users could accrue by providing DSR services. In particular, suitable models and studies are needed to quantify potential business cases for DSR from small commercial and residential end-users. Such models and studies should consider the technical and physical characteristics of the power system and demand resources, together with the economic conditions of the power market. In addition, the majority of research focuses on provision of energy arbitrage or ancillary services, with very little attention to DSR services for network capacity support. Accordingly, this paper presents comprehensive techno-economic methodologies for the quantification of three capacity-based business cases for DSR from small commercial and residential end-users. Case study results applied to a UK context indicate that, if the appropriate regulatory framework is put in place, services for capacity support to both DNOs and TSOs can result into potentially attractive business cases for DSR from small end-users with minimum impact on their comfort level. -- Highlights: •We present three business cases for DSR from domestic and commercial end-users. •A comprehensive techno-economic methodology is proposed for the quantification of each DSR business cases. •The regulatory implications associated with each business case are discussed

  5. Spaceport Command and Control System - Support Software Development

    Science.gov (United States)

    Tremblay, Shayne

    2016-01-01

    The Information Architecture Support (IAS) Team, the component of the Spaceport Command and Control System (SCCS) that is in charge of all the pre-runtime data, was in need of some report features to be added to their internal web application, Information Architecture (IA). Development of these reports is crucial for the speed and productivity of the development team, as they are needed to quickly and efficiently make specific and complicated data requests against the massive IA database. These reports were being put on the back burner, as other development of IA was prioritized over them, but the need for them resulted in internships being created to fill this need. The creation of these reports required learning Ruby on Rails development, along with related web technologies, and they will continue to serve IAS and other support software teams and their IA data needs.

  6. Hardware support for software controlled fast reconfiguration of performance counters

    Science.gov (United States)

    Salapura, Valentina; Wisniewski, Robert W.

    2013-06-18

    Hardware support for software controlled reconfiguration of performance counters may include a plurality of performance counters collecting one or more counts of one or more selected activities. A storage element stores data value representing a time interval, and a timer element reads the data value and detects expiration of the time interval based on the data value and generates a signal. A plurality of configuration registers stores a set of performance counter configurations. A state machine receives the signal and selects a configuration register from the plurality of configuration registers for reconfiguring the one or more performance counters.

  7. Space Station Environmental Control/Life Support System engineering

    Science.gov (United States)

    Miller, C. W.; Heppner, D. B.

    1985-01-01

    The present paper is concerned with a systems engineering study which has provided an understanding of the overall Space Station ECLSS (Environmental Control and Life Support System). ECLSS/functional partitioning is considered along with function criticality, technology alternatives, a technology description, single thread systems, Space Station architectures, ECLSS distribution, mechanical schematics per space station, and Space Station ECLSS characteristics. Attention is given to trade studies and system synergism. The Space Station functional description had been defined by NASA. The ECLSS will utilize technologies which embody regenerative concepts to minimize the use of expendables.

  8. The Atomic Energy Control Board's regulatory research and support program

    International Nuclear Information System (INIS)

    1988-04-01

    The purpose of the Regulatory Research and Support Program is to augment and extend the capability of the Atomic Energy Control Board's (AECB) regulatory program beyond the capability of in-house resources. The overall objective of the program is to produce pertinent and independent scientific and other knowledge and expertise that will assist the AECB in making correct, timely and credible decisions on regulating the development, application and use of atomic energy. The objectives are achieved through contracted research, development, studies, consultant and other kinds of projects administered by the Research and Radiation Protection Branch (RRB) of the AECB

  9. 0-6759 : developing a business process and logical model to support a tour-based travel demand model design for TxDOT.

    Science.gov (United States)

    2013-08-01

    The Texas Department of Transportation : (TxDOT) created a standardized trip-based : modeling approach for travel demand modeling : called the Texas Package Suite of Travel Demand : Models (referred to as the Texas Package) to : oversee the travel de...

  10. Pointing control using a moving base of support.

    Science.gov (United States)

    Hondzinski, Jan M; Kwon, Taegyong

    2009-07-01

    The purposes of this study were to determine whether gaze direction provides a control signal for movement direction for a pointing task requiring a step and to gain insight into why discrepancies previously identified in the literature for endpoint accuracy with gaze directed eccentrically exist. Straight arm pointing movements were performed to real and remembered target locations, either toward or 30 degrees eccentric to gaze direction. Pointing occurred in normal room lighting or darkness while subjects sat, stood still or side-stepped left or right. Trunk rotation contributed 22-65% to gaze orientations when it was not constrained. Error differences for different target locations explained discrepancies among previous experiments. Variable pointing errors were influenced by gaze direction, while mean systematic pointing errors and trunk orientations were influenced by step direction. These data support the use of a control strategy that relies on gaze direction and equilibrium inputs for whole-body goal-directed movements.

  11. Supported Discharge Teams for older people in hospital acute care: a randomised controlled trial.

    Science.gov (United States)

    Parsons, Matthew; Parsons, John; Rouse, Paul; Pillai, Avinesh; Mathieson, Sean; Parsons, Rochelle; Smith, Christine; Kenealy, Tim

    2018-03-01

    Supported Discharge Teams aim to help with the transition from hospital to home, whilst reducing hospital length-of-stay. Despite their obvious attraction, the evidence remains mixed, ranging from strong support for disease-specific interventions to less favourable results for generic services. To determine whether older people referred to a Supported Discharge Team have: (i) reduced length-of-stay in hospital; (ii) reduced risk of hospital readmission; and (iii) reduced healthcare costs. Randomised controlled trial with follow-up to 6 months; 103 older women and 80 men (n = 183) (mean age 79), in hospital, were randomised to receive either Supported Discharge Team or usual care. Home-based rehabilitation was delivered by trained Health Care Assistants up to four times a day, 7 days a week, under the guidance of registered nurses, allied health and geriatricians for up to 6 weeks. Participants randomised to the Supported Discharge Team spent less time in hospital during the index admission (mean 15.7 days) in comparison to usual care (mean 21.6 days) (mean difference 5.9: 95% CI 0.6, 11.3 days: P = 0.03) and spent less time in hospital in the 6 months following discharge home. Supported discharge group costs were calculated at mean NZ$10,836 (SD NZ$12,087) compared to NZ$16,943 (SD NZ$22,303) in usual care. A Supported Discharge Team can provide an effective means of discharging older people home early from hospital and can make a cost-effective contribution to managing increasing demand for hospital beds. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com

  12. IT Security Support for the Spaceport Command Control System Development

    Science.gov (United States)

    Varise, Brian

    2014-01-01

    My job title is IT Security support for the Spaceport Command & Control System Development. As a cyber-security analyst it is my job to ensure NASA's information stays safe from cyber threats, such as, viruses, malware and denial-of-service attacks by establishing and enforcing system access controls. Security is very important in the world of technology and it is used everywhere from personal computers to giant networks ran by Government agencies worldwide. Without constant monitoring analysis, businesses, public organizations and government agencies are vulnerable to potential harmful infiltration of their computer information system. It is my responsibility to ensure authorized access by examining improper access, reporting violations, revoke access, monitor information request by new programming and recommend improvements. My department oversees the Launch Control System and networks. An audit will be conducted for the LCS based on compliance with the Federal Information Security Management Act (FISMA) and The National Institute of Standards and Technology (NIST). I recently finished analyzing the SANS top 20 critical controls to give cost effective recommendations on various software and hardware products for compliance. Upon my completion of this internship, I will have successfully completed my duties as well as gain knowledge that will be helpful to my career in the future as a Cyber Security Analyst.

  13. Demand for male contraception.

    Science.gov (United States)

    Dorman, Emily; Bishai, David

    2012-10-01

    The biological basis for male contraception was established decades ago, but despite promising breakthroughs and the financial burden men increasingly bear due to better enforcement of child support policies, no viable alternative to the condom has been brought to market. Men who wish to control their fertility must rely on female compliance with contraceptives, barrier methods, vasectomy or abstinence. Over the last 10 years, the pharmaceutical industry has abandoned most of its investment in the field, leaving only nonprofit organisations and public entities pursuing male contraception. Leading explanations are uncertain forecasts of market demand pitted against the need for critical investments to demonstrate the safety of existing candidate products. This paper explores the developments and challenges in male contraception research. We produce preliminary estimates of potential market size for a safe and effective male contraceptive based on available data to estimate the potential market for a novel male method.

  14. Speed and path control for conflict-free flight in high air traffic demand in terminal airspace

    Science.gov (United States)

    Rezaei, Ali

    To accommodate the growing air traffic demand, flights will need to be planned and navigated with a much higher level of precision than today's aircraft flight path. The Next Generation Air Transportation System (NextGen) stands to benefit significantly in safety and efficiency from such movement of aircraft along precisely defined paths. Air Traffic Operations (ATO) relying on such precision--the Precision Air Traffic Operations or PATO--are the foundation of high throughput capacity envisioned for the future airports. In PATO, the preferred method is to manage the air traffic by assigning a speed profile to each aircraft in a given fleet in a given airspace (in practice known as (speed control). In this research, an algorithm has been developed, set in the context of a Hybrid Control System (HCS) model, that determines whether a speed control solution exists for a given fleet of aircraft in a given airspace and if so, computes this solution as a collective speed profile that assures separation if executed without deviation. Uncertainties such as weather are not considered but the algorithm can be modified to include uncertainties. The algorithm first computes all feasible sequences (i.e., all sequences that allow the given fleet of aircraft to reach destinations without violating the FAA's separation requirement) by looking at all pairs of aircraft. Then, the most likely sequence is determined and the speed control solution is constructed by a backward trajectory generation, starting with the aircraft last out and proceeds to the first out. This computation can be done for different sequences in parallel which helps to reduce the computation time. If such a solution does not exist, then the algorithm calculates a minimal path modification (known as path control) that will allow separation-compliance speed control. We will also prove that the algorithm will modify the path without creating a new separation violation. The new path will be generated by adding new

  15. User-Preference-Driven Model Predictive Control of Residential Building Loads and Battery Storage for Demand Response: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Baker, Kyri A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Christensen, Dane T. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Isley, Steven C. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-08-21

    This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility and reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.

  16. IT Security Support for Spaceport Command and Control System

    Science.gov (United States)

    McLain, Jeffrey

    2013-01-01

    During the fall 2013 semester, I worked at the Kennedy Space Center as an IT Security Intern in support of the Spaceport Command and Control System under the guidance of the IT Security Lead Engineer. Some of my responsibilities included assisting with security plan documentation collection, system hardware and software inventory, and malicious code and malware scanning. Throughout the semester, I had the opportunity to work on a wide range of security related projects. However, there are three projects in particular that stand out. The first project I completed was updating a large interactive spreadsheet that details the SANS Institutes Top 20 Critical Security Controls. My task was to add in all of the new commercial of the shelf (COTS) software listed on the SANS website that can be used to meet their Top 20 controls. In total, there are 153 unique security tools listed by SANS that meet one or more of their 20 controls. My second project was the creation of a database that will allow my mentor to keep track of the work done by the contractors that report to him in a more efficient manner by recording events as they occur throughout the quarter. Lastly, I expanded upon a security assessment of the Linux machines being used on center that I began last semester. To do this, I used a vulnerability and configuration tool that scans hosts remotely through the network and presents the user with an abundance of information detailing each machines configuration. The experience I gained from working on each of these projects has been invaluable, and I look forward to returning in the spring semester to continue working with the IT Security team.

  17. Optimization and Control for Sharing of the ITER Vacuum Vessel Support Force

    International Nuclear Information System (INIS)

    Rozov, V.

    2006-01-01

    The ITER Vacuum Vessel (VV) is a complex body supported in 9 points below lower ports by restraints in the radial, toroidal and vertical directions. The applied load produces a combination of reaction forces, which must be consistent with the design of the supported object. A reasonable sharing of the load among the supports is important for overall performance of the structure and helps to avoid excessive stress at the joints between the VV and lower ports. Optimization has been performed of the sharing of the total horizontal load applied to the ITER VV between radial and toroidal restraints. An effective method of finding simple parametric relationships between the design parameters of supports and the balance of the reaction forces has been developed. This allows purely analytical prediction of the sharing of the reaction forces for any desired stiffness of the applied restraints with no need for finite element structural analysis, and also allows control of the sharing by a proper selection of parameters of the supports. The method is based on the use of elementary mono-directional schemes - equivalent oscillators built for the main global modes, in static problems. The types of schemes and parameters of their members, related to the a-priori unknown stiffness of the VV structure under the supports, are found from consideration of the free vibration problem for the object using a 3D model of the VV with mass simulators - a series of simple eigenvalue analyses with variation of stiffness of the external restraints, that demands quite moderate computational resources. The equivalent schemes for the main modes not only enable simple one-line analytical calculation of the natural frequencies at any desired stiffness of the supports, but also indicate the contributions and balance of stiffness, to be considered in the static problem. The results of assessments of the reaction forces by direct static structural analyses for several cases are in agreement with values

  18. Controlled Ecological Life Support Systems (CELSS) conceptual design option study

    Science.gov (United States)

    Oleson, Melvin; Olson, Richard L.

    1986-01-01

    Results are given of a study to explore options for the development of a Controlled Ecological Life Support System (CELSS) for a future Space Station. In addition, study results will benefit the design of other facilities such as the Life Sciences Research Facility, a ground-based CELSS demonstrator, and will be useful in planning longer range missions such as a lunar base or manned Mars mission. The objectives were to develop weight and cost estimates for one CELSS module selected from a set of preliminary plant growth unit (PGU) design options. Eleven Space Station CELSS module conceptual PGU designs were reviewed, components and subsystems identified and a sensitivity analysis performed. Areas where insufficient data is available were identified and divided into the categories of biological research, engineering research, and technology development. Topics which receive significant attention are lighting systems for the PGU, the use of automation within the CELSS system, and electric power requirements. Other areas examined include plant harvesting and processing, crop mix analysis, air circulation and atmosphere contaminant flow subsystems, thermal control considerations, utility routing including accessibility and maintenance, and nutrient subsystem design.

  19. A comparative study of long-term energy demand and potential greenhouse gas emission control in Bangladesh

    International Nuclear Information System (INIS)

    Khalaquazzaman, Mohammad

    2005-02-01

    This report presents a comparative study of long-term energy demand and potential greenhouse gas emissions projections from energy demand and supply sectors in Bangladesh covering the period 2000 to 2020. The study was conducted employing the IAEA's tool ENPEP- BALANCE model. This study presents a reliable energy system plan with minimal carbon emission for the country. Primary energy demands distributed by energy carriers and electricity demand have been projected based on macro-economic growth scenarios constructed for national energy policy of 1996. The conservation of indigenous energy resources was emphasized to build a long-term secured energy supply system. The potential energy supply options including nuclear energy and prospective greenhouse gas mitigation options were analyzed

  20. The associations of humorous coping styles, affective states, job demands and job control with the frequency of upper respiratory tract infection

    NARCIS (Netherlands)

    Doosje, S.; De Goede, M.P.M.; Van Doornen, L.J.P.; Van de Schoot, R.

    2011-01-01

    Orientation: There is some evidence that job demands and job resources such as job control and humorous coping may contribute to the risk of upper respiratory tract infections (URTI). Research purpose: The purpose of this study was to test a model including these variables as well as job-related

  1. A multilevel analysis of the demands-control model: Is stress at work determined by factors at the group level or the individual level?

    NARCIS (Netherlands)

    Van Yperen, N.W.; Snijders, T.A.B.

    2000-01-01

    This study explored the extent to which negative health-related outcomes are associated with differences between work groups and with differences between individuals within work groups using R. A. Karasek's (1979) demands-control model. The sample consisted of 260 employees in 31 working groups of a

  2. Application of Karasek's demand/control model a Canadian occupational setting including shift workers during a period of reorganization and downsizing.

    Science.gov (United States)

    Schechter, J; Green, L W; Olsen, L; Kruse, K; Cargo, M

    1997-01-01

    To apply Karasek's Job Content Model to an analysis of the relationships between job type and perceived stress and stress behaviors in a large company during a period of reorganization and downsizing. Cross-sectional mail-out, mail-back survey. A large Canadian telephone/telecommunications company. Stratified random sample (stratified by job category) of 2200 out of 13,000 employees with a response rate of 48.8%. Responses to 25 of Karasek's core questions were utilized to define four job types: low-demand and high control = "relaxed"; high demand and high control = "active"; low demand and low control = "passive", and high demand and low control = "high strain." These job types were compared against self-reported stress levels, perceived general level of health, absenteeism, alcohol use, exercise level, and use of medications and drugs. Similar analyses were performed to assess the influence of shift work. Employees with "passive" or "high strain" job types reported higher levels of stress (trend test p Karasek and Theorell was validated in this setting with respect to stress and some stress-associated attitudes and behaviors.

  3. CO2 sensor versus Volatile Organic Compounds (VOC) sensor – analysis of field measurement data and implications for demand controlled ventilation

    DEFF Research Database (Denmark)

    Kolarik, Jakub

    2014-01-01

    The study investigated performance of two commercially available non-selective metal oxide semiconductor VOC sensors and two commercially available non dispersive infrared CO2 sensors installed in one person office. The office was equipped with demand controlled ventilation. The signals from VOC...

  4. Predicting changes in sleep complaints from baseline values and changes in work demands, work control, and work preoccupation - The WOLF-project

    NARCIS (Netherlands)

    Äkerstedt, T.; Nordin, M.; Alfredsson, L.; Westerholm, P.; Kecklund, L.G.

    2012-01-01

    Study objective: Stress as a cause of disturbed sleep is often taken for granted, but the longitudinal evidence is limited. The aim of this study was to evaluate new cases of poor sleep as a function of changes in reported work demands, work control, and work preoccupation. Methods: Longitudinal

  5. Computation of order and volume fill rates for a base stock inventory control system with heterogeneous demand to investigate which customer class gets the best service

    DEFF Research Database (Denmark)

    Larsen, Christian

    We consider a base stock inventory control system serving two customer classes whose demands are generated by two independent compound renewal processes. We show how to derive order and volume fill rates of each class. Based on assumptions about first order stochastic dominance we prove when one...

  6. Bridging the climate-induced water gap in the twenty-first century: adaptation support based on water supply, demand, adaptation and financing.

    Science.gov (United States)

    Straatsma, Menno; Droogers, Peter; Brandsma, Jaïrus; Buytaert, Wouter; Karssenberg, Derek; Van Beek, Rens; Wada, Yoshihide; Sutanudjaja, Edwin; Vitolo, Claudia; Schmitz, Oliver; Meijer, Karen; Van Aalst, Maaike; Bierkens, Marc

    2014-05-01

    Water scarcity affects large parts of the world. Over the course of the twenty-first century, water demand is likely to increase due to population growth and associated food production, and increased economic activity, while water supply is projected to decrease in many regions due to climate change. Despite recent studies that analyze the effect of climate change on water scarcity, e.g. using climate projections under representative concentration pathways (RCP) of the fifth assessment report of the IPCC (AR5), decision support for closing the water gap between now and 2100 does not exist at a meaningful scale and with a global coverage. In this study, we aimed (i) to assess the joint impact of climatic and socio-economic change on water scarcity, (ii) to integrate impact and potential adaptation in one workflow, (iii) to prioritize adaptation options to counteract water scarcity based on their financial, regional socio-economic and environmental implications, and (iv) to deliver all this information in an integrated user-friendly web-based service. To enable the combination of global coverage with local relevance, we aggregated all results for 1604 water provinces (food producing units) delineated in this study, which is five times smaller than previous food producing units. Water supply was computed using the PCR-GLOBWB hydrological and water resources model, parameterized at 5 arcminutes for the whole globe, excluding Antarctica and Greenland. We ran PCR-GLOBWB with a daily forcing derived from five different GCM models from the CMIP5 (GFDL-ESM2M, Hadgem2-ES, IPSL-CMA5-LR, MIROC-ESM-CHEM, NorESM1-M) that were bias corrected using observation-based WATCH data between 1960-1999. For each of the models all four RCPs (RCP 2.6, 4.5, 6.0, and 8.5) were run, producing the ensemble of 20 future projections. The blue water supply was aggregated per month and per water province. Industrial, domestic and irrigation water demands were computed for a limited number of

  7. Dynamic modeling, experimental evaluation, optimal design and control of integrated fuel cell system and hybrid energy systems for building demands

    Science.gov (United States)

    Nguyen, Gia Luong Huu

    obtained experimental data, the research studied the control of airflow to regulate the temperature of reactors within the fuel processor. The dynamic model provided a platform to test the dynamic response for different control gains. With sufficient sensing and appropriate control, a rapid response to maintain the temperature of the reactor despite an increase in power was possible. The third part of the research studied the use of a fuel cell in conjunction with photovoltaic panels, and energy storage to provide electricity for buildings. This research developed an optimization framework to determine the size of each device in the hybrid energy system to satisfy the electrical demands of buildings and yield the lowest cost. The advantage of having the fuel cell with photovoltaic and energy storage was the ability to operate the fuel cell at baseload at night, thus reducing the need for large battery systems to shift the solar power produced in the day to the night. In addition, the dispatchability of the fuel cell provided an extra degree of freedom necessary for unforeseen disturbances. An operation framework based on model predictive control showed that the method is suitable for optimizing the dispatch of the hybrid energy system.

  8. Measurement approaches to support future warhead arms control transparency

    International Nuclear Information System (INIS)

    Olinger, C.T.; Frankle, C.M.; Johnson, M.W.; Poths, J.

    1998-01-01

    Transparency on warhead stockpiles, warhead dismantlement, and fissile material stockpiles in nuclear weapons states will become increasingly important in the move beyond START II toward lower quantities of warheads. Congressional support for further warhead reductions will likely depend on the degree of irreversibility, or in other words, the rapidity with which warhead inventories could be reconstituted. Whether irreversibility considerations can be satisfied will depend on monitoring dismantlement as well as constraining the available stockpile of fissile materials for possible refabrication into warheads. Measurement techniques designed to address the above problems will need to consider NPT Article 1 obligations as well as Russian and US classification regulations, which prohibit or restrict the transfer of nuclear warhead design information to other states. Classification considerations currently limit the potential completeness of future inspections of weapons materials. Many conventional international safeguards approaches are not currently viable for arms control applications because they would reveal weapons design information. The authors discuss a variety of technical measures that may help to improve transparence of warhead and fissile material stockpiles and may enable limited warhead dismantlement transparency

  9. Distributed sensor architecture for intelligent control that supports quality of control and quality of service.

    Science.gov (United States)

    Poza-Lujan, Jose-Luis; Posadas-Yagüe, Juan-Luis; Simó-Ten, José-Enrique; Simarro, Raúl; Benet, Ginés

    2015-02-25

    This paper is part of a study of intelligent architectures for distributed control and communications systems. The study focuses on optimizing control systems by evaluating the performance of middleware through quality of service (QoS) parameters and the optimization of control using Quality of Control (QoC) parameters. The main aim of this work is to study, design, develop, and evaluate a distributed control architecture based on the Data-Distribution Service for Real-Time Systems (DDS) communication standard as proposed by the Object Management Group (OMG). As a result of the study, an architecture called Frame-Sensor-Adapter to Control (FSACtrl) has been developed. FSACtrl provides a model to implement an intelligent distributed Event-Based Control (EBC) system with support to measure QoS and QoC parameters. The novelty consists of using, simultaneously, the measured QoS and QoC parameters to make decisions about the control action with a new method called Event Based Quality Integral Cycle. To validate the architecture, the first five Braitenberg vehicles have been implemented using the FSACtrl architecture. The experimental outcomes, demonstrate the convenience of using jointly QoS and QoC parameters in distributed control systems.

  10. Distributed Sensor Architecture for Intelligent Control that Supports Quality of Control and Quality of Service

    Directory of Open Access Journals (Sweden)

    Jose-Luis Poza-Lujan

    2015-02-01

    Full Text Available This paper is part of a study of intelligent architectures for distributed control and communications systems. The study focuses on optimizing control systems by evaluating the performance of middleware through quality of service (QoS parameters and the optimization of control using Quality of Control (QoC parameters. The main aim of this work is to study, design, develop, and evaluate a distributed control architecture based on the Data-Distribution Service for Real-Time Systems (DDS communication standard as proposed by the Object Management Group (OMG. As a result of the study, an architecture called Frame-Sensor-Adapter to Control (FSACtrl has been developed. FSACtrl provides a model to implement an intelligent distributed Event-Based Control (EBC system with support to measure QoS and QoC parameters. The novelty consists of using, simultaneously, the measured QoS and QoC parameters to make decisions about the control action with a new method called Event Based Quality Integral Cycle. To validate the architecture, the first five Braitenberg vehicles have been implemented using the FSACtrl architecture. The experimental outcomes, demonstrate the convenience of using jointly QoS and QoC parameters in distributed control systems.

  11. Factorial invariance, scale reliability, and construct validity of the job control and job demands scales for immigrant workers: The Multi-Ethnic Study of Atherosclerosis (MESA)

    Science.gov (United States)

    Fujishiro, Kaori; Landsbergis, Paul; Roux, Ana V. Diez; Stukovsky, Karen Hinckley; Shrager, Sandi; Baron, Sherry

    2014-01-01

    Immigrants have a different social context from those who stay in their home country or those who were born to the country that immigrants now live. Cultural theory of risk perception suggests that social context influences one’s interpretation of questionnaire items. We examined psychometric properties of job control and job demand scales with US- and foreign-born workers who preferred English, Spanish, or Chinese (n=3114, mean age=58.1). Across all groups, the job control scale had acceptable Cronbach’s alpha (0.78–0.83) and equivalent factor loadings (ΔCFIjob demands scale regardless of language, education, or age of migration. Two job-demand items had different factor loadings across groups. Among immigrants, both scales had inconsistent associations with perceived job stress and self-rated health. For a better understanding of immigrants’ job stress, the concept of job demands should be expanded and immigrants’ expectations for job control explored. (149/150 limit) PMID:20582720

  12. Performance improvement of a drop-on-demand inkjet printhead using an optimization-based feedforward control method

    NARCIS (Netherlands)

    Khalate, A.; Bombois, X.; Babuska, R.; Wijshoff, H.M.A.; Waarsing, R.

    2011-01-01

    The printing quality delivered by a drop-on-demand (DoD) inkjet printhead is limited due to the residual oscillations in the ink channel. The maximal jetting frequency of a DoD inkjet printhead can be increased by quickly damping the residual oscillations and by bringing in this way the ink channel

  13. Quantifying demand flexibility of power-to-heat and thermal energy storage in the control of building heating systems

    NARCIS (Netherlands)

    Finck, C.J.; Li, R.; Kramer, R.P.; Zeiler, W.

    2018-01-01

    In the future due to continued integration of renewable energy sources, demand-side flexibility would be required for managing power grids. Building energy systems will serve as one possible source of energy flexibility. The degree of flexibility provided by building energy systems is highly

  14. Derivation of confidence intervals of service measures in a base-stock inventory control system with low-frequent demand

    DEFF Research Database (Denmark)

    Larsen, Christian

    We explore a base-stock system with backlogging where the demand process is a compound renewal process and the compound element is a delayed geometric distribution. For this setting it is proven in [4] that the long-run average service measures order fill rate (OFR) and volume fill rate (VFR) are...

  15. Derivation of confidence intervals of service measures in a base-stock inventory control system with low-frequent demand

    DEFF Research Database (Denmark)

    Larsen, Christian

    2011-01-01

    We explore a base-stock system with backlogging where the demand process is a compound renewal process and the compound element is a delayed geometric distribution. For this setting it holds that the long-run average service measures order fill rate (OFR) and volume fill rate (VFR) are equal in v...

  16. Frequency Support of PMSG-WTG Based on Improved Inertial Control: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z.; Wang, X.; Gao, W.; Kang, M.; Hwang, M.; Kang, Y.; Gevorgian, Vahan; Muljadi, Eduard

    2016-03-15

    With increasing integrations of large-scale systems based on permanent magnet synchronous generator wind turbine generators (PMSG-WTGs), the overall inertial response of a power system will tend to deteriorate as a result of the decoupling of rotor speed and grid frequency through the power converter as well as the scheduled retirement of conventional synchronous generators. Thus, PMSG-WTGs can provide value to an electric grid by contributing to the system's inertial response by utilizing the inherent kinetic energy stored in their rotating masses and fast power control. In this work, an improved inertial control method based on the maximum power point tracking operation curve is introduced to enhance the overall frequency support capability of PMSG-WTGs in the case of large supply-demand imbalances. Moreover, this method is implemented in the CART2-PMSG integrated model in MATLAB/Simulink to investigate its impact on the wind turbine's structural loads during the inertial response process. Simulation results indicate that the proposed method can effectively reduce the frequency nadir, arrest the rate of change of frequency, and mitigate the secondary frequency drop while imposing no negative impact on the major mechanical components of the wind turbine.

  17. Robotics in a controlled, ecological life support system

    Science.gov (United States)

    Miles, Gaines E.; Krom, Kimberly J.

    1993-01-01

    Controlled, Ecological Life Support Systems (CELSS) that utilize plants to provide food, water and oxygen could consume considerable amounts of labor unless crop production, recovery and processing are automated. Robotic manipulators equipped with special end-effectors and programmed to perform the sensing and materials handling tasks would minimize the amount of astronaut labor required. The Human Rated Test Facility (HRTF) planned for Johnson Space Center could discover and demonstrate techniques of crop production which can be reliably integrated with machinery to minimize labor requirements. Before the physical components (shelves, lighting fixtures, etc.) can be selected, a systems analysis must be performed to determine which alternative processes should be followed and how the materials handling tasks should be automated. Given that the current procedures used to grow crops in a CELSS may not be the best methods to automate, then what are the alternatives? How may plants be grown, harvested, processed for food, and the inedible components recycled? What commercial technologies current exist? What research efforts are underway to develop new technologies which might satisfy the need for automation in a CELSS? The answers to these questions should prove enlightening and provide some of the information necessary to perform the systems analysis. The planting, culturing, gathering, threshing and separation, food processing, and recovery of inedible portions of wheat were studied. The basic biological and materials handling processes of each task are defined and discussed. Current practices at Johnson Space Center and other NASA centers are described and compared to common production practices in the plant production industry. Technologies currently being researched which might be applicable are identified and illustrated. Finally, based on this knowledge, several scenarios are proposed for automating the tasks for wheat.

  18. In demand

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, B. [Bridgestone Ltd. (United Kingdom)

    2005-11-01

    The paper explains how good relationships can help alleviate potential tyre shortages. Demand for large dump truck tyres (largely for China) has increased by 50% within 12 months. Bridgestone's manufacturing plants are operating at maximum capacity. The company supplies tyres to all vehicles at Scottish Coal's opencast coal mines. Its Tyre Management System (TMS) supplied free of charge to customers helps maximise tyre life and minimise downtime from data on pressure, tread and general conditions fed into the hand-held TMS computer. 3 photos.

  19. Work Stress and Depression among Direct Support Professionals: The Role of Work Support and Locus of Control

    Science.gov (United States)

    Gray-Stanley, J. A.; Muramatsu, N.; Heller, T.; Hughes, S.; Johnson, T. P.; Ramirez-Valles, J.

    2010-01-01

    Background: Although work stress can impede the capacity of direct support professionals and contribute to mental health challenges, external (i.e. work social support) and internal resources (i.e. an internal locus of control) have been shown to help DSPs cope more actively. We examined how work stress was associated with depression, with a…

  20. Mission Control Operations: Employing a New High Performance Design for Communications Links Supporting Exploration Programs

    Science.gov (United States)

    Jackson, Dan E., Jr.

    2015-01-01

    The planetary exploration programs demand a totally new examination of data multiplexing, digital communications protocols and data transmission principles for both ground and spacecraft operations. Highly adaptive communications devices on-board and on the ground must provide the greatest possible transmitted data density between deployed crew personnel, spacecraft and ground control teams. Regarding these requirements, this proposal borrows from research into quantum mechanical computing by applying the concept of a qubit, a single bit that represents 16 states, to radio frequency (RF) communications link design for exploration programs. This concept of placing multiple character values into a single data bit can easily make the evolutionary steps needed to meet exploration mission demands. To move the qubit from the quantum mechanical research laboratory into long distance RF data transmission, this proposal utilizes polarization modulation of the RF carrier signal to represent numbers from zero to fifteen. It introduces the concept of a binary-to-hexadecimal converter that quickly chops any data stream into 16-bit words and connects variously polarized feedhorns to a single-frequency radio transmitter. Further, the concept relies on development of a receiver that uses low-noise amplifiers and an antenna array to quickly assess carrier polarity and perform hexadecimal to binary conversion. Early testbed experiments using the International Space Station (ISS) as an operations laboratory can be implemented to provide the most cost-effective return for research investment. The improvement in signal-to-noise ratio while supporting greater baseband data rates that could be achieved through this concept justifies its consideration for long-distance exploration programs.

  1. Optimal Control Method for Wind Farm to Support Temporary Primary Frequency Control with Minimized Wind Energy Cost

    DEFF Research Database (Denmark)

    Wang, Haijiao; Chen, Zhe; Jiang, Quanyuan

    2015-01-01

    This study proposes an optimal control method for variable speed wind turbines (VSWTs) based wind farm (WF) to support temporary primary frequency control. This control method consists of two layers: temporary frequency support control (TFSC) of the VSWT, and temporary support power optimal...... dispatch (TSPOD) of the WF. With TFSC, the VSWT could temporarily provide extra power to support system frequency under varying and wide-range wind speed. In the WF control centre, TSPOD optimally dispatches the frequency support power orders to the VSWTs that operate under different wind speeds, minimises...... the wind energy cost of frequency support, and satisfies the support capabilities of the VSWTs. The effectiveness of the whole control method is verified in the IEEE-RTS built in MATLABSimulink, and compared with a published de-loading method....

  2. Analytical tools and functions of GIS in the process control and decision support of mining company

    Directory of Open Access Journals (Sweden)

    Semrád Peter

    2001-12-01

    Full Text Available The development of computer techniques, the increase in demands for the professional and possible fastest data processing, as well as for the fluency and efficiency of information gaining, exchanging and providing has a strong influence on forming the new generation of information technologies - Geografic Information Systems (GIS that rose in the second half of the twentieth century.Advancement in this area is still progressing and GIS gradually find the enforcement in individual fields where they play a great role in the process control and decision support. Nowadays, there are applications in mining and geology, where are used especially at processing and evaluating of mining - geological documentation, optimalization of mining and technical processes, planning, distributing and managing of mining as well as economic analysis that are important in terms of investment decisions to mining business.GIS are the systems for the effective keeping, updating, processing, analysing, modelling, simulating and presenting geographically oriented information. We can identify them as computer systems helping to solve real problems that should be normally required to solve by human expert.Well equipped GIS have graphic ability and accordingly manage descriptive (attribute data. They are able to secure mutual connection between graphical and descriptive data and in addition to command countless number of functions that enable the execution of spatial analysis. This fact is very important in mining and geological application.There are exploited mostly geostatistical analysis (e. g. modelling of distribution valuable and harmful components of mineral resouce in a mineral deposit, surface modelling and surface model analysis (e. g. at modelling the subsidence of mining territory, different methods of creating spatial and attribute queries about database for seeking necessary data (e. g. to find all mining blocks of deposit that meet required conditions and to

  3. Applications and Energy Consumption of Demand Controlled Ventilation Systems. Modelling, Simulation and Implementation of Modular Built Dynamical VAV Systems and Control Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Bjoern R.

    2002-07-01

    This thesis discusses many topics of heating and ventilation. This is because the ventilation system is an integrated part of its host building. The functionality and effectiveness of the ventilation system are very much dependent on the building's architectural design, its internal materials, its occupants, its air tightness characteristics and its placement in the terrain. Although this thesis emphasizes strongly on VAV (Variable Air Volume) systems and, in particular, modelling and simulation of such systems, it touches a range of important HVAC related issues. The scope is however, limited to the field of comfort ventilation. That is because ventilation in industrial environments often is subject to separate regulations, and requires other and specialized methods of design and evaluation of ventilation performance. The main objectives have been to: (1) Develop mathematical models for VAV components and systems. (2) Evaluate existing and develop new strategies for VAV demand controlled ventilation by system simulation. (3) Investigate the potential for saving energy and the impact on indoor climate. The development of mathematical models and simulation of VAV systems are given quite much attention compared to the other topics discussed.

  4. From rationing to energy saving certificates. Four decades of power demand control in France and United Kingdom

    International Nuclear Information System (INIS)

    Pautard, Eric

    2012-01-01

    From 'saving energy' awareness campaign to financial incentives for efficient technologies, from rationing to energy efficiency commitment, from monopolistic public management to compelling involvement of the electricity-supply market, from economic stakes to ecological issues, Demand-Side Management policies have changed over time. This paper analyzes this historical background in order to examine the effects of the electricity market deregulation in France and United Kingdom

  5. Supporting Control Room Operators in Highly Automated Future Power Networks

    DEFF Research Database (Denmark)

    Chen, Minjiang; Catterson, Victoria; Syed, Mazheruddin

    2017-01-01

    Operating power systems is an extremely challenging task, not least because power systems have become highly interconnected, as well as the range of network issues that can occur. It is therefore a necessity to develop decision support systems and visualisation that can effectively support the hu...... the human operators for decisionmaking in the complex and dynamic environment of future highly automated power system. This paper aims to investigate the decision support functions associated with frequency deviation events for the proposed Web of Cells concept....

  6. Demand response in a market environment

    DEFF Research Database (Denmark)

    Larsen, Emil Mahler

    This thesis addresses the design, deployment and benefits of demand response in a market environment. Demand response is consumption that can be controlled by an external stimulus in the power system. Flexible consumption is a useful tool for absorbing volatile power from renewable sources like...... this simulation, real power system data from the Danish island of Bornholm is introduced and methods to quantify an aggregated load is developed. These methods can be used for real-time operation and to support investment decisions. More specifically, they can be used to forecast the response to electricity...... pricing and to classify different types of customers. The proposed models are then embedded into new fiveminute electricity markets for system balancing and local congestion management. New market tools for exploiting and maintaining a degree of control over demand are developed, and the value of DR using...

  7. Instrumentation and Controls Division, Technical Support Department Management Plan, FY 1993--FY 1996

    Energy Technology Data Exchange (ETDEWEB)

    Adkisson, B.P.; Kunselman, C.W.; Effler, R.P.; Miller, D.R.; Millet, A.J.; Stansberry, C.T.

    1993-08-01

    This report describes the organization, key functions, and major activities of the Technical Support Department The Department is the programmatic support element of the Instrumentation and Controls Division. The Department`s primary focus is the support of existing equipment and systems at Oak Ridge National Laboratory that are generally characterized as instrumentation and controls. The support takes the form of repair, calibration, fabrication, field engineering, preventive maintenance, software support, and record keeping.

  8. Exploring the Impact of Network Structure and Demand Collaboration on the Dynamics of a Supply Chain Network Using a Robust Control Approach

    Directory of Open Access Journals (Sweden)

    Yongchang Wei

    2015-01-01

    uncertain environment. The impact of network structure and collaboration on the dynamics and robustness of supply chain network, however, remains to be explored. In this paper, a unified state space model for a two-layer supply chain network composed of multiple distributors and multiple retailers is developed. A robust control algorithm is advocated to reduce both order and demand fluctuations for unknown demand. Numerical simulations demonstrate that the robust control approach has the advantage to reduce both inventory and order fluctuations. In the simulation experiment, it is interesting to notice that complex network structure and collaborations might contribute to the reduction of inventory and order oscillations. This paper yields new insights into the overestimated bullwhip effect problem and helps us understand the complexities of supply chain networks.

  9. Supporting Air and Space Expeditionary Forces: Expanded Operational Architecture for Combat Support Execution Planning and Control

    National Research Council Canada - National Science Library

    Mills, Patrick; Evers, Ken; Kinlin, Donna; Tripp, Robert S

    2006-01-01

    During the past decade, the U.S. military has supported continuous deployments of forces around the world, often on very short notice and for prolonged duration, to meet the needs of a wide range of peacekeeping and humanitarian...

  10. A Distributed Control System Prototyping Environment to Support Control Room Modernization

    Energy Technology Data Exchange (ETDEWEB)

    Lew, Roger Thomas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Boring, Ronald Laurids [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ulrich, Thomas Anthony [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-12-01

    Operators of critical processes, such as nuclear power production, must contend with highly complex systems, procedures, and regulations. Developing human-machine interfaces (HMIs) that better support operators is a high priority for ensuring the safe and reliable operation of critical processes. Human factors engineering (HFE) provides a rich and mature set of tools for evaluating the performance of HMIs, however the set of tools for developing and designing HMIs is still in its infancy. Here we propose a rapid prototyping approach for integrating proposed HMIs into their native environments before a design is finalized. This approach allows researchers and developers to test design ideas and eliminate design flaws prior to fully developing the new system. We illustrate this approach with four prototype designs developed using Microsoft’s Windows Presentation Foundation (WPF). One example is integrated into a microworld environment to test the functionality of the design and identify the optimal level of automation for a new system in a nuclear power plant. The other three examples are integrated into a full-scale, glasstop digital simulator of a nuclear power plant. One example demonstrates the capabilities of next generation control concepts; another aims to expand the current state of the art; lastly, an HMI prototype was developed as a test platform for a new control system currently in development at U.S. nuclear power plants. WPF possesses several characteristics that make it well suited to HMI design. It provides a tremendous amount of flexibility, agility, robustness, and extensibility. Distributed control system (DCS) specific environments tend to focus on the safety and reliability requirements for real-world interfaces and consequently have less emphasis on providing functionality to support novel interaction paradigms. Because of WPF’s large user-base, Microsoft can provide an extremely mature tool. Within process control applications,WPF is

  11. The associations of humorous coping styles, affective states, job demands and job control with the frequency of upper respiratory tract infection

    Directory of Open Access Journals (Sweden)

    Sibe Doosje

    2011-05-01

    Research purpose: The purpose of this study was to test a model including these variables as well as job-related affect, in order to explore their role in the explanation of the frequency of upper respiratory tract infection. Motivation of the study: This study has been conducted in order to extend our understanding of the role of traditional variables like job demands and job control with humorous coping styles and affective variables with regard to the explanation of the frequency of URTI. Research design, approach and method: A sample of 2094 employees filled out questionnaires assessing job demands, job control, generic (MSHS-C, antecedent-focused and responsefocused humorous coping (QOHC and job-related affect (JAWS. Main findings: Job demands were indirectly related to the frequency of upper respiratory tract infections, mediated by their relationships with job control and negative job-related affect. Generic and response-focused humorous coping were less relevant for the explanation of the frequency of upper respiratory tract infections than the presumably ‘healthy’ antecedentfocused humorous coping style. The latter showed a negative association with negative jobrelated affect. The frequency of upper respiratory tract infections was better predicted by job control and negative job-related affect than by humorous coping, in the expected directions. Practical/managerial implication: These findings may have practical relevance for the improvement of stress management interventions in organisations. Contribution/value-add: Although it was shown that healthy humorous coping does contribute to decreases in upper respiratory tract infection, job demands, job resources and negative affective state seem the most important predictors.

  12. PERIODIC REVIEW SYSTEM FOR INVENTORY REPLENISHMENT CONTROL FOR A TWO-ECHELON LOGISTICS NETWORK UNDER DEMAND UNCERTAINTY: A TWO-STAGE STOCHASTIC PROGRAMING APPROACH

    OpenAIRE

    Cunha, P.S.A.; Oliveira, F.; Raupp, Fernanda M.P.

    2017-01-01

    ABSTRACT Here, we propose a novel methodology for replenishment and control systems for inventories of two-echelon logistics networks using a two-stage stochastic programming, considering periodic review and uncertain demands. In addition, to achieve better customer services, we introduce a variable rationing rule to address quantities of the item in short. The devised models are reformulated into their deterministic equivalent, resulting in nonlinear mixed-integer programming models, which a...

  13. Computation of order and volume fill rates for a base stock inventory control system with heterogeneous demand to investigate which customer class gets the best service

    OpenAIRE

    Larsen, Christian

    2006-01-01

    We consider a base stock inventory control system serving two customer classes whose demands are generated by two independent compound renewal processes. We show how to derive order and volume fill rates of each class. Based on assumptions about first order stochastic dominance we prove when one customer class will get the best service. That theoretical result is validated through a series of numerical experiments which also reveal that it is quite robust.

  14. A comparison between the order and the volume fill rates for a base-stock inventory control system under a compound renewal demand process

    OpenAIRE

    Larsen, Christian; Thorstenson, Anders

    2006-01-01

    The order fill rate is less commonly used than the volume fill rate (most often just denoted fill rate) as a performance measure for inventory control systems. However, in settings where the focus is on filling customer orders rather than total quantities, the order fill rate should be the preferred measure. In this paper we consider a continuous review, base-stock policy, where all replenishment orders have the same constant lead time and all unfilled demands are backordered. We develop exac...

  15. DemandStat

    International Nuclear Information System (INIS)

    2003-01-01

    DemandStat is an accurate and up-to-date international statistics database dedicated to energy demand, with an unrivaled level of details for powerful market analysis. It provides detailed consumption statistics (30 sectors) on all energies, detailed 2003 data and historical annual data since 1970, frequent data revision and update (2 updates options), 150 data sources gathered and expertized, all data on a single database Consistent and homogeneous statistics, in line with all major data providers (IEA, Eurostat, ADB, OLADE, etc), no ruptures in time-series with easy request building and data analysis and reactive support from data experts. (A.L.B.)

  16. The GMOC Model : Supporting Development of Systems for Human Control

    OpenAIRE

    Tschirner, Simon

    2015-01-01

    Train traffic control is a complex task in a dynamic environment. Different actors have to cooperate to meet strong requirements regarding safety, punctuality, capacity utilization, energy consumption, and more. The GMOC model has been developed and utilized in a number of studies in several different areas. This thesis describes GMOC and uses train traffic control as the application area for evaluating its utility. The GMOC model has its origin in control theory and relates to concepts of dy...

  17. Supporting Development of Satellite's Guidance Navigation and Control Software: A Product Line Approach

    Science.gov (United States)

    McComas, David; Stark, Michael; Leake, Stephen; White, Michael; Morisio, Maurizio; Travassos, Guilherme H.; Powers, Edward I. (Technical Monitor)

    2000-01-01

    The NASA Goddard Space Flight Center Flight Software Branch (FSB) is developing a Guidance, Navigation, and Control (GNC) Flight Software (FSW) product line. The demand for increasingly more complex flight software in less time while maintaining the same level of quality has motivated us to look for better FSW development strategies. The GNC FSW product line has been planned to address the core GNC FSW functionality very similar on many recent low/near Earth missions in the last ten years. Unfortunately these missions have not accomplished significant drops in development cost since a systematic approach towards reuse has not been adopted. In addition, new demands are continually being placed upon the FSW which means the FSB must become more adept at providing GNC FSW functionality's core so it can accommodate additional requirements. These domain features together with engineering concepts are influencing the specification, description and evaluation of FSW product line. Domain engineering is the foundation for emerging product line software development approaches. A product line is 'A family of products designed to take advantage of their common aspects and predicted variabilities'. In our product line approach, domain engineering includes the engineering activities needed to produce reusable artifacts for a domain. Application engineering refers to developing an application in the domain starting from reusable artifacts. The focus of this paper is regarding the software process, lessons learned and on how the GNC FSW product line manages variability. Existing domain engineering approaches do not enforce any specific notation for domain analysis or commonality and variability analysis. Usually, natural language text is the preferred tool. The advantage is the flexibility and adapt ability of natural language. However, one has to be ready to accept also its well-known drawbacks, such as ambiguity, inconsistency, and contradictions. While most domain analysis

  18. Instrumentation and control activities at the electric power research institute to support computerized support systems

    International Nuclear Information System (INIS)

    Naser, J.

    1996-01-01

    Most nuclear power plants in the United States are operating with their original analog I and C equipment. This equipment requires increasing maintenance efforts to sustain systems performance. Decreasing availability of replacement parts and support organization for analog technology accentuate obsolescence problems and resultant O and M cost increases. Modern technology, especially digital systems, offers improved functionality, performance, and reliability; solutions to obsolescence of equipment; reduction in O and M costs; and the potential to enhance safety. Digital systems, including computerized support systems, with their inherent advantages will be implemented only if reliable and cost-effective implementation and licensing acceptance is achieved and if the upgraded systems supports reduced power production costs. EPRI and its member utilities are working together under the Integrated I and C Upgrade Initiative to address I and C issues. (author). 23 refs

  19. The environmental control and life support system advanced automation project

    Science.gov (United States)

    Dewberry, Brandon S.

    1991-01-01

    The objective of the ECLSS Advanced Automation project includes reduction of the risk associated with the integration of new, beneficial software techniques. Demonstrations of this software to baseline engineering and test personnel will show the benefits of these techniques. The advanced software will be integrated into ground testing and ground support facilities, familiarizing its usage by key personnel.

  20. Decision support for dynamic greenhouse climate control strategies

    NARCIS (Netherlands)

    Körner, O.; Straten, van G.

    2008-01-01

    Earlier, different dynamic greenhouse climate regimes were designed with various aims as energy saving, biocide reduction or reduction of chemical growth retardants that are used for quality improvement. The aim of this research was to create a decision support tool in order to decide at which week

  1. A Novel Intelligent Transportation Control Supported by Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Zhe Qian

    2013-05-01

    Full Text Available With the development of wireless sensor unit, and improvement of real-time and quality of wireless communication, the intelligent transportation control system employ these technologies to realize sensing, positioning, computing, and communication for voiding collisions. This paper discusses the framework of transportation control system, and emphases TDOA positioning algorithm and the new weighted least square optimization method. The simulation result shows that, our method achieves high-accuracy of positioning, which can satisfy the need of transportation control. Finally, we outline the urgent work need to address in the future.

  2. EDP supported control room simulation for training of fault cases

    International Nuclear Information System (INIS)

    Weber, P.

    1984-01-01

    The picture used for simulation was the model of a power station control room designed by KWU for the German Museum, the cooling water circuit of which is illustrated, in order to avoid long training times by a manageable problem setting. A process video system equipped with a light pen made by KRUPP ATLAS was available for the VDU representation of simulation, which is used in industry, for the control and supervision of technical system. This process video system was controlled by a Digital PDP 11/40, which has several great advantages over stand-alone operation. (orig./DG) [de

  3. An infrastructure with a unified control plane to integrate IP into optical metro networks to provide flexible and intelligent bandwidth on demand for cloud computing

    Science.gov (United States)

    Yang, Wei; Hall, Trevor

    2012-12-01

    The Internet is entering an era of cloud computing to provide more cost effective, eco-friendly and reliable services to consumer and business users and the nature of the Internet traffic will undertake a fundamental transformation. Consequently, the current Internet will no longer suffice for serving cloud traffic in metro areas. This work proposes an infrastructure with a unified control plane that integrates simple packet aggregation technology with optical express through the interoperation between IP routers and electrical traffic controllers in optical metro networks. The proposed infrastructure provides flexible, intelligent, and eco-friendly bandwidth on demand for cloud computing in metro areas.

  4. Integrated Control Strategies Supporting Autonomous Functionalities in Mobile Robots

    National Research Council Canada - National Science Library

    Sights, B; Everett, H. R; Pacis, E. B; Kogut, G; Thompson, M

    2005-01-01

    High-level intelligence allows a mobile robot to create and interpret complex world models, but without a precise control system, the accuracy of the world model and the robot's ability to interact...

  5. Affordances and Constraints of Intelligent Decision Support for Military Command and Control : Three Case Studies of Support Systems

    OpenAIRE

    Leifler, Ola

    2011-01-01

    Researchers in military command and control (C2) have for several decades sought to help commanders by introducing automated, intelligent decision support systems. These systems are still not widely used, however, and some researchers argue that this may be due to those problems that are inherent in the relationship between the affordances of technology and the requirements by the specific contexts of work in military C2. In this thesis, we study some specific properties of three support tech...

  6. Demandas do trabalho e controle: implicações em unidades de terapia intensiva pediátrica e neonatal Demandas y control del trabajo: implicaciones en las unidades de tratamiento intensivo pediatrico y neonatal Demands and control of work: implications in pediatric and neonatal intensive care units

    Directory of Open Access Journals (Sweden)

    Monalisa de Cássia Fogaça

    2010-08-01

    Full Text Available Comparar a demanda e o controle sobre trabalho de médicos e enfermeiros que trabalham em unidades de tratamento intensivo pediátrica e neonatal. Estudo transversal com 37 médicos e 20 enfermeiros. Utilizou-se o Job Content Questionnarie. Médicos da UTI Neonatal diferem em suporte social recebido do supervisor (p=0,01 em relação aos da UTI Pediátrica. Enfermeiros da UTI Neonatal apresentam insegurança no trabalho (p=0,05. Médicos e enfermeiros da UTI Pediátrica diferem em controle sobre o trabalho; demanda psicológica do trabalho; esforço físico e suporte do supervisor (pComparación de la demanda y control sobre el trabajo de los médicos y enfermeras que trabajan en las unidades de tratamiento intensivo pediátrico y neonatal. Estudio transversal con 37 médicos y 20 enfermeras. Se utilizó el Job Content Questionnarie. Los médicos de la UCI Neonatal difieren en el apoyo social recibido desde el supervisor (p= 0,01 en comparacion com la UCI Pediátrica. Enfermeras de la UCI Neonatal actualmente la inseguridad en el empleo (p = 0,05. Los médicos y enfermeras de la UCI Pediátrica difieren em el control sobre el trabajo, las exigencias psicológicas del trabajo, esfuerzo físico y el apoyo del supervisor (pTo compare the demand and control over work of physicians and nurses working in pediatric and neonatal critical care units. Cross-sectional study with 37 doctors and 20 nurses. We used the Job Content Questionnarie. Physicians from the ICU Neonatal differ in social support received from the supervisor (p= 0.01 compared to the ICU Pediatric. ICU nurses of the Neonatal present job insecurity (p= 0.05. Physicians and nurses from the ICU Pediatric differ in control over the work, psychological demands of work, physical effort and support of the supervisor (p <0.05. Physicians and nurses from the ICU Neonatal show statistical differences in control over the work, physical effort and support of the supervisor (p<0.05. The work

  7. A smartphone-supported weight loss program: design of the ENGAGED randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Pellegrini Christine A

    2012-11-01

    Full Text Available Abstract Background Obesity remains a major public health challenge, demanding cost-effective and scalable weight management programs. Delivering key treatment components via mobile technology offers a potential way to reduce expensive in-person contact, thereby lowering the cost and burden of intensive weight loss programs. The ENGAGED study is a theory-guided, randomized controlled trial designed to examine the feasibility and efficacy of an abbreviated smartphone-supported weight loss program. Methods/design Ninety-six obese adults (BMI 30–39.9 kg/m2 will be randomized to one of three treatment conditions: (1 standard behavioral weight loss (STND, (2 technology-supported behavioral weight loss (TECH; or (3 self-guided behavioral weight loss (SELF. All groups will aim to achieve a 7% weight loss goal by reducing calorie and fat intake and progressively increasing moderate intensity physical activity to 175 minutes/week. STND and TECH will attend 8 group sessions and receive regular coaching calls during the first 6 months of the intervention; SELF will receive the Group Lifestyle Balance Program DVD’s and will not receive coaching calls. During months 1–6, TECH will use a specially designed smartphone application to monitor dietary intake, body weight, and objectively measured physical activity (obtained from a Blue-tooth enabled accelerometer. STND and SELF will self-monitor on paper diaries. Linear mixed modeling will be used to examine group differences on weight loss at months 3, 6, and 12. Self-monitoring adherence and diet and activity goal attainment will be tested as mediators. Discussion ENGAGED is an innovative weight loss intervention that integrates theory with emerging mobile technologies. We hypothesize that TECH, as compared to STND and SELF, will result in greater weight loss by virtue of improved behavioral adherence and goal achievement. Trial registration NCT01051713

  8. Controlled ecological life support system breadboard project, 1988

    Science.gov (United States)

    Knott, W. M.

    1990-01-01

    The Closed Ecological Life Support System (CELSS) Breadboard Project, NASA's effort to develop the technology required to produce a functioning bioregenerative system, is discussed. The different phases of the project and its current status are described. The relationship between the project components are shown, and major project activities for fiscal years 1989 to 1993 are listed. The Biomass Production Chamber (BPC) became operational and tests of wheat as a single crop are nearing completion.

  9. PERIODIC REVIEW SYSTEM FOR INVENTORY REPLENISHMENT CONTROL FOR A TWO-ECHELON LOGISTICS NETWORK UNDER DEMAND UNCERTAINTY: A TWO-STAGE STOCHASTIC PROGRAMING APPROACH

    Directory of Open Access Journals (Sweden)

    P.S.A. Cunha

    Full Text Available ABSTRACT Here, we propose a novel methodology for replenishment and control systems for inventories of two-echelon logistics networks using a two-stage stochastic programming, considering periodic review and uncertain demands. In addition, to achieve better customer services, we introduce a variable rationing rule to address quantities of the item in short. The devised models are reformulated into their deterministic equivalent, resulting in nonlinear mixed-integer programming models, which are then approximately linearized. To deal with the uncertain nature of the item demand levels, we apply a Monte Carlo simulation-based method to generate finite and discrete sets of scenarios. Moreover, the proposed approach does not require restricted assumptions to the behavior of the probabilistic phenomena, as does several existing methods in the literature. Numerical experiments with the proposed approach for randomly generated instances of the problem show results with errors around 1%.

  10. Explaining worker strain and learning: how important are emotional job demands?

    Science.gov (United States)

    Taris, Toon W; Schreurs, Paul J G

    2009-05-01

    This study examined the added value of emotional job demands in explaining worker well-being, relative to the effects of task characteristics, such as quantitative job demands, job control, and coworker support. Emotional job demands were expected to account for an additional proportion of the variance in well-being. Cross-sectional data were obtained from 11,361 female Dutch home care employees. Hierarchical stepwise regression analysis demonstrated that low control, low support and high quantitative demands were generally associated with lower well-being (as measured in terms of emotional exhaustion, dedication, professional accomplishment and learning). Moreover, high emotional demands were in three out of four cases significantly associated with adverse well-being, in these cases accounting for an additional 1-6% of the variance in the outcome variables. In three out of eight cases the main effects of emotional demands on well-being were qualified by support and control, such that high control and high support either buffered the adverse effects of high emotional demands on well-being or increased the positive effects thereof. All in all, high emotional demands are as important a risk factor for worker well-being as well-established concepts like low job control and high quantitative job demands.

  11. Selective control of attention supports the positivity effect in aging.

    Directory of Open Access Journals (Sweden)

    Laura K Sasse

    Full Text Available There is emerging evidence for a positivity effect in healthy aging, which describes an age-specific increased focus on positive compared to negative information. Life-span researchers have attributed this effect to the selective allocation of cognitive resources in the service of prioritized emotional goals. We explored the basic principles of this assumption by assessing selective attention and memory for visual stimuli, differing in emotional content and self-relevance, in young and old participants. To specifically address the impact of cognitive control, voluntary attentional selection during the presentation of multiple-item displays was analyzed and linked to participants' general ability of cognitive control. Results revealed a positivity effect in older adults' selective attention and memory, which was particularly pronounced for self-relevant stimuli. Focusing on positive and ignoring negative information was most evident in older participants with a generally higher ability to exert top-down control during visual search. Our findings highlight the role of controlled selectivity in the occurrence of a positivity effect in aging. Since the effect has been related to well-being in later life, we suggest that the ability to selectively allocate top-down control might represent a resilience factor for emotional health in aging.

  12. Selective control of attention supports the positivity effect in aging.

    Science.gov (United States)

    Sasse, Laura K; Gamer, Matthias; Büchel, Christian; Brassen, Stefanie

    2014-01-01

    There is emerging evidence for a positivity effect in healthy aging, which describes an age-specific increased focus on positive compared to negative information. Life-span researchers have attributed this effect to the selective allocation of cognitive resources in the service of prioritized emotional goals. We explored the basic principles of this assumption by assessing selective attention and memory for visual stimuli, differing in emotional content and self-relevance, in young and old participants. To specifically address the impact of cognitive control, voluntary attentional selection during the presentation of multiple-item displays was analyzed and linked to participants' general ability of cognitive control. Results revealed a positivity effect in older adults' selective attention and memory, which was particularly pronounced for self-relevant stimuli. Focusing on positive and ignoring negative information was most evident in older participants with a generally higher ability to exert top-down control during visual search. Our findings highlight the role of controlled selectivity in the occurrence of a positivity effect in aging. Since the effect has been related to well-being in later life, we suggest that the ability to selectively allocate top-down control might represent a resilience factor for emotional health in aging.

  13. Predicting changes in sleep complaints from baseline values and changes in work demands, work control, and work preoccupation--the WOLF-project.

    Science.gov (United States)

    Åkerstedt, Torbjörn; Nordin, Maria; Alfredsson, Lars; Westerholm, Peter; Kecklund, Göran

    2012-01-01

    Stress as a cause of disturbed sleep is often taken for granted, but the longitudinal evidence is limited. The aim of this study was to evaluate new cases of poor sleep as a function of changes in reported work demands, work control, and work preoccupation. Longitudinal study of change with measures occurring twice within a 5-year interval during a period when the prevalence of impaired sleep was increasing in Sweden. The sample of companies was taken from northern Sweden (Norrland) and included 3637 individuals from the "WOLF Norrland" longitudinal cohort, collected through company health services. During the measurement period, 16% of those studied developed new cases of impaired sleep. Logistic regressions adjusted for demographics, work environment factors, and disturbed sleep at T1 period one showed a significant increase in new cases for high work demands and high work preoccupation (OR=1.37; Ci=1.09-1.72 and OR=1.80; CI=1.42-2.28, respectively). The analysis of change in the predictors showed effects of a change from low to high work demands (OR=1.39; Ci=1.00-1.95) on new cases of impaired sleep. Consistent high work demands (high at both points) showed a similar increase (OR=1.49; Ci=1.06-2.11) but no effect was seen for reduced demands. Change in work preoccupation yielded stronger effects with OR=2.47 (1.78-2.47) for increased work preoccupation and OR=3.79 (2.70-5.31) for consistent high work preoccupation. Also, a reduction in work preoccupation was associated with a reduction in new cases of disturbed sleep. Control at work was not related to sleep. Stratification with respect to gender mainly led to fewer significant results (particularly for women) due to larger confidence intervals. It was concluded that self-reported work preoccupation predicts subsequent impairment of sleep and that increased preoccupation is associated with new cases of impaired sleep. Similar, but weaker, results were obtained for work demands. Copyright © 2011 Elsevier B

  14. IMPLEMENTATION OF CONTROL CARDS AND SUPPORTING METHOD IN PRODUCTION ENGINEERING

    Directory of Open Access Journals (Sweden)

    Anna WOLNOWSKA

    2012-10-01

    Full Text Available In the article there were presented chosen method associated with statistical control of production processes. Mainly focused on control cards and Pareto‐Lorenz analysis. Showed method were implemented to analysis production process stability of hearing aids in X company (the brand name don’t give because date of production is secret. Researches were made few months after new assembly lines starts‐up. Main aim of researches was defects types identification occurred in production process and determine the scale of effect. Finally received results were satisfactory, i.e. despite of occurred errors, control cards analysis showed that production process of BTE‐type (Behind‐The‐Ear hearing aids was stable.

  15. Integrated Control Strategies Supporting Autonomous Functionalities in Mobile Robots

    Directory of Open Access Journals (Sweden)

    Brandon Sights

    2006-10-01

    Full Text Available High-level intelligence allows a mobile robot to create and interpret complex world models, but without a precise control system, the accuracy of the world model and the robot's ability to interact with its surroundings are greatly diminished. This problem is amplified when the environment is hostile, such as in a battlefield situation where an error in movement or a slow response may lead to destruction of the robot. As the presence of robots on the battlefield continues to escalate and the trend toward relieving the human of the low-level control burden advances, the ability to combine the functionalities of several critical control systems on a single platform becomes imperative.

  16. An integrated supply chain inventory model with imperfect-quality items, controllable lead time and distribution-free demand

    Directory of Open Access Journals (Sweden)

    Lin Hsien-Jen

    2013-01-01

    Full Text Available In this paper, we consider an integrated vendor-buyer inventory policy for a continuous review model with a random number of defective items and screening process gradually at a fixed screening rate in buyer’s arriving order lot. We assume that shortages are allowed and partially backlogged on the buyer’s side, and that the lead time demand distribution is unknown, except its first two moments. The objective is to apply the minmax distribution free approach to determine the optimal order quantity, reorder point, lead time and the number of lots delivered in one production run simultaneously so that the expected total system cost is minimized. Numerical experiments along with sensitivity analysis were performed to illustrate the effects of parameters on the decision and the total system cost.

  17. Three dimensional visualization to support command and control

    International Nuclear Information System (INIS)

    Van Slambrook, G.A.

    1997-04-01

    Virtual reality concepts are changing the way one thinks about and with computers. The concepts have already proven their potential usefulness in a broad range of applications. This research was concerned with exploring and demonstrating the utility of virtual reality in robotics and satellite command and control applications. The robotics work addressed the need to quickly build accurate graphical models of physical environments by allowing a user to interactively build a model of a remote environment by superimposing stereo graphics onto live stereo video. The satellite work addressed the fusion of multiple data sets or models into one synergistic display for more effective training, design, and command and control of satellite systems

  18. Task demand, task management, and teamwork

    Energy Technology Data Exchange (ETDEWEB)

    Braarud, Per Oeivind; Brendryen, Haavar

    2001-03-15

    The current approach to mental workload assessment in process control was evaluated in 3 previous HAMMLAB studies, by analysing the relationship between workload related measures and performance. The results showed that subjective task complexity rating was related to team's control room performance, that mental effort (NASA-TLX) was weakly related to performance, and that overall activity level was unrelated to performance. The results support the argument that general cognitive measures, i.e., mental workload, are weakly related to performance in the process control domain. This implies that other workload concepts than general mental workload are needed for valid assessment of human reliability and for valid assessment of control room configurations. An assessment of task load in process control suggested that how effort is used to handle task demand is more important then the level of effort invested to solve the task. The report suggests two main workload related concepts with a potential as performance predictors in process control: task requirements, and the work style describing how effort is invested to solve the task. The task requirements are seen as composed of individual task demand and team demand. In a similar way work style are seen as composed of individual task management and teamwork style. A framework for the development of the concepts is suggested based on a literature review and experiences from HAMMLAB research. It is suggested that operational definitions of workload concepts should be based on observable control room behaviour, to assure a potential for developing performance-shaping factors. Finally an explorative analysis of teamwork measures and performance in one study indicated that teamwork concepts are related to performance. This lends support to the suggested development of team demand and teamwork style as elements of a framework for the analysis of workload in process control. (Author)

  19. Validity test of the IPD-Work consortium approach for creating comparable job strain groups between Job Content Questionnaire and Demand-Control Questionnaire

    Directory of Open Access Journals (Sweden)

    Bongkyoo Choi

    2015-04-01

    Full Text Available Objectives: This study aims to test the validity of the IPD-Work Consortium approach for creating comparable job strain groups between the Job Content Questionnaire (JCQ and the Demand-Control Questionnaire (DCQ. Material and Methods: A random population sample (N = 682 of all middle-aged Malmö males and females was given a questionnaire with the 14-item JCQ and 11-item DCQ for the job control and job demands. The JCQ job control and job demands scores were calculated in 3 different ways: using the 14-item JCQ standard scale formulas (method 1; dropping 3 job control items and using the 11-item JCQ standard scale formulas with additional scale weights (method 2; and the approach of the IPD Group (method 3, dropping 3 job control items, but using the simple 11-item summation-based scale formulas. The high job strain was defined as a combination of high demands and low control. Results: Between the 2 questionnaires, false negatives for the high job strain were much greater than false positives (37–49% vs. 7–13%. When the method 3 was applied, the sensitivity of the JCQ for the high job strain against the DCQ was lowest (0.51 vs. 0.60–0.63 when the methods 1 and 2 were applied, although the specificity was highest (0.93 vs. 0.87–0.89 when the methods 1 and 2 were applied. The prevalence of the high job strain with the JCQ (the method 3 was applied was considerably lower (4–7% than with the JCQ (the methods 1 and 2 were applied and the DCQ. The number of congruent cases for the high job strain between the 2 questionnaires was smallest when the method 3 was applied. Conclusions: The IPD-Work Consortium approach showed 2 major weaknesses to be used for epidemiological studies on the high job strain and health outcomes as compared to the standard JCQ methods: the greater misclassification of the high job strain and lower prevalence of the high job strain.

  20. Validity test of the IPD-Work consortium approach for creating comparable job strain groups between Job Content Questionnaire and Demand-Control Questionnaire.

    Science.gov (United States)

    Choi, Bongkyoo; Ko, Sangbaek; Ostergren, Per-Olof

    2015-01-01

    This study aims to test the validity of the IPD-Work Consortium approach for creating comparable job strain groups between the Job Content Questionnaire (JCQ) and the Demand-Control Questionnaire (DCQ). A random population sample (N = 682) of all middle-aged Malmö males and females was given a questionnaire with the 14-item JCQ and 11-item DCQ for the job control and job demands. The JCQ job control and job demands scores were calculated in 3 different ways: using the 14-item JCQ standard scale formulas (method 1); dropping 3 job control items and using the 11-item JCQ standard scale formulas with additional scale weights (method 2); and the approach of the IPD Group (method 3), dropping 3 job control items, but using the simple 11-item summation-based scale formulas. The high job strain was defined as a combination of high demands and low control. Between the 2 questionnaires, false negatives for the high job strain were much greater than false positives (37-49% vs. 7-13%). When the method 3 was applied, the sensitivity of the JCQ for the high job strain against the DCQ was lowest (0.51 vs. 0.60-0.63 when the methods 1 and 2 were applied), although the specificity was highest (0.93 vs. 0.87-0.89 when the methods 1 and 2 were applied). The prevalence of the high job strain with the JCQ (the method 3 was applied) was considerably lower (4-7%) than with the JCQ (the methods 1 and 2 were applied) and the DCQ. The number of congruent cases for the high job strain between the 2 questionnaires was smallest when the method 3 was applied. The IPD-Work Consortium approach showed 2 major weaknesses to be used for epidemiological studies on the high job strain and health outcomes as compared to the standard JCQ methods: the greater misclassification of the high job strain and lower prevalence of the high job strain. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  1. When Affect Supports Cognitive Control – A Working Memory Perspective

    Directory of Open Access Journals (Sweden)

    Kolańczyk Alina

    2016-04-01

    Full Text Available The paper delineates a study of executive functions (EFs, construed as procedural working memory (WM, from a motivational perspective. Since WM theories and motivation theories are both concerned with purposive activity, the role of implicit evaluations (affects observed in goal pursuit can be anticipated to arise also in the context of cognitive control, e.g., during the performance of the Stroop task. The role of positive and negative affect in goal pursuit consists in controlling attention resources according to the goal and situational requirements. Positive affect serves to maintain goals and means in the scope of attention (EF1, whereas negative affect activates the inhibition of non-functional contents, e.g., distractors and irrelevant objects (resulting in attention disengagement; EF2. Adaptation to conflict proceeds via sequential triggering of negative and positive affect (EF3. Moreover, it was demonstrated that the focus on action or reflection changes the scope of contents subjected to implicit (affective control. Therefore, I suggest that the motivational system, to a large extent, plays the role of the Central Executive. The paper opens a discussion and proposes studies on affective mechanisms of cognitive control.

  2. Supporting the patient's role in guideline compliance: a controlled study.

    Science.gov (United States)

    Rosenberg, Stephen N; Shnaiden, Tatiana L; Wegh, Arnold A; Juster, Iver A

    2008-11-01

    Clinical messages alerting physicians to gaps in the care of specific patients have been shown to increase compliance with evidence-based guidelines. This study sought to measure any additional impact on compliance when alerting messages also were sent to patients. For alerts that were generated by computerized clinical rules applied to claims, compliance was determined by subsequent claims evidence (eg, that recommended tests were performed). Compliance was measured in the baseline year and the study year for 4 study group employers (combined membership >100,000) that chose to add patient messaging in the study year, and 28 similar control group employers (combined membership >700,000) that maintained physician messaging but did not add patient messaging. The impact of patient messaging was assessed by comparing changes in compliance from baseline to study year in the 2 groups. Multiple logistic regression was used to control for differences between the groups. Because a given member or physician could receive multiple alerts, generalized estimating equations with clustering by patient and physician were used. Controlling for differences in age, sex, and the severity and types of clinical alerts between the study and control groups, the addition of patient messaging increased compliance by 12.5% (P compliance with the evidence-based guidelines underlying the alerts.

  3. Virtual Factory Framework for Supporting Production Planning and Control.

    Science.gov (United States)

    Kibira, Deogratias; Shao, Guodong

    2017-01-01

    Developing optimal production plans for smart manufacturing systems is challenging because shop floor events change dynamically. A virtual factory incorporating engineering tools, simulation, and optimization generates and communicates performance data to guide wise decision making for different control levels. This paper describes such a platform specifically for production planning. We also discuss verification and validation of the constituent models. A case study of a machine shop is used to demonstrate data generation for production planning in a virtual factory.

  4. Spaceport Command and Control System Support Software Development

    Science.gov (United States)

    Brunotte, Leonard

    2016-01-01

    The Spaceport Command and Control System (SCCS) is a project developed and used by NASA at Kennedy Space Center in order to control and monitor the Space Launch System (SLS) at the time of its launch. One integral subteam under SCCS is the one assigned to the development of a data set building application to be used both on the launch pad and in the Launch Control Center (LCC) at the time of launch. This web application was developed in Ruby on Rails, a web framework using the Ruby object-oriented programming language, by a 15 - employee team (approx.). Because this application is such a huge undertaking with many facets and iterations, there were a few areas in which work could be more easily organized and expedited. As an intern working with this team, I was charged with the task of writing web applications that fulfilled this need, creating a virtual and highly customizable whiteboard in order to allow engineers to keep track of build iterations and their status. Additionally, I developed a knowledge capture web application wherein any engineer or contractor within SCCS could ask a question, answer an existing question, or leave a comment on any question or answer, similar to Stack Overflow.

  5. PCI hardware support in LIA-2 control system

    International Nuclear Information System (INIS)

    Bolkhovityanov, D.; Cheblakov, P.

    2012-01-01

    The control system of the LIA-2 accelerator is built on cPCI crates with *86- compatible processor boards running Linux. Slow electronics is connected via CAN-bus, while fast electronics (4 MHz and 200 MHz fast ADCs and 200 MHz timers) are implemented as cPCI/PMC modules. Several ways to drive PCI control electronics in Linux were examined. Finally a user-space drivers approach was chosen. These drivers communicate with hardware via a small kernel module, which provides access to PCI BARs and to interrupt handling. This module was named USPCI (User-Space PCI access). This approach dramatically simplifies creation of drivers, as opposed to kernel drivers, and provides high reliability (because only a tiny and thoroughly-debugged piece of code runs in kernel). LIA-2 accelerator was successfully commissioned, and the solution chosen has proven adequate and very easy to use. Besides, USPCI turned out to be a handy tool for examination and debugging of PCI devices direct from command-line. In this paper available approaches to work with PCI control hardware in Linux are considered, and USPCI architecture is described. (authors)

  6. Real-time adjustment of pressure to demand in water distribution systems: Parameter-less P-controller algorithm

    CSIR Research Space (South Africa)

    Page, Philip R

    2016-08-01

    Full Text Available Remote real-time control is currently the most advanced form of pressure management. Here the parameters describing pressure control valves (or pumps) are changed in real-time in such a way to provide the most optimal pressure in the water...

  7. IT Security Support for the Spaceport Command Control Systems Development Ground Support Development Operations

    Science.gov (United States)

    Branch, Drew A.

    2014-01-01

    Security is one of the most if not the most important areas today. After the several attacks on the United States, security everywhere has heightened from airports to the communication among the military branches legionnaires. With advanced persistent threats (APT's) on the rise following Stuxnet, government branches and agencies are required, more than ever, to follow several standards, policies and procedures to reduce the likelihood of a breach. Attack vectors today are very advanced and are going to continue to get more and more advanced as security controls advance. This creates a need for networks and systems to be in an updated and secured state in a launch control system environment. FISMA is a law that is mandated by the government to follow when government agencies secure networks and devices. My role on this project is to ensure network devices and systems are in compliance with NIST, as outlined in FISMA. I will achieve this by providing assistance with security plan documentation and collection, system hardware and software inventory, malicious code and malware scanning, and configuration of network devices i.e. routers and IDS's/IPS's. In addition, I will be completing security assessments on software and hardware, vulnerability assessments and reporting, and conducting patch management and risk assessments. A guideline that will help with compliance with NIST is the SANS Top 20 Critical Controls. SANS Top 20 Critical Controls as well as numerous security tools, security software and the conduction of research will be used to successfully complete the tasks given to me. This will ensure compliance with FISMA and NIST, secure systems and a secured network. By the end of this project, I hope to have carried out the tasks stated above as well as gain an immense knowledge about compliance, security tools, networks and network devices, as well as policies and procedures.

  8. Significance of family and peer support for metabolic control of type 1 diabetes in adolescents

    Directory of Open Access Journals (Sweden)

    Đurović Dušanka

    2009-01-01

    Full Text Available The aim of the paper was to explore the significance of family and peer support for metabolic control of Type 1 diabetes in adolescents. Metabolic control refers to maintenance of acceptable blood glucose level thus diminishing risk for chronic complications. It involves regular insulin shots, measuring blood glucose and keeping diary, as the daily based self-control. Regular visits to endocrinologist and screening for chronic complications are compulsory. The sample comprised 79 adolescents age 10-17 years with diagnose of Type 1 diabetes and properly treated at the institute. The sample was divided in two groups - with good (N=40 and poor (N=39 metabolic control. A criterium for good metabolic control was glycosilated hemoglobin less than 7,6%. Social support was measured by Social Support Scale consisting of two parts - the first for estimation of registered family support (based upon modified Perceived Social Support Family Scale and the second for estimation of registered friends' support (modified Perceived Social Support Friend Scale. Adolescents with good metabolic control referred statistically more significant social support in the family, unlike the group with poor metabolic control. Considering peer social support, there was no statistically significant difference. Positive family history for diabetes also appeared to be directly linked to good metabolic control.

  9. Job maintenance through Supported Employment PLUS: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Nils-Torge Telle

    2016-09-01

    Full Text Available Sickness absence from work due to experienced distress and mental health issues has continuously increased over the past years in Germany. To investigate how this alarming development can be counteracted, we conducted a randomized controlled trial evaluating a job coaching intervention to maintain the working capacity of members of staff and ultimately prevent sickness absence. Our sample included N = 99 employees who reported mental distress due to work-related problems. The intervention group (n = 58 received between 8 and 12 individual job coaching sessions in which they worked with a professional job coach to reduce their mental distress. The control group (n = 41 received a brochure about mental distress. Data were collected before the start of the study, at the end of the job coaching intervention and at a 3-month follow up. These data included the number of sickness absence days as the primary outcome and questionnaire measures to assess burnout indicators, life satisfaction and work-related experiences and behaviors. Compared with the control group, the results indicated no reduction in sickness absence in the intervention group but fewer depressive symptoms, a heightened ability of the participants to distance themselves from work, more experience of work-related success, less depletion of emotional resources and a greater satisfaction with life when participants had received the job coaching. Thus, although we could not detect a reduction in sickness absence between the groups, job coaching was shown to be a viable intervention technique to benefit employees by contributing to re-establish their mental health. We discuss the implications of the study and outline future research.

  10. Job Maintenance through Supported Employment PLUS: A Randomized Controlled Trial.

    Science.gov (United States)

    Telle, Nils-Torge; Moock, Jörn; Heuchert, Sandra; Schulte, Vivian; Rössler, Wulf; Kawohl, Wolfram

    2016-01-01

    Sickness absence from work due to experienced distress and mental health issues has continuously increased over the past years in Germany. To investigate how this alarming development can be counteracted, we conducted a randomized controlled trial evaluating a job coaching intervention to maintain the working capacity of members of staff and ultimately prevent sickness absence. Our sample included N  = 99 employees who reported mental distress due to work-related problems. The intervention group ( n  = 58) received between 8 and 12 individual job coaching sessions in which they worked with a professional job coach to reduce their mental distress. The control group ( n  = 41) received a brochure about mental distress. Data were collected before the start of the study, at the end of the job coaching intervention, and at a 3-month follow-up. These data included the number of sickness absence days as the primary outcome and questionnaire measures to assess burnout indicators, life satisfaction, and work-related experiences and behaviors. Compared with the control group, the results indicated no reduction in sickness absence in the intervention group but fewer depressive symptoms, a heightened ability of the participants to distance themselves from work, more experience of work-related success, less depletion of emotional resources, and a greater satisfaction with life when participants had received the job coaching. Thus, although we could not detect a reduction in sickness absence between the groups, job coaching was shown to be a viable intervention technique to benefit employees by contributing to re-establish their mental health. We discuss the implications of the study and outline future research.

  11. Novel demands on the professionals – how internationalization may be a path to support the development of professional reflectivity and professional imagination

    DEFF Research Database (Denmark)

    Eriksen, Kathrine Krageskov

    Currently new demands on the (health) professionals may be identified following massive changes to both their work and societal role. Increased use of technological solutions including tele-medicine and ambient assisted living technology; a strengthened focus on inter-professional and cross-secto...... and teachers with possibilities to experience different approaches across countries to both education and the professional practice – and internationalization of education may hence be perceived as a “short-cut” for stimulating especially the development of professional imagination....

  12. Demand for and availability of online support to stop smoking Soporte en línea para parar de fumar Suporte online para parar de fumar

    Directory of Open Access Journals (Sweden)

    Beatriz Helena Carlini

    2012-12-01

    Full Text Available OBJECTIVES: Estimate the frequency of online searches on the topic of smoking and analyze the quality of online resources available to smokers interested in giving up smoking. METHODS: Search engines were used to revise searches and online resources related to stopping smoking in Brazil in 2010. The number of searches was determined using analytical tools available on Google Ads; the number and type of sites were determined by replicating the search patterns of internet users. The sites were classified according to content (advertising, library of articles and other. The quality of the sites was analyzed using the Smoking Treatment Scale- Content (STS-C and the Smoking Treatment Scale - Rating (STS-R. RESULTS: A total of 642,446 searches was carried out. Around a third of the 113 sites encountered were of the 'library' type, i.e. they only contained articles, followed by sites containing clinical advertising (18.6 and professional education (10.6. Thirteen of the sites offered advice on quitting directed at smokers. The majority of the sites did not contain evidence-based information, were not interactive and did not have the possibility of communicating with users after the first contact. Other limitations we came across were a lack of financial disclosure as well as no guarantee of privacy concerning information obtained and no distinction made between editorial content and advertisements. CONCLUSIONS: There is a disparity between the high demand for online support in giving up smoking and the scarcity of quality online resources for smokers. It is necessary to develop interactive, customized online resources based on evidence and random clinical testing in order to improve the support available to Brazilian smokers.OBJETIVO: Estimar la frecuencia de búsquedas en línea sobre tabaquismo y analizar la calidad de los recursos en línea de apoyo para fumadores interesados en parar de fumar. MÉTODOS: Revisión de búsquedas y recursos en l

  13. Subgenual Cingulum Microstructure Supports Control of Emotional Conflict

    Science.gov (United States)

    Keedwell, Paul A.; Doidge, Amie N.; Meyer, Marcel; Lawrence, Natalia; Lawrence, Andrew D.; Jones, Derek K.

    2016-01-01

    Major depressive disorder (MDD) is associated with specific difficulties in attentional disengagement from negatively valenced material. Diffusion MRI studies have demonstrated altered white matter microstructure in the subgenual cingulum bundle (CB) in individuals with MDD, though the functional significance of these alterations has not been examined formally. This study explored whether individual differences in selective attention to negatively valenced stimuli are related to interindividual differences in subgenual CB microstructure. Forty-six individuals (21 with remitted MDD, 25 never depressed) completed an emotional Stroop task, using happy and angry distractor faces overlaid by pleasant or unpleasant target words and a control gender-based Stroop task. CBs were reconstructed in 38 individuals using diffusion-weighted imaging and tractography, and mean fractional anisotropy (FA) computed for the subgenual, retrosplenial, and parahippocampal subdivisions. No significant correlations were found between FA and performance in the control gender-based Stroop task in any CB region. However, the degree of interference produced by angry face distractors on time to identify pleasant words (emotional conflict) correlated selectively with FA in the subgenual CB (r = −0.53; P = 0.01). Higher FA was associated with reduced interference, irrespective of a diagnosis of MDD, suggesting that subgenual CB microstructure is functionally relevant for regulating attentional bias toward negative interpersonal stimuli. PMID:27048427

  14. Subgenual Cingulum Microstructure Supports Control of Emotional Conflict.

    Science.gov (United States)

    Keedwell, Paul A; Doidge, Amie N; Meyer, Marcel; Lawrence, Natalia; Lawrence, Andrew D; Jones, Derek K

    2016-06-01

    Major depressive disorder (MDD) is associated with specific difficulties in attentional disengagement from negatively valenced material. Diffusion MRI studies have demonstrated altered white matter microstructure in the subgenual cingulum bundle (CB) in individuals with MDD, though the functional significance of these alterations has not been examined formally. This study explored whether individual differences in selective attention to negatively valenced stimuli are related to interindividual differences in subgenual CB microstructure. Forty-six individuals (21 with remitted MDD, 25 never depressed) completed an emotional Stroop task, using happy and angry distractor faces overlaid by pleasant or unpleasant target words and a control gender-based Stroop task. CBs were reconstructed in 38 individuals using diffusion-weighted imaging and tractography, and mean fractional anisotropy (FA) computed for the subgenual, retrosplenial, and parahippocampal subdivisions. No significant correlations were found between FA and performance in the control gender-based Stroop task in any CB region. However, the degree of interference produced by angry face distractors on time to identify pleasant words (emotional conflict) correlated selectively with FA in the subgenual CB (r = -0.53; P = 0.01). Higher FA was associated with reduced interference, irrespective of a diagnosis of MDD, suggesting that subgenual CB microstructure is functionally relevant for regulating attentional bias toward negative interpersonal stimuli. © The Author 2016. Published by Oxford University Press.

  15. Distributed Medium Access Control with SDMA Support for WLANs

    Science.gov (United States)

    Zhou, Sheng; Niu, Zhisheng

    With simultaneous multi-user transmissions, spatial division multiple access (SDMA) provides substantial throughput gain over the single user transmission. However, its implementation in WLANs with contention-based IEEE 802.11 MAC remains challenging. Problems such as coordinating and synchronizing the multiple users need to be solved in a distributed way. In this paper, we propose a distributed MAC protocol for WLANs with SDMA support. A dual-mode CTS responding mechanism is designed to accomplish the channel estimation and user synchronization required for SDMA. We analytically study the throughput performance of the proposed MAC, and dynamic parameter adjustment is designed to enhance the protocol efficiency. In addition, the proposed MAC protocol does not rely on specific physical layer realizations, and can work on legacy IEEE 802.11 equipment with slight software updates. Simulation results show that the proposed MAC outperforms IEEE 802.11 significantly, and that the dynamic parameter adjustment can effectively track the load variation in the network.

  16. An experimental study of the job demand-control model with measures of heart rate variability and salivary alpha-amylase: Evidence of increased stress responses to increased break autonomy.

    Science.gov (United States)

    O'Donnell, Emma; Landolt, Kathleen; Hazi, Agnes; Dragano, Nico; Wright, Bradley J

    2015-01-01

    We assessed in an experimental design whether the stress response towards a work task was moderated by the autonomy to choose a break during the assigned time to complete the task. This setting is defined in accordance with the theoretical framework of the job-demand-control (JDC) model of work related stress. The findings from naturalistic investigations of a stress-buffering effect of autonomy (or 'buffer hypothesis') are equivocal and the experimental evidence is limited, especially with relation to physiological indices of stress. Our objective was to investigate if increased autonomy in a particular domain (break time control) was related with adaptive physiology using objective physiological markers of stress; heart rate variability (HRV) and salivary alpha amylase (sAA). We used a within-subject design and the 60 female participants were randomly assigned to an autonomy (free timing of break) and standard conditions (fixed timing of break) of a word processing task in a simulated office environment in a random order. Participants reported increased perceptions of autonomy, no difference in demand and performed worse in the task in the break-time autonomy versus the standard condition. The results revealed support for the manipulation of increased autonomy, but in the opposing direction. Increased autonomy was related with dysregulated physiological reactivity, synonymous with typical increased stress responses. Potentially, our findings may indicate that autonomy is not necessary a resource but could become an additional stressor when it adds additional complexity while the amount of work (demands) remains unchanged. Further, our findings underscore the need to collect objective physiological evidence of stress to supplement self-reported information. Self-report biases may partially explain the inconsistent findings with the buffer hypothesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Parental Perceived Control and Social Support: Linkages to Change in Parenting Behaviors During Early Adolescence.

    Science.gov (United States)

    Lippold, Melissa A; Glatz, Terese; Fosco, Gregory M; Feinberg, Mark E

    2018-06-01

    Prior studies have found that parents' perceptions of control over their lives and their social support may both be important for parenting behaviors. Yet, few studies have examined their unique and interacting influence on parenting behaviors during early adolescence. This longitudinal study of rural parents in two-parent families (N = 636) investigated (a) whether perceived control and social support when their youth were in sixth grade were independently or interactively associated with changes in parenting behaviors (discipline, standard setting) and parent-child warmth and hostility 6 months later and (b) if these linkages differed by parent gender. We also investigated the interactive links between perceived control, social support, and parenting. Specifically, we tested if parents' perceived control moderated the linkages between social support and parenting and if these linkages differed by parent gender. Greater perceived control predicted more increases in parents' consistent discipline and standard setting, whereas greater social support predicted increases in parent-child warmth and decreases in parent-child hostility. Parental perceived control moderated the effect of social support on parental warmth: For mothers only, social support was significantly linked to parent-child warmth only when mothers had low (but not high) perceived self-control. The discussion focuses on reasons why perceived control and social support may have associations with different aspects of parenting and why these might differ for mothers and fathers. © 2017 Family Process Institute.

  18. Selected Aircraft Throttle Controller With Support Of Fuzzy Expert Inference System

    Directory of Open Access Journals (Sweden)

    Żurek Józef

    2014-12-01

    Full Text Available The paper describes Zlin 143Lsi aircraft engine work parameters control support method – hourly fuel flow as a main factor under consideration. The method concerns project of aircraft throttle control support system with use of fuzzy logic (fuzzy inference. The primary purpose of the system is aircraft performance optimization, reducing flight cost at the same time and support proper aircraft engine maintenance. Matlab Software and Fuzzy Logic Toolbox were used in the project. Work of the system is presented with use of twenty test samples, five of them are presented graphically. In addition, system control surface, included in the paper, supports system all work range analysis.

  19. Demand Response as a System Reliability Resource

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Lewis, Nancy Jo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Watson, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Auslander, David [Univ. of California, Berkeley, CA (United States); Paprotny, Igor [Univ. of California, Berkeley, CA (United States); Makarov, Yuri [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-12-31

    The Demand Response as a System Reliability Resource project consists of six technical tasks: • Task 2.1. Test Plan and Conduct Tests: Contingency Reserves Demand Response (DR) Demonstration—a pioneering demonstration of how existing utility load-management assets can provide an important electricity system reliability resource known as contingency reserve. • Task 2.2. Participation in Electric Power Research Institute (EPRI) IntelliGrid—technical assistance to the EPRI IntelliGrid team in developing use cases and other high-level requirements for the architecture. • Task 2.3. Research, Development, and Demonstration (RD&D) Planning for Demand Response Technology Development—technical support to the Public Interest Energy Research (PIER) Program on five topics: Sub-task 1. PIER Smart Grid RD&D Planning Document; Sub-task 2. System Dynamics of Programmable Controllable Thermostats; Sub-task 3. California Independent System Operator (California ISO) DR Use Cases; Sub-task 4. California ISO Telemetry Requirements; and Sub-task 5. Design of a Building Load Data Storage Platform. • Task 2.4. Time Value of Demand Response—research that will enable California ISO to take better account of the speed of the resources that it deploys to ensure compliance with reliability rules for frequency control. • Task 2.5. System Integration and Market Research: Southern California Edison (SCE)—research and technical support for efforts led by SCE to conduct demand response pilot demonstrations to provide a contingency reserve service (known as non-spinning reserve) through a targeted sub-population of aggregated residential and small commercial customers enrolled in SCE’s traditional air conditioning (AC) load cycling program, the Summer Discount Plan. • Task 2.6. Demonstrate Demand Response Technologies: Pacific Gas and Electric (PG&E)—research and technical support for efforts led by PG&E to conduct a demand response pilot demonstration to provide non

  20. Technical support for digital systems technology development. Task order 1: ISP contention analysis and control

    Science.gov (United States)

    Stehle, Roy H.; Ogier, Richard G.

    1993-01-01

    Alternatives for realizing a packet-based network switch for use on a frequency division multiple access/time division multiplexed (FDMA/TDM) geostationary communication satellite were investigated. Each of the eight downlink beams supports eight directed dwells. The design needed to accommodate multicast packets with very low probability of loss due to contention. Three switch architectures were designed and analyzed. An output-queued, shared bus system yielded a functionally simple system, utilizing a first-in, first-out (FIFO) memory per downlink dwell, but at the expense of a large total memory requirement. A shared memory architecture offered the most efficiency in memory requirements, requiring about half the memory of the shared bus design. The processing requirement for the shared-memory system adds system complexity that may offset the benefits of the smaller memory. An alternative design using a shared memory buffer per downlink beam decreases circuit complexity through a distributed design, and requires at most 1000 packets of memory more than the completely shared memory design. Modifications to the basic packet switch designs were proposed to accommodate circuit-switched traffic, which must be served on a periodic basis with minimal delay. Methods for dynamically controlling the downlink dwell lengths were developed and analyzed. These methods adapt quickly to changing traffic demands, and do not add significant complexity or cost to the satellite and ground station designs. Methods for reducing the memory requirement by not requiring the satellite to store full packets were also proposed and analyzed. In addition, optimal packet and dwell lengths were computed as functions of memory size for the three switch architectures.