WorldWideScience

Sample records for demands control support

  1. Demands, control, and support: a meta-analytic review of work characteristics interrelationships.

    Science.gov (United States)

    Luchman, Joseph N; González-Morales, M Gloria

    2013-01-01

    The job demands-control-support model (DCS; Karasek, 1979) is an influential theory for understanding how work characteristics relate to employee well-being, health, and performance. However, previous research has largely neglected theory-building regarding the interrelationships between job demands, control, and support. We remedy such theoretical underdevelopment by reviewing and integrating theory on the relationships between demands, control, and support to develop five hypotheses. We test our hypotheses within a meta-analytic framework using a set of 106 studies. Our results show negative demands-supervisor support and demands-coworker support relationships, but no significant demand-control relationship. Our findings also indicate positive control-supervisor support and control-coworker support relationships. Using the meta-analytic effect sizes, we also estimate two competing structural equation models intended to discern which theoretical model using DCS work characteristics to predict occupational strain and well-being is more consistent with our data. Our results suggest that job control and both sources of social support should be treated independently, as opposed to indicators of a shared latent factor, in terms of their prediction of well-being and job demands. Our study offers support for the usefulness of the DCS and more modern conceptualizations of the working environment in understanding the employee work experience and for predicting important work outcomes. (

  2. 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.

  3. Reciprocal Relations among Job Demands, Job Control, and Social Support Are Moderated by Neuroticism: A Cross-Lagged Analysis

    Science.gov (United States)

    Cieslak, Roman; Knoll, Nina; Luszczynska, Aleksandra

    2007-01-01

    This study investigated whether neuroticism moderates the relations among social support (from coworkers and supervisors) and work strain characteristics (i.e. job demands and job control). A full cross-lagged panel analysis was used to test whether social support predicts job demands and control or whether job demands and job control predict…

  4. 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 l

  5. 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…

  6. 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.

  7. 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

  8. 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...

  9. Sleep Quality Among Latino Farmworkers in North Carolina: Examination of the Job Control-Demand-Support Model.

    Science.gov (United States)

    Sandberg, Joanne C; Nguyen, Ha T; Quandt, Sara A; Chen, Haiying; Summers, Phillip; Walker, Francis O; Arcury, Thomas A

    2016-06-01

    Sleep problems are associated with physical and mental health disorders and place individuals at an increased risk of workplace injuries. The demand-control-support model posits that job demands and the capacity to control work processes influence workers' level of distress, thereby affecting their physical and mental health; supervisor support can buffer the negative effect of high demands and low control. Data on the sleep quality and the organization of work of Latino men were collected in agricultural areas in North Carolina in 2012. 147 Mexican-born farmworkers ages 30 and older, most of whom had H-2A visas, provided information about sleep quality and organization of work. Most (83 %) farmworkers reported good sleep quality. The association between working more than 40 h per week and reporting poor sleep quality approached statistical significance. Additional research is needed to understand whether job demands, job control, and social support affect farmworkers' sleep quality.

  10. 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.

  11. 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) j

  12. 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)

  13. The relationship of the job demands-control-support model with vigor across time: testing for reciprocality.

    Science.gov (United States)

    Armon, Galit; Shmuel, Samuel; Shirom, Arie

    2012-11-01

    We used a longitudinal design to investigate the hypotheses that the components of the Job Demands-Control-Support model and changes in their levels over time predict subsequent changes in levels of positive affect of vigor over time, and vice versa. Our study was conducted on a sample of adults working in a variety of occupations (N = 909, 68% men) at three points in time (T1, T2, and T3), over a period of about four years, controlling for neuroticism and other potential confounding variables. Job control at T1 and increase in its levels from T1 to T2 predicted an increase from T2 to T3 in the levels of vigor, whereas for social support, only its level at T1 predicted an increase from T2 to T3 in levels of vigor. An increase from T1 to T2 in levels of job demands predicted an increase from T2 to T3 in levels of vigor only for those rated low on neuroticism. Vigor at T1 predicted an increase from T2 to T3 in levels of job control and social support, but not changes from T2 to T3 in levels of job demands. The reciprocal causal relationship between job resources and vigor exists regardless of the demands of the work environment.

  14. 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.

  15. 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.

  16. 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

    2017-08-01

    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.

  17. 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

  18. Evolvable work-centred support systems for command and control: creating systems users can adapt to meet changing demands.

    Science.gov (United States)

    Roth, E; Scott, R; Deutsch, S; Kuper, S; Schmidt, V; Stilson, M; Wampler, J

    2006-06-10

    Military command and control (C2) organizations are complex socio-technical systems which must constantly adapt to meet changing operational requirements. We describe our experiences in developing a work-centred support system (WCSS) to aid weather forecasting and monitoring in a military airlift C2 organization as an illustrative case. As part of the development process we conducted field observations both before and after introduction of the WCSS in their operations centre. A striking finding was the constant changes that operations personnel faced (changes in goals and priorities, changes in scale of operations, changes in team roles and structure, and changes in information sources and systems). We describe the changes in workplace demands that we observed and the modifications we needed to make to the WCSS in response. For today's fielded systems, it is seldom possible to make changes that are responsive to users' changing requirements in a timely manner. We argue for the need to incorporate facilities that enable users to adapt their systems to the changing requirements of work and point to some promising directions towards evolvable work-centred support systems.

  19. Co-effect of Demand-control-support Model and Effort-reward Imbalance Model on Depression Risk Estimation in Humans:Findings from Henan Province of China

    Institute of Scientific and Technical Information of China (English)

    YU Shan Fa; NAKATA Akinori; GU Gui Zhen; SWANSON Naomi G; ZHOU Wen Hui; HE Li Hua; WANG Sheng

    2013-01-01

    Objective To investigate the co-effect of Demand-control-support (DCS) model and Effort-reward Imbalance (ERI) model on the risk estimation of depression in humans in comparison with the effects when they are used respectively. Methods A total of 3 632 males and 1 706 females from 13 factories and companies in Henan province were recruited in this cross-sectional study. Perceived job stress was evaluated with the Job Content Questionnaire and Effort-Reward Imbalance Questionnaire (Chinese version). Depressive symptoms were assessed by using the Center for Epidemiological Studies Depression Scale (CES-D). Results DC (demands/job control ratio) and ERI were shown to be independently associated with depressive symptoms. The outcome of low social support and overcommitment were similar. High DC and low social support (SS), high ERI and high overcommitment, and high DC and high ERI posed greater risks of depressive symptoms than each of them did alone. ERI model and SS model seem to be effective in estimating the risk of depressive symptoms if they are used respectively. Conclusion The DC had better performance when it was used in combination with low SS. The effect on physical demands was better than on psychological demands. The combination of DCS and ERI models could improve the risk estimate of depressive symptoms in humans.

  20. Upper-limb motor control in patients after stroke: Attentional demands and the potential beneficial effects of arm support

    NARCIS (Netherlands)

    Houwink, A.; Steenbergen, B.; Prange, G.B.; Buurke, J.H.; Geurts, A.C.H.

    2013-01-01

    The goal of this study was to investigate the attentional load of using the upper limb in moderately and mildly affected patients after stroke, with and without arm support. Ten patients with stroke (4 mild and 6 moderate paresis) and ten healthy, gender- and age-matched control subjects performed a

  1. Upper-limb motor control in patients after stroke: Attentional demands and the potential beneficial effects of arm support.

    NARCIS (Netherlands)

    Houwink, A.; Steenbergen, B.; Prange, G.B.; Buurke, J.H.; Geurts, A.C.H.

    2013-01-01

    The goal of this study was to investigate the attentional load of using the upper limb in moderately and mildly affected patients after stroke, with and without arm support. Ten patients with stroke (4 mild and 6 moderate paresis) and ten healthy, gender- and age-matched control subjects performed a

  2. Voltage Controlled Dynamic Demand Response

    DEFF Research Database (Denmark)

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

    2013-01-01

    . 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...

  3. 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...

  4. 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.

  5. 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)

  6. 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

  7. DEMAND CATEGORISATION, FORECASTING, AND INVENTORY CONTROL FOR INTERMITTENT DEMAND ITEMS

    Directory of Open Access Journals (Sweden)

    E. Babiloni

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: It is commonly assumed that intermittent demand appears randomly, with many periods without demand; but that when it does appear, it tends to be higher than unit size. Basic and well-known forecasting techniques and stock policies perform very poorly with intermittent demand, making new approaches necessary. To select the appropriate inventory management policy, it is important to understand the demand pattern for the items, especially when demand is intermittent. The use of a forecasting method designed for an intermittent demand pattern, such as Croston’s method, is required instead of a simpler and more common approach such as exponential smoothing. The starting point is to establish taxonomic rules to select efficiently the most appropriate forecasting and stock control policy to cope with thousands of items found in real environments. This paper contributes to the state of the art in: (i categorisation of the demand pattern; (ii methods to forecast intermittent demand; and (iii stock control methods for items with intermittent demand patterns. The paper first presents a structured literature review to introduce managers to the theoretical research about how to deal with intermittent demand items in both forecasting and stock control methods, and then it points out some research gaps for future development for the three topics.

    AFRIKAANSE OPSOMMING: Daar word algemeen aanvaar dat intermitterende vraag op toevalswyse voorkom, met verskeie periodes waar daar geen vraag is nie. Wanneer die vraag dan wel materialiseer, oorskry dit dikwels die eenheidsgrootte. Die bekende vooruitskattingstegnieke en voorraadbeleidstellings het min sukses waar intermitterende vraag voorkom, sodat nuwe benaderings nodig is om die problem aan te spreek. Om ‘n geskikte voorraadbestuur-beleid te selekteer, is dit noodsaaklik om die vraagpatroon van die items te verstaan, juis in gevalle van intermitterende patrone. Die gebruik van

  8. Psychosocial working conditions and self-reported health in a representative sample of wage-earners: a test of the different hypotheses of the Demand-Control-Support-Model.

    Science.gov (United States)

    Vanroelen, Christophe; Levecque, Katia; Louckx, Fred

    2009-02-01

    This paper presents an in-depth examination of the demand-control-support-model (DCS-model). Each hypothesis of the DCS-model is tested: the main effects of job demands, job autonomy, task variation and social support; the additive effects of job strain, active learning and iso-strain; and the interactive buffer-effects of job autonomy, task variation and support on job demands. Data from a representative cross-sectional sample of 11,099 male and female wage-earners are investigated using log linear methods. The outcome measures are self-reported persistent fatigue, musculoskeletal complaints and emotional well-being. There is some support for each of the hypotheses. Quantitative job demands and superior support have the strongest effects. The job autonomy and buffer hypotheses are only partially supported. The strong effects of job demands, support, job strain and active learning are suggesting that a policy aimed at improving psychosocial working conditions should focus on a bearable level of job demands and the quality of social relationships at work.

  9. Indirect control of flexible demand for power system applications

    DEFF Research Database (Denmark)

    Sossan, Fabrizio

    demand is addressed. We investigate the subject considering both how to achieve a shift in the consumption of the single DSRs, and how to generate the indirect control signal for a population of DSRs in order to support the operation of the grid. In the former case, we develop algorithms that achieve...... 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...... Flexhouse, a facility of DTU Elektro for testing demand side management strategies, as experimental site. In the latter case, we develop four applications where flexible demand is required to support power system operations. The applications are: integration of the operation of flexible demand...

  10. 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 elde

  11. Wireless Demand Response Controls for HVAC Systems

    Energy Technology Data Exchange (ETDEWEB)

    Federspiel, Clifford

    2009-06-30

    The objectives of this scoping study were to develop and test control software and wireless hardware that could enable closed-loop, zone-temperature-based demand response in buildings that have either pneumatic controls or legacy digital controls that cannot be used as part of a demand response automation system. We designed a SOAP client that is compatible with the Demand Response Automation Server (DRAS) being used by the IOUs in California for their CPP program, design the DR control software, investigated the use of cellular routers for connecting to the DRAS, and tested the wireless DR system with an emulator running a calibrated model of a working building. The results show that the wireless DR system can shed approximately 1.5 Watts per design CFM on the design day in a hot, inland climate in California while keeping temperatures within the limits of ASHRAE Standard 55: Thermal Environmental Conditions for Human Occupancy.

  12. DEMAND CONTROLLED VENTILATION AND CLASSROOM VENTILATION

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J.; Mendell, Mark J.; Davies, Molly; Eliseeva, Ekaterina; Faulkner, David; Hong, Tienzen; Sullivan, Douglas P.

    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. Major findings included: ? The single-location carbon dioxide sensors widely used for demand controlled ventilation frequently have large errors and will fail to effectively control ventilation rates (VRs).? Multi-location carbon dioxide measurement systems with more expensive sensors connected to multi-location sampling systems may measure carbon dioxide more accurately.? Currently-available optical people counting systems work well much of the time but have large counting errors in some situations. ? In meeting rooms, measurements of carbon dioxide at return-air grilles appear to be a better choice than wall-mounted sensors.? In California, demand controlled ventilation in general office spaces is projected to save significant energy and be cost effective only if typical VRs without demand controlled ventilation are very high relative to VRs in codes. Based on the research, several recommendations were developed for demand controlled ventilation specifications in the California Title 24 Building Energy Efficiency Standards.The research on classroom ventilation collected data over two years on California elementary school classrooms to investigate associations between VRs and student illness absence (IA). Major findings included: ? Median classroom VRs in all studied climate zones were below the California guideline, and 40percent lower in portable than permanent buildings.? Overall, one additional L/s per person of VR was associated with 1.6percent less IA. ? Increasing average VRs in California K-12 classrooms from the current average to the required level is estimated to decrease IA by 3.4percent, increasing State attendance-based funding to school districts by $33M, with $6.2 M in increased energy costs. Further VR increases would provide additional benefits

  13. Demand Response on domestic thermostatically controlled loads

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam

    . 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......, with respect to different power reduction levels, are analysed. Finally, the impact of demand response activation on the TCLs aggregated power is studied in terms of error in power limit, ramping rates and peak overshoot in different control scenarios. Lastly, the advantage and disadvantage of the different...

  14. The Demand-Control Model: Specific demands, specific Control, and well-defined groups

    NARCIS (Netherlands)

    Jonge, J. de; Dollard, M.F.; Dormann, C.; Blanc, P.M.; Houtman, I.L.D.

    2000-01-01

    The purpose of this study was to test the Demand-Control Model (DCM), accompanied by three goals. Firstly, we used alternative, more focused, and multifaceted measures of both job demands and job control that are relevant and applicable to today's working contexts. Secondly, this study intended to

  15. Demand as frequency-controlled reserve

    Energy Technology Data Exchange (ETDEWEB)

    Bang, C.; Togeby, M.; Holmboe, N.M.; Brus, R. [Ea Energianalyse A/S, Copenhagen (Denmark); Brandt Rasmussen, C.; Oestergaard, J.; Douglas, P.J. [DTU CEE, Kgs. Lyngby (Denmark); Lund Nielsen, K. [Danfoss, Nordborg (Denmark); Gorzelak, L. [Vestfrost, Esbjerg (Denmark); Rolsted Mattesen, M. [Oestkraft, Roenne (Denmark)

    2013-05-15

    The project is based upon active control of electricity demand as function of grid frequency. Data have been collected from domestic households and industrial loads covering i.e. circulation pumps, electrical domestic heating, bottle coolers, a wastewater treatment plant etc. A special electronic device, referred to as the ''SmartBox'', has been developed during the project. The SmartBox has the ability to control a connected load by either on/off (shutting down the mains for the appliance) or by altering the temperature set-point digitally for a thermostat. The box measure all relevant data from the attached demand and sends the data by mobile network to a central server. The SmartBox is configurable from a website where it is possible to i.e.: upload new firmware for the devices, configure of various parameters and access measurement data. The practical demonstration has included data from about: 1) 50 pcs. Carlsberg Vestfrost bottle coolers (control by thermostat). 2) 20 pcs. Danfoss DEVI electrical domestic heating (control by thermostat). 3) 20 pcs. Bornholm Forsyning water purifying plant (control by SCADA). 4) 30 pcs. Various on/off controlling circulation pumps, dehumidifiers, freezers, heaters etc. Electronic Housekeeper, a consumer product was installed in domestic households connected to i.e. freezers, refrigerators and electrical heating. The product included all necessary hardware to control the attached appliance as function of frequency. The product was customized to deliver data for the project as well. Basically all tests has shown, that it is possible the postpone electricity demands as a function of frequency and thereby help maintaining the system balance. The flexibility depends on the size of the actual consumption and its capacity. By the capacity means the interaction of factors as: how fast the demand reacts, the probability that it reacts and the timespan of the possible reaction. (Author)

  16. 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...

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. Using Bayesian networks to analyze occupational stress caused by work demands: preventing stress through social support.

    Science.gov (United States)

    García-Herrero, Susana; Mariscal, M A; Gutiérrez, J M; Ritzel, Dale O

    2013-08-01

    Occupational stress is a major health hazard and a serious challenge to the effective operation of any company and represents a major problem for both individuals and organizations. Previous researches have shown that high demands (e.g. workload, emotional) combined with low resources (e.g. support, control, rewards) are associated with adverse health (e.g. psychological, physical) and organizational impacts (e.g. reduced job satisfaction, sickness absence). The objective of the present work is to create a model to analyze how social support reduces the occupational stress caused by work demands. This study used existing Spanish national data on working conditions collected by the Spanish Ministry of Labour and Immigration in 2007, where 11,054 workers were interviewed by questionnaire. A probabilistic model was built using Bayesian networks to explain the relationships between work demands and occupational stress. The model also explains how social support contributes positively to reducing stress levels. The variables studied were intellectually demanding work, overwork, workday, stress, and social support. The results show the importance of social support and of receiving help from supervisors and co-workers in preventing occupational stress. The study provides a new methodology that explains and quantifies the effects of intellectually demanding work, overwork, and workday in occupational stress. Also, the study quantifies the importance of social support to reduce occupational stress.

  2. 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.

  3. 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...

  4. Job stress across gender: the importance of emotional and intellectual demands and social support in women.

    Science.gov (United States)

    Rivera-Torres, Pilar; Araque-Padilla, Rafael Angel; Montero-Simó, María José

    2013-01-14

    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. 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.

  6. Controlling Energy Demand in Mobile Computing Systems

    CERN Document Server

    Ellis, Carla

    2007-01-01

    This lecture provides an introduction to the problem of managing the energy demand of mobile devices. Reducing energy consumption, primarily with the goal of extending the lifetime of battery-powered devices, has emerged as a fundamental challenge in mobile computing and wireless communication. The focus of this lecture is on a systems approach where software techniques exploit state-of-the-art architectural features rather than relying only upon advances in lower-power circuitry or the slow improvements in battery technology to solve the problem. Fortunately, there are many opportunities to i

  7. 工作需求控制支持压力模型及实证研究评析%The Job Demand-Control-Support Model:A Review of Empirical Research

    Institute of Scientific and Technical Information of China (English)

    史茜; 舒晓兵; 罗玉越

    2010-01-01

    工作需求控制支持(The job demand-control-support,JDCS)模型在工作压力研究领域是一个影响广泛的组织压力模型,根据对于JDCS模型近30年的实证研究进行了综合和分析,并从模型的适用性研究状况、模型的相关研究变量的探索、模型的发展三个方面进行了总结,发现目前的JDCS模型的相关实证反映出其具有很好的解释力和适用性,但是模型本身及根据模型开发的JCQ量表都需要后续研究的不断完善和发展.

  8. Job Strain and Self-Reported Insomnia Symptoms among Nurses: What about the Influence of Emotional Demands and Social Support?

    Science.gov (United States)

    Portela, Luciana Fernandes; Kröning Luna, Caroline; Rotenberg, Lúcia; Silva-Costa, Aline; Toivanen, Susanna; Araújo, Tania; Griep, Rosane Härter

    2015-01-01

    Job strain, derived from high psychological demands and low job control, is associated with insomnia, but information on the role of emotional demands and social support in this relationship is scarce. The aims of this study were (i) to test the association between job strain and self-reported insomnia symptoms, (ii) to evaluate the combination of emotional demands and job control regarding insomnia symptoms, and (iii) to analyze the influence of social support in these relationships. This cross-sectional study refers to a sample of nurses (N = 3,013 and N = 3,035 for Job Strain and Emotional demand-control model, resp.) working at public hospitals in Rio de Janeiro, Brazil. Data were collected through a self-report questionnaire. The prevalence of insomnia symptoms was 34.3%. Job strain was associated with increased odds for insomnia symptoms (OR: 2.20); the same result was observed with the combination of emotional demands and low job control (OR: 1.99). In both models, the inclusion of low social support combined with high demands and low job control led to increased odds for insomnia symptoms, compared to groups with high social support from coworkers and supervisors. Besides job strain, the study of emotional demands and social support are promising with regards to insomnia symptoms, particularly among nurses.

  9. Job Strain and Self-Reported Insomnia Symptoms among Nurses: What about the Influence of Emotional Demands and Social Support?

    Directory of Open Access Journals (Sweden)

    Luciana Fernandes Portela

    2015-01-01

    Full Text Available Job strain, derived from high psychological demands and low job control, is associated with insomnia, but information on the role of emotional demands and social support in this relationship is scarce. The aims of this study were (i to test the association between job strain and self-reported insomnia symptoms, (ii to evaluate the combination of emotional demands and job control regarding insomnia symptoms, and (iii to analyze the influence of social support in these relationships. This cross-sectional study refers to a sample of nurses (N = 3,013 and N = 3,035 for Job Strain and Emotional demand-control model, resp. working at public hospitals in Rio de Janeiro, Brazil. Data were collected through a self-report questionnaire. The prevalence of insomnia symptoms was 34.3%. Job strain was associated with increased odds for insomnia symptoms (OR: 2.20; the same result was observed with the combination of emotional demands and low job control (OR: 1.99. In both models, the inclusion of low social support combined with high demands and low job control led to increased odds for insomnia symptoms, compared to groups with high social support from coworkers and supervisors. Besides job strain, the study of emotional demands and social support are promising with regards to insomnia symptoms, particularly among nurses.

  10. 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.

  11. Demand-control-person: integrating the demand-control and conservation of resources models to test an expanded stressor-strain model.

    Science.gov (United States)

    Rubino, Cristina; Perry, Sara Jansen; Milam, Alex C; Spitzmueller, Christiane; Zapf, Dieter

    2012-10-01

    We propose an expanded stressor-strain model that explicitly incorporates person characteristics, the Demand-Control-Person model. This model integrates Karasek's traditional Demand-Control model with Hobfoll's (1989) Conservation of Resources theory. With participants from two organizations, we tested the moderating role of emotional stability in conjunction with two job demands (i.e., uncertainty and time pressure) and control (i.e., decision latitude) in predicting two forms of strain (i.e., job dissatisfaction and disengagement). Our findings support the expanded Demand-Control-Person model, such that a significant three-way interaction emerged for uncertainty and time pressure. As predicted, the traditional Demand-Control model only held among individuals high in emotional stability, such that low-emotional stability individuals did either not benefit as readily from decision latitude or were more susceptible to job demands when they had decision latitude. Thus, the Demand-Control-Person model may provide a more comprehensive model and consistent prediction of the effect of stressors on strain as determined by individual characteristics.

  12. 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 res

  13. 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.

  14. 78 FR 38023 - Demand Response Supporters v. New York Independent System Operator, Inc.; Notice of Complaint

    Science.gov (United States)

    2013-06-25

    ... Energy Regulatory Commission Demand Response Supporters v. New York Independent System Operator, Inc... Commission (Commission), 18 CFR 385.206, Demand Response Supporters (Complainant) filed a formal complaint... NYISO to amend its tariffs to allow demand ] response facilitated by behind-the-meter generation to...

  15. 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.

  16. Demand controlled ventilation in a bathroom

    DEFF Research Database (Denmark)

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

    2008-01-01

    humidity in the bathroom. The two designs differed by the construction of the shower cubicle which in one case was sealed and in the other case unsealed. The construction influenced the relative humidity within the bathroom during a shower, i.e. the pollution source the ventilation rate was controlled by...... of the DCV system was slightly improved in the case with the sealed shower cubicle compared to the unsealed cubicle. The study indicated that indoor climate and energy optimizations of DCV systems should not be limited to considerations of the control system, but should also include considerations......In residential buildings moisture is a dominant pollution source removed by the ventilation system. The Danish building code requires a minimum air change rate of 0.5h-1 in residential buildings to avoid moisture related problems. However a constant ventilation rate results in unnecessary energy...

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

    DEFF Research Database (Denmark)

    Heussen, Kai; You, Shi; Biegel, Benjamin

    2012-01-01

    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......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...

  18. Confiabilidade (teste-reteste da escala sueca do Questionário Demanda-Controle entre Trabalhadores de Restaurantes Industriais do Estado do Rio de Janeiro Test-Retest Reliability of the Swedish Demand-Control-Support Questionnaire among Industrial Restaurant Workers in the State of Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Odaleia Barbosa de Aguiar

    2010-06-01

    Full Text Available OBJETIVO: Este estudo tem o objetivo de verificar a confiabilidade teste-reteste da versão em Português da escala sueca "Demand-Control-Support Questionnaire (DCSQ" em uma população de trabalhadores com baixa escolaridade. MÉTODO: O questionário foi aplicado em dois momentos para 52 trabalhadores de três restaurantes industriais de uma empresa concessionária do Rio de Janeiro, com intervalos de 7 a 15 dias. Como indicadores de estabilidade foram utilizados o Coeficiente de Correlação Intraclasse (CCIC, a estatística Kappa Ponderado e o gráfico de Bland & Altman. Para avaliação da consistência interna utilizou-se o Coeficiente Alpha de Cronbach. RESULTADOS: O CCIC para as dimensões: demanda psicológica, controle do trabalho e apoio social no trabalho foi de 0,70, 0,68 e 0,80, respectivamente. O Alpha de Cronbach apresentou, no reteste, os seguintes resultados: 0,75, 0,50 e 0,82, para as dimensões anteriormente citadas, na mesma sequência. CONCLUSÕES: Ainda que o resultado da escala controle do trabalho tenha sido considerado baixo para o Alpha de Cronbach, os outros indicadores de confiabilidade apontam para uma boa estabilidade do instrumento, possibilitando sua utilização em estudos de associação entre estresse no trabalho e desfechos relacionados à saúde.OBJECTIVE: This study aims to verify the test-retest reliability of the Portuguese version of the Swedish "Demand-Control-Support Questionnaire (DCSQ" scale in a population of workers with low education. METHOD: The questionnaire was administered to 52 employees of three restaurants in industrial companies in Rio de Janeiro twice, with intervals from 7 to 15 days. As indicators of stability, the Intraclass Correlation Coefficient (ICC, weighted Kappa statistics and Bland and Altman's plot were used; for internal consistency evaluation, Cronbach's alpha coefficient was used. RESULTS: The ICCs for the "psychological demand", "decision latitude" and "social support in

  19. 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...... generation. The pollutant generation had two components: a background rate associated with the building materials and furnishings and a second component related to occupants. The demand controlled ventilation system operated at a low airflow rate when the residence was unoccupied and at a high airflow rate...

  20. Demand controlled ventilation for multi-family dwellings

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig

    specify desired levels of indoor air quality through ventilation rate requirements. The Danish Building Code requires a constant air flow rate equivalent to at least 0.5 air changes per hour in residential buildings. A constant air flow requirement is inconsistent with the time varying needs......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...... reduce the electricity consumption by 20% to 30% compared to a system with fixed static pressure control. The results of the project provide more flexible approaches to ventilation design for residences that allow occupancy based DCV approaches to comply with codes and standards that are currently based...

  1. 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.

  2. Development of a demand defrost controller. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Borton, D.N. [Power Kinetics, Troy, NY (United States); Walker, D.H. [Foster-Miller, Inc., Waltham, MA (United States)

    1993-10-01

    The purpose of this project was to develop and commercialize a demand defrost controller that initiates defrosts of refrigeration systems only when required. The standard method of control is a time clock that usually defrosts too often, which wastes energy. The controller developed by this project uses an algorithm based on the temperature difference between the discharge and return of the display case air curtain along with several time settings to defrost only when needed. This controller was field tested in a supermarket where it controlled defrost of the low-temperature display cases. According to test results the controller could reduce annual energy consumption by 20,000 and 62,000 kWh for hot gas and electric defrost, respectively. The controller saves electric demand as well as energy, is adaptable to ambient air conditions, and provides valuable savings throughout the year. The savings are greatest for low-temperature systems that use the most energy. A less tangible benefit of the demand controller is the improvement in food quality that results from fewer defrosts.

  3. 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 quali...

  4. 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.

  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.

  6. Control strategies for demand controlled ventilation in dwellings

    DEFF Research Database (Denmark)

    Nielsen, Toke Rammer; Drivsholm, Christian

    2011-01-01

    . 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...

  7. 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.

  8. 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........ This paper formulates performance measures and an index to evaluate in hind sight the quality of service delivery by an aggregator, both with respect to ancillary service and asset management service. The index is based on requirements formulated in service contracts and provides an overall assessment...

  9. 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.

  10. Job demands × job control interaction effects: do occupation-specific job demands increase their occurrence?

    Science.gov (United States)

    Brough, Paula; Biggs, Amanda

    2015-04-01

    Despite evidence that the accurate assessment of occupational health should include measures of both generic job demands and occupation-specific job demands, most research includes only generic job demands. The inclusion of more focused occupation-specific job demands is suggested to explain a larger proportion of variance for both direct effects and job demands × job control/support interaction effects, as compared with the inclusion of generic job demands. This research tested these two propositions via a self-report survey assessing key psychological job characteristics administered twice to a sample of correctional workers (N = 746). The research clearly identified that the assessment of correctional-specific job demands (CJD) was more strongly associated with job satisfaction, work engagement, turnover intentions and psychological strain, as compared with an assessment of generic job demands. However, the CJD did not produce a greater proportion of significant job demands × job control/support interaction effects, as compared with the generic job demands measure. The results thereby provide further support for the acknowledged 'elusiveness' of these theoretical interactions. Overall, however, the results did support the inclusion of occupation-specific measures of job demands for the accurate assessment of the health and job performance of high-risk workers. The implications for theoretical discussions that describe how high job demands are moderated by job resources are discussed.

  11. 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.

  12. Demand Responsive and Energy Efficient Control Technologies andStrategies in Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Piette, Mary Ann; Kiliccote, Sila

    2006-09-01

    Commercial buildings account for a large portion of summer peak electric demand. Research results show that there is significant potential to reduce peak demand in commercial buildings through advanced control technologies and strategies. However, a better understanding of commercial buildings contribution to peak demand and the use of energy management and control systems is required to develop this demand response resource to its full potential. The main objectives of the study were: (1) To evaluate the size of contributions of peak demand commercial buildings in the U.S.; (2) To understand how commercial building control systems support energy efficiency and DR; and (3) To disseminate the results to the building owners, facility managers and building controls industry. In order to estimate the commercial buildings contribution to peak demand, two sources of data are used: (1) Commercial Building Energy Consumption Survey (CBECS) and (2) National Energy Modeling System (NEMS). These two sources indicate that commercial buildings noncoincidental peak demand is about 330GW. The project then focused on technologies and strategies that deliver energy efficiency and also target 5-10% of this peak. Based on a building operations perspective, a demand-side management framework with three main features: (1) daily energy efficiency, (2) daily peak load management and (3) dynamic, event-driven DR are outlined. A general description of DR, its benefits, and nationwide DR potential in commercial buildings are presented. Case studies involving these technologies and strategies are described. The findings of this project are shared with building owners, building controls industry, researchers and government entities through a webcast and their input is requested. Their input is presented in the appendix section of this report.

  13. Elderly demand for family-based care and support: evidence from a social intervention strategy.

    Science.gov (United States)

    Aboagye, Emmanuel; Agyemang, Otuo Serebour; Tjerbo, Trond

    2013-12-06

    This paper examines the influence of the national health insurance scheme on elderly demand for family-based care and support. It contributes to the growing concern on the rapid increase in the elderly population globally using micro-level social theory to examine the influence the health insurance has on elderly demand for family support. A qualitative case study approach is applied to construct a comprehensive and thick description of how the national health insurance scheme influences the elderly in their demand for family support.Through focused interviews and direct observation of six selected cases, in-depth information on primary carers, living arrangement and the interaction between the health insurance as structure and elders as agents are analyzed. The study highlights that the interaction between the elderly and the national health insurance scheme has produced a new stratum of relationship between the elderly and their primary carers. Consequently, this has created equilibrium between the elderly demand for support and support made available by their primary carers. As the demand of the elderly for support is declining, supply of support by family members for the elderly is also on the decline.

  14. 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.

  15. 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......-concentration is used to ensure adequate ventilation during occupancy and the moisture content is used to ensure adequate removal of moisture produced in the house. The ventilation rate can be switched between two flow rates: a high rate and a low rate. The high flow rate is based on existing requirements...... in the Danish building regulations and the low flow rate is based on minimum requirements in indoor air quality standards. Measurements were performed on an existing single family house where the controls were installed on the existing mechanical ventilation system. The results showed that the ventilation can...

  16. Direct versus Facility Centric Load Control for Automated Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Ed; Piette, Mary Ann

    2009-11-06

    Direct load control (DLC) refers to the scenario where third party entities outside the home or facility are responsible for deciding how and when specific customer loads will be controlled in response to Demand Response (DR) events on the electric grid. Examples of third parties responsible for performing DLC may be Utilities, Independent System Operators (ISO), Aggregators, or third party control companies. DLC can be contrasted with facility centric load control (FCLC) where the decisions for how loads are controlled are made entirely within the facility or enterprise control systems. In FCLC the facility owner has more freedom of choice in how to respond to DR events on the grid. Both approaches are in use today in automation of DR and both will continue to be used in future market segments including industrial, commercial and residential facilities. This paper will present a framework which can be used to differentiate between DLC and FCLC based upon where decisions are made on how specific loads are controlled in response to DR events. This differentiation is then used to compare and contrast the differences between DLC and FCLC to identify the impact each has on:(1)Utility/ISO and third party systems for managing demand response, (2)Facility systems for implementing load control, (3)Communications networks for interacting with the facility and (4)Facility operators and managers. Finally a survey of some of the existing DR related specifications and communications standards is given and their applicability to DLC or FCLC. In general FCLC adds more cost and responsibilities to the facilities whereas DLC represents higher costs and complexity for the Utility/ISO. This difference is primarily due to where the DR Logic is implemented and the consequences that creates. DLC may be more certain than FCLC because it is more predictable - however as more loads have the capability to respond to DR signals, people may prefer to have their own control of end-use loads

  17. Work demands, social support, and job satisfaction in eating disorder inpatient settings: a qualitative study.

    Science.gov (United States)

    Davey, Amanda; Arcelus, Jon; Munir, Fehmidah

    2014-02-01

    In this qualitative study, we aimed to investigate work demands experienced by health-care workers in an adult eating disorder inpatient service. We also aimed to investigate the use of social support and job satisfaction in this setting. Twelve health-care workers from an eating disorder inpatient ward, including nurses, health-care support workers, and occupational therapists, participated in semistructured interviews. Interviews were transcribed verbatim and analysed using thematic analysis. A number of work demands were discussed relating to therapeutic care, physical care, and organizational demands. Most participants discussed social support at work as being highly valuable, formally and informally, whereas external support was viewed as less important. Despite the challenges of caring for patients with eating disorders, the majority of participants reported good patient-related job satisfaction, but poor job satisfaction in relation to organizational factors. Eating disorder inpatient care is complex and demanding, necessitating effective teamwork, communication, and support systems among health-care workers. Interventions should be developed to target barriers to care, including time constraints, administrative workload, and insufficient allocation of staff.

  18. 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.

  19. 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.

  20. 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

  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. 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 dema

  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. Control, Operator Support and Safety System of PVC-reactors

    Directory of Open Access Journals (Sweden)

    Jens I. Ytreeide

    1997-01-01

    Full Text Available In modern petrochemical plants the corporate and societal demands to plant safety and minimum environmental effects are high. These demands rise high performance requirements to the technical systems, specially the process control and safety systems including an effective operator support system with fault detection capability. The systems must have high reliability also against erroneous operations which may cause shutdown situations or quality deviations.

  5. 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

  6. Industrial power monitoring and control : Power management system helps plant reduce energy demand

    Energy Technology Data Exchange (ETDEWEB)

    Crossley, L.E. [E2MS Inc., Whitby, ON (Canada); Demysh, M. [Diversa Cast Technologies, Guelph, ON (Canada)

    2001-05-01

    A power management system, consisting of a real time demand management system designed to allow managers to reduce operating costs via the automatic control of plant furnace loads with interference to production kept to a minimum, was installed at Diversa Cast Technologies in Guelph, Ontario. Diversa Cast Technologies manufactures aluminium, gray and ductile iron automotive lost foam castings. The potential load at the plant is approximately 5000 kW, and comprises two coreless induction melters and supporting equipment. Used for iron batch melting in the off peak hours between 2300 hours and 0700 hours, the first melter is rated at 2750 kW with 8000 lbs capacity. The aluminium heal melting during the on peak hours is handled by the second melter rated at 1250 kW with a 2700 lbs capacity. The electric utility operates on a time-of-use basis which includes penalties for on-peak demand. The installation of the system is described, along with its operation. The software comprises a number of modules to control all the necessary functions associated with data acquisition and analysis. The modules include: communications module, display module, analysis module, report module, database filer, and a system and cost configuration module. Commissioned in February 2000, the system has operated for approximately two months. After the initial period of two weeks where the system was in a monitoring mode to determine the baseline of energy demand and consumption, the demand control was activated. The numerous advantages of the system include better efficiency in the way energy is used, a reduction in the power factor penalties, power factor savings. The payback for this system is less than 8 months. The overall demand was lowered, the productivity improved along with the energy consumption efficiency. 4 figs.

  7. Supporting Urban Planning of Low-Carbon Precincts: Integrated Demand Forecasting

    Directory of Open Access Journals (Sweden)

    Steffen Lehmann

    2013-12-01

    Full Text Available Waste is a symbol of inefficiency in modern society and represents misallocated resources. This paper outlines an on-going interdisciplinary research project entitled “Integrated ETWW demand forecasting and scenario planning for low-carbon precincts” and reports on first findings and a literature review. This large multi-stakeholder research project develops a shared platform for integrated ETWW (energy, transport, waste and water planning in a low-carbon urban future, focusing on synergies and alternative approaches to urban planning. The aim of the project is to develop a holistic integrated software tool for demand forecasting and scenario evaluation for residential precincts, covering the four domains, ETWW, using identified commonalities in data requirements and model formulation. The authors of this paper are overseeing the waste domain. A major component of the project will be developing a method for including the impacts of household behavior change in demand forecasting, as well as assessing the overall carbon impacts of urban developments or redevelopments of existing precincts. The resulting tool will allow urban planners, municipalities and developers to assess the future total demands for energy, transport, waste and water whilst in the planning phase. The tool will also help to assess waste management performance and materials flow in relation to energy and water consumption and travel behavior, supporting the design and management of urban systems in different city contexts.

  8. Seismic Demands for Pile-Supported Wharf Structures with Batter Piles

    Directory of Open Access Journals (Sweden)

    Rouhollah Amirabadi

    2012-09-01

    Full Text Available This study develops an optimal Probabilistic Seismic Demand Model (PSDM for pile-supported wharves whit batter plies. Four bins with twenty non-near-field ground motions and three typical pile-supported wharf structures from western United States ports are used to determine an optimal PSDM by using Probabilistic Seismic Demand Analysis (PSDA. PSDA is used to compute the relationship between Engineering Demand Parameters (EDPs and earthquake Intensity Measures (IMs. An optimal PSDM should be practical, sufficient, effective and efficient-all tested through several IM-EDP pairs. It has been found that for these types of structures, the optimal model comprises a spectral IM, such as spectral acceleration and one of several EDPs. These EDPs are considered for local (moment curvature ductility factor, intermediate (displacement ductility factor and horizontal displacement of embankment and global (differential settlement between deck and behind land response quantities. The considered PSDMs are a critical component in performance-based seismic design and seismic risk assessment. Results can be used in probabilistic framework for performance-based design developed by Pacific Earthquake Engineering Research (PEER center.

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

    Science.gov (United States)

    Höing, Mechtild; Bogaerts, Stefan; Vogelvang, Bas

    2015-10-21

    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.

  10. 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.

  11. Artificial Neural Networks and Support Vector Machines for Water Demand Time Series Forecasting

    CERN Document Server

    Msiza, Ishmael S; Nelwamondo, Fulufhelo Vincent

    2007-01-01

    Water plays a pivotal role in many physical processes, and most importantly in sustaining human life, animal life and plant life. Water supply entities therefore have the responsibility to supply clean and safe water at the rate required by the consumer. It is therefore necessary to implement mechanisms and systems that can be employed to predict both short-term and long-term water demands. The increasingly growing field of computational intelligence techniques has been proposed as an efficient tool in the modelling of dynamic phenomena. The primary objective of this paper is to compare the efficiency of two computational intelligence techniques in water demand forecasting. The techniques under comparison are the Artificial Neural Networks (ANNs) and the Support Vector Machines (SVMs). In this study it was observed that the ANNs perform better than the SVMs. This performance is measured against the generalisation ability of the two.

  12. Control for large scale demand response of thermostatic loads

    DEFF Research Database (Denmark)

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

    2013-01-01

    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...... 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...

  13. The demand control model and circadian saliva cortisol variations in a Swedish population based sample (The PART study

    Directory of Open Access Journals (Sweden)

    de la Torre Bartolomé

    2006-11-01

    Full Text Available Abstract Background Previous studies of the relationship between job strain and blood or saliva cortisol levels have been small and based on selected occupational groups. Our aim was to examine the association between job strain and saliva cortisol levels in a population-based study in which a number of potential confounders could be adjusted for. Methods The material derives from a population-based study in Stockholm on mental health and its potential determinants. Two data collections were performed three years apart with more than 8500 subjects responding to a questionnaire in both waves. In this paper our analyses are based on 529 individuals who held a job, participated in both waves as well as in an interview linked to the second wave. They gave saliva samples at awakening, half an hour later, at lunchtime and before going to bed on a weekday in close connection with the interview. Job control and job demands were assessed from the questionnaire in the second wave. Mixed models were used to analyse the association between the demand control model and saliva cortisol. Results Women in low strain jobs (high control and low demands had significantly lower cortisol levels half an hour after awakening than women in high strain (low control and high demands, active (high control and high demands or passive jobs (low control and low demands. There were no significant differences between the groups during other parts of the day and furthermore there was no difference between the job strain, active and passive groups. For men, no differences were found between demand control groups. Conclusion This population-based study, on a relatively large sample, weakly support the hypothesis that the demand control model is associated with saliva cortisol concentrations.

  14. 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).

  15. The Library Space Problem, Future Demand, and Collection Control.

    Science.gov (United States)

    Lee, Hur-Li

    1993-01-01

    Outlines a model for determining library collection use, incorporating prediction of future demand and cost analysis to assist collection development librarians determine whether weeding or remote storage is the most economically feasible way to address the space problem in libraries. (13 references) (EA)

  16. 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 powe

  17. 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

    , particularly in regions that are weakly interconnected with their surrounding areas, such as small islands. This paper addresses the problem of frequency control in isolated power systems with relevant inclusion of wind power generation. With this aim, we have analyzed the contribution of the demand side......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...

  18. 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

  19. Supported employment: randomised controlled trial*

    Science.gov (United States)

    Howard, Louise M.; Heslin, Margaret; Leese, Morven; McCrone, Paul; Rice, Christopher; Jarrett, Manuela; Spokes, Terry; Huxley, Peter; Thornicroft, Graham

    2010-01-01

    Background There is evidence from North American trials that supported employment using the individual placement and support (IPS) model is effective in helping individuals with severe mental illness gain competitive employment. There have been few trials in other parts of the world. Aims To investigate the effectiveness and cost-effectiveness of IPS in the UK. Method Individuals with severe mental illness in South London were randomised to IPS or local traditional vocational services (treatment as usual) (ISRCTN96677673). Results Two hundred and nineteen participants were randomised, and 90% assessed 1 year later. There were no significant differences between the treatment as usual and intervention groups in obtaining competitive employment (13% in the intervention group and 7% in controls; risk ratio 1.35, 95% CI 0.95–1.93, P = 0.15), nor in secondary outcomes. Conclusions There was no evidence that IPS was of significant benefit in achieving competitive employment for individuals in South London at 1-year follow-up, which may reflect suboptimal implementation. Implementation of IPS can be challenging in the UK context where IPS is not structurally integrated with mental health services, and economic disincentives may lead to lower levels of motivation in individuals with severe mental illness and psychiatric professionals. PMID:20435968

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    manage the portfolio of devices to collectively provide a primary reserve delivery in an unbundled liberalized electricity market setting under current regulations. Furthermore, we formulate a binary linear optimization problem that minimizes the aggregator’s cost of providing a primary reserve delivery......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...

  1. 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...

  2. Social support moderates the impact of demands on burnout and organizational connectedness: a two-wave study of volunteer firefighters.

    Science.gov (United States)

    Huynh, Jasmine Y; Xanthopoulou, Despoina; Winefield, Anthony H

    2013-01-01

    This two-wave study of volunteers examined the effect of family and friend support on the relationship between volunteer demands (emotional demands and work-home conflict) on the one hand, and burnout (exhaustion and cynicism) and organizational connectedness on the other hand. It was hypothesized that family and friend support would moderate the relationship between (a) demands at Time 1 (T1) and burnout at Time 2 (T2); and (b) demands at T1 and organizational connectedness at T2. Hypotheses were tested among 126 Australian volunteer firefighters, who were followed up over 1 year. Results showed that support moderated the relationship between work-home conflict and exhaustion, but not between emotional demands and exhaustion. In addition, family and friend support moderated the relationship between both volunteer demands at T1 and cynicism and organizational connectedness at T2. These results suggest that support from family and friends is a critical resource in coping with the demands related to volunteer work and may protect volunteers from burnout, while helping them to stay connected to volunteering. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  3. Control and Optimization Meet the Smart Power Grid - Scheduling of Power Demands for Optimal Energy Management

    CERN Document Server

    Koutsopoulos, Iordanis

    2010-01-01

    The smart power grid aims at harnessing information and communication technologies to enhance reliability and enforce sensible use of energy. Its realization is geared by the fundamental goal of effective management of demand load. In this work, we envision a scenario with real-time communication between the operator and consumers. The grid operator controller receives requests for power demands from consumers, with different power requirement, duration, and a deadline by which it is to be completed. The objective is to devise a power demand task scheduling policy that minimizes the grid operational cost over a time horizon. The operational cost is a convex function of instantaneous power consumption and reflects the fact that each additional unit of power needed to serve demands is more expensive as demand load increases.First, we study the off-line demand scheduling problem, where parameters are fixed and known. Next, we devise a stochastic model for the case when demands are generated continually and sched...

  4. Demand as Frequency Controlled Reserve: Implementation and practical demonstration

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Nyeng, Preben

    2011-01-01

    One of the challenges in electric power systems with a high penetration of renewable generation is the provision of ancillary services. Traditionally these services have been provided by conventional generation, but as power from renewable sources (wind and PV) displaces conventional generation......, new providers of ancillary services are needed. Frequency regulation is critical because fluctuating energy sources increase the need for this service. At very high levels of renewable penetration, all available frequency regulation services will be called on, including demand-side resources. Electric...... loads that provide thermal energy services are attractive because their heat capacity allows electric power consumption to be moved in time without degrading the quality of service. This concept is being demonstrated in field tests on the island of Bornholm, Denmark....

  5. Demand as Frequency Controlled Reserve: Implementation and practical demonstration

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Nyeng, Preben;

    2011-01-01

    , new providers of ancillary services are needed. Frequency regulation is critical because fluctuating energy sources increase the need for this service. At very high levels of renewable penetration, all available frequency regulation services will be called on, including demand-side resources. Electric......One of the challenges in electric power systems with a high penetration of renewable generation is the provision of ancillary services. Traditionally these services have been provided by conventional generation, but as power from renewable sources (wind and PV) displaces conventional generation...... loads that provide thermal energy services are attractive because their heat capacity allows electric power consumption to be moved in time without degrading the quality of service. This concept is being demonstrated in field tests on the island of Bornholm, Denmark....

  6. Combined Sales Effort and Inventory Control under Demand Uncertainty

    Directory of Open Access Journals (Sweden)

    Weili Xue

    2013-01-01

    Full Text Available We study the joint inventory and sales effort management problems of a retailer in a broad context and investigate the optimal policies for a single item, periodic-review system. In each period, the demand is uncertain depending on the sales effort level exerted by the retailer, which incurs an associated cost. The retailer’s objective is to find a joint optimal inventory replenishment and sales effort policy to maximize the discounted profit over a finite horizon. We first consider a basic setting with zero setup cost and no batch ordering, under which the base stock list sales effort policy is optimal. Two extensions are then investigated: (1 the case with nonzero setup cost, under which we show that (s,S,e policy is optimal; and (2 the case with batch ordering, under which we prove the optimality of the (r,Nq,e policy. Finally, we conduct numerical studies to provide additional managerial insights.

  7. Application of demand-control theory to sign language interpreting: implications for stress and interpreter training.

    Science.gov (United States)

    Dean, R K; Pollard, R Q

    2001-01-01

    The translation work of sign language interpreters involves much more than language. The characteristics and goings-on in the physical environment, the dynamics and interactions between the people who are present, and even the "inner noise" of the interpreter contribute to the accuracy, or lack thereof, of the resulting translation. The competent interpreter must understand and respond appropriately to the language and nonlanguage aspects of each interpreting assignment. We use the framework of demand-control theory (Karasek, 1979) to examine the complex occupation of sign language interpreting. Demand-control theory is a job analysis method useful in studies of occupational stress and reduction of stress-related illness, injury, and burnout. We describe sources of demand in the interpreting profession, including demands that arise from factors other than those associated with languages (linguistic demands). These include environmental, interpersonal, and intrapersonal demands. Karasek's concept of control, or decision latitude, is also explored in relation to the interpreting profession. We discuss the prevalence of cumulative trauma disorders (CTD), turnover, and burnout in the interpreting profession in light of demand-control theory and data from interpreter surveys, including a new survey study described herein. We conclude that nonlinguistic demand factors in particular and perceived restrictions in decision latitude likely contribute to stress, CTD, burnout, and the resulting shortage of sign language interpreters. We make suggestions for improvements in interpreter education and professional development, including the institution of an advanced, supervised professional training period, modeled after internships common in other high demand professional occupations.

  8. 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.

  9. 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.

  10. Control, operator support and safety system of PVC reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ytreeide, J.I.; Aaker, O.; Kristoffersen, V.; Moe, G.; Naustdal, C.

    1997-06-01

    In modern petrochemical plants the corporate and societal demands to plant safety and minimum environmental effects are high. These demands rise high performance requirements to the technical systems, specially the process control and safety systems including an effective operator support system with fault detection capability. PVC producing plants have high inherent hazard potentials, and the studied reaction in this publication is exothermic and non-linear and open-loop unstable, and the plant is equipped with two independent cooling systems to keep the reaction under control. A system to solve the stability problem of parallel control is suggested, showing the simulation of real process data. The publication describes an operator support system for monitoring the heat of reaction in the autoclave consisting of a model based estimator. The system is tested on-line, and the results of simulations and on-line estimates are presented. 6 refs., 13 figs.

  11. 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

    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...

  12. Helicopter Flight Control Research - A Demanding Application of Piloted Simulation.

    Science.gov (United States)

    1986-01-01

    Sigma-8 digital computer (used to run the aircraft mathematical model) and an Applied Dynamics AD-4 analogue computer (used principally as a flexible...interface to cockpit instruments, and for motion and visual systems operation) (Fig 4). The first helicopter simulation to use a digital aircraft...34 Control Technology for helicopters. For fixed-wing aircraft, impresive claims were being made for electrically (and later optically) signalled control

  13. [Demand-Control model and occupational stress among nursing professionals: integrative review].

    Science.gov (United States)

    Schmidt, Denise Rodrigues Costa

    2013-01-01

    The Demand Control model aims to evaluate the occupational stress. This study aimed to know, through an integrative review of the literature, the scientific production about the Demand Control Model to investigation occupational stress among nursing professionals from 2000 to 2011.Of the 16 selected studies, five were published in 2009. Of these studies, 56.25% assessed the Demand and Control dimensions and their correlations with workers' health problems; 37.5% of these studies were related with mental health. The results showed a lack of national publications. We recommend that authors conduct experimental studies to reduce the occupational stress for better conditions of workers' mental health.

  14. 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.

  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. 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…

  17. Energy efficient demand controlled ventilation in single family houses

    DEFF Research Database (Denmark)

    Nielsen, Toke Rammer; Drivsholm, Christian

    2010-01-01

    in the Danish building regulations and the low flow rate is based on minimum requirements in indoor air quality standards. Measurements were performed on an existing single family house where the controls were installed on the existing mechanical ventilation system. The results showed that the ventilation can...

  18. Aging and Concurrent Task Performance: Cognitive Demand and Motor Control

    Science.gov (United States)

    Albinet, Cedric; Tomporowski, Phillip D.; Beasman, Kathryn

    2006-01-01

    A motor task that requires fine control of upper limb movements and a cognitive task that requires executive processing--first performing them separately and then concurrently--was performed by 18 young and 18 older adults. The motor task required participants to tap alternatively on two targets, the sizes of which varied systematically. The…

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

    OpenAIRE

    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.

  20. Advanced Controls and Communications for Demand Response andEnergy Efficiency in Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Kiliccote, Sila; Piette, Mary Ann; Hansen, David

    2006-01-17

    Commercial buildings account for a large portion of summer peak demand. Research results show that there is significant potential to reduce peak demand in commercial buildings through advanced control technologies and strategies. However, a better understanding of commercial building's contribution to peak demand and the use of energy management and control systems is required to develop this demand response resource to its full potential. This paper discusses recent research results and new opportunities for advanced building control systems to provide demand response (DR) to improve electricity markets and reduce electric grid problems. The main focus of this paper is the role of new and existing control systems for HVAC and lighting in commercial buildings. A demand-side management framework from building operations perspective with three main features: daily energy efficiency, daily peak load management and event driven, dynamic demand response is presented. A general description of DR, its benefits, and nationwide potential in commercial buildings is outlined. Case studies involving energy management and control systems and DR savings opportunities are presented. The paper also describes results from three years of research in California to automate DR in buildings. Case study results and research on advanced buildings systems in New York are also presented.

  1. 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...

  2. 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

    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...

  3. 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

  4. 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

  5. Computer support for mechatronic control system design

    NARCIS (Netherlands)

    van Amerongen, J.; Coelingh, H.J.; de Vries, Theodorus J.A.

    2000-01-01

    This paper discusses the demands for proper tools for computer aided control system design of mechatronic systems and identifies a number of tasks in this design process. Real mechatronic design, involving input from specialists from varying disciplines, requires that the system can be represented

  6. Air conditioning versus heating: climate control is more energy demanding in Minneapolis than in Miami

    Science.gov (United States)

    Sivak, Michael

    2013-03-01

    Energy demand for climate control was analyzed for Miami (the warmest large metropolitan area in the US) and Minneapolis (the coldest large metropolitan area). The following relevant parameters were included in the analysis: (1) climatological deviations from the desired indoor temperature as expressed in heating and cooling degree days, (2) efficiencies of heating and cooling appliances, and (3) efficiencies of power-generating plants. The results indicate that climate control in Minneapolis is about 3.5 times as energy demanding as in Miami. This finding suggests that, in the US, living in cold climates is more energy demanding than living in hot climates.

  7. 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

    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...... distributed energy resources and flexible demand as a regulating resource. Furthermore, the results illustrate and verify the applicability of the concept and the proposed infrastructure for controlling distributed energy resources and flexible demand....... 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...

  8. 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…

  9. 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.

  10. Metabolic Demand and Muscle Activation during Different Forms of Bodyweight Supported Locomotion in Men with Incomplete SCI

    Directory of Open Access Journals (Sweden)

    Alyssa M. Fenuta

    2014-01-01

    Full Text Available Body weight supported locomotor training uses neuroplasticity principles to improve recovery following a spinal cord injury (SCI. Steady state locomotion using the same body weight support (BWS percent was compared in 7 males (42.6 ± 4.29 years with incomplete SCI and matched (gender, age noninjured controls (42.7 ± 5.4 years using the Lokomat, Manual Treadmill, and ZeroG. The VO2000, Polar Heart Rate (HR Monitor, and lower limb electromyography (EMG electrodes were worn during the 2-minute sessions. Oxygen uptake (VO2 and HR were expressed as percentage of peak values obtained using progressive arm ergometry; VO2 was also expressed relative to resting metabolic equivalents (METS. Filtered EMG signals from tibialis anterior (TA, rectus femoris (RF, biceps femoris (BF, and medial gastrocnemius (MG were normalized to ZeroG stepping. The Lokomat required 30% of VO2 peak (2METS compared to ~54% (3METS for Manual Treadmill and ZeroG sessions. HR was 67% of peak during Lokomat sessions compared to ~83% for Manual Treadmill and ZeroG. Muscle activation was higher in treadmill conditions compared to the ZeroG primarily due to increased BF activity. At the same level of BWS, locomotion using the Manual Treadmill or the ZeroG is more aerobically demanding than the Lokomat. Treadmill modalities encourage greater hip extensor activation compared to overground locomotion.

  11. 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.

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

    OpenAIRE

    Zong, Yi; You, Shi; Hu, Junjie; Han, Xue; Jiang, Chongxi; Zhang, Yi; Böning, Georg Martin

    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 architecture design for Model Predictive Controller (MPC), and discusses the challenges encountered during the implementation of MPC for active demand side management. The two different pilot case studies ...

  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 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.

  15. Scheduling and control of failure prone systems with demand uncertainty and job overlaps

    Institute of Scientific and Technical Information of China (English)

    Jun LIU; Ping LI; Zhihuan SONG

    2004-01-01

    Given that the overlapping of jobs is permitted,the paper studies the scheduling and control of failure prone production systems,i.e.so-called settings with demand uncertainty and job overlaps.Because a variable demand resource is involved in the production and corrective maintenance control problems of the system,which switched randomly between zero and a maximum level,it is difficult to obtain the analytical solutions of the optimal single hedging point policy.An asymptotic optimal scheduling policy is presented and a double hedging point policy is offered to control simultaneously the production rate and the corrective maintenance rate of the system.The corresponding analytical solutions and approximate solutions are obtained.Considering the relationship of production,corrective maintenance and demand variable,an approximate optimal single hedging point control policy is proposed.Numerical results are presented.

  16. 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.

  17. 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...

  18. 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.

  19. A comparison between the effort-reward imbalance and demand control models.

    Science.gov (United States)

    Ostry, Aleck S; Kelly, Shona; Demers, Paul A; Mustard, Cameron; Hertzman, Clyde

    2003-02-27

    To compare the predictive validity of the demand/control and reward/imbalance models, alone and in combination with each other, for self-reported health status and the self-reported presence of any chronic disease condition. Self-reports for psychosocial work conditions were obtained in a sample of sawmill workers using the demand/control and effort/reward imbalance models. The relative predictive validity of task-level control was compared with effort/reward imbalance. As well, the predictive validity of a model developed by combining task-level control with effort/reward imbalance was determined. Logistic regression was utilized for all models. The demand/control and effort/reward imbalance models independently predicted poor self-reported health status. The effort-reward imbalance model predicted the presence of a chronic disease while the demand/control model did not. A model combining effort-reward imbalance and task-level control was a better predictor of self-reported health status and any chronic condition than either model alone. Effort reward imbalance modeled with intrinsic effort had marginally better predictive validity than when modeled with extrinsic effort only. Future work should explore the combined effects of these two models of psychosocial stress at work on health more thoroughly.

  20. Does psychological distress influence reporting of demands and control at work?

    Science.gov (United States)

    Waldenstrom, K; Lundberg, I; Waldenstrom, M; Harenstam, A; MOA, R

    2003-01-01

    Aims: To investigate whether self reporting of psychological demands and control at work is as valid for psychologically distressed subjects as for subjects with psychological wellbeing. Method: Self reported demands and control (according to the model of Karasek) were compared to expert assessments through direct observations of each subject's work conditions concerning time pressure, hindrances, qualification for work tasks, and possibility of having influence. The comparison was made between respondents reporting and not reporting psychological distress as measured by the general health questionnaire with 12 questions (GHQ-12). The sample consisted of 203 men and women in 85 occupations. Result: No systematic differences between self reported and externally assessed working conditions for respondents reporting different levels of psychological distress were found. Conclusion: Over-reporting of work demands or under-reporting of work control is unlikely at the levels of psychological distress studied. PMID:14573721

  1. 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.

  2. 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...... 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 that the new procedures were considerably...

  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

    -conditioning systems. The warehouse logistics 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...... 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. Linking meters and markets: Roles and incentives to support a flexible demand side

    DEFF Research Database (Denmark)

    Katz, Jonas

    2014-01-01

    participants. The roll-out of smart metering to electricity consumers is an important precondition to establishing a flexible demand side and will provide essential information flows. On the basis of current incentive structures and related risks, however, the pass-through of information and value from...... 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...... 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...

  5. 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…

  6. 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…

  7. Effects of working memory demand on neural mechanisms of motor response selection and control.

    Science.gov (United States)

    Barber, Anita D; Caffo, Brian S; Pekar, James J; Mostofsky, Stewart H

    2013-08-01

    Inhibitory control commonly recruits a number of frontal regions: pre-supplementary motor area (pre-SMA), frontal eye fields (FEFs), and right-lateralized posterior inferior frontal gyrus (IFG), dorsal anterior insula (DAI), dorsolateral prefrontal cortex (DLPFC), and inferior frontal junction (IFJ). These regions may directly implement inhibitory motor control or may be more generally involved in executive control functions. Two go/no-go tasks were used to distinguish regions specifically recruited for inhibition from those that additionally show increased activity with working memory demand. The pre-SMA and IFG were recruited for inhibition in both tasks and did not have greater activation for working memory demand on no-go trials, consistent with a role in inhibitory control. Activation in pre-SMA also responded to response selection demand and was increased with working memory on go trials specifically. The bilateral FEF and right DAI were commonly active for no-go trials. The FEF was also recruited to a greater degree with working memory demand on go trials and may bias top-down information when stimulus-response mappings change. The DAI, additionally responded to increased working memory demand on both go and no-go trials and may be involved in accessing sustained task information, alerting, or autonomic changes when cognitive demands increase. DLPFC activation was consistent with a role in working memory retrieval on both go and no-go trials. The inferior frontal junction, on the other hand, had greater activation with working memory specifically for no-go trials and may detect salient stimuli when the task requires frequent updating of working memory representations.

  8. 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....

  9. High Job Demands and Low Job Control Increase Nurses' Professional Leaving Intentions: The Role of Care Setting and Profit Orientation.

    Science.gov (United States)

    Wendsche, Johannes; Hacker, Winfried; Wegge, Jürgen; Rudolf, Matthias

    2016-10-01

    We investigated how two types of care setting (home care and nursing home) and type of ownership (for-profit vs. public/non-profit) of geriatric care services interacted in influencing registered nurses' intention to give up their profession. In prior research, employment in for-profit-organizations, high job demands, and low job control were important antecedents of nurses' intent to leave. However, the impact of care setting on these associations was inconclusive. Therefore, we tested a mediated moderation model predicting that adverse work characteristics would drive professional leaving intentions, particularly in for-profit services and in nursing homes. A representative German sample of 304 registered nurses working in 78 different teams participated in our cross-sectional study. As predicted, lower job control and higher job demands were associated with higher professional leaving intentions, and nurses reported higher job demands in public/non-profit care than in for-profit care, and in nursing homes compared to home care. Overall, RNs in nursing homes and home care reported similar intent to leave, but in for-profit settings only, nurses working in nursing homes reported higher professional leaving intentions than did nurses in home care, which was linked to lower job control in the for-profit nursing home setting, supporting mediated moderation. Taken together, our results indicate that the interplay of care setting and type of ownership is important when explaining nurses' intentions to give up their profession. © 2016 Wiley Periodicals, Inc.

  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. 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…

  12. 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

    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...

  13. 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…

  14. 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

  15. 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 par

  16. 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

    networks must be matched to small dynamic loads, while spinning reserves of conventional generation that are required to maintain security of supply, must be reduced to more efficient margins. Domestic loads, likely to form significant proportions of the loads on islanded power systems such as those......With conventional generation capacity being constrained on environmental grounds and renewable alternatives carrying capacity uncertainties, increasingly accurate forecasts of demand are likely to be required in future power systems: highly distributed renewable generation penetrating low voltage...... 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...

  17. 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

    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......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......, 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...

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

    DEFF Research Database (Denmark)

    Zong, Yi; You, Shi; Hu, Junjie

    2015-01-01

    architecture design for Model Predictive Controller (MPC), and discusses the challenges encountered during the implementation of MPC for active demand side management. The two different pilot case studies show that energy savings and load shifting can be achieved by applying MPC with weather forecast......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...

  19. 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

    -conditioning systems. The warehouse logistics 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...... that the new procedures provided a better fit with the actual demand processes and were more consistent with the stated objectives for the distribution centre. We also initiated the implementation and integration of the new procedures into the company's inventory management system....

  20. Distributed Power Control Network and Green Building Test-Bed for Demand Response in Smart Grid

    Science.gov (United States)

    Sakaguchi, Kei; Nguyen, Van Ky; Tao, Yu; Tran, Gia Khanh; Araki, Kiyomichi

    It is known that demand and supply power balancing is an essential method to operate power delivery system and prevent blackouts caused by power shortage. In this paper, we focus on the implementation of demand response strategy to save power during peak hours by using Smart Grid. It is obviously impractical with centralized power control network to realize the real-time control performance, where a single central controller measures the huge metering data and sends control command back to all customers. For that purpose, we propose a new architecture of hierarchical distributed power control network which is scalable regardless of the network size. The sub-controllers are introduced to partition the large system into smaller distributed clusters where low-latency local feedback power control loops are conducted to guarantee control stability. Furthermore, sub-controllers are stacked up in an hierarchical manner such that data are fed back layer-by-layer in the inbound while in the outbound control responses are decentralized in each local sub-controller for realizing the global objectives. Numerical simulations in a realistic scenario of up to 5000 consumers show the effectiveness of the proposed scheme to achieve a desired 10% peak power saving by using off-the-shelf wireless devices with IEEE802.15.4g standard. In addition, a small scale power control system for green building test-bed is implemented to demonstrate the potential use of the proposed scheme for power saving in real life.

  1. ENGINEERING SUPPORT PARADIGM OF SUBJECT-ORIENTED CONTROL TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    Kharitonov V. A.

    2015-10-01

    Full Text Available The article presents the basic antilogy, which is attributed to forming an engineering support paradigm of new technologies related to the subject-oriented control in the noosphere, between the demand for an automatical creative thinking of a control subject and the vigilance of society to possible adverse effects of its subjective activities. It is stated that the noosphere, which showed miracles of automation and cybernation, covers all types of human activities, excluding above original positions, which they barely touched. Uppermost it is related to the central economics problem (economy management – the choice. The problem how to build an engineering support paradigm of subject-oriented control technologies is analyzed; it is based on the known subject-oriented control concept supplemented by concept-based models of the intuition mechanism, which assume its modeling based on formal systems with the purpose to automate control subjects mental activity. From the standpoint of Schopenhauer’s cognitive theory, a research method is developed to investigate evolution and becoming of a particular human category – engineers, which are responsible for the steady development of noosphere of Vernadsky. As a basis, a dynamic phylogenesis model of engineer’s figure was taken, including ready and effective vectors with parameters (education, intellect, skills and (prevision, choice, emergence, respectively. The results of ontogenesis modeling are given – regularities in future engineers’ preparation as a platform for quantization and convolution of its levels based on modern mathematical methods, including those for support engineers of subjectoriented control technologies

  2. 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.

  3. 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.

  4. Hierarchical control framework for integrated coordination between distributed energy resources and demand response

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Di; Lian, Jianming; Sun, Yannan; Yang, Tao; Hansen, Jacob

    2017-09-01

    Demand response is representing a significant but largely untapped resource that can greatly enhance the flexibility and reliability of power systems. In this paper, a hierarchical control framework is proposed to facilitate the integrated coordination between distributed energy resources and demand response. The proposed framework consists of coordination and device layers. In the coordination layer, various resource aggregations are optimally coordinated in a distributed manner to achieve the system-level objectives. In the device layer, individual resources are controlled in real time to follow the optimal power generation or consumption dispatched from the coordination layer. For the purpose of practical applications, a method is presented to determine the utility functions of controllable loads by taking into account the real-time load dynamics and the preferences of individual customers. The effectiveness of the proposed framework is validated by detailed simulation studies.

  5. Decision Support for effective production control

    DEFF Research Database (Denmark)

    Africa, E.; Nehzati, T.; Strandhagen, J.O.

    2012-01-01

    This study aims to identify the actual needs of decision makers for decision support in the production control activity, considering the role and cognitive skills of human decision-makers in the decision-making process. Multiple case studies have been conducted in order to gain practical insights...... from the manufacturing industry. This paper contributes to raise the issues that should be considered for successful implementation of the decision support systems in practice....

  6. Volunteers in Circles of Support and Accountability : Job demands, job resources, and outcome

    NARCIS (Netherlands)

    Höing, M.A.; Vogelvang, B.; Bogaerts, Stefan

    2016-01-01

    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 volu

  7. Volunteers in circles of support and accountability : Job demands, job resources, and outcome

    NARCIS (Netherlands)

    Höing, M.A.; Vogelvang, B.; Bogaerts, Stefan

    2017-01-01

    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 volu

  8. Blockbusters and controlled substances: Miltown, Quaalude, and consumer demand for drugs in postwar America.

    Science.gov (United States)

    Herzberg, David

    2011-12-01

    In 1955 Carter Products launched its new tranquilizer Miltown with a huge marketing blitz; Miltown soon became one of America's earliest "blockbuster" celebrity drugs. In 1981, federal agents shut down a network of "stress clinics" and arrested the owners, medical staff, and other personnel for illegally trafficking in the sedative Quaalude; Quaalude soon became a "Schedule I Controlled Substance." Both of these stories are familiar, indeed archetypal, moments from America's postwar medical system. As the Miltown example reminds us, this fundamentally commercial system was built on the creation and courting of consumer demand for medical products and services, particularly drugs. As the Quaalude example shows, however, this system also incorporated tools for reining in excessive consumer demand. Together the two episodes affirm an enduring irony of the American medical system: the need for regulatory campaigns to tame lively markets for drugs that had become popular, in part, because of advertising campaigns. This article uses the Miltown and Quaalude sagas to explore the issue of consumer demand for prescription medicines, arguing that efforts to stoke or quash that demand have shaped (and linked) America's medical system and its drug control regimes.

  9. Aggregated Modeling and Control of Air Conditioning Loads for Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei; Lian, Jianming; Chang, Chin-Yao; Kalsi, Karanjit

    2013-06-21

    Demand response is playing an increasingly important role in the efficient and reliable operation of the electric grid. Modeling the dynamic behavior of a large population of responsive loads is especially important to evaluate the effectiveness of various demand response strategies. In this paper, a highly-accurate aggregated model is developed for a population of air conditioning loads. The model effectively includes statistical information of the population, systematically deals with load heterogeneity, and accounts for second-order dynamics necessary to accurately capture the transient dynamics in the collective response. Based on the model, a novel aggregated control strategy is designed for the load population under realistic conditions. The proposed controller is fully responsive and achieves the control objective without sacrificing end-use performance. The proposed aggregated modeling and control strategies are validated through realistic simulations using GridLAB-D. Extensive simulation results indicate that the proposed approach can effectively manage a large number of air conditioning systems to provide various demand response services, such as frequency regulation and peak load reduction.

  10. 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.

  11. A multilevel analysis of the demands--control model: is stress at work determined by factors at the group level or the individual level?

    Science.gov (United States)

    Van Yperen, N W; Snijders, T A

    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 national bank in the Netherlands. Results suggest that job demands and job control should be conceptualized as having both group- and individual-level foundations. Support for Karasek's demands-control model was found only when these variables were split into the 2 parts, reflecting shared perceptions and employees' subjective assessment, respectively. One of the most appealing practical implications is that absence rates among homogeneous work groups can be reduced by enhancing actual control on the job.

  12. 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...

  13. Provision of secondary frequency control via demand response activation on thermostatically controlled loads: Solutions and experiences from Denmark

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Hu, Junjie;

    2016-01-01

    of household fridge performance in terms of response time and ramp-up rate, as well as the impact on fridge temperature and behaviour after the control period. The experimental results show that TCLs are fast responsive loads for DR activation, with the average control signal response time of 24 s......This paper studies the provision of secondary frequency control in electric power systems based on demand response (DR) activation on thermostatically controlled loads (TCLs) and quantifies the computation resource constraints for the control of large TCL population. Since TCLs are fast responsive...

  14. Decision Support for effective production control

    DEFF Research Database (Denmark)

    Africa, E.; Nehzati, T.; Strandhagen, J.O.;

    2012-01-01

    This study aims to identify the actual needs of decision makers for decision support in the production control activity, considering the role and cognitive skills of human decision-makers in the decision-making process. Multiple case studies have been conducted in order to gain practical insights...

  15. Decision support system for nursing management control

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, C.J.

    1983-01-01

    A knowledge representation approach for expert systems supporting decision processes in business is proposed. A description of a knowledge representation schema using a logic programming metalanguage is described, then the role of such a schema in a management expert system is demonstrated through the problem of nursing management control in hospitals. 18 references.

  16. Distributed demand side management via smart appliances contributing to frequency control

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei-chen

    2015-01-01

    Nowadays renewable energy has become a trend for energy production but its variable nature has made balancing of demand and supply of the power grid difficult. Dynamic demand management using smart appliances is proposed to serve as a way that part of the regulation burden of balancing demand and supply is shifted to the demand side. However, if all appliances respond to the same frequency deviation, they may start to synchronize, causing large power overshoots and instability of the power grid. Therefore, the idea of implementing randomness into the frequency control of the appliances is proposed and this is what we call a stochastic approach. Simulators are built from scratch to model both scenarios. The effect of synchronization is analyzed and the parameters that can affect the synchronization are investigated. It has been found that the larger the contribution from the smart appliances to the power grid, the easier and faster the synchronization takes place. The stochastic approach solves the problem of synchronization and averages out the large power overshoot. However, the overall performance of stochastic operations is unacceptable due to the randomness in the operation though the mean and variance are as expected. More advanced feedback policies and schemes may be designed to achieve a better performance.

  17. Optical People Counting for Demand Controlled Ventilation: A Pilot Study of Counter Performance

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J.; Sullivan, Douglas

    2009-12-26

    This pilot scale study evaluated the counting accuracy of two people counting systems that could be used in demand controlled ventilation systems to provide control signals for modulating outdoor air ventilation rates. The evaluations included controlled challenges of the people counting systems using pre-planned movements of occupants through doorways and evaluations of counting accuracies when naive occupants (i.e., occupants unaware of the counting systems) passed through the entrance doors of the building or room. The two people counting systems had high counting accuracy accuracies, with errors typically less than 10percent, for typical non-demanding counting events. However, counting errors were high in some highly challenging situations, such as multiple people passing simultaneously through a door. Counting errors, for at least one system, can be very high if people stand in the field of view of the sensor. Both counting system have limitations and would need to be used only at appropriate sites and where the demanding situations that led to counting errors were rare.

  18. 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.

  19. 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.

  20. 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…

  1. 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…

  2. Can an Opportunity to Learn at Work Reduce Stress?: A Revisitation of the Job Demand-Control Model

    Science.gov (United States)

    Panari, Chiara; Guglielmi, Dina; Simbula, Silvia; Depolo, Marco

    2010-01-01

    Purpose: This paper aims to extend the stress-buffering hypothesis of the demand-control model. In addition to the control variable, it seeks to analyse the role of an opportunity for learning and development (L&D) in the workplace as a moderator variable between increased demands and need for recovery. Design/methodology/approach: A…

  3. Adjusting to Job Demands: The Role of Work Self-Determination and Job Control in Predicting Burnout

    Science.gov (United States)

    Fernet, Claude; Guay, Frederic; Senecal, Caroline

    2004-01-01

    This study examined the dynamic interplay among job demands, job control, and work self-determination in order to predict burnout dimensions. A three-way interaction effect was found between job demands, job control and work self-determination in predicting each dimension of burnout (emotional exhaustion, depersonalization, and personal…

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

    Science.gov (United States)

    Chassin, David P.; Donnelly, Matthew K.; Dagle, Jeffery E.

    2006-12-12

    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.

  5. Role-based access control through on-demand classification of electronic health record.

    Science.gov (United States)

    Tiwari, Basant; Kumar, Abhay

    2015-01-01

    Electronic health records (EHR) provides convenient method to exchange medical information of patients between different healthcare providers. Access control mechanism in healthcare services characterises authorising users to access EHR records. Role Based Access Control helps to restrict EHRs to users in a certain role. Significant works have been carried out for access control since last one decade but little emphasis has been given to on-demand role based access control. Presented work achieved access control through physical data isolation which is more robust and secure. We propose an algorithm in which selective combination of policies for each user of the EHR database has been defined. We extend well known data mining technique 'classification' to group EHRs with respect to the given role. Algorithm works by taking various roles as class and defined their features as a vector. Here, features are used as a Feature Vector for classification to describe user authority.

  6. 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.

  7. Proposing an Algorithm for R&Q Inventory Control Model with Stochastic Demand Influenced by Shortage

    Directory of Open Access Journals (Sweden)

    Parviz fattahi

    2013-08-01

    Full Text Available In this article, the continuous - review inventory control system has been studied. A new constraint of demand dependent on the average percent of product shortage has been added to the problem. It means that the average demand has a direct relationship with shortage in a period. This constraint, which is related to the costs of credit loss of the organization due to product shortage, has been considered in the inventory model. In this paper, the mathematical model of this problem has been presented and then, two heuristic approaches based on the genetic and simulated annealing algorithms are developed. Computational results indicate that the simulated annealing algorithm can provide better results compare to the genetic algorithm.

  8. Demand Response Control in Low Voltage Grids for Technical and Commercial Aggregation Services

    DEFF Research Database (Denmark)

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

    2016-01-01

    hand, some of those represent a source of flexibility which can be used to satisfy different technical and commercial purposes. This paper introduces an upgraded hierarchical structure which aims to serve as a platform for activating and controlling the demand response in low voltage networks....... In this way, a system operator playing a role of an aggregator not only could trade flexible demand in the power markets but also materialize its energy agreements while ensuring the local network security and reliability. To verify the effectiveness of this extended method, a Danish low voltage networks...... is considered. The results show that it is possible to fulfill energy commitments in energy markets such as the regulation power market while respecting the proper network operation. However, the activation of the flexibility offered might be limited depending on the network characteristics and the season...

  9. 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.

  10. Killing Two Birds with One Stone: Can Real-Time Pricing SupportRetail Competition and Demand Response?

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen; Bharvirkar, Ranjit; Goldman, Charles; Hopper,Nicole; Neenan, Bernie

    2006-04-25

    As retail choice states reach the end of their transitional, rate-cap periods, state regulators must decide what type of default supply service to provide to customers that have not switched to a competitive retail supplier. In a growing number of states, regulators have adopted real-time pricing (RTP) as the default service for large commercial and industrial (C&I) customers. Although this trend is driven chiefly by policy objectives related to retail competition, default service RTP may have the added benefit of stimulating demand response. To evaluate the potential role of RTP as a means to both ends--retail market development and demand response--we conducted a comprehensive review of experience with default RTP in the U.S. and examined the emergence of RTP as a product offering by competitive retail suppliers. Across the ten utilities with default RTP in place in 2005, between 5% and 35% of the applicable load remained on the rate. Based on interviews with competitive retailers, we find evidence to suggest that a comparable amount of load in these states has switched to hourly pricing arrangements with competitive retailers. Many customers on default or competitive hourly pricing are paying prices indexed to the real-time spot market, and thus have no advance knowledge of prices. Because the price responsiveness of customers under these conditions has yet to be formally analyzed, and relatively few efforts have been undertaken to help these customers become price responsive, the actual demand response impacts from hourly pricing in retail choice states remains largely an open question. However, we find that policymakers and other stakeholders in retail choice states have various strategies at their disposal to capture the potential demand response benefits from hourly pricing, while simultaneously supporting retail competition.

  11. 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.

  12. 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.

  13. 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.

  14. 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

    Energy Technology Data Exchange (ETDEWEB)

    Dornburg, V.; Faaij, A.; Verweij, P. [Utrecht University, Utrecht (Netherlands); Banse, M.; Van Diepen, K.; Van Keulen, H.; Langeveld, H.; Meeusen, M.; Van de Ven, G.; Wester, F. [Wageningen UR, Wageningen (Netherlands); Alkemade, R.; Ten Brink, B.; Van den Born, G.J.; Van Oorschot, M.; Ros, J.; Smout, F.; Van Vuuren, D.; Van den Wijngaart, R. [Netherlands Environmental Assessment Agency NMP, Bilthoven (Netherlands); Aiking, H. [Vrije Universiteit, Amsterdam (Netherlands); Londo, M.; Mozaffarian, H.; Smekens, K. [ECN Policy Studies, Petten (Netherlands); Lysen, E. (ed.); Van Egmond, S. (ed.) [Utrecht Centre for Energy research UCE, Utrecht University, Utrecht (Netherlands)

    2008-01-15

    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.

  15. Software Support during a Control Room Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Michele Joyce; Michael Spata; Thomas Oren; Anthony Cuffe; Theo McGuckin; Isadoro Carlino; C. Higgins; Harry Fanning; Matthew Bickley; Brian Bevins

    2005-09-21

    In 2004, after 14 years of accelerator operations and commissioning, Jefferson Lab renovated its main control room. Changes in technology and lessons learned during those 14 years drove the control room redesign in a new direction, one that optimizes workflow and makes critical information and controls available to everyone in the control room. Fundamental changes in a variety of software applications were required to facilitate the new operating paradigm. A critical component of the new control room design is a large-format video wall that is used to make a variety of operating information available to everyone in the room. Analog devices such as oscilloscopes and function generators are now displayed on the video wall through two crosspoint switchers: one for analog signals and another for video signals. A new software GUI replaces manual configuration of the oscilloscopes and function generators and helps automate setup. Monitoring screens, customized for the video wall, now make important operating information visible to everyone, not just a single operator. New alarm handler software gives any operator, on any workstation, access to all alarm handler functionality, and multiple users can now contribute to a single electronic logbook entry. To further support the shift to distributed access and control, many applications have been redesigned to run on servers instead of on individual workstations.

  16. Design and Co-simulation of Hierarchical Architecture for Demand Response Control and Coordination

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Lévesque, Martin; Bak-Jensen, Birgitte

    2017-01-01

    Demand response (DR) plays a key role for optimum asset utilization and to avoid or delay the need of new infrastructure investment. However, coordinated execution of multiple DRs is desired to maximize the DR benefits. In this study, we propose a hierarchical DR architecture (HDRA) to control...... and coordinate the performance of various DR categories such that the operation of every DR category is backed-up by time delayed action of the others. A reliable, cost-effective communication infrastructure based on ZigBee, WiMAX, and fibers is designed to facilitate the HDRA execution. The performance...

  17. 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

    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...... 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...

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

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    is modelled to investigate the dynamic behaviour of DFR. Two DFR control logics, designed according to different appliance features, are implemented into the heat pump model. In this study, DFR acts as both disturbance and normal operation reserves to fulfill the requirement of frequency reserve by Danish......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...

  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. 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.

  1. 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.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    Andrea Prochnow

    2013-12-01

    Full Text Available OBJECTIVE: to evaluate the association between psychological demands, control over the work and the reduction of work ability of nursing professionals. METHOD: 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. RESULTS: 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. CONCLUSION: 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.

  4. 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.

  5. Does High Emotional Demand with Low Job Control Relate to Suicidal Ideation among Service and Sales Workers in Korea?

    Science.gov (United States)

    Yoon, Jin-Ha; Jeung, Dayee; Chang, Sei-Jin

    2016-07-01

    We examined the relationship of high emotional demands and low job control to suicidal ideation among service and sales workers in Korea. A total of 1,995 service and sales workers participated in this study. Suicidal ideation and level of emotional demand and job control were assessed by self-reported questionnaire in 4th Korean National Health and Nutrition Examination Survey. Gender-specific odds ratio (OR) and 95% confidence intervals (95% CI) for suicidal ideation were calculated using logistic regression analysis. The results show that workers who suffered from high emotional demands (OR, 2.07; 95% CI, 1.24-3.45 in men, OR, 1.97; 95% CI, 1.42-2.75 in women) or low job control (OR, 1.96; 95% CI, 1.42-2.75 in men, OR, 1.33; 95% CI, 0.91-1.93 in women) were more likely to experience suicidal ideation after controlling for age, household income, and employment characteristics. The interaction model of emotional demands and job control revealed that workers with high emotional demands and high job control (OR, 1.93; 95% CI, 1.08-3.45 in men, OR, 1.60; 95% CI,1.06-2.42 in women) and high emotional demands and low job control (OR; 4.60, 95% CI;1.88-11.29 in men, OR; 2.78, 95% CI;1.64-4.44 in women) had a higher risk for suicidal ideation compared to those with low emotional demands and high job control after controlling for age, household income, employment characteristics, smoking, alcohol drinking and physical activity habit. These results suggest that high emotional demands in both genders and low job control in men might play a crucial role in developing suicidal ideation among sales and service workers in Korea.

  6. ACRR: Ad Hoc On-Demand Distance Vector Routing with Controlled Route Requests

    CERN Document Server

    Kataria, Jayesh; Sanyal, Sugata

    2010-01-01

    Reactive routing protocols like Ad Hoc On-Demand Distance Vector Routing (AODV) and Dynamic Source Routing (DSR)in Ad-Hoc Wireless Networks which are used in Mobile and Ad Hoc Networks (MANETs) work by flooding the network with control packets. There is generally a limit on the number of these packets that can be generated or forwarded. But a malicious node can disregard this limit and flood the network with fake control packets. These packets hog the limited bandwidth and processing power of genuine nodes in the network while being forwarded. Due to this, genuine route requests suffer and many routes either do not get a chance to materialize or they end up being longer than otherwise. In this paper we propose a non cryptographic solution to the above problem and prove its efficiency by means of simulation.

  7. Inventory of the application of and the demand for Operations Support Systems (OSS) in the Netherlands energy production sector. Inventarisatie van het gebruik van en de behoefte aan Operations Support Systemen (OSS'en) in de E-produktiesector

    Energy Technology Data Exchange (ETDEWEB)

    De Ruijter, J.A.F. (KEMA Procesautomatisering en Informatietechnologie, Arnhem (Netherlands))

    1993-01-01

    Operation Support Systems (OSS) can contribute to the improvement of the efficiency of the energy production. Based on the results of interviews with experts in the field of electric power generation the title subject has been studied, focusing on process informative OSSs. Most of the electric power producers apply process informative OSSs for efficiency control of one whole unit and, if present, the gas turbine sub-system. Often, also a system to control the service life of the boiler and/or drum is applied. The main demand concerns on-line condition control, aimed at the thermodynamic performance of sub-installations (in particular gas turbines and condensers) on the one hand and at the technical condition of large components in relation to predictive maintenance on the other hand. There is also a need for an expert system by which operators can be advised to optimize the energy production process

  8. 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.

  9. 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 (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.

  10. Optimal Inventory Control Problem with Inflation-Dependent Demand Rate Under Stochastic Conditions

    Directory of Open Access Journals (Sweden)

    A. Mirzazadeh

    2012-02-01

    Full Text Available The practical experiences reveal that the Supply Chain Management (SCM is under uncertain and variable conditions. One of the most important parts of SCM is inventory system management which is inherently in non-deterministic situation. The many departments of organization such as warehouse, marketing, sale, purchasing, financial, planning, production, maintenance and etc. are relevance to the inventory problem. Since 1975 a series of related papers appeared that considered the effects of inflation on the inventory system. There are a few works in the inflationary inventory researches under stochastic conditions, especially with multiple stochastic parameters. Therefore, a new mathematical model for the optimal production for an inventory control system is formulated under stochastic environment. The demand rate is a function of inflation and time value of money where the inflation and time horizon i.e., period of business, both are random in nature. In the real situation, some but not all customers will wait for backlogged items during a shortage period, such as for fashionable commodities or high-tech products. Thus, the model incorporates partial backlogging. A numerical method has been used and the numerical example has been provided for evaluation and validation of the theoretical results and some special cases of the model are discussed. The results show the importance of taking into account stochastic inflation, time horizon and demand.

  11. 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.

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

    Science.gov (United States)

    1984-05-01

    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...1238 Aug 1 1236 1237 52 1074 1126 50 1033 1083 Sep 8 8 5W 862 7T 600 678 75 603 7r Oct 51 400 451 119 204 323 115 207 322 ov 64 123 287 187 71 258

  13. 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

    ) for future smart grid, based on the Islanding Security Region (ISR) concept. With the ISR, system operators can assess beforehand if an island operation can be successful for a given distribution system at its current operating state. In case of unfavorable assessment, control measures will be suggested...... to coordinate different resources, aiming at pulling the system back into the ISR to ensure a successful island operation on time....

  14. Environmental Control and Life Support System Mockup

    Science.gov (United States)

    2001-01-01

    The Environmental Control and Life Support System (ECLSS) Group of the Flight Projects Directorate at the Marshall Space Flight Center in Huntsville, Alabama, is responsible for designing and building the life support systems that will provide the crew of the International Space Station (ISS) a comfortable environment in which to live and work. This photograph shows the mockup of the the ECLSS to be installed in the Node 3 module of the ISS. From left to right, shower rack, waste management rack, Water Recovery System (WRS) Rack #2, WRS Rack #1, and Oxygen Generation System (OGS) rack are shown. The WRS provides clean water through the reclamation of wastewaters and is comprised of a Urine Processor Assembly (UPA) and a Water Processor Assembly (WPA). The UPA accepts and processes pretreated crewmember urine to allow it to be processed along with other wastewaters in the WPA. The WPA removes free gas, organic, and nonorganic constituents before the water goes through a series of multifiltration beds for further purification. The OGS produces oxygen for breathing air for the crew and laboratory animals, as well as for replacing oxygen loss. The OGS is comprised of a cell stack, which electrolyzes (breaks apart the hydrogen and oxygen molecules) some of the clean water provided by the WRS, and the separators that remove the gases from the water after electrolysis.

  15. 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.

  16. 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

  17. 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

  18. 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.

  19. Hydraulic demand characteristics of self-supported C-IV-N and K-I-N I&E fuel elements in a zirconium C-Reactor tube

    Energy Technology Data Exchange (ETDEWEB)

    Waters, E.D.

    1960-01-13

    This report discusses the isothermal hydraulic demand characteristics were determined by laboratory experiment for full charges of self-supported I&E fuel elements in a zirconium process tube. Pressure drop, flow rate data, and the calculations of annulus-to-hole flow ratio are presented. For self-supported fuel elements, pressure drop does not vary with temperature as much as it dies for non-self-supported furl elements.

  20. 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

  1. Optimal Ozone Control with Inclusion of Spatiotemporal Marginal Damages and Electricity Demand.

    Science.gov (United States)

    Mesbah, S Morteza; Hakami, Amir; Schott, Stephan

    2015-07-07

    Marginal damage (MD), or damage per ton of emission, is a policy metric used for effective pollution control and reducing the corresponding adverse health impacts. However, for a pollutant such as NOx, the MD varies by the time and location of the emissions, a complication that is not adequately accounted for in the currently implemented economic instruments. Policies accounting for MD information would aim to encourage emitters with large MDs to reduce their emissions. An optimization framework is implemented to account for NOx spatiotemporal MDs calculated through adjoint sensitivity analysis and to simulate power plants' behavior under emission and simplified electricity constraints. The results from a case study of U.S. power plants indicate that time-specific MDs are high around noon and low in the evening. Furthermore, an emissions reduction of about 40% and a net benefit of about $1200 million can be gained for this subset of power plants if a larger fraction of the electricity demand is supplied by power plants at low-damage times and in low-damage locations. The results also indicate that the consideration of temporal effects in NOx control policies results in a comparable net benefit to the consideration of spatial or spatiotemporal effects, thus providing a promising option for policy development.

  2. 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.

  3. 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 < usual after exposure to the intervention. The magnitude of the intervention's positive effect on 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.

  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.

    Science.gov (United States)

    Van de Ven, Bart; van den Tooren, Marieke; Vlerick, Peter

    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, and proposed that this relation is weakened by the availability of emotional job resources. Furthermore, it was hypothesized that this stress-buffer effect of emotional job resources would be stronger for employees high on emotional support seeking (3-way interaction). A 2-wave survey study with a 1-year time lag was conducted among 711 employees in the technology sector. Results showed that emotional job demands are least likely to result in emotional exhaustion when employees are provided with high emotional job resources and score high on emotional support seeking. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  5. Testing Karasek's Demands-Control Model in restructured healthcare settings: effects of job strain on staff nurses' quality of work life.

    Science.gov (United States)

    Laschinger, H K; Finegan, J; Shamian, J; Almost, J

    2001-05-01

    Job strain among staff nurses has become an increasingly important concern in relationship to employee performance and commitment to the organization in current restructured healthcare settings. The purpose of this study was to test Karasek's Demands-Control Model of job strain by examining the extent to which the degree of job strain in nursing work environments affects staff nurses' perceptions of structural and psychological empowerment, work satisfaction, and organizational commitment. A predictive, nonexperimental design was used to test these relationships in a random sample of 404 Canadian staff nurses. Karasek's Job Content Questionnaire, the Conditions of Work Effectiveness Questionnaire-II, Spreitzer's Psychological Empowerment Questionnaire, Meyer and Allen's Organizational Commitment Questionnaire, and the Global Satisfaction Scale were used to measure the major study variables. Nurses with higher level of job strain were found to be significantly more empowered, more committed to the organization, and more satisfied with their work. Support for Karasek's Demands/Control theory was established in this study.

  6. Environmental Control and Life Support Systems

    Science.gov (United States)

    Engel, Joshua Allen

    2017-01-01

    The Environmental Control System provides a controlled air purge to Orion and SLS. The ECS performs this function by processing 100% ambient air while simultaneously controlling temperature, pressure, humidity, cleanliness and purge distribution.

  7. 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 lo

  8. Optimal Control of Production-Inventory Systems with Constant and Compound Poisson Demand

    NARCIS (Netherlands)

    Germs, Remco; Foreest, Nicky D. van

    2014-01-01

    In this paper, we study a production-inventory systems with finite production capacity and fixed setup costs. The demand process is modeled as a mixture of a compound Poisson process and a constant demand rate. For the backlog model we establish conditions on the holding and backlogging costs such

  9. 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.

  10. [Work-related stress according to the Demand-Control Model and Minor Psychic Disorder in nursing workers].

    Science.gov (United States)

    Urbanetto, Janete de Souza; Magalhães, Maria Cristina Cademartori; Maciel, Vanessa Oreda; Sant'Anna, Viviane Massena; Gustavo, Andréia da Silva; Poli-de-Figueiredo, Carlos Eduardo; Magnago, Tânia Solange Bosi de Souza

    2013-10-01

    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.

  11. Forecasting Water Demand in Residential, Commercial, and Industrial Zones in Bogotá, Colombia, Using Least-Squares Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Carlos Peña-Guzmán

    2016-01-01

    Full Text Available The Colombian capital, Bogotá, has undergone massive growth in a short period of time. Naturally, this growth has increased the city’s water demand. The prediction of this demand will help understand and analyze consumption behavior, thereby allowing for effective management of the urban water cycle. This paper uses the Least-Squares Support Vector Machines (LS-SVM model for forecasting residential, industrial, and commercial water demand in the city of Bogotá. The parameters involved in this study include the following: monthly water demand, number of users, and total water consumption bills (price for the three studied uses. Results provide evidence of the model’s accuracy, producing R2 between 0.8 and 0.98, with an error percentage under 12%.

  12. On Demand Runs Of Mesoscale Models : Météo-France multi-mission, multi-support GUI

    Science.gov (United States)

    Periard, C.; Pourret, V.; Chaupin, D.

    2009-09-01

    Numerous experiment campaigns have shown the interest of mesoscale models to represent weather conditions of the atmosphere as a support to various applications, from electromagnetic propagation to wind power atlas. However running mesoscale models requires high level knowledge on computing and modelling to define the different parameters for a given simulation. With the increase of the demands for mesoscale simulations, we decided to develop a GUI that enables to easily define and run type-experiments Ø at any location on the globe Ø on different types of computers (from Meteo-France Fujitsu to a PC Cluster) Ø with different choices of forcing models. The GUI developed in PHP, uses a map server to visualize the location of the experiment being defined and the different forcing models available for the simulation. The other parameters such as time steps, resolutions, sizes and number of embedded domains, etc … can be modified through checkboxes or multiple choices lists in the GUI. So far, the GUI has been used to run 3 different types of experiment : Ø for EM propagation purpose, during an experiment campaign near Toulon : the simulations were run on a PC Cluster in analyse mode. Ø for wind profiles prediction, in Afghanistan : the simulations are run on the Fujitsu in forecast mode. Ø for weather forecast, during a the F1 race in Japan : the simulations were run on a PC Cluster in forecast mode. During the presentation, I will first give some screen-prints of the different fill-in forms of the Gui and the way to define an experiment. Then I will focus on the 3 examples mentioned above showing different types of graphs and maps produced. There are tons of other applications where this tool is going to be useful especially in climatology: using weather type classification and downscaling, the Gui will help run the simulations of the different clusters representatives . The last thing to accomplish is find a name for the tool.

  13. 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....

  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. 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.

  16. 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.

    2016-01-01

    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. PMID:27275828

  17. 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.

  18. 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...... 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...

  19. Developing a Toolset Supporting the Construction of Reusable Components for Embedded Control Systems

    DEFF Research Database (Denmark)

    Guan, Wei; Sierszecki, Krzysztof; Angelov, Christo K.

    2010-01-01

    Reusing software components for embedded control applications enhances product quality and reduces time to market when appropriate (formal) methodologies and supporting toolsets are available. That is why industrial companies are interested in developing trusted, in-house reusable components....... That demand can be satisfied by a highly customized toolset providing an integrated development environment for rapid graphical component specification, component validation, automatic generation of artifacts and documentation. The paper presents a possible solution for creating a customized toolset based...... on open-source technology, in accordance with industrial requirements, as well as the approach used to engineer a toolset supporting component development for embedded control applications....

  20. Natural Oxidant Demand Variability, Potential Controls, and Implications for in Situ, Oxidation-Based Remediation of Contaminated Groundwater

    Science.gov (United States)

    Dettmer, A.; Cruz, S.; Dungan, B.; Holguin, F. O.; Ulery, A. L.; Hunter, B.; Carroll, K. C.

    2014-12-01

    Naturally occurring reduced species associated with subsurface materials can impose a significant natural oxidant demand (NOD), which is the bulk consumption of oxidants by soil water, minerals, and organic matter. Although injection of oxidants has been used for chemical transformation of organic contaminants, NOD represents a challenge for the in-situ delivery of oxidants as a remediation alternative. Co-injection of complexation agents with oxidants has been proposed to facilitate the delivery of oxidants for in situ chemical oxidation remediation of contaminated groundwater. This study investigates variability of NOD for different oxidants and sediments. The effect of the addition of various complexation agents, including EDTA, tween 80, hydroxypropyl-beta-cyclodextrin (HPCD), humic acid, and four generations of poly(amidoamine) (PAMAM) dendrimers, on the NOD was also examined. NOD was measured for a clay loam (collected from Air Force Plant 44 in Tucson, AZ). Varying amounts of biosolids were mixed with subsamples of the clay loam to create three additional reference soils in order to study the effect of organic matter and other soil characteristics on the NOD. Bench-scale laboratory experiments were conducted to determine the NOD for various oxidants, using the four soils, and replicated with and without various delivery agents. Measured NOD showed variability for each soil and oxidant composition. Additionally, significant differences were observed in NOD with the addition of delivery agents. The results support the elucidation of potential controls over NOD and have implications for in situ, oxidation-based remediation of contaminated groundwater.

  1. Determinants of parental support for governmental alcohol control policies

    NARCIS (Netherlands)

    Hoof, van Joris J.; Gosselt, Jordy F.; Jong, de Menno D.T.

    2010-01-01

    Aim: To explore determinants that predict parental support for governmental alcohol control policies in the Netherlands. Method: A questionnaire was administered among 1550 parents, containing six possible predictors to explain support for alcohol control policies. Results: Parental support can be e

  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. Tagging behaviour with support from controlled vocabulary

    DEFF Research Database (Denmark)

    Lykke, Marianne; Høj, Anne Lyhne; Madsen, Line Nørgaard

    2011-01-01

    The paper investigates how knowledge structures from a controlled vocabulary affect tagging. The study is a comparative analysis of tags assigned in two tagging systems, a simple tagging system (control system) that provides suggestions from two tag clouds (all users tags and my tags) and an enha...

  4. Supporting dimensional control by information technology

    NARCIS (Netherlands)

    Wu, R.; Berends, G.; Hoof, P. van; Maas, G.; Tolman, F.P.

    1998-01-01

    In the building industry, there is a necessity of designing the dimensional control plan before starting construction, for the assurance of the defined dimensional quality. The dimensional control plan provides site personnel with information on, among others, setting out and assembling building com

  5. 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…

  6. 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...

  7. Reach a New Threshold of Freedom and Control with Dell's Flexible Computing Solution: On-Demand Desktop Streaming

    Science.gov (United States)

    Technology & Learning, 2008

    2008-01-01

    When it comes to IT, there has always been an important link between data center control and client flexibility. As computing power increases, so do the potentially crippling threats to security, productivity and financial stability. This article talks about Dell's On-Demand Desktop Streaming solution which is designed to centralize complete…

  8. Reach a New Threshold of Freedom and Control with Dell's Flexible Computing Solution: On-Demand Desktop Streaming

    Science.gov (United States)

    Technology & Learning, 2008

    2008-01-01

    When it comes to IT, there has always been an important link between data center control and client flexibility. As computing power increases, so do the potentially crippling threats to security, productivity and financial stability. This article talks about Dell's On-Demand Desktop Streaming solution which is designed to centralize complete…

  9. Poor impulse control predicts inelastic demand for nicotine but not alcohol in rats.

    Science.gov (United States)

    Diergaarde, Leontien; van Mourik, Yvar; Pattij, Tommy; Schoffelmeer, Anton N M; De Vries, Taco J

    2012-05-01

    Tobacco and alcohol dependence are characterized by continued use despite deleterious health, social and occupational consequences, implying that addicted individuals pay a high price for their use. In behavioral economic terms, such persistent consumption despite increased costs can be conceptualized as inelastic demand. Recent animal studies demonstrated that high-impulsive individuals are more willing to work for nicotine or cocaine infusions than their low-impulsive counterparts, indicating that this trait might be causally related to inelastic drug demand. By employing progressive ratio schedules of reinforcement combined with a behavioral economics approach of analysis, we determined whether trait impulsivity is associated with an insensitivity of nicotine or alcohol consumption to price increments. Rats were trained on a delayed discounting task, measuring impulsive choice. Hereafter, high- and low-impulsive rats were selected and trained to nose poke for intravenous nicotine or oral alcohol. Upon stable self-administration on a continuous reinforcement schedule, the price (i.e. response requirement) was increased. Demand curves, depicting the relationship between price and consumption, were produced using Hursh's exponential demand equation. Similar to human observations, nicotine and alcohol consumption in rats fitted this equation, thereby demonstrating the validity of our model. Moreover, high-impulsive rats displayed inelastic nicotine demand, as their nicotine consumption was less sensitive to price increments as compared with that in low-impulsive rats. Impulsive choice was not related to differences in alcohol demand elasticity. Our model seems well suited for studying nicotine and alcohol demand in rats and, as such, might contribute to our understanding of tobacco and alcohol dependence. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.

  10. Controlled Ecological Life Support System. Life Support Systems in Space Travel

    Science.gov (United States)

    Macelroy, R. D. (Editor); Smernoff, D. T. (Editor); Klein, H. P. (Editor)

    1985-01-01

    Life support systems in space travel, in closed ecological systems were studied. Topics discussed include: (1) problems of life support and the fundamental concepts of bioregeneration; (2) technology associated with physical/chemical regenerative life support; (3) projection of the break even points for various life support techniques; (4) problems of controlling a bioregenerative life support system; (5) data on the operation of an experimental algal/mouse life support system; (6) industrial concepts of bioregenerative life support; and (7) Japanese concepts of bioregenerative life support and associated biological experiments to be conducted in the space station.

  11. The impact of indoor thermal conditions, system controls and building types on the building energy demand

    Energy Technology Data Exchange (ETDEWEB)

    Corgnati, Stefano Paolo; Fabrizio, Enrico; Filippi, Marco [Dipartimento di Energetica (DENER), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy)

    2008-07-01

    It is possible to evaluate the energy demand as well as the parameters related to indoor thermal comfort through building energy simulation tools. Since energy demand for heating and cooling is directly affected by the required level of thermal comfort, the investigation of the mutual relationship between thermal comfort and energy demand (and therefore operating costs) is of the foremost importance both to define the benchmarks for energy service contracts and to calibrate the energy labelling according to European Directive 2002/92/CE. The connection between indoor thermal comfort conditions and energy demand for both heating and cooling has been analyzed in this work with reference to a set of validation tests (office buildings) derived from a European draft standard. Once a range of required acceptable indoor operative temperatures had been fixed in accordance with Fanger's theory (e.g. -0.5 < PMV < -0.5), the effective hourly comfort conditions and the energy consumptions were estimated through dynamic simulations. The same approach was then used to quantify the energy demand when the range of acceptable indoor operative temperatures was fixed in accordance with de Dear's adaptive comfort theory. (author)

  12. 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.

  13. Tagging behaviour with support from controlled vocabulary

    DEFF Research Database (Denmark)

    Lykke, Marianne; Høj, Anne Lyhne; Madsen, Line Nørgaard

    2011-01-01

    The paper investigates how knowledge structures from a controlled vocabulary affect tagging. The study is a comparative analysis of tags assigned in two tagging systems, a simple tagging system (control system) that provides suggestions from two tag clouds (all users tags and my tags) and an enha......The paper investigates how knowledge structures from a controlled vocabulary affect tagging. The study is a comparative analysis of tags assigned in two tagging systems, a simple tagging system (control system) that provides suggestions from two tag clouds (all users tags and my tags...... vocabulary might help taggers in being more specific in their tagging, allowing more precise information searching based on user tags. In addition, the results indicate that structured controlled suggestions might encourage taggers to add synonym variations enhancing the variety and number of access points....... Furthermore, controlled vocabularies might be useful for automatic spell checking. Future study should explore in what direction the different kinds of suggestions lead the tagger and whether it is possible to identify scope or patterns between related tags from the two systems....

  14. 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...

  15. 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

    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 conventio......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...... conventionally has been the temperature or the CO2-concentration. When compared to schedule driven ventilation, application of DCV can lead to substantial energy savings. However, CO2 is the pollutant related to human occupancy and it does not provide any indication of so called building-related pollution...... 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...

  16. 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.

  17. 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

    2015-03-01

    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.

  18. 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

    2015-10-01

    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.

  19. Overview of NASA's Environmental Control and Life Support Systems

    Science.gov (United States)

    Roman, Monserrate

    2009-01-01

    This viewgraph presentation reviews NASA's Environmental Control and Life Support Systems (ECLSS) on the International Space Station. A look inside of the International Space Station detailing ECLSS processes of controlling atmospheric pressure, conditioning the atmosphere, responding to emergency conditions, controlling internal carbon dioxide and contaminants and providing water are described. A detailed description of ISS Regenerative Environmental Control and Life Support System is also presented.

  20. Controlling the stream of thought: working memory capacity predicts adjustment of mind-wandering to situational demands.

    Science.gov (United States)

    Rummel, Jan; Boywitt, C Dennis

    2014-10-01

    Although engaging in task-unrelated thoughts can be enjoyable and functional under certain circumstances, allowing one's mind to wander off-task will come at a cost to performance in many situations. Given that task-unrelated thoughts need to be blocked out when the current task requires full attention, it has been argued that cognitive control is necessary to prevent mind-wandering from becoming maladaptive. Extending this idea, we exposed participants to tasks of different demands and assessed mind-wandering via thought probes. Employing a latent-change model, we found mind-wandering to be adjusted to current task demands. As hypothesized, the degree of adjustment was predicted by working memory capacity, indicating that participants with higher working memory capacity were more flexible in their coordination of on- and off-task thoughts. Notably, the better the adjustment, the smaller performance decrements due to increased task demands were. On the basis of these findings, we argue that cognitive control does not simply allow blocking out task-unrelated thoughts but, rather, allows one to flexibly adjust mind-wandering to situational demands.

  1. Job Demands and Job Control as Predictors of Depressive Symptoms: Moderating Effects of Negative Childhood Socioemotional Experiences.

    Science.gov (United States)

    Pulkki-Råback, Laura; Elovainio, Marko; Virtanen, Marianna; Kivimäki, Mika; Hintsanen, Mirka; Hintsa, Taina; Jokela, Markus; Puttonen, Sampsa; Joensuu, Matti; Lipsanen, Jari; Raitakari, Olli T; Keltikangas-Järvinen, Liisa

    2016-10-01

    There have been calls to know more about vulnerability factors that may predispose to adverse health outcomes at work. We examined if childhood adverse experiences would affect vulnerability to psychosocial stress factors at work. A nationally representative sample of 1546 Finnish men and women was followed up from childhood to adulthood. Childhood adverse experiences consisted of socioeconomic and emotional factors. Job demands and job control were measured 21 years later, and depressive symptoms were measured 21 and 27 years after the childhood measurements. Job demands predicted depressive symptoms over 6 years, and the association was modified by childhood emotional adversity. Participants with three or more emotional adversities in childhood had more depressive symptoms in response to high job demands compared with participants with zero or one emotional adversities in childhood (Betas = -1.40 and -2.01, ps job control and depressive symptoms. Although modest in effect size, these findings provide a developmental viewpoint for understanding the role of childhood experiences in work-related stress factors. Such knowledge can enhance understanding of individual differences in vulnerability to the demands of working life. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Controlled ecological life support system - biological problems

    Science.gov (United States)

    Moore, B., III (Editor); Macelroy, R. D. (Editor)

    1982-01-01

    The general processes and controls associated with two distinct experimental paradigms are examined. Specific areas for research related to biotic production (food production) and biotic decomposition (waste management) are explored. The workshop discussions were directed toward Elemental cycles and the biological factors that affect the transformations of nutrients into food, of food material into waste, and of waste into nutrients were discussed. To focus on biological issues, the discussion assumed that (1) food production would be by biological means (thus excluding chemical synthesis), (2) energy would not be a limiting factor, and (3) engineering capacity for composition and leak rate would be adequate.

  3. 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

    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. 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. 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). 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.

  4. 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 ...

  5. 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.

  6. Final Scientific Technical Report: INTEGRATED PREDICTIVE DEMAND RESPONSE CONTROLLER FOR COMMERCIAL BUILDINGS

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, Mike

    2013-10-14

    This project provides algorithms to perform demand response using the thermal mass of a building. Using the thermal mass of the building is an attractive method for performing demand response because there is no need for capital expenditure. The algorithms rely on the thermal capacitance inherent in the building?s construction materials. A near-optimal ?day ahead? predictive approach is developed that is meant to keep the building?s electrical demand constant during the high cost periods. This type of approach is appropriate for both time-of-use and critical peak pricing utility rate structures. The approach uses the past days data in order to determine the best temperature setpoints for the building during the high price periods on the next day. A second ?model predictive approach? (MPC) uses a thermal model of the building to determine the best temperature for the next sample period. The approach uses constant feedback from the building and is capable of appropriately handling real time pricing. Both approaches are capable of using weather forecasts to improve performance.

  7. 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

  8. Recommended Changes to Specifications for Demand Controlled Ventilation in California's Title 24 Building Energy Efficiency Standards

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-04-08

    In demand-controlled ventilation (DCV), rates of outdoor air ventilation are automatically modulated as occupant density varies. 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. DCV is most often used in spaces with highly variable and sometime dense occupancy. In almost all cases, carbon dioxide (CO{sub 2}) sensors installed in buildings provide the signal to the ventilation rate control system. People produce and exhale CO{sub 2} as a consequence of their normal metabolic processes; thus, the concentrations of CO{sub 2} inside occupied buildings are higher than the concentrations of CO{sub 2} in the outdoor air. The magnitude of the indoor-outdoor CO{sub 2} concentration difference decreases as the building's ventilation rate per person increases. The difference between the indoor and outdoor CO{sub 2} concentration is also a proxy for the indoor concentrations of other occupant-generated bioeffluents, such as body odors. Reviews of the research literature on DCV indicate a significant potential for energy savings, particularly in buildings or spaces with a high and variable occupancy. Based on modeling, cooling energy savings from applications of DCV are as high as 20%. With support from the California Energy Commission and the U.S. Department of Energy, the Lawrence Berkeley National Laboratory has performed research on the performance of CO{sub 2} sensing technologies and optical people counters for DCV. In addition, modeling was performed to evaluate the potential energy savings and cost effectiveness of using DCV in general office spaces within the range of California climates. The above-described research has implications for the specifications pertaining to DCV in section 121 of the California Title 24 Standard. Consequently, this document suggests possible changes in these specifications based on the research findings. The suggested

  9. Recommended Changes to Specifications for Demand Controlled Ventilation in California's Title 24 Building Energy Efficiency Standards

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-04-08

    In demand-controlled ventilation (DCV), rates of outdoor air ventilation are automatically modulated as occupant density varies. 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. DCV is most often used in spaces with highly variable and sometime dense occupancy. In almost all cases, carbon dioxide (CO{sub 2}) sensors installed in buildings provide the signal to the ventilation rate control system. People produce and exhale CO{sub 2} as a consequence of their normal metabolic processes; thus, the concentrations of CO{sub 2} inside occupied buildings are higher than the concentrations of CO{sub 2} in the outdoor air. The magnitude of the indoor-outdoor CO{sub 2} concentration difference decreases as the building's ventilation rate per person increases. The difference between the indoor and outdoor CO{sub 2} concentration is also a proxy for the indoor concentrations of other occupant-generated bioeffluents, such as body odors. Reviews of the research literature on DCV indicate a significant potential for energy savings, particularly in buildings or spaces with a high and variable occupancy. Based on modeling, cooling energy savings from applications of DCV are as high as 20%. With support from the California Energy Commission and the U.S. Department of Energy, the Lawrence Berkeley National Laboratory has performed research on the performance of CO{sub 2} sensing technologies and optical people counters for DCV. In addition, modeling was performed to evaluate the potential energy savings and cost effectiveness of using DCV in general office spaces within the range of California climates. The above-described research has implications for the specifications pertaining to DCV in section 121 of the California Title 24 Standard. Consequently, this document suggests possible changes in these specifications based on the research findings. The suggested

  10. Comparison of a Constant Air Volume (CAV) and a Demand Controlled Ventilation (DCV) System in a Residential Building

    DEFF Research Database (Denmark)

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

    2008-01-01

    The aim of this paper was to compare the indoor climate and the energy performance of a Constant Air Volume (CAV) system of 0.5h-1 with a Demand Controlled Ventilation (DCV) system controlled by occupancy and relative humidity for a studio apartment. Furthermore the impact of building materials...... hygroscopic properties on indoor climate and energy consumption was investigated for the two systems. Dynamic simulations of the studio apartment were carried out in the program WUFI+ with weather data from Copenhagen including outside temperature end relative humidity. For the non-hygroscopic case...

  11. 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

    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......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...... 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...

  12. 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.

  13. Insula Demonstrates a Non-Linear Response to Varying Demand for Cognitive Control and Weaker Resting Connectivity With the Executive Control Network in Smokers.

    Science.gov (United States)

    Fedota, John R; Matous, Allison L; Salmeron, Betty Jo; Gu, Hong; Ross, Thomas J; Stein, Elliot A

    2016-09-01

    Deficits in cognitive control processes are a primary characteristic of nicotine addiction. However, while network-based connectivity measures of dysfunction have frequently been observed, empirical evidence of task-based dysfunction in these processes has been inconsistent. Here, in a sample of smokers (n=35) and non-smokers (n=21), a previously validated parametric flanker task is employed to characterize addiction-related alterations in responses to varying (ie, high, intermediate, and low) demands for cognitive control. This approach yields a demand-response curve that aims to characterize potential non-linear responses to increased demand for control, including insensitivities or lags in fully activating the cognitive control network. We further used task-based differences in activation between groups as seeds for resting-state analysis of network dysfunction in an effort to more closely link prior inconsistencies in task-related activation with evidence of impaired network connectivity in smokers. For both smokers and non-smokers, neuroimaging results showed similar increases in activation in brain areas associated with cognitive control. However, reduced activation in right insula was seen only in smokers and only when processing intermediate demand for cognitive control. Further, in smokers, this task-modulated right insula showed weaker functional connectivity with the superior frontal gyrus, a component of the task-positive executive control network. These results demonstrate that the neural instantiation of salience attribution in smokers is both more effortful to fully activate and has more difficulty communicating with the exogenous, task-positive, executive control network. Together, these findings further articulate the cognitive control dysfunction associated with smoking and illustrate a specific brain circuit potentially responsible.

  14. Improvement of the analysis of the biochemical oxygen demand (BOD) of Mediterranean seawater by seeding control.

    Science.gov (United States)

    Simon, F Xavier; Penru, Ywann; Guastalli, Andrea R; Llorens, Joan; Baig, Sylvie

    2011-07-15

    Biochemical oxygen demand (BOD) is a useful parameter for assessing the biodegradability of dissolved organic matter in water. At the same time, this parameter is used to evaluate the efficiency with which certain processes remove biodegradable natural organic matter (NOM). However, the values of BOD in seawater are very low (around 2 mgO(2)L(-1)) and the methods used for its analysis are poorly developed. The increasing attention given to seawater desalination in the Mediterranean environment, and related phenomena such as reverse osmosis membrane biofouling, have stimulated interest in seawater BOD close to the Spanish coast. In this study the BOD analysis protocol was refined by introduction of a new step in which a critical quantity of autochthonous microorganisms, measured as adenosine triphosphate, is added. For the samples analyzed, this improvement allowed us to obtain reliable and replicable BOD measurements, standardized with solutions of glucose-glutamic acid and acetate. After 7 days of analysis duration, more than 80% of ultimate BOD is achieved, which in the case of easily biodegradable compounds represents nearly a 60% of the theoretical oxygen demand. BOD(7) obtained from the Mediterranean Sea found to be 2.0±0.3 mgO(2)L(-1) but this value decreased with seawater storage time due to the rapid consumption of labile compounds. No significant differences were found between two samples points located on the Spanish coast, since their organic matter content was similar. Finally, the determination of seawater BOD without the use of inoculum may lead to an underestimation of BOD.

  15. 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…

  16. 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…

  17. PERFUSION SYSTEM CONTROLLER STRATEGIES DURING AN ECMO SUPPORT

    OpenAIRE

    2014-01-01

    In this work modelling and control of Perfusion system is presented. The Perfusion system simultaneously controls the partial pressures during Extra Corporeal Membrane Oxygenation (ECMO) support. The main Problem in ECMO system is exchange of Blood Gases in the Artificial Lung (Oxygenator).It is a highly Nonlinear Process comprising time-varying parameters, and varying time delays, it is currently being controlled manually by trained Perfusionist. The new control strategy implemen...

  18. Integrated Control Strategies Supporting Autonomous Functionalities in Mobile Robots

    Science.gov (United States)

    2005-01-01

    Integrated Control Strategies Supporting Autonomous Functionalities in Mobile Robots B. Sightsa, H.R. Everetta, E. Biagtan Pacisa, G. Koguta M...TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Integrated Control Strategies Supporting Autonomous Functionalities in Mobile Robots 5a...calculation methods using encoder counts, wheel radius, and the robot’s wheelbase, as described in Sensors For Mobile Robots [5]. On top of this

  19. 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.

  20. Environmental topography and postural control demands shape aging-associated decrements in spatial navigation performance.

    Science.gov (United States)

    Lövdén, Martin; Schellenbach, Michael; Grossman-Hutter, Barbara; Krüger, Antonio; Lindenberger, Ulman

    2005-12-01

    This study tests the hypothesis that aging-induced cognitive permeation of sensorimotor functions contributes to adult age differences in spatial navigation performance. Virtual maze-like museums were projected in front of a treadmill. Sixteen 20-30-year-old men and sixteen 60-70-year-old men performed a way-finding task in city-block or variable topographies while walking with or without support. Walking support attenuated age-related decrements in navigational learning. Navigation load increased trunk-angle variability for older adults only. Age differences in spatial knowledge persisted despite perfect place-finding performance. City-block topography was easier than variable topography for younger adults only, indicating age-related differences in reliance on spatial relational learning. Attempts at supporting older adults' navigation performance should consider sensorimotor/cognitive interactions and qualitative differences in navigational activity. (c) 2006 APA

  1. Hierarchical Decentralized Control Strategy for Demand-Side Primary Frequency Response

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Jianming; Hansen, Jacob; Marinovici, Laurentiu D.; Kalsi, Karanjit

    2016-07-21

    The Grid Friendly$^\\textrm{TM}$ Appliance~(GFA) controller, developed at Pacific Northwest National Laboratory, was designed for the purpose of autonomously switching off appliances by detecting under-frequency events. In this paper, a new frequency responsive load~(FRL) controller is first proposed by extending the functionality of the original GFA controller. The proposed FRL controller can autonomously switch on (or off) end-use loads by detecting over-frequency (or under-frequency) events through local frequency measurement. Then, a hierarchical decentralized control framework is developed for engaging the end-use loads to provide primary frequency response with the proposed FRL controller. The developed framework has several important features that are desirable in terms of providing primary frequency control. It not only exclusively maintains the autonomous operation of the end-use loads, but also effectively overcomes the stability issue associated with high penetration of FRLs. The simulation results illustrate the effectiveness of the developed hierarchical control framework for providing primary frequency response with the proposed FRL controller.

  2. 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

    The performance of a model predictive controller (MPC) is highly correlated with the model's accuracy. This paper introduces an economic model predictive control (EMPC) scheme based on a nonlinear model, which uses a branch-and-bound tree search for solving the inherent non-convex optimization...... 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...

  3. 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.

  4. Age-related changes in dynamic postural control and attentional demands are minimally affected by local muscle fatigue.

    Directory of Open Access Journals (Sweden)

    Anthony eRemaud

    2016-01-01

    Full Text Available 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 and the medio-lateral axes, with and without the addition of a simple reaction time 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 plantarflexor 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. Reaction times 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, reaction time increased more in seniors when switching from static stance to dynamic postural conditions, suggesting potential alterations in the central nervous system 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.

  5. Energy Demand

    NARCIS (Netherlands)

    Stehfest, E. et al.

    2014-01-01

    Key policy issues – How will energy demand evolve particularly in emerging and medium- and low- income economies? – What is the mix of end-use energy carriers to meet future energy demand? – How can energy efficiency contribute to reducing the growth rate of energy demand and mitigate pressures on t

  6. Funds support the construction of control systems design

    Science.gov (United States)

    Vlasov, V.; Tolokonsky, A.

    2016-08-01

    The experience of the creation tools to support the construction of control systems design skills to provide effective training for students of the Department of Automation MEPhI, to create management information systems based on PCS. Currently the control system have been widely used not only in industry, but also on research. Therefore, quite important question of training in research automation.

  7. Management control of support services : The case of IT sourcing

    NARCIS (Netherlands)

    Lau, La E.; Laan, van der M.; Speklé, R.F.; Kruis, A.

    2009-01-01

    This paper provides evidence on the factors that influence the design of the control arrangements that govern support services. Based on TCE, we hypothesize that control structure choices depend on asset specificity, uncertainty, and frequency. Using survey data on IT sourcing decisions from 89 firm

  8. 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 in ...

  9. Robust optimal control of material flows in demand-driven supply networks

    Science.gov (United States)

    Laumanns, Marco; Lefeber, Erjen

    2006-04-01

    We develop a model based on stochastic discrete-time controlled dynamical systems in order to derive optimal policies for controlling the material flow in supply networks. Each node in the network is described as a transducer such that the dynamics of the material and information flows within the entire network can be expressed by a system of first-order difference equations, where some inputs to the system act as external disturbances. We apply methods from constrained robust optimal control to compute the explicit control law as a function of the current state. For the numerical examples considered, these control laws correspond to certain classes of optimal ordering policies from inventory management while avoiding, however, any a priori assumptions about the general form of the policy.

  10. 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.

  11. The Spartan attitude control system - Ground support computer

    Science.gov (United States)

    Schnurr, R. G., Jr.

    1986-01-01

    The Spartan Attitude Control System (ACS) contains a command and control computer. This computer is optimized for the activities of the flight and contains very little human interface hardware and software. The computer system provides the technicians testing of Spartan ACS with a convenient command-oriented interface to the flight ACS computer. The system also decodes and time tags data automatically sent out by the flight computer as key events occur. The duration and magnitude of all system maneuvers is also derived and displayed by this system. The Ground Support Computer is also the primary Ground Support Equipment for the flight sequencer which controls all payload maneuvers, and long term program timing.

  12. Controlled Dispensing and Mixing of Pico- to Nanoliter Volumes Using On-Demand Droplet-Based Microfluidics

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xuefei; Tang, Keqi; Smith, Richard D.; Kelly, Ryan T.

    2013-07-08

    We present an integrated droplet-on-demand microfluidic platform for dispensing, mixing, incubating, extracting and analyzing by mass spectrometry pico- to nanoliter sized droplets. Droplet generation is accomplished using computer-controlled pneumatic valves. Controlled actuation of valves for different aqueous streams enables controlled dosing and rapid mixing of reagents within droplets in the droplet generation area or in a region with widening channel cross-section. Following incubation, which takes place while droplets travel in the oil stream, the droplet contents are extracted to an aqueous channel for subsequent ionization at an integrated nanoelectrospray emitter. As an initial demonstration of the platform, rapid enzymatic digestions of a model protein are performed in droplets and detected on-line by nanoelectrospray ionization mass spectrometry.

  13. Automated drop-on-demand system with real-time gravimetric control for precise dosage formulation.

    Science.gov (United States)

    Sahay, A; Brown, M; Muzzio, F; Takhistov, Paul

    2013-04-01

    Many of the therapies for personalized medicine have few dosage options, and the successful translation of these therapies to the clinic is significantly dependent on the drug/formulation delivery platform. We have developed a lab-scale integrated system for microdosing of drug formulations with high accuracy and precision that is capable of feedback control. The designed modular drug dispensing system includes a microdispensing valve unit and is fully automated with a LabVIEW-controlled computer interface. The designed system is capable of dispensing drug droplets with volumes ranging from nanoliters to microliters with high accuracy (relative standard deviation gravimetric control.

  14. Towards automated solid phase radiofluorination for dose-on-demand PET: retention of activity by solid support

    DEFF Research Database (Denmark)

    Ingemann Mathiessen, Bente; Severin, Gregory; Zhuravlev, Fedor

    2015-01-01

    On-column [18F]fluoride trapping and radiofluorination of 2-(naphthalen-1-yl)ethyl-4-methylbenzenesulfonate (C10H7(CH2)2OTs), performed on polystyrene supported phosphazene base PS-PtBu2 yielded [18F]1-(2-fluoroethyl)naphthalene ([18F]C10H7(CH2)2F) in 50% radiochemical yield but left up to 43% of...

  15. Support vector regression-based internal model control

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan-wei; PENG Tie-gen

    2007-01-01

    This paper proposes a design of internal model control systems for process with delay by using support vector regression (SVR). The proposed system fully uses the excellent nonlinear estimation performance of SVR with the structural risk minimization principle. Closed-system stability and steady error are analyzed for the existence of modeling errors. The simulations show that the proposed control systems have the better control performance than that by neural networks in the cases of the training samples with small size and noises.

  16. Inverse Learning Control of Nonlinear Systems Using Support Vector Machines

    Institute of Scientific and Technical Information of China (English)

    HU Zhong-hui; LI Yuan-gui; CAI Yun-ze; XU Xiao-ming

    2005-01-01

    An inverse learning control scheme using the support vector machine (SVM) for regression was proposed. The inverse learning approach is originally researched in the neural networks. Compared with neural networks, SVMs overcome the problems of local minimum and curse of dimensionality. Additionally, the good generalization performance of SVMs increases the robustness of control system. The method of designing SVM inverselearning controller was presented. The proposed method is demonstrated on tracking problems and the performance is satisfactory.

  17. Predictors of Canadian legislators' support for tobacco control policies.

    Science.gov (United States)

    Cohen, Joanna E; de Guia, Nicole A; Ashley, Mary Jane; Ferrence, Roberta; Northrup, David A; Studlar, Donley T

    2002-09-01

    It is clear that regulatory strategies can be effective in reducing tobacco use. Because legislators ultimately determine whether many of these policies are enacted, they are a key focus for tobacco policy research. This study identifies political and personal predictors of Canadian legislators' support for tobacco control policies. Data are from a 1996-97 survey of federal, provincial and territorial legislators. Multivariate regression analysis was used to assess relationships between five groups of variables (political factors including political ideology, personal characteristics, tobacco experiences, tobacco knowledge, interest group saliency) and support for tobacco control based on an 11-item scale. Support for tobacco control varied by political party. Support was higher among legislators who thought government had a duty to promote healthy lifestyles, knew second-hand smoke could cause lung cancer, knew tobacco caused more deaths than alcohol, and said they wanted more contact with medical associations about tobacco issues. Support was lower among current smokers and those with tobacco industry jobs in their ridings. The findings indicate that political party membership cannot be ignored in enlisting legislator support for tobacco control. It also appears that legislators who oppose tobacco control measures may not be opposed to tobacco control per se, but are more generally opposed to a government role in health promotion. Thus, public health professionals and tobacco control advocates need to be more attentive to the way tobacco control issues are framed for particular legislators. Further, meetings with health groups about tobacco issues would be welcomed by many legislators; non-governmental organizations and other health advocates could work to increase tobacco knowledge among legislators.

  18. 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

  19. 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

  20. 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 t

  1. Dynamic Controls for Energy Efficiency and Demand Response:Framework Concepts and a New Construction Study Case in New York

    Energy Technology Data Exchange (ETDEWEB)

    Kiliccote, Sila; Piette, Mary Ann; Watson, David S.; Hughes, Glenn

    2006-06-20

    Many of today's advanced building control systems are designed to improve granularity of control for energy efficiency. Examples include direct digital controls for building heating, ventilation, and cooling systems (HVAC), and dimmable ballasts for continuous dimming for daylighting applications. This paper discusses recent research on the use of new and existing controls in commercial buildings for integrated energy efficiency and demand response (DR). The paper discusses the use of DR controls strategies in commercial buildings and provides specific details on DR control strategy design concepts for a new building in New York. We present preliminary results from EnergyPlus simulations of the DR strategies at the New York Times Headquarters building currently under construction. The DR strategies at the Times building involve unique state of the art systems with dimmable ballasts, movable shades on the glass facade, and underfloor air HVAC. The simulation efforts at this building are novel, with an innovative building owner considering DR and future DR program participation strategies during the design phase. This paper also discusses commissioning plans for the DR strategies. The trends in integration of various systems through the EMCS, master versus supervisory controls and dynamic operational modes concepts are presented and future research directions are outlined.

  2. 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

    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...... of the membrane-bound (F1F0) H+-ATP synthase were expressed in steadily growing Escherichia coli cells, which lowered the intracellular [ATP]/[ADP] ratio. This resulted in a strong stimulation of the specific glycolytic flux concomitant with a smaller decrease in the growth rate of the cells. By optimizing...... 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...

  3. Intelligent automated control of life support systems using proportional representations.

    Science.gov (United States)

    Wu, Annie S; Garibay, Ivan I

    2004-06-01

    Effective automatic control of Advanced Life Support Systems (ALSS) is a crucial component of space exploration. An ALSS is a coupled dynamical system which can be extremely sensitive and difficult to predict. As a result, such systems can be difficult to control using deliberative and deterministic methods. We investigate the performance of two machine learning algorithms, a genetic algorithm (GA) and a stochastic hill-climber (SH), on the problem of learning how to control an ALSS, and compare the impact of two different types of problem representations on the performance of both algorithms. We perform experiments on three ALSS optimization problems using five strategies with multiple variations of a proportional representation for a total of 120 experiments. Results indicate that although a proportional representation can effectively boost GA performance, it does not necessarily have the same effect on other algorithms such as SH. Results also support previous conclusions that multivector control strategies are an effective method for control of coupled dynamical systems.

  4. 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.

  5. 管制员需求量预测研究%Forecast Analysis on Demand of Air Traffic Controller

    Institute of Scientific and Technical Information of China (English)

    何昕; 高浩然; 陈亚青

    2011-01-01

    A series of statistical materials were collected,analyzed,and classified. Four different kinds of forecast models,namely the gray forecast model,comprehensive index method,multiple regression approach,and combined forecast model,were selected to forecast the time sequence of the demand quantity of air traffic controllers in the next 5 years in Chinese Civil Aviation. Corresponding accuracy analysis of the demand quantity was also carried out for the validity of prediction. The obtained predictive result is of great value for reference in various aspects, such as air traffic controller education and recruitment plans for the ATC institutions and authorities.%通过收集整理和分析一系列统计资料,选择灰色预测模型、灰色-马尔可夫预测模型、多元回归法和组合预测法等4种不同的人才需求量预测模型,预测出我国民航未来5年每年持照管制员需求量的时间序列,并进行了精确度分析.所得到的结果对我国民航各级管制单位制定人才引进计划,管制员培养院校制定招生计划均具有一定的参考价值.

  6. 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....

  7. 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

  8. 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 oft

  9. 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 predict

  10. Systems and methods for controlling energy use during a demand limiting period

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Controlled dispensing and mixing of pico- to nanoliter volumes using on-demand droplet-based microfluidics.

    Science.gov (United States)

    Sun, Xuefei; Tang, Keqi; Smith, Richard D; Kelly, Ryan T

    2013-07-01

    We present an integrated droplet-on-demand microfluidic platform for dispensing, mixing, incubating, extracting and analyzing by mass spectrometry pico- to nanoliter-sized droplets. All of the functional components are successfully integrated for the first time into a monolithic microdevice. Droplet generation is accomplished using computer-controlled pneumatic valves. Controlled actuation of valves for different aqueous streams enables accurate dosing and rapid mixing of reagents within droplets in either the droplet generation area or in a region of widening channel cross-section. Following incubation, which takes place as droplets travel in the oil stream, the droplet contents are extracted to an aqueous channel for subsequent ionization at an integrated nanoelectrospray emitter. Using the integrated platform, rapid enzymatic digestions of a model protein were carried out in droplets and detected on-line by nanoelectrospray ionization mass spectrometry.

  12. Public support toward tobacco control: consumer responsiveness and policy planning.

    Science.gov (United States)

    Raptou, Elena; Galanopoulos, Konstantinos; Katrakilidis, Constantinos; Mattas, Konstadinos

    2012-09-01

    To explore individual differences in support toward antismoking policies by investigating psychosocial, socioeconomic, and demographic characteristics; smoking restrictions; smoking status; and individually perceived cigarette price. The empirical analysis uses data from a random sample of 680 consumers and employs a bivariate semiordered probit model. Consumer responsiveness shows strong association with optimistic bias, perceived positive and negative consequences of smoking, health status, and family smoking patterns. Smoking status, gender, age, and occupation also affect antismoking policy support. Public support toward tobacco control reflects potential smoking acceptance and social norms, confirming policy effectiveness and current needs for demarketing tobacco use.

  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. 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...... are typically controlled by maintaining the static pressure at a fixed level at a selected point in the main duct. However, sustaining the static pressure at a fixed level at part load leads to throttling of all control components and thereby unnecessary energy consumption. Resetting the static pressure at part...... 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...

  15. 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.

  16. 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.

  17. PERFUSION SYSTEM CONTROLLER STRATEGIES DURING AN ECMO SUPPORT

    Directory of Open Access Journals (Sweden)

    M.Dhinakaran

    2014-12-01

    Full Text Available In this work modelling and control of Perfusion system is presented. The Perfusion system simultaneously controls the partial pressures during Extra Corporeal Membrane Oxygenation (ECMO support. The main Problem in ECMO system is exchange of Blood Gases in the Artificial Lung (Oxygenator.It is a highly Nonlinear Process comprising time-varying parameters, and varying time delays, it is currently being controlled manually by trained Perfusionist. The new control strategy implemented here has a feedback linearization routine with time-delay compensation for the Partial pressuresof Oxygen and Carbon dioxide. The controllers were tuned robustly and tested in simulations with a detailed artificial Lung (Oxygenator model in Cardiopulmonary bypass conditions. This Automatic control strategy is proposed to improve the patient’s safety by fast control reference tracking and good disturbance rejection under varying conditions.

  18. Subject-controlled, on-demand, dorsal genital nerve stimulation to treat urgency urinary incontinence, a pilot.

    Directory of Open Access Journals (Sweden)

    Hendrikje eVan Breda

    2016-02-01

    Full Text Available ObjectivesTo evaluate the effect of subject-controlled, on-demand, dorsal genital nerve stimulation on non-neurogenic urgency urinary incontinence in a domestic setting.Materials and MethodsNon-neurogenic patients >18 years with overactive bladder symptoms and urgency urinary incontinence were included. Exclusion criteria were mainly stress urinary incontinence. Patients underwent one week of subject-controlled, on-demand, dorsal genital nerve stimulation, delivered by a percutaneously placed electrode near the dorsal genital nerve connected to an external stimulator (pulse-rate 20 Hz, pulse-width 300 μs. Patients activated the stimulator when feeling the urge to void and stimulated for 30 s. The amplitude was set at the highest tolerable level. A bladder diary including a severity score of the urgency urinary incontinence episodes/void (scores: 0=none, 1=drops, 2=dashes, 3=soaks and a padtest was kept 3 days prior to, during, and 3 days after the test period. The subjective improvement was also scored.ResultsSeven patients (4 males / 3 females were enrolled, the mean age was 55 years (range 23-73. Six completed the test week. In the remaining patient the electrode migrated and was removed. 5/6 finalized the complete bladder diary, 1/6 recorded only the heavy incontinence episodes (score=3. 4/6 completed the padtest. In all patients who finalized the bladder diary the number of urgency urinary incontinence episodes decreased, in 3/5 with ≥60%. The heavy incontinence episodes (score=3 were resolved in 2/6 patients, and improved ≥ 80% in the other 4. The severity score of the urgency urinary incontinence episodes/void was improved with ≥60% in 3/5 patients. The mean subjective improvement was 73%. ConclusionThis feasibility study indicates that subject-controlled, on-demand dorsal genital nerve stimulation using a percutaneously placed electrode is possible over a longer time period, in a home setting, with a positive effect on non

  19. 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

  20. 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

    -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...... technical performance by effectively mitigating the overvoltages and improved economic performance by efficiently utilizing the PV power. For the given configuration and market structure, the presented method demonstrated 19.23% increment on PV power revenue and 25.73% decrement on EV charging cost....

  1. Support vector machine-based multi-model predictive control

    Institute of Scientific and Technical Information of China (English)

    Zhejing BA; Youxian SUN

    2008-01-01

    In this paper,a support vector machine-based multi-model predictive control is proposed,in which SVM classification combines well with SVM regression.At first,each working environment is modeled by SVM regression and the support vector machine network-based model predictive control(SVMN-MPC)algorithm corresponding to each environment is developed,and then a multi-class SVM model is established to recognize multiple operating conditions.As for control,the current environment is identified by the multi-class SVM model and then the corresponding SVMN.MPCcontroller is activated at each sampling instant.The proposed modeling,switching and controller design is demonstrated in simulation results.

  2. Age-related changes in postural control to the demands of a precision task.

    Science.gov (United States)

    Yeh, Ting-Ting; Cinelli, Michael E; Lyons, James L; Lee, Timothy D

    2015-12-01

    Optimal sensorimotor integration is needed to maintain the precision of a visuomotor postural task. Furthermore, cognitive resources have been suggested to be involved in maintaining balance, especially in older adults. This study investigated how older and younger adults differed in employing sensorimotor strategies in a dual-task situation. Older (age 65-84 years) and younger adults (age 19-30 years) performed a visually-based, postural tracking task in different body orientations (from 0° to 45°), which necessitated slightly different task goals. On some trials, participants performed a concurrent silent arithmetic task with the visuomotor tracking task. The results demonstrated that sensorimotor control declined with age. Older adults showed greater medial-lateral center of pressure variability compared to younger adults in the precision task. Younger adults displayed a trend to decrease anterior-posterior variability, but older adults exhibited an opposite trend when the body orientation changed from 0° to 45°. The addition of a dual-task situation decreased overall postural variability in both age groups. Age-related changes in postural control may degrade the flexible coordination of the sensory feedback and motor execution. This study suggested that medial-lateral stability may be more sensitive to this age-related decline and may be closely associated with postural instability and falls.

  3. 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.

  4. Commonality of flight control systems for support of European telecommunications missions

    Science.gov (United States)

    Debatin, Kurt

    1993-01-01

    This paper is concerned with the presentation of mission-independent software systems that provide a common software platform to ground data systems for mission operations. The objectives of such common software platforms are to reduce the cost of the development of mission-dedicated software systems and to increase the level of reliability of the ground data systems for mission operations. In accordance with this objective, the Multi-Satellite Support System (MSSS) was developed at the European Space Operations Center (ESOC). Between 1975 and 1992, the MSSS provided support to 16 European Space Agency (ESA) missions, among them very demanding science missions such as GEOS, EXOSAT, and Giotto. The successful support of these missions proved the validity of the MSSS concept with its extended mission-independent platform. This paper describes the MSSS concept and focuses on the wide use of MSSS as a flight control system for geosynchronous telecommunications satellites. Reference is made to more than 15 telecommunications missions that are operated from Western Europe using flight control systems with an underlying MSSS concept, demonstrating the benefits of a commonly used software platform. Finally, the paper outlines the design of the new generation of flight control systems, which is being developed at ESOC for this decade, following a period of more than 15 years of MSSS support.

  5. Alloy chemistry and microstructural control to meet the demands of the automotive Stirling engine

    Science.gov (United States)

    Stephens, Joseph R.

    1988-01-01

    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.

  6. 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.

  7. Temperature prediction control based on least squares support vector machines

    Institute of Scientific and Technical Information of China (English)

    Bin LIU; Hongye SU; Weihua HUANG; Jian CHU

    2004-01-01

    A prediction control algorithm is presented based on least squares support vector machines (LS-SVM) model for a class of complex systems with strong nonlinearity.The nonlinear off-line model of the controlled plant is built by LS-SVM with radial basis function (RBF) kernel.In the process of system running,the off-line model is linearized at each sampling instant,and the generalized prediction control (GPC) algorithm is employed to implement the prediction control for the controlled plant.The obtained algorithm is applied to a boiler temperature control system with complicated nonlinearity and large time delay.The results of the experiment verify the effectiveness and merit of the algorithm.

  8. 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…

  9. Controlling the Distribution of Supported Nanoparticles by Aqueous Synthesis

    NARCIS (Netherlands)

    Eggenhuisen, T.M.; Friedrich, H.; Nudelman, F.; Zečević, J.; Sommerdijk, N.A.J.M.; de Jongh, P.E.; de Jong, K.P.

    2013-01-01

    Synthesis of supported nanoparticles with controlled size and uniform distribution is a major challenge in nanoscience, in particular for applications in catalysis. Cryo-electron tomography revealed with nanometer resolution the 3D distribution of phases present during nanoparticle synthesis via imp

  10. Support Vector Machine-Based Nonlinear System Modeling and Control

    Institute of Scientific and Technical Information of China (English)

    张浩然; 韩正之; 冯瑞; 于志强

    2003-01-01

    This paper provides an introduction to a support vector machine, a new kernel-based technique introduced in statistical learning theory and structural risk minimization, then presents a modeling-control framework based on SVM.At last a numerical experiment is taken to demonstrate the proposed approach's correctness and effectiveness.

  11. 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.

  12. 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…

  13. 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...

  14. 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.

  15. Demand response-enabled model predictive HVAC load control in buildings using real-time electricity pricing

    Science.gov (United States)

    Avci, Mesut

    A practical cost and energy efficient model predictive control (MPC) strategy is proposed for HVAC load control under dynamic real-time electricity pricing. The MPC strategy is built based on a proposed model that jointly minimizes the total energy consumption and hence, cost of electricity for the user, and the deviation of the inside temperature from the consumer's preference. An algorithm that assigns temperature set-points (reference temperatures) to price ranges based on the consumer's discomfort tolerance index is developed. A practical parameter prediction model is also designed for mapping between the HVAC load and the inside temperature. The prediction model and the produced temperature set-points are integrated as inputs into the MPC controller, which is then used to generate signal actions for the AC unit. To investigate and demonstrate the effectiveness of the proposed approach, a simulation based experimental analysis is presented using real-life pricing data. An actual prototype for the proposed HVAC load control strategy is then built and a series of prototype experiments are conducted similar to the simulation studies. The experiments reveal that the MPC strategy can lead to significant reductions in overall energy consumption and cost savings for the consumer. Results suggest that by providing an efficient response strategy for the consumers, the proposed MPC strategy can enable the utility providers to adopt efficient demand management policies using real-time pricing. Finally, a cost-benefit analysis is performed to display the economic feasibility of implementing such a controller as part of a building energy management system, and the payback period is identified considering cost of prototype build and cost savings to help the adoption of this controller in the building HVAC control industry.

  16. 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.

  17. 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.

  18. 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.

  19. Is the demand-control model still a usefull tool to assess work-related psychosocial risk for ischemic heart disease? Results from 14 year follow up in the Copenhagen City Heart study

    DEFF Research Database (Denmark)

    Netterstrøm, Bo; Kristensen, Tage S; Jensen, Gorm;

    2010-01-01

    To test the usefulness of the Demand-Control Model as predictor for ischemic heart disease (IHD).......To test the usefulness of the Demand-Control Model as predictor for ischemic heart disease (IHD)....

  20. 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.

  1. 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

  2. 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...

  3. Mechanical demand and multijoint control during landing depend on orientation of the body segments relative to the reaction force.

    Science.gov (United States)

    McNitt-Gray, J L; Hester, D M; Mathiyakom, W; Munkasy, B A

    2001-11-01

    The purpose of this study was to determine how diverse momentum conditions and anatomical orientation at contact influences mechanical loading and multijoint control of the reaction force during landings. Male collegiate gymnasts (n=6) performed competition style landings (n=3) of drop jumps, front saltos, and back saltos from a platform (0.72 m) onto landing mats (0.12 m). Kinematics (200 fps), reaction forces (800 Hz) and muscle activation patterns (surface EMG, 1600 Hz) of seven lower extremity muscles were collected simultaneously. Between-task differences in segment orientation relative to the reaction force contributed to significant between-task differences in knee and hip net joint moments (NJM) during the impact phase. During the stabilization phase, ankle, knee, and hip NJMs acted to control joint flexion. Between-task differences in muscle activation patterns indicated that gymnasts scaled biarticular muscle activation to accommodate for between-task differences in NJM after contact. Activation of muscles on both sides of the joint suggests that impedance like control was used to stabilize the joints and satisfy the mechanical demand imposed on the lower extremity. Between-subject differences in the set of muscles used to control total body center of mass (TBCM) trajectory and achieve lower extremity NJMs suggests that control of multijoint movements involving impact needs to incorporate mechanical objectives at both the total body and local level. The functional consequences of such a control structure may prove to be an asset to gymnasts, particularly when required to perform a variety of landing tasks under a variety of environmental constraints.

  4. 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...... 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...

  5. 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.

  6. 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.

  7. 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.

  8. Demand forecasting

    OpenAIRE

    Gregor, Belčec

    2011-01-01

    Companies operate in an increasingly challenging environment that requires them to continuously improve all areas of the business process. Demand forecasting is one area in manufacturing companies where we can hope to gain great advantages. Improvements in forecasting can result in cost savings throughout the supply chain, improve the reliability of information and the quality of the service for our customers. In the company Danfoss Trata, d. o. o. we did not have a system for demand forecast...

  9. 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...... 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....... 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...

  10. Adaptive support vector regression for UAV flight control.

    Science.gov (United States)

    Shin, Jongho; Jin Kim, H; Kim, Youdan

    2011-01-01

    This paper explores an application of support vector regression for adaptive control of an unmanned aerial vehicle (UAV). Unlike neural networks, support vector regression (SVR) generates global solutions, because SVR basically solves quadratic programming (QP) problems. With this advantage, the input-output feedback-linearized inverse dynamic model and the compensation term for the inversion error are identified off-line, which we call I-SVR (inversion SVR) and C-SVR (compensation SVR), respectively. In order to compensate for the inversion error and the unexpected uncertainty, an online adaptation algorithm for the C-SVR is proposed. Then, the stability of the overall error dynamics is analyzed by the uniformly ultimately bounded property in the nonlinear system theory. In order to validate the effectiveness of the proposed adaptive controller, numerical simulations are performed on the UAV model.

  11. A Decision Support Tool for Transient Stability Preventive Control

    DEFF Research Database (Denmark)

    Pertl, Michael; Weckesser, Tilman; 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...... to assess the transient stability for potentially critical faults. Potential critical fault locations are identified by a critical bus screening through analysis of pre-disturbance steady-state conditions. The identified buses are subject to a fast critical contingency screening determining the actual....... The effectiveness of the proposed method is demonstrated on a standard nine-bus and the New England test system...

  12. 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

  13. Methodology and Assumptions of Contingency Shuttle Crew Support (CSCS) Calculations Using ISS Environmental Control and Life Support Systems

    Science.gov (United States)

    Prokhorov, Kimberlee; Shkedi, Brienne

    2006-01-01

    The current International Space Station (ISS) Environmental Control and Life Support (ECLS) system is designed to support an ISS crew size of three people. The capability to expand that system to support nine crew members during a Contingency Shuttle Crew Support (CSCS) scenario has been evaluated. This paper describes how the ISS ECLS systems may be operated for supporting CSCS, and the durations expected for the oxygen supply and carbon dioxide control subsystems.

  14. Regulatory mode preferences for autonomy supporting versus controlling instructional styles.

    Science.gov (United States)

    Pierro, Antonio; Presaghi, Fabio; Higgins, Tory E; Kruglanski, Arie W

    2009-12-01

    Three studies carried out in educational settings examined determinants of teacher's instructional styles and students' degree of satisfaction with the learning climates created by such styles. Based upon regulatory mode theory, Studies 1 and 2 tested the hypotheses that teachers' locomotion orientation will be positively related, and their assessment orientation will be negatively related, to autonomy supportive (vs. controlling) instructional styles. Study 3 tested the hypothesis that students' regulatory mode will exhibit a fit effect with the prevalent learning climate in their school. Participants for Study 1 were 378 teachers (278 females); for Study 2 were 96 teachers (65 females); and for Study 3 were 190 students (all males). Participants completed questionnaires that included measures of teaching styles (Studies 1 and 2), perceived learning climate and satisfaction (Study 3), and regulatory mode orientations (Studies 1 and 3). In Study 2 regulatory mode orientations were experimentally induced. Results confirmed that teachers' autonomy supportive versus controlling styles were positively related to their locomotion orientations and negatively related to their assessment orientation, and that students with a stronger locomotion (vs. assessment) orientation reported a higher level of satisfaction when the learning climate was perceived as autonomy supportive (vs. controlling). The present studies show that teachers' preference for adopting an instructional style is influenced by their regulatory mode orientations, and that the effects of a learning climate on students' satisfaction are contingent on a fit between type of learning climate and students' regulatory mode orientations.

  15. Adsorption processes in spacecraft environmental control and life support systems.

    Science.gov (United States)

    DallBauman, L A; Finn, J E

    1999-01-01

    The environmental control and life support system on a spacecraft maintains a safe and comfortable environment in which the crew can live and work by supplying oxygen and water and by removing carbon dioxide, water vapor, and trace contaminants from cabin air. Although open-loop systems have been used successfully in the past for short-duration missions, the economics of current and future long-duration missions in space will make nearly complete recycling of air and water imperative. A variety of operations will be necessary to achieve the goal of nearly complete recycling. These include separation and reduction of carbon dioxide, removal of trace gas-phase contaminants, recovery and purification of humidity condensate, purification and polishing of wastewater streams, and others. Several of these can be performed totally or in part by adsorption processes. These processes are good candidates to perform separations and purifications in space due to their gravity independence, high reliability, relative high energy efficiency, design flexibility, technological maturity, and regenerative nature. For these reasons, adsorption has historically played a key role in life support on U.S. and Russian piloted spacecraft. Among the life support applications that can be achieved through use of adsorption technology are removal of trace contaminants and carbon dioxide from cabin air and recovery of potable water from waste streams. In each of these cases adsorption technology has been selected for use onboard the International Space Station. The requirements, science, and hardware for these applications are discussed. Human space exploration may eventually lead to construction of planetary habitats. These habitats may provide additional opportunities for use of adsorption processes, such as control of greenhouse gas composition, and may have different resources available to them, such as gases present in the planetary atmosphere. Separation and purification processes based on

  16. Control Scheme for Distributed Generator Providing Network Voltage Support

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The distributed generator over the last 30 years has posed several challenges when they are connected to a distributed network. The most immediate problem is to change the voltage at the connection point depending on the power supplied to the network and may cause it to exceed statutory limits. This paper describes a new control scheme for a distributed generator for supporting the voltage control in the network, thus ensuring the distributed generator to contribute to network voltage management. The scheme performance is demonstrated by a model for a distributed generator connected to a distribution network. The result shows that using the new control scheme, the distribution network voltage constraints are maintained while maximizing the active power delivered by distributed generators.

  17. Some Effects of Noncontingent Positive Reinforcement on Multiply Controlled Problem Behavior and Compliance in a Demand Context

    Science.gov (United States)

    Ingvarsson, Einar T.; Kahng, SungWoo; Hausman, Nicole L.

    2008-01-01

    Functional analysis suggested that the problem behavior of an 8-year-old girl with autism was maintained by escape from demands and access to edible items. Noncontingent delivery of an edible item was sufficient to increase compliance and reduce the rate of problem behavior without the use of escape extinction in a demand context. Leaner and…

  18. Cardiopulmonary resuscitation support application on a smartphone - randomized controlled trial.

    Science.gov (United States)

    Sakai, Tomohiko; Kitamura, Tetsuhisa; Nishiyama, Chika; Murakami, Yukiko; Ando, Masahiko; Kawamura, Takashi; Tasaki, Osamu; Kuwagata, Yasuyuki; Shimazu, Takeshi; Iwami, Taku

    2015-01-01

    This simulation trial aimed to compare the quality of cardiopulmonary resuscitation (CPR) with and without the newly-developed CPR support application on smartphones. In this trial, participants were randomly assigned to either the CPR support application group or the control group, stratified by sex and previous CPR training. Participants' CPR skills were evaluated by a 2-min case-based scenario test using the Leardal Resusci Anne PC Skill reporting Manikin System(®). The outcome measures were the proportion of chest compressions performed in each group and the number of total chest compressions and appropriate chest compressions performed during the 2-min test period. A total of 84 participants were enrolled and completed the protocol. All participants in the CPR support application group performed chest compressions, compared with only 31 (75.6%) in the control group (Psmartphones contributed to increasing the implementation rate and the number of total chest compressions performed and may assist in improving the survival rate for out-of-hospital cardiac arrests (UMIN000004740).

  19. 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

  20. Geometric control of rippling in supported polymer nanolines.

    Science.gov (United States)

    Tirumala, Vijay R; Stafford, Christopher M; Ocola, Leonidas E; Douglas, Jack F; Mahadevan, L

    2012-03-14

    We study the swelling behavior of finlike polymer line gratings supported on a rigid substrate and show that the edge-supported polymer laminae undergo a rippling instability with a well-defined ripple wavelength λ transverse to the plane of the solid supporting substrate and a ripple amplitude that monotonically decreases from its maximum at the free-edge. These ripple patterns develop due to inhomogeneous compressive strains that arise from the geometric constraints that progressively suppress swelling near the supporting substrate where the laminae are clamped. By experimentally examining the influence of swelling strain and pattern geometry on the observed rippling instability, we find that the ripple wavelength λ scales with line width w for sufficiently long gratings, which is consistent with a simple theory. These trends were validated for polymer nanoline test patterns having w between (50 to 250) nm and a height-to-width aspect-ratio in the range 0.5 to 5. Our results suggest that line geometry, rather than material properties, governs the onset of rippling and suggest simple rules for their control.

  1. Computer simulation to support policy making in the control of pseudorabies.

    NARCIS (Netherlands)

    Buijtels, J.A.A.M.; Huirne, R.B.M.; Dijkhuizen, A.A.; Jong, de M.C.M.; Nes, van A.

    1997-01-01

    A further integration of international markets makes a coordinated policy against contagious animal infections increasingly important. In the future, stricter demands are to be expected concerning the control and eradication of such infections. To anticipate these demands, a computer simulation mode

  2. Factorial invariance, scale reliability, and construct validity of the job control and job demands scales for immigrant workers: the multi-ethnic study of atherosclerosis.

    Science.gov (United States)

    Fujishiro, Kaori; Landsbergis, Paul A; Diez-Roux, Ana V; Stukovsky, Karen Hinckley; Shrager, Sandi; Baron, Sherry

    2011-06-01

    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 = 3,114, mean age = 58.1). Across all groups, the job control scale had acceptable Cronbach's alpha (0.78-0.83) and equivalent factor loadings (ΔCFI 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.

  3. 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.

  4. Multi-Item Multiperiodic Inventory Control Problem with Variable Demand and Discounts: A Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Seyed Mohsen Mousavi

    2014-01-01

    Full Text Available A multi-item multiperiod inventory control model is developed for known-deterministic variable demands under limited available budget. Assuming the order quantity is more than the shortage quantity in each period, the shortage in combination of backorder and lost sale is considered. The orders are placed in batch sizes and the decision variables are assumed integer. Moreover, all unit discounts for a number of products and incremental quantity discount for some other items are considered. While the objectives are to minimize both the total inventory cost and the required storage space, the model is formulated into a fuzzy multicriteria decision making (FMCDM framework and is shown to be a mixed integer nonlinear programming type. In order to solve the model, a multiobjective particle swarm optimization (MOPSO approach is applied. A set of compromise solution including optimum and near optimum ones via MOPSO has been derived for some numerical illustration, where the results are compared with those obtained using a weighting approach. To assess the efficiency of the proposed MOPSO, the model is solved using multi-objective genetic algorithm (MOGA as well. A large number of numerical examples are generated at the end, where graphical and statistical approaches show more efficiency of MOPSO compared with MOGA.

  5. 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.

  6. High metabolic demand in neural tissues: Information and control theory perspectives on the synergism between rate and stability.

    Science.gov (United States)

    Wallace, Rodrick

    2016-11-21

    Evolutionary process has been selected for inherently unstable systems in higher animals that can react swiftly to changing patterns of threat or opportunity, for example blood pressure, the immune response, and gene expression. However, these require continual strict regulation: uncontrolled blood pressure is fatal, immune cells can attack 'self' tissues, and improper gene expression triggers developmental disorders. Consciousness in particular demands high rates of metabolic free energy to both operate and regulate the fundamental biological machinery: both the 'stream of consciousness' and the 'riverbanks' that confine it to useful realms are constructed and reconstructed moment-by-moment in response to highly dynamic internal and environmental circumstances. We develop powerful necessary conditions models for such phenomena based on the Data Rate Theorem linking control and information theories in the context of inherent instability. The synergism between conscious action and its regulation underlies the ten-fold higher rate of metabolic energy consumption in human neural tissues and implies a close, culturally modulated relation between sleep disorders and certain psychopathologies.

  7. Multi-item multiperiodic inventory control problem with variable demand and discounts: a particle swarm optimization algorithm.

    Science.gov (United States)

    Mousavi, Seyed Mohsen; Niaki, S T A; Bahreininejad, Ardeshir; Musa, Siti Nurmaya

    2014-01-01

    A multi-item multiperiod inventory control model is developed for known-deterministic variable demands under limited available budget. Assuming the order quantity is more than the shortage quantity in each period, the shortage in combination of backorder and lost sale is considered. The orders are placed in batch sizes and the decision variables are assumed integer. Moreover, all unit discounts for a number of products and incremental quantity discount for some other items are considered. While the objectives are to minimize both the total inventory cost and the required storage space, the model is formulated into a fuzzy multicriteria decision making (FMCDM) framework and is shown to be a mixed integer nonlinear programming type. In order to solve the model, a multiobjective particle swarm optimization (MOPSO) approach is applied. A set of compromise solution including optimum and near optimum ones via MOPSO has been derived for some numerical illustration, where the results are compared with those obtained using a weighting approach. To assess the efficiency of the proposed MOPSO, the model is solved using multi-objective genetic algorithm (MOGA) as well. A large number of numerical examples are generated at the end, where graphical and statistical approaches show more efficiency of MOPSO compared with MOGA.

  8. User-Preference-Driven Model Predictive Control of Residential Building Loads and Battery Storage for Demand Response

    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); Isley, Steven C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Christensen, Dane T [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-07-03

    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.

  9. Demanding Satisfaction

    Science.gov (United States)

    Oguntoyinbo, Lekan

    2010-01-01

    It was the kind of crisis most universities dread. In November 2006, a group of minority student leaders at Indiana University-Purdue University Indianapolis (IUPUI) threatened to sue the university if administrators did not heed demands that included providing more funding for multicultural student groups. This article discusses how this threat…

  10. Comparison of alternative versions of the job demand-control scales in 17 European cohort studies: the IPD-Work consortium

    Directory of Open Access Journals (Sweden)

    Fransson Eleonor I

    2012-01-01

    Full Text Available Abstract Background Job strain (i.e., high job demands combined with low job control is a frequently used indicator of harmful work stress, but studies have often used partial versions of the complete multi-item job demands and control scales. Understanding whether the different instruments assess the same underlying concepts has crucial implications for the interpretation of findings across studies, harmonisation of multi-cohort data for pooled analyses, and design of future studies. As part of the 'IPD-Work' (Individual-participant-data meta-analysis in working populations consortium, we compared different versions of the demands and control scales available in 17 European cohort studies. Methods Six of the 17 studies had information on the complete scales and 11 on partial scales. Here, we analyse individual level data from 70 751 participants of the studies which had complete scales (5 demand items, 6 job control items. Results We found high Pearson correlation coefficients between complete scales of job demands and control relative to scales with at least three items (r > 0.90 and for partial scales with two items only (r = 0.76-0.88. In comparison with scores from the complete scales, the agreement between job strain definitions was very good when only one item was missing in either the demands or the control scale (kappa > 0.80; good for job strain assessed with three demand items and all six control items (kappa > 0.68 and moderate to good when items were missing from both scales (kappa = 0.54-0.76. The sensitivity was > 0.80 when only one item was missing from either scale, decreasing when several items were missing in one or both job strain subscales. Conclusions Partial job demand and job control scales with at least half of the items of the complete scales, and job strain indices based on one complete and one partial scale, seemed to assess the same underlying concepts as the complete survey instruments.

  11. 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.

  12. Hardware support for software controlled fast reconfiguration of performance counters

    Science.gov (United States)

    Salapura, Valentina; Wisniewski, Robert W

    2013-09-24

    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.

  13. 考虑不同需求偏好的可控负荷需求响应菜单定价研究%Study on the menu-pricing of controllable load demand response considering different demand and preference

    Institute of Scientific and Technical Information of China (English)

    张俊; 李文东; 杨洪朝

    2015-01-01

    随着智能电网技术的不断发展,需求侧大量的可控负荷资源主动参与电网调度成为可能,如何设计有效的价格机制来激励用户主动的需求响应成为目前值得研究的热点问题。然而,传统固定单一价格的定价模式已经很难满足不同用户深层次的差异化需求。提出一种可控负荷需求响应菜单定价方法,该方法以可控负荷用户的需求为导向,考虑不同用户的需求偏好特性并划分用户类型;以需求响应电价和负荷削减量为菜单选项,构建以系统供电总成本最小为目标函数的可控负荷需求响应菜单定价模型。算例分析表明,该定价方法能够对不同偏好的用户进行有效区隔,增加了用户对电价的自主选择性,提高了用户参与的积极性,实现了电力资源的优化配置。%With the development of smart grid technologies,it become possible for a large number of controllable load resources on the demand-side to participate in power grid dispatching actively. How to design an effective price mechanism to motivate users to take the initiative to demand re-sponse becomes a problem,which is worthy of study at present.However,the traditional single price model has been difficult to meet different users demands of deep-seated differences.A menu-pricing of the controllable load demand response considering different demand and preference was proposed in this paper.Taking the demand of controllable load users as a guidance,the method considered the needs of different users preference and then divided the user classification.Taking the cost of power supply as minimum objective function,a menu pricing decision model of the controllable load demand response was set up.A case study results showed that the pricing meth-od could segment the different preferences of users effectively,and increase the independence se-lectivity of electricity prices.It can still improve the enthusiasm of users

  14. Shuttle Orbiter Environmental Control and Life Support System - Flight experience

    Science.gov (United States)

    Winkler, H. E.

    1992-01-01

    This paper describes the overall design of the Shuttle Orbiter Environmental Control and Life Support System (ECLSS). The Orbiter ECLSS consists of six major subsystems which accomplish the functions of providing a habitable pressurized cabin atmosphere and removing gaseous contaminants, controlling the temperature of the cabin and vehicle components within acceptable ranges, providing fire detection and suppression capability, maintaining a supply of potable water, collecting and removing metabolic waste materials, and providing utilities and access for extravehicular activity. The operational experience is summarized for the 45 space flights accomplished to date during which the Orbiter ECLSS has been demonstrated to perform reliably, and has proved to have the flexibility to meet a variety of mission needs. Significant flight problems are described, along with the design or procedure changes which were implemented to resolve the problems.

  15. 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...

  16. 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.

  17. A formal model for access control with supporting spatial context

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong; HE YePing; SHI ZhiGuo

    2007-01-01

    There is an emerging recognition of the importance of utilizing contextual information in authorization decisions. Controlling access to resources in the field of wireless and mobile networking require the definition of a formal model for access control with supporting spatial context. However, traditional RBAC model does not specify these spatial requirements. In this paper, we extend the existing RBAC model and propose the SC-RBAC model that utilizes spatial and location-based information in security policy definitions. The concept of spatial role is presented,and the role is assigned a logical location domain to specify the spatial boundary.Roles are activated based on the current physical position of the user which obtained from a specific mobile terminal. We then extend SC-RBAC to deal with hierarchies, modeling permission, user and activation inheritance, and prove that the hierarchical spatial roles are capable of constructing a lattice which is a means for articulate multi-level security policy and more suitable to control the information flow security for safety-critical location-aware information systems. Next, constrained SC-RBAC allows express various spatial separations of duty constraints,location-based cardinality and temporal constraints for specify fine-grained spatial semantics that are typical in location-aware systems. Finally, we introduce 9 invariants for the constrained SC-RBAC and its basic security theorem is proven. The constrained SC-RBAC provides the foundation for applications in need of the constrained spatial context aware access control.

  18. Management of quality-assurance controls: decision support systems

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, M.P.; Strand, R.H.

    1981-01-01

    Environmental research involved in the assessment of new coal conversion technologies must evaluate many biological, physical and chemical variables to determine environmental acceptability. Inherent in these studies is the use of quality assurance controls to evaluate data base entries, analytical procedures, and program productivity. However, quality assurance controls implemented at the project level are seldom known in detail and/or evaluated when making resource management decisions at the program level. This paper presents a computer based decision support system that assists in management level integration of complex environmental research. The DSS is modeled after an open-ended construct applied to data management systems developed for environmental research programs, i.e., minimal planning effort and a flexible system that can accommodate changing research emphasis. We have found that by interfacing the DSS with the research data base management system, more appropriate statistical measures can be formulated to provide management support for evaluating program progress, status reports of current findings, and comparisons of findings with standards.

  19. 需求响应中的直接负荷控制策略%Tactics of Direct Load Control in Demand Response

    Institute of Scientific and Technical Information of China (English)

    冯庆东; 何战勇

    2012-01-01

    This paper introduces the principles of direct load management in demand response, the research background of relevant control strategy and the current research has been made at home and abroad, describes the meaning of demand response, technology infrastructures and the driving force of demand response. And also gives direct load control strategy detailed analysis and description.%文章介绍了需求响应中的直接负荷管理的原理、相关控制策略,以及当前国内外已取得的研究成果,描述了需求响应的内涵、技术基础及实施需求响应的驱动力.并且对直接负荷控制策略进行了详细分析与介绍.

  20. Some effects of noncontingent positive reinforcement on multiply controlled problem behavior and compliance in a demand context.

    Science.gov (United States)

    Ingvarsson, Einar T; Kahng, Sungwoo; Hausman, Nicole L

    2008-01-01

    Functional analysis suggested that the problem behavior of an 8-year-old girl with autism was maintained by escape from demands and access to edible items. Noncontingent delivery of an edible item was sufficient to increase compliance and reduce the rate of problem behavior without the use of escape extinction in a demand context. Leaner and richer schedules of noncontingent reinforcement were equally effective, and there were minimal differences between noncontingent reinforcement and differential reinforcement of compliance.

  1. Automated Demand Response Opportunities in Wastewater Treatment Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Lisa; Song, Katherine; Lekov, Alex; McKane, Aimee

    2008-11-19

    Wastewater treatment is an energy intensive process which, together with water treatment, comprises about three percent of U.S. annual energy use. Yet, since wastewater treatment facilities are often peripheral to major electricity-using industries, they are frequently an overlooked area for automated demand response opportunities. Demand response is a set of actions taken to reduce electric loads when contingencies, such as emergencies or congestion, occur that threaten supply-demand balance, and/or market conditions occur that raise electric supply costs. Demand response programs are designed to improve the reliability of the electric grid and to lower the use of electricity during peak times to reduce the total system costs. Open automated demand response is a set of continuous, open communication signals and systems provided over the Internet to allow facilities to automate their demand response activities without the need for manual actions. Automated demand response strategies can be implemented as an enhanced use of upgraded equipment and facility control strategies installed as energy efficiency measures. Conversely, installation of controls to support automated demand response may result in improved energy efficiency through real-time access to operational data. This paper argues that the implementation of energy efficiency opportunities in wastewater treatment facilities creates a base for achieving successful demand reductions. This paper characterizes energy use and the state of demand response readiness in wastewater treatment facilities and outlines automated demand response opportunities.

  2. 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

  3. The Controlling Model as Management Support in Decision- Making

    Directory of Open Access Journals (Sweden)

    Berislav Bolfek

    2010-07-01

    Full Text Available business system to operate successfully and make profit, which represents the success criterion for each business system on the market. For managing the business result, the management of business systems needs different types of information on which numerous managerial decisions are based. That is why it is necessary to develop and set a Business System Controlling Model which would have the capability to transform available data into the information necessary for managerial decision-making. The above-mentioned model is prepared in such a way that the whole process of the transformation of the data into required information is carried out in two interconnected steps which have to be made in every single case and situation. However, there are a certain number of different activities within each step which do not have to be performed in every case. The forecast presented in the form of the Profit Forecast Procedure and the Liquidity Forecast Procedure represents the essence of the Business System Controlling Model. The Business System Controlling Model developed and set out in this paper should enable the business system management to evaluate future business activities, in addition to monitoring the past and present business activities. It is precisely the evaluation of the future business activities that, in today’s conditions of greater market globalization and internationalization, should help the business system management to control the business result in a better and easier way. In this way, the Business System Controlling Model represents a new tool in the sense of management support in making various business decisions.

  4. The Effects of Job Demands and Low Job Control on Work-Family Conflict: The Role of Fairness in Decision Making and Management

    Science.gov (United States)

    Heponiemi, Tarja; Elovainio, Marko; Pekkarinen, Laura; Sinervo, Timo; Kouvonen, Anne

    2008-01-01

    The present study examined whether perceptions of organizational fairness (the procedural and interactional components) were able to diminish the negative effects of high job demands and low job control on the balance between work and family. The study participants were 713 women working in long-term care for elderly people in Finland. The results…

  5. 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

  6. Environmental Control and Life Support System, Oxygen Generation System

    Science.gov (United States)

    2000-01-01

    The Environmental Control and Life Support System (ECLSS) Group of the Flight Projects Directorate at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, is responsible for designing and building the life support systems that will provide the crew of the International Space Station (ISS) a comfortable environment in which to live and work. This is a close-up view of ECLSS Oxygen Generation System (OGS) rack. The ECLSS Group at the MSFC oversees the development of the OGS, which produces oxygen for breathing air for the crew and laboratory animals, as well as for replacing oxygen lost due to experiment use, airlock depressurization, module leakage, and carbon dioxide venting. The OGS consists primarily of the Oxygen Generator Assembly (OGA), provided by the prime contractor, the Hamilton Sundstrand Space Systems, International (HSSSI) in Windsor Locks, Cornecticut and a Power Supply Module (PSM), supplied by the MSFC. The OGA is comprised of a cell stack that electrolyzes (breaks apart the hydrogen and oxygen molecules) some of the clean water provided by the Water Recovery System and the separators that remove the gases from water after electrolysis. The PSM provides the high power to the OGA needed to electrolyze the water.

  7. 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

    Full Text Available 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 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.

  8. 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.

  9. 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...... the high rate of exit seen in the first years of exporting. Finally, when faced with multiple countries in which to export, some firms will choose to sequentially export in order to slowly learn more about its chances for success in untested markets....

  10. 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.

  11. Decision Making and the Avoidance of Cognitive Demand

    Science.gov (United States)

    Kool, Wouter; McGuire, Joseph T.; Rosen, Zev B.; Botvinick, Matthew M.

    2010-01-01

    Behavioral and economic theories have long maintained that actions are chosen so as to minimize demands for exertion or work, a principle sometimes referred to as the “law of less work.” The data supporting this idea pertain almost entirely to demands for physical effort. However, the same minimization principle has often been assumed also to apply to cognitive demand. We set out to evaluate the validity of this assumption. In six behavioral experiments, participants chose freely between courses of action associated with different levels of demand for controlled information processing. Together, the results of these experiments revealed a bias in favor of the less demanding course of action. The bias was obtained across a range of choice settings and demand manipulations, and was not wholly attributable to strategic avoidance of errors, minimization of time on task, or maximization of the rate of goal achievement. Remarkably, the effect also did not depend on awareness of the demand manipulation. Consistent with a motivational account, avoidance of demand displayed sensitivity to task incentives and co-varied with individual differences in the efficacy of executive control. The findings reported, together with convergent neuroscientific evidence, lend support to the idea that anticipated cognitive demand plays a significant role in behavioral decision-making. PMID:20853993

  12. Travel Demand Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, Frank [ORNL; Garrow, Dr. Laurie [Georgia Institute of Technology

    2011-01-01

    This chapter describes the principal types of both passenger and freight demand models in use today, providing a brief history of model development supported by references to a number of popular texts on the subject, and directing the reader to papers covering some of the more recent technical developments in the area. Over the past half century a variety of methods have been used to estimate and forecast travel demands, drawing concepts from economic/utility maximization theory, transportation system optimization and spatial interaction theory, using and often combining solution techniques as varied as Box-Jenkins methods, non-linear multivariate regression, non-linear mathematical programming, and agent-based microsimulation.

  13. Control of voluntary feed intake in fish: a role for dietary oxygen demand in Nile tilapia (Oreochromis niloticus) fed diets with different macronutrient profiles.

    Science.gov (United States)

    Saravanan, S; Geurden, I; Figueiredo-Silva, A C; Kaushik, S J; Haidar, M N; Verreth, J A J; Schrama, J W

    2012-10-28

    It has been hypothesised that, at non-limiting water oxygen conditions, voluntary feed intake (FI) in fish is limited by the maximal physiological capacity of oxygen use (i.e. an 'oxystatic control of FI in fish'). This implies that fish will adjust FI when fed diets differing in oxygen demand, resulting in identical oxygen consumption. Therefore, FI, digestible energy (DE) intake, energy balance and oxygen consumption were monitored at non-limiting water oxygen conditions in Nile tilapia fed diets with contrasting macronutrient composition. Diets were formulated in a 2 × 2 factorial design in order to create contrasts in oxygen demand: two ratios of digestible protein (DP):DE ('high' v. 'low'); and a contrast in the type of non-protein energy source ('starch' v. 'fat'). Triplicate groups of tilapia were fed each diet twice daily to satiation for 48 d. FI (g DM/kg(0·8) per d) was significantly lower (9·5%) in tilapia fed the starch diets relative to the fat diets. The DP:DE ratio affected DE intakes (P demand of these diets. Indeed, DE intakes of fish showed an inverse linear relationship with dietary oxygen demand (DOD; R 2 0·81, P theory), oxygen consumption of fish was identical among three out of the four diets. Altogether, these results demonstrate the involvement of metabolic oxygen use and DOD in the control of FI in tilapia.

  14. What do Demand-Control and Effort-Reward work stress questionnaires really measure? A discriminant content validity study of relevance and representativeness of measures.

    Science.gov (United States)

    Bell, Cheryl; Johnston, Derek; Allan, Julia; Pollard, Beth; Johnston, Marie

    2017-05-01

    The Demand-Control (DC) and Effort-Reward Imbalance (ERI) models predict health in a work context. Self-report measures of the four key constructs (demand, control, effort, and reward) have been developed and it is important that these measures have good content validity uncontaminated by content from other constructs. We assessed relevance (whether items reflect the constructs) and representativeness (whether all aspects of the construct are assessed, and all items contribute to that assessment) across the instruments and items. Two studies examined fourteen demand/control items from the Job Content Questionnaire and seventeen effort/reward items from the Effort-Reward Imbalance measure using discriminant content validation and a third study developed new methods to assess instrument representativeness. Both methods use judges' ratings and construct definitions to get transparent quantitative estimates of construct validity. Study 1 used dictionary definitions while studies 2 and 3 used published phrases to define constructs. Overall, 3/5 demand items, 4/9 control items, 1/6 effort items, and 7/11 reward items were uniquely classified to the appropriate theoretical construct and were therefore 'pure' items with discriminant content validity (DCV). All pure items measured a defining phrase. However, both the DC and ERI assessment instruments failed to assess all defining aspects. Finding good discriminant content validity for demand and reward measures means these measures are usable and our quantitative results can guide item selection. By contrast, effort and control measures had limitations (in relevance and representativeness) presenting a challenge to the implementation of the theories. Statement of contribution What is already known on this subject? While the reliability and construct validity of Demand-Control and Effort-Reward-Imbalance (DC and ERI) work stress measures are routinely reported, there has not been adequate investigation of their content

  15. Computer Supported Control Education from a Linköping Perspective

    OpenAIRE

    Gunnarsson, Svante; Millnert, Mille

    1997-01-01

    The development of computer supported control education at Linköping University is presented. A review of the different phases of development of computer support is given. The experiences from the introduction of computer supported exams are discussed.

  16. Controlled environment life support system: Growth studies with potatoes

    Science.gov (United States)

    Tibbitts, T. W.; Wheeler, R. M.

    1986-01-01

    Results of experiments conducted to maximize the productivity of potatoes grown under controlled environmental conditions are discussed. A variety of parameters is examined which affect potato growth, specifically, photoperiod, light intensity, temperature, nitrogen nutrition, carbon dioxide concentration and culture techniques. These experiments were conducted using five different cultivars, Russet Burbank, Norchip, Superior, Kennebec and Norland. To achieve high productivity, three specific objectives were explored: (1) to develop effective cultural procedures, (2) to determine the most effective photoperiod and (3) to develop a mist culture system. It is felt that the productivity obtained in this study is below the maximum that can be obtained. High irradiance levels coupled with tuber-promoting conditions such as cooler temperatures, increased CO2 levels and lowered nitrogen concentrations should allow increases in tuber production. Tuberization appears to be accelerated by short daylengths although final yields are not increased. Mist culture techniques have not yet produced fully developed tubers. The use of supporting media and alteration of the nitrogen content of the mist solution are being explored as a way to allow tubers to develop to maturity.

  17. 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.

  18. Frequency Support of PMSG-WTG Based on Improved Inertial Control

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z.; Wang, X.; Gao, W.; Kang, M.; Hwang, M.; Kang, Y.; Gevorgian, Vahan; Muljadi, Eduard

    2016-11-14

    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.

  19. 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.

  20. 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.

  1. 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

    2015-01-01

    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. PMID:25723145

  2. Notice of Retraction: Enhanced Link based Congestion Control (ELCC in Peer-to-Peer (P2P based Video on Demand (VoD System

    Directory of Open Access Journals (Sweden)

    Arockia Xavier Annie. Rayan

    2012-10-01

    Full Text Available The following article has been retracted by the Editorial Board and the Publisher of Journal of Networks: “Enhanced Link based Congestion Control (ELCC in Peer-to-Peer (P2P based Video on Demand (VoD System” by Arockia Xavier Annie Rayan and Yogesh Palanichamy Journal of Networks Volume 7, Number 10, October 2012, Pages: 1515-1522 doi:10.4304/jnw.7.10.1515-1522 The retraction is based on the determination of redundant publication. The same article has been published as follows: “Enhanced Link based Congestion Control (ELCC in Peer-to-Peer (P2P based Video on Demand (VoD System” by Arockia Xavier Annie R., Vanitha Sheba M. and Yogesh P. International Journal of Computer Applications 36(1:18-26, December 2011. Published by Foundation of Computer Science, New York, USA URL: http://www.ijcaonline.org/archives/volume36/number1/4455-6238

  3. 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 ...... 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.......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...

  4. 智能变电站和调控主站的模型按需共享技术%Model Sharing Technologies on Demand Between Smart Substations and Control Centers

    Institute of Scientific and Technical Information of China (English)

    丁宏恩; 赵家庆; 苏大威; 杨志宏; 宋鑫; 肖翔

    2012-01-01

    基于IEC61850与IEC61970提出电网模型由主站集中建模变为分布式按需裁剪引用变电站模型的策略,解决了智能变电站与各级调控主站之间以及各级调控主站之间的电网模型、变电站接线图、量测信息的按需共享问题。成果已成功应用于苏州500kV常熟智能变电站、智能电网调度技术支持系统等试点工程。%Based on IEC 61850 and IEC 61970, a power grid modeling strategy is presented to make transition from concentrated modeling for main control center to reference substation model on demand by different control centers. Then it solves on- demand sharing of grid model, substation's wiring diagram and measuring information between smart substations and control centers at all levels, and among control centers at all levels. The research result has been applied to Suzhou' s 500 kV Changshu smart substation and smart grid dispatching technology support system pilot projects.

  5. 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…

  6. 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…

  7. 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....

  8. Towards Greater Learner Control: Web Supported Project-Based Learning

    Science.gov (United States)

    Guthrie, Cameron

    2010-01-01

    Project-based learning has been suggested as an appropriate pedagogy to prepare students in information systems for the realities of the business world. Web-based resources have been used to support such pedagogy with mixed results. The paper argues that the design of web-based learning support to cater to different learning styles may give…

  9. From Victim to Taking Control: Support Group for Bullied Schoolchildren

    Science.gov (United States)

    Kvarme, Lisbeth Gravdal; Aabø, Liv Sandnes; Saeteren, Berit

    2016-01-01

    School bullying is a serious problem affecting the victims in their daily lives at school. The aim of this study was to investigate whether support groups were able to help the victims of bullying to overcome their victim status and to explore what it means to be a member of a support group. An exploratory qualitative design, with individual and…

  10. Towards Greater Learner Control: Web Supported Project-Based Learning

    Science.gov (United States)

    Guthrie, Cameron

    2010-01-01

    Project-based learning has been suggested as an appropriate pedagogy to prepare students in information systems for the realities of the business world. Web-based resources have been used to support such pedagogy with mixed results. The paper argues that the design of web-based learning support to cater to different learning styles may give…

  11. The mediating role of demand and control in the relationship between leadership behaviour and employee distress: a cross-sectional study.

    Science.gov (United States)

    Lornudd, Caroline; Tafvelin, Susanne; von Thiele Schwarz, Ulrica; Bergman, David

    2015-02-01

    The relationship between leadership and employee distress is well established, however, the processes involved in this relationship remain largely unclear. For a stretched nursing workforce, understanding in what ways leadership may influence employee distress is particularly important. To examine possible mediating effects of the work environment factors demand and control in the relationship between leadership behaviour in change, production, and employee orientation and employee distress. Cross-sectional study design. The study was conducted at a large county council in Sweden providing both institutional and non-institutional care. A random sample of 1249 employees (primarily nurses, but also a wide range of other healthcare professionals and administrative staff), who had a healthcare manager that was about to enter a leadership development programme (n=171), responded to a web-based questionnaire. The response rate was 62%. The employees rated their healthcare managers' behaviour in change, production, and employee orientation, as well as their own perceptions of level of demand, control (subdivided into decision authority and skill discretion), and five distress outcomes. Multilevel analysis was performed. The mediators demand, decision authority, and skill discretion were significant predictors of all five distress outcomes for all three leadership orientations. In eight of 15 regressions, the mediators fully explained the relationships between leadership orientations and outcomes. Four of five relationships with distress outcomes were fully mediated for change-oriented leadership, whereas two of five outcomes were fully mediated for production- and employee-oriented leadership. In all three leadership orientations, the relationship between the mediator skill discretion and the distress measure disengagement were particularly strong, with B-coefficients (-.44, pmanagers' change-oriented behaviour, and how that aspect is related to employee distress, is

  12. Pricing and inventory control policy for non-instantaneous deteriorating items with time- and price-dependent demand and partial backlogging

    Directory of Open Access Journals (Sweden)

    Hiwa Farughi

    2014-06-01

    Full Text Available Determining the optimal inventory control and selling price for deteriorating items is of great significance. In this paper, a joint pricing and inventory control model for deteriorating items with price- and time-dependent demand rate and time-dependent deteriorating rate with partial backlogging is considered. The objective is to determine the optimal price, the replenishment time, and economic order quantity such that the total profit per unit time is maximized. After modeling the problem, an algorithm is proposed to solve the resulted problem. We also prove that the problem statement is concave function and the optimal solution is indeed global.

  13. 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

  14. 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

    2015-01-01

    . In this presentation in addition to a general discussion of changing demands on the professionals I will in particular focus on how increased international outlook and exchange activities may be one way to promote reflective professional socialization. International educational activities provide both students...... for a general assessment of study content and structure – and at the more essential level it raises questions of the educational socialization processes. If the aim is professionals capable of on-going transformation of their own practices in a complex interplay with new demands and possibilities, then students......’ professional socialization must be an open-ended reflective process and not merely a question of adaptation to established norms and practices. Development of what I will designate professional reflectivity and professional imagination thus become increasingly central educational objectives...

  15. A comparison between the order and the volume fill rates for a base-stock inventory control system under a compound renewal demand process

    DEFF Research Database (Denmark)

    Larsen, Christian; Thorstenson, Anders

    process. We also elaborate on when the order fill rate can be interpreted as the (extended) ready rate. Furthermore, for the case when customer orders are generated by a negative binomial distribution, we show that it is the size of the shape parameter of this distribution that determines the relative......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 exact mathematical expressions for the two fill-rate measures when demand follows a compound renewal...

  16. Synchronous Control Effort Minimized for Magnetic-Bearing-Supported Shaft

    Science.gov (United States)

    Brown, Gerald V.

    2001-01-01

    Various disturbances that are synchronous with the shaft speed can complicate radial magnetic bearing control. These include position sensor target irregularities (runout) and shaft imbalance. The method presented here allows the controller to ignore all synchronous harmonics of the shaft position input (within the closed-loop bandwidth) and to respond only to asynchronous motions. The result is reduced control effort.

  17. Dissemination Protocols to Support Cooperative Adaptive Cruise Control (CACC) Merging

    NARCIS (Netherlands)

    Klein Wolterink, W.; Heijenk, Geert; Karagiannis, Georgios

    2011-01-01

    Cooperative adaptive cruise control (CACC) is a form of cruise control in which vehicles cooperatively control their speed using wireless communication. Previously we have implemented CACC using beaconing: the regular broadcasting of status information using 802.11p. Currently we are concerned with

  18. 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

  19. 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

  20. 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.

  1. 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 equal in values. In [4] it is also demonstrated that although equal ex ante one will ex post observe differences as actual sample paths are different. By including a low-frequency assumption in the model, we are able to derive mathematical expressions of the confidence intervals one will get if OFR...... and VFR are estimated in a simulation using the regenerative method. Through numerical examples we show that of the two service measures it is OFR that can be estimated most accurately. However, simulation results show that the opposite conclusion holds if we instead consider finitehorizon service...

  2. 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

  3. 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.

  4. 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

  5. Demands on response inhibition processes determine modulations of theta band activity in superior frontal areas and correlations with pupillometry - Implications for the norepinephrine system during inhibitory control.

    Science.gov (United States)

    Dippel, Gabriel; Mückschel, Moritz; Ziemssen, Tjalf; Beste, Christian

    2017-08-15

    Response inhibition processes are important for goal-directed behavior and particularly demanded when it is unlikely to inhibit automatically executed responses. It has been suggested that the norepinephrine (NE) system is important to consider for such likelihood effects. As an indirect measure of the NE system activity we used the pupil diameter and integrated this data with neurophysiological (EEG) data and beamforming analyses. The study shows that inhibitory control processes reflected by theta oscillations are strongly modulated by the likelihood to employ these processes and that these mechanisms were related to neural processes in the SMA and SFG. Probably, the modulations observed for theta band activity may reflect modulations in the encoding of a surprise, or conflict signal. Interestingly, correlation analyses of neuronal activity at the sensor and the source level with pupil diameter data revealed strong correlations that were only seen in the condition where inhibitory control processes were rarely demanded. On the basis of findings and theoretical models suggesting that the pupil diameter can be interpreted as a proximate of NE system activity the results may be interpreted that the NE system modulates inhibitory control processes via theta band activity in the SFB when the likelihood to inhibit a prepotent response tendency is low. From this it may be speculated that the NE system dynamically gains and loses relevance to modulate inhibitory control depending on boundary conditions that determine the mode of responding. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. 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

  7. Policy of energy demand control and resistance to change. A socio-anthropological approach; Politique de maitrise de la demande d'energie et resistances au changement. Une approche socio-anthropologique

    Energy Technology Data Exchange (ETDEWEB)

    Zelem, Marie-Christine

    2010-03-15

    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. The Proposal of Demand Estimation of Repairable Items for the Weapon Systems During the Initial Support Period: F-16 Case Study

    Directory of Open Access Journals (Sweden)

    Bahtiyar Eren

    2012-02-01

    Full Text Available Every country that has military systems such as aircraft, radar, warship or tank has to meet the operational needs of those military systems in order to keep them ready for military operations. Logistics support needs are defined basically either before or after procurement. If they are defined before procurement, they are called "initial support requirement", otherwise called "sustainment support requirement". Due to the fact that new system will be added into the Turkish military inventory, it is focused on the initial support requirement phase. In addition to that, it is focused on repairable items since most of the material acquisition cost within the initial support budget is allocated to repairable items. In this study, within the scope of initial support requirements,the method that produces much better results in terms of quantity and cost perspective than the ones used in Turkey and USA is established and demonstrated by using real data set of F-16.

  9. 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

  10. Artificial Intelligence Approach to Support Statistical Quality Control Teaching

    Science.gov (United States)

    Reis, Marcelo Menezes; Paladini, Edson Pacheco; Khator, Suresh; Sommer, Willy Arno

    2006-01-01

    Statistical quality control--SQC (consisting of Statistical Process Control, Process Capability Studies, Acceptance Sampling and Design of Experiments) is a very important tool to obtain, maintain and improve the Quality level of goods and services produced by an organization. Despite its importance, and the fact that it is taught in technical and…

  11. LEGAL SUPPORT FOR PUBLIC CONTROL: PROBLEMS AND PROSPECTS

    Directory of Open Access Journals (Sweden)

    Savchenko M. S.

    2015-06-01

    Full Text Available In the article we reveal the basic problems of forming the legal basis of public control over the activities of public authorities. The relevance of this topic has been steadily increasing due to the increasing influence of civil society on the decisions made by public authorities. The authors analyze the provisions of the Federal Law "On the basis of public control in the Russian Federation", the regional laws, to fix the foundations of social control in some subjects of the federation, as well as other legal acts in this area. Special attention is paid to the formulation of the concept of social control and the conclusion of the need legislative consolidation of the concept of "individual public authority 'and a common list of agencies and organizations that operate them. Analyzing the law enshrined in the range of subjects of public control, the authors substantiate the feasibility of incorporating the Advisory Board at the government and public experts. On the basis of the provisions of the law, in this work we have determined the legal status of the subjects of social control, their powers and procedures of the in collaboration with the authorities, as well as the legal framework for the implementation of certain forms of social control. It is proposed to expand the interaction of subjects of public control with prosecutors by holding regular meetings to expand the powers of public monitoring commissions for visiting places of detention

  12. Evaluation of CUSUM and EWMA Control Charts to Detect Changes in Underlying Demand Trends of Naval Aviation Spares

    Science.gov (United States)

    2010-09-01

    help with information and expert knowledge as this thesis progressed. I thank Ms. Pam Silva and Professor Mary Vizzini for your assistance in...their amazing support and patience while I juggled the requirements of school, work and family. To my Mom, my sisters Ilene and Anna , and my children

  13. Controlled Ecological Life Support System: Regenerative Life Support Systems in Space

    Science.gov (United States)

    Macelroy, Robert D.; Smernoff, David T.

    1987-01-01

    A wide range of topics related to the extended support of humans in space are covered. Overviews of research conducted in Japan, Europe, and the U.S. are presented. The methods and technologies required to recycle materials, especially respiratory gases, within a closed system are examined. Also presented are issues related to plant and algal productivity, efficiency, and processing methods. Computer simulation of closed systems, discussions of radiation effects on systems stability, and modeling of a computer bioregenerative system are also covered.

  14. Charting the effects of TMS with fMRI: Modulation of cortical recruitment within the distributed network supporting semantic control.

    Science.gov (United States)

    Hallam, Glyn P; Whitney, Carin; Hymers, Mark; Gouws, Andre D; Jefferies, Elizabeth

    2016-12-01

    Semantic memory comprises our knowledge of the meanings of words and objects but only some of this knowledge is relevant at any given time. Thus, semantic control processes are needed to focus retrieval on relevant information. Research on the neural basis of semantic control has strongly implicated left inferior frontal gyrus (LIFG) but recent work suggests that a wider network supports semantic control, including left posterior middle temporal gyrus (pMTG), right inferior frontal gyrus (RIFG) and pre-supplementary motor area (pre-SMA). In the current study, we used repetitive transcranial magnetic stimulation (1Hz offline TMS) over LIFG, immediately followed by fMRI, to examine modulation of the semantic network. We compared the effect of stimulation on judgements about strongly-associated words (dog-bone) and weaker associations (dog-beach), since previous studies have found that dominant links can be recovered largely automatically with little engagement of LIFG, while more distant connections require greater control. Even though behavioural performance was maintained in response to TMS, LIFG stimulation increased the effect of semantic control demands in pMTG and pre-SMA, relative to stimulation of a control site (occipital pole). These changes were accompanied by reduced recruitment of both the stimulated region (LIFG) and its right hemisphere homologue (RIFG), particularly for strong associations with low control requirements. Thus repetitive TMS to LIFG modulated the contribution of distributed regions to semantic judgements in two distinct ways.

  15. Increase in water column denitrification during the deglaciation controlled by oxygen demand in the eastern equatorial Pacific

    Directory of Open Access Journals (Sweden)

    P. Martinez

    2009-05-01

    Full Text Available Here we present organic export production and isotopic nitrogen results over the last 30 000 years from one core localized off Costa Rica (ODP Site 1242 on the leading edge of the oxygen minimum zone of the Eastern Tropical North Pacific. Marine export production reveals glacial-interglacial variations with low organic matter (total organic carbon and total nitrogen contents during warm intervals, twice more during cold episodes and double peaked maximum during the deglaciation, between ~15.5–18.5 and 11–13 ka BP. When this new export production record is compared with four nearby cores localized within the Eastern Pacific along the Equatorial divergence, a good agreement between all the cores is observed, with the major feature being a maximum of export during the early deglaciation. As for export production, water-column denitrification represented by sedimentary δ15N records along the Eastern tropical North and South Pacific between 15° N and 36° S is coherent as well over the last deglaciation period. The whole isotopic nitrogen profiles indicate that denitrification increased abruptly at 19 ka BP to a maximum during the early deglaciation, confirming a typical Antarctic timing. It is proposed that the increase in export production and then in subsurface oxygen demand lead to an intensification of water-column denitrification within the oxygen minimum zones in the easternmost Pacific at the time of the last deglaciation. The triggering mechanism would have been primarily linked to an increase in preformed nutrients contents feeding the Equatorial Undercurrent driven by the resumption of overturning in the Southern Ocean and the return of nutrients from the deep ocean to the sea-surface. An increase in equatorial wind-driven upwelling of sub-surface nutrient-rich waters could have played the role of an amplifier.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Self-supported spinel FeCo2O4 nanowire array: an efficient non-noble-metal catalyst for the hydrolysis of NaBH4 toward on-demand hydrogen generation

    Science.gov (United States)

    Hao, Shuai; Yang, Libin; Cui, Liang; Lu, Wenbo; Yang, Yingchun; Sun, Xuping; Asiri, Abdullah M.

    2016-11-01

    NaBH4 has been considered as one of the most advantageous candidates for chemical hydrogen storage, but it is still a huge challenge to design efficient non-noble-metal catalysts for on-demand hydrogen generation from NaBH4 hydrolysis. In this paper, we demonstrate for the first time that a spinel FeCo2O4 nanowire array supported on carbon cloth (FeCo2O4 NA/CC) behaves as an efficient earth-abundant catalyst toward NaBH4 hydrolysis in alkaline solutions with an activation energy of 44.98 kJ mol-1. Such FeCo2O4 NA/CC offers a hydrogen generation rate of 2551 ml min-1 g-1 under ambient conditions, with good stability and reusability. Its use as an ON/OFF switch for on-demand hydrogen generation is also demonstrated successfully.

  1. Three dimensional visualization to support command and control

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Demand Curves for Hypothetical Cocaine in Cocaine-Dependent Individuals

    Science.gov (United States)

    Bruner, Natalie R.; Johnson, Matthew W.

    2013-01-01

    Rationale Drug purchasing tasks have been successfully used to examine demand for hypothetical consumption of abused drugs including heroin, nicotine, and alcohol. In these tasks drug users make hypothetical choices whether to buy drugs, and if so, at what quantity, at various potential prices. These tasks allow for behavioral economic assessment of that drug's intensity of demand (preferred level of consumption at extremely low prices) and demand elasticity (sensitivity of consumption to price), among other metrics. However, a purchasing task for cocaine in cocaine-dependent individuals has not been investigated. Objectives This study examined a novel Cocaine Purchasing Task and the relation between resulting demand metrics and self-reported cocaine use data. Methods Participants completed a questionnaire assessing hypothetical purchases of cocaine units at prices ranging from $0.01 to $1,000. Demand curves were generated from responses on the Cocaine Purchasing Task. Correlations compared metrics from the demand curve to measures of real-world cocaine use. Results Group and individual data were well modeled by a demand curve function. The validity of the Cocaine Purchasing Task was supported by a significant correlation between the demand curve metrics of demand intensity and Omax (determined from Cocaine Purchasing Task data) and self-reported measures of cocaine use. Partial correlations revealed that after controlling for demand intensity, demand elasticity and the related measure, Pmax, were significantly correlated with real-world cocaine use. Conclusions Results indicate that the Cocaine Purchasing Task produces orderly demand curve data, and that these data relate to real-world measures of cocaine use. PMID:24217899

  3. Demand curves for hypothetical cocaine in cocaine-dependent individuals.

    Science.gov (United States)

    Bruner, Natalie R; Johnson, Matthew W

    2014-03-01

    Drug purchasing tasks have been successfully used to examine demand for hypothetical consumption of abused drugs including heroin, nicotine, and alcohol. In these tasks, drug users make hypothetical choices whether to buy drugs, and if so, at what quantity, at various potential prices. These tasks allow for behavioral economic assessment of that drug's intensity of demand (preferred level of consumption at extremely low prices) and demand elasticity (sensitivity of consumption to price), among other metrics. However, a purchasing task for cocaine in cocaine-dependent individuals has not been investigated. This study examined a novel Cocaine Purchasing Task and the relation between resulting demand metrics and self-reported cocaine use data. Participants completed a questionnaire assessing hypothetical purchases of cocaine units at prices ranging from $0.01 to $1,000. Demand curves were generated from responses on the Cocaine Purchasing Task. Correlations compared metrics from the demand curve to measures of real-world cocaine use. Group and individual data were well modeled by a demand curve function. The validity of the Cocaine Purchasing Task was supported by a significant correlation between the demand curve metrics of demand intensity and O max (determined from Cocaine Purchasing Task data) and self-reported measures of cocaine use. Partial correlations revealed that after controlling for demand intensity, demand elasticity and the related measure, P max, were significantly correlated with real-world cocaine use. Results indicate that the Cocaine Purchasing Task produces orderly demand curve data, and that these data relate to real-world measures of cocaine use.

  4. Automated Demand Response and Commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Piette, Mary Ann; Watson, David S.; Motegi, Naoya; Bourassa, Norman

    2005-04-01

    This paper describes the results from the second season of research to develop and evaluate the performance of new Automated Demand Response (Auto-DR) hardware and software technology in large facilities. Demand Response (DR) is a set of activities to reduce or shift electricity use to improve the electric grid reliability and manage electricity costs. Fully-Automated Demand Response does not involve human intervention, but is initiated at a home, building, or facility through receipt of an external communications signal. We refer to this as Auto-DR. The evaluation of the control and communications must be properly configured and pass through a set of test stages: Readiness, Approval, Price Client/Price Server Communication, Internet Gateway/Internet Relay Communication, Control of Equipment, and DR Shed Effectiveness. New commissioning tests are needed for such systems to improve connecting demand responsive building systems to the electric grid demand response systems.

  5. Neural systems supporting the control of affective and cognitive conflicts.

    Science.gov (United States)

    Ochsner, Kevin N; Hughes, Brent; Robertson, Elaine R; Cooper, Jeffrey C; Gabrieli, John D E

    2009-09-01

    Although many studies have examined the neural bases of controlling cognitive responses, the neural systems for controlling conflicts between competing affective responses remain unclear. To address the neural correlates of affective conflict and their relationship to cognitive conflict, the present study collected whole-brain fMRI data during two versions of the Eriksen flanker task. For these tasks, participants indicated either the valence (affective task) or the semantic category (cognitive task) of a central target word while ignoring flanking words that mapped onto either the same (congruent) or a different (incongruent) response as the target. Overall, contrasts of incongruent > congruent trials showed that bilateral dorsal ACC, posterior medial frontal cortex, and dorsolateral pFC were active during both kinds of conflict, whereas rostral medial pFC and left ventrolateral pFC were differentially active during affective or cognitive conflict, respectively. Individual difference analyses showed that separate regions of rostral cingulate/ventromedial pFC and left ventrolateral pFC were positively correlated with the magnitude of response time interference. Taken together, the findings that controlling affective and cognitive conflicts depends upon both common and distinct systems have important implications for understanding the organization of control systems in general and their potential dysfunction in clinical disorders.

  6. 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.

  7. Management Planning and Control: Supporting Knowledge-Intensive Organizations

    Science.gov (United States)

    Herremans, Irene M.; Isaac, Robert G.

    2005-01-01

    Purpose: The purpose of this paper is to develop propositions for empirical validation regarding appropriate management planning and control systems (MPACS) in knowledge-intensive organizations. Design/methodology/approach: The propositions were developed from interviews with members of a knowledge-intensive virtual organization that is known for…

  8. Sociodemographic and Individual Predictors of Performance in an Attentional Task with Alert, Orienting and Control Demands in Preschoolers

    Directory of Open Access Journals (Sweden)

    Colombo, Jorge A.

    2012-08-01

    Full Text Available This study explores the predictive value of socioeconomic status, maternal mental health and child temperament on the performance in the attentional network test (ANT, which assesses attentional processes of alert, orienting and control, administered to 203 4-to-5 years-old children (M = 4.78; SD = .59 from Unsatisfied and Satisfied Basic Needs homes (UBN and SBN, respectively. Results from the linear regression analysis indicated that gender, age, effortful control, and marginally parental occupation, predicted increments in reaction times of trials corresponding only to the control network. Predictors were not verified when sociodemographic variables (parental education and occupation, dwelling and overcrowding were replaced in the model by the predictor socioeconomic group (UBN, SBN. These results suggest a differential modulation of individual and environmental factors on different attentional processing networks.

  9. 基于接纳控制的智能电网需求响应%Demand response based on admission control in smart grid

    Institute of Scientific and Technical Information of China (English)

    马锴; 姚婷; 关新平

    2015-01-01

    Utility functions are used to denote the satisfaction of consumers and formulate demand response as a convex optimization problem. For the case that the power supply can not meet the minimum power consumption of the consumers, two admission control algorithms are designed, combining with distributed power consumption scheduling and real-time pricing. Simulation results show that the admission control makes the consumers meet the minimum power consumption, ensure the power quality of the consumers, and balance the supply and the demand in smart grid.%采用效用函数刻画用户的用电满意度,将需求响应问题建模为一类凸优化问题。针对电力供应商的供电量不能满足用户最小用电需求的问题,结合分布式用电量调度和实时定价,设计两类接纳控制算法。仿真结果表明,通过接纳控制,满足了购电用户的最小用电需求,保证了用户的用电质量,能够实现电网的供需平衡。

  10. 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...

  11. 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.

  12. Integrated Control Strategies Supporting Autonomous Functionalities in Mobile Robots

    OpenAIRE

    Brandon Sights; H.R. Everett; Estrellina Pacis; Greg Kogut; Michael Thompson

    2006-01-01

    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 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 ...

  13. 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.

  14. 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.

  15. The Key Technologies Demanding Prompt Solution in Network Fire Control System%网络火控中一些亟待解决的关键技术

    Institute of Scientific and Technical Information of China (English)

    陈勇; 刘克敏; 孙幸福

    2011-01-01

    According to the actualities that the demestic fire control system development still remains at multi-computer communication system, this paper presents the background and present situation of networks fire control system development. The influence of this trend on weapon system is analyzed briefly. On this basis, we put forward some key technologies demanding prompt solution.%针对国内火控系统发展仍停留在“多计算机通讯体制的现状”,阐述了网络火控的研究背景、现状及发展方向。论述了火控系统信息化、网络化对武器系统的影响,在此基础上提出了网络火控中亟待解决的几个关键问题。

  16. Value sensitive design of automated workload distribution support for traffic control teams

    NARCIS (Netherlands)

    Harbers, M.; Neerincx, M.A.

    2014-01-01

    This paper studies the effects of automated support for workload distribution in traffic control teams on human values such as security, autonomy and privacy. The paper describes a workshop in which the support system's stakeholders, their values, and the effects of the support system on these value

  17. Sleeping position and reported quality of sleep. A comparison between subjects demanding treatment for temporomandibular disorders and controls.

    Science.gov (United States)

    Mundt, Anna-Kerstin Göthe; Helkimo, Martti; Magnusson, Tomas

    2011-01-01

    The aims of the present study were to investigate if there are differences concerning preferred body posture during sleep between 100 patients, 66 women and 34 men, mean age: 49 years (range: 20-85 years) referred to a specialist clinic because of TMD and 100 matched controls from a public dental clinic. The participants were asked to answer a questionnaire with questions about TMD symptoms and neck or shoulder pain. They were also asked about preferred sleeping position as well as about perceived sleep quality. No differences could be found between the two groups in respect of sleeping position. However, significantly more individuals in the TMD group compared to the controls had changed their preferred sleeping position due to their face and/or jaw and/ or neck-shoulder symptoms. Subjects in the TMD group also more frequently stated that they often felt insufficiently rested at awakening and/or felt tired or sleepy in the daytime because of symptoms from face/jaws. A significant number in the control group reported TMD symptoms indicating a latent need for TMD treatment. It is concluded that sleep position seems to have little or no significance for the development or maintenance of TMD symptoms. However, the study indicates that TMD symptoms and associated neck- and shoulder pain affect the quality of sleep.

  18. 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.

  19. 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.

  20. 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

    2017-03-08

    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.

  1. 14 CFR 460.11 - Environmental control and life support systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Environmental control and life support systems. 460.11 Section 460.11 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... Crew § 460.11 Environmental control and life support systems. (a) An operator must provide atmospheric...

  2. How Are Parental Psychological Control and Autonomy-Support Related? A Cluster-Analytic Approach

    Science.gov (United States)

    Soenens, Bart; Vansteenkiste, Maarten; Sierens, Eline

    2009-01-01

    This study addresses the hypothesis that the relationship between parental psychological control and autonomy-support depends on how autonomy-support is conceptualized, that is, in terms of promotion of independence or in terms of promotion of volitional functioning. Questionnaires tapping into psychological control and these two types of…

  3. Interaction between Sex and Social Support in the Control of Type II Diabetes Mellitus.

    Science.gov (United States)

    Heitzmann, Carma A.; Kaplan, Robert M.

    1984-01-01

    Investigated the role of social support in the control of Type II diabetes mellitus. Participants (N=37) in a behavioral program in diabetes care completed questionnaires and provided blood samples. For women, satisfaction with supportive relationships was associated with control of diabetes. The opposite was true for men. (BH)

  4. Why the long hours? Job demands and social exchange dynamics.

    Science.gov (United States)

    Genin, Emilie; Haines, Victor Y; Pelletier, David; Rousseau, Vincent; Marchand, Alain

    2016-11-22

    This study investigates the determinants of long working hours from the perspectives of the demand-control model [Karasek, 1979] and social exchange theory [Blau, 1964; Goulder, 1960]. These two theoretical perspectives are tested to understand why individuals work longer (or shorter) hours. The hypotheses are tested with a representative sample of 1,604 employed Canadians. In line with Karasek's model, the results support that high job demands are positively associated with longer work hours. The social exchange perspective would predict a positive association between skill discretion and work hours. This hypothesis was supported for individuals with a higher education degree. Finally, the results support a positive association between active jobs and longer work hours. Our research suggests that job demands and social exchange dynamics need to be considered together in the explanation of longer (or shorter) work hours.

  5. 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.

  6. Prepotent motor activity and inhibitory control demands in different variants of the go/no-go paradigm.

    Science.gov (United States)

    Wessel, Jan R

    2017-04-08

    Inhibitory control enables humans to stop prepotent motor activity, and is commonly studied using go/no-go or stop-signal tasks. In stop-signal tasks, prepotent motor activity is elicited by delaying stop signals relative to go signals. In go/no-go tasks, however, trials include only one signal-go or no-go. Hence, prepotent motor activity has to be ensured differently-for example, by using rare no-go trials and short trial durations. However, a literature survey shows that ∼40% of studies use equiprobable go/no-go trials and ∼20% use long stimulus-stimulus intervals (> 4 s). It is unclear whether such slow-paced, equiprobable go/no-go tasks elicit prepotent motor activity and probe inhibitory control. We recorded EEG during four go/no-go tasks, varying in no-go probability and trial duration. We quantified prepotent motor activity on successfully inhibited no-go trials using the lateralized readiness potential. Only fast-paced go/no-go tasks with rare no-go trials reliably evoked such activity. We then used a stop-signal task and independent component analysis to isolate an established neural signature of inhibitory control, and investigated this signature's activity across the go/no-go tasks. Across tasks, increased prepotent motor activity on individual no-go trials was accompanied by greater frontocentral P3 amplitudes, confirming it as an index of inhibition. Crucially, this inhibition-related activity showed a 75% reduction in slow-paced, equiprobable go/no-go tasks compared to fast-paced, rare no-go versions. Therefore, since many common go/no-go task configurations do not reliably evoke prepotent motor activity, their inhibitory requirements are greatly reduced. This has major implications for the usage of go/no-go tasks in psychological experiments. © 2017 Society for Psychophysiological Research.

  7. Optimal Control of a Make-to-Stock System with Outsourced Production and Price-Sensitive Demand

    Directory of Open Access Journals (Sweden)

    Liuxin Chen

    2014-01-01

    and a choice of either high or low price, the system decides at any point in time whether to produce or even outsource for additional capacity as well as which price to sell the product at. We show in the paper that the optimal control policy is of dynamic threshold type: all decisions are based on the product inventory position which represents the state of the system; there is a state dependent base stock level to decide on production and a higher level on outsourcing; and there is a state dependent threshold which divides the choice of high and low prices.

  8. Implementation and Control of a Residential Electrothermal Microgrid Based on Renewable Energies, a Hybrid Storage System and Demand Side Management

    Directory of Open Access Journals (Sweden)

    Julio Pascual

    2014-01-01

    Full Text Available This paper proposes an energy management strategy for a residential electrothermal microgrid, based on renewable energy sources. While grid connected, it makes use of a hybrid electrothermal storage system, formed by a battery and a hot water tank along with an electrical water heater as a controllable load, which make possible the energy management within the microgrid. The microgrid emulates the operation of a single family home with domestic hot water (DHW consumption, a heating, ventilation and air conditioning (HVAC system as well as the typical electric loads. An energy management strategy has been designed which optimizes the power exchanged with the grid profile in terms of peaks and fluctuations, in applications with high penetration levels of renewables. The proposed energy management strategy has been evaluated and validated experimentally in a full scale residential microgrid built in our Renewable Energy Laboratory, by means of continuous operation under real conditions. The results show that the combination of electric and thermal storage systems with controllable loads is a promising technology that could maximize the penetration level of renewable energies in the electric system.

  9. Diabetes self-care behaviors and disease control in support group attenders and nonattenders.

    Science.gov (United States)

    Chiou, Chii-Jun

    2014-12-01

    The prevalence rate and mortality rate of diabetes continue to increase annually. Complications associated with poor control of diabetes include renal dialysis, amputation, heart disease, stroke, retinopathy, and vascular disease, all of which have an impact at the individual, family, and national level. This study compares diabetes self-care behavior and disease control efficacy between attenders and nonattenders of a diabetes support group. We used a questionnaire with good validity and reliability to conduct a cross-sectional survey. Diabetes support groups have been established throughout Taiwan for around 2 years. Participants for this study were recruited randomly from a register of support group participants. Support group instructors were asked to collect questionnaires from those attending and not attending their support groups. Ten groups volunteered to participate in this study. We received 147 valid questionnaires from participants attending support groups (attenders) and 93 questionnaires from participants who did not (nonattenders). There were no statistically significant differences between support group attenders and nonattenders in terms of age, educational level, or time since diagnosis of diabetes. Thus, we assumed these two groups as adequately similar to conduct statistical comparisons. Scores for diabetes self-care behavior, disease control, and use of the diabetes passport were all significantly higher among support group attenders than their nonattender peers. Results indicate that people attending diabetes support groups are more likely to have better self-care behavior and disease control than nonattenders. Therefore, we suggest that the government actively promote policies supportive of diabetes support groups.

  10. A comparison of the stress-strain process for business owners and nonowners: differences in job demands, emotional exhaustion, satisfaction, and social support.

    Science.gov (United States)

    Tetrick, L E; Slack, K J; Da Silva, N; Sinclair, R R

    2000-10-01

    One hundred sixty licensed morticians were surveyed to examine differences among business owners, managers, and employees on the relations proposed by G. F. Koeske and R. D. Koeske's (1993) stressor-strain-outcome model. Forty-eight percent of the morticians were owners, 16% were managers, and 36% were employees. Owners had less social support from work-related sources and perceived lower levels of role ambiguity and role conflict, less emotional exhaustion, and higher levels of job satisfaction and professional satisfaction than did nonowners. Social support from work-related sources and ownership each moderated the relationship between emotional exhaustion and job satisfaction but not between emotional exhaustion and professional satisfaction. Emotional exhaustion partially mediated the effect of stressors on job satisfaction and professional satisfaction.

  11. Temperature and Humidity Control in Air-Conditioned Buildings with lower Energy Demand and increased Indoor Air Quality

    DEFF Research Database (Denmark)

    Paul, Joachim; Martos, E. T.

    2003-01-01

    %. For indoor air temperature and humidity control, the use of an ice slurry (´Binary Ice´)was compared to conventional chilled water. The use of Binary Ice instead of chilled water makes the air handling and air distribution installation much simpler, recirculation of air becomes obsolete, and a higher portion....... Binary Ice as secondary refrigerant for air-conditioning purposes is an economical and technically feasible solution in any climate. Whatever chilled water can do in an air-conditioning installation ? Binary Ice can do it better....... of ambient air can be supplied, thus improving the indoor air quality still further. Reheating of air is not necessary when using Binary Ice. The introduction of chilled air into a room requires a different type of air outlet, however. When using Binary Ice, energy savings are high for climates with low...

  12. Laboratory support of drug abuse control programs: an overview.

    Science.gov (United States)

    Decker, W J

    1977-01-01

    Labeling an individual a drug abuser has serious sociologic and legal implications that only laboratory testing can effectively allay. A proper specimen (both qualitatively and quantitatively) must be obtained for analysis. Positive identification of specimen with subject is of paramount importance. The problems of specimen substitution--other people's urine, tap water, apple juice--directly impinge here, as does the possibility of drug degradation by heat, light, and microbial attack and of drug adsorption by the container and urinary sediment. Confirmation of postives indicated by screening tests (thin layer chromatography and immunoassays) by gas chromatography and/or ultraviolet spectrophotometry is, in most situations, mandatory. An effective quality control program is an absolute requirement. Even under ideal circumstances, laboratory results can sometimes wrongly indicate the abuse of drugs; and conversely, drug abuse can take place without detection by the laboratory. As in any clinical situation, laboratory tests are only a part (albeit an important one) of the entire evaluation of the individual involved.

  13. A New TCP Congestion Control Supporting RTT-Fairness

    Science.gov (United States)

    Ogura, Kazumine; Nemoto, Yohei; Su, Zhou; Katto, Jiro

    This paper focuses on RTT-fairness of multiple TCP flows over the Internet, and proposes a new TCP congestion control named “HRF (Hybrid RTT-Fair)-TCP”. Today, it is a serious problem that the flows having smaller RTT utilize more bandwidth than others when multiple flows having different RTT values compete in the same network. This means that a user with longer RTT may not be able to obtain sufficient bandwidth by the current methods. This RTT fairness issue has been discussed in many TCP papers. An example is CR (Constant Rate) algorithm, which achieves RTT-fairness by multiplying the square of RTT value in its window increment phase against TCP-Reno. However, the method halves its windows size same as TCP-Reno when a packet loss is detected. This makes worse its efficiency in certain network cases. On the other hand, recent proposed TCP versions essentially require throughput efficiency and TCP-friendliness with TCP-Reno. Therefore, we try to keep these advantages in our TCP design in addition to RTT-fairness. In this paper, we make intuitive analytical models in which we separate resource utilization processes into two cases: utilization of bottleneck link capacity and that of buffer space at the bottleneck link router. These models take into account three characteristic algorithms (Reno, Constant Rate, Constant Increase) in window increment phase where a sender receives an acknowledgement successfully. Their validity is proved by both simulations and implementations. From these analyses, we propose HRF-TCP which switches two modes according to observed RTT values and achieves RTT fairness. Experiments are carried out to validate the proposed method. Finally, HRF-TCP outperforms conventional methods in RTT-fairness, efficiency and friendliness with TCP-Reno.

  14. A feedback-controlled treadmill (treadmill-on-demand) and the spontaneous speed of walking and running in humans.

    Science.gov (United States)

    Minetti, Alberto E; Boldrini, Lorenzo; Brusamolin, Laura; Zamparo, Paola; McKee, Tom

    2003-08-01

    A novel apparatus, composed by a controllable treadmill, a computer, and an ultrasonic range finder, is here proposed to help investigation of many aspects of spontaneous locomotion. The acceleration or deceleration of the subject, detected by the sensor and processed by the computer, is used to accelerate or decelerate the treadmill in real time. The system has been used to assess, in eight subjects, the self-selected speed of walking and running, the maximum "reasonable" speed of walking, and the minimum reasonable speed of running at different gradients (from level up to +25%). This evidenced the speed range at which humans neither walk nor run, from 7.2 +/- 0.6 to 8.4 +/- 1.1 km/h for level locomotion, slightly narrowing at steeper slopes. These data confirm previous results, obtained indirectly from stride frequency recordings. The self-selected speed of walking decreases with increasing gradient (from 5.0 +/- 0.8 km/h at 0% to 3.0 +/- 0.9 km/h at +25%) and seems to be approximately 30% higher than the speed that minimizes the metabolic energy cost of walking, obtained from the literature, at all the investigated gradients. The advantages, limitations, and potential applications of the newly proposed methodology in physiology, biomechanics, and pathology of locomotion are discussed in this paper.

  15. Impact of the demand for 'proxy assent' on recruitment to a randomised controlled trial of vaccination testing in care homes.

    Science.gov (United States)

    Whelan, Paul James; Walwyn, Rebecca; Gaughran, Fiona; Macdonald, Alastair

    2013-01-01

    Legal frameworks are in place to protect those who lack the capacity to consent to research, such as the Mental Capacity Act in the UK. Assent is sought instead from a proxy, usually a relative. However, the same legislation may, perversely, affect the welfare of those who lack capacity and of others by hindering the process of recruitment into otherwise potentially beneficial research. In addition, the onus of responsibility is moved from those who know most about the study (ie, the scientific community) to those who know less (the proxies). In this paper, we describe the characteristics of a sample at different stages of the recruitment process of an influenza vaccine-based randomised control trial in elderly care home residents (the FEVER study). 62% (602/968) of potential subjects lacked capacity but only 29% (80/277) of those actually randomised. Older age, being female and living in an Elderly Mentally Ill care home were the only variables associated with lacking capacity. Considering this was a study based in a care home setting where the prevalence of dementia approximates 80%, the trial, like many others, was thus significantly biased. We believe that difficulties seeking proxy assent contributed significantly to this problem. Further thought should be given to how assent to enter research for those who lack capacity should be provided, and we suggest avenues for further discussion such as independent risk/benefit expert panels.

  16. ORION Environmental Control and Life Support Systems Suit Loop and Pressure Control Analysis

    Science.gov (United States)

    Eckhardt, Brad; Conger, Bruce; Stambaugh, Imelda C.

    2015-01-01

    Under NASA's ORION Multi-Purpose Crew Vehicle (MPCV) Environmental Control and Life Support System (ECLSS) Project at Johnson Space Center's (JSC), the Crew and Thermal Systems Division has developed performance models of the air system using Thermal Desktop/FloCAD. The Thermal Desktop model includes an Air Revitalization System (ARS Loop), a Suit Loop, a Cabin Loop, and Pressure Control System (PCS) for supplying make-up gas (N2 and O2) to the Cabin and Suit Loop. The ARS and PCS are designed to maintain air quality at acceptable O2, CO2 and humidity levels as well as internal pressures in the vehicle Cabin and during suited operations. This effort required development of a suite of Thermal Desktop Orion ECLSS models to address the need for various simulation capabilities regarding ECLSS performance. An initial highly detailed model of the ARS Loop was developed in order to simulate rapid pressure transients (water hammer effects) within the ARS Loop caused by events such as cycling of the Pressurized Swing Adsorption (PSA) Beds and required high temporal resolution (small time steps) in the model during simulation. A second ECLSS model was developed to simulate events which occur over longer periods of time (over 30 minutes) where O2, CO2 and humidity levels, as well as internal pressures needed to be monitored in the cabin and for suited operations. Stand-alone models of the PCS and the Negative Pressure relief Valve (NPRV) were developed to study thermal effects within the PCS during emergency scenarios (Cabin Leak) and cabin pressurization during vehicle re-entry into Earth's atmosphere. Results from the Orion ECLSS models were used during Orion Delta-PDR (July, 2014) to address Key Design Requirements (KDR's) for Suit Loop operations for multiple mission scenarios.

  17. Subjetividad Adolescente: Tendiendo Puentes Entre la Oferta y Demanda de Apoyo Psicosocial Para Jóvenes Adolescent Subjectivity: Tending Bridges Between Offer and Demand of Psycho-Social Support for Youth

    Directory of Open Access Journals (Sweden)

    Christian Berger

    2004-11-01

    Full Text Available El presente artículo reflexiona en torno a la tensión existente entre la oferta de programas y servicios para adolescentes y la demanda de apoyo y servicios de este grupo poblacional. Se plantea que dada la ausencia de la perspectiva adolescente en el desarrollo de programas y políticas dirigidas a dicha población, la oferta programática responde a creencias y expectativas del mundo adulto. Se propone que la subjetividad adolescente debe ser reconocida e integrada con el objeto de articular en mejor forma la oferta y demanda de programas y servicios para jóvenes. A través del análisis de las nociones de apoyo psicosocial (como oferta y las conductas de búsqueda de apoyo (desde la perspectiva de la demanda, el presente artículo pretende iluminar la discusión respecto de cómo enfocar el diseño e implementación de programas y políticas que estén orientadas a promover el desarrollo juvenil.The present article reflects on the existing tension between the programmatic offer for youth and the demand for support and services by this population. It is argued that the absence of the adolescent perspective in the development of programs and policies oriented to this population, the offer of programs and services responds to beliefs and expectancies displayed by the adult world. It is proposed that adolescent subjectivity should be acknowledged and integrated in order to achieve a better matching between offer and demand of youth programs and services. Through the analysis of the notions of psycho-social support (as offer and the adolescent help-seeking behavior (from the demand's perspective, the present article intends to enlighten the discussion about how to approach the design and implementation of programs and policies aimed to foster adolescent development.

  18. Study on supporting force sensing and control during large aperture space mirror test

    Science.gov (United States)

    Zhang, Long; Hu, Wenqi; Zheng, Liehua; Hao, Peiming

    2016-10-01

    During the machining of large aperture lightweight space mirror, the mirror figure consistency between ground test and space mission is a problem. In order to effectively control the supporting deformation effect on test results in gravity environment, in view of a 1.2-m space mirror with back blind holes, a supporting method for optical axis horizontal test is proposed, with this method, mirror under test is positioned by three center hole surfaces and supported by six external hole surfaces. The effect of deformation caused by different supporting force value, area and position is analyzed by finite element method, the simulation results show that this supporting method can control the mirror supporting deformation within PV0.035λ rms0.005λ. The actual supporting system uses soft expansion mandrel to control the mirror position and pneumatic lever to realize the floating support. In order to ensure that the support force can evenly distribute on the contact surface, a pressure mapping system is adopted to measure the interface pressure between the mirror blind holes and the soft supporting pads for the first time. This method can meet the test requirements of rms=1/40λ mirror and provides a technical support for high precision test of large aperture space mirror with back blind holes.

  19. Demand and support input: the starting point of political system analysis theory%需求和支持的输入:政治系统分析理论的起点

    Institute of Scientific and Technical Information of China (English)

    孙强强

    2015-01-01

    本文详细探讨了伊斯顿在《政治生活的系统分析》一书中关于政治系统分析的理论中的需求和支持的输入,并认为需求和支持的输入是政治系统分析理论的起点.只有具备了社会欲望和利益的需求源源不断的进入到政治系统之内和政治系统内外成员对其产生很强烈的支持,才会使得各种社会需求顺利的进入到政治系统之内.%This paper discusses the Easton in the political life of the system analysis, in a book about the theory of the analysis of the political system and the input, and that support demand and the input is the starting point of the theory of analysis of political system. Only with the desire and interest of the society needs a steady stream of into within the political system and political system and members of the generated strong support, will make all kinds of social demand smoothly into the political system.

  20. 电力市场化改革背景下电力需求响应机制与支撑技术%Electric Power Demand Response Mechanism and Support Technology Under Electric Power Market Reform

    Institute of Scientific and Technical Information of China (English)

    庞鹏

    2016-01-01

    This paper summarizes theories and practices about demand response in domestic and overseas and concludes types, mechanism,evaluation systems and key support technologies of electric power demand response.In allusion to the situation of electric power response entering into business implementation stage under background of present electric power market re-form,it proposes theoretical architectures of electric power response including overall object for business implementation, response mechanism,performance evaluation method and support technology.%全面梳理国内外实施需求响应的理论与实践,系统归纳电力需求响应的类型、机制、评价体系和支撑关键技术。针对当前电力市场化改革背景下电力需求响应正进入商业化实施阶段,提出电力需求响应理论架构,包括需求响应商业化实施总体目标、响应机制、性能评价方法与支撑技术等关键要素。

  1. On-Demand Special Use Airspace Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We design and develope a Decision Support Tool (DST) that supports On-Demand Special Use Airspace (SUA) scheduling and flight plan optimization around SUA between...

  2. On-Demand Special Use Airspace Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We design and develop a Decision Support Tool (DST) that supports On-Demand Special Use Airspace (SUA) scheduling and flight plan optimization around SUA between...

  3. Perception of family support is correlated with glycemic control in Greeks with diabetes mellitus.

    Science.gov (United States)

    Ilias, I; Hatzimichelakis, E; Souvatzoglou, A; Anagnostopoulou, T; Tselebis, A

    2001-06-01

    We studied 98 native Greek patients with Type 2 diabetes mellitus. Their degree of glycemic control, evaluated with glycated hemoglobin A1c levels, was correlated with perceived family support, assessed with the Family Support Scale. The different social context of Greece--and its corresponding perception of family support--influence glycemic control in a way that is at variance from data of some studies of Anglo-Saxon families. In conclusion, family support should be taken into consideration in the management of native Greek patients with Type 2 diabetes mellitus.

  4. Self-esteem, social support perception and seizure controllability perception in adolescents with epilepsy

    Directory of Open Access Journals (Sweden)

    Nathália F. Siqueira

    2011-10-01

    Full Text Available OBJECTIVE: Compare the self-esteem of adolescents with epilepsy and adolescents without epilepsy and relate it to social support and seizure controllability perception. METHOD: The study sample consisted: case participants (34 subjects attending the pediatric epilepsy clinic of University Hospital and control participants (30 subjects from public schools in Campinas-SP. The instruments utilized were: identification card with demographic and epilepsy data, a semi-structured interview on aspects of the disease, and a Self-Esteem Multidimensional Scale. RESULTS: There was no significant difference between the two groups but majority of adolescents with epilepsy presented higher self esteem rate, have knowledge about epilepsy, presented high levels of social support and seizure controllability perception. There was no significant relationship between social support and seizure controllability perception with self-esteem. CONCLUSION: Knowledge about epilepsy, social support such good controllability seizure perception seem are important contingencies for a better evaluation of self esteem in adolescents with epilepsy.

  5. Improving Pediatric Basic Life Support Performance Through Blended Learning With Web-Based Virtual Patients: Randomized Controlled Trial.

    Science.gov (United States)

    Lehmann, Ronny; Thiessen, Christiane; Frick, Barbara; Bosse, Hans Martin; Nikendei, Christoph; Hoffmann, Georg Friedrich; Tönshoff, Burkhard; Huwendiek, Sören

    2015-07-02

    E-learning and blended learning approaches gain more and more popularity in emergency medicine curricula. So far, little data is available on the impact of such approaches on procedural learning and skill acquisition and their comparison with traditional approaches. This study investigated the impact of a blended learning approach, including Web-based virtual patients (VPs) and standard pediatric basic life support (PBLS) training, on procedural knowledge, objective performance, and self-assessment. A total of 57 medical students were randomly assigned to an intervention group (n=30) and a control group (n=27). Both groups received paper handouts in preparation of simulation-based PBLS training. The intervention group additionally completed two Web-based VPs with embedded video clips. Measurements were taken at randomization (t0), after the preparation period (t1), and after hands-on training (t2). Clinical decision-making skills and procedural knowledge were assessed at t0 and t1. PBLS performance was scored regarding adherence to the correct algorithm, conformance to temporal demands, and the quality of procedural steps at t1 and t2. Participants' self-assessments were recorded in all three measurements. Procedural knowledge of the intervention group was significantly superior to that of the control group at t1. At t2, the intervention group showed significantly better adherence to the algorithm and temporal demands, and better procedural quality of PBLS in objective measures than did the control group. These aspects differed between the groups even at t1 (after VPs, prior to practical training). Self-assessments differed significantly only at t1 in favor of the intervention group. Training with VPs combined with hands-on training improves PBLS performance as judged by objective measures.

  6. Contribution of family social support to the metabolic control of people with diabetes mellitus: A randomized controlled clinical trial.

    Science.gov (United States)

    Gomes, Lilian Cristiane; Coelho, Anna Claudia Martins; Gomides, Danielle Dos Santos; Foss-Freitas, Maria Cristina; Foss, Milton César; Pace, Ana Emilia

    2017-08-01

    This randomized controlled clinical trial aimed to evaluate the contribution of family social support to the clinical/metabolic control of people with type 2 diabetes mellitus. Diabetes mellitus is a chronic disease that requires continuous care in order for individuals to reach glycemic control, the primordial goal of treatment. Family social support is essential to the development of care skills and their maintenance. However, there are few studies that investigate the contribution of family social support to diabetes control. The study was developed between June 2011 and May 2013, and included 164 people who were randomized using simple randomization. The intervention group differed from the control group in that it included a family caregiver, who was recognized by the patient as a source of social support. The educational interventions received by people with diabetes mellitus were used as the basis of the education provided through telephone calls to patients' family members and caregivers, and their purpose was to encourage dialogue between the patients and their relatives about the topics related to diabetes. Regarding the clinical impact, the results showed that there was a greater reduction in blood pressure and glycated hemoglobin in the intervention group than in the control group, showing a positive effect on the control of the disease. Families should be incorporated into the care of people with diabetes mellitus and especially in health care programs, in particular those that can promote different forms of social support to strengthen the bond between family members. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Demand Forecasting Errors

    OpenAIRE

    Mackie, Peter; Nellthorp, John; Laird, James

    2005-01-01

    Demand forecasts form a key input to the economic appraisal. As such any errors present within the demand forecasts will undermine the reliability of the economic appraisal. The minimization of demand forecasting errors is therefore important in the delivery of a robust appraisal. This issue is addressed in this note by introducing the key issues, and error types present within demand fore...

  8. Do Job Demands of Chinese Manufacturing Employees Predict Positive or Negative Outcomes? A Test of Competing Hypotheses.

    Science.gov (United States)

    Cheung, Janelle H; Sinclair, Robert R; Shi, Junqi; Wang, Mo

    2015-12-01

    Karasek's job demands-control (JDC) model posits that job control can buffer against the harmful effects of demands experienced by employees. A large volume of JDC research has obtained support for the main effects of demands and control, but not the interactive effects. Recent research on the challenge-hindrance stressors framework, however, found that work stressors may not always be deleterious, suggesting alternative hypotheses about the effects of demands and control. The present study therefore examined competing hypotheses concerning the effects of job demands on occupational health outcomes. Using a sample of 316 employees in a Chinese manufacturing company, we found that, consistent with the challenge-hindrance framework, production demands were challenge stressors associated with favourable outcomes (i.e. job satisfaction and psychological well-being). In addition, results showed that the interactive role of job control depended on the nature of outcome variables. Future recommendations and implications of findings are discussed.

  9. Effect of Postural Control Demands on Early Visual Evoked Potentials during a Subjective Visual Vertical Perception Task in Adolescents with Idiopathic Scoliosis

    Directory of Open Access Journals (Sweden)

    Yi-Tzu Chang

    2017-06-01

    Full Text Available Subjective visual vertical (SVV judgment and standing stability were separately investigated among patients with adolescent idiopathic scoliosis (AIS. Although, one study has investigated the central mechanism of stability control in the AIS population, the relationships between SVV, decreased standing stability, and AIS have never been investigated. Through event-related potentials (ERPs, the present study examined the effect of postural control demands (PDs on AIS central mechanisms related to SVV judgment and standing stability to elucidate the time-serial stability control process. Thirteen AIS subjects (AIS group and 13 age-matched adolescents (control group aged 12–18 years were recruited. Each subject had to complete an SVV task (i.e., the modified rod-and-frame [mRAF] test as a stimulus, with online electroencephalogram recording being performed in the following three standing postures: feet shoulder-width apart standing, feet together standing, and tandem standing. The behavioral performance in terms of postural stability (center of pressure excursion, SVV (accuracy and reaction time, and mRAF-locked ERPs (mean amplitude and peak latency of the P1, N1, and P2 components was then compared between the AIS and control groups. In the behavioral domain, the results revealed that only the AIS group demonstrated a significantly accelerated SVV reaction time as the PDs increased. In the cerebral domain, significantly larger P2 mean amplitudes were observed during both feet shoulder-width-apart standing and feet together standing postures compared with during tandem standing. No group differences were noted in the cerebral domain. The results indicated that (1 during the dual-task paradigm, a differential behavioral strategy of accelerated SVV reaction time was observed in the AIS group only when the PDs increased and (2 the decrease in P2 mean amplitudes with the increase in the PD levels might be direct evidence of the competition for

  10. Effect of Postural Control Demands on Early Visual Evoked Potentials during a Subjective Visual Vertical Perception Task in Adolescents with Idiopathic Scoliosis.

    Science.gov (United States)

    Chang, Yi-Tzu; Meng, Ling-Fu; Chang, Chun-Ju; Lai, Po-Liang; Lung, Chi-Wen; Chern, Jen-Suh

    2017-01-01

    Subjective visual vertical (SVV) judgment and standing stability were separately investigated among patients with adolescent idiopathic scoliosis (AIS). Although, one study has investigated the central mechanism of stability control in the AIS population, the relationships between SVV, decreased standing stability, and AIS have never been investigated. Through event-related potentials (ERPs), the present study examined the effect of postural control demands (PDs) on AIS central mechanisms related to SVV judgment and standing stability to elucidate the time-serial stability control process. Thirteen AIS subjects (AIS group) and 13 age-matched adolescents (control group) aged 12-18 years were recruited. Each subject had to complete an SVV task (i.e., the modified rod-and-frame [mRAF] test) as a stimulus, with online electroencephalogram recording being performed in the following three standing postures: feet shoulder-width apart standing, feet together standing, and tandem standing. The behavioral performance in terms of postural stability (center of pressure excursion), SVV (accuracy and reaction time), and mRAF-locked ERPs (mean amplitude and peak latency of the P1, N1, and P2 components) was then compared between the AIS and control groups. In the behavioral domain, the results revealed that only the AIS group demonstrated a significantly accelerated SVV reaction time as the PDs increased. In the cerebral domain, significantly larger P2 mean amplitudes were observed during both feet shoulder-width-apart standing and feet together standing postures compared with during tandem standing. No group differences were noted in the cerebral domain. The results indicated that (1) during the dual-task paradigm, a differential behavioral strategy of accelerated SVV reaction time was observed in the AIS group only when the PDs increased and (2) the decrease in P2 mean amplitudes with the increase in the PD levels might be direct evidence of the competition for central

  11. Semi-active control of a cable-stayed bridge under multiple-support excitations

    Institute of Scientific and Technical Information of China (English)

    代泽兵; 黄金枝; 王红霞

    2004-01-01

    This paper presents a semi-active strategy for seismic protection of a benchmark cable-stayed bridge with consideration of multiple-support excitations. In this control strategy, Magnetorheological (MR) dampers are proposed as control devices, a LQG-clipped-optimal control algorithm is employed. An active control strategy, shown in previous researches to perform well at controlling the benchmark bridge when uniform earthquake motion was assumed, is also used in this study to control this benchmark bridge with consideration of multiple-support excitations. The performance of active control system is compared to that of the presented semi-active control strategy. Because the MR fluid damper is a controllable energy- dissipation device that cannot add mechanical energy to the structural system, the proposed control strategy is fail-safe in that bounded-input, bounded-output stability of the controlled structure is guaranteed. The numerical results demonstrated that the performance of the presented control design is nearly the same as that of the active control system; and that the MR dampers can effectively be used to control seismically excited cable-stayed bridges with multiple-support excitations.

  12. Developing a Toolset Supporting the Construction of Reusable Components for Embedded Control Systems

    DEFF Research Database (Denmark)

    Guan, Wei; Sierszecki, Krzysztof; Angelov, Christo K.

    2010-01-01

    Reusing software components for embedded control applications enhances product quality and reduces time to market when appropriate (formal) methodologies and supporting toolsets are available. That is why industrial companies are interested in developing trusted, in-house reusable components for ...

  13. A three-degree-of-freedom hybrid vibration isolation system using adaptive proportional control supported by passive weight support mechanism

    Science.gov (United States)

    Liu, Yun-Hui; Wu, Wei-Hao; Chu, Chih-Liang

    2013-10-01

    This paper presents a three-degree-of-freedom hybrid vibration isolation system integrated with an active sky-hook damper and a passive weight support mechanism for highly sensitive measurement equipment, e.g. atomic force microscopes, suffering from building vibration. Active sky-hook damper applies proportional controller incorporated with an adaptive filter to reduce the resonance of the passive weight support mechanism at nature frequency. The absolute vibration velocity signal acquired from an accelerator and being processed through an integrator is input to the controller as a feedback signal, and the controller output signal drives the voice coil actuator to produce a sky-hook damper force. The adaptive filter is used to compensate the phase error between the measuring input signal and the absolute vibration velocity. An analysis of this active vibration isolation system is presented, and model predictions are compared to experimental results. The results show that the system could effectively reduce transmissibility at resonance without the penalty of increased transmissibility at higher frequencies both in vertical and horizontal directions.

  14. Cloud Computing for the Grid: GridControl: A Software Platform to Support the Smart Grid

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-02-08

    GENI Project: Cornell University is creating a new software platform for grid operators called GridControl that will utilize cloud computing to more efficiently control the grid. In a cloud computing system, there are minimal hardware and software demands on users. The user can tap into a network of computers that is housed elsewhere (the cloud) and the network runs computer applications for the user. The user only needs interface software to access all of the cloud’s data resources, which can be as simple as a web browser. Cloud computing can reduce costs, facilitate innovation through sharing, empower users, and improve the overall reliability of a dispersed system. Cornell’s GridControl will focus on 4 elements: delivering the state of the grid to users quickly and reliably; building networked, scalable grid-control software; tailoring services to emerging smart grid uses; and simulating smart grid behavior under various conditions.

  15. Control interfaces to actively support the arm function of men with Duchenne Muscular Dystrophy

    NARCIS (Netherlands)

    Lobo Prat, Joan

    2016-01-01

    Adults with DMD can benefit from active arm supports that augment their residual functional capabilities. However, intuitively controlled and fully actuated arm supports are currently not commercially available and adults with DMD are limited to use external robotic arms which contribute to the disu

  16. Social Support, Perceived Control, and Well-Being: A Study of an Environmentally Stressed Population.

    Science.gov (United States)

    Levitt, Mary J.; And Others

    1987-01-01

    Interviewed 92 elderly residents of area targeted for massive redevelopment. Findings revealed that each health, control, and support emerged as independent predictors of affect and life satisfaction, and that affect was significantly lower for those with no close support figure than for those with one close relationship. (Author/NB)

  17. Management control of support services : Organizational embeddedness and non-strategic IT

    NARCIS (Netherlands)

    Lau, La E.; Laan, van der M.; Kruis, A.; Speklé, R.F.

    2012-01-01

    This chapter provides evidence on the factors that influence the design of the control arrangements that govern support services. Specifically, we study sourcing decisions of non-strategic information technology (IT) support services. While the popular management literature suggests to outsource non

  18. Construction of intelligent decision support system in control of gas compression process

    Directory of Open Access Journals (Sweden)

    Леонид Михайлович Замиховский

    2015-04-01

    Full Text Available The necessity to construct the intelligent decision support systems (IDSS in the control of the gas compression process with inclusion in structure of the training module is substantiated. А block diagram of human-computer interaction in the system "Dispatcher - IDSS - ASC GCU - CS" is shown, and the functions of the separate blocks of the intellectual decision support system in the control of the gas compression process are defined

  19. Evaluation guideline for the study of the radiological impact of based nuclear installations (INB) presented in support of releases authorization demands; Guide d'examen pour l'etude de l'impact radiologique d'une installation nucleaire de base (INB) fournie a l'appui des demandes d'autorisation de rejets

    Energy Technology Data Exchange (ETDEWEB)

    Chartier, M.; Despres, A.; Supervil, S.; Conte, D.; Hubert, P.; Oudiz, A.; Champion, D

    2002-10-01

    In the case of a license demand for the effluents release and water taking for a nuclear installation, the operating must realize a study of the nuclear effluents radiological impact on the environment and the public health. In this context, the study presents technical and methodological specifications which led the Direction of the Nuclear Installations Safety (DSIN) and the General Direction of the Health (DGS) to ask the IPSN the elaboration of a guideline to help these studies evaluation. The guideline presents the regulatory context, the description of the installations, the treatment and the control processes, the rules of management, the description of the environment, the estimation of the radiological impacts and the environment control system definition. (A.L.B.)

  20. Rewarding yet demanding

    DEFF Research Database (Denmark)

    Bjørkedal, S T B; Torsting, A M B; Møller, T

    2016-01-01

    AIM: The purpose of this study, by exploring client perspectives, was to achieve a better understanding of how people with schizophrenia experience an occupational therapy intervention designed to enable them to carry out meaningful occupations in the early phases of recovery. METHOD: A qualitative......, as demanding. Participants valued engaging in real-life occupations while anchoring new strategies but also the occupational therapist's role in dealing with failure. Participants felt the intervention assisted in their recovery process and enabled them to engage in meaningful occupations. CONCLUSION......: The study provided unique insight into how participants experienced a client-centred partnership with an occupational therapist in the early phases of recovery. The intervention was feasible and supported the participants' recovery process....